diff options
Diffstat (limited to 'print-ip.c')
-rw-r--r-- | print-ip.c | 720 |
1 files changed, 720 insertions, 0 deletions
diff --git a/print-ip.c b/print-ip.c new file mode 100644 index 000000000000..bb1554f9d133 --- /dev/null +++ b/print-ip.c @@ -0,0 +1,720 @@ +/* + * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code distributions + * retain the above copyright notice and this paragraph in its entirety, (2) + * distributions including binary code include the above copyright notice and + * this paragraph in its entirety in the documentation or other materials + * provided with the distribution, and (3) all advertising materials mentioning + * features or use of this software display the following acknowledgement: + * ``This product includes software developed by the University of California, + * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of + * the University nor the names of its contributors may be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +/* \summary: IP printer */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <netdissect-stdinc.h> + +#include <string.h> + +#include "netdissect.h" +#include "addrtoname.h" +#include "extract.h" + +#include "ip.h" +#include "ipproto.h" + +static const char tstr[] = "[|ip]"; + +static const struct tok ip_option_values[] = { + { IPOPT_EOL, "EOL" }, + { IPOPT_NOP, "NOP" }, + { IPOPT_TS, "timestamp" }, + { IPOPT_SECURITY, "security" }, + { IPOPT_RR, "RR" }, + { IPOPT_SSRR, "SSRR" }, + { IPOPT_LSRR, "LSRR" }, + { IPOPT_RA, "RA" }, + { IPOPT_RFC1393, "traceroute" }, + { 0, NULL } +}; + +/* + * print the recorded route in an IP RR, LSRR or SSRR option. + */ +static void +ip_printroute(netdissect_options *ndo, + register const u_char *cp, u_int length) +{ + register u_int ptr; + register u_int len; + + if (length < 3) { + ND_PRINT((ndo, " [bad length %u]", length)); + return; + } + if ((length + 1) & 3) + ND_PRINT((ndo, " [bad length %u]", length)); + ptr = cp[2] - 1; + if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1) + ND_PRINT((ndo, " [bad ptr %u]", cp[2])); + + for (len = 3; len < length; len += 4) { + ND_PRINT((ndo, " %s", ipaddr_string(ndo, &cp[len]))); + if (ptr > len) + ND_PRINT((ndo, ",")); + } +} + +/* + * If source-routing is present and valid, return the final destination. + * Otherwise, return IP destination. + * + * This is used for UDP and TCP pseudo-header in the checksum + * calculation. + */ +static uint32_t +ip_finddst(netdissect_options *ndo, + const struct ip *ip) +{ + int length; + int len; + const u_char *cp; + uint32_t retval; + + cp = (const u_char *)(ip + 1); + length = (IP_HL(ip) << 2) - sizeof(struct ip); + + for (; length > 0; cp += len, length -= len) { + int tt; + + ND_TCHECK(*cp); + tt = *cp; + if (tt == IPOPT_EOL) + break; + else if (tt == IPOPT_NOP) + len = 1; + else { + ND_TCHECK(cp[1]); + len = cp[1]; + if (len < 2) + break; + } + ND_TCHECK2(*cp, len); + switch (tt) { + + case IPOPT_SSRR: + case IPOPT_LSRR: + if (len < 7) + break; + UNALIGNED_MEMCPY(&retval, cp + len - 4, 4); + return retval; + } + } +trunc: + UNALIGNED_MEMCPY(&retval, &ip->ip_dst, sizeof(uint32_t)); + return retval; +} + +/* + * Compute a V4-style checksum by building a pseudoheader. + */ +int +nextproto4_cksum(netdissect_options *ndo, + const struct ip *ip, const uint8_t *data, + u_int len, u_int covlen, u_int next_proto) +{ + struct phdr { + uint32_t src; + uint32_t dst; + u_char mbz; + u_char proto; + uint16_t len; + } ph; + struct cksum_vec vec[2]; + + /* pseudo-header.. */ + ph.len = htons((uint16_t)len); + ph.mbz = 0; + ph.proto = next_proto; + UNALIGNED_MEMCPY(&ph.src, &ip->ip_src, sizeof(uint32_t)); + if (IP_HL(ip) == 5) + UNALIGNED_MEMCPY(&ph.dst, &ip->ip_dst, sizeof(uint32_t)); + else + ph.dst = ip_finddst(ndo, ip); + + vec[0].ptr = (const uint8_t *)(void *)&ph; + vec[0].len = sizeof(ph); + vec[1].ptr = data; + vec[1].len = covlen; + return (in_cksum(vec, 2)); +} + +static void +ip_printts(netdissect_options *ndo, + register const u_char *cp, u_int length) +{ + register u_int ptr; + register u_int len; + int hoplen; + const char *type; + + if (length < 4) { + ND_PRINT((ndo, "[bad length %u]", length)); + return; + } + ND_PRINT((ndo, " TS{")); + hoplen = ((cp[3]&0xF) != IPOPT_TS_TSONLY) ? 8 : 4; + if ((length - 4) & (hoplen-1)) + ND_PRINT((ndo, "[bad length %u]", length)); + ptr = cp[2] - 1; + len = 0; + if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1) + ND_PRINT((ndo, "[bad ptr %u]", cp[2])); + switch (cp[3]&0xF) { + case IPOPT_TS_TSONLY: + ND_PRINT((ndo, "TSONLY")); + break; + case IPOPT_TS_TSANDADDR: + ND_PRINT((ndo, "TS+ADDR")); + break; + /* + * prespecified should really be 3, but some ones might send 2 + * instead, and the IPOPT_TS_PRESPEC constant can apparently + * have both values, so we have to hard-code it here. + */ + + case 2: + ND_PRINT((ndo, "PRESPEC2.0")); + break; + case 3: /* IPOPT_TS_PRESPEC */ + ND_PRINT((ndo, "PRESPEC")); + break; + default: + ND_PRINT((ndo, "[bad ts type %d]", cp[3]&0xF)); + goto done; + } + + type = " "; + for (len = 4; len < length; len += hoplen) { + if (ptr == len) + type = " ^ "; + ND_PRINT((ndo, "%s%d@%s", type, EXTRACT_32BITS(&cp[len+hoplen-4]), + hoplen!=8 ? "" : ipaddr_string(ndo, &cp[len]))); + type = " "; + } + +done: + ND_PRINT((ndo, "%s", ptr == len ? " ^ " : "")); + + if (cp[3]>>4) + ND_PRINT((ndo, " [%d hops not recorded]} ", cp[3]>>4)); + else + ND_PRINT((ndo, "}")); +} + +/* + * print IP options. + */ +static void +ip_optprint(netdissect_options *ndo, + register const u_char *cp, u_int length) +{ + register u_int option_len; + const char *sep = ""; + + for (; length > 0; cp += option_len, length -= option_len) { + u_int option_code; + + ND_PRINT((ndo, "%s", sep)); + sep = ","; + + ND_TCHECK(*cp); + option_code = *cp; + + ND_PRINT((ndo, "%s", + tok2str(ip_option_values,"unknown %u",option_code))); + + if (option_code == IPOPT_NOP || + option_code == IPOPT_EOL) + option_len = 1; + + else { + ND_TCHECK(cp[1]); + option_len = cp[1]; + if (option_len < 2) { + ND_PRINT((ndo, " [bad length %u]", option_len)); + return; + } + } + + if (option_len > length) { + ND_PRINT((ndo, " [bad length %u]", option_len)); + return; + } + + ND_TCHECK2(*cp, option_len); + + switch (option_code) { + case IPOPT_EOL: + return; + + case IPOPT_TS: + ip_printts(ndo, cp, option_len); + break; + + case IPOPT_RR: /* fall through */ + case IPOPT_SSRR: + case IPOPT_LSRR: + ip_printroute(ndo, cp, option_len); + break; + + case IPOPT_RA: + if (option_len < 4) { + ND_PRINT((ndo, " [bad length %u]", option_len)); + break; + } + ND_TCHECK(cp[3]); + if (EXTRACT_16BITS(&cp[2]) != 0) + ND_PRINT((ndo, " value %u", EXTRACT_16BITS(&cp[2]))); + break; + + case IPOPT_NOP: /* nothing to print - fall through */ + case IPOPT_SECURITY: + default: + break; + } + } + return; + +trunc: + ND_PRINT((ndo, "%s", tstr)); +} + +#define IP_RES 0x8000 + +static const struct tok ip_frag_values[] = { + { IP_MF, "+" }, + { IP_DF, "DF" }, + { IP_RES, "rsvd" }, /* The RFC3514 evil ;-) bit */ + { 0, NULL } +}; + +struct ip_print_demux_state { + const struct ip *ip; + const u_char *cp; + u_int len, off; + u_char nh; + int advance; +}; + +static void +ip_print_demux(netdissect_options *ndo, + struct ip_print_demux_state *ipds) +{ + struct protoent *proto; + +again: + switch (ipds->nh) { + + case IPPROTO_AH: + if (!ND_TTEST(*ipds->cp)) { + ND_PRINT((ndo, "[|AH]")); + break; + } + ipds->nh = *ipds->cp; + ipds->advance = ah_print(ndo, ipds->cp); + if (ipds->advance <= 0) + break; + ipds->cp += ipds->advance; + ipds->len -= ipds->advance; + goto again; + + case IPPROTO_ESP: + { + int enh, padlen; + ipds->advance = esp_print(ndo, ipds->cp, ipds->len, + (const u_char *)ipds->ip, + &enh, &padlen); + if (ipds->advance <= 0) + break; + ipds->cp += ipds->advance; + ipds->len -= ipds->advance + padlen; + ipds->nh = enh & 0xff; + goto again; + } + + case IPPROTO_IPCOMP: + { + ipcomp_print(ndo, ipds->cp); + /* + * Either this has decompressed the payload and + * printed it, in which case there's nothing more + * to do, or it hasn't, in which case there's + * nothing more to do. + */ + break; + } + + case IPPROTO_SCTP: + sctp_print(ndo, ipds->cp, (const u_char *)ipds->ip, ipds->len); + break; + + case IPPROTO_DCCP: + dccp_print(ndo, ipds->cp, (const u_char *)ipds->ip, ipds->len); + break; + + case IPPROTO_TCP: + /* pass on the MF bit plus the offset to detect fragments */ + tcp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip, + ipds->off & (IP_MF|IP_OFFMASK)); + break; + + case IPPROTO_UDP: + /* pass on the MF bit plus the offset to detect fragments */ + udp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip, + ipds->off & (IP_MF|IP_OFFMASK)); + break; + + case IPPROTO_ICMP: + /* pass on the MF bit plus the offset to detect fragments */ + icmp_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip, + ipds->off & (IP_MF|IP_OFFMASK)); + break; + + case IPPROTO_PIGP: + /* + * XXX - the current IANA protocol number assignments + * page lists 9 as "any private interior gateway + * (used by Cisco for their IGRP)" and 88 as + * "EIGRP" from Cisco. + * + * Recent BSD <netinet/in.h> headers define + * IP_PROTO_PIGP as 9 and IP_PROTO_IGRP as 88. + * We define IP_PROTO_PIGP as 9 and + * IP_PROTO_EIGRP as 88; those names better + * match was the current protocol number + * assignments say. + */ + igrp_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_EIGRP: + eigrp_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_ND: + ND_PRINT((ndo, " nd %d", ipds->len)); + break; + + case IPPROTO_EGP: + egp_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_OSPF: + ospf_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip); + break; + + case IPPROTO_IGMP: + igmp_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_IPV4: + /* DVMRP multicast tunnel (ip-in-ip encapsulation) */ + ip_print(ndo, ipds->cp, ipds->len); + if (! ndo->ndo_vflag) { + ND_PRINT((ndo, " (ipip-proto-4)")); + return; + } + break; + + case IPPROTO_IPV6: + /* ip6-in-ip encapsulation */ + ip6_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_RSVP: + rsvp_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_GRE: + /* do it */ + gre_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_MOBILE: + mobile_print(ndo, ipds->cp, ipds->len); + break; + + case IPPROTO_PIM: + pim_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip); + break; + + case IPPROTO_VRRP: + if (ndo->ndo_packettype == PT_CARP) { + if (ndo->ndo_vflag) + ND_PRINT((ndo, "carp %s > %s: ", + ipaddr_string(ndo, &ipds->ip->ip_src), + ipaddr_string(ndo, &ipds->ip->ip_dst))); + carp_print(ndo, ipds->cp, ipds->len, ipds->ip->ip_ttl); + } else { + if (ndo->ndo_vflag) + ND_PRINT((ndo, "vrrp %s > %s: ", + ipaddr_string(ndo, &ipds->ip->ip_src), + ipaddr_string(ndo, &ipds->ip->ip_dst))); + vrrp_print(ndo, ipds->cp, ipds->len, + (const u_char *)ipds->ip, ipds->ip->ip_ttl); + } + break; + + case IPPROTO_PGM: + pgm_print(ndo, ipds->cp, ipds->len, (const u_char *)ipds->ip); + break; + + default: + if (ndo->ndo_nflag==0 && (proto = getprotobynumber(ipds->nh)) != NULL) + ND_PRINT((ndo, " %s", proto->p_name)); + else + ND_PRINT((ndo, " ip-proto-%d", ipds->nh)); + ND_PRINT((ndo, " %d", ipds->len)); + break; + } +} + +void +ip_print_inner(netdissect_options *ndo, + const u_char *bp, + u_int length, u_int nh, + const u_char *bp2) +{ + struct ip_print_demux_state ipd; + + ipd.ip = (const struct ip *)bp2; + ipd.cp = bp; + ipd.len = length; + ipd.off = 0; + ipd.nh = nh; + ipd.advance = 0; + + ip_print_demux(ndo, &ipd); +} + + +/* + * print an IP datagram. + */ +void +ip_print(netdissect_options *ndo, + const u_char *bp, + u_int length) +{ + struct ip_print_demux_state ipd; + struct ip_print_demux_state *ipds=&ipd; + const u_char *ipend; + u_int hlen; + struct cksum_vec vec[1]; + uint16_t sum, ip_sum; + struct protoent *proto; + + ipds->ip = (const struct ip *)bp; + ND_TCHECK(ipds->ip->ip_vhl); + if (IP_V(ipds->ip) != 4) { /* print version and fail if != 4 */ + if (IP_V(ipds->ip) == 6) + ND_PRINT((ndo, "IP6, wrong link-layer encapsulation ")); + else + ND_PRINT((ndo, "IP%u ", IP_V(ipds->ip))); + return; + } + if (!ndo->ndo_eflag) + ND_PRINT((ndo, "IP ")); + + ND_TCHECK(*ipds->ip); + if (length < sizeof (struct ip)) { + ND_PRINT((ndo, "truncated-ip %u", length)); + return; + } + hlen = IP_HL(ipds->ip) * 4; + if (hlen < sizeof (struct ip)) { + ND_PRINT((ndo, "bad-hlen %u", hlen)); + return; + } + + ipds->len = EXTRACT_16BITS(&ipds->ip->ip_len); + if (length < ipds->len) + ND_PRINT((ndo, "truncated-ip - %u bytes missing! ", + ipds->len - length)); + if (ipds->len < hlen) { +#ifdef GUESS_TSO + if (ipds->len) { + ND_PRINT((ndo, "bad-len %u", ipds->len)); + return; + } + else { + /* we guess that it is a TSO send */ + ipds->len = length; + } +#else + ND_PRINT((ndo, "bad-len %u", ipds->len)); + return; +#endif /* GUESS_TSO */ + } + + /* + * Cut off the snapshot length to the end of the IP payload. + */ + ipend = bp + ipds->len; + if (ipend < ndo->ndo_snapend) + ndo->ndo_snapend = ipend; + + ipds->len -= hlen; + + ipds->off = EXTRACT_16BITS(&ipds->ip->ip_off); + + if (ndo->ndo_vflag) { + ND_PRINT((ndo, "(tos 0x%x", (int)ipds->ip->ip_tos)); + /* ECN bits */ + switch (ipds->ip->ip_tos & 0x03) { + + case 0: + break; + + case 1: + ND_PRINT((ndo, ",ECT(1)")); + break; + + case 2: + ND_PRINT((ndo, ",ECT(0)")); + break; + + case 3: + ND_PRINT((ndo, ",CE")); + break; + } + + if (ipds->ip->ip_ttl >= 1) + ND_PRINT((ndo, ", ttl %u", ipds->ip->ip_ttl)); + + /* + * for the firewall guys, print id, offset. + * On all but the last stick a "+" in the flags portion. + * For unfragmented datagrams, note the don't fragment flag. + */ + + ND_PRINT((ndo, ", id %u, offset %u, flags [%s], proto %s (%u)", + EXTRACT_16BITS(&ipds->ip->ip_id), + (ipds->off & 0x1fff) * 8, + bittok2str(ip_frag_values, "none", ipds->off&0xe000), + tok2str(ipproto_values,"unknown",ipds->ip->ip_p), + ipds->ip->ip_p)); + + ND_PRINT((ndo, ", length %u", EXTRACT_16BITS(&ipds->ip->ip_len))); + + if ((hlen - sizeof(struct ip)) > 0) { + ND_PRINT((ndo, ", options (")); + ip_optprint(ndo, (const u_char *)(ipds->ip + 1), hlen - sizeof(struct ip)); + ND_PRINT((ndo, ")")); + } + + if (!ndo->ndo_Kflag && (const u_char *)ipds->ip + hlen <= ndo->ndo_snapend) { + vec[0].ptr = (const uint8_t *)(const void *)ipds->ip; + vec[0].len = hlen; + sum = in_cksum(vec, 1); + if (sum != 0) { + ip_sum = EXTRACT_16BITS(&ipds->ip->ip_sum); + ND_PRINT((ndo, ", bad cksum %x (->%x)!", ip_sum, + in_cksum_shouldbe(ip_sum, sum))); + } + } + + ND_PRINT((ndo, ")\n ")); + } + + /* + * If this is fragment zero, hand it to the next higher + * level protocol. + */ + if ((ipds->off & 0x1fff) == 0) { + ipds->cp = (const u_char *)ipds->ip + hlen; + ipds->nh = ipds->ip->ip_p; + + if (ipds->nh != IPPROTO_TCP && ipds->nh != IPPROTO_UDP && + ipds->nh != IPPROTO_SCTP && ipds->nh != IPPROTO_DCCP) { + ND_PRINT((ndo, "%s > %s: ", + ipaddr_string(ndo, &ipds->ip->ip_src), + ipaddr_string(ndo, &ipds->ip->ip_dst))); + } + ip_print_demux(ndo, ipds); + } else { + /* + * Ultra quiet now means that all this stuff should be + * suppressed. + */ + if (ndo->ndo_qflag > 1) + return; + + /* + * This isn't the first frag, so we're missing the + * next level protocol header. print the ip addr + * and the protocol. + */ + ND_PRINT((ndo, "%s > %s:", ipaddr_string(ndo, &ipds->ip->ip_src), + ipaddr_string(ndo, &ipds->ip->ip_dst))); + if (!ndo->ndo_nflag && (proto = getprotobynumber(ipds->ip->ip_p)) != NULL) + ND_PRINT((ndo, " %s", proto->p_name)); + else + ND_PRINT((ndo, " ip-proto-%d", ipds->ip->ip_p)); + } + return; + +trunc: + ND_PRINT((ndo, "%s", tstr)); + return; +} + +void +ipN_print(netdissect_options *ndo, register const u_char *bp, register u_int length) +{ + if (length < 1) { + ND_PRINT((ndo, "truncated-ip %d", length)); + return; + } + + ND_TCHECK(*bp); + switch (*bp & 0xF0) { + case 0x40: + ip_print (ndo, bp, length); + break; + case 0x60: + ip6_print (ndo, bp, length); + break; + default: + ND_PRINT((ndo, "unknown ip %d", (*bp & 0xF0) >> 4)); + break; + } + return; + +trunc: + ND_PRINT((ndo, "%s", tstr)); + return; +} + +/* + * Local Variables: + * c-style: whitesmith + * c-basic-offset: 8 + * End: + */ + + |