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-rw-r--r--print-tcp.c972
1 files changed, 972 insertions, 0 deletions
diff --git a/print-tcp.c b/print-tcp.c
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index 0000000..72964eb
--- /dev/null
+++ b/print-tcp.c
@@ -0,0 +1,972 @@
+/* $NetBSD: print-tcp.c,v 1.9 2007/07/26 18:15:12 plunky Exp $ */
+
+/*
+ * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Copyright (c) 1999-2004 The tcpdump.org project
+ *
+ * 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: TCP printer */
+
+#ifndef lint
+#else
+__RCSID("$NetBSD: print-tcp.c,v 1.8 2007/07/24 11:53:48 drochner Exp $");
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "netdissect-stdinc.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "netdissect.h"
+#include "addrtoname.h"
+#include "extract.h"
+
+#include "diag-control.h"
+
+#include "tcp.h"
+
+#include "ip.h"
+#include "ip6.h"
+#include "ipproto.h"
+#include "rpc_auth.h"
+#include "rpc_msg.h"
+
+#ifdef HAVE_LIBCRYPTO
+#include <openssl/md5.h>
+#include "signature.h"
+
+static int tcp_verify_signature(netdissect_options *ndo,
+ const struct ip *ip, const struct tcphdr *tp,
+ const u_char *data, u_int length, const u_char *rcvsig);
+#endif
+
+static void print_tcp_rst_data(netdissect_options *, const u_char *sp, u_int length);
+static void print_tcp_fastopen_option(netdissect_options *ndo, const u_char *cp,
+ u_int datalen, int exp);
+
+#define MAX_RST_DATA_LEN 30
+
+
+struct tha {
+ nd_ipv4 src;
+ nd_ipv4 dst;
+ u_int port;
+};
+
+struct tcp_seq_hash {
+ struct tcp_seq_hash *nxt;
+ struct tha addr;
+ uint32_t seq;
+ uint32_t ack;
+};
+
+struct tha6 {
+ nd_ipv6 src;
+ nd_ipv6 dst;
+ u_int port;
+};
+
+struct tcp_seq_hash6 {
+ struct tcp_seq_hash6 *nxt;
+ struct tha6 addr;
+ uint32_t seq;
+ uint32_t ack;
+};
+
+#define TSEQ_HASHSIZE 919
+
+/* These tcp options do not have the size octet */
+#define ZEROLENOPT(o) ((o) == TCPOPT_EOL || (o) == TCPOPT_NOP)
+
+static struct tcp_seq_hash tcp_seq_hash4[TSEQ_HASHSIZE];
+static struct tcp_seq_hash6 tcp_seq_hash6[TSEQ_HASHSIZE];
+
+static const struct tok tcp_flag_values[] = {
+ { TH_FIN, "F" },
+ { TH_SYN, "S" },
+ { TH_RST, "R" },
+ { TH_PUSH, "P" },
+ { TH_ACK, "." },
+ { TH_URG, "U" },
+ { TH_ECNECHO, "E" },
+ { TH_CWR, "W" },
+ { 0, NULL }
+};
+
+static const struct tok tcp_option_values[] = {
+ { TCPOPT_EOL, "eol" },
+ { TCPOPT_NOP, "nop" },
+ { TCPOPT_MAXSEG, "mss" },
+ { TCPOPT_WSCALE, "wscale" },
+ { TCPOPT_SACKOK, "sackOK" },
+ { TCPOPT_SACK, "sack" },
+ { TCPOPT_ECHO, "echo" },
+ { TCPOPT_ECHOREPLY, "echoreply" },
+ { TCPOPT_TIMESTAMP, "TS" },
+ { TCPOPT_CC, "cc" },
+ { TCPOPT_CCNEW, "ccnew" },
+ { TCPOPT_CCECHO, "" },
+ { TCPOPT_SIGNATURE, "md5" },
+ { TCPOPT_SCPS, "scps" },
+ { TCPOPT_UTO, "uto" },
+ { TCPOPT_TCPAO, "tcp-ao" },
+ { TCPOPT_MPTCP, "mptcp" },
+ { TCPOPT_FASTOPEN, "tfo" },
