"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 | * |
| 5 | * Russ Dill <Russ.Dill@asu.edu> July 2001 |
| 6 | * |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 20 | */ |
Denis Vlasenko | af1c843 | 2007-03-26 13:22:35 +0000 | [diff] [blame] | 21 | #include <syslog.h> |
Denis Vlasenko | 1caca34 | 2007-08-02 10:14:29 +0000 | [diff] [blame] | 22 | /* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */ |
| 23 | #define WANT_PIDFILE 1 |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 24 | #include "common.h" |
| 25 | #include "dhcpd.h" |
| 26 | #include "dhcpc.h" |
Denis Vlasenko | 5a3395b | 2006-11-18 19:51:32 +0000 | [diff] [blame] | 27 | |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 28 | #include <asm/types.h> |
| 29 | #if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(_NEWLIB_VERSION) |
| 30 | # include <netpacket/packet.h> |
| 31 | # include <net/ethernet.h> |
| 32 | #else |
| 33 | # include <linux/if_packet.h> |
| 34 | # include <linux/if_ether.h> |
| 35 | #endif |
| 36 | #include <linux/filter.h> |
| 37 | |
Denis Vlasenko | deabacd | 2007-09-30 17:55:43 +0000 | [diff] [blame] | 38 | /* struct client_config_t client_config is in bb_common_bufsiz1 */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 39 | |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 40 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 41 | /*** Script execution code ***/ |
| 42 | |
| 43 | /* get a rough idea of how long an option will be (rounding up...) */ |
| 44 | static const uint8_t len_of_option_as_string[] = { |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 45 | [OPTION_IP ] = sizeof("255.255.255.255 "), |
| 46 | [OPTION_IP_PAIR ] = sizeof("255.255.255.255 ") * 2, |
| 47 | [OPTION_STATIC_ROUTES ] = sizeof("255.255.255.255/32 255.255.255.255 "), |
| 48 | [OPTION_STRING ] = 1, |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 49 | #if ENABLE_FEATURE_UDHCP_RFC3397 |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 50 | [OPTION_DNS_STRING ] = 1, /* unused */ |
| 51 | /* Hmmm, this severely overestimates size if SIP_SERVERS option |
| 52 | * is in domain name form: N-byte option in binary form |
| 53 | * mallocs ~16*N bytes. But it is freed almost at once. |
| 54 | */ |
| 55 | [OPTION_SIP_SERVERS ] = sizeof("255.255.255.255 "), |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 56 | #endif |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 57 | // [OPTION_BOOLEAN ] = sizeof("yes "), |
| 58 | [OPTION_U8 ] = sizeof("255 "), |
| 59 | [OPTION_U16 ] = sizeof("65535 "), |
| 60 | // [OPTION_S16 ] = sizeof("-32768 "), |
| 61 | [OPTION_U32 ] = sizeof("4294967295 "), |
| 62 | [OPTION_S32 ] = sizeof("-2147483684 "), |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 63 | }; |
| 64 | |
| 65 | /* note: ip is a pointer to an IP in network order, possibly misaliged */ |
| 66 | static int sprint_nip(char *dest, const char *pre, const uint8_t *ip) |
| 67 | { |
| 68 | return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]); |
| 69 | } |
| 70 | |
| 71 | /* really simple implementation, just count the bits */ |
| 72 | static int mton(uint32_t mask) |
| 73 | { |
| 74 | int i = 0; |
| 75 | mask = ntohl(mask); /* 111110000-like bit pattern */ |
| 76 | while (mask) { |
| 77 | i++; |
| 78 | mask <<= 1; |
| 79 | } |
| 80 | return i; |
| 81 | } |
| 82 | |
| 83 | /* Create "opt_name=opt_value" string */ |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 84 | static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_optflag *optflag, const char *opt_name) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 85 | { |
| 86 | unsigned upper_length; |
| 87 | int len, type, optlen; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 88 | char *dest, *ret; |
| 89 | |
| 90 | /* option points to OPT_DATA, need to go back and get OPT_LEN */ |
| 91 | len = option[OPT_LEN - OPT_DATA]; |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 92 | |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 93 | type = optflag->flags & OPTION_TYPE_MASK; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 94 | optlen = dhcp_option_lengths[type]; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 95 | upper_length = len_of_option_as_string[type] * ((unsigned)len / (unsigned)optlen); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 96 | |
| 97 | dest = ret = xmalloc(upper_length + strlen(opt_name) + 2); |
| 98 | dest += sprintf(ret, "%s=", opt_name); |
| 99 | |
| 100 | while (len >= optlen) { |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 101 | unsigned ip_ofs = 0; |
| 102 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 103 | switch (type) { |
| 104 | case OPTION_IP_PAIR: |
| 105 | dest += sprint_nip(dest, "", option); |
| 106 | *dest++ = '/'; |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 107 | ip_ofs = 4; |
| 108 | /* fall through */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 109 | case OPTION_IP: |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 110 | dest += sprint_nip(dest, "", option + ip_ofs); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 111 | break; |
Denys Vlasenko | a8f6b99 | 2010-03-26 08:35:24 +0100 | [diff] [blame] | 112 | // case OPTION_BOOLEAN: |
| 113 | // dest += sprintf(dest, *option ? "yes" : "no"); |
| 114 | // break; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 115 | case OPTION_U8: |
| 116 | dest += sprintf(dest, "%u", *option); |
| 117 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 118 | // case OPTION_S16: |
| 119 | case OPTION_U16: { |
| 120 | uint16_t val_u16; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 121 | move_from_unaligned16(val_u16, option); |
| 122 | dest += sprintf(dest, "%u", ntohs(val_u16)); |
| 123 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 124 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 125 | case OPTION_S32: |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 126 | case OPTION_U32: { |
| 127 | uint32_t val_u32; |
| 128 | move_from_unaligned32(val_u32, option); |
| 129 | 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] | 130 | break; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 131 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 132 | case OPTION_STRING: |
| 133 | memcpy(dest, option, len); |
| 134 | dest[len] = '\0'; |
| 135 | return ret; /* Short circuit this case */ |
| 136 | case OPTION_STATIC_ROUTES: { |
| 137 | /* Option binary format: |
| 138 | * mask [one byte, 0..32] |
| 139 | * ip [big endian, 0..4 bytes depending on mask] |
| 140 | * router [big endian, 4 bytes] |
| 141 | * may be repeated |
| 142 | * |
| 143 | * We convert it to a string "IP/MASK ROUTER IP2/MASK2 ROUTER2" |
| 144 | */ |
| 145 | const char *pfx = ""; |
| 146 | |
| 147 | while (len >= 1 + 4) { /* mask + 0-byte ip + router */ |
| 148 | uint32_t nip; |
| 149 | uint8_t *p; |
| 150 | unsigned mask; |
| 151 | int bytes; |
| 152 | |
| 153 | mask = *option++; |
| 154 | if (mask > 32) |
| 155 | break; |
| 156 | len--; |
| 157 | |
| 158 | nip = 0; |
| 159 | p = (void*) &nip; |
| 160 | bytes = (mask + 7) / 8; /* 0 -> 0, 1..8 -> 1, 9..16 -> 2 etc */ |
| 161 | while (--bytes >= 0) { |
| 162 | *p++ = *option++; |
| 163 | len--; |
| 164 | } |
| 165 | if (len < 4) |
| 166 | break; |
| 167 | |
| 168 | /* print ip/mask */ |
| 169 | dest += sprint_nip(dest, pfx, (void*) &nip); |
| 170 | pfx = " "; |
| 171 | dest += sprintf(dest, "/%u ", mask); |
| 172 | /* print router */ |
| 173 | dest += sprint_nip(dest, "", option); |
| 174 | option += 4; |
| 175 | len -= 4; |
| 176 | } |
| 177 | |
| 178 | return ret; |
| 179 | } |
| 180 | #if ENABLE_FEATURE_UDHCP_RFC3397 |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 181 | case OPTION_DNS_STRING: |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 182 | /* unpack option into dest; use ret for prefix (i.e., "optname=") */ |
| 183 | dest = dname_dec(option, len, ret); |
| 184 | if (dest) { |
| 185 | free(ret); |
| 186 | return dest; |
| 187 | } |
| 188 | /* error. return "optname=" string */ |
| 189 | return ret; |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 190 | case OPTION_SIP_SERVERS: |
| 191 | /* Option binary format: |
| 192 | * type: byte |
| 193 | * type=0: domain names, dns-compressed |
| 194 | * type=1: IP addrs |
| 195 | */ |
| 196 | option++; |
| 197 | len--; |
| 198 | if (option[-1] == 0) { |
| 199 | dest = dname_dec(option, len, ret); |
| 200 | if (dest) { |
| 201 | free(ret); |
| 202 | return dest; |
| 203 | } |
| 204 | } else |
| 205 | if (option[-1] == 1) { |
| 206 | const char *pfx = ""; |
| 207 | while (1) { |
| 208 | len -= 4; |
| 209 | if (len < 0) |
| 210 | break; |
| 211 | dest += sprint_nip(dest, pfx, option); |
| 212 | pfx = " "; |
| 213 | option += 4; |
| 214 | } |
| 215 | } |
| 216 | return ret; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 217 | #endif |
