From 7adcb5b605cc1328a3084c334f4697ec9771936c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 15 Apr 2024 19:13:01 +0200 Subject: Adding upstream version 4.99.4. Signed-off-by: Daniel Baumann --- print-ip.c | 538 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 538 insertions(+) create mode 100644 print-ip.c (limited to 'print-ip.c') diff --git a/print-ip.c b/print-ip.c new file mode 100644 index 0000000..23ba99c --- /dev/null +++ b/print-ip.c @@ -0,0 +1,538 @@ +/* + * 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 +#endif + +#include "netdissect-stdinc.h" + +#include "netdissect.h" +#include "addrtoname.h" +#include "extract.h" + +#include "ip.h" +#include "ipproto.h" + + +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, + const u_char *cp, u_int length) +{ + u_int ptr; + u_int len; + + if (length < 3) { + ND_PRINT(" [bad length %u]", length); + return (0); + } + if ((length + 1) & 3) + ND_PRINT(" [bad length %u]", length); + ptr = GET_U_1(cp + 2) - 1; + if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1) + ND_PRINT(" [bad ptr %u]", GET_U_1(cp + 2)); + + for (len = 3; len < length; len += 4) { + ND_TCHECK_4(cp + len); /* Needed to print the IP addresses */ + ND_PRINT(" %s", GET_IPADDR_STRING(cp + len)); + if (ptr > len) + ND_PRINT(","); + } + 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) +{ + u_int length; + u_int len; + const u_char *cp; + + cp = (const u_char *)(ip + 1); + length = IP_HL(ip) * 4; + if (length < sizeof(struct ip)) + goto trunc; + length -= sizeof(struct ip); + + for (; length != 0; cp += len, length -= len) { + int tt; + + tt = GET_U_1(cp); + if (tt == IPOPT_EOL) + break; + else if (tt == IPOPT_NOP) + len = 1; + else { + len = GET_U_1(cp + 1); + if (len < 2) + break; + } + if (length < len) + goto trunc; + ND_TCHECK_LEN(cp, len); + switch (tt) { + + case IPOPT_SSRR: + case IPOPT_LSRR: + if (len < 7) + break; + return (GET_IPV4_TO_NETWORK_ORDER(cp + len - 4)); + } + } +trunc: + return (GET_IPV4_TO_NETWORK_ORDER(ip->ip_dst)); +} + +/* + * Compute a V4-style checksum by building a pseudoheader. + */ +uint16_t +nextproto4_cksum(netdissect_options *ndo, + const struct ip *ip, const uint8_t *data, + u_int len, u_int covlen, uint8_t next_proto) +{ + struct phdr { + uint32_t src; + uint32_t dst; + uint8_t mbz; + uint8_t 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; + ph.src = GET_IPV4_TO_NETWORK_ORDER(ip->ip_src); + if (IP_HL(ip) == 5) + ph.dst = GET_IPV4_TO_NETWORK_ORDER(ip->ip_dst); + 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, + const u_char *cp, u_int length) +{ + u_int ptr; + u_int len; + u_int hoplen; + const char *type; + + if (length < 4) { + ND_PRINT("[bad length %u]", length); + return (0); + } + ND_PRINT(" TS{"); + hoplen = ((GET_U_1(cp + 3) & 0xF) != IPOPT_TS_TSONLY) ? 8 : 4; + if ((length - 4) & (hoplen-1)) + ND_PRINT("[bad length %u]", length); + ptr = GET_U_1(cp + 2) - 1; + len = 0; + if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1) + ND_PRINT("[bad ptr %u]", GET_U_1(cp + 2)); + switch (GET_U_1(cp + 3)&0xF) { + case IPOPT_TS_TSONLY: + ND_PRINT("TSONLY"); + break; + case IPOPT_TS_TSANDADDR: + ND_PRINT("TS+ADDR"); + break; + case IPOPT_TS_PRESPEC: + ND_PRINT("PRESPEC"); + break; + default: + ND_PRINT("[bad ts type %u]", GET_U_1(cp + 3)&0xF); + goto done; + } + + type = " "; + for (len = 4; len < length; len += hoplen) { + if (ptr == len) + type = " ^ "; + ND_TCHECK_LEN(cp + len, hoplen); + ND_PRINT("%s%u@%s", type, GET_BE_U_4(cp + len + hoplen - 4), + hoplen!