+ { TCPOPT_EXPERIMENT2, "exp" },
+ { 0, NULL }
+};
+
+static uint16_t
+tcp_cksum(netdissect_options *ndo,
+ const struct ip *ip,
+ const struct tcphdr *tp,
+ u_int len)
+{
+ return nextproto4_cksum(ndo, ip, (const uint8_t *)tp, len, len,
+ IPPROTO_TCP);
+}
+
+static uint16_t
+tcp6_cksum(netdissect_options *ndo,
+ const struct ip6_hdr *ip6,
+ const struct tcphdr *tp,
+ u_int len)
+{
+ return nextproto6_cksum(ndo, ip6, (const uint8_t *)tp, len, len,
+ IPPROTO_TCP);
+}
+
+void
+tcp_print(netdissect_options *ndo,
+ const u_char *bp, u_int length,
+ const u_char *bp2, int fragmented)
+{
+ const struct tcphdr *tp;
+ const struct ip *ip;
+ u_char flags;
+ u_int hlen;
+ char ch;
+ uint16_t sport, dport, win, urp;
+ uint32_t seq, ack, thseq, thack;
+ u_int utoval;
+ uint16_t magic;
+ int rev;
+ const struct ip6_hdr *ip6;
+ u_int header_len; /* Header length in bytes */
+
+ ndo->ndo_protocol = "tcp";
+ tp = (const struct tcphdr *)bp;
+ ip = (const struct ip *)bp2;
+ if (IP_V(ip) == 6)
+ ip6 = (const struct ip6_hdr *)bp2;
+ else
+ ip6 = NULL;
+ ch = '\0';
+ if (!ND_TTEST_2(tp->th_dport)) {
+ if (ip6) {
+ ND_PRINT("%s > %s:",
+ GET_IP6ADDR_STRING(ip6->ip6_src),
+ GET_IP6ADDR_STRING(ip6->ip6_dst));
+ } else {
+ ND_PRINT("%s > %s:",
+ GET_IPADDR_STRING(ip->ip_src),
+ GET_IPADDR_STRING(ip->ip_dst));
+ }
+ nd_print_trunc(ndo);
+ return;
+ }
+
+ sport = GET_BE_U_2(tp->th_sport);
+ dport = GET_BE_U_2(tp->th_dport);
+
+ if (ip6) {
+ if (GET_U_1(ip6->ip6_nxt) == IPPROTO_TCP) {
+ ND_PRINT("%s.%s > %s.%s: ",
+ GET_IP6ADDR_STRING(ip6->ip6_src),
+ tcpport_string(ndo, sport),
+ GET_IP6ADDR_STRING(ip6->ip6_dst),
+ tcpport_string(ndo, dport));
+ } else {
+ ND_PRINT("%s > %s: ",
+ tcpport_string(ndo, sport), tcpport_string(ndo, dport));
+ }
+ } else {
+ if (GET_U_1(ip->ip_p) == IPPROTO_TCP) {
+ ND_PRINT("%s.%s > %s.%s: ",
+ GET_IPADDR_STRING(ip->ip_src),
+ tcpport_string(ndo, sport),
+ GET_IPADDR_STRING(ip->ip_dst),
+ tcpport_string(ndo, dport));
+ } else {
+ ND_PRINT("%s > %s: ",
+ tcpport_string(ndo, sport), tcpport_string(ndo, dport));
+ }
+ }
+
+ ND_TCHECK_SIZE(tp);
+
+ hlen = TH_OFF(tp) * 4;
+
+ if (hlen < sizeof(*tp)) {
+ ND_PRINT(" tcp %u [bad hdr length %u - too short, < %zu]",
+ length - hlen, hlen, sizeof(*tp));
+ return;
+ }
+
+ seq = GET_BE_U_4(tp->th_seq);
+ ack = GET_BE_U_4(tp->th_ack);
+ win = GET_BE_U_2(tp->th_win);
+ urp = GET_BE_U_2(tp->th_urp);
+
+ if (ndo->ndo_qflag) {
+ ND_PRINT("tcp %u", length - hlen);
+ if (hlen > length) {
+ ND_PRINT(" [bad hdr length %u - too long, > %u]",
+ hlen, length);
+ }
+ return;
+ }
+
+ flags = GET_U_1(tp->th_flags);
+ ND_PRINT("Flags [%s]", bittok2str_nosep(tcp_flag_values, "none", flags));
+
+ if (!ndo->ndo_Sflag && (flags & TH_ACK)) {
+ /*
+ * Find (or record) the initial sequence numbers for
+ * this conversation. (we pick an arbitrary
+ * collating order so there's only one entry for
+ * both directions).
