| /* vi: set sw=4 ts=4: */ |
| /* |
| * Russ Dill <Russ.Dill@asu.edu> September 2001 |
| * Rewritten by Vladimir Oleynik <dzo@simtreas.ru> (C) 2003 |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| #ifndef UDHCP_COMMON_H |
| #define UDHCP_COMMON_H 1 |
| |
| #include "libbb.h" |
| #include "common_bufsiz.h" |
| #include <netinet/udp.h> |
| #include <netinet/ip.h> |
| |
| PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN |
| |
| extern const uint8_t MAC_BCAST_ADDR[6] ALIGN2; /* six all-ones */ |
| |
| |
| /*** DHCP packet ***/ |
| |
| /* DHCP protocol. See RFC 2131 */ |
| #define DHCP_MAGIC 0x63825363 |
| #define DHCP_OPTIONS_BUFSIZE 308 |
| #define BOOTREQUEST 1 |
| #define BOOTREPLY 2 |
| |
| //TODO: rename ciaddr/yiaddr/chaddr |
| struct dhcp_packet { |
| uint8_t op; /* BOOTREQUEST or BOOTREPLY */ |
| uint8_t htype; /* hardware address type. 1 = 10mb ethernet */ |
| uint8_t hlen; /* hardware address length */ |
| uint8_t hops; /* used by relay agents only */ |
| uint32_t xid; /* unique id */ |
| uint16_t secs; /* elapsed since client began acquisition/renewal */ |
| uint16_t flags; /* only one flag so far: */ |
| #define BROADCAST_FLAG 0x8000 /* "I need broadcast replies" */ |
| uint32_t ciaddr; /* client IP (if client is in BOUND, RENEW or REBINDING state) */ |
| uint32_t yiaddr; /* 'your' (client) IP address */ |
| /* IP address of "next server" (usually meant to be an TFTP server) |
| * to use in bootstrap, returned in DHCPOFFER, DHCPACK by server: */ |
| uint32_t siaddr_nip; |
| /* RFC 951 (BOOTP): "place my (server) IP address in the 'siaddr' field" |
| * (IOW: unconditionally, not just if we are also a TFTP server). |
| * DHCP servers don't have to do this, they add SERVER_ID option |
| * to their reply packets to let client identify lease-giving server. |
| */ |
| uint32_t gateway_nip; /* aka 'giaddr': relay agent IP address, else 0 */ |
| uint8_t chaddr[16]; /* link-layer client hardware address (MAC) */ |
| uint8_t sname[64]; /* server host name (ASCIZ) */ |
| /* RFC 951 (BOOTP): "If the client wishes to restrict booting |
| * to a particular server name, it may place [it] in 'sname'" |
| */ |
| uint8_t file[128]; /* boot file name (ASCIZ) */ |
| /* RFC 951 (BOOTP): in client requests, "...can be a 'generic' name |
| * such as 'unix' or 'gateway'; this means 'boot the named program |
| * configured for my machine'" |
| */ |
| /* BOOTP fields end here, BOOTP says optional uint8_t vend[64] follows */ |
| uint32_t cookie; /* DHCP magic bytes: 99,130,83,99 decimal */ |
| uint8_t options[DHCP_OPTIONS_BUFSIZE + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS]; |
| }; |
| #define DHCP_PKT_SNAME_LEN 64 |
| #define DHCP_PKT_FILE_LEN 128 |
| #define DHCP_PKT_SNAME_LEN_STR "64" |
| #define DHCP_PKT_FILE_LEN_STR "128" |
| |
| struct ip_udp_dhcp_packet { |
| struct iphdr ip; |
| struct udphdr udp; |
| struct dhcp_packet data; |
| }; |
| |
| struct udp_dhcp_packet { |
| struct udphdr udp; |
| struct dhcp_packet data; |
| }; |
| |
| enum { |
| IP_UDP_DHCP_SIZE = sizeof(struct ip_udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS, |
| UDP_DHCP_SIZE = sizeof(struct udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS, |
| DHCP_SIZE = sizeof(struct dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS, |
