"Robert P. J. Day" | 63fc1a9 | 2006-07-02 19:47:05 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 2 | /* |
Denys Vlasenko | 385b456 | 2010-03-26 10:09:34 +0100 | [diff] [blame] | 3 | * udhcp client |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 4 | * Russ Dill <Russ.Dill@asu.edu> July 2001 |
| 5 | * |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 19 | */ |
Denys Vlasenko | f7683cd | 2016-11-23 18:54:59 +0100 | [diff] [blame] | 20 | //applet:IF_UDHCPC(APPLET(udhcpc, BB_DIR_SBIN, BB_SUID_DROP)) |
| 21 | |
| 22 | //kbuild:lib-$(CONFIG_UDHCPC) += common.o packet.o signalpipe.o socket.o |
| 23 | //kbuild:lib-$(CONFIG_UDHCPC) += dhcpc.o |
| 24 | //kbuild:lib-$(CONFIG_FEATURE_UDHCPC_ARPING) += arpping.o |
| 25 | //kbuild:lib-$(CONFIG_FEATURE_UDHCP_RFC3397) += domain_codec.o |
| 26 | |
Denis Vlasenko | af1c843 | 2007-03-26 13:22:35 +0000 | [diff] [blame] | 27 | #include <syslog.h> |
Denis Vlasenko | 1caca34 | 2007-08-02 10:14:29 +0000 | [diff] [blame] | 28 | /* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */ |
| 29 | #define WANT_PIDFILE 1 |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 30 | #include "common.h" |
| 31 | #include "dhcpd.h" |
| 32 | #include "dhcpc.h" |
Denis Vlasenko | 5a3395b | 2006-11-18 19:51:32 +0000 | [diff] [blame] | 33 | |
Dan Fandrich | f533ec8 | 2011-06-10 05:17:59 +0200 | [diff] [blame] | 34 | #include <netinet/if_ether.h> |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 35 | #include <linux/filter.h> |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 36 | #include <linux/if_packet.h> |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 37 | |
Denys Vlasenko | f2bf20f | 2015-10-08 18:13:57 +0200 | [diff] [blame] | 38 | #ifndef PACKET_AUXDATA |
| 39 | # define PACKET_AUXDATA 8 |
| 40 | struct tpacket_auxdata { |
| 41 | uint32_t tp_status; |
| 42 | uint32_t tp_len; |
| 43 | uint32_t tp_snaplen; |
| 44 | uint16_t tp_mac; |
| 45 | uint16_t tp_net; |
| 46 | uint16_t tp_vlan_tci; |
| 47 | uint16_t tp_padding; |
| 48 | }; |
| 49 | #endif |
| 50 | |
| 51 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 52 | /* "struct client_data_t client_data" is in bb_common_bufsiz1 */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 53 | |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 54 | |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 55 | #if ENABLE_LONG_OPTS |
| 56 | static const char udhcpc_longopts[] ALIGN1 = |
| 57 | "clientid-none\0" No_argument "C" |
| 58 | "vendorclass\0" Required_argument "V" |
| 59 | "hostname\0" Required_argument "H" |
| 60 | "fqdn\0" Required_argument "F" |
| 61 | "interface\0" Required_argument "i" |
| 62 | "now\0" No_argument "n" |
| 63 | "pidfile\0" Required_argument "p" |
| 64 | "quit\0" No_argument "q" |
| 65 | "release\0" No_argument "R" |
| 66 | "request\0" Required_argument "r" |
| 67 | "script\0" Required_argument "s" |
| 68 | "timeout\0" Required_argument "T" |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 69 | "retries\0" Required_argument "t" |
| 70 | "tryagain\0" Required_argument "A" |
| 71 | "syslog\0" No_argument "S" |
| 72 | "request-option\0" Required_argument "O" |
| 73 | "no-default-options\0" No_argument "o" |
| 74 | "foreground\0" No_argument "f" |
Denys Vlasenko | ed820cc | 2017-05-08 15:11:02 +0200 | [diff] [blame] | 75 | USE_FOR_MMU( |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 76 | "background\0" No_argument "b" |
Denys Vlasenko | ed820cc | 2017-05-08 15:11:02 +0200 | [diff] [blame] | 77 | ) |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 78 | "broadcast\0" No_argument "B" |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 79 | IF_FEATURE_UDHCPC_ARPING("arping\0" Optional_argument "a") |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 80 | IF_FEATURE_UDHCP_PORT("client-port\0" Required_argument "P") |
| 81 | ; |
| 82 | #endif |
| 83 | /* Must match getopt32 option string order */ |
| 84 | enum { |
| 85 | OPT_C = 1 << 0, |
| 86 | OPT_V = 1 << 1, |
| 87 | OPT_H = 1 << 2, |
| 88 | OPT_h = 1 << 3, |
| 89 | OPT_F = 1 << 4, |
| 90 | OPT_i = 1 << 5, |
| 91 | OPT_n = 1 << 6, |
| 92 | OPT_p = 1 << 7, |
| 93 | OPT_q = 1 << 8, |
| 94 | OPT_R = 1 << 9, |
| 95 | OPT_r = 1 << 10, |
| 96 | OPT_s = 1 << 11, |
| 97 | OPT_T = 1 << 12, |
| 98 | OPT_t = 1 << 13, |
| 99 | OPT_S = 1 << 14, |
| 100 | OPT_A = 1 << 15, |
| 101 | OPT_O = 1 << 16, |
| 102 | OPT_o = 1 << 17, |
| 103 | OPT_x = 1 << 18, |
| 104 | OPT_f = 1 << 19, |
| 105 | OPT_B = 1 << 20, |
| 106 | /* The rest has variable bit positions, need to be clever */ |
| 107 | OPTBIT_B = 20, |
| 108 | USE_FOR_MMU( OPTBIT_b,) |
| 109 | IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,) |
| 110 | IF_FEATURE_UDHCP_PORT( OPTBIT_P,) |
| 111 | USE_FOR_MMU( OPT_b = 1 << OPTBIT_b,) |
| 112 | IF_FEATURE_UDHCPC_ARPING(OPT_a = 1 << OPTBIT_a,) |
| 113 | IF_FEATURE_UDHCP_PORT( OPT_P = 1 << OPTBIT_P,) |
| 114 | }; |
| 115 | |
| 116 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 117 | /*** Script execution code ***/ |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 118 | struct dhcp_optitem { |
| 119 | unsigned len; |
| 120 | uint8_t code; |
| 121 | uint8_t malloced; |
| 122 | uint8_t *data; |
| 123 | char *env; |
| 124 | }; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 125 | |
| 126 | /* get a rough idea of how long an option will be (rounding up...) */ |
Denys Vlasenko | 3e134eb | 2016-04-22 18:09:21 +0200 | [diff] [blame] | 127 | static const uint8_t len_of_option_as_string[] ALIGN1 = { |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 128 | [OPTION_IP ] = sizeof("255.255.255.255 "), |
| 129 | [OPTION_IP_PAIR ] = sizeof("255.255.255.255 ") * 2, |
| 130 | [OPTION_STATIC_ROUTES ] = sizeof("255.255.255.255/32 255.255.255.255 "), |
Denys Vlasenko | 352f79a | 2016-02-26 15:54:56 +0100 | [diff] [blame] | 131 | [OPTION_6RD ] = sizeof("132 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 "), |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 132 | [OPTION_STRING ] = 1, |
Denys Vlasenko | d2266d4 | 2012-04-22 03:37:01 +0200 | [diff] [blame] | 133 | [OPTION_STRING_HOST ] = 1, |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 134 | #if ENABLE_FEATURE_UDHCP_RFC3397 |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 135 | [OPTION_DNS_STRING ] = 1, /* unused */ |
| 136 | /* Hmmm, this severely overestimates size if SIP_SERVERS option |
| 137 | * is in domain name form: N-byte option in binary form |
| 138 | * mallocs ~16*N bytes. But it is freed almost at once. |
| 139 | */ |
| 140 | [OPTION_SIP_SERVERS ] = sizeof("255.255.255.255 "), |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 141 | #endif |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 142 | // [OPTION_BOOLEAN ] = sizeof("yes "), |
| 143 | [OPTION_U8 ] = sizeof("255 "), |
| 144 | [OPTION_U16 ] = sizeof("65535 "), |
| 145 | // [OPTION_S16 ] = sizeof("-32768 "), |
| 146 | [OPTION_U32 ] = sizeof("4294967295 "), |
| 147 | [OPTION_S32 ] = sizeof("-2147483684 "), |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 148 | }; |
| 149 | |
| 150 | /* note: ip is a pointer to an IP in network order, possibly misaliged */ |
| 151 | static int sprint_nip(char *dest, const char *pre, const uint8_t *ip) |
| 152 | { |
| 153 | return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]); |
| 154 | } |
| 155 | |
| 156 | /* really simple implementation, just count the bits */ |
| 157 | static int mton(uint32_t mask) |
| 158 | { |
| 159 | int i = 0; |
| 160 | mask = ntohl(mask); /* 111110000-like bit pattern */ |
| 161 | while (mask) { |
| 162 | i++; |
| 163 | mask <<= 1; |
| 164 | } |
| 165 | return i; |
| 166 | } |
| 167 | |
Denys Vlasenko | 85090c1 | 2014-06-16 00:17:00 +0200 | [diff] [blame] | 168 | #if ENABLE_FEATURE_UDHCPC_SANITIZEOPT |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 169 | /* Check if a given name represents a valid DNS name */ |
| 170 | /* See RFC1035, 2.3.1 */ |
Martin Lewis | 726d0d1 | 2020-05-04 16:59:14 -0500 | [diff] [blame] | 171 | /* We don't need to be particularly anal. For example, allowing _, hyphen |
| 172 | * at the end, or leading and trailing dots would be ok, since it |
| 173 | * can't be used for attacks. (Leading hyphen can be, if someone uses cmd "$hostname" |
| 174 | * in the script: then hostname may be treated as an option) |
| 175 | */ |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 176 | static int good_hostname(const char *name) |
| 177 | { |
Martin Lewis | 726d0d1 | 2020-05-04 16:59:14 -0500 | [diff] [blame] | 178 | if (*name == '-') /* Can't start with '-' */ |
| 179 | return 0; |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 180 | |
Martin Lewis | 726d0d1 | 2020-05-04 16:59:14 -0500 | [diff] [blame] | 181 | while (*name) { |
| 182 | unsigned char ch = *name++; |
| 183 | if (!isalnum(ch)) |
| 184 | /* DNS allows only '-', but we are more permissive */ |
| 185 | if (ch != '-' && ch != '_' && ch != '.') |
| 186 | return 0; |
| 187 | // TODO: do we want to validate lengths against NS_MAXLABEL and NS_MAXDNAME? |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 188 | } |
Martin Lewis | 726d0d1 | 2020-05-04 16:59:14 -0500 | [diff] [blame] | 189 | return 1; |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 190 | } |
Denys Vlasenko | 85090c1 | 2014-06-16 00:17:00 +0200 | [diff] [blame] | 191 | #else |
| 192 | # define good_hostname(name) 1 |
| 193 | #endif |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 194 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 195 | /* Create "opt_name=opt_value" string */ |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 196 | static NOINLINE char *xmalloc_optname_optval(const struct dhcp_optitem *opt_item, const struct dhcp_optflag *optflag, const char *opt_name) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 197 | { |
| 198 | unsigned upper_length; |
| 199 | int len, type, optlen; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 200 | char *dest, *ret; |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 201 | uint8_t *option; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 202 | |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 203 | option = opt_item->data; |
| 204 | len = opt_item->len; |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 205 | type = optflag->flags & OPTION_TYPE_MASK; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 206 | optlen = dhcp_option_lengths[type]; |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 207 | upper_length = len_of_option_as_string[type] |
Denys Vlasenko | 352f79a | 2016-02-26 15:54:56 +0100 | [diff] [blame] | 208 | * ((unsigned)(len + optlen) / (unsigned)optlen); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 209 | |
| 210 | dest = ret = xmalloc(upper_length + strlen(opt_name) + 2); |
| 211 | dest += sprintf(ret, "%s=", opt_name); |
| 212 | |
| 213 | while (len >= optlen) { |
| 214 | switch (type) { |
Denys Vlasenko | cd4d78f | 2011-10-20 13:21:55 +0200 | [diff] [blame] | 215 | case OPTION_IP: |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 216 | case OPTION_IP_PAIR: |
| 217 | dest += sprint_nip(dest, "", option); |
Martin Lewis | d30d1eb | 2020-06-09 16:59:54 -0500 | [diff] [blame] | 218 | if (type == OPTION_IP_PAIR) |
| 219 | dest += sprint_nip(dest, "/", option + 4); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 220 | break; |
Denys Vlasenko | a8f6b99 | 2010-03-26 08:35:24 +0100 | [diff] [blame] | 221 | // case OPTION_BOOLEAN: |
| 222 | // dest += sprintf(dest, *option ? "yes" : "no"); |
| 223 | // break; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 224 | case OPTION_U8: |
| 225 | dest += sprintf(dest, "%u", *option); |
| 226 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 227 | // case OPTION_S16: |
| 228 | case OPTION_U16: { |
| 229 | uint16_t val_u16; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 230 | move_from_unaligned16(val_u16, option); |
| 231 | dest += sprintf(dest, "%u", ntohs(val_u16)); |
| 232 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 233 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 234 | case OPTION_S32: |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 235 | case OPTION_U32: { |
| 236 | uint32_t val_u32; |
| 237 | move_from_unaligned32(val_u32, option); |
| 238 | dest += sprintf(dest, type == OPTION_U32 ? "%lu" : "%ld", (unsigned long) ntohl(val_u32)); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 239 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 240 | } |
Denys Vlasenko | cd4d78f | 2011-10-20 13:21:55 +0200 | [diff] [blame] | 241 | /* Note: options which use 'return' instead of 'break' |
| 242 | * (for example, OPTION_STRING) skip the code which handles |
| 243 | * the case of list of options. |
| 244 | */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 245 | case OPTION_STRING: |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 246 | case OPTION_STRING_HOST: |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 247 | memcpy(dest, option, len); |
| 248 | dest[len] = '\0'; |
Denys Vlasenko | 02cf149 | 2018-08-01 13:36:36 +0200 | [diff] [blame] | 249 | //TODO: it appears option 15 DHCP_DOMAIN_NAME is often abused |
| 250 | //by DHCP admins to contain a space-separated list of domains, |
| 251 | //not one domain name (presumably, to work as list of search domains, |
| 252 | //instead of using proper option 119 DHCP_DOMAIN_SEARCH). |
| 253 | //Currently, good_hostname() balks on strings containing spaces. |
| 254 | //Do we need to allow it? Only for DHCP_DOMAIN_NAME option? |
Denys Vlasenko | 7280d20 | 2011-12-08 16:41:05 +0100 | [diff] [blame] | 255 | if (type == OPTION_STRING_HOST && !good_hostname(dest)) |
| 256 | safe_strncpy(dest, "bad", len); |
Denys Vlasenko | cd4d78f | 2011-10-20 13:21:55 +0200 | [diff] [blame] | 257 | return ret; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 258 | case OPTION_STATIC_ROUTES: { |
| 259 | /* Option binary format: |
| 260 | * mask [one byte, 0..32] |
| 261 | * ip [big endian, 0..4 bytes depending on mask] |
| 262 | * router [big endian, 4 bytes] |
| 263 | * may be repeated |
| 264 | * |
| 265 | * We convert it to a string "IP/MASK ROUTER IP2/MASK2 ROUTER2" |
| 266 | */ |
| 267 | const char *pfx = ""; |
| 268 | |
| 269 | while (len >= 1 + 4) { /* mask + 0-byte ip + router */ |
| 270 | uint32_t nip; |
| 271 | uint8_t *p; |
| 272 | unsigned mask; |
| 273 | int bytes; |
| 274 | |
| 275 | mask = *option++; |
| 276 | if (mask > 32) |
| 277 | break; |
| 278 | len--; |
| 279 | |
| 280 | nip = 0; |
| 281 | p = (void*) &nip; |
| 282 | bytes = (mask + 7) / 8; /* 0 -> 0, 1..8 -> 1, 9..16 -> 2 etc */ |
| 283 | while (--bytes >= 0) { |
| 284 | *p++ = *option++; |
| 285 | len--; |
| 286 | } |
| 287 | if (len < 4) |
| 288 | break; |
| 289 | |