+ */
+ rev = 0;
+ if (ip6) {
+ struct tcp_seq_hash6 *th;
+ struct tcp_seq_hash6 *tcp_seq_hash;
+ const void *src, *dst;
+ struct tha6 tha;
+
+ tcp_seq_hash = tcp_seq_hash6;
+ src = (const void *)ip6->ip6_src;
+ dst = (const void *)ip6->ip6_dst;
+ if (sport > dport)
+ rev = 1;
+ else if (sport == dport) {
+ if (UNALIGNED_MEMCMP(src, dst, sizeof(ip6->ip6_dst)) > 0)
+ rev = 1;
+ }
+ if (rev) {
+ UNALIGNED_MEMCPY(&tha.src, dst, sizeof(ip6->ip6_dst));
+ UNALIGNED_MEMCPY(&tha.dst, src, sizeof(ip6->ip6_src));
+ tha.port = ((u_int)dport) << 16 | sport;
+ } else {
+ UNALIGNED_MEMCPY(&tha.dst, dst, sizeof(ip6->ip6_dst));
+ UNALIGNED_MEMCPY(&tha.src, src, sizeof(ip6->ip6_src));
+ tha.port = ((u_int)sport) << 16 | dport;
+ }
+
+ for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
+ th->nxt; th = th->nxt)
+ if (memcmp((char *)&tha, (char *)&th->addr,
+ sizeof(th->addr)) == 0)
+ break;
+
+ if (!th->nxt || (flags & TH_SYN)) {
+ /* didn't find it or new conversation */
+ /* calloc() return used by the 'tcp_seq_hash6'
+ hash table: do not free() */
+ if (th->nxt == NULL) {
+ th->nxt = (struct tcp_seq_hash6 *)
+ calloc(1, sizeof(*th));
+ if (th->nxt == NULL)
+ (*ndo->ndo_error)(ndo,
+ S_ERR_ND_MEM_ALLOC,
+ "%s: calloc", __func__);
+ }
+ th->addr = tha;
+ if (rev)
+ th->ack = seq, th->seq = ack - 1;
+ else
+ th->seq = seq, th->ack = ack - 1;
+ } else {
+ if (rev)
+ seq -= th->ack, ack -= th->seq;
+ else
+ seq -= th->seq, ack -= th->ack;
+ }
+
+ thseq = th->seq;
+ thack = th->ack;
+ } else {
+ struct tcp_seq_hash *th;
+ struct tcp_seq_hash *tcp_seq_hash;
+ struct tha tha;
+
+ tcp_seq_hash = tcp_seq_hash4;
+ if (sport > dport)
+ rev = 1;
+ else if (sport == dport) {
+ if (UNALIGNED_MEMCMP(ip->ip_src, ip->ip_dst, sizeof(ip->ip_dst)) > 0)
+ rev = 1;
+ }
+ if (rev) {
+ UNALIGNED_MEMCPY(&tha.src, ip->ip_dst,
+ sizeof(ip->ip_dst));
+ UNALIGNED_MEMCPY(&tha.dst, ip->ip_src,
+ sizeof(ip->ip_src));
+ tha.port = ((u_int)dport) << 16 | sport;
+ } else {
+ UNALIGNED_MEMCPY(&tha.dst, ip->ip_dst,
+ sizeof(ip->ip_dst));
+ UNALIGNED_MEMCPY(&tha.src, ip->ip_src,
+ sizeof(ip->ip_src));
+ tha.port = ((u_int)sport) << 16 | dport;
+ }
+
+ for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
+ th->nxt; th = th->nxt)
+ if (memcmp((char *)&tha, (char *)&th->addr,
+ sizeof(th->addr)) == 0)
+ break;
+
+ if (!th->nxt || (flags & TH_SYN)) {
+ /* didn't find it or new conversation */
+ /* calloc() return used by the 'tcp_seq_hash4'
+ hash table: do not free() */
+ if (th->nxt == NULL) {
+ th->nxt = (struct tcp_seq_hash *)
+ calloc(1, sizeof(*th));
+ if (th->nxt == NULL)
+ (*ndo->ndo_error)(ndo,
+ S_ERR_ND_MEM_ALLOC,
+ "%s: calloc", __func__);
+ }
+ th->addr = tha;
+ if (rev)
+ th->ack = seq, th->seq = ack - 1;
+ else
+ th->seq = seq, th->ack = ack - 1;
+ } else {
+ if (rev)
+ seq -= th->ack, ack -= th->seq;
+ else
+ seq -= th->seq, ack -= th->ack;