=8 ? "" : GET_IPADDR_STRING(cp + len)); + type = " "; + } + +done: + ND_PRINT("%s", ptr == len ? " ^ " : ""); + + if (GET_U_1(cp + 3) >> 4) + ND_PRINT(" [%u hops not recorded]} ", GET_U_1(cp + 3)>>4); + else + ND_PRINT("}"); + return (0); + +trunc: + return (-1); +} + +/* + * print IP options. + If truncated return -1, else 0. + */ +static int +ip_optprint(netdissect_options *ndo, + const u_char *cp, u_int length) +{ + u_int option_len; + const char *sep = ""; + + for (; length > 0; cp += option_len, length -= option_len) { + u_int option_code; + + ND_PRINT("%s", sep); + sep = ","; + + option_code = GET_U_1(cp); + + ND_PRINT("%s", + tok2str(ip_option_values,"unknown %u",option_code)); + + if (option_code == IPOPT_NOP || + option_code == IPOPT_EOL) + option_len = 1; + + else { + option_len = GET_U_1(cp + 1); + if (option_len < 2) { + ND_PRINT(" [bad length %u]", option_len); + return 0; + } + } + + if (option_len > length) { + ND_PRINT(" [bad length %u]", option_len); + return 0; + } + + ND_TCHECK_LEN(cp, option_len); + + switch (option_code) { + case IPOPT_EOL: + return 0; + + 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(" [bad length %u]", option_len); + break; + } + ND_TCHECK_1(cp + 3); + if (GET_BE_U_2(cp + 2) != 0) + ND_PRINT(" value %u", GET_BE_U_2(cp + 2)); + break; + + case IPOPT_NOP: /* nothing to print - fall through */ + case IPOPT_SECURITY: + default: + break; + } + } + return 0; + +trunc: + return -1; +} + +#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 } +}; + + +/* + * print an IP datagram. + */ +void +ip_print(netdissect_options *ndo, + const u_char *bp, + u_int length) +{ + const struct ip *ip; + u_int off; + u_int hlen; + u_int len; + struct cksum_vec vec[1]; + uint8_t ip_tos, ip_ttl, ip_proto; + uint16_t sum, ip_sum; + const char *p_name; + int truncated = 0; + + ndo->ndo_protocol = "ip"; + ip = (const struct ip *)bp; + if (IP_V(ip) != 4) { /* print version and fail if != 4 */ + if (IP_V(ip) == 6) + ND_PRINT("IP6, wrong link-layer encapsulation"); + else + ND_PRINT("IP%u", IP_V(ip)); + nd_print_invalid(ndo); + return; + } + if (!ndo->ndo_eflag) + ND_PRINT("IP "); + + ND_TCHECK_SIZE(ip); + if (length < sizeof (struct ip)) { + ND_PRINT("truncated-ip %u", length); + return; + } + hlen = IP_HL(ip) * 4; + if (hlen < sizeof (struct ip)) { + ND_PRINT("bad-hlen %u", hlen); + return; + } + + len = GET_BE_U_2(ip->ip_len); + if (length < len) + ND_PRINT("truncated-ip - %u bytes missing! ", + len - length); + if (len < hlen) { +#ifdef GUESS_TSO + if (len) { + ND_PRINT("bad-len %u", len); + return; + } + else { + /* we guess that it is a TSO send */ + len = length; + } +#else + ND_PRINT("bad-len %u", len); + return; +#endif /* GUESS_TSO */ + } + + /* + * Cut off the snapshot length to the end of the IP payload. + */ + if (!nd_push_snaplen(ndo, bp, len)) { + (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC, + "%s: can't push snaplen on buffer stack", __func__); + } + + len -= hlen; + + off = GET_BE_U_2(ip->ip_off); + + ip_proto = GET_U_1(ip->ip_p); + + if (ndo->ndo_vflag) { + ip_tos = GET_U_1(ip->ip_tos); + ND_PRINT("(tos 0x%x", ip_tos); + /* ECN bits */ + switch (ip_tos & 0x03) { + + case 0: + break; + + case 1: + ND_PRINT(",ECT(1)"); + break; + + case 2: + ND_PRINT(",ECT(0)"); + break; + + case 3: + ND_PRINT(",CE"); + break; + } + + ip_ttl = GET_U_1(ip->ip_ttl); + if (ip_ttl >= 1) + ND_PRINT(", ttl %u", 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(", id %u, offset %u, flags [%s], proto %s (%u)", + GET_BE_U_2(ip->ip_id), + (off & IP_OFFMASK) * 8, + bittok2str(ip_frag_values, "none", off & (IP_RES|IP_DF|IP_MF)), + tok2str(ipproto_values, "unknown", ip_proto), + ip_proto); + + ND_PRINT(", length %u", GET_BE_U_2(ip->ip_len)); + + if ((hlen - sizeof(struct ip)) > 0) { + ND_PRINT(", options ("); + if (ip_optprint(ndo, (const u_char *)(ip + 1), + hlen - sizeof(struct ip)) == -1) { + ND_PRINT(" [truncated-option]"); + truncated = 1; + } + ND_PRINT(")"); + } + + if (!ndo->ndo_Kflag && (const u_char *)ip + hlen <= ndo->ndo_snapend) { + vec[0].ptr = (const uint8_t *)(const void *)ip; + vec[0].len = hlen; + sum = in_cksum(vec, 1); + if (sum != 0) { + ip_sum = GET_BE_U_2(ip->ip_sum); + ND_PRINT(", bad cksum %x (->%x)!", ip_sum, + in_cksum_shouldbe(ip_sum, sum)); + } + } + + ND_PRINT(")\n "); + if (truncated) { + ND_PRINT("%s > %s: ", + GET_IPADDR_STRING(ip->ip_src), + GET_IPADDR_STRING(ip->ip_dst)); + nd_print_trunc(ndo); + nd_pop_packet_info(ndo); + return; + } + } + + /* + * If this is fragment zero, hand it to the next higher + * level protocol. Let them know whether there are more + * fragments. + */ + if ((off & IP_OFFMASK) == 0) { + uint8_t nh = GET_U_1(ip->ip_p); + + if (nh != IPPROTO_TCP && nh != IPPROTO_UDP && + nh != IPPROTO_SCTP && nh != IPPROTO_DCCP) { + ND_PRINT("%s > %s: ", + GET_IPADDR_STRING(ip->ip_src), + GET_IPADDR_STRING(ip->ip_dst)); + } + /* + * Do a bounds check before calling ip_demux_print(). + * At least the header data is required. + */ + if (!ND_TTEST_LEN((const u_char *)ip, hlen)) { + ND_PRINT(" [remaining caplen(%u) < header length(%u)]", + ND_BYTES_AVAILABLE_AFTER((const u_char *)ip), + hlen); + nd_trunc_longjmp(ndo); + } + ip_demux_print(ndo, (const u_char *)ip + hlen, len, 4, + off & IP_MF, GET_U_1(ip->ip_ttl), nh, bp); + } else { + /* + * Ultra quiet now means that all this stuff should be + * suppressed. + */ + if (ndo->ndo_qflag > 1) { + nd_pop_packet_info(ndo); + 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("%s > %s:", GET_IPADDR_STRING(ip->ip_src), + GET_IPADDR_STRING(ip->ip_dst)); + if (!ndo->ndo_nflag && (p_name = netdb_protoname(ip_proto)) != NULL) + ND_PRINT(" %s", p_name); + else + ND_PRINT(" ip-proto-%u", ip_proto); + } + nd_pop_packet_info(ndo); + return; + +trunc: + nd_print_trunc(ndo); +} + +void +ipN_print(netdissect_options *ndo, const u_char *bp, u_int length) +{ + ndo->ndo_protocol = "ipn"; + if (length < 1) { + ND_PRINT("truncated-ip %u", length); + return; + } + + switch (GET_U_1(bp) & 0xF0) { + case 0x40: + ip_print(ndo, bp, length); + break; + case 0x60: + ip6_print(ndo, bp, length); + break; + default: + ND_PRINT("unknown ip %u", (GET_U_1(bp) & 0xF0) >> 4); + break; + } +} -- cgit v1.2.3