| 290 | /* print ip/mask */ |
| 291 | dest += sprint_nip(dest, pfx, (void*) &nip); |
| 292 | pfx = " "; |
| 293 | dest += sprintf(dest, "/%u ", mask); |
| 294 | /* print router */ |
| 295 | dest += sprint_nip(dest, "", option); |
| 296 | option += 4; |
| 297 | len -= 4; |
| 298 | } |
| 299 | |
| 300 | return ret; |
| 301 | } |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 302 | case OPTION_6RD: |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 303 | /* Option binary format (see RFC 5969): |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 304 | * 0 1 2 3 |
| 305 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 306 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 307 | * | OPTION_6RD | option-length | IPv4MaskLen | 6rdPrefixLen | |
| 308 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 309 | * | 6rdPrefix | |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 310 | * ... (16 octets) ... |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 311 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 312 | * ... 6rdBRIPv4Address(es) ... |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 313 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 314 | * We convert it to a string |
| 315 | * "IPv4MaskLen 6rdPrefixLen 6rdPrefix 6rdBRIPv4Address..." |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 316 | * |
| 317 | * Sanity check: ensure that our length is at least 22 bytes, that |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 318 | * IPv4MaskLen <= 32, |
| 319 | * 6rdPrefixLen <= 128, |
| 320 | * 6rdPrefixLen + (32 - IPv4MaskLen) <= 128 |
Martin Lewis | d30d1eb | 2020-06-09 16:59:54 -0500 | [diff] [blame] | 321 | * (2nd condition needs no check - it follows from 1st and 3rd). |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 322 | * Else, return envvar with empty value ("optname=") |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 323 | */ |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 324 | if (len >= (1 + 1 + 16 + 4) |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 325 | && option[0] <= 32 |
| 326 | && (option[1] + 32 - option[0]) <= 128 |
| 327 | ) { |
| 328 | /* IPv4MaskLen */ |
| 329 | dest += sprintf(dest, "%u ", *option++); |
| 330 | /* 6rdPrefixLen */ |
| 331 | dest += sprintf(dest, "%u ", *option++); |
| 332 | /* 6rdPrefix */ |
Denys Vlasenko | 42816c2 | 2011-10-20 10:52:07 +0200 | [diff] [blame] | 333 | dest += sprint_nip6(dest, /* "", */ option); |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 334 | option += 16; |
Martin Lewis | d30d1eb | 2020-06-09 16:59:54 -0500 | [diff] [blame] | 335 | len -= 1 + 1 + 16; |
| 336 | *dest++ = ' '; |
| 337 | /* 6rdBRIPv4Address(es), use common IPv4 logic to process them */ |
| 338 | type = OPTION_IP; |
| 339 | optlen = 4; |
| 340 | continue; |
Denys Vlasenko | 1f56e51 | 2011-10-19 22:40:35 +0200 | [diff] [blame] | 341 | } |
| 342 | |
| 343 | return ret; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 344 | #if ENABLE_FEATURE_UDHCP_RFC3397 |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 345 | case OPTION_DNS_STRING: |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 346 | /* unpack option into dest; use ret for prefix (i.e., "optname=") */ |
| 347 | dest = dname_dec(option, len, ret); |
| 348 | if (dest) { |
| 349 | free(ret); |
| 350 | return dest; |
| 351 | } |
| 352 | /* error. return "optname=" string */ |
| 353 | return ret; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 354 | case OPTION_SIP_SERVERS: |
| 355 | /* Option binary format: |
| 356 | * type: byte |
| 357 | * type=0: domain names, dns-compressed |
| 358 | * type=1: IP addrs |
| 359 | */ |
| 360 | option++; |
| 361 | len--; |
Martin Lewis | d30d1eb | 2020-06-09 16:59:54 -0500 | [diff] [blame] | 362 | if (option[-1] == 1) { |
| 363 | /* use common IPv4 logic to process IP addrs */ |
| 364 | type = OPTION_IP; |
| 365 | optlen = 4; |
| 366 | continue; |
| 367 | } |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 368 | if (option[-1] == 0) { |
| 369 | dest = dname_dec(option, len, ret); |
| 370 | if (dest) { |
| 371 | free(ret); |
| 372 | return dest; |
| 373 | } |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 374 | } |
| 375 | return ret; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 376 | #endif |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 377 | } /* switch */ |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 378 | |
| 379 | /* If we are here, try to format any remaining data |
| 380 | * in the option as another, similarly-formatted option |
| 381 | */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 382 | option += optlen; |
| 383 | len -= optlen; |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 384 | // TODO: it can be a list only if (optflag->flags & OPTION_LIST). |
| 385 | // Should we bail out/warn if we see multi-ip option which is |
| 386 | // not allowed to be such (for example, DHCP_BROADCAST)? - |
Denys Vlasenko | cd4d78f | 2011-10-20 13:21:55 +0200 | [diff] [blame] | 387 | if (len < optlen /* || !(optflag->flags & OPTION_LIST) */) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 388 | break; |
| 389 | *dest++ = ' '; |
| 390 | *dest = '\0'; |
Denys Vlasenko | 1dff672 | 2011-10-20 12:29:18 +0200 | [diff] [blame] | 391 | } /* while */ |
| 392 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 393 | return ret; |
| 394 | } |
| 395 | |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 396 | static void optitem_unset_env_and_free(void *item) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 397 | { |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 398 | struct dhcp_optitem *opt_item = item; |
| 399 | bb_unsetenv_and_free(opt_item->env); |
| 400 | if (opt_item->malloced) |
| 401 | free(opt_item->data); |
| 402 | free(opt_item); |
| 403 | } |
| 404 | |
| 405 | /* Used by static options (interface, siaddr, etc) */ |
| 406 | static void putenvp(char *new_opt) |
| 407 | { |
| 408 | struct dhcp_optitem *opt_item; |
| 409 | |
| 410 | opt_item = xzalloc(sizeof(*opt_item)); |
| 411 | /* opt_item->code = 0, so it won't appear in concat_option's lookup */ |
| 412 | /* opt_item->malloced = 0 */ |
| 413 | /* opt_item->data = NULL */ |
| 414 | opt_item->env = new_opt; |
| 415 | llist_add_to(&client_data.envp, opt_item); |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 416 | log2(" %s", new_opt); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 417 | putenv(new_opt); |
| 418 | } |
| 419 | |
| 420 | /* Support RFC3396 Long Encoded Options */ |
| 421 | static struct dhcp_optitem *concat_option(uint8_t *data, uint8_t len, uint8_t code) |
| 422 | { |
| 423 | llist_t *item; |
| 424 | struct dhcp_optitem *opt_item; |
| 425 | |
| 426 | /* Check if an option with the code already exists. |
| 427 | * A possible optimization is to create a bitmap of all existing options in the packet, |
| 428 | * and iterate over the option list only if they exist. |
| 429 | * This will result in bigger code, and because dhcp packets don't have too many options it |
| 430 | * shouldn't have a big impact on performance. |
| 431 | */ |
| 432 | for (item = client_data.envp; item != NULL; item = item->link) { |
| 433 | opt_item = (struct dhcp_optitem *)item->data; |
| 434 | if (opt_item->code == code) { |
| 435 | /* This option was seen already, concatenate */ |
| 436 | uint8_t *new_data; |
| 437 | |
| 438 | new_data = xmalloc(len + opt_item->len); |
| 439 | memcpy( |
| 440 | mempcpy(new_data, opt_item->data, opt_item->len), |
| 441 | data, len |
| 442 | ); |
| 443 | opt_item->len += len; |
| 444 | if (opt_item->malloced) |
| 445 | free(opt_item->data); |
| 446 | opt_item->malloced = 1; |
| 447 | opt_item->data = new_data; |
| 448 | return opt_item; |
| 449 | } |
| 450 | } |
| 451 | |
| 452 | /* This is a new option, add a new dhcp_optitem to the list */ |
| 453 | opt_item = xzalloc(sizeof(*opt_item)); |
| 454 | opt_item->code = code; |
| 455 | /* opt_item->malloced = 0 */ |
| 456 | opt_item->data = data; |
| 457 | opt_item->len = len; |
| 458 | llist_add_to(&client_data.envp, opt_item); |
| 459 | return opt_item; |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 460 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 461 | |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 462 | static const char* get_optname(uint8_t code, const struct dhcp_optflag **dh) |
| 463 | { |
| 464 | /* Find the option: |
| 465 | * dhcp_optflags is sorted so we stop searching when dh->code >= code, which is faster |
| 466 | * than iterating over the entire array. |
| 467 | * Options which don't have a match in dhcp_option_strings[], e.g DHCP_REQUESTED_IP, |
| 468 | * are located after the sorted array, so these entries will never be reached |
| 469 | * and they'll count as unknown options. |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 470 | */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 471 | for (*dh = dhcp_optflags; (*dh)->code && (*dh)->code < code; (*dh)++) |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 472 | continue; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 473 | |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 474 | if ((*dh)->code == code) |
| 475 | return nth_string(dhcp_option_strings, (*dh - dhcp_optflags)); |
| 476 | |
| 477 | return NULL; |
| 478 | } |
| 479 | |
| 480 | /* put all the parameters into the environment */ |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 481 | static void fill_envp(struct dhcp_packet *packet) |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 482 | { |
| 483 | uint8_t *optptr; |
| 484 | struct dhcp_scan_state scan_state; |
| 485 | char *new_opt; |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 486 | |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 487 | putenvp(xasprintf("interface=%s", client_data.interface)); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 488 | |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 489 | if (!packet) |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 490 | return; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 491 | |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 492 | init_scan_state(packet, &scan_state); |
| 493 | |
| 494 | /* Iterate over the packet options. |
| 495 | * Handle each option based on whether it's an unknown / known option. |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 496 | * Long options are supported in compliance with RFC 3396. |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 497 | */ |
| 498 | while ((optptr = udhcp_scan_options(packet, &scan_state)) != NULL) { |
| 499 | const struct dhcp_optflag *dh; |
| 500 | const char *opt_name; |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 501 | struct dhcp_optitem *opt_item; |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 502 | uint8_t code = optptr[OPT_CODE]; |
| 503 | uint8_t len = optptr[OPT_LEN]; |
| 504 | uint8_t *data = optptr + OPT_DATA; |
| 505 | |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 506 | opt_item = concat_option(data, len, code); |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 507 | opt_name = get_optname(code, &dh); |
| 508 | if (opt_name) { |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 509 | new_opt = xmalloc_optname_optval(opt_item, dh, opt_name); |
| 510 | if (opt_item->code == DHCP_SUBNET && opt_item->len == 4) { |
| 511 | /* Generate extra envvar for DHCP_SUBNET, $mask */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 512 | uint32_t subnet; |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 513 | move_from_unaligned32(subnet, opt_item->data); |
| 514 | putenvp(xasprintf("mask=%u", mton(subnet))); |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 515 | } |
| 516 | } else { |
| 517 | unsigned ofs; |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 518 | new_opt = xmalloc(sizeof("optNNN=") + 1 + opt_item->len*2); |
| 519 | ofs = sprintf(new_opt, "opt%u=", opt_item->code); |
| 520 | bin2hex(new_opt + ofs, (char *)opt_item->data, opt_item->len)[0] = '\0'; |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 521 | } |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 522 | log2(" %s", new_opt); |
| 523 | putenv(new_opt); |
| 524 | /* putenv will replace the existing environment variable in case of a duplicate. |
| 525 | * Free the previous occurrence (NULL if it's the first one). |
| 526 | */ |
| 527 | free(opt_item->env); |
| 528 | opt_item->env = new_opt; |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 529 | } |
| 530 | |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 531 | /* Export BOOTP fields. Fields we don't (yet?) export: |
| 532 | * uint8_t op; // always BOOTREPLY |
| 533 | * uint8_t htype; // hardware address type. 1 = 10mb ethernet |
| 534 | * uint8_t hlen; // hardware address length |
| 535 | * uint8_t hops; // used by relay agents only |
| 536 | * uint32_t xid; |
| 537 | * uint16_t secs; // elapsed since client began acquisition/renewal |
| 538 | * uint16_t flags; // only one flag so far: bcast. Never set by server |
| 539 | * uint32_t ciaddr; // client IP (usually == yiaddr. can it be different |
Brian Foley | f9beeb2 | 2016-10-25 14:20:55 +0200 | [diff] [blame] | 540 | * // if during renew server wants to give us different IP?) |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 541 | * uint8_t chaddr[16]; // link-layer client hardware address (MAC) |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 542 | */ |
| 543 | /* Most important one: yiaddr as $ip */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 544 | new_opt = xmalloc(sizeof("ip=255.255.255.255")); |
| 545 | sprint_nip(new_opt, "ip=", (uint8_t *) &packet->yiaddr); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 546 | putenvp(new_opt); |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 547 | |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 548 | if (packet->siaddr_nip) { |
| 549 | /* IP address of next server to use in bootstrap */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 550 | new_opt = xmalloc(sizeof("siaddr=255.255.255.255")); |
| 551 | sprint_nip(new_opt, "siaddr=", (uint8_t *) &packet->siaddr_nip); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 552 | putenvp(new_opt); |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 553 | } |
Martin Lewis | d378fa1 | 2019-06-10 17:06:17 +0200 | [diff] [blame] | 554 | if (packet->gateway_nip) { |
Denys Vlasenko | 84d3850 | 2019-06-13 10:02:03 +0200 | [diff] [blame] | 555 | /* IP address of DHCP relay agent */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 556 | new_opt = xmalloc(sizeof("giaddr=255.255.255.255")); |
| 557 | sprint_nip(new_opt, "giaddr=", (uint8_t *) &packet->gateway_nip); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 558 | putenvp(new_opt); |