Denys Vlasenko | 243ddcb | 2010-04-03 17:34:52 +0200 | [diff] [blame] | 218 | } /* switch */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 219 | option += optlen; |
| 220 | len -= optlen; |
Vladislav Grishenko | ad8def2 | 2010-10-17 12:27:50 +0200 | [diff] [blame] | 221 | // TODO: it can be a list only if (optflag->flags & OPTION_LIST). |
| 222 | // Should we bail out/warn if we see multi-ip option which is |
| 223 | // not allowed to be such (for example, DHCP_BROADCAST)? - |
| 224 | if (len <= 0 /* || !(optflag->flags & OPTION_LIST) */) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 225 | break; |
| 226 | *dest++ = ' '; |
| 227 | *dest = '\0'; |
| 228 | } |
| 229 | return ret; |
| 230 | } |
| 231 | |
| 232 | /* put all the parameters into the environment */ |
| 233 | static char **fill_envp(struct dhcp_packet *packet) |
| 234 | { |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 235 | int envc; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 236 | int i; |
| 237 | char **envp, **curr; |
| 238 | const char *opt_name; |
| 239 | uint8_t *temp; |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 240 | uint8_t overload = 0; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 241 | |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 242 | /* We need 6 elements for: |
| 243 | * "interface=IFACE" |
| 244 | * "ip=N.N.N.N" from packet->yiaddr |
| 245 | * "siaddr=IP" from packet->siaddr_nip (unless 0) |
| 246 | * "boot_file=FILE" from packet->file (unless overloaded) |
| 247 | * "sname=SERVER_HOSTNAME" from packet->sname (unless overloaded) |
| 248 | * terminating NULL |
| 249 | */ |
| 250 | envc = 6; |
| 251 | /* +1 element for each option, +2 for subnet option: */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 252 | if (packet) { |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 253 | for (i = 0; dhcp_optflags[i].code; i++) { |
| 254 | if (udhcp_get_option(packet, dhcp_optflags[i].code)) { |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 255 | if (dhcp_optflags[i].code == DHCP_SUBNET) |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 256 | envc++; /* for mton */ |
| 257 | envc++; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 258 | } |
| 259 | } |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 260 | temp = udhcp_get_option(packet, DHCP_OPTION_OVERLOAD); |
| 261 | if (temp) |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 262 | overload = *temp; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 263 | } |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 264 | curr = envp = xzalloc(sizeof(char *) * envc); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 265 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 266 | *curr = xasprintf("interface=%s", client_config.interface); |
| 267 | putenv(*curr++); |
| 268 | |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 269 | if (!packet) |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 270 | return envp; |
| 271 | |
| 272 | *curr = xmalloc(sizeof("ip=255.255.255.255")); |
| 273 | sprint_nip(*curr, "ip=", (uint8_t *) &packet->yiaddr); |
| 274 | putenv(*curr++); |
| 275 | |
| 276 | opt_name = dhcp_option_strings; |
| 277 | i = 0; |
| 278 | while (*opt_name) { |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 279 | temp = udhcp_get_option(packet, dhcp_optflags[i].code); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 280 | if (!temp) |
| 281 | goto next; |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 282 | *curr = xmalloc_optname_optval(temp, &dhcp_optflags[i], opt_name); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 283 | putenv(*curr++); |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 284 | if (dhcp_optflags[i].code == DHCP_SUBNET) { |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 285 | /* Subnet option: make things like "$ip/$mask" possible */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 286 | uint32_t subnet; |
| 287 | move_from_unaligned32(subnet, temp); |
| 288 | *curr = xasprintf("mask=%d", mton(subnet)); |
| 289 | putenv(*curr++); |
| 290 | } |
| 291 | next: |
| 292 | opt_name += strlen(opt_name) + 1; |
| 293 | i++; |
| 294 | } |
| 295 | if (packet->siaddr_nip) { |
| 296 | *curr = xmalloc(sizeof("siaddr=255.255.255.255")); |
| 297 | sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip); |
| 298 | putenv(*curr++); |
| 299 | } |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 300 | if (!(overload & FILE_FIELD) && packet->file[0]) { |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 301 | /* watch out for invalid packets */ |
| 302 | *curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file); |
| 303 | putenv(*curr++); |
| 304 | } |
Denys Vlasenko | b7d19cc | 2010-05-30 23:41:23 +0200 | [diff] [blame] | 305 | if (!(overload & SNAME_FIELD) && packet->sname[0]) { |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 306 | /* watch out for invalid packets */ |
| 307 | *curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname); |
| 308 | putenv(*curr++); |
| 309 | } |
| 310 | return envp; |
| 311 | } |
| 312 | |
| 313 | /* Call a script with a par file and env vars */ |
| 314 | static void udhcp_run_script(struct dhcp_packet *packet, const char *name) |
| 315 | { |
| 316 | char **envp, **curr; |
| 317 | char *argv[3]; |
| 318 | |
| 319 | if (client_config.script == NULL) |
| 320 | return; |
| 321 | |
| 322 | envp = fill_envp(packet); |
| 323 | |
| 324 | /* call script */ |
| 325 | log1("Executing %s %s", client_config.script, name); |
| 326 | argv[0] = (char*) client_config.script; |
| 327 | argv[1] = (char*) name; |
| 328 | argv[2] = NULL; |
| 329 | spawn_and_wait(argv); |
| 330 | |
| 331 | for (curr = envp; *curr; curr++) { |
| 332 | log2(" %s", *curr); |
Denys Vlasenko | dd8adde | 2010-06-24 05:00:50 +0200 | [diff] [blame] | 333 | bb_unsetenv_and_free(*curr); |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 334 | } |
| 335 | free(envp); |
| 336 | } |
| 337 | |
| 338 | |
| 339 | /*** Sending/receiving packets ***/ |
| 340 | |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 341 | static ALWAYS_INLINE uint32_t random_xid(void) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 342 | { |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 343 | return rand(); |
| 344 | } |
| 345 | |
| 346 | /* Initialize the packet with the proper defaults */ |
| 347 | static void init_packet(struct dhcp_packet *packet, char type) |
| 348 | { |
| 349 | udhcp_init_header(packet, type); |
| 350 | memcpy(packet->chaddr, client_config.client_mac, 6); |
| 351 | if (client_config.clientid) |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 352 | udhcp_add_binary_option(packet, client_config.clientid); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 353 | if (client_config.hostname) |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 354 | udhcp_add_binary_option(packet, client_config.hostname); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 355 | if (client_config.fqdn) |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 356 | udhcp_add_binary_option(packet, client_config.fqdn); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 357 | if (type != DHCPDECLINE |
| 358 | && type != DHCPRELEASE |
| 359 | && client_config.vendorclass |
| 360 | ) { |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 361 | udhcp_add_binary_option(packet, client_config.vendorclass); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 362 | } |
| 363 | } |
| 364 | |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 365 | static void add_client_options(struct dhcp_packet *packet) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 366 | { |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 367 | /* 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] | 368 | * 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] | 369 | * No bounds checking because it goes towards the head of the packet. */ |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 370 | uint8_t c; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 371 | int end = udhcp_end_option(packet->options); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 372 | int i, len = 0; |
| 373 | |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 374 | for (i = 0; (c = dhcp_optflags[i].code) != 0; i++) { |
| 375 | if (( (dhcp_optflags[i].flags & OPTION_REQ) |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 376 | && !client_config.no_default_options |
| 377 | ) |
| 378 | || (client_config.opt_mask[c >> 3] & (1 << (c & 7))) |
| 379 | ) { |
| 380 | packet->options[end + OPT_DATA + len] = c; |
| 381 | len++; |
| 382 | } |
| 383 | } |
| 384 | if (len) { |
| 385 | packet->options[end + OPT_CODE] = DHCP_PARAM_REQ; |
| 386 | packet->options[end + OPT_LEN] = len; |
| 387 | packet->options[end + OPT_DATA + len] = DHCP_END; |
| 388 | } |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 389 | |
| 390 | /* Add -x options if any */ |