| }; |
| |
| /* Let's see whether compiler understood us right */ |
| struct BUG_bad_sizeof_struct_ip_udp_dhcp_packet { |
| char c[IP_UDP_DHCP_SIZE == 576 ? 1 : -1]; |
| }; |
| |
| |
| /*** Options ***/ |
| |
| enum { |
| OPTION_IP = 0, |
| OPTION_IP_PAIR, |
| OPTION_STRING, |
| /* Opts of STRING_HOST type will be sanitized before they are passed |
| * to udhcpc script's environment: */ |
| OPTION_STRING_HOST, |
| // OPTION_BOOLEAN, |
| OPTION_U8, |
| OPTION_U16, |
| // OPTION_S16, |
| OPTION_U32, |
| OPTION_S32, |
| OPTION_BIN, |
| OPTION_STATIC_ROUTES, |
| OPTION_6RD, |
| #if ENABLE_FEATURE_UDHCP_RFC3397 || ENABLE_FEATURE_UDHCPC6_RFC3646 || ENABLE_FEATURE_UDHCPC6_RFC4704 |
| OPTION_DNS_STRING, /* RFC1035 compressed domain name list */ |
| #endif |
| #if ENABLE_FEATURE_UDHCP_RFC3397 |
| OPTION_SIP_SERVERS, |
| #endif |
| |
| OPTION_TYPE_MASK = 0x0f, |
| /* Client requests this option by default */ |
| OPTION_REQ = 0x10, |
| /* There can be a list of 1 or more of these */ |
| OPTION_LIST = 0x20, |
| }; |
| |
| struct dhcp_scan_state { |
| int overload; |
| int rem; |
| uint8_t *optionptr; |
| }; |
| |
| /* DHCP option codes (partial list). See RFC 2132 and |
| * http://www.iana.org/assignments/bootp-dhcp-parameters/ |
| * Commented out options are handled by common option machinery, |
| * uncommented ones have special cases (grep for them to see). |
| */ |
| #define DHCP_PADDING 0x00 |
| #define DHCP_SUBNET 0x01 |
| //#define DHCP_TIME_OFFSET 0x02 /* (localtime - UTC_time) in seconds. signed */ |
| //#define DHCP_ROUTER 0x03 |
| //#define DHCP_TIME_SERVER 0x04 /* RFC 868 time server (32-bit, 0 = 1.1.1900) */ |
| //#define DHCP_NAME_SERVER 0x05 /* IEN 116 _really_ ancient kind of NS */ |
| //#define DHCP_DNS_SERVER 0x06 |
| //#define DHCP_LOG_SERVER 0x07 /* port 704 UDP log (not syslog) */ |
| //#define DHCP_COOKIE_SERVER 0x08 /* "quote of the day" server */ |
| //#define DHCP_LPR_SERVER 0x09 |
| #define DHCP_HOST_NAME 0x0c /* 12: either client informs server or server gives name to client */ |
| //#define DHCP_BOOT_SIZE 0x0d |
| //#define DHCP_DOMAIN_NAME 0x0f /* 15: server gives domain suffix */ |
| //#define DHCP_SWAP_SERVER 0x10 |
| //#define DHCP_ROOT_PATH 0x11 |
| //#define DHCP_IP_TTL 0x17 |
| //#define DHCP_MTU 0x1a |
| //#define DHCP_BROADCAST 0x1c |
| //#define DHCP_ROUTES 0x21 |
| //#define DHCP_NIS_DOMAIN 0x28 |
| //#define DHCP_NIS_SERVER 0x29 |
| //#define DHCP_NTP_SERVER 0x2a |
| //#define DHCP_WINS_SERVER 0x2c |
| #define DHCP_REQUESTED_IP 0x32 /* 50: sent by client if specific IP is wanted */ |
| #define DHCP_LEASE_TIME 0x33 /* 51: 32bit big-endian */ |
| #define DHCP_OPTION_OVERLOAD 0x34 /* 52: 1 byte */ |
| #define DHCP_MESSAGE_TYPE 0x35 /* 53: 1 byte */ |
| #define DHCP_SERVER_ID 0x36 /* 54: server's IP */ |
| #define DHCP_PARAM_REQ 0x37 /* 55: list of options client wants */ |
| //#define DHCP_ERR_MESSAGE 0x38 /* 56: error message when sending NAK etc */ |
| #define DHCP_MAX_SIZE 0x39 /* 57: 16bit big-endian */ |
| // 0x3a /* 58: from server: renew time, 32bit big-endian */ |
| // 0x3b /* 59: from server: rebind time, 32bit big-endian */ |
| #define DHCP_VENDOR 0x3c /* 60: client's vendor (a string) */ |