Martin Lewis | d378fa1 | 2019-06-10 17:06:17 +0200 | [diff] [blame] | 559 | } |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 560 | if (!(scan_state.overload & FILE_FIELD) && packet->file[0]) { |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 561 | /* watch out for invalid packets */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 562 | new_opt = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 563 | putenvp(new_opt); |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 564 | } |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 565 | if (!(scan_state.overload & SNAME_FIELD) && packet->sname[0]) { |
Denys Vlasenko | fbca0c6 | 2011-10-20 14:24:18 +0200 | [diff] [blame] | 566 | /* watch out for invalid packets */ |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 567 | new_opt = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname); |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 568 | putenvp(new_opt); |
Nigel Hathaway | c37d4c6 | 2011-04-26 02:38:29 +0200 | [diff] [blame] | 569 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 570 | } |
| 571 | |
| 572 | /* Call a script with a par file and env vars */ |
| 573 | static void udhcp_run_script(struct dhcp_packet *packet, const char *name) |
| 574 | { |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 575 | char *argv[3]; |
| 576 | |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 577 | fill_envp(packet); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 578 | |
| 579 | /* call script */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 580 | log1("executing %s %s", client_data.script, name); |
| 581 | argv[0] = (char*) client_data.script; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 582 | argv[1] = (char*) name; |
| 583 | argv[2] = NULL; |
| 584 | spawn_and_wait(argv); |
| 585 | |
Martin Lewis | 1f86ecb | 2020-06-23 15:25:09 -0500 | [diff] [blame] | 586 | /* Free all allocated environment variables */ |
Martin Lewis | 9914d8b | 2020-08-04 17:27:16 -0500 | [diff] [blame] | 587 | llist_free(client_data.envp, optitem_unset_env_and_free); |
| 588 | client_data.envp = NULL; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 589 | } |
| 590 | |
| 591 | |
| 592 | /*** Sending/receiving packets ***/ |
| 593 | |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 594 | static ALWAYS_INLINE uint32_t random_xid(void) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 595 | { |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 596 | return rand(); |
| 597 | } |
| 598 | |
| 599 | /* Initialize the packet with the proper defaults */ |
| 600 | static void init_packet(struct dhcp_packet *packet, char type) |
| 601 | { |
Denys Vlasenko | 11e024a | 2019-09-24 14:01:00 +0200 | [diff] [blame] | 602 | unsigned secs; |
Denys Vlasenko | 9ac5596 | 2011-03-12 05:37:54 +0100 | [diff] [blame] | 603 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 604 | /* Fill in: op, htype, hlen, cookie fields; message type option: */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 605 | udhcp_init_header(packet, type); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 606 | |
| 607 | packet->xid = random_xid(); |
| 608 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 609 | client_data.last_secs = monotonic_sec(); |
| 610 | if (client_data.first_secs == 0) |
| 611 | client_data.first_secs = client_data.last_secs; |
| 612 | secs = client_data.last_secs - client_data.first_secs; |
Denys Vlasenko | 11e024a | 2019-09-24 14:01:00 +0200 | [diff] [blame] | 613 | packet->secs = (secs < 0xffff) ? htons(secs) : 0xffff; |
Denys Vlasenko | 9ac5596 | 2011-03-12 05:37:54 +0100 | [diff] [blame] | 614 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 615 | memcpy(packet->chaddr, client_data.client_mac, 6); |
| 616 | if (client_data.clientid) |
| 617 | udhcp_add_binary_option(packet, client_data.clientid); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 618 | } |
| 619 | |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 620 | static void add_client_options(struct dhcp_packet *packet) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 621 | { |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 622 | int i, end, len; |
| 623 | |
| 624 | udhcp_add_simple_option(packet, DHCP_MAX_SIZE, htons(IP_UDP_DHCP_SIZE)); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 625 | |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 626 | /* Add a "param req" option with the list of options we'd like to have |
Denys Vlasenko | a8f6b99 | 2010-03-26 08:35:24 +0100 | [diff] [blame] | 627 | * from stubborn DHCP servers. Pull the data from the struct in common.c. |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 628 | * No bounds checking because it goes towards the head of the packet. */ |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 629 | end = udhcp_end_option(packet->options); |
| 630 | len = 0; |
Denys Vlasenko | 293c945 | 2012-07-27 13:25:07 +0200 | [diff] [blame] | 631 | for (i = 1; i < DHCP_END; i++) { |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 632 | if (client_data.opt_mask[i >> 3] & (1 << (i & 7))) { |
Denys Vlasenko | 293c945 | 2012-07-27 13:25:07 +0200 | [diff] [blame] | 633 | packet->options[end + OPT_DATA + len] = i; |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 634 | len++; |
| 635 | } |
| 636 | } |
| 637 | if (len) { |
| 638 | packet->options[end + OPT_CODE] = DHCP_PARAM_REQ; |
| 639 | packet->options[end + OPT_LEN] = len; |
| 640 | packet->options[end + OPT_DATA + len] = DHCP_END; |
| 641 | } |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 642 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 643 | if (client_data.vendorclass) |
| 644 | udhcp_add_binary_option(packet, client_data.vendorclass); |
| 645 | if (client_data.hostname) |
| 646 | udhcp_add_binary_option(packet, client_data.hostname); |
| 647 | if (client_data.fqdn) |
| 648 | udhcp_add_binary_option(packet, client_data.fqdn); |
Denys Vlasenko | c72c1d7 | 2010-10-20 22:08:16 +0200 | [diff] [blame] | 649 | |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 650 | /* Request broadcast replies if we have no IP addr */ |
| 651 | if ((option_mask32 & OPT_B) && packet->ciaddr == 0) |
| 652 | packet->flags |= htons(BROADCAST_FLAG); |
| 653 | |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 654 | /* Add -x options if any */ |
| 655 | { |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 656 | struct option_set *curr = client_data.options; |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 657 | while (curr) { |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 658 | udhcp_add_binary_option(packet, curr->data); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 659 | curr = curr->next; |
| 660 | } |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 661 | // if (client_data.sname) |
| 662 | // strncpy((char*)packet->sname, client_data.sname, sizeof(packet->sname) - 1); |
| 663 | // if (client_data.boot_file) |
| 664 | // strncpy((char*)packet->file, client_data.boot_file, sizeof(packet->file) - 1); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 665 | } |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 666 | |
| 667 | // This will be needed if we remove -V VENDOR_STR in favor of |
| 668 | // -x vendor:VENDOR_STR |
| 669 | //if (!udhcp_find_option(packet.options, DHCP_VENDOR)) |
| 670 | // /* not set, set the default vendor ID */ |
| 671 | // ...add (DHCP_VENDOR, "udhcp "BB_VER) opt... |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 672 | } |
| 673 | |
| 674 | /* RFC 2131 |
| 675 | * 4.4.4 Use of broadcast and unicast |
| 676 | * |
| 677 | * The DHCP client broadcasts DHCPDISCOVER, DHCPREQUEST and DHCPINFORM |
| 678 | * messages, unless the client knows the address of a DHCP server. |
| 679 | * The client unicasts DHCPRELEASE messages to the server. Because |
| 680 | * the client is declining the use of the IP address supplied by the server, |
| 681 | * the client broadcasts DHCPDECLINE messages. |
| 682 | * |
| 683 | * When the DHCP client knows the address of a DHCP server, in either |
| 684 | * INIT or REBOOTING state, the client may use that address |
| 685 | * in the DHCPDISCOVER or DHCPREQUEST rather than the IP broadcast address. |
| 686 | * The client may also use unicast to send DHCPINFORM messages |
| 687 | * to a known DHCP server. If the client receives no response to DHCP |
| 688 | * messages sent to the IP address of a known DHCP server, the DHCP |
| 689 | * client reverts to using the IP broadcast address. |
| 690 | */ |
| 691 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 692 | static int raw_bcast_from_client_data_ifindex(struct dhcp_packet *packet, uint32_t src_nip) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 693 | { |
| 694 | return udhcp_send_raw_packet(packet, |
Hans Dedecker | abe8f75 | 2016-02-18 12:27:07 +0100 | [diff] [blame] | 695 | /*src*/ src_nip, CLIENT_PORT, |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 696 | /*dst*/ INADDR_BROADCAST, SERVER_PORT, MAC_BCAST_ADDR, |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 697 | client_data.ifindex); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 698 | } |
| 699 | |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 700 | static int bcast_or_ucast(struct dhcp_packet *packet, uint32_t ciaddr, uint32_t server) |
| 701 | { |
Denys Vlasenko | 148788e | 2018-06-21 17:36:22 +0200 | [diff] [blame] | 702 | if (server) |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 703 | return udhcp_send_kernel_packet(packet, |
| 704 | ciaddr, CLIENT_PORT, |
Michal Kazior | b817699 | 2020-12-15 09:53:40 +0000 | [diff] [blame] | 705 | server, SERVER_PORT, |
| 706 | client_data.interface); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 707 | return raw_bcast_from_client_data_ifindex(packet, ciaddr); |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 708 | } |
| 709 | |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 710 | /* Broadcast a DHCP discover packet to the network, with an optionally requested IP */ |
Denys Vlasenko | 0bb35e1 | 2010-10-21 12:33:10 +0200 | [diff] [blame] | 711 | /* NOINLINE: limit stack usage in caller */ |
Denys Vlasenko | c72c1d7 | 2010-10-20 22:08:16 +0200 | [diff] [blame] | 712 | static NOINLINE int send_discover(uint32_t xid, uint32_t requested) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 713 | { |
| 714 | struct dhcp_packet packet; |
| 715 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 716 | /* Fill in: op, htype, hlen, cookie, chaddr fields, |
| 717 | * random xid field (we override it below), |
| 718 | * client-id option (unless -C), message type option: |
| 719 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 720 | init_packet(&packet, DHCPDISCOVER); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 721 | |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 722 | packet.xid = xid; |
| 723 | if (requested) |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 724 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 725 | |
| 726 | /* Add options: maxsize, |
| 727 | * optionally: hostname, fqdn, vendorclass, |
| 728 | * "param req" option according to -O, options specified with -x |
| 729 | */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 730 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 731 | |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 732 | bb_simple_info_msg("broadcasting discover"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 733 | return raw_bcast_from_client_data_ifindex(&packet, INADDR_ANY); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 734 | } |
| 735 | |
| 736 | /* Broadcast a DHCP request message */ |
| 737 | /* RFC 2131 3.1 paragraph 3: |
| 738 | * "The client _broadcasts_ a DHCPREQUEST message..." |
| 739 | */ |
Denys Vlasenko | 0bb35e1 | 2010-10-21 12:33:10 +0200 | [diff] [blame] | 740 | /* NOINLINE: limit stack usage in caller */ |
Denys Vlasenko | c72c1d7 | 2010-10-20 22:08:16 +0200 | [diff] [blame] | 741 | static NOINLINE int send_select(uint32_t xid, uint32_t server, uint32_t requested) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 742 | { |
| 743 | struct dhcp_packet packet; |
Denys Vlasenko | a6a3ad3 | 2017-09-29 15:55:24 +0200 | [diff] [blame] | 744 | struct in_addr temp_addr; |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 745 | char server_str[sizeof("255.255.255.255")]; |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 746 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 747 | /* |
| 748 | * RFC 2131 4.3.2 DHCPREQUEST message |
| 749 | * ... |
| 750 | * If the DHCPREQUEST message contains a 'server identifier' |
| 751 | * option, the message is in response to a DHCPOFFER message. |
| 752 | * Otherwise, the message is a request to verify or extend an |
| 753 | * existing lease. If the client uses a 'client identifier' |
| 754 | * in a DHCPREQUEST message, it MUST use that same 'client identifier' |
| 755 | * in all subsequent messages. If the client included a list |
| 756 | * of requested parameters in a DHCPDISCOVER message, it MUST |
| 757 | * include that list in all subsequent messages. |
| 758 | */ |
| 759 | /* Fill in: op, htype, hlen, cookie, chaddr fields, |
| 760 | * random xid field (we override it below), |
| 761 | * client-id option (unless -C), message type option: |
| 762 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 763 | init_packet(&packet, DHCPREQUEST); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 764 | |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 765 | packet.xid = xid; |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 766 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 767 | |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 768 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 769 | |
| 770 | /* Add options: maxsize, |
| 771 | * optionally: hostname, fqdn, vendorclass, |
| 772 | * "param req" option according to -O, and options specified with -x |
| 773 | */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 774 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 775 | |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 776 | temp_addr.s_addr = server; |
| 777 | strcpy(server_str, inet_ntoa(temp_addr)); |
Denys Vlasenko | a6a3ad3 | 2017-09-29 15:55:24 +0200 | [diff] [blame] | 778 | temp_addr.s_addr = requested; |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 779 | bb_info_msg("broadcasting select for %s, server %s", |
| 780 | inet_ntoa(temp_addr), |
| 781 | server_str |
| 782 | ); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 783 | return raw_bcast_from_client_data_ifindex(&packet, INADDR_ANY); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 784 | } |