| 391 | { |
| 392 | struct option_set *curr = client_config.options; |
| 393 | while (curr) { |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 394 | udhcp_add_binary_option(packet, curr->data); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 395 | curr = curr->next; |
| 396 | } |
| 397 | // if (client_config.sname) |
| 398 | // strncpy((char*)packet->sname, client_config.sname, sizeof(packet->sname) - 1); |
| 399 | // if (client_config.boot_file) |
| 400 | // strncpy((char*)packet->file, client_config.boot_file, sizeof(packet->file) - 1); |
| 401 | } |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 402 | } |
| 403 | |
| 404 | /* RFC 2131 |
| 405 | * 4.4.4 Use of broadcast and unicast |
| 406 | * |
| 407 | * The DHCP client broadcasts DHCPDISCOVER, DHCPREQUEST and DHCPINFORM |
| 408 | * messages, unless the client knows the address of a DHCP server. |
| 409 | * The client unicasts DHCPRELEASE messages to the server. Because |
| 410 | * the client is declining the use of the IP address supplied by the server, |
| 411 | * the client broadcasts DHCPDECLINE messages. |
| 412 | * |
| 413 | * When the DHCP client knows the address of a DHCP server, in either |
| 414 | * INIT or REBOOTING state, the client may use that address |
| 415 | * in the DHCPDISCOVER or DHCPREQUEST rather than the IP broadcast address. |
| 416 | * The client may also use unicast to send DHCPINFORM messages |
| 417 | * to a known DHCP server. If the client receives no response to DHCP |
| 418 | * messages sent to the IP address of a known DHCP server, the DHCP |
| 419 | * client reverts to using the IP broadcast address. |
| 420 | */ |
| 421 | |
| 422 | static int raw_bcast_from_client_config_ifindex(struct dhcp_packet *packet) |
| 423 | { |
| 424 | return udhcp_send_raw_packet(packet, |
| 425 | /*src*/ INADDR_ANY, CLIENT_PORT, |
| 426 | /*dst*/ INADDR_BROADCAST, SERVER_PORT, MAC_BCAST_ADDR, |
| 427 | client_config.ifindex); |
| 428 | } |
| 429 | |
| 430 | /* Broadcast a DHCP discover packet to the network, with an optionally requested IP */ |
| 431 | static int send_discover(uint32_t xid, uint32_t requested) |
| 432 | { |
| 433 | struct dhcp_packet packet; |
| 434 | |
| 435 | init_packet(&packet, DHCPDISCOVER); |
| 436 | packet.xid = xid; |
| 437 | if (requested) |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 438 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 439 | /* Explicitly saying that we want RFC-compliant packets helps |
| 440 | * some buggy DHCP servers to NOT send bigger packets */ |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 441 | udhcp_add_simple_option(&packet, DHCP_MAX_SIZE, htons(576)); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 442 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 443 | |
| 444 | bb_info_msg("Sending discover..."); |
| 445 | return raw_bcast_from_client_config_ifindex(&packet); |
| 446 | } |
| 447 | |
| 448 | /* Broadcast a DHCP request message */ |
| 449 | /* RFC 2131 3.1 paragraph 3: |
| 450 | * "The client _broadcasts_ a DHCPREQUEST message..." |
| 451 | */ |
| 452 | static int send_select(uint32_t xid, uint32_t server, uint32_t requested) |
| 453 | { |
| 454 | struct dhcp_packet packet; |
| 455 | struct in_addr addr; |
| 456 | |
| 457 | init_packet(&packet, DHCPREQUEST); |
| 458 | packet.xid = xid; |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 459 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
| 460 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 461 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 462 | |
| 463 | addr.s_addr = requested; |
| 464 | bb_info_msg("Sending select for %s...", inet_ntoa(addr)); |
| 465 | return raw_bcast_from_client_config_ifindex(&packet); |
| 466 | } |
| 467 | |
| 468 | /* Unicast or broadcast a DHCP renew message */ |
| 469 | static int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr) |
| 470 | { |
| 471 | struct dhcp_packet packet; |
| 472 | |
| 473 | init_packet(&packet, DHCPREQUEST); |
| 474 | packet.xid = xid; |
| 475 | packet.ciaddr = ciaddr; |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 476 | add_client_options(&packet); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 477 | |
| 478 | bb_info_msg("Sending renew..."); |
| 479 | if (server) |
| 480 | return udhcp_send_kernel_packet(&packet, |
| 481 | ciaddr, CLIENT_PORT, |
| 482 | server, SERVER_PORT); |
| 483 | return raw_bcast_from_client_config_ifindex(&packet); |
| 484 | } |
| 485 | |
| 486 | #if ENABLE_FEATURE_UDHCPC_ARPING |
| 487 | /* Broadcast a DHCP decline message */ |
| 488 | static int send_decline(uint32_t xid, uint32_t server, uint32_t requested) |
| 489 | { |
| 490 | struct dhcp_packet packet; |
| 491 | |
| 492 | init_packet(&packet, DHCPDECLINE); |
| 493 | packet.xid = xid; |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 494 | udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested); |
| 495 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 496 | |
| 497 | bb_info_msg("Sending decline..."); |
| 498 | return raw_bcast_from_client_config_ifindex(&packet); |
| 499 | } |
| 500 | #endif |
| 501 | |
| 502 | /* Unicast a DHCP release message */ |
| 503 | static int send_release(uint32_t server, uint32_t ciaddr) |
| 504 | { |
| 505 | struct dhcp_packet packet; |
| 506 | |
| 507 | init_packet(&packet, DHCPRELEASE); |
| 508 | packet.xid = random_xid(); |
| 509 | packet.ciaddr = ciaddr; |
| 510 | |
Denys Vlasenko | 7724c76 | 2010-03-26 09:32:09 +0100 | [diff] [blame] | 511 | udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server); |
Denys Vlasenko | 501e35c | 2010-03-22 13:43:12 +0100 | [diff] [blame] | 512 | |
| 513 | bb_info_msg("Sending release..."); |
| 514 | return udhcp_send_kernel_packet(&packet, ciaddr, CLIENT_PORT, server, SERVER_PORT); |
| 515 | } |
| 516 | |
| 517 | /* Returns -1 on errors that are fatal for the socket, -2 for those that aren't */ |
| 518 | static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd) |
| 519 | { |
| 520 | int bytes; |
| 521 | struct ip_udp_dhcp_packet packet; |
| 522 | uint16_t check; |
| 523 | |
| 524 | memset(&packet, 0, sizeof(packet)); |
| 525 | bytes = safe_read(fd, &packet, sizeof(packet)); |
| 526 | if (bytes < 0) { |
| 527 | log1("Packet read error, ignoring"); |
| 528 | /* NB: possible down interface, etc. Caller should pause. */ |
| 529 | return bytes; /* returns -1 */ |
| 530 | } |
| 531 | |
| 532 | if (bytes < (int) (sizeof(packet.ip) + sizeof(packet.udp))) { |
| 533 | log1("Packet is too short, ignoring"); |
| 534 | return -2; |
| 535 | } |
| 536 | |
| 537 | if (bytes < ntohs(packet.ip.tot_len)) { |
| 538 | /* packet is bigger than sizeof(packet), we did partial read */ |
| 539 | log1("Oversized packet, ignoring"); |
| 540 | return -2; |
| 541 | } |
| 542 | |
| 543 | /* ignore any extra garbage bytes */ |
| 544 | bytes = ntohs(packet.ip.tot_len); |
| 545 | |
| 546 | /* make sure its the right packet for us, and that it passes sanity checks */ |
| 547 | if (packet.ip.protocol != IPPROTO_UDP || packet.ip.version != IPVERSION |
| 548 | || packet.ip.ihl != (sizeof(packet.ip) >> 2) |
| 549 | || packet.udp.dest != htons(CLIENT_PORT) |
| 550 | /* || bytes > (int) sizeof(packet) - can't happen */ |
| 551 | || ntohs(packet.udp.len) != (uint16_t)(bytes - sizeof(packet.ip)) |
| 552 | ) { |
| 553 | log1("Unrelated/bogus packet, ignoring"); |
| 554 | return -2; |
| 555 | } |
| 556 | |
| 557 | /* verify IP checksum */ |
| 558 | check = packet.ip.check; |
| 559 | packet.ip.check = 0; |
| 560 | if (check != udhcp_checksum(&packet.ip, sizeof(packet.ip))) { |
| 561 | log1("Bad IP header checksum, ignoring"); |
| 562 | return -2; |
| 563 | } |
| 564 | |
| 565 | /* verify UDP checksum. IP header has to be modified for this */ |
| 566 | memset(&packet.ip, 0, offsetof(struct iphdr, protocol)); |
| 567 | /* ip.xx fields which are not memset: protocol, check, saddr, daddr */ |
| 568 | packet.ip.tot_len = packet.udp.len; /* yes, this is needed */ |
| 569 | check = packet.udp.check; |
| 570 | packet.udp.check = 0; |
| 571 | if (check && check != udhcp_checksum(&packet, bytes)) { |
| 572 | log1("Packet with bad UDP checksum received, ignoring"); |
| 573 | return -2; |
| 574 | } |
| 575 | |
| 576 | memcpy(dhcp_pkt, &packet.data, bytes - (sizeof(packet.ip) + sizeof(packet.udp))); |
| 577 | |
| 578 | if (dhcp_pkt->cookie != htonl(DHCP_MAGIC)) { |
| 579 | bb_info_msg("Packet with bad magic, ignoring"); |
| 580 | return -2; |
| 581 | } |
| 582 | log1("Got valid DHCP packet"); |
| 583 | udhcp_dump_packet(dhcp_pkt); |
| 584 | return bytes - (sizeof(packet.ip) + sizeof(packet.udp)); |
| 585 | } |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 586 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 587 | |
| 588 | /*** Main ***/ |
| 589 | |
| 590 | static int sockfd = -1; |
| 591 | |
| 592 | #define LISTEN_NONE 0 |
| 593 | #define LISTEN_KERNEL 1 |