| #define DHCP_CLIENT_ID 0x3d /* 61: by default client's MAC addr, but may be arbitrarily long */ |
| //#define DHCP_TFTP_SERVER_NAME 0x42 /* 66: same as 'sname' field */ |
| //#define DHCP_BOOT_FILE 0x43 /* 67: same as 'file' field */ |
| //#define DHCP_USER_CLASS 0x4d /* 77: RFC 3004. set of LASCII strings. "I am a printer" etc */ |
| // 0x50 /* 80: rapid commit ("I'm ok with getting immediate ACK, not just OFFER"), 0 bytes */ |
| #define DHCP_FQDN 0x51 /* 81: client asks to update DNS to map its FQDN to its new IP */ |
| //#define DHCP_PCODE 0x64 /* 100: RFC 4833. IEEE 1003.1 TZ string */ |
| //#define DHCP_TCODE 0x65 /* 101: RFC 4833. Reference to the TZ database string */ |
| //#define DHCP_DOMAIN_SEARCH 0x77 /* 119: RFC 3397. set of ASCIZ string, DNS-style compressed */ |
| //#define DHCP_SIP_SERVERS 0x78 /* 120: RFC 3361. flag byte, then: 0: domain names, 1: IP addrs */ |
| //#define DHCP_STATIC_ROUTES 0x79 /* 121: RFC 3442. (mask,ip,router) tuples */ |
| //#define DHCP_VLAN_ID 0x84 /* 132: 802.1P VLAN ID */ |
| //#define DHCP_VLAN_PRIORITY 0x85 /* 133: 802.1Q VLAN priority */ |
| //#define DHCP_PXE_CONF_FILE 0xd1 /* 209: RFC 5071 Configuration file */ |
| //#define DHCP_PXE_PATH_PREFIX 0xd2 /* 210: RFC 5071 Path prefix */ |
| //#define DHCP_REBOOT_TIME 0xd3 /* 211: RFC 5071 Reboot time */ |
| //#define DHCP_MS_STATIC_ROUTES 0xf9 /* 249: Microsoft's pre-RFC 3442 code for 0x79? */ |
| //#define DHCP_WPAD 0xfc /* 252: MSIE's Web Proxy Autodiscovery Protocol */ |
| #define DHCP_END 0xff /* 255: */ |
| |
| /* Offsets in option byte sequence */ |
| #define OPT_CODE 0 |
| #define OPT_LEN 1 |
| #define OPT_DATA 2 |
| /* Offsets in option byte sequence for DHCPv6 */ |
| #define D6_OPT_CODE 0 |
| #define D6_OPT_LEN 2 |
| #define D6_OPT_DATA 4 |
| /* Bits in "overload" option */ |
| #define OPTION_FIELD 0 |
| #define FILE_FIELD 1 |
| #define SNAME_FIELD 2 |
| |
| /* DHCP_MESSAGE_TYPE values */ |
| #define DHCPDISCOVER 1 /* client -> server */ |
| #define DHCPOFFER 2 /* client <- server */ |
| #define DHCPREQUEST 3 /* client -> server */ |
| #define DHCPDECLINE 4 /* client -> server */ |
| #define DHCPACK 5 /* client <- server */ |
| #define DHCPNAK 6 /* client <- server */ |
| #define DHCPRELEASE 7 /* client -> server */ |
| #define DHCPINFORM 8 /* client -> server */ |
| #define DHCP_MINTYPE DHCPDISCOVER |
| #define DHCP_MAXTYPE DHCPINFORM |
| |
| struct dhcp_optflag { |
| uint8_t flags; |
| uint8_t code; |
| }; |
| |
| struct option_set { |
| uint8_t *data; |
| struct option_set *next; |
| }; |
| |
| #if ENABLE_UDHCPC || ENABLE_UDHCPD |
| extern const struct dhcp_optflag dhcp_optflags[]; |
| extern const char dhcp_option_strings[] ALIGN1; |
| #endif |
| extern const uint8_t dhcp_option_lengths[] ALIGN1; |
| |
| unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings); |
| |
| void init_scan_state(struct dhcp_packet *packet, struct dhcp_scan_state *scan_state) FAST_FUNC; |
| uint8_t *udhcp_scan_options(struct dhcp_packet *packet, struct dhcp_scan_state *scan_state) FAST_FUNC; |
| uint8_t *udhcp_get_option(struct dhcp_packet *packet, int code) FAST_FUNC; |
| /* Same as above + ensures that option length is 4 bytes |
| * (returns NULL if size is different) |
| */ |