| 785 | |
| 786 | /* Unicast or broadcast a DHCP renew message */ |
Denys Vlasenko | 0bb35e1 | 2010-10-21 12:33:10 +0200 | [diff] [blame] | 787 | /* NOINLINE: limit stack usage in caller */ |
| 788 | static NOINLINE int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 789 | { |
| 790 | struct dhcp_packet packet; |
| 791 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 792 | /* |
| 793 | * RFC 2131 4.3.2 DHCPREQUEST message |
| 794 | * ... |
| 795 | * DHCPREQUEST generated during RENEWING state: |
| 796 | * |
| 797 | * 'server identifier' MUST NOT be filled in, 'requested IP address' |
| 798 | * option MUST NOT be filled in, 'ciaddr' MUST be filled in with |
| 799 | * client's IP address. In this situation, the client is completely |
| 800 | * configured, and is trying to extend its lease. This message will |
| 801 | * be unicast, so no relay agents will be involved in its |
| 802 | * transmission. Because 'giaddr' is therefore not filled in, the |
| 803 | * DHCP server will trust the value in 'ciaddr', and use it when |
| 804 | * replying to the client. |
| 805 | */ |
| 806 | /* Fill in: op, htype, hlen, cookie, chaddr fields, |
| 807 | * random xid field (we override it below), |
| 808 | * client-id option (unless -C), message type option: |
| 809 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 810 | init_packet(&packet, DHCPREQUEST); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 811 | |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 812 | packet.xid = xid; |
| 813 | packet.ciaddr = ciaddr; |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 814 | |
| 815 | /* Add options: maxsize, |
| 816 | * optionally: hostname, fqdn, vendorclass, |
| 817 | * "param req" option according to -O, and options specified with -x |
| 818 | */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 819 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 820 | |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 821 | if (server) { |
| 822 | struct in_addr temp_addr; |
| 823 | temp_addr.s_addr = server; |
| 824 | bb_info_msg("sending renew to server %s", inet_ntoa(temp_addr)); |
| 825 | } else { |
| 826 | bb_simple_info_msg("broadcasting renew"); |
| 827 | } |
| 828 | |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 829 | return bcast_or_ucast(&packet, ciaddr, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 830 | } |
| 831 | |
| 832 | #if ENABLE_FEATURE_UDHCPC_ARPING |
| 833 | /* Broadcast a DHCP decline message */ |
Denys Vlasenko | 0bb35e1 | 2010-10-21 12:33:10 +0200 | [diff] [blame] | 834 | /* NOINLINE: limit stack usage in caller */ |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 835 | static NOINLINE int send_decline(/*uint32_t xid,*/ uint32_t server, uint32_t requested) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 836 | { |
| 837 | struct dhcp_packet packet; |
| 838 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 839 | /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields, |
| 840 | * client-id option (unless -C), message type option: |
| 841 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 842 | init_packet(&packet, DHCPDECLINE); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 843 | |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 844 | #if 0 |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 845 | /* RFC 2131 says DHCPDECLINE's xid is randomly selected by client, |
| 846 | * but in case the server is buggy and wants DHCPDECLINE's xid |
| 847 | * to match the xid which started entire handshake, |
| 848 | * we use the same xid we used in initial DHCPDISCOVER: |
| 849 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 850 | packet.xid = xid; |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 851 | #endif |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 852 | /* DHCPDECLINE uses "requested ip", not ciaddr, to store offered IP */ |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 853 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 854 | |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 855 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 856 | |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 857 | bb_simple_info_msg("broadcasting decline"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 858 | return raw_bcast_from_client_data_ifindex(&packet, INADDR_ANY); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 859 | } |
| 860 | #endif |
| 861 | |
| 862 | /* Unicast a DHCP release message */ |
Denys Vlasenko | 9d05ad0 | 2018-11-03 23:34:03 +0100 | [diff] [blame] | 863 | static |
| 864 | ALWAYS_INLINE /* one caller, help compiler to use this fact */ |
| 865 | int send_release(uint32_t server, uint32_t ciaddr) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 866 | { |
| 867 | struct dhcp_packet packet; |
| 868 | |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 869 | /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields, |
| 870 | * client-id option (unless -C), message type option: |
| 871 | */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 872 | init_packet(&packet, DHCPRELEASE); |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 873 | |
| 874 | /* DHCPRELEASE uses ciaddr, not "requested ip", to store IP being released */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 875 | packet.ciaddr = ciaddr; |
| 876 | |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 877 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 878 | |
James Byrne | 253c4e7 | 2019-04-12 17:01:51 +0000 | [diff] [blame] | 879 | bb_info_msg("sending %s", "release"); |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 880 | /* Note: normally we unicast here since "server" is not zero. |
| 881 | * However, there _are_ people who run "address-less" DHCP servers, |
| 882 | * and reportedly ISC dhcp client and Windows allow that. |
| 883 | */ |
| 884 | return bcast_or_ucast(&packet, ciaddr, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 885 | } |
| 886 | |
| 887 | /* Returns -1 on errors that are fatal for the socket, -2 for those that aren't */ |
Denys Vlasenko | 0bb35e1 | 2010-10-21 12:33:10 +0200 | [diff] [blame] | 888 | /* NOINLINE: limit stack usage in caller */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 889 | static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd) |
| 890 | { |
| 891 | int bytes; |
| 892 | struct ip_udp_dhcp_packet packet; |
| 893 | uint16_t check; |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 894 | unsigned char cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))]; |
| 895 | struct iovec iov; |
| 896 | struct msghdr msg; |
| 897 | struct cmsghdr *cmsg; |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 898 | |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 899 | /* used to use just safe_read(fd, &packet, sizeof(packet)) |
| 900 | * but we need to check for TP_STATUS_CSUMNOTREADY :( |
| 901 | */ |
| 902 | iov.iov_base = &packet; |
| 903 | iov.iov_len = sizeof(packet); |
| 904 | memset(&msg, 0, sizeof(msg)); |
| 905 | msg.msg_iov = &iov; |
| 906 | msg.msg_iovlen = 1; |
| 907 | msg.msg_control = cmsgbuf; |
| 908 | msg.msg_controllen = sizeof(cmsgbuf); |
| 909 | for (;;) { |
| 910 | bytes = recvmsg(fd, &msg, 0); |
| 911 | if (bytes < 0) { |
| 912 | if (errno == EINTR) |
| 913 | continue; |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 914 | log1s("packet read error, ignoring"); |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 915 | /* NB: possible down interface, etc. Caller should pause. */ |
| 916 | return bytes; /* returns -1 */ |
| 917 | } |
| 918 | break; |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 919 | } |
| 920 | |
| 921 | if (bytes < (int) (sizeof(packet.ip) + sizeof(packet.udp))) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 922 | log1s("packet is too short, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 923 | return -2; |
| 924 | } |
| 925 | |
| 926 | if (bytes < ntohs(packet.ip.tot_len)) { |
| 927 | /* packet is bigger than sizeof(packet), we did partial read */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 928 | log1s("oversized packet, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 929 | return -2; |
| 930 | } |
| 931 | |
| 932 | /* ignore any extra garbage bytes */ |
| 933 | bytes = ntohs(packet.ip.tot_len); |
| 934 | |
| 935 | /* make sure its the right packet for us, and that it passes sanity checks */ |
Denys Vlasenko | 7981d79 | 2011-10-20 10:34:05 +0200 | [diff] [blame] | 936 | if (packet.ip.protocol != IPPROTO_UDP |
| 937 | || packet.ip.version != IPVERSION |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 938 | || packet.ip.ihl != (sizeof(packet.ip) >> 2) |
| 939 | || packet.udp.dest != htons(CLIENT_PORT) |
| 940 | /* || bytes > (int) sizeof(packet) - can't happen */ |
| 941 | || ntohs(packet.udp.len) != (uint16_t)(bytes - sizeof(packet.ip)) |
| 942 | ) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 943 | log1s("unrelated/bogus packet, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 944 | return -2; |
| 945 | } |
| 946 | |
| 947 | /* verify IP checksum */ |
| 948 | check = packet.ip.check; |
| 949 | packet.ip.check = 0; |
Denys Vlasenko | 4a0eb03 | 2020-10-01 03:07:22 +0200 | [diff] [blame] | 950 | if (check != inet_cksum(&packet.ip, sizeof(packet.ip))) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 951 | log1s("bad IP header checksum, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 952 | return -2; |
| 953 | } |
| 954 | |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 955 | for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) { |
| 956 | if (cmsg->cmsg_level == SOL_PACKET |
| 957 | && cmsg->cmsg_type == PACKET_AUXDATA |
| 958 | ) { |
| 959 | /* some VMs don't checksum UDP and TCP data |
| 960 | * they send to the same physical machine, |
| 961 | * here we detect this case: |
| 962 | */ |
| 963 | struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg); |
| 964 | if (aux->tp_status & TP_STATUS_CSUMNOTREADY) |
| 965 | goto skip_udp_sum_check; |
| 966 | } |
| 967 | } |
| 968 | |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 969 | /* verify UDP checksum. IP header has to be modified for this */ |
| 970 | memset(&packet.ip, 0, offsetof(struct iphdr, protocol)); |
| 971 | /* ip.xx fields which are not memset: protocol, check, saddr, daddr */ |
| 972 | packet.ip.tot_len = packet.udp.len; /* yes, this is needed */ |
| 973 | check = packet.udp.check; |
| 974 | packet.udp.check = 0; |
Denys Vlasenko | 4a0eb03 | 2020-10-01 03:07:22 +0200 | [diff] [blame] | 975 | if (check && check != inet_cksum(&packet, bytes)) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 976 | log1s("packet with bad UDP checksum received, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 977 | return -2; |
| 978 | } |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 979 | skip_udp_sum_check: |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 980 | |
Denys Vlasenko | 7981d79 | 2011-10-20 10:34:05 +0200 | [diff] [blame] | 981 | if (packet.data.cookie != htonl(DHCP_MAGIC)) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 982 | bb_simple_info_msg("packet with bad magic, ignoring"); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 983 | return -2; |
| 984 | } |
Denys Vlasenko | 7981d79 | 2011-10-20 10:34:05 +0200 | [diff] [blame] | 985 | |
Denys Vlasenko | 8f2e99c | 2016-03-30 18:41:23 +0200 | [diff] [blame] | 986 | log1("received %s", "a packet"); |
Denys Vlasenko | 7981d79 | 2011-10-20 10:34:05 +0200 | [diff] [blame] | 987 | udhcp_dump_packet(&packet.data); |
| 988 | |
| 989 | bytes -= sizeof(packet.ip) + sizeof(packet.udp); |
| 990 | memcpy(dhcp_pkt, &packet.data, bytes); |
| 991 | return bytes; |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 992 | } |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 993 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 994 | |
| 995 | /*** Main ***/ |
| 996 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 997 | /* Values for client_data.listen_mode */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 998 | #define LISTEN_NONE 0 |
| 999 | #define LISTEN_KERNEL 1 |
| 1000 | #define LISTEN_RAW 2 |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1001 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1002 | /* Values for client_data.state */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1003 | /* initial state: (re)start DHCP negotiation */ |
| 1004 | #define INIT_SELECTING 0 |
| 1005 | /* discover was sent, DHCPOFFER reply received */ |
| 1006 | #define REQUESTING 1 |
| 1007 | /* select/renew was sent, DHCPACK reply received */ |
| 1008 | #define BOUND 2 |
| 1009 | /* half of lease passed, want to renew it by sending unicast renew requests */ |
| 1010 | #define RENEWING 3 |
| 1011 | /* renew requests were not answered, lease is almost over, send broadcast renew */ |
| 1012 | #define REBINDING 4 |
| 1013 | /* manually requested renew (SIGUSR1) */ |
| 1014 | #define RENEW_REQUESTED 5 |
| 1015 | /* release, possibly manually requested (SIGUSR2) */ |
| 1016 | #define RELEASED 6 |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1017 | |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1018 | static int udhcp_raw_socket(int ifindex) |
| 1019 | { |
| 1020 | int fd; |
| 1021 | struct sockaddr_ll sock; |
| 1022 | |
Denys Vlasenko | 168f0ef | 2017-07-21 12:04:22 +0200 | [diff] [blame] | 1023 | log2("opening raw socket on ifindex %d", ifindex); |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1024 | |
| 1025 | fd = xsocket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP)); |
Denys Vlasenko | 744ee5d | 2014-02-07 17:38:52 +0100 | [diff] [blame] | 1026 | /* ^^^^^ |
| 1027 | * SOCK_DGRAM: remove link-layer headers on input (SOCK_RAW keeps them) |
| 1028 | * ETH_P_IP: want to receive only packets with IPv4 eth type |
| 1029 | */ |
Denys Vlasenko | 6eb6e6a | 2019-05-31 23:51:07 +0200 | [diff] [blame] | 1030 | log3("got raw socket fd %d", fd); |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1031 | |
Denys Vlasenko | 2b9acc6 | 2017-09-29 14:09:02 +0200 | [diff] [blame] | 1032 | memset(&sock, 0, sizeof(sock)); /* let's be deterministic */ |
Vladislav Grishenko | 713e6d7 | 2011-02-14 04:50:30 +0100 | [diff] [blame] | 1033 | sock.sll_family = AF_PACKET; |
| 1034 | sock.sll_protocol = htons(ETH_P_IP); |
| 1035 | sock.sll_ifindex = ifindex; |
Denys Vlasenko | 2b9acc6 | 2017-09-29 14:09:02 +0200 | [diff] [blame] | 1036 | /*sock.sll_hatype = ARPHRD_???;*/ |
| 1037 | /*sock.sll_pkttype = PACKET_???;*/ |
| 1038 | /*sock.sll_halen = ???;*/ |
| 1039 | /*sock.sll_addr[8] = ???;*/ |
Vladislav Grishenko | 713e6d7 | 2011-02-14 04:50:30 +0100 | [diff] [blame] | 1040 | xbind(fd, (struct sockaddr *) &sock, sizeof(sock)); |
