*/
#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.103 2002-09-05 21:25:49 guy Exp $ (LBL)";
+static const char rcsid[] _U_ =
+ "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.112 2004-04-05 00:12:54 mcr Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#ifdef INET6
#include "ip6.h"
#endif
+#include "ipproto.h"
#include "nameser.h"
+#ifdef HAVE_LIBCRYPTO
+#include <openssl/md5.h>
+
+static int tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
+ const u_char *data, int length, const u_char *rcvsig);
+#endif
+
static void print_tcp_rst_data(register const u_char *sp, u_int length);
#define MAX_RST_DATA_LEN 30
static int tcp_cksum(register const struct ip *ip,
register const struct tcphdr *tp,
- register int len)
+ register u_int len)
{
union phu {
struct phdr {
const u_int16_t *sp;
/* pseudo-header.. */
- phu.ph.len = htons(len); /* XXX */
+ phu.ph.len = htons((u_int16_t)len);
phu.ph.mbz = 0;
phu.ph.proto = IPPROTO_TCP;
memcpy(&phu.ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t));
#ifdef INET6
static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
- int len)
+ u_int len)
{
- int i, tlen;
+ size_t i;
register const u_int16_t *sp;
u_int32_t sum;
union {
u_int16_t pa[20];
} phu;
- tlen = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr) -
- ((const char *)tp - (const char*)ip6);
-
/* pseudo-header */
memset(&phu, 0, sizeof(phu));
phu.ph.ph_src = ip6->ip6_src;
phu.ph.ph_dst = ip6->ip6_dst;
- phu.ph.ph_len = htonl(tlen);
+ phu.ph.ph_len = htonl(len);
phu.ph.ph_nxt = IPPROTO_TCP;
sum = 0;
sp = (const u_int16_t *)tp;
- for (i = 0; i < (tlen & ~1); i += 2)
+ for (i = 0; i < (len & ~1); i += 2)
sum += *sp++;
- if (tlen & 1)
+ if (len & 1)
sum += htons((*(const u_int8_t *)sp) << 8);
while (sum > 0xffff)
return;
}
- sport = ntohs(tp->th_sport);
- dport = ntohs(tp->th_dport);
+ sport = EXTRACT_16BITS(&tp->th_sport);
+ dport = EXTRACT_16BITS(&tp->th_dport);
hlen = TH_OFF(tp) * 4;
TCHECK(*tp);
- seq = (u_int32_t)ntohl(tp->th_seq);
- ack = (u_int32_t)ntohl(tp->th_ack);
- win = ntohs(tp->th_win);
- urp = ntohs(tp->th_urp);
+ seq = EXTRACT_32BITS(&tp->th_seq);
+ ack = EXTRACT_32BITS(&tp->th_ack);
+ win = EXTRACT_16BITS(&tp->th_win);
+ urp = EXTRACT_16BITS(&tp->th_urp);
if (qflag) {
(void)printf("tcp %d", length - TH_OFF(tp) * 4);
if (!Sflag && (flags & TH_ACK)) {
register struct tcp_seq_hash *th;
+ const void *src, *dst;
register int rev;
struct tha tha;
/*
memset(&tha, 0, sizeof(tha));
rev = 0;
if (ip6) {
+ src = &ip6->ip6_src;
+ dst = &ip6->ip6_dst;
if (sport > dport)
rev = 1;
else if (sport == dport) {
- int i;
-
- for (i = 0; i < 4; i++) {
- if (((u_int32_t *)(&ip6->ip6_src))[i] >
- ((u_int32_t *)(&ip6->ip6_dst))[i]) {
- rev = 1;
- break;
- }
- }
+ if (memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
+ rev = 1;
}
if (rev) {
- tha.src = ip6->ip6_dst;
- tha.dst = ip6->ip6_src;
+ memcpy(&tha.src, dst, sizeof ip6->ip6_dst);
+ memcpy(&tha.dst, src, sizeof ip6->ip6_src);
tha.port = dport << 16 | sport;
} else {
- tha.dst = ip6->ip6_dst;
- tha.src = ip6->ip6_src;
+ memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
+ memcpy(&tha.src, src, sizeof ip6->ip6_src);
tha.port = sport << 16 | dport;
}
} else {
- if (sport > dport ||
- (sport == dport &&
- ip->ip_src.s_addr > ip->ip_dst.s_addr)) {
+ src = &ip->ip_src;
+ dst = &ip->ip_dst;
+ if (sport > dport)
rev = 1;
+ else if (sport == dport) {
+ if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
+ rev = 1;
}
if (rev) {
- *(struct in_addr *)&tha.src = ip->ip_dst;
- *(struct in_addr *)&tha.dst = ip->ip_src;
+ memcpy(&tha.src, dst, sizeof ip->ip_dst);