+ }
+
+ thseq = th->seq;
+ thack = th->ack;
+ }
+ } else {
+ /*fool gcc*/
+ thseq = thack = rev = 0;
+ }
+ if (hlen > length) {
+ ND_PRINT(" [bad hdr length %u - too long, > %u]",
+ hlen, length);
+ return;
+ }
+
+ if (ndo->ndo_vflag && !ndo->ndo_Kflag && !fragmented) {
+ /* Check the checksum, if possible. */
+ uint16_t sum, tcp_sum;
+
+ if (IP_V(ip) == 4) {
+ if (ND_TTEST_LEN(tp->th_sport, length)) {
+ sum = tcp_cksum(ndo, ip, tp, length);
+ tcp_sum = GET_BE_U_2(tp->th_sum);
+
+ ND_PRINT(", cksum 0x%04x", tcp_sum);
+ if (sum != 0)
+ ND_PRINT(" (incorrect -> 0x%04x)",
+ in_cksum_shouldbe(tcp_sum, sum));
+ else
+ ND_PRINT(" (correct)");
+ }
+ } else if (IP_V(ip) == 6) {
+ if (ND_TTEST_LEN(tp->th_sport, length)) {
+ sum = tcp6_cksum(ndo, ip6, tp, length);
+ tcp_sum = GET_BE_U_2(tp->th_sum);
+
+ ND_PRINT(", cksum 0x%04x", tcp_sum);
+ if (sum != 0)
+ ND_PRINT(" (incorrect -> 0x%04x)",
+ in_cksum_shouldbe(tcp_sum, sum));
+ else
+ ND_PRINT(" (correct)");
+
+ }
+ }
+ }
+
+ length -= hlen;
+ if (ndo->ndo_vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {
+ ND_PRINT(", seq %u", seq);
+
+ if (length > 0) {
+ ND_PRINT(":%u", seq + length);
+ }
+ }
+
+ if (flags & TH_ACK) {
+ ND_PRINT(", ack %u", ack);
+ }
+
+ ND_PRINT(", win %u", win);
+
+ if (flags & TH_URG)
+ ND_PRINT(", urg %u", urp);
+ /*
+ * Handle any options.
+ */
+ if (hlen > sizeof(*tp)) {
+ const u_char *cp;
+ u_int i, opt, datalen;
+ u_int len;
+
+ hlen -= sizeof(*tp);
+ cp = (const u_char *)tp + sizeof(*tp);
+ ND_PRINT(", options [");
+ while (hlen > 0) {
+ if (ch != '\0')
+ ND_PRINT("%c", ch);
+ opt = GET_U_1(cp);
+ cp++;
+ if (ZEROLENOPT(opt))
+ len = 1;
+ else {
+ len = GET_U_1(cp);
+ cp++; /* total including type, len */
+ if (len < 2 || len > hlen)
+ goto bad;
+ --hlen; /* account for length byte */
+ }
+ --hlen; /* account for type byte */
+ datalen = 0;
+
+/* Bail if "l" bytes of data are not left or were not captured */
+#define LENCHECK(l) { if ((l) > hlen) goto bad; ND_TCHECK_LEN(cp, l); }
+
+
+ ND_PRINT("%s", tok2str(tcp_option_values, "unknown-%u", opt));
+
+ switch (opt) {
+
+ case TCPOPT_MAXSEG:
+ datalen = 2;
+ LENCHECK(datalen);
+ ND_PRINT(" %u", GET_BE_U_2(cp));
+ break;
+
+ case TCPOPT_WSCALE:
+ datalen = 1;
+ LENCHECK(datalen);
+ ND_PRINT(" %u", GET_U_1(cp));
+ break;
+
+ case TCPOPT_SACK:
+ datalen = len - 2;
+ if (datalen % 8 != 0) {
+ ND_PRINT(" invalid sack");
+ } else {
+ uint32_t s, e;
+
+ ND_PRINT(" %u ", datalen / 8);
+ for (i = 0; i < datalen; i += 8) {
+ LENCHECK(i + 4);
+ s = GET_BE_U_4(cp + i);
+ LENCHECK(i + 8);
+ e = GET_BE_U_4(cp + i + 4);
+ if (rev) {
+ s -= thseq;
+ e -= thseq;
+ } else {
+ s -= thack;
+ e -= thack;
+ }
+ ND_PRINT("{%u:%u}", s, e);
+ }
+ }
+ break;
+
+ case TCPOPT_CC:
+ case TCPOPT_CCNEW:
+ case TCPOPT_CCECHO:
+ case TCPOPT_ECHO:
+ case TCPOPT_ECHOREPLY:
+
+ /*
+ * those options share their semantics.
+ * fall through
+ */
+ datalen = 4;
+ LENCHECK(datalen);
+ ND_PRINT(" %u", GET_BE_U_4(cp));
+ break;
+
+ case TCPOPT_TIMESTAMP:
+ datalen = 8;
+ LENCHECK(datalen);
+ ND_PRINT(" val %u ecr %u",
+ GET_BE_U_4(cp),
+ GET_BE_U_4(cp + 4));
+ break;
+
+ case TCPOPT_SIGNATURE:
+ datalen = TCP_SIGLEN;
+ LENCHECK(datalen);
+ ND_PRINT(" ");
+#ifdef HAVE_LIBCRYPTO
+ switch (tcp_verify_signature(ndo, ip, tp,
+ bp + TH_OFF(tp) * 4, length, cp)) {
+
+ case SIGNATURE_VALID:
+ ND_PRINT("valid");
+ break;
+
+ case SIGNATURE_INVALID:
+ nd_print_invalid(ndo);
+ break;
+
+ case CANT_CHECK_SIGNATURE:
+ ND_PRINT("can't check - ");
+ for (i = 0; i < TCP_SIGLEN; ++i)
+ ND_PRINT("%02x",
+ GET_U_1(cp + i));
+ break;
+ }
+#else
+ for (i = 0; i < TCP_SIGLEN; ++i)
+ ND_PRINT("%02x", GET_U_1(cp + i));
+#endif
+ break;
+
+ case TCPOPT_SCPS:
+ datalen = 2;
+ LENCHECK(datalen);
+ ND_PRINT(" cap %02x id %u", GET_U_1(cp),
+ GET_U_1(cp + 1));
+ break;
+
+ case TCPOPT_TCPAO:
+ datalen = len - 2;
+ /* RFC 5925 Section 2.2:
+ * "The Length value MUST be greater than or equal to 4."
+ * (This includes the Kind and Length fields already processed
+ * at this point.)
+ */
+ if (datalen < 2) {
+ nd_print_invalid(ndo);
+ } else {
+ LENCHECK(1);
+ ND_PRINT(" keyid %u", GET_U_1(cp));
+ LENCHECK(2);
+ ND_PRINT(" rnextkeyid %u",
+ GET_U_1(cp + 1));
+ if (datalen > 2) {
+ ND_PRINT(" mac 0x");
+ for (i = 2; i < datalen; i++) {
+ LENCHECK(i + 1);
+ ND_PRINT("%02x",
+ GET_U_1(cp + i));
+ }
+ }
+ }
+ break;
+
+ case TCPOPT_EOL:
+ case TCPOPT_NOP:
+ case TCPOPT_SACKOK:
+ /*
+ * Nothing interesting.
+ * fall through
+ */
+ break;
+
+ case TCPOPT_UTO:
+ datalen = 2;
+ LENCHECK(datalen);
+ utoval = GET_BE_U_2(cp);
+ ND_PRINT(" 0x%x", utoval);
+ if (utoval & 0x0001)
+ utoval = (utoval >> 1) * 60;
+ else
+ utoval >>= 1;
+ ND_PRINT(" %u", utoval);
+ break;
+
+ case TCPOPT_MPTCP:
+ {
+ const u_char *snapend_save;
+ int ret;
+
+ datalen = len - 2;
+ LENCHECK(datalen);
+ /* Update the snapend to the end of the option
+ * before calling mptcp_print(). Some options
+ * (MPTCP or others) may be present after a
+ * MPTCP option. This prevents that, in
+ * mptcp_print(), the remaining length < the
+ * remaining caplen.
