/* * 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 int 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 (0); } if ((length + 1) & 3) ND_PRINT((ndo, " [bad length %u]", length)); ND_TCHECK(cp[2]); 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_TCHECK2(cp[len], 4); ND_PRINT((ndo, " %s", ipaddr_string(ndo, &cp[len]))); if (ptr > len) ND_PRINT((ndo, ",")); } return (0); trunc: return (-1); } /* * 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 int 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 (0); } 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)); ND_TCHECK(cp[2]); ptr = cp[2] - 1; len = 0; if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1) ND_PRINT((ndo, "[bad ptr %u]", cp[2])); ND_TCHECK(cp[3]); 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_TCHECK2(cp[len], hoplen); 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, "}")); return (0); trunc: return (-1); } /* * 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: if (ip_printts(ndo, cp, option_len) == -1) goto trunc; break; case IPOPT_RR: /* fall through */ case IPOPT_SSRR: case IPOPT_LSRR: if (ip_printroute(ndo, cp, option_len) == -1) goto trunc; 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) { const char *p_name; 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 && (p_name = netdb_protoname(ipds->nh)) != NULL) ND_PRINT((ndo, " %s", 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; const char *p_name; 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 && (p_name = netdb_protoname(ipds->ip->ip_p)) != NULL) ND_PRINT((ndo, " %s", 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: */