| 1041 | |
Denys Vlasenko | e4785ca | 2014-02-03 18:03:42 +0100 | [diff] [blame] | 1042 | #if 0 /* Several users reported breakage when BPF filter is used */ |
Vladislav Grishenko | 713e6d7 | 2011-02-14 04:50:30 +0100 | [diff] [blame] | 1043 | if (CLIENT_PORT == 68) { |
| 1044 | /* Use only if standard port is in use */ |
Denys Vlasenko | e4785ca | 2014-02-03 18:03:42 +0100 | [diff] [blame] | 1045 | /* |
| 1046 | * I've selected not to see LL header, so BPF doesn't see it, too. |
| 1047 | * The filter may also pass non-IP and non-ARP packets, but we do |
| 1048 | * a more complete check when receiving the message in userspace. |
| 1049 | * |
| 1050 | * and filter shamelessly stolen from: |
| 1051 | * |
| 1052 | * http://www.flamewarmaster.de/software/dhcpclient/ |
| 1053 | * |
| 1054 | * There are a few other interesting ideas on that page (look under |
| 1055 | * "Motivation"). Use of netlink events is most interesting. Think |
| 1056 | * of various network servers listening for events and reconfiguring. |
| 1057 | * That would obsolete sending HUP signals and/or make use of restarts. |
| 1058 | * |
| 1059 | * Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>. |
| 1060 | * License: GPL v2. |
Denys Vlasenko | e4785ca | 2014-02-03 18:03:42 +0100 | [diff] [blame] | 1061 | */ |
| 1062 | static const struct sock_filter filter_instr[] = { |
| 1063 | /* load 9th byte (protocol) */ |
| 1064 | BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9), |
| 1065 | /* jump to L1 if it is IPPROTO_UDP, else to L4 */ |
| 1066 | BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 0, 6), |
| 1067 | /* L1: load halfword from offset 6 (flags and frag offset) */ |
| 1068 | BPF_STMT(BPF_LD|BPF_H|BPF_ABS, 6), |
| 1069 | /* jump to L4 if any bits in frag offset field are set, else to L2 */ |
| 1070 | BPF_JUMP(BPF_JMP|BPF_JSET|BPF_K, 0x1fff, 4, 0), |
| 1071 | /* L2: skip IP header (load index reg with header len) */ |
| 1072 | BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), |
| 1073 | /* load udp destination port from halfword[header_len + 2] */ |
| 1074 | BPF_STMT(BPF_LD|BPF_H|BPF_IND, 2), |
| 1075 | /* jump to L3 if udp dport is CLIENT_PORT, else to L4 */ |
| 1076 | BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 68, 0, 1), |
Denys Vlasenko | ffc3a93 | 2014-02-19 14:17:11 +0100 | [diff] [blame] | 1077 | /* L3: accept packet ("accept 0x7fffffff bytes") */ |
| 1078 | /* Accepting 0xffffffff works too but kernel 2.6.19 is buggy */ |
| 1079 | BPF_STMT(BPF_RET|BPF_K, 0x7fffffff), |
| 1080 | /* L4: discard packet ("accept zero bytes") */ |
Denys Vlasenko | e4785ca | 2014-02-03 18:03:42 +0100 | [diff] [blame] | 1081 | BPF_STMT(BPF_RET|BPF_K, 0), |
| 1082 | }; |
| 1083 | static const struct sock_fprog filter_prog = { |
| 1084 | .len = sizeof(filter_instr) / sizeof(filter_instr[0]), |
| 1085 | /* casting const away: */ |
| 1086 | .filter = (struct sock_filter *) filter_instr, |
| 1087 | }; |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1088 | /* Ignoring error (kernel may lack support for this) */ |
| 1089 | if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog, |
| 1090 | sizeof(filter_prog)) >= 0) |
Denys Vlasenko | 8f2e99c | 2016-03-30 18:41:23 +0200 | [diff] [blame] | 1091 | log1("attached filter to raw socket fd"); // log? |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 1092 | } |
Denys Vlasenko | e4785ca | 2014-02-03 18:03:42 +0100 | [diff] [blame] | 1093 | #endif |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 1094 | |
Denys Vlasenko | c52cbea | 2015-08-24 19:48:03 +0200 | [diff] [blame] | 1095 | if (setsockopt_1(fd, SOL_PACKET, PACKET_AUXDATA) != 0) { |
Alexey Froloff | 3c62bba | 2012-09-17 16:02:44 +0200 | [diff] [blame] | 1096 | if (errno != ENOPROTOOPT) |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1097 | log1s("can't set PACKET_AUXDATA on raw socket"); |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1098 | } |
| 1099 | |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1100 | log1s("created raw socket"); |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 1101 | |
| 1102 | return fd; |
| 1103 | } |
| 1104 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1105 | static void change_listen_mode(int new_mode) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1106 | { |
Denys Vlasenko | 8f2e99c | 2016-03-30 18:41:23 +0200 | [diff] [blame] | 1107 | log1("entering listen mode: %s", |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1108 | new_mode != LISTEN_NONE |
| 1109 | ? (new_mode == LISTEN_KERNEL ? "kernel" : "raw") |
| 1110 | : "none" |
| 1111 | ); |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 1112 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1113 | client_data.listen_mode = new_mode; |
| 1114 | if (client_data.sockfd >= 0) { |
| 1115 | close(client_data.sockfd); |
| 1116 | client_data.sockfd = -1; |
Denis Vlasenko | fbd2918 | 2007-04-07 01:05:47 +0000 | [diff] [blame] | 1117 | } |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 1118 | if (new_mode == LISTEN_KERNEL) |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1119 | client_data.sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_data.interface); |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 1120 | else if (new_mode != LISTEN_NONE) |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1121 | client_data.sockfd = udhcp_raw_socket(client_data.ifindex); |
| 1122 | /* else LISTEN_NONE: client_data.sockfd stays closed */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1123 | } |
| 1124 | |
Denys Vlasenko | 9ac5596 | 2011-03-12 05:37:54 +0100 | [diff] [blame] | 1125 | /* Called only on SIGUSR1 */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1126 | static void perform_renew(void) |
| 1127 | { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1128 | bb_simple_info_msg("performing DHCP renew"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1129 | switch (client_data.state) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1130 | case BOUND: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1131 | change_listen_mode(LISTEN_KERNEL); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1132 | case RENEWING: |
| 1133 | case REBINDING: |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1134 | client_data.state = RENEW_REQUESTED; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1135 | break; |
| 1136 | case RENEW_REQUESTED: /* impatient are we? fine, square 1 */ |
Rob Landley | 3f78561 | 2006-05-28 01:06:36 +0000 | [diff] [blame] | 1137 | udhcp_run_script(NULL, "deconfig"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1138 | case REQUESTING: |
| 1139 | case RELEASED: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1140 | change_listen_mode(LISTEN_RAW); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1141 | client_data.state = INIT_SELECTING; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1142 | break; |
| 1143 | case INIT_SELECTING: |
| 1144 | break; |
| 1145 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1146 | } |
| 1147 | |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1148 | static void perform_release(uint32_t server_addr, uint32_t requested_ip) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1149 | { |
Denis Vlasenko | 42b3dea | 2007-07-03 15:47:50 +0000 | [diff] [blame] | 1150 | char buffer[sizeof("255.255.255.255")]; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1151 | struct in_addr temp_addr; |
| 1152 | |
| 1153 | /* send release packet */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1154 | if (client_data.state == BOUND |
| 1155 | || client_data.state == RENEWING |
| 1156 | || client_data.state == REBINDING |
| 1157 | || client_data.state == RENEW_REQUESTED |
Denys Vlasenko | 44399e0 | 2016-07-03 20:26:44 +0200 | [diff] [blame] | 1158 | ) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1159 | temp_addr.s_addr = server_addr; |
Denis Vlasenko | 42b3dea | 2007-07-03 15:47:50 +0000 | [diff] [blame] | 1160 | strcpy(buffer, inet_ntoa(temp_addr)); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1161 | temp_addr.s_addr = requested_ip; |
James Byrne | 253c4e7 | 2019-04-12 17:01:51 +0000 | [diff] [blame] | 1162 | bb_info_msg("unicasting a release of %s to %s", |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1163 | inet_ntoa(temp_addr), buffer); |
| 1164 | send_release(server_addr, requested_ip); /* unicast */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1165 | } |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1166 | bb_simple_info_msg("entering released state"); |
Peter Korsgaard | b6355e2 | 2016-08-26 18:46:34 +0200 | [diff] [blame] | 1167 | /* |
| 1168 | * We can be here on: SIGUSR2, |
| 1169 | * or on exit (SIGTERM) and -R "release on quit" is specified. |
| 1170 | * Users requested to be notified in all cases, even if not in one |
| 1171 | * of the states above. |
| 1172 | */ |
| 1173 | udhcp_run_script(NULL, "deconfig"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1174 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1175 | change_listen_mode(LISTEN_NONE); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1176 | client_data.state = RELEASED; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1177 | } |
| 1178 | |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1179 | static uint8_t* alloc_dhcp_option(int code, const char *str, int extra) |
| 1180 | { |
| 1181 | uint8_t *storage; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 1182 | int len = strnlen(str, 255); |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1183 | storage = xzalloc(len + extra + OPT_DATA); |
| 1184 | storage[OPT_CODE] = code; |
| 1185 | storage[OPT_LEN] = len + extra; |
| 1186 | memcpy(storage + extra + OPT_DATA, str, len); |
| 1187 | return storage; |
| 1188 | } |
| 1189 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1190 | #if BB_MMU |
| 1191 | static void client_background(void) |
| 1192 | { |
| 1193 | bb_daemonize(0); |
| 1194 | logmode &= ~LOGMODE_STDIO; |
| 1195 | /* rewrite pidfile, as our pid is different now */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1196 | write_pidfile(client_data.pidfile); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1197 | } |
| 1198 | #endif |
| 1199 | |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1200 | //usage:#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1 |
| 1201 | //usage:# define IF_UDHCP_VERBOSE(...) __VA_ARGS__ |
| 1202 | //usage:#else |
| 1203 | //usage:# define IF_UDHCP_VERBOSE(...) |
| 1204 | //usage:#endif |
| 1205 | //usage:#define udhcpc_trivial_usage |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1206 | //usage: "[-fbq"IF_UDHCP_VERBOSE("v")"RB]"IF_FEATURE_UDHCPC_ARPING(" [-a[MSEC]]")" [-t N] [-T SEC] [-A SEC/-n]\n" |
Denys Vlasenko | 9ae6d79 | 2013-08-08 12:45:45 +0200 | [diff] [blame] | 1207 | //usage: " [-i IFACE]"IF_FEATURE_UDHCP_PORT(" [-P PORT]")" [-s PROG] [-p PIDFILE]\n" |
| 1208 | //usage: " [-oC] [-r IP] [-V VENDOR] [-F NAME] [-x OPT:VAL]... [-O OPT]..." |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1209 | //usage:#define udhcpc_full_usage "\n" |
Andre Kalb | 5f2e00f | 2020-05-05 18:24:25 +0200 | [diff] [blame] | 1210 | //usage: "\n -i IFACE Interface to use (default "CONFIG_UDHCPC_DEFAULT_INTERFACE")" |
Denys Vlasenko | 9ae6d79 | 2013-08-08 12:45:45 +0200 | [diff] [blame] | 1211 | //usage: IF_FEATURE_UDHCP_PORT( |
| 1212 | //usage: "\n -P PORT Use PORT (default 68)" |
| 1213 | //usage: ) |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1214 | //usage: "\n -s PROG Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")" |
Denys Vlasenko | 9ae6d79 | 2013-08-08 12:45:45 +0200 | [diff] [blame] | 1215 | //usage: "\n -p FILE Create pidfile" |
Keith Young | e6bb8d3 | 2011-03-07 03:18:46 +0100 | [diff] [blame] | 1216 | //usage: "\n -B Request broadcast replies" |
Denys Vlasenko | aadb485 | 2013-08-05 02:21:36 +0200 | [diff] [blame] | 1217 | //usage: "\n -t N Send up to N discover packets (default 3)" |
Denys Vlasenko | 456687f | 2013-08-08 12:33:18 +0200 | [diff] [blame] | 1218 | //usage: "\n -T SEC Pause between packets (default 3)" |
Denys Vlasenko | 9ae6d79 | 2013-08-08 12:45:45 +0200 | [diff] [blame] | 1219 | //usage: "\n -A SEC Wait if lease is not obtained (default 20)" |
Denys Vlasenko | 544143d | 2019-02-27 08:17:07 +0100 | [diff] [blame] | 1220 | //usage: USE_FOR_MMU( |
| 1221 | //usage: "\n -b Background if lease is not obtained" |
| 1222 | //usage: ) |
Denys Vlasenko | 456687f | 2013-08-08 12:33:18 +0200 | [diff] [blame] | 1223 | //usage: "\n -n Exit if lease is not obtained" |
| 1224 | //usage: "\n -q Exit after obtaining lease" |
| 1225 | //usage: "\n -R Release IP on exit" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1226 | //usage: "\n -f Run in foreground" |
Denys Vlasenko | c59e06e | 2010-10-20 16:10:59 +0200 | [diff] [blame] | 1227 | //usage: "\n -S Log to syslog too" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1228 | //usage: IF_FEATURE_UDHCPC_ARPING( |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1229 | //usage: "\n -a[MSEC] Validate offered address with ARP ping" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1230 | //usage: ) |
Denys Vlasenko | c59e06e | 2010-10-20 16:10:59 +0200 | [diff] [blame] | 1231 | //usage: "\n -r IP Request this IP address" |
Denys Vlasenko | 9ae6d79 | 2013-08-08 12:45:45 +0200 | [diff] [blame] | 1232 | //usage: "\n -o Don't request any options (unless -O is given)" |
| 1233 | //usage: "\n -O OPT Request option OPT from server (cumulative)" |
Denys Vlasenko | c59e06e | 2010-10-20 16:10:59 +0200 | [diff] [blame] | 1234 | //usage: "\n -x OPT:VAL Include option OPT in sent packets (cumulative)" |
| 1235 | //usage: "\n Examples of string, numeric, and hex byte opts:" |
| 1236 | //usage: "\n -x hostname:bbox - option 12" |
| 1237 | //usage: "\n -x lease:3600 - option 51 (lease time)" |
| 1238 | //usage: "\n -x 0x3d:0100BEEFC0FFEE - option 61 (client id)" |
Denys Vlasenko | 266f6f1 | 2018-04-13 13:18:34 +0200 | [diff] [blame] | 1239 | //usage: "\n -x 14:'\"dumpfile\"' - option 14 (shell-quoted)" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1240 | //usage: "\n -F NAME Ask server to update DNS mapping for NAME" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1241 | //usage: "\n -V VENDOR Vendor identifier (default 'udhcp VERSION')" |
Denys Vlasenko | 1cbdc03 | 2010-10-20 01:42:37 +0200 | [diff] [blame] | 1242 | //usage: "\n -C Don't send MAC as client identifier" |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1243 | //usage: IF_UDHCP_VERBOSE( |
| 1244 | //usage: "\n -v Verbose" |
| 1245 | //usage: ) |
Denys Vlasenko | 8993c3f | 2010-12-25 06:21:54 +0100 | [diff] [blame] | 1246 | //usage: "\nSignals:" |
