X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/5de6f0fd81f60ec31d9cfceafd1001d59fbfb376..refs/heads/tcpdump-3.8:/print-tcp.c diff --git a/print-tcp.c b/print-tcp.c index eecf0b48..9a965ff4 100644 --- a/print-tcp.c +++ b/print-tcp.c @@ -20,26 +20,21 @@ */ #ifndef lint -static const char rcsid[] = - "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.86 2001-05-09 01:16:57 fenner Exp $ (LBL)"; +static const char rcsid[] _U_ = + "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.107.2.5 2004-07-28 20:11:31 guy Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include -#include +#include #include -#include - #include #include #include -#include -#include #include "interface.h" #include "addrtoname.h" @@ -51,6 +46,7 @@ static const char rcsid[] = #ifdef INET6 #include "ip6.h" #endif +#include "ipproto.h" #include "nameser.h" @@ -95,16 +91,17 @@ static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE]; #ifndef PPTP_PORT #define PPTP_PORT 1723 #endif -#define BXXP_PORT 10288 +#define BEEP_PORT 10288 #ifndef NFS_PORT #define NFS_PORT 2049 #endif +#define MSDP_PORT 639 +#define LDP_PORT 646 static int tcp_cksum(register const struct ip *ip, register const struct tcphdr *tp, - register int len) + register u_int len) { - int i, tlen; union phu { struct phdr { u_int32_t src; @@ -115,41 +112,28 @@ static int tcp_cksum(register const struct ip *ip, } ph; u_int16_t pa[6]; } phu; - register const u_int16_t *sp; - u_int32_t sum; - tlen = ntohs(ip->ip_len) - ((const char *)tp-(const char*)ip); + const u_int16_t *sp; /* pseudo-header.. */ - phu.ph.len = htons(tlen); + 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)); - memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t)); + if (IP_HL(ip) == 5) + memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t)); + else + phu.ph.dst = ip_finddst(ip); sp = &phu.pa[0]; - sum = sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5]; - - sp = (const u_int16_t *)tp; - - for (i=0; i<(tlen&~1); i+= 2) - sum += *sp++; - - if (tlen & 1) { - sum += htons( (*(const u_int8_t *)sp) << 8); - } - - while (sum > 0xffff) - sum = (sum & 0xffff) + (sum >> 16); - sum = ~sum & 0xffff; - - return (sum); + return in_cksum((u_short *)tp, len, + sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5]); } #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 { @@ -163,14 +147,11 @@ static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp, 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; @@ -179,10 +160,10 @@ static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp, 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) @@ -200,7 +181,7 @@ tcp_print(register const u_char *bp, register u_int length, register const struct tcphdr *tp; register const struct ip *ip; register u_char flags; - register int hlen; + register u_int hlen; register char ch; u_int16_t sport, dport, win, urp; u_int32_t seq, ack, thseq, thack; @@ -225,18 +206,18 @@ tcp_print(register const u_char *bp, register u_int length, 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; /* - * If data present and NFS port used, assume NFS. + * 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. */ - if (!qflag) { + if (!qflag && hlen >= sizeof(*tp) && hlen <= length) { if ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend && dport == NFS_PORT) { nfsreq_print((u_char *)tp + hlen + 4, length - hlen, @@ -245,7 +226,7 @@ tcp_print(register const u_char *bp, register u_int length, } else if ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend && sport == NFS_PORT) { - nfsreply_print((u_char *)tp + hlen + 4,length-hlen, + nfsreply_print((u_char *)tp + hlen + 4, length - hlen, (u_char *)ip); return; } @@ -277,15 +258,25 @@ tcp_print(register const u_char *bp, register u_int length, } } + if (hlen < sizeof(*tp)) { + (void)printf(" tcp %d [bad hdr length %u - too short, < %lu]", + length - hlen, hlen, (unsigned long)sizeof(*tp)); + return; + } + 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); + (void)printf("tcp %d", length - hlen); + if (hlen > length) { + (void)printf(" [bad hdr length %u - too long, > %u]", + hlen, length); + } return; } if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH| @@ -307,6 +298,7 @@ tcp_print(register const u_char *bp, register u_int length, if (!Sflag && (flags & TH_ACK)) { register struct tcp_seq_hash *th; + const void *src, *dst; register int rev; struct tha tha; /* @@ -319,63 +311,68 @@ tcp_print(register const u_char *bp, register u_int length, 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)) { @@ -405,17 +402,20 @@ tcp_print(register const u_char *bp, register u_int length, thseq = thack = threv = 0; } if (hlen > length) { - (void)printf(" [bad hdr length]"); + (void)printf(" [bad hdr length %u - too long, > %u]", + hlen, length); return; } if (IP_V(ip) == 4 && vflag && !fragmented) { - int sum; + u_int16_t sum, tcp_sum; if (TTEST2(tp->th_sport, length)) { sum = tcp_cksum(ip, tp, length); - if (sum != 0) - (void)printf(" [bad tcp cksum %x!]", sum); - else + if (sum != 0) { + 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(" [tcp sum ok]"); } } @@ -434,7 +434,7 @@ tcp_print(register const u_char *bp, register u_int length, length -= hlen; if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) - (void)printf(" %u:%u(%d)", seq, seq + length, length); + (void)printf(" %u:%u(%u)", seq, seq + length, length); if (flags & TH_ACK) (void)printf(" ack %u", ack); @@ -445,10 +445,12 @@ tcp_print(register const u_char *bp, register u_int length, /* * Handle any options. */ - if ((hlen -= sizeof(*tp)) > 0) { + if (hlen > sizeof(*tp)) { register const u_char *cp; - register int i, opt, len, datalen; + register u_int i, opt, datalen; + register u_int len; + hlen -= sizeof(*tp); cp = (const u_char *)tp + sizeof(*tp); putchar(' '); ch = '<'; @@ -572,7 +574,7 @@ tcp_print(register const u_char *bp, register u_int length, break; default: - (void)printf("opt-%d:", opt); + (void)printf("opt-%u:", opt); datalen = len - 2; for (i = 0; i < datalen; ++i) { LENCHECK(i); @@ -615,16 +617,26 @@ tcp_print(register const u_char *bp, register u_int length, } else if (sport == BGP_PORT || dport == BGP_PORT) bgp_print(bp, length); else if (sport == PPTP_PORT || dport == PPTP_PORT) - pptp_print(bp, length); + pptp_print(bp); +#ifdef TCPDUMP_DO_SMB else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT) nbt_tcp_print(bp, length); - else if (sport == BXXP_PORT || dport == BXXP_PORT) - bxxp_print(bp, length); +#endif + else if (sport == BEEP_PORT || dport == BEEP_PORT) + beep_print(bp, length); else if (length > 2 && - (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT)) { - /* TCP DNS query has 2byte length at the head */ - ns_print(bp + 2, length - 2); + (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT || + sport == MULTICASTDNS_PORT || dport == MULTICASTDNS_PORT)) { + /* + * TCP DNS query has 2byte length at the head. + * XXX packet could be unaligned, it can go strange + */ + ns_print(bp + 2, length - 2, 0); + } else if (sport == MSDP_PORT || dport == MSDP_PORT) { + msdp_print(bp, length); } + else if (sport == LDP_PORT || dport == LDP_PORT) + printf(": LDP, length: %u", length); } return; bad: