diff options
Diffstat (limited to 'contrib/tcpdump/print-tcp.c')
| -rw-r--r-- | contrib/tcpdump/print-tcp.c | 295 |
1 files changed, 243 insertions, 52 deletions
diff --git a/contrib/tcpdump/print-tcp.c b/contrib/tcpdump/print-tcp.c index 451bab6..40d3f49 100644 --- a/contrib/tcpdump/print-tcp.c +++ b/contrib/tcpdump/print-tcp.c @@ -21,7 +21,7 @@ #ifndef lint static const char rcsid[] = - "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.63 1999/12/22 15:44:10 itojun Exp $ (LBL)"; + "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.81 2000/12/23 20:55:22 guy Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H @@ -31,28 +31,31 @@ static const char rcsid[] = #include <sys/param.h> #include <sys/time.h> +#include <rpc/rpc.h> + #include <netinet/in.h> -#include <netinet/in_systm.h> -#include <netinet/ip.h> -#include <netinet/ip_var.h> -#include <netinet/tcp.h> -#ifdef HAVE_MEMORY_H -#include <memory.h> -#endif #include <stdio.h> #include <stdlib.h> #include <string.h> +#include <ctype.h> #include <unistd.h> -#ifdef INET6 -#include <netinet/ip6.h> -#endif - #include "interface.h" #include "addrtoname.h" #include "extract.h" +#include "tcp.h" + +#include "ip.h" +#ifdef INET6 +#include "ip6.h" +#endif + +static void print_tcp_rst_data(register const u_char *sp, u_int length); + +#define MAX_RST_DATA_LEN 30 + /* Compatibility */ #ifndef TCPOPT_WSCALE #define TCPOPT_WSCALE 3 /* window scale factor (rfc1072) */ @@ -82,6 +85,17 @@ static const char rcsid[] = #define TCPOPT_CCECHO 13 /* T/TCP CC options (rfc1644) */ #endif +/* + * Definitions required for ECN + * for use if the OS running tcpdump does not have ECN + */ +#ifndef TH_ECNECHO +#define TH_ECNECHO 0x40 /* ECN Echo in tcp header */ +#endif +#ifndef TH_CWR +#define TH_CWR 0x80 /* ECN Cwnd Reduced in tcp header*/ +#endif + struct tha { #ifndef INET6 struct in_addr src; @@ -115,17 +129,114 @@ static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE]; #define BGP_PORT 179 #endif #define NETBIOS_SSN_PORT 139 +#define BXXP_PORT 10288 +#ifndef NFS_PORT +#define NFS_PORT 2049 +#endif + +static int tcp_cksum(register const struct ip *ip, + register const struct tcphdr *tp, + register int len) +{ + int i, tlen; + union phu { + struct phdr { + u_int32_t src; + u_int32_t dst; + u_char mbz; + u_char proto; + u_int16_t len; + } 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); + + /* pseudo-header.. */ + phu.ph.len = htons(tlen); + 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)); + + 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); +} + +#ifdef INET6 +static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp, + int len) +{ + int i, tlen; + register const u_int16_t *sp; + u_int32_t sum; + union { + struct { + struct in6_addr ph_src; + struct in6_addr ph_dst; + u_int32_t ph_len; + u_int8_t ph_zero[3]; + u_int8_t ph_nxt; + } ph; + 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_nxt = IPPROTO_TCP; + + sum = 0; + for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++) + sum += phu.pa[i]; + + 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); +} +#endif void tcp_print(register const u_char *bp, register u_int length, - register const u_char *bp2) + register const u_char *bp2, int fragmented) { register const struct tcphdr *tp; register const struct ip *ip; register u_char flags; register int hlen; register char ch; - u_short sport, dport, win, urp; + u_int16_t sport, dport, win, urp; u_int32_t seq, ack, thseq, thack; int threv; #ifdef INET6 @@ -135,7 +246,7 @@ tcp_print(register const u_char *bp, register u_int length, tp = (struct tcphdr *)bp; ip = (struct ip *)bp2; #ifdef INET6 - if (ip->ip_v == 6) + if (IP_V(ip) == 6) ip6 = (struct ip6_hdr *)bp2; else ip6 = NULL; @@ -151,6 +262,28 @@ tcp_print(register const u_char *bp, register u_int length, sport = ntohs(tp->th_sport); dport = ntohs(tp->th_dport); + + hlen = TH_OFF(tp) * 4; + + /* + * If data present 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 ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend && + dport == NFS_PORT) { + nfsreq_print((u_char *)tp + hlen + 4, length-hlen, + (u_char *)ip); + return; + } else if ((u_char *)tp + 4 + sizeof(struct rpc_msg) + <= snapend && + sport == NFS_PORT) { + nfsreply_print((u_char *)tp + hlen + 4,length-hlen, + (u_char *)ip); + return; + } + } #ifdef INET6 if (ip6) { if (ip6->ip6_nxt == IPPROTO_TCP) { @@ -180,21 +313,17 @@ tcp_print(register const u_char *bp, register u_int length, TCHECK(*tp); - seq = ntohl(tp->th_seq); - ack = ntohl(tp->th_ack); + 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); if (qflag) { - (void)printf("tcp %d", length - tp->th_off * 4); + (void)printf("tcp %d", length - TH_OFF(tp) * 4); return; } -#ifdef TH_ECN - if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH|TH_ECN)) -#else - if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH)) -#endif - { + if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH| + TH_ECNECHO|TH_CWR)) { if (flags & TH_SYN) putchar('S'); if (flags & TH_FIN) @@ -203,22 +332,13 @@ tcp_print(register const u_char *bp, register u_int length, putchar('R'); if (flags & TH_PUSH) putchar('P'); -#ifdef TH_ECN - if (flags & TH_ECN) - putchar('C'); -#endif + if (flags & TH_CWR) + putchar('W'); /* congestion _W_indow reduced (ECN) */ + if (flags & TH_ECNECHO) + putchar('E'); /* ecn _E_cho sent (ECN) */ } else putchar('.'); - if (flags&0xc0) { - printf(" ["); - if (flags&0x40) - printf("ECN-Echo"); - if (flags&0x80) - printf("%sCWR", (flags&0x40) ? "," : ""); - printf("]"); - } - if (!Sflag && (flags & TH_ACK)) { register struct tcp_seq_hash *th; register int rev; @@ -230,7 +350,7 @@ tcp_print(register const u_char *bp, register u_int length, * both directions). */ #ifdef INET6 - bzero(&tha, sizeof(tha)); + memset(&tha, 0, sizeof(tha)); rev = 0; if (ip6) { if (sport > dport) { @@ -292,7 +412,7 @@ tcp_print(register const u_char *bp, register u_int length, sizeof(th->addr))) break; - if (!th->nxt || flags & TH_SYN) { + if (!th->nxt || (flags & TH_SYN)) { /* didn't find it or new conversation */ if (th->nxt == NULL) { th->nxt = (struct tcp_seq_hash *) @@ -305,22 +425,48 @@ tcp_print(register const u_char *bp, register u_int length, th->ack = seq, th->seq = ack - 1; else th->seq = seq, th->ack = ack - 1; - } else { - - thseq = th->seq; - thack = th->ack; + } 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 = threv = 0; } - hlen = tp->th_off * 4; if (hlen > length) { (void)printf(" [bad hdr length]"); return; } + + if (IP_V(ip) == 4 && vflag && !fragmented) { + int sum; + if (TTEST2(tp->th_sport, length)) { + sum = tcp_cksum(ip, tp, length); + if (sum != 0) + (void)printf(" [bad tcp cksum %x!]", sum); + else + (void)printf(" [tcp sum ok]"); + } + } +#ifdef INET6 + if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !fragmented) { + int sum; + if (TTEST2(tp->th_sport, length)) { + sum = tcp6_cksum(ip6, tp, length); + if (sum != 0) + (void)printf(" [bad tcp cksum %x!]", sum); + else + (void)printf(" [tcp sum ok]"); + } + } +#endif + length -= hlen; if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) (void)printf(" %u:%u(%d)", seq, seq + length, length); @@ -493,14 +639,21 @@ tcp_print(register const u_char *bp, register u_int length, /* * Decode payload if necessary. */ - bp += (tp->th_off * 4); - if (!qflag && vflag && length > 0 - && (sport == TELNET_PORT || dport == TELNET_PORT)) - telnet_print(bp, length); - else if (sport == BGP_PORT || dport == BGP_PORT) - bgp_print(bp, length); - else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT) - nbt_tcp_print(bp, length); + bp += TH_OFF(tp) * 4; + if (flags & TH_RST) { + if (vflag) + print_tcp_rst_data(bp, length); + } else { + if (sport == TELNET_PORT || dport == TELNET_PORT) { + if (!qflag && vflag) + telnet_print(bp, length); + } else if (sport == BGP_PORT || dport == BGP_PORT) + bgp_print(bp, length); + 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); + } return; bad: fputs("[bad opt]", stdout); @@ -513,3 +666,41 @@ trunc: putchar('>'); } +/* + * 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(register const u_char *sp, u_int length) +{ + int c; + + if (TTEST2(*sp, length)) + printf(" [RST"); + else + printf(" [!RST"); + if (length > MAX_RST_DATA_LEN) { + length = MAX_RST_DATA_LEN; /* can use -X for longer */ + putchar('+'); /* indicate we truncate */ + } + putchar(' '); + while (length-- && sp <= snapend) { + c = *sp++; + if (isprint(c)) + putchar(c); + else + putchar('.'); + } + putchar(']'); +} |