Denys Vlasenko | 50089fc | 2011-11-07 15:44:46 +0100 | [diff] [blame] | 1247 | //usage: "\n USR1 Renew lease" |
| 1248 | //usage: "\n USR2 Release lease" |
Denys Vlasenko | 8993c3f | 2010-12-25 06:21:54 +0100 | [diff] [blame] | 1249 | |
Denys Vlasenko | 9e244c7 | 2010-10-20 01:38:56 +0200 | [diff] [blame] | 1250 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 1251 | int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Denis Vlasenko | a60f84e | 2008-07-05 09:18:54 +0000 | [diff] [blame] | 1252 | int udhcpc_main(int argc UNUSED_PARAM, char **argv) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1253 | { |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1254 | uint8_t *message; |
Denys Vlasenko | 1cbdc03 | 2010-10-20 01:42:37 +0200 | [diff] [blame] | 1255 | const char *str_V, *str_h, *str_F, *str_r; |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1256 | IF_FEATURE_UDHCPC_ARPING(const char *str_a = "2000";) |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 1257 | IF_FEATURE_UDHCP_PORT(char *str_P;) |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1258 | void *clientid_mac_ptr; |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 1259 | llist_t *list_O = NULL; |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 1260 | llist_t *list_x = NULL; |
Denis Vlasenko | 68af8e7 | 2007-11-22 21:41:14 +0000 | [diff] [blame] | 1261 | int tryagain_timeout = 20; |
| 1262 | int discover_timeout = 3; |
| 1263 | int discover_retries = 3; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 1264 | uint32_t server_addr = server_addr; /* for compiler */ |
| 1265 | uint32_t requested_ip = 0; |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 1266 | uint32_t xid = xid; /* for compiler */ |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 1267 | int packet_num; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 1268 | int timeout; /* must be signed */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1269 | int lease_remaining; /* must be signed */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1270 | unsigned opt; |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1271 | IF_FEATURE_UDHCPC_ARPING(unsigned arpping_ms;) |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1272 | int retval; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1273 | |
Denys Vlasenko | df70a43 | 2016-04-21 18:54:36 +0200 | [diff] [blame] | 1274 | setup_common_bufsiz(); |
| 1275 | |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1276 | /* Default options */ |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 1277 | IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;) |
| 1278 | IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;) |
Andre Kalb | 5f2e00f | 2020-05-05 18:24:25 +0200 | [diff] [blame] | 1279 | client_data.interface = CONFIG_UDHCPC_DEFAULT_INTERFACE; |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1280 | client_data.script = CONFIG_UDHCPC_DEFAULT_SCRIPT; |
| 1281 | client_data.sockfd = -1; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 1282 | str_V = "udhcp "BB_VER; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1283 | |
Denys Vlasenko | 65c34c5 | 2019-05-31 23:39:22 +0200 | [diff] [blame] | 1284 | /* Make sure fd 0,1,2 are open */ |
| 1285 | /* Set up the signal pipe on fds 3,4 - must be before openlog() */ |
| 1286 | udhcp_sp_setup(); |
| 1287 | |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1288 | /* Parse command line */ |
Denys Vlasenko | 22542ec | 2017-08-08 21:55:02 +0200 | [diff] [blame] | 1289 | opt = getopt32long(argv, "^" |
| 1290 | /* O,x: list; -T,-t,-A take numeric param */ |
| 1291 | "CV:H:h:F:i:np:qRr:s:T:+t:+SA:+O:*ox:*fB" |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1292 | USE_FOR_MMU("b") |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1293 | IF_FEATURE_UDHCPC_ARPING("a::") |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 1294 | IF_FEATURE_UDHCP_PORT("P:") |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1295 | "v" |
Denys Vlasenko | 22542ec | 2017-08-08 21:55:02 +0200 | [diff] [blame] | 1296 | "\0" IF_UDHCP_VERBOSE("vv") /* -v is a counter */ |
Denys Vlasenko | 036585a | 2017-08-08 16:38:18 +0200 | [diff] [blame] | 1297 | , udhcpc_longopts |
Denys Vlasenko | 1cbdc03 | 2010-10-20 01:42:37 +0200 | [diff] [blame] | 1298 | , &str_V, &str_h, &str_h, &str_F |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1299 | , &client_data.interface, &client_data.pidfile /* i,p */ |
Denys Vlasenko | 22542ec | 2017-08-08 21:55:02 +0200 | [diff] [blame] | 1300 | , &str_r /* r */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1301 | , &client_data.script /* s */ |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1302 | , &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */ |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 1303 | , &list_O |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 1304 | , &list_x |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1305 | IF_FEATURE_UDHCPC_ARPING(, &str_a) |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 1306 | IF_FEATURE_UDHCP_PORT(, &str_P) |
Leonid Lisovskiy | 6c9c0a1 | 2011-10-18 00:35:47 +0200 | [diff] [blame] | 1307 | IF_UDHCP_VERBOSE(, &dhcp_verbose) |
Denys Vlasenko | 7e21f04 | 2011-11-08 11:39:41 +0100 | [diff] [blame] | 1308 | ); |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 1309 | if (opt & (OPT_h|OPT_H)) { |
| 1310 | //msg added 2011-11 |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1311 | bb_simple_error_msg("option -h NAME is deprecated, use -x hostname:NAME"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1312 | client_data.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0); |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 1313 | } |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1314 | if (opt & OPT_F) { |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 1315 | /* FQDN option format: [0x51][len][flags][0][0]<fqdn> */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1316 | client_data.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3); |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 1317 | /* Flag bits: 0000NEOS |
| 1318 | * S: 1 = Client requests server to update A RR in DNS as well as PTR |
| 1319 | * O: 1 = Server indicates to client that DNS has been updated regardless |
| 1320 | * E: 1 = Name is in DNS format, i.e. <4>host<6>domain<3>com<0>, |
| 1321 | * not "host.domain.com". Format 0 is obsolete. |
| 1322 | * N: 1 = Client requests server to not update DNS (S must be 0 then) |
| 1323 | * Two [0] bytes which follow are deprecated and must be 0. |
| 1324 | */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1325 | client_data.fqdn[OPT_DATA + 0] = 0x1; |
| 1326 | /*client_data.fqdn[OPT_DATA + 1] = 0; - xzalloc did it */ |
| 1327 | /*client_data.fqdn[OPT_DATA + 2] = 0; */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1328 | } |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 1329 | if (opt & OPT_r) |
| 1330 | requested_ip = inet_addr(str_r); |
Denis Vlasenko | d55fe3e | 2008-02-04 13:12:16 +0000 | [diff] [blame] | 1331 | #if ENABLE_FEATURE_UDHCP_PORT |
| 1332 | if (opt & OPT_P) { |
| 1333 | CLIENT_PORT = xatou16(str_P); |
| 1334 | SERVER_PORT = CLIENT_PORT - 1; |
| 1335 | } |
| 1336 | #endif |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1337 | IF_FEATURE_UDHCPC_ARPING(arpping_ms = xatou(str_a);) |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 1338 | while (list_O) { |
Denis Vlasenko | 18c9302 | 2008-08-27 22:29:43 +0000 | [diff] [blame] | 1339 | char *optstr = llist_pop(&list_O); |
Denys Vlasenko | 5d3aace | 2011-06-04 05:07:16 +0200 | [diff] [blame] | 1340 | unsigned n = bb_strtou(optstr, NULL, 0); |
| 1341 | if (errno || n > 254) { |
Denys Vlasenko | ba4fbca | 2017-06-28 19:18:17 +0200 | [diff] [blame] | 1342 | n = udhcp_option_idx(optstr, dhcp_option_strings); |
Denys Vlasenko | 5d3aace | 2011-06-04 05:07:16 +0200 | [diff] [blame] | 1343 | n = dhcp_optflags[n].code; |
| 1344 | } |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1345 | client_data.opt_mask[n >> 3] |= 1 << (n & 7); |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 1346 | } |
Denys Vlasenko | 293c945 | 2012-07-27 13:25:07 +0200 | [diff] [blame] | 1347 | if (!(opt & OPT_o)) { |
| 1348 | unsigned i, n; |
| 1349 | for (i = 0; (n = dhcp_optflags[i].code) != 0; i++) { |
| 1350 | if (dhcp_optflags[i].flags & OPTION_REQ) { |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1351 | client_data.opt_mask[n >> 3] |= 1 << (n & 7); |
Denys Vlasenko | 293c945 | 2012-07-27 13:25:07 +0200 | [diff] [blame] | 1352 | } |
| 1353 | } |
| 1354 | } |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 1355 | while (list_x) { |
Denys Vlasenko | 266f6f1 | 2018-04-13 13:18:34 +0200 | [diff] [blame] | 1356 | char *optstr = xstrdup(llist_pop(&list_x)); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1357 | udhcp_str2optset(optstr, &client_data.options, |
Denys Vlasenko | 6027597 | 2018-05-14 11:06:35 +0200 | [diff] [blame] | 1358 | dhcp_optflags, dhcp_option_strings, |
| 1359 | /*dhcpv6:*/ 0 |
| 1360 | ); |
Denys Vlasenko | 266f6f1 | 2018-04-13 13:18:34 +0200 | [diff] [blame] | 1361 | free(optstr); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 1362 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1363 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1364 | if (udhcp_read_interface(client_data.interface, |
| 1365 | &client_data.ifindex, |
Denys Vlasenko | 26918dd | 2009-06-16 12:04:23 +0200 | [diff] [blame] | 1366 | NULL, |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1367 | client_data.client_mac) |
Denys Vlasenko | 26918dd | 2009-06-16 12:04:23 +0200 | [diff] [blame] | 1368 | ) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1369 | return 1; |
Denys Vlasenko | 26918dd | 2009-06-16 12:04:23 +0200 | [diff] [blame] | 1370 | } |
| 1371 | |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1372 | clientid_mac_ptr = NULL; |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1373 | if (!(opt & OPT_C) && !udhcp_find_option(client_data.options, DHCP_CLIENT_ID)) { |
Denys Vlasenko | 1cbdc03 | 2010-10-20 01:42:37 +0200 | [diff] [blame] | 1374 | /* not suppressed and not set, set the default client ID */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1375 | client_data.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7); |
| 1376 | client_data.clientid[OPT_DATA] = 1; /* type: ethernet */ |
| 1377 | clientid_mac_ptr = client_data.clientid + OPT_DATA+1; |
| 1378 | memcpy(clientid_mac_ptr, client_data.client_mac, 6); |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 1379 | } |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 1380 | if (str_V[0] != '\0') { |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1381 | // can drop -V, str_V, client_data.vendorclass, |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 1382 | // but need to add "vendor" to the list of recognized |
| 1383 | // string opts for this to work; |
| 1384 | // and need to tweak add_client_options() too... |
| 1385 | // ...so the question is, should we? |
| 1386 | //bb_error_msg("option -V VENDOR is deprecated, use -x vendor:VENDOR"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1387 | client_data.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0); |
Denys Vlasenko | 2017d48 | 2011-11-05 01:24:14 +0100 | [diff] [blame] | 1388 | } |
| 1389 | |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1390 | #if !BB_MMU |
| 1391 | /* on NOMMU reexec (i.e., background) early */ |
| 1392 | if (!(opt & OPT_f)) { |
| 1393 | bb_daemonize_or_rexec(0 /* flags */, argv); |
Denis Vlasenko | a19e649 | 2009-03-11 14:40:00 +0000 | [diff] [blame] | 1394 | logmode = LOGMODE_NONE; |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1395 | } |
| 1396 | #endif |
| 1397 | if (opt & OPT_S) { |
Denis Vlasenko | 5e4fda0 | 2009-03-08 23:46:48 +0000 | [diff] [blame] | 1398 | openlog(applet_name, LOG_PID, LOG_DAEMON); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1399 | logmode |= LOGMODE_SYSLOG; |
| 1400 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1401 | |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 1402 | /* Create pidfile */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1403 | write_pidfile(client_data.pidfile); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1404 | /* Goes to stdout (unless NOMMU) and possibly syslog */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1405 | bb_simple_info_msg("started, v"BB_VER); |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 1406 | /* We want random_xid to be random... */ |
| 1407 | srand(monotonic_us()); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1408 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1409 | client_data.state = INIT_SELECTING; |
Rob Landley | 3f78561 | 2006-05-28 01:06:36 +0000 | [diff] [blame] | 1410 | udhcp_run_script(NULL, "deconfig"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1411 | change_listen_mode(LISTEN_RAW); |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 1412 | packet_num = 0; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 1413 | timeout = 0; |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1414 | lease_remaining = 0; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1415 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1416 | /* Main event loop. select() waits on signal pipe and possibly |
| 1417 | * on sockfd. |
| 1418 | * "continue" statements in code below jump to the top of the loop. |
| 1419 | */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1420 | for (;;) { |
Denys Vlasenko | 52a515d | 2017-02-16 23:25:44 +0100 | [diff] [blame] | 1421 | struct pollfd pfds[2]; |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1422 | struct dhcp_packet packet; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1423 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1424 | //bb_error_msg("sockfd:%d, listen_mode:%d", client_data.sockfd, client_data.listen_mode); |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 1425 | |
| 1426 | /* Was opening raw or udp socket here |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1427 | * if (client_data.listen_mode != LISTEN_NONE && client_data.sockfd < 0), |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 1428 | * but on fast network renew responses return faster |
| 1429 | * than we open sockets. Thus this code is moved |
| 1430 | * to change_listen_mode(). Thus we open listen socket |
| 1431 | * BEFORE we send renew request (see "case BOUND:"). */ |
| 1432 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1433 | udhcp_sp_fd_set(pfds, client_data.sockfd); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1434 | |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 1435 | retval = 0; |
| 1436 | /* If we already timed out, fall through with retval = 0, else... */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1437 | if (timeout > 0) { |
| 1438 | unsigned diff; |
| 1439 | |
| 1440 | if (timeout > INT_MAX/1000) |
| 1441 | timeout = INT_MAX/1000; |
| 1442 | log1("waiting %u seconds", timeout); |
| 1443 | diff = (unsigned)monotonic_sec(); |
| 1444 | retval = poll(pfds, 2, timeout * 1000); |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1445 | if (retval < 0) { |
| 1446 | /* EINTR? A signal was caught, don't panic */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1447 | if (errno == EINTR) { |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1448 | diff = (unsigned)monotonic_sec() - diff; |
| 1449 | lease_remaining -= diff; |
| 1450 | if (lease_remaining < 0) |
| 1451 | lease_remaining = 0; |
| 1452 | timeout -= diff; |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1453 | continue; |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1454 | } |
Denys Vlasenko | 10ad622 | 2017-04-17 16:13:32 +0200 | [diff] [blame] | 1455 | /* Else: an error occurred, panic! */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1456 | bb_simple_perror_msg_and_die("poll"); |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 1457 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1458 | } |
| 1459 | |
| 1460 | /* If timeout dropped to zero, time to become active: |
| 1461 | * resend discover/renew/whatever |
| 1462 | */ |
| 1463 | if (retval == 0) { |
Denys Vlasenko | a5048fa | 2010-10-20 21:38:29 +0200 | [diff] [blame] | 1464 | /* When running on a bridge, the ifindex may have changed |
| 1465 | * (e.g. if member interfaces were added/removed |
| 1466 | * or if the status of the bridge changed). |
| 1467 | * Refresh ifindex and client_mac: |
| 1468 | */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1469 | if (udhcp_read_interface(client_data.interface, |
| 1470 | &client_data.ifindex, |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1471 | NULL, |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1472 | client_data.client_mac) |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1473 | ) { |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1474 | goto ret0; /* iface is gone? */ |
Denys Vlasenko | 5d374e9 | 2010-10-20 22:26:38 +0200 | [diff] [blame] | 1475 | } |
| 1476 | if (clientid_mac_ptr) |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1477 | memcpy(clientid_mac_ptr, client_data.client_mac, 6); |
Denys Vlasenko | a5048fa | 2010-10-20 21:38:29 +0200 | [diff] [blame] | 1478 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1479 | switch (client_data.state) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1480 | case INIT_SELECTING: |
Felix Fietkau | 1c7a58d | 2012-09-27 16:22:24 +0200 | [diff] [blame] | 1481 | if (!discover_retries || packet_num < discover_retries) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1482 | if (packet_num == 0) |
| 1483 | xid = random_xid(); |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1484 | /* broadcast */ |
| 1485 | send_discover(xid, requested_ip); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1486 | timeout = discover_timeout; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1487 | packet_num++; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1488 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1489 | } |
Denis Vlasenko | cdb0b65 | 2008-09-26 09:34:15 +0000 | [diff] [blame] | 1490 | leasefail: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1491 | udhcp_run_script(NULL, "leasefail"); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1492 | #if BB_MMU /* -b is not supported on NOMMU */ |
| 1493 | if (opt & OPT_b) { /* background if no lease */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1494 | bb_simple_info_msg("no lease, forking to background"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1495 | client_background(); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1496 | /* do not background again! */ |
Andrey Mazo | 87e2162 | 2019-02-22 16:46:19 -0500 | [diff] [blame] | 1497 | opt = ((opt & ~(OPT_b|OPT_n)) | OPT_f); |
| 1498 | /* ^^^ also disables -n (-b takes priority over -n): |
| 1499 | * ifup's default udhcpc options are -R -n, |
| 1500 | * and users want to be able to add -b |
| 1501 | * (in a config file) to make it background |
| 1502 | * _and not exit_. |
| 1503 | */ |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1504 | } else |
| 1505 | #endif |
| 1506 | if (opt & OPT_n) { /* abort if no lease */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1507 | bb_simple_info_msg("no lease, failing"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1508 | retval = 1; |
| 1509 | goto ret; |
| 1510 | } |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1511 | /* wait before trying again */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1512 | timeout = tryagain_timeout; |
| 1513 | packet_num = 0; |
| 1514 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1515 | case REQUESTING: |
Denys Vlasenko | 86d9f60 | 2016-03-04 17:00:56 +0100 | [diff] [blame] | 1516 | if (packet_num < 3) { |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1517 | /* send broadcast select packet */ |
| 1518 | send_select(xid, server_addr, requested_ip); |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1519 | timeout = discover_timeout; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1520 | packet_num++; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1521 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1522 | } |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1523 | /* Timed out, go back to init state. |
| 1524 | * "discover...select...discover..." loops |
Denis Vlasenko | 7d9399e | 2008-09-26 22:21:03 +0000 | [diff] [blame] | 1525 | * were seen in the wild. Treat them similarly |
Denis Vlasenko | cdb0b65 | 2008-09-26 09:34:15 +0000 | [diff] [blame] | 1526 | * to "no response to discover" case */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1527 | change_listen_mode(LISTEN_RAW); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1528 | client_data.state = INIT_SELECTING; |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1529 | goto leasefail; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1530 | case BOUND: |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1531 | /* 1/2 lease passed, enter renewing state */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1532 | client_data.state = RENEWING; |
| 1533 | client_data.first_secs = 0; /* make secs field count from 0 */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1534 | change_listen_mode(LISTEN_KERNEL); |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1535 | log1s("entering renew state"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1536 | /* fall right through */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1537 | case RENEW_REQUESTED: /* manual (SIGUSR1) renew */ |
| 1538 | case_RENEW_REQUESTED: |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1539 | case RENEWING: |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1540 | if (packet_num < 3) { |
| 1541 | packet_num++; |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1542 | /* send an unicast renew request */ |
| 1543 | /* Sometimes observed to fail (EADDRNOTAVAIL) to bind |
| 1544 | * a new UDP socket for sending inside send_renew. |
| 1545 | * I hazard to guess existing listening socket |
| 1546 | * is somehow conflicting with it, but why is it |
| 1547 | * not deterministic then?! Strange. |
Denys Vlasenko | 753a3ce | 2009-07-19 04:27:10 +0200 | [diff] [blame] | 1548 | * Anyway, it does recover by eventually failing through |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1549 | * into INIT_SELECTING state. |
| 1550 | */ |
Denys Vlasenko | a6a3ad3 | 2017-09-29 15:55:24 +0200 | [diff] [blame] | 1551 | if (send_renew(xid, server_addr, requested_ip) >= 0) { |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1552 | timeout = discover_timeout; |
| 1553 | /* ^^^ used to be = lease_remaining / 2 - WAY too long */ |
Denys Vlasenko | a6a3ad3 | 2017-09-29 15:55:24 +0200 | [diff] [blame] | 1554 | continue; |
| 1555 | } |
| 1556 | /* else: error sending. |
| 1557 | * example: ENETUNREACH seen with server |
| 1558 | * which gave us bogus server ID 1.1.1.1 |
| 1559 | * which wasn't reachable (and probably did not exist). |
| 1560 | */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1561 | } |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1562 | //TODO: if 3 renew's failed (no reply) but remaining lease is large, |
| 1563 | //it might make sense to make a large pause (~1 hour?) and try later? |
Denys Vlasenko | a6a3ad3 | 2017-09-29 15:55:24 +0200 | [diff] [blame] | 1564 | /* Timed out or error, enter rebinding state */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1565 | log1s("entering rebinding state"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1566 | client_data.state = REBINDING; |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1567 | /* fall right through */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1568 | case REBINDING: |
Denys Vlasenko | 219757f | 2009-10-08 23:05:46 +0200 | [diff] [blame] | 1569 | /* Switch to bcast receive */ |
| 1570 | change_listen_mode(LISTEN_RAW); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1571 | /* Lease is *really* about to run out, |
| 1572 | * try to find DHCP server using broadcast */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1573 | if (lease_remaining > 0) { |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1574 | /* send a broadcast renew request */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1575 | send_renew(xid, 0 /*INADDR_ANY*/, requested_ip); |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1576 | timeout = discover_timeout; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1577 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1578 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1579 | /* Timed out, enter init state */ |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1580 | bb_simple_info_msg("lease lost, entering init state"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1581 | udhcp_run_script(NULL, "deconfig"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1582 | client_data.state = INIT_SELECTING; |
| 1583 | client_data.first_secs = 0; /* make secs field count from 0 */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1584 | timeout = 0; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1585 | packet_num = 0; |
| 1586 | continue; |
| 1587 | /* case RELEASED: */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1588 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1589 | /* yah, I know, *you* say it would never happen */ |
| 1590 | timeout = INT_MAX; |
| 1591 | continue; /* back to main loop */ |
Denys Vlasenko | 3293bc1 | 2018-03-10 19:01:48 +0100 | [diff] [blame] | 1592 | } /* if poll timed out */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1593 | |
Denys Vlasenko | 3293bc1 | 2018-03-10 19:01:48 +0100 | [diff] [blame] | 1594 | /* poll() didn't timeout, something happened */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1595 | |
| 1596 | /* Is it a signal? */ |
Denys Vlasenko | 3293bc1 | 2018-03-10 19:01:48 +0100 | [diff] [blame] | 1597 | switch (udhcp_sp_read()) { |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1598 | case SIGUSR1: |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1599 | client_data.first_secs = 0; /* make secs field count from 0 */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1600 | perform_renew(); |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1601 | if (client_data.state == RENEW_REQUESTED) |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1602 | goto case_RENEW_REQUESTED; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1603 | /* Start things over */ |
| 1604 | packet_num = 0; |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1605 | /* Kill any timeouts, user wants this to hurry along */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1606 | timeout = 0; |
| 1607 | continue; |
| 1608 | case SIGUSR2: |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1609 | perform_release(server_addr, requested_ip); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1610 | timeout = INT_MAX; |
| 1611 | continue; |
| 1612 | case SIGTERM: |
James Byrne | 253c4e7 | 2019-04-12 17:01:51 +0000 | [diff] [blame] | 1613 | bb_info_msg("received %s", "SIGTERM"); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1614 | goto ret0; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1615 | } |
| 1616 | |
Denis Vlasenko | 739e30f | 2008-09-26 23:45:20 +0000 | [diff] [blame] | 1617 | /* Is it a packet? */ |
Denys Vlasenko | 3293bc1 | 2018-03-10 19:01:48 +0100 | [diff] [blame] | 1618 | if (!pfds[1].revents) |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1619 | continue; /* no */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1620 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1621 | { |
| 1622 | int len; |
| 1623 | |
| 1624 | /* A packet is ready, read it */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1625 | if (client_data.listen_mode == LISTEN_KERNEL) |
| 1626 | len = udhcp_recv_kernel_packet(&packet, client_data.sockfd); |
Denis Vlasenko | b76b9a4 | 2008-01-25 22:46:34 +0000 | [diff] [blame] | 1627 | else |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1628 | len = udhcp_recv_raw_packet(&packet, client_data.sockfd); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1629 | if (len == -1) { |
| 1630 | /* Error is severe, reopen socket */ |
Denys Vlasenko | 6f97b30 | 2017-09-29 18:17:25 +0200 | [diff] [blame] | 1631 | bb_error_msg("read error: "STRERROR_FMT", reopening socket" STRERROR_ERRNO); |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1632 | sleep(discover_timeout); /* 3 seconds by default */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1633 | change_listen_mode(client_data.listen_mode); /* just close and reopen */ |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1634 | } |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1635 | if (len < 0) |
| 1636 | continue; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1637 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1638 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1639 | if (packet.xid != xid) { |
Denys Vlasenko | a4959ee | 2021-02-21 16:32:07 +0100 | [diff] [blame] | 1640 | log1("xid %x (our is %x)%s", |
| 1641 | (unsigned)packet.xid, (unsigned)xid, |
| 1642 | ", ignoring packet" |