| uint8_t *udhcp_get_option32(struct dhcp_packet *packet, int code) FAST_FUNC; |
| int udhcp_end_option(uint8_t *optionptr) FAST_FUNC; |
| void udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt) FAST_FUNC; |
| #if ENABLE_UDHCPC || ENABLE_UDHCPD |
| void udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data) FAST_FUNC; |
| #endif |
| #if ENABLE_FEATURE_UDHCP_RFC3397 || ENABLE_FEATURE_UDHCPC6_RFC3646 || ENABLE_FEATURE_UDHCPC6_RFC4704 |
| char *dname_dec(const uint8_t *cstr, int clen, const char *pre) FAST_FUNC; |
| uint8_t *dname_enc(/*const uint8_t *cstr, int clen,*/ const char *src, int *retlen) FAST_FUNC; |
| #endif |
| #if !ENABLE_UDHCPC6 |
| #define udhcp_find_option(opt_list, code, dhcpv6) \ |
| udhcp_find_option(opt_list, code) |
| #endif |
| struct option_set *udhcp_find_option(struct option_set *opt_list, uint8_t code, bool dhcpv6) FAST_FUNC; |
| |
| // RFC 2131 Table 5: Fields and options used by DHCP clients |
| // |
| // Fields 'hops', 'yiaddr', 'siaddr', 'giaddr' are always zero, 'chaddr' is always client's MAC |
| // |
| // Field DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE |
| // ----- ------------ ------------ ----------- ----------- ----------- |
| // 'xid' selected by client selected by client 'xid' from server selected by client selected by client |
| // DHCPOFFER message |
| // 'secs' 0 or seconds since 0 or seconds since 0 or seconds since 0 0 |
| // DHCP process started DHCP process started DHCP process started |
| // 'flags' Set 'BROADCAST' Set 'BROADCAST' Set 'BROADCAST' 0 0 |
| // flag if client needs flag if client needs flag if client needs |
| // broadcast reply broadcast reply broadcast reply |
| // 'ciaddr' 0 client's IP 0 or client's IP 0 client's IP |
| // (BOUND/RENEW/REBIND) |
| // 'sname' options or sname options or sname options or sname (unused) (unused) |
| // 'file' options or file options or file options or file (unused) (unused) |
| // 'options' options options options message type opt message type opt |
| // |
| // Option DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE |
| // ------ ------------ ---------- ----------- ----------- ----------- |
| // Requested IP address MAY MUST NOT MUST (in SELECTING MUST MUST NOT |
| // or INIT-REBOOT) |
| // MUST NOT (in BOUND |
| // or RENEWING) |
| // IP address lease time MAY MUST NOT MAY MUST NOT MUST NOT |
| // Use 'file'/'sname' fields MAY MAY MAY MAY MAY |
| // Client identifier MAY MAY MAY MAY MAY |
| // Vendor class identifier MAY MAY MAY MUST NOT MUST NOT |
| // Server identifier MUST NOT MUST NOT MUST (after SELECTING) MUST MUST |
| // MUST NOT (after |
| // INIT-REBOOT, BOUND, |
| // RENEWING or REBINDING) |
| // Parameter request list MAY MAY MAY MUST NOT MUST NOT |
| // Maximum message size MAY MAY MAY MUST NOT MUST NOT |
| // Message SHOULD NOT SHOULD NOT SHOULD NOT SHOULD SHOULD |
| // Site-specific MAY MAY MAY MUST NOT MUST NOT |
| // All others MAY MAY MAY MUST NOT MUST NOT |
| |
| /*** Logging ***/ |
| |
| #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1 |
| # define IF_UDHCP_VERBOSE(...) __VA_ARGS__ |
| extern unsigned dhcp_verbose; |
| # define log1(...) do { if (dhcp_verbose >= 1) bb_info_msg(__VA_ARGS__); } while (0) |
| //# define log1s(msg) do { if (dhcp_verbose >= 1) bb_simple_info_msg(msg); } while (0) |