| 594 | #define LISTEN_RAW 2 |
| 595 | static smallint listen_mode; |
| 596 | |
| 597 | /* initial state: (re)start DHCP negotiation */ |
| 598 | #define INIT_SELECTING 0 |
| 599 | /* discover was sent, DHCPOFFER reply received */ |
| 600 | #define REQUESTING 1 |
| 601 | /* select/renew was sent, DHCPACK reply received */ |
| 602 | #define BOUND 2 |
| 603 | /* half of lease passed, want to renew it by sending unicast renew requests */ |
| 604 | #define RENEWING 3 |
| 605 | /* renew requests were not answered, lease is almost over, send broadcast renew */ |
| 606 | #define REBINDING 4 |
| 607 | /* manually requested renew (SIGUSR1) */ |
| 608 | #define RENEW_REQUESTED 5 |
| 609 | /* release, possibly manually requested (SIGUSR2) */ |
| 610 | #define RELEASED 6 |
| 611 | static smallint state; |
| 612 | |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 613 | static int udhcp_raw_socket(int ifindex) |
| 614 | { |
| 615 | int fd; |
| 616 | struct sockaddr_ll sock; |
| 617 | |
| 618 | /* |
| 619 | * Comment: |
| 620 | * |
| 621 | * I've selected not to see LL header, so BPF doesn't see it, too. |
| 622 | * The filter may also pass non-IP and non-ARP packets, but we do |
| 623 | * a more complete check when receiving the message in userspace. |
| 624 | * |
| 625 | * and filter shamelessly stolen from: |
| 626 | * |
| 627 | * http://www.flamewarmaster.de/software/dhcpclient/ |
| 628 | * |
| 629 | * There are a few other interesting ideas on that page (look under |
| 630 | * "Motivation"). Use of netlink events is most interesting. Think |
| 631 | * of various network servers listening for events and reconfiguring. |
| 632 | * That would obsolete sending HUP signals and/or make use of restarts. |
| 633 | * |
| 634 | * Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>. |
| 635 | * License: GPL v2. |
| 636 | * |
| 637 | * TODO: make conditional? |
| 638 | */ |
| 639 | #define SERVER_AND_CLIENT_PORTS ((67 << 16) + 68) |
| 640 | static const struct sock_filter filter_instr[] = { |
| 641 | /* check for udp */ |
| 642 | BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9), |
| 643 | BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 2, 0), /* L5, L1, is UDP? */ |
| 644 | /* ugly check for arp on ethernet-like and IPv4 */ |
| 645 | BPF_STMT(BPF_LD|BPF_W|BPF_ABS, 2), /* L1: */ |
| 646 | BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x08000604, 3, 4), /* L3, L4 */ |
| 647 | /* skip IP header */ |
| 648 | BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0), /* L5: */ |
| 649 | /* check udp source and destination ports */ |
| 650 | BPF_STMT(BPF_LD|BPF_W|BPF_IND, 0), |
| 651 | BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, SERVER_AND_CLIENT_PORTS, 0, 1), /* L3, L4 */ |
| 652 | /* returns */ |
| 653 | BPF_STMT(BPF_RET|BPF_K, 0x0fffffff ), /* L3: pass */ |
| 654 | BPF_STMT(BPF_RET|BPF_K, 0), /* L4: reject */ |
| 655 | }; |
| 656 | static const struct sock_fprog filter_prog = { |
| 657 | .len = sizeof(filter_instr) / sizeof(filter_instr[0]), |
| 658 | /* casting const away: */ |
| 659 | .filter = (struct sock_filter *) filter_instr, |
| 660 | }; |
| 661 | |
| 662 | log1("Opening raw socket on ifindex %d", ifindex); //log2? |
| 663 | |
| 664 | fd = xsocket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP)); |
| 665 | log1("Got raw socket fd %d", fd); //log2? |
| 666 | |
| 667 | if (SERVER_PORT == 67 && CLIENT_PORT == 68) { |
| 668 | /* Use only if standard ports are in use */ |
| 669 | /* Ignoring error (kernel may lack support for this) */ |
| 670 | if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog, |
| 671 | sizeof(filter_prog)) >= 0) |
| 672 | log1("Attached filter to raw socket fd %d", fd); // log? |
| 673 | } |
| 674 | |
| 675 | sock.sll_family = AF_PACKET; |
| 676 | sock.sll_protocol = htons(ETH_P_IP); |
| 677 | sock.sll_ifindex = ifindex; |
| 678 | xbind(fd, (struct sockaddr *) &sock, sizeof(sock)); |
| 679 | log1("Created raw socket"); |
| 680 | |
| 681 | return fd; |
| 682 | } |
| 683 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 684 | static void change_listen_mode(int new_mode) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 685 | { |
Denys Vlasenko | 4945ed3 | 2009-06-17 11:58:11 +0200 | [diff] [blame] | 686 | log1("Entering listen mode: %s", |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 687 | new_mode != LISTEN_NONE |
| 688 | ? (new_mode == LISTEN_KERNEL ? "kernel" : "raw") |
| 689 | : "none" |
| 690 | ); |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 691 | |
| 692 | listen_mode = new_mode; |
Denis Vlasenko | fbd2918 | 2007-04-07 01:05:47 +0000 | [diff] [blame] | 693 | if (sockfd >= 0) { |
| 694 | close(sockfd); |
| 695 | sockfd = -1; |
| 696 | } |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 697 | if (new_mode == LISTEN_KERNEL) |
| 698 | sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface); |
| 699 | else if (new_mode != LISTEN_NONE) |
| 700 | sockfd = udhcp_raw_socket(client_config.ifindex); |
Denys Vlasenko | 6b24d53 | 2010-03-22 13:42:13 +0100 | [diff] [blame] | 701 | /* else LISTEN_NONE: sockfd stays closed */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 702 | } |
| 703 | |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 704 | static void perform_renew(void) |
| 705 | { |
Denis Vlasenko | 3538b9a | 2006-09-06 18:36:50 +0000 | [diff] [blame] | 706 | bb_info_msg("Performing a DHCP renew"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 707 | switch (state) { |
| 708 | case BOUND: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 709 | change_listen_mode(LISTEN_KERNEL); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 710 | case RENEWING: |
| 711 | case REBINDING: |
| 712 | state = RENEW_REQUESTED; |
| 713 | break; |
| 714 | case RENEW_REQUESTED: /* impatient are we? fine, square 1 */ |
Rob Landley | 3f78561 | 2006-05-28 01:06:36 +0000 | [diff] [blame] | 715 | udhcp_run_script(NULL, "deconfig"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 716 | case REQUESTING: |
| 717 | case RELEASED: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 718 | change_listen_mode(LISTEN_RAW); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 719 | state = INIT_SELECTING; |
| 720 | break; |
| 721 | case INIT_SELECTING: |
| 722 | break; |
| 723 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 724 | } |
| 725 | |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 726 | static void perform_release(uint32_t requested_ip, uint32_t server_addr) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 727 | { |
Denis Vlasenko | 42b3dea | 2007-07-03 15:47:50 +0000 | [diff] [blame] | 728 | char buffer[sizeof("255.255.255.255")]; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 729 | struct in_addr temp_addr; |
| 730 | |
| 731 | /* send release packet */ |
| 732 | if (state == BOUND || state == RENEWING || state == REBINDING) { |
| 733 | temp_addr.s_addr = server_addr; |
Denis Vlasenko | 42b3dea | 2007-07-03 15:47:50 +0000 | [diff] [blame] | 734 | strcpy(buffer, inet_ntoa(temp_addr)); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 735 | temp_addr.s_addr = requested_ip; |
Denis Vlasenko | 3538b9a | 2006-09-06 18:36:50 +0000 | [diff] [blame] | 736 | bb_info_msg("Unicasting a release of %s to %s", |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 737 | inet_ntoa(temp_addr), buffer); |
| 738 | send_release(server_addr, requested_ip); /* unicast */ |
Rob Landley | 3f78561 | 2006-05-28 01:06:36 +0000 | [diff] [blame] | 739 | udhcp_run_script(NULL, "deconfig"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 740 | } |
Denis Vlasenko | 3538b9a | 2006-09-06 18:36:50 +0000 | [diff] [blame] | 741 | bb_info_msg("Entering released state"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 742 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 743 | change_listen_mode(LISTEN_NONE); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 744 | state = RELEASED; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 745 | } |
| 746 | |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 747 | static uint8_t* alloc_dhcp_option(int code, const char *str, int extra) |
| 748 | { |
| 749 | uint8_t *storage; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 750 | int len = strnlen(str, 255); |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 751 | storage = xzalloc(len + extra + OPT_DATA); |
| 752 | storage[OPT_CODE] = code; |
| 753 | storage[OPT_LEN] = len + extra; |
| 754 | memcpy(storage + extra + OPT_DATA, str, len); |
| 755 | return storage; |
| 756 | } |
| 757 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 758 | #if BB_MMU |
| 759 | static void client_background(void) |
| 760 | { |
| 761 | bb_daemonize(0); |
| 762 | logmode &= ~LOGMODE_STDIO; |
| 763 | /* rewrite pidfile, as our pid is different now */ |
| 764 | write_pidfile(client_config.pidfile); |
| 765 | } |
| 766 | #endif |