+ */
+ snapend_save = ndo->ndo_snapend;
+ ndo->ndo_snapend = ND_MIN(cp - 2 + len,
+ ndo->ndo_snapend);
+ ret = mptcp_print(ndo, cp - 2, len, flags);
+ ndo->ndo_snapend = snapend_save;
+ if (!ret)
+ goto bad;
+ break;
+ }
+
+ case TCPOPT_FASTOPEN:
+ datalen = len - 2;
+ LENCHECK(datalen);
+ ND_PRINT(" ");
+ print_tcp_fastopen_option(ndo, cp, datalen, FALSE);
+ break;
+
+ case TCPOPT_EXPERIMENT2:
+ datalen = len - 2;
+ LENCHECK(datalen);
+ if (datalen < 2)
+ goto bad;
+ /* RFC6994 */
+ magic = GET_BE_U_2(cp);
+ ND_PRINT("-");
+
+ switch(magic) {
+
+ case 0xf989: /* TCP Fast Open RFC 7413 */
+ print_tcp_fastopen_option(ndo, cp + 2, datalen - 2, TRUE);
+ break;
+
+ default:
+ /* Unknown magic number */
+ ND_PRINT("%04x", magic);
+ break;
+ }
+ break;
+
+ default:
+ datalen = len - 2;
+ if (datalen)
+ ND_PRINT(" 0x");
+ for (i = 0; i < datalen; ++i) {
+ LENCHECK(i + 1);
+ ND_PRINT("%02x", GET_U_1(cp + i));
+ }
+ break;
+ }
+
+ /* Account for data printed */
+ cp += datalen;
+ hlen -= datalen;
+
+ /* Check specification against observed length */
+ ++datalen; /* option octet */
+ if (!ZEROLENOPT(opt))
+ ++datalen; /* size octet */
+ if (datalen != len)
+ ND_PRINT("[len %u]", len);
+ ch = ',';
+ if (opt == TCPOPT_EOL)
+ break;
+ }
+ ND_PRINT("]");
+ }
+
+ /*
+ * Print length field before crawling down the stack.
+ */
+ ND_PRINT(", length %u", length);
+
+ if (length == 0)
+ return;
+
+ /*
+ * Decode payload if necessary.
+ */
+ header_len = TH_OFF(tp) * 4;
+ /*
+ * Do a bounds check before decoding the payload.
+ * At least the header data is required.
+ */
+ if (!ND_TTEST_LEN(bp, header_len)) {
+ ND_PRINT(" [remaining caplen(%u) < header length(%u)]",
+ ND_BYTES_AVAILABLE_AFTER(bp), header_len);
+ nd_trunc_longjmp(ndo);
+ }
+ bp += header_len;
+ if ((flags & TH_RST) && ndo->ndo_vflag) {
+ print_tcp_rst_data(ndo, bp, length);
+ return;
+ }
+
+ if (ndo->ndo_packettype) {
+ switch (ndo->ndo_packettype) {
+ case PT_ZMTP1:
+ zmtp1_print(ndo, bp, length);
+ break;
+ case PT_RESP:
+ resp_print(ndo, bp, length);
+ break;
+ case PT_DOMAIN:
+ /* over_tcp: TRUE, is_mdns: FALSE */
+ domain_print(ndo, bp, length, TRUE, FALSE);
+ break;
+ }
+ return;
+ }
+
+ if (IS_SRC_OR_DST_PORT(TELNET_PORT)) {
+ telnet_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(SMTP_PORT)) {
+ ND_PRINT(": ");
+ smtp_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(WHOIS_PORT)) {
+ ND_PRINT(": ");
+ whois_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(BGP_PORT))
+ bgp_print(ndo, bp, length);
+ else if (IS_SRC_OR_DST_PORT(PPTP_PORT))
+ pptp_print(ndo, bp);
+ else if (IS_SRC_OR_DST_PORT(REDIS_PORT))
+ resp_print(ndo, bp, length);
+ else if (IS_SRC_OR_DST_PORT(SSH_PORT))