| void log1s(const char *msg) FAST_FUNC; |
| # if CONFIG_UDHCP_DEBUG >= 2 |
| void udhcp_dump_packet(struct dhcp_packet *packet) FAST_FUNC; |
| # define log2(...) do { if (dhcp_verbose >= 2) bb_info_msg(__VA_ARGS__); } while (0) |
| # define log2s(msg) do { if (dhcp_verbose >= 2) bb_simple_info_msg(msg); } while (0) |
| # else |
| # define udhcp_dump_packet(...) ((void)0) |
| # define log2(...) ((void)0) |
| # define log2s(msg) ((void)0) |
| # endif |
| # if CONFIG_UDHCP_DEBUG >= 3 |
| # define log3(...) do { if (dhcp_verbose >= 3) bb_info_msg(__VA_ARGS__); } while (0) |
| # define log3s(msg) do { if (dhcp_verbose >= 3) bb_simple_info_msg(msg); } while (0) |
| # else |
| # define log3(...) ((void)0) |
| # define log3s(msg) ((void)0) |
| # endif |
| #else |
| # define IF_UDHCP_VERBOSE(...) |
| # define udhcp_dump_packet(...) ((void)0) |
| # define log1(...) ((void)0) |
| # define log1s(msg) ((void)0) |
| # define log2(...) ((void)0) |
| # define log2s(msg) ((void)0) |
| # define log3(...) ((void)0) |
| # define log3s(msg) ((void)0) |
| #endif |
| |
| /*** Other shared functions ***/ |
| |
| /* 2nd param is "uint32_t*" */ |
| int FAST_FUNC udhcp_str2nip(const char *str, void *arg); |
| |
| #if !ENABLE_UDHCPC6 |
| #define udhcp_insert_new_option(opt_list, code, length, dhcpv6) \ |
| udhcp_insert_new_option(opt_list, code, length) |
| #endif |
| void* FAST_FUNC udhcp_insert_new_option(struct option_set **opt_list, |
| unsigned code, |
| unsigned length, |
| bool dhcpv6); |
| |
| /* 2nd param is "struct option_set**" */ |
| #if !ENABLE_UDHCPC6 |
| #define udhcp_str2optset(str, arg, optflags, option_strings, dhcpv6) \ |
| udhcp_str2optset(str, arg, optflags, option_strings) |
| #endif |
| int FAST_FUNC udhcp_str2optset(const char *str, |
| void *arg, |
| const struct dhcp_optflag *optflags, |
| const char *option_strings, |
| bool dhcpv6); |
| |
| #if ENABLE_UDHCPC || ENABLE_UDHCPD |
| void udhcp_init_header(struct dhcp_packet *packet, char type) FAST_FUNC; |
| #endif |
| |
| int udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd) FAST_FUNC; |
| |
| int udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt, |
| uint32_t source_nip, int source_port, |
| uint32_t dest_nip, int dest_port, const uint8_t *dest_arp, |
| int ifindex) FAST_FUNC; |
| |
| int udhcp_send_kernel_packet(struct dhcp_packet *dhcp_pkt, |
| uint32_t source_nip, int source_port, |
| uint32_t dest_nip, int dest_port, |
| const char *ifname) FAST_FUNC; |
| |
| void udhcp_sp_setup(void) FAST_FUNC; |
| void udhcp_sp_fd_set(struct pollfd *pfds, int extra_fd) FAST_FUNC; |
| int udhcp_sp_read(void) FAST_FUNC; |
| |
| int udhcp_read_interface(const char *interface, |
| int *ifindex, uint32_t *nip, uint8_t *mac) FAST_FUNC; |
| |
| int udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf) FAST_FUNC; |
| |
| /* Returns 1 if no reply received */ |
| int arpping(uint32_t test_nip, |
| const uint8_t *safe_mac, |
| uint32_t from_ip, |
| uint8_t *from_mac, |
| const char *interface, |
| unsigned timeo) FAST_FUNC; |
| |
| /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */ |
| int sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip) FAST_FUNC; |
| |
| POP_SAVED_FUNCTION_VISIBILITY |
| |
| #endif |