| 767 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 768 | int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Denis Vlasenko | a60f84e | 2008-07-05 09:18:54 +0000 | [diff] [blame] | 769 | int udhcpc_main(int argc UNUSED_PARAM, char **argv) |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 770 | { |
| 771 | uint8_t *temp, *message; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 772 | const char *str_c, *str_V, *str_h, *str_F, *str_r; |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 773 | IF_FEATURE_UDHCP_PORT(char *str_P;) |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 774 | llist_t *list_O = NULL; |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 775 | llist_t *list_x = NULL; |
Denis Vlasenko | 68af8e7 | 2007-11-22 21:41:14 +0000 | [diff] [blame] | 776 | int tryagain_timeout = 20; |
| 777 | int discover_timeout = 3; |
| 778 | int discover_retries = 3; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 779 | uint32_t server_addr = server_addr; /* for compiler */ |
| 780 | uint32_t requested_ip = 0; |
Denis Vlasenko | 42b3dea | 2007-07-03 15:47:50 +0000 | [diff] [blame] | 781 | uint32_t xid = 0; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 782 | uint32_t lease_seconds = 0; /* can be given as 32-bit quantity */ |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 783 | int packet_num; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 784 | int timeout; /* must be signed */ |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 785 | unsigned already_waited_sec; |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 786 | unsigned opt; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 787 | int max_fd; |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 788 | int retval; |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 789 | struct timeval tv; |
Denys Vlasenko | 31af3d5 | 2009-06-17 11:57:09 +0200 | [diff] [blame] | 790 | struct dhcp_packet packet; |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 791 | fd_set rfds; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 792 | |
Denys Vlasenko | f3b92d3 | 2009-06-19 12:10:38 +0200 | [diff] [blame] | 793 | #if ENABLE_LONG_OPTS |
Denis Vlasenko | 6ca409e | 2007-08-12 20:58:27 +0000 | [diff] [blame] | 794 | static const char udhcpc_longopts[] ALIGN1 = |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 795 | "clientid\0" Required_argument "c" |
| 796 | "clientid-none\0" No_argument "C" |
| 797 | "vendorclass\0" Required_argument "V" |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 798 | "hostname\0" Required_argument "H" |
| 799 | "fqdn\0" Required_argument "F" |
| 800 | "interface\0" Required_argument "i" |
| 801 | "now\0" No_argument "n" |
| 802 | "pidfile\0" Required_argument "p" |
| 803 | "quit\0" No_argument "q" |
| 804 | "release\0" No_argument "R" |
| 805 | "request\0" Required_argument "r" |
| 806 | "script\0" Required_argument "s" |
| 807 | "timeout\0" Required_argument "T" |
| 808 | "version\0" No_argument "v" |
| 809 | "retries\0" Required_argument "t" |
| 810 | "tryagain\0" Required_argument "A" |
| 811 | "syslog\0" No_argument "S" |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 812 | "request-option\0" Required_argument "O" |
| 813 | "no-default-options\0" No_argument "o" |
| 814 | "foreground\0" No_argument "f" |
| 815 | "background\0" No_argument "b" |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 816 | IF_FEATURE_UDHCPC_ARPING("arping\0" No_argument "a") |
| 817 | IF_FEATURE_UDHCP_PORT("client-port\0" Required_argument "P") |
Denis Vlasenko | 990d0f6 | 2007-07-24 15:54:42 +0000 | [diff] [blame] | 818 | ; |
Denis Vlasenko | c61852a | 2006-11-29 11:09:43 +0000 | [diff] [blame] | 819 | #endif |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 820 | enum { |
| 821 | OPT_c = 1 << 0, |
| 822 | OPT_C = 1 << 1, |
| 823 | OPT_V = 1 << 2, |
| 824 | OPT_H = 1 << 3, |
| 825 | OPT_h = 1 << 4, |
| 826 | OPT_F = 1 << 5, |
Denis Vlasenko | f716a6d | 2008-06-15 09:49:21 +0000 | [diff] [blame] | 827 | OPT_i = 1 << 6, |
| 828 | OPT_n = 1 << 7, |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 829 | OPT_p = 1 << 8, |
| 830 | OPT_q = 1 << 9, |
| 831 | OPT_R = 1 << 10, |
| 832 | OPT_r = 1 << 11, |
| 833 | OPT_s = 1 << 12, |
| 834 | OPT_T = 1 << 13, |
| 835 | OPT_t = 1 << 14, |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 836 | OPT_S = 1 << 15, |
| 837 | OPT_A = 1 << 16, |
| 838 | OPT_O = 1 << 17, |
| 839 | OPT_o = 1 << 18, |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 840 | OPT_x = 1 << 19, |
| 841 | OPT_f = 1 << 20, |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 842 | /* The rest has variable bit positions, need to be clever */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 843 | OPTBIT_f = 20, |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 844 | USE_FOR_MMU( OPTBIT_b,) |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 845 | IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,) |
| 846 | IF_FEATURE_UDHCP_PORT( OPTBIT_P,) |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 847 | USE_FOR_MMU( OPT_b = 1 << OPTBIT_b,) |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 848 | IF_FEATURE_UDHCPC_ARPING(OPT_a = 1 << OPTBIT_a,) |
| 849 | IF_FEATURE_UDHCP_PORT( OPT_P = 1 << OPTBIT_P,) |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 850 | }; |
| 851 | |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 852 | /* Default options. */ |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 853 | IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;) |
| 854 | IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;) |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 855 | client_config.interface = "eth0"; |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 856 | client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 857 | str_V = "udhcp "BB_VER; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 858 | |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 859 | /* Parse command line */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 860 | /* Cc: mutually exclusive; O,x: list; -T,-t,-A take numeric param */ |
| 861 | opt_complementary = "c--C:C--c:O::x::T+:t+:A+" |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 862 | #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1 |
| 863 | ":vv" |
| 864 | #endif |
| 865 | ; |
Denys Vlasenko | f3b92d3 | 2009-06-19 12:10:38 +0200 | [diff] [blame] | 866 | IF_LONG_OPTS(applet_long_options = udhcpc_longopts;) |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 867 | opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:f" |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 868 | USE_FOR_MMU("b") |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 869 | IF_FEATURE_UDHCPC_ARPING("a") |
| 870 | IF_FEATURE_UDHCP_PORT("P:") |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 871 | "v" |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 872 | , &str_c, &str_V, &str_h, &str_h, &str_F |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 873 | , &client_config.interface, &client_config.pidfile, &str_r /* i,p */ |
| 874 | , &client_config.script /* s */ |
| 875 | , &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */ |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 876 | , &list_O |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 877 | , &list_x |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame] | 878 | IF_FEATURE_UDHCP_PORT(, &str_P) |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 879 | #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1 |
| 880 | , &dhcp_verbose |
| 881 | #endif |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 882 | ); |
Denis Vlasenko | 68af8e7 | 2007-11-22 21:41:14 +0000 | [diff] [blame] | 883 | if (opt & (OPT_h|OPT_H)) |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 884 | client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0); |
| 885 | if (opt & OPT_F) { |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 886 | /* FQDN option format: [0x51][len][flags][0][0]<fqdn> */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 887 | client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3); |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 888 | /* Flag bits: 0000NEOS |
| 889 | * S: 1 = Client requests server to update A RR in DNS as well as PTR |
| 890 | * O: 1 = Server indicates to client that DNS has been updated regardless |
| 891 | * E: 1 = Name is in DNS format, i.e. <4>host<6>domain<3>com<0>, |
| 892 | * not "host.domain.com". Format 0 is obsolete. |
| 893 | * N: 1 = Client requests server to not update DNS (S must be 0 then) |
| 894 | * Two [0] bytes which follow are deprecated and must be 0. |
| 895 | */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 896 | client_config.fqdn[OPT_DATA + 0] = 0x1; |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 897 | /*client_config.fqdn[OPT_DATA + 1] = 0; - xzalloc did it */ |
| 898 | /*client_config.fqdn[OPT_DATA + 2] = 0; */ |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 899 | } |
Denis Vlasenko | e2d3ded | 2006-11-27 23:43:28 +0000 | [diff] [blame] | 900 | if (opt & OPT_r) |
| 901 | requested_ip = inet_addr(str_r); |
Denis Vlasenko | d55fe3e | 2008-02-04 13:12:16 +0000 | [diff] [blame] | 902 | #if ENABLE_FEATURE_UDHCP_PORT |
| 903 | if (opt & OPT_P) { |
| 904 | CLIENT_PORT = xatou16(str_P); |
| 905 | SERVER_PORT = CLIENT_PORT - 1; |
| 906 | } |
| 907 | #endif |
Denis Vlasenko | 2e4c3c4 | 2008-04-02 13:04:19 +0000 | [diff] [blame] | 908 | if (opt & OPT_o) |
| 909 | client_config.no_default_options = 1; |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 910 | while (list_O) { |
Denis Vlasenko | 18c9302 | 2008-08-27 22:29:43 +0000 | [diff] [blame] | 911 | char *optstr = llist_pop(&list_O); |
Denys Vlasenko | 9107b63 | 2010-03-27 23:23:41 +0100 | [diff] [blame] | 912 | unsigned n = udhcp_option_idx(optstr); |
Denys Vlasenko | c03602b | 2010-04-04 15:28:49 +0200 | [diff] [blame] | 913 | n = dhcp_optflags[n].code; |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 914 | client_config.opt_mask[n >> 3] |= 1 << (n & 7); |
Denis Vlasenko | 1918368 | 2007-12-10 07:03:38 +0000 | [diff] [blame] | 915 | } |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 916 | while (list_x) { |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 917 | char *optstr = llist_pop(&list_x); |
| 918 | char *colon = strchr(optstr, ':'); |
| 919 | if (colon) |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 920 | *colon = ' '; |
Denys Vlasenko | 9c0ea86 | 2010-04-04 02:12:03 +0200 | [diff] [blame] | 921 | /* now it looks similar to udhcpd's config file line: |
| 922 | * "optname optval", using the common routine: */ |
Denys Vlasenko | 7e6add1 | 2010-03-25 20:32:38 +0100 | [diff] [blame] | 923 | udhcp_str2optset(optstr, &client_config.options); |
| 924 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 925 | |
Denys Vlasenko | 26918dd | 2009-06-16 12:04:23 +0200 | [diff] [blame] | 926 | if (udhcp_read_interface(client_config.interface, |
| 927 | &client_config.ifindex, |
| 928 | NULL, |
| 929 | client_config.client_mac) |
| 930 | ) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 931 | return 1; |
Denys Vlasenko | 26918dd | 2009-06-16 12:04:23 +0200 | [diff] [blame] | 932 | } |
| 933 | |
Denys Vlasenko | 87fa216 | 2010-03-20 18:06:23 +0100 | [diff] [blame] | 934 | if (opt & OPT_c) { |
| 935 | client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0); |
| 936 | } else if (!(opt & OPT_C)) { |
| 937 | /* not set and not suppressed, set the default client ID */ |
| 938 | client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7); |
| 939 | client_config.clientid[OPT_DATA] = 1; /* type: ethernet */ |
| 940 | memcpy(client_config.clientid + OPT_DATA+1, client_config.client_mac, 6); |
| 941 | } |
| 942 | if (str_V[0] != '\0') |
| 943 | client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 944 | #if !BB_MMU |
| 945 | /* on NOMMU reexec (i.e., background) early */ |
| 946 | if (!(opt & OPT_f)) { |
| 947 | bb_daemonize_or_rexec(0 /* flags */, argv); |
Denis Vlasenko | a19e649 | 2009-03-11 14:40:00 +0000 | [diff] [blame] | 948 | logmode = LOGMODE_NONE; |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 949 | } |
| 950 | #endif |
| 951 | if (opt & OPT_S) { |
Denis Vlasenko | 5e4fda0 | 2009-03-08 23:46:48 +0000 | [diff] [blame] | 952 | openlog(applet_name, LOG_PID, LOG_DAEMON); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 953 | logmode |= LOGMODE_SYSLOG; |
| 954 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 955 | |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 956 | /* Make sure fd 0,1,2 are open */ |
| 957 | bb_sanitize_stdio(); |
| 958 | /* Equivalent of doing a fflush after every \n */ |
| 959 | setlinebuf(stdout); |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 960 | /* Create pidfile */ |
| 961 | write_pidfile(client_config.pidfile); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 962 | /* Goes to stdout (unless NOMMU) and possibly syslog */ |
Denis Vlasenko | def8898 | 2007-10-07 17:06:01 +0000 | [diff] [blame] | 963 | bb_info_msg("%s (v"BB_VER") started", applet_name); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 964 | /* Set up the signal pipe */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 965 | udhcp_sp_setup(); |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 966 | /* We want random_xid to be random... */ |
| 967 | srand(monotonic_us()); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 968 | |
| 969 | state = INIT_SELECTING; |
Rob Landley | 3f78561 | 2006-05-28 01:06:36 +0000 | [diff] [blame] | 970 | udhcp_run_script(NULL, "deconfig"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 971 | change_listen_mode(LISTEN_RAW); |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 972 | packet_num = 0; |
Denis Vlasenko | fc9e108 | 2008-05-26 17:32:35 +0000 | [diff] [blame] | 973 | timeout = 0; |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 974 | already_waited_sec = 0; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 975 | |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 976 | /* Main event loop. select() waits on signal pipe and possibly |
| 977 | * on sockfd. |
| 978 | * "continue" statements in code below jump to the top of the loop. |
| 979 | */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 980 | for (;;) { |
Denis Vlasenko | ec64a57 | 2009-01-14 00:28:03 +0000 | [diff] [blame] | 981 | /* silence "uninitialized!" warning */ |
| 982 | unsigned timestamp_before_wait = timestamp_before_wait; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 983 | |
Denis Vlasenko | 517413f | 2008-12-10 11:16:47 +0000 | [diff] [blame] | 984 | //bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode); |
| 985 | |
| 986 | /* Was opening raw or udp socket here |
| 987 | * if (listen_mode != LISTEN_NONE && sockfd < 0), |
| 988 | * but on fast network renew responses return faster |
| 989 | * than we open sockets. Thus this code is moved |
| 990 | * to change_listen_mode(). Thus we open listen socket |
| 991 | * BEFORE we send renew request (see "case BOUND:"). */ |
| 992 | |
Denis Vlasenko | fbd2918 | 2007-04-07 01:05:47 +0000 | [diff] [blame] | 993 | max_fd = udhcp_sp_fd_set(&rfds, sockfd); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 994 | |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 995 | tv.tv_sec = timeout - already_waited_sec; |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 996 | tv.tv_usec = 0; |
Denys Vlasenko | 8d11445 | 2010-03-22 13:44:09 +0100 | [diff] [blame] | 997 | retval = 0; |
| 998 | /* If we already timed out, fall through with retval = 0, else... */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 999 | if ((int)tv.tv_sec > 0) { |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1000 | timestamp_before_wait = (unsigned)monotonic_sec(); |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1001 | log1("Waiting on select..."); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1002 | retval = select(max_fd + 1, &rfds, NULL, NULL, &tv); |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1003 | if (retval < 0) { |
| 1004 | /* EINTR? A signal was caught, don't panic */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1005 | if (errno == EINTR) { |
| 1006 | already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait; |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1007 | continue; |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1008 | } |
Denis Vlasenko | 80edead | 2007-08-02 22:31:05 +0000 | [diff] [blame] | 1009 | /* Else: an error occured, panic! */ |
| 1010 | bb_perror_msg_and_die("select"); |
| 1011 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1012 | } |
| 1013 | |
| 1014 | /* If timeout dropped to zero, time to become active: |
| 1015 | * resend discover/renew/whatever |
| 1016 | */ |
| 1017 | if (retval == 0) { |
Denis Vlasenko | f1980f6 | 2008-09-26 09:34:59 +0000 | [diff] [blame] | 1018 | /* We will restart the wait in any case */ |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1019 | already_waited_sec = 0; |
| 1020 | |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1021 | switch (state) { |
| 1022 | case INIT_SELECTING: |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1023 | if (packet_num < discover_retries) { |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1024 | if (packet_num == 0) |
| 1025 | xid = random_xid(); |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1026 | /* broadcast */ |
| 1027 | send_discover(xid, requested_ip); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1028 | timeout = discover_timeout; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1029 | packet_num++; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1030 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1031 | } |