+ ssh_print(ndo, bp, length);
+#ifdef ENABLE_SMB
+ else if (IS_SRC_OR_DST_PORT(NETBIOS_SSN_PORT))
+ nbt_tcp_print(ndo, bp, length);
+ else if (IS_SRC_OR_DST_PORT(SMB_PORT))
+ smb_tcp_print(ndo, bp, length);
+#endif
+ else if (IS_SRC_OR_DST_PORT(BEEP_PORT))
+ beep_print(ndo, bp, length);
+ else if (IS_SRC_OR_DST_PORT(OPENFLOW_PORT_OLD) || IS_SRC_OR_DST_PORT(OPENFLOW_PORT_IANA))
+ openflow_print(ndo, bp, length);
+ else if (IS_SRC_OR_DST_PORT(FTP_PORT)) {
+ ND_PRINT(": ");
+ ftp_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(HTTP_PORT) || IS_SRC_OR_DST_PORT(HTTP_PORT_ALT)) {
+ ND_PRINT(": ");
+ http_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(RTSP_PORT) || IS_SRC_OR_DST_PORT(RTSP_PORT_ALT)) {
+ ND_PRINT(": ");
+ rtsp_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(NAMESERVER_PORT)) {
+ /* over_tcp: TRUE, is_mdns: FALSE */
+ domain_print(ndo, bp, length, TRUE, FALSE);
+ } else if (IS_SRC_OR_DST_PORT(MSDP_PORT)) {
+ msdp_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(RPKI_RTR_PORT)) {
+ rpki_rtr_print(ndo, bp, length);
+ } else if (IS_SRC_OR_DST_PORT(LDP_PORT)) {
+ ldp_print(ndo, bp, length);
+ } else if ((IS_SRC_OR_DST_PORT(NFS_PORT)) &&
+ length >= 4 && ND_TTEST_4(bp)) {
+ /*
+ * If data present, header length valid, and NFS port used,
+ * assume NFS.
+ * Pass offset of data plus 4 bytes for RPC TCP msg length
+ * to NFS print routines.
+ */
+ uint32_t fraglen;
+ const struct sunrpc_msg *rp;
+ enum sunrpc_msg_type direction;
+
+ fraglen = GET_BE_U_4(bp) & 0x7FFFFFFF;
+ if (fraglen > (length) - 4)
+ fraglen = (length) - 4;
+ rp = (const struct sunrpc_msg *)(bp + 4);
+ if (ND_TTEST_4(rp->rm_direction)) {
+ direction = (enum sunrpc_msg_type) GET_BE_U_4(rp->rm_direction);
+ if (dport == NFS_PORT && direction == SUNRPC_CALL) {
+ ND_PRINT(": NFS request xid %u ",
+ GET_BE_U_4(rp->rm_xid));
+ nfsreq_noaddr_print(ndo, (const u_char *)rp, fraglen, (const u_char *)ip);
+ return;
+ }
+ if (sport == NFS_PORT && direction == SUNRPC_REPLY) {
+ ND_PRINT(": NFS reply xid %u ",
+ GET_BE_U_4(rp->rm_xid));
+ nfsreply_noaddr_print(ndo, (const u_char *)rp, fraglen, (const u_char *)ip);
+ return;
+ }
+ }
+ }
+
+ return;
+bad:
+ ND_PRINT("[bad opt]");
+ if (ch != '\0')
+ ND_PRINT("]");
+ return;
+trunc:
+ nd_print_trunc(ndo);
+ if (ch != '\0')
+ ND_PRINT(">");
+}
+
+/*
+ * RFC1122 says the following on data in RST segments:
+ *
+ * 4.2.2.12 RST Segment: RFC-793 Section 3.4
+ *
+ * A TCP SHOULD allow a received RST segment to include data.
+ *
+ * DISCUSSION
+ * It has been suggested that a RST segment could contain
+ * ASCII text that encoded and explained the cause of the
+ * RST. No standard has yet been established for such
+ * data.