| 1643 | ); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1644 | continue; |
| 1645 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1646 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1647 | /* Ignore packets that aren't for us */ |
| 1648 | if (packet.hlen != 6 |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1649 | || memcmp(packet.chaddr, client_data.client_mac, 6) != 0 |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1650 | ) { |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1651 | //FIXME: need to also check that last 10 bytes are zero |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1652 | log1("chaddr does not match%s", ", ignoring packet"); // log2? |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1653 | continue; |
| 1654 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1655 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1656 | message = udhcp_get_option(&packet, DHCP_MESSAGE_TYPE); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1657 | if (message == NULL) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1658 | bb_info_msg("no message type option%s", ", ignoring packet"); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1659 | continue; |
| 1660 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1661 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1662 | switch (client_data.state) { |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1663 | case INIT_SELECTING: |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 1664 | /* Must be a DHCPOFFER */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1665 | if (*message == DHCPOFFER) { |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1666 | uint8_t *temp; |
| 1667 | |
Denys Vlasenko | 2af2acf | 2011-10-20 14:47:41 +0200 | [diff] [blame] | 1668 | /* What exactly is server's IP? There are several values. |
| 1669 | * Example DHCP offer captured with tchdump: |
| 1670 | * |
| 1671 | * 10.34.25.254:67 > 10.34.25.202:68 // IP header's src |
| 1672 | * BOOTP fields: |
| 1673 | * Your-IP 10.34.25.202 |
| 1674 | * Server-IP 10.34.32.125 // "next server" IP |
| 1675 | * Gateway-IP 10.34.25.254 // relay's address (if DHCP relays are in use) |
| 1676 | * DHCP options: |
| 1677 | * DHCP-Message Option 53, length 1: Offer |
| 1678 | * Server-ID Option 54, length 4: 10.34.255.7 // "server ID" |
| 1679 | * Default-Gateway Option 3, length 4: 10.34.25.254 // router |
| 1680 | * |
| 1681 | * We think that real server IP (one to use in renew/release) |
| 1682 | * is one in Server-ID option. But I am not 100% sure. |
Denys Vlasenko | ee320c6 | 2011-10-23 18:05:58 +0200 | [diff] [blame] | 1683 | * IP header's src and Gateway-IP (same in this example) |
Denys Vlasenko | 2af2acf | 2011-10-20 14:47:41 +0200 | [diff] [blame] | 1684 | * might work too. |
| 1685 | * "Next server" and router are definitely wrong ones to use, though... |
| 1686 | */ |
James Byrne | 253c4e7 | 2019-04-12 17:01:51 +0000 | [diff] [blame] | 1687 | /* We used to ignore packets without DHCP_SERVER_ID. |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 1688 | * I've got user reports from people who run "address-less" servers. |
| 1689 | * They either supply DHCP_SERVER_ID of 0.0.0.0 or don't supply it at all. |
| 1690 | * They say ISC DHCP client supports this case. |
| 1691 | */ |
| 1692 | server_addr = 0; |
Denys Vlasenko | 6d3b4bb | 2018-12-17 18:07:18 +0100 | [diff] [blame] | 1693 | temp = udhcp_get_option32(&packet, DHCP_SERVER_ID); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1694 | if (!temp) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1695 | bb_simple_info_msg("no server ID, using 0.0.0.0"); |
Denys Vlasenko | 8d3efaf | 2013-11-03 19:20:54 +0100 | [diff] [blame] | 1696 | } else { |
| 1697 | /* it IS unaligned sometimes, don't "optimize" */ |
| 1698 | move_from_unaligned32(server_addr, temp); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1699 | } |
Denys Vlasenko | b3af65b | 2010-10-20 21:37:23 +0200 | [diff] [blame] | 1700 | /*xid = packet.xid; - already is */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1701 | requested_ip = packet.yiaddr; |
| 1702 | |
| 1703 | /* enter requesting state */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1704 | client_data.state = REQUESTING; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1705 | timeout = 0; |
| 1706 | packet_num = 0; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1707 | } |
| 1708 | continue; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1709 | case REQUESTING: |
| 1710 | case RENEWING: |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1711 | case RENEW_REQUESTED: |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1712 | case REBINDING: |
| 1713 | if (*message == DHCPACK) { |
Denys Vlasenko | 2863492 | 2014-12-21 16:10:22 +0100 | [diff] [blame] | 1714 | unsigned start; |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1715 | struct in_addr temp_addr; |
Denys Vlasenko | 6448332 | 2021-02-20 18:09:54 +0100 | [diff] [blame] | 1716 | char server_str[sizeof("255.255.255.255")]; |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1717 | uint8_t *temp; |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1718 | |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1719 | temp_addr.s_addr = server_addr; |
| 1720 | strcpy(server_str, inet_ntoa(temp_addr)); |
| 1721 | temp_addr.s_addr = packet.yiaddr; |
| 1722 | |
Denys Vlasenko | 6d3b4bb | 2018-12-17 18:07:18 +0100 | [diff] [blame] | 1723 | temp = udhcp_get_option32(&packet, DHCP_LEASE_TIME); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1724 | if (!temp) { |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1725 | lease_remaining = 60 * 60; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1726 | } else { |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1727 | uint32_t lease; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1728 | /* it IS unaligned sometimes, don't "optimize" */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1729 | move_from_unaligned32(lease, temp); |
| 1730 | lease_remaining = ntohl(lease); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1731 | } |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1732 | /* Log message _before_ we sanitize lease */ |
| 1733 | bb_info_msg("lease of %s obtained from %s, lease time %u%s", |
| 1734 | inet_ntoa(temp_addr), server_str, (unsigned)lease_remaining, |
| 1735 | temp ? "" : " (default)" |
| 1736 | ); |
| 1737 | /* paranoia: must not be too small and not prone to overflows */ |
| 1738 | /* NB: 60s leases _are_ used in real world |
| 1739 | * (temporary IPs while ISP modem initializes) |
| 1740 | * do not break this case by bumplit it up. |
| 1741 | */ |
| 1742 | if (lease_remaining < 0) /* signed overflow? */ |
| 1743 | lease_remaining = INT_MAX; |
| 1744 | if (lease_remaining < 30) |
| 1745 | lease_remaining = 30; |
| 1746 | requested_ip = packet.yiaddr; |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1747 | #if ENABLE_FEATURE_UDHCPC_ARPING |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1748 | if (opt & OPT_a) { |
Denis Vlasenko | 739e30f | 2008-09-26 23:45:20 +0000 | [diff] [blame] | 1749 | /* RFC 2131 3.1 paragraph 5: |
| 1750 | * "The client receives the DHCPACK message with configuration |
| 1751 | * parameters. The client SHOULD perform a final check on the |
| 1752 | * parameters (e.g., ARP for allocated network address), and notes |
| 1753 | * the duration of the lease specified in the DHCPACK message. At this |
| 1754 | * point, the client is configured. If the client detects that the |
| 1755 | * address is already in use (e.g., through the use of ARP), |
| 1756 | * the client MUST send a DHCPDECLINE message to the server and restarts |
| 1757 | * the configuration process..." */ |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1758 | if (!arpping(requested_ip, |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1759 | NULL, |
| 1760 | (uint32_t) 0, |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1761 | client_data.client_mac, |
| 1762 | client_data.interface, |
Michel Stam | 9f41271 | 2014-10-30 11:59:04 +0100 | [diff] [blame] | 1763 | arpping_ms) |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1764 | ) { |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1765 | bb_simple_info_msg("offered address is in use " |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1766 | "(got ARP reply), declining"); |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 1767 | send_decline(/*xid,*/ server_addr, packet.yiaddr); |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1768 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1769 | if (client_data.state != REQUESTING) |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1770 | udhcp_run_script(NULL, "deconfig"); |
| 1771 | change_listen_mode(LISTEN_RAW); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1772 | client_data.state = INIT_SELECTING; |
| 1773 | client_data.first_secs = 0; /* make secs field count from 0 */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1774 | requested_ip = 0; |
| 1775 | timeout = tryagain_timeout; |
| 1776 | packet_num = 0; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1777 | continue; /* back to main loop */ |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1778 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1779 | } |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1780 | #endif |
Denys Vlasenko | 2863492 | 2014-12-21 16:10:22 +0100 | [diff] [blame] | 1781 | |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1782 | /* enter bound state */ |
Denys Vlasenko | 2863492 | 2014-12-21 16:10:22 +0100 | [diff] [blame] | 1783 | start = monotonic_sec(); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1784 | udhcp_run_script(&packet, client_data.state == REQUESTING ? "bound" : "renew"); |
Denys Vlasenko | a1a77ad | 2021-05-01 11:54:08 +0200 | [diff] [blame^] | 1785 | timeout = (unsigned)lease_remaining / 2; |
| 1786 | //TODO: why / 2? |
| 1787 | timeout -= (unsigned)monotonic_sec() - start; |
| 1788 | packet_num = 0; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1789 | |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1790 | client_data.state = BOUND; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1791 | change_listen_mode(LISTEN_NONE); |
| 1792 | if (opt & OPT_q) { /* quit after lease */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1793 | goto ret0; |
| 1794 | } |
Justin Maggard | aa369e0 | 2009-08-13 01:26:17 +0200 | [diff] [blame] | 1795 | /* future renew failures should not exit (JM) */ |
| 1796 | opt &= ~OPT_n; |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1797 | #if BB_MMU /* NOMMU case backgrounded earlier */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1798 | if (!(opt & OPT_f)) { |
| 1799 | client_background(); |
| 1800 | /* do not background again! */ |
| 1801 | opt = ((opt & ~OPT_b) | OPT_f); |
| 1802 | } |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1803 | #endif |
Denys Vlasenko | 860491c | 2011-11-18 02:09:13 +0100 | [diff] [blame] | 1804 | /* make future renew packets use different xid */ |
| 1805 | /* xid = random_xid(); ...but why bother? */ |
Denys Vlasenko | 2863492 | 2014-12-21 16:10:22 +0100 | [diff] [blame] | 1806 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1807 | continue; /* back to main loop */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1808 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1809 | if (*message == DHCPNAK) { |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1810 | /* If network has more than one DHCP server, |
| 1811 | * "wrong" server can reply first, with a NAK. |
| 1812 | * Do not interpret it as a NAK from "our" server. |
| 1813 | */ |
| 1814 | if (server_addr != 0) { |
| 1815 | uint32_t svid; |
| 1816 | uint8_t *temp; |
| 1817 | |
Denys Vlasenko | 6d3b4bb | 2018-12-17 18:07:18 +0100 | [diff] [blame] | 1818 | temp = udhcp_get_option32(&packet, DHCP_SERVER_ID); |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1819 | if (!temp) { |
| 1820 | non_matching_svid: |
Peter Korsgaard | b6355e2 | 2016-08-26 18:46:34 +0200 | [diff] [blame] | 1821 | log1("received DHCP NAK with wrong" |
James Byrne | 6937487 | 2019-07-02 11:35:03 +0200 | [diff] [blame] | 1822 | " server ID%s", ", ignoring packet"); |
Denys Vlasenko | e2318bb | 2014-02-27 18:15:50 +0100 | [diff] [blame] | 1823 | continue; |
| 1824 | } |
| 1825 | move_from_unaligned32(svid, temp); |
| 1826 | if (svid != server_addr) |
| 1827 | goto non_matching_svid; |
| 1828 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1829 | /* return to init state */ |
James Byrne | 253c4e7 | 2019-04-12 17:01:51 +0000 | [diff] [blame] | 1830 | bb_info_msg("received %s", "DHCP NAK"); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1831 | udhcp_run_script(&packet, "nak"); |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1832 | if (client_data.state != REQUESTING) |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1833 | udhcp_run_script(NULL, "deconfig"); |
| 1834 | change_listen_mode(LISTEN_RAW); |
| 1835 | sleep(3); /* avoid excessive network traffic */ |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1836 | client_data.state = INIT_SELECTING; |
| 1837 | client_data.first_secs = 0; /* make secs field count from 0 */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1838 | requested_ip = 0; |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 1839 | timeout = 0; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1840 | packet_num = 0; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1841 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1842 | continue; |
| 1843 | /* case BOUND: - ignore all packets */ |
| 1844 | /* case RELEASED: - ignore all packets */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1845 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1846 | /* back to main loop */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1847 | } /* for (;;) - main loop ends */ |
| 1848 | |
Denis Vlasenko | 6e6d331 | 2007-05-03 23:39:35 +0000 | [diff] [blame] | 1849 | ret0: |
Denys Vlasenko | 0fd4347 | 2011-11-07 00:54:27 +0100 | [diff] [blame] | 1850 | if (opt & OPT_R) /* release on quit */ |
| 1851 | perform_release(server_addr, requested_ip); |
Denis Vlasenko | 6e6d331 | 2007-05-03 23:39:35 +0000 | [diff] [blame] | 1852 | retval = 0; |
| 1853 | ret: |
Denys Vlasenko | bcb1fc3 | 2019-05-26 15:01:13 +0200 | [diff] [blame] | 1854 | /*if (client_data.pidfile) - remove_pidfile has its own check */ |
| 1855 | remove_pidfile(client_data.pidfile); |
Denis Vlasenko | 6e6d331 | 2007-05-03 23:39:35 +0000 | [diff] [blame] | 1856 | return retval; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1857 | } |