Denis Vlasenko | cdb0b65 | 2008-09-26 09:34:15 +0000 | [diff] [blame] | 1032 | leasefail: |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1033 | udhcp_run_script(NULL, "leasefail"); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1034 | #if BB_MMU /* -b is not supported on NOMMU */ |
| 1035 | if (opt & OPT_b) { /* background if no lease */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1036 | bb_info_msg("No lease, forking to background"); |
| 1037 | client_background(); |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1038 | /* do not background again! */ |
| 1039 | opt = ((opt & ~OPT_b) | OPT_f); |
| 1040 | } else |
| 1041 | #endif |
| 1042 | if (opt & OPT_n) { /* abort if no lease */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1043 | bb_info_msg("No lease, failing"); |
| 1044 | retval = 1; |
| 1045 | goto ret; |
| 1046 | } |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1047 | /* wait before trying again */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1048 | timeout = tryagain_timeout; |
| 1049 | packet_num = 0; |
| 1050 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1051 | case REQUESTING: |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1052 | if (packet_num < discover_retries) { |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1053 | /* send broadcast select packet */ |
| 1054 | send_select(xid, server_addr, requested_ip); |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1055 | timeout = discover_timeout; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1056 | packet_num++; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1057 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1058 | } |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1059 | /* Timed out, go back to init state. |
| 1060 | * "discover...select...discover..." loops |
Denis Vlasenko | 7d9399e | 2008-09-26 22:21:03 +0000 | [diff] [blame] | 1061 | * were seen in the wild. Treat them similarly |
Denis Vlasenko | cdb0b65 | 2008-09-26 09:34:15 +0000 | [diff] [blame] | 1062 | * to "no response to discover" case */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1063 | change_listen_mode(LISTEN_RAW); |
Denis Vlasenko | 7d9399e | 2008-09-26 22:21:03 +0000 | [diff] [blame] | 1064 | state = INIT_SELECTING; |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1065 | goto leasefail; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1066 | case BOUND: |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1067 | /* 1/2 lease passed, enter renewing state */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1068 | state = RENEWING; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1069 | change_listen_mode(LISTEN_KERNEL); |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1070 | log1("Entering renew state"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1071 | /* fall right through */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1072 | case RENEW_REQUESTED: /* manual (SIGUSR1) renew */ |
| 1073 | case_RENEW_REQUESTED: |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1074 | case RENEWING: |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1075 | if (timeout > 60) { |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1076 | /* send an unicast renew request */ |
| 1077 | /* Sometimes observed to fail (EADDRNOTAVAIL) to bind |
| 1078 | * a new UDP socket for sending inside send_renew. |
| 1079 | * I hazard to guess existing listening socket |
| 1080 | * is somehow conflicting with it, but why is it |
| 1081 | * not deterministic then?! Strange. |
Denys Vlasenko | 753a3ce | 2009-07-19 04:27:10 +0200 | [diff] [blame] | 1082 | * Anyway, it does recover by eventually failing through |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1083 | * into INIT_SELECTING state. |
| 1084 | */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1085 | send_renew(xid, server_addr, requested_ip); |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1086 | timeout >>= 1; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1087 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1088 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1089 | /* Timed out, enter rebinding state */ |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1090 | log1("Entering rebinding state"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1091 | state = REBINDING; |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1092 | /* fall right through */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1093 | case REBINDING: |
Denys Vlasenko | 219757f | 2009-10-08 23:05:46 +0200 | [diff] [blame] | 1094 | /* Switch to bcast receive */ |
| 1095 | change_listen_mode(LISTEN_RAW); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1096 | /* Lease is *really* about to run out, |
| 1097 | * try to find DHCP server using broadcast */ |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1098 | if (timeout > 0) { |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1099 | /* send a broadcast renew request */ |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1100 | send_renew(xid, 0 /*INADDR_ANY*/, requested_ip); |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1101 | timeout >>= 1; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1102 | continue; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1103 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1104 | /* Timed out, enter init state */ |
| 1105 | bb_info_msg("Lease lost, entering init state"); |
| 1106 | udhcp_run_script(NULL, "deconfig"); |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1107 | state = INIT_SELECTING; |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1108 | /*timeout = 0; - already is */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1109 | packet_num = 0; |
| 1110 | continue; |
| 1111 | /* case RELEASED: */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1112 | } |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1113 | /* yah, I know, *you* say it would never happen */ |
| 1114 | timeout = INT_MAX; |
| 1115 | continue; /* back to main loop */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1116 | } /* if select timed out */ |
| 1117 | |
| 1118 | /* select() didn't timeout, something happened */ |
| 1119 | |
| 1120 | /* Is it a signal? */ |
| 1121 | /* note: udhcp_sp_read checks FD_ISSET before reading */ |
| 1122 | switch (udhcp_sp_read(&rfds)) { |
| 1123 | case SIGUSR1: |
| 1124 | perform_renew(); |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1125 | if (state == RENEW_REQUESTED) |
| 1126 | goto case_RENEW_REQUESTED; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1127 | /* Start things over */ |
| 1128 | packet_num = 0; |
Denys Vlasenko | 7d6a791 | 2009-07-19 04:24:23 +0200 | [diff] [blame] | 1129 | /* Kill any timeouts, user wants this to hurry along */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1130 | timeout = 0; |
| 1131 | continue; |
| 1132 | case SIGUSR2: |
| 1133 | perform_release(requested_ip, server_addr); |
| 1134 | timeout = INT_MAX; |
| 1135 | continue; |
| 1136 | case SIGTERM: |
| 1137 | bb_info_msg("Received SIGTERM"); |
| 1138 | if (opt & OPT_R) /* release on quit */ |
| 1139 | perform_release(requested_ip, server_addr); |
| 1140 | goto ret0; |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1141 | } |
| 1142 | |
Denis Vlasenko | 739e30f | 2008-09-26 23:45:20 +0000 | [diff] [blame] | 1143 | /* Is it a packet? */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1144 | if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds)) |
| 1145 | continue; /* no */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1146 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1147 | { |
| 1148 | int len; |
| 1149 | |
| 1150 | /* A packet is ready, read it */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1151 | if (listen_mode == LISTEN_KERNEL) |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1152 | len = udhcp_recv_kernel_packet(&packet, sockfd); |
Denis Vlasenko | b76b9a4 | 2008-01-25 22:46:34 +0000 | [diff] [blame] | 1153 | else |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1154 | len = udhcp_recv_raw_packet(&packet, sockfd); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1155 | if (len == -1) { |
| 1156 | /* Error is severe, reopen socket */ |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1157 | bb_info_msg("Read error: %s, reopening socket", strerror(errno)); |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1158 | sleep(discover_timeout); /* 3 seconds by default */ |
| 1159 | change_listen_mode(listen_mode); /* just close and reopen */ |
| 1160 | } |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1161 | /* If this packet will turn out to be unrelated/bogus, |
| 1162 | * we will go back and wait for next one. |
| 1163 | * Be sure timeout is properly decreased. */ |
Denis Vlasenko | 19903f0 | 2008-05-21 07:03:03 +0000 | [diff] [blame] | 1164 | already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait; |
Denis Vlasenko | 6de8994 | 2008-05-21 07:05:06 +0000 | [diff] [blame] | 1165 | if (len < 0) |
| 1166 | continue; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1167 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1168 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1169 | if (packet.xid != xid) { |
| 1170 | log1("xid %x (our is %x), ignoring packet", |
| 1171 | (unsigned)packet.xid, (unsigned)xid); |
| 1172 | continue; |
| 1173 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1174 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1175 | /* Ignore packets that aren't for us */ |
| 1176 | if (packet.hlen != 6 |
| 1177 | || memcmp(packet.chaddr, client_config.client_mac, 6) |
| 1178 | ) { |
Denys Vlasenko | ac906fa | 2009-06-17 11:54:52 +0200 | [diff] [blame] | 1179 | //FIXME: need to also check that last 10 bytes are zero |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1180 | log1("chaddr does not match, ignoring packet"); // log2? |
| 1181 | continue; |
| 1182 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1183 | |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1184 | message = udhcp_get_option(&packet, DHCP_MESSAGE_TYPE); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1185 | if (message == NULL) { |
| 1186 | bb_error_msg("no message type option, ignoring packet"); |
| 1187 | continue; |
| 1188 | } |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1189 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1190 | switch (state) { |
| 1191 | case INIT_SELECTING: |
| 1192 | /* Must be a DHCPOFFER to one of our xid's */ |
| 1193 | if (*message == DHCPOFFER) { |
| 1194 | /* TODO: why we don't just fetch server's IP from IP header? */ |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1195 | temp = udhcp_get_option(&packet, DHCP_SERVER_ID); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1196 | if (!temp) { |
| 1197 | bb_error_msg("no server ID in message"); |
| 1198 | continue; |
| 1199 | /* still selecting - this server looks bad */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1200 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1201 | /* it IS unaligned sometimes, don't "optimize" */ |
| 1202 | move_from_unaligned32(server_addr, temp); |
| 1203 | xid = packet.xid; |
| 1204 | requested_ip = packet.yiaddr; |
| 1205 | |
| 1206 | /* enter requesting state */ |
| 1207 | state = REQUESTING; |
| 1208 | timeout = 0; |
| 1209 | packet_num = 0; |
| 1210 | already_waited_sec = 0; |
| 1211 | } |
| 1212 | continue; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1213 | case REQUESTING: |
| 1214 | case RENEWING: |
Denys Vlasenko | 13ca4b1 | 2009-07-19 04:07:21 +0200 | [diff] [blame] | 1215 | case RENEW_REQUESTED: |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1216 | case REBINDING: |
| 1217 | if (*message == DHCPACK) { |
Denys Vlasenko | dde8bdc | 2010-03-22 14:29:13 +0100 | [diff] [blame] | 1218 | temp = udhcp_get_option(&packet, DHCP_LEASE_TIME); |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1219 | if (!temp) { |
| 1220 | bb_error_msg("no lease time with ACK, using 1 hour lease"); |
| 1221 | lease_seconds = 60 * 60; |
| 1222 | } else { |
| 1223 | /* it IS unaligned sometimes, don't "optimize" */ |
| 1224 | move_from_unaligned32(lease_seconds, temp); |
| 1225 | lease_seconds = ntohl(lease_seconds); |
| 1226 | lease_seconds &= 0x0fffffff; /* paranoia: must not be prone to overflows */ |
| 1227 | if (lease_seconds < 10) /* and not too small */ |
| 1228 | lease_seconds = 10; |
| 1229 | } |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1230 | #if ENABLE_FEATURE_UDHCPC_ARPING |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1231 | if (opt & OPT_a) { |
Denis Vlasenko | 739e30f | 2008-09-26 23:45:20 +0000 | [diff] [blame] | 1232 | /* RFC 2131 3.1 paragraph 5: |
| 1233 | * "The client receives the DHCPACK message with configuration |
| 1234 | * parameters. The client SHOULD perform a final check on the |
| 1235 | * parameters (e.g., ARP for allocated network address), and notes |
| 1236 | * the duration of the lease specified in the DHCPACK message. At this |
| 1237 | * point, the client is configured. If the client detects that the |
| 1238 | * address is already in use (e.g., through the use of ARP), |
| 1239 | * the client MUST send a DHCPDECLINE message to the server and restarts |
| 1240 | * the configuration process..." */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1241 | if (!arpping(packet.yiaddr, |
| 1242 | NULL, |
| 1243 | (uint32_t) 0, |
| 1244 | client_config.client_mac, |
| 1245 | client_config.interface) |
| 1246 | ) { |
| 1247 | bb_info_msg("Offered address is in use " |
| 1248 | "(got ARP reply), declining"); |
| 1249 | send_decline(xid, server_addr, packet.yiaddr); |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1250 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1251 | if (state != REQUESTING) |
| 1252 | udhcp_run_script(NULL, "deconfig"); |
| 1253 | change_listen_mode(LISTEN_RAW); |
| 1254 | state = INIT_SELECTING; |
| 1255 | requested_ip = 0; |
| 1256 | timeout = tryagain_timeout; |
| 1257 | packet_num = 0; |
| 1258 | already_waited_sec = 0; |
| 1259 | continue; /* back to main loop */ |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1260 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1261 | } |
Denis Vlasenko | 223bc97 | 2007-11-22 00:58:49 +0000 | [diff] [blame] | 1262 | #endif |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1263 | /* enter bound state */ |
| 1264 | timeout = lease_seconds / 2; |
| 1265 | { |
| 1266 | struct in_addr temp_addr; |
| 1267 | temp_addr.s_addr = packet.yiaddr; |
| 1268 | bb_info_msg("Lease of %s obtained, lease time %u", |
| 1269 | inet_ntoa(temp_addr), (unsigned)lease_seconds); |
| 1270 | } |
| 1271 | requested_ip = packet.yiaddr; |
Denys Vlasenko | 4abfc26 | 2009-07-19 04:35:16 +0200 | [diff] [blame] | 1272 | udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew"); |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1273 | |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1274 | state = BOUND; |
| 1275 | change_listen_mode(LISTEN_NONE); |
| 1276 | if (opt & OPT_q) { /* quit after lease */ |
| 1277 | if (opt & OPT_R) /* release on quit */ |
| 1278 | perform_release(requested_ip, server_addr); |
| 1279 | goto ret0; |
| 1280 | } |
Justin Maggard | aa369e0 | 2009-08-13 01:26:17 +0200 | [diff] [blame] | 1281 | /* future renew failures should not exit (JM) */ |
| 1282 | opt &= ~OPT_n; |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1283 | #if BB_MMU /* NOMMU case backgrounded earlier */ |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1284 | if (!(opt & OPT_f)) { |
| 1285 | client_background(); |
| 1286 | /* do not background again! */ |
| 1287 | opt = ((opt & ~OPT_b) | OPT_f); |
| 1288 | } |
Denis Vlasenko | 21765fa | 2008-06-13 20:44:05 +0000 | [diff] [blame] | 1289 | #endif |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1290 | already_waited_sec = 0; |
| 1291 | continue; /* back to main loop */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1292 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1293 | if (*message == DHCPNAK) { |
| 1294 | /* return to init state */ |
| 1295 | bb_info_msg("Received DHCP NAK"); |
| 1296 | udhcp_run_script(&packet, "nak"); |
| 1297 | if (state != REQUESTING) |
| 1298 | udhcp_run_script(NULL, "deconfig"); |
| 1299 | change_listen_mode(LISTEN_RAW); |
| 1300 | sleep(3); /* avoid excessive network traffic */ |
| 1301 | state = INIT_SELECTING; |
| 1302 | requested_ip = 0; |
Denis Vlasenko | b539c84 | 2007-11-29 08:17:45 +0000 | [diff] [blame] | 1303 | timeout = 0; |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1304 | packet_num = 0; |
| 1305 | already_waited_sec = 0; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1306 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1307 | continue; |
| 1308 | /* case BOUND: - ignore all packets */ |
| 1309 | /* case RELEASED: - ignore all packets */ |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1310 | } |
Denys Vlasenko | 4248c33 | 2009-06-26 23:23:16 +0200 | [diff] [blame] | 1311 | /* back to main loop */ |
Denis Vlasenko | 9cdfd14 | 2007-11-22 01:00:00 +0000 | [diff] [blame] | 1312 | } /* for (;;) - main loop ends */ |
| 1313 | |
Denis Vlasenko | 6e6d331 | 2007-05-03 23:39:35 +0000 | [diff] [blame] | 1314 | ret0: |
| 1315 | retval = 0; |
| 1316 | ret: |
Denis Vlasenko | b234291 | 2008-05-21 07:02:16 +0000 | [diff] [blame] | 1317 | /*if (client_config.pidfile) - remove_pidfile has its own check */ |
Denis Vlasenko | 6e6d331 | 2007-05-03 23:39:35 +0000 | [diff] [blame] | 1318 | remove_pidfile(client_config.pidfile); |
| 1319 | return retval; |
Mike Frysinger | 7031f62 | 2006-05-08 03:20:50 +0000 | [diff] [blame] | 1320 | } |