+ memcpy(&tha.dst, src, sizeof ip->ip_src);
tha.port = dport << 16 | sport;
} else {
- *(struct in_addr *)&tha.dst = ip->ip_dst;
- *(struct in_addr *)&tha.src = ip->ip_src;
+ memcpy(&tha.dst, dst, sizeof ip->ip_dst);
+ memcpy(&tha.src, src, sizeof ip->ip_src);
tha.port = sport << 16 | dport;
}
}
#else
- if (sport < dport ||
- (sport == dport &&
- ip->ip_src.s_addr < ip->ip_dst.s_addr)) {
- tha.src = ip->ip_src, tha.dst = ip->ip_dst;
- tha.port = sport << 16 | dport;
- rev = 0;
- } else {
- tha.src = ip->ip_dst, tha.dst = ip->ip_src;
- tha.port = dport << 16 | sport;
+ rev = 0;
+ src = &ip->ip_src;
+ dst = &ip->ip_dst;
+ if (sport > dport)
rev = 1;
+ else if (sport == dport) {
+ if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
+ rev = 1;
+ }
+ if (rev) {
+ memcpy(&tha.src, dst, sizeof ip->ip_dst);
+ memcpy(&tha.dst, src, sizeof ip->ip_src);
+ tha.port = dport << 16 | sport;
+ } else {
+ memcpy(&tha.dst, dst, sizeof ip->ip_dst);
+ memcpy(&tha.src, src, sizeof ip->ip_src);
+ tha.port = sport << 16 | dport;
}
#endif
threv = rev;
for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
th->nxt; th = th->nxt)
- if (!memcmp((char *)&tha, (char *)&th->addr,
- sizeof(th->addr)))
+ if (memcmp((char *)&tha, (char *)&th->addr,
+ sizeof(th->addr)) == 0)
break;
if (!th->nxt || (flags & TH_SYN)) {
if (TTEST2(tp->th_sport, length)) {
sum = tcp_cksum(ip, tp, length);
if (sum != 0) {
- tcp_sum = ntohs(tp->th_sum);
+ tcp_sum = EXTRACT_16BITS(&tp->th_sum);
(void)printf(" [bad tcp cksum %x (->%x)!]",
tcp_sum, in_cksum_shouldbe(tcp_sum, sum));
} else
(void)printf(" %u", EXTRACT_32BITS(cp));
break;
+ case TCPOPT_SIGNATURE:
+ (void)printf("md5:");
+ if (IP_V(ip) != 4) {
+ (void)printf("!ipv4");
+ break;
+ }
+ datalen = TCP_SIGLEN;
+ LENCHECK(datalen);
+#ifdef HAVE_LIBCRYPTO
+ if (tcp_verify_signature(ip, tp,
+ bp + TH_OFF(tp) * 4, length, cp) == 0)
+ (void)printf("valid");
+ else
+ (void)printf("invalid");
+#else
+ for (i = 0; i < TCP_SIGLEN; ++i)
+ (void)printf("%02x", cp[i]);
+#endif
+ break;
+
default:
(void)printf("opt-%u:", opt);
datalen = len - 2;
* TCP DNS query has 2byte length at the head.
* XXX packet could be unaligned, it can go strange
*/
- ns_print(bp + 2, length - 2);
+ ns_print(bp + 2, length - 2, 0);
} else if (sport == MSDP_PORT || dport == MSDP_PORT) {
msdp_print(bp, length);
}
}
putchar(']');
}
+
+#ifdef HAVE_LIBCRYPTO
+static int
+tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
+ const u_char *data, int length, const u_char *rcvsig)
+{
+ struct tcphdr tp1;
+ char sig[TCP_SIGLEN];
+ char zero_proto = 0;
+ MD5_CTX ctx;
+ u_short savecsum, tlen;
+
+ tp1 = *tp;
+
+ if (tcpmd5secret == NULL)
+ return (-1);
+
+ MD5_Init(&ctx);
+ /*
+ * Step 1: Update MD5 hash with IP pseudo-header.
+ */
+ MD5_Update(&ctx, (char *)&ip->ip_src, sizeof(ip->ip_src));
+ MD5_Update(&ctx, (char *)&ip->ip_dst, sizeof(ip->ip_dst));
+ MD5_Update(&ctx, (char *)&zero_proto, sizeof(zero_proto));
+ MD5_Update(&ctx, (char *)&ip->ip_p, sizeof(ip->ip_p));
+ tlen = EXTRACT_16BITS(&ip->ip_len) - IP_HL(ip) * 4;
+ tlen = htons(tlen);
+ MD5_Update(&ctx, (char *)&tlen, sizeof(tlen));
+
+ /*
+ * Step 2: Update MD5 hash with TCP header, excluding options.
+ * The TCP checksum must be set to zero.
+ */
+ savecsum = tp1.th_sum;
+ tp1.th_sum = 0;
+ MD5_Update(&ctx, (char *)&tp1, sizeof(struct tcphdr));
+ tp1.th_sum = savecsum;
+ /*
+ * 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, tcpmd5secret, strlen(tcpmd5secret));
+ MD5_Final(sig, &ctx);
+
+ return (memcmp(rcvsig, sig, 16));
+}
+#endif /* HAVE_LIBCRYPTO */
projects / tcpdump / blobdiff