+ *
+ */
+
+static void
+print_tcp_rst_data(netdissect_options *ndo,
+ const u_char *sp, u_int length)
+{
+ u_char c;
+
+ ND_PRINT(ND_TTEST_LEN(sp, length) ? " [RST" : " [!RST");
+ if (length > MAX_RST_DATA_LEN) {
+ length = MAX_RST_DATA_LEN; /* can use -X for longer */
+ ND_PRINT("+"); /* indicate we truncate */
+ }
+ ND_PRINT(" ");
+ while (length && sp < ndo->ndo_snapend) {
+ c = GET_U_1(sp);
+ sp++;
+ fn_print_char(ndo, c);
+ length--;
+ }
+ ND_PRINT("]");
+}
+
+static void
+print_tcp_fastopen_option(netdissect_options *ndo, const u_char *cp,
+ u_int datalen, int exp)
+{
+ u_int i;
+
+ if (exp)
+ ND_PRINT("tfo");
+
+ if (datalen == 0) {
+ /* Fast Open Cookie Request */
+ ND_PRINT(" cookiereq");
+ } else {
+ /* Fast Open Cookie */
+ if (datalen % 2 != 0 || datalen < 4 || datalen > 16) {
+ nd_print_invalid(ndo);
+ } else {
+ ND_PRINT(" cookie ");
+ for (i = 0; i < datalen; ++i)
+ ND_PRINT("%02x", GET_U_1(cp + i));
+ }
+ }
+}
+
+#ifdef HAVE_LIBCRYPTO
+DIAG_OFF_DEPRECATION
+static int
+tcp_verify_signature(netdissect_options *ndo,
+ const struct ip *ip, const struct tcphdr *tp,
+ const u_char *data, u_int length, const u_char *rcvsig)
+{
+ struct tcphdr tp1;
+ u_char sig[TCP_SIGLEN];
+ char zero_proto = 0;
+ MD5_CTX ctx;
+ uint16_t savecsum, tlen;
+ const struct ip6_hdr *ip6;
+ uint32_t len32;
+ uint8_t nxt;
+
+ if (data + length > ndo->ndo_snapend) {
+ ND_PRINT("snaplen too short, ");
+ return (CANT_CHECK_SIGNATURE);
+ }
+
+ tp1 = *tp;
+
+ if (ndo->ndo_sigsecret == NULL) {
+ ND_PRINT("shared secret not supplied with -M, ");
+ return (CANT_CHECK_SIGNATURE);
+ }
+
+ MD5_Init(&ctx);
+ /*
+ * Step 1: Update MD5 hash with IP pseudo-header.
+ */
+ if (IP_V(ip) == 4) {
+ MD5_Update(&ctx, (const char *)&ip->ip_src, sizeof(ip->ip_src));
+ MD5_Update(&ctx, (const char *)&ip->ip_dst, sizeof(ip->ip_dst));
+ MD5_Update(&ctx, (const char *)&zero_proto, sizeof(zero_proto));
+ MD5_Update(&ctx, (const char *)&ip->ip_p, sizeof(ip->ip_p));
+ tlen = GET_BE_U_2(ip->ip_len) - IP_HL(ip) * 4;
+ tlen = htons(tlen);
+ MD5_Update(&ctx, (const char *)&tlen, sizeof(tlen));
+ } else if (IP_V(ip) == 6) {
+ ip6 = (const struct ip6_hdr *)ip;
+ MD5_Update(&ctx, (const char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
+ MD5_Update(&ctx, (const char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
+ len32 = htonl(GET_BE_U_2(ip6->ip6_plen));
+ MD5_Update(&ctx, (const char *)&len32, sizeof(len32));
+ nxt = 0;
+ MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+ MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+ MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+ nxt = IPPROTO_TCP;
+ MD5_Update(&ctx, (const char *)&nxt, sizeof(nxt));
+ } else {
+ ND_PRINT("IP version not 4 or 6, ");
+ return (CANT_CHECK_SIGNATURE);
+ }
+
+ /*
+ * Step 2: Update MD5 hash with TCP header, excluding options.
+ * The TCP checksum must be set to zero.
+ */
+ memcpy(&savecsum, tp1.th_sum, sizeof(savecsum));
+ memset(tp1.th_sum, 0, sizeof(tp1.th_sum));
+ MD5_Update(&ctx, (const char *)&tp1, sizeof(struct tcphdr));
+ memcpy(tp1.th_sum, &savecsum, sizeof(tp1.th_sum));
+ /*
+ * Step 3: Update MD5 hash with TCP segment data, if present.
+ */
+ if (length > 0)
+ MD5_Update(&ctx, data, length);
+ /*
+ * Step 4: Update MD5 hash with shared secret.
+ */
+ MD5_Update(&ctx, ndo->ndo_sigsecret, strlen(ndo->ndo_sigsecret));
+ MD5_Final(sig, &ctx);
+
+ if (memcmp(rcvsig, sig, TCP_SIGLEN) == 0)
+ return (SIGNATURE_VALID);
+ else
+ return (SIGNATURE_INVALID);
+}
+DIAG_ON_DEPRECATION
+#endif /* HAVE_LIBCRYPTO */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 08:40:27 +0000