tcp_debug.c revision 182855
1/*- 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 4. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * @(#)tcp_debug.c 8.1 (Berkeley) 6/10/93 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/sys/netinet/tcp_debug.c 182855 2008-09-07 20:44:45Z bz $"); 35 36#include "opt_inet.h" 37#include "opt_inet6.h" 38#include "opt_tcpdebug.h" 39 40#ifndef INET 41#error The option TCPDEBUG requires option INET. 42#endif 43 44#ifdef TCPDEBUG 45/* load symbolic names */ 46#define PRUREQUESTS 47#define TCPSTATES 48#define TCPTIMERS 49#define TANAMES 50#endif 51 52#include <sys/param.h> 53#include <sys/systm.h> 54#include <sys/kernel.h> 55#include <sys/lock.h> 56#include <sys/mbuf.h> 57#include <sys/mutex.h> 58#include <sys/protosw.h> 59#include <sys/socket.h> 60 61#include <netinet/in.h> 62#include <netinet/in_systm.h> 63#include <netinet/ip.h> 64#ifdef INET6 65#include <netinet/ip6.h> 66#endif 67#include <netinet/ip_var.h> 68#include <netinet/tcp.h> 69#include <netinet/tcp_fsm.h> 70#include <netinet/tcp_timer.h> 71#include <netinet/tcp_var.h> 72#include <netinet/tcpip.h> 73#include <netinet/tcp_debug.h> 74 75#ifdef TCPDEBUG 76static int tcpconsdebug = 0; 77#endif 78 79/* 80 * Global ring buffer of TCP debugging state. Each entry captures a snapshot 81 * of TCP connection state at any given moment. tcp_debx addresses at the 82 * next available slot. There is no explicit export of this data structure; 83 * it will be read via /dev/kmem by debugging tools. 84 */ 85static struct tcp_debug tcp_debug[TCP_NDEBUG]; 86static int tcp_debx; 87 88/* 89 * All global state is protected by tcp_debug_mtx; tcp_trace() is split into 90 * two parts, one of which saves connection and other state into the global 91 * array (locked by tcp_debug_mtx). 92 */ 93struct mtx tcp_debug_mtx; 94MTX_SYSINIT(tcp_debug_mtx, &tcp_debug_mtx, "tcp_debug_mtx", MTX_DEF); 95 96/* 97 * Save TCP state at a given moment; optionally, both tcpcb and TCP packet 98 * header state will be saved. 99 */ 100void 101tcp_trace(short act, short ostate, struct tcpcb *tp, void *ipgen, 102 struct tcphdr *th, int req) 103{ 104#ifdef INET6 105 int isipv6; 106#endif /* INET6 */ 107 tcp_seq seq, ack; 108 int len, flags; 109 struct tcp_debug *td; 110 111 mtx_lock(&tcp_debug_mtx); 112 td = &tcp_debug[tcp_debx++]; 113 if (tcp_debx == TCP_NDEBUG) 114 tcp_debx = 0; 115 bzero(td, sizeof(*td)); 116#ifdef INET6 117 isipv6 = (ipgen != NULL && ((struct ip *)ipgen)->ip_v == 6) ? 1 : 0; 118#endif /* INET6 */ 119 td->td_family = 120#ifdef INET6 121 (isipv6 != 0) ? AF_INET6 : 122#endif 123 AF_INET; 124 td->td_time = iptime(); 125 td->td_act = act; 126 td->td_ostate = ostate; 127 td->td_tcb = (caddr_t)tp; 128 if (tp != NULL) 129 td->td_cb = *tp; 130 if (ipgen != NULL) { 131 switch (td->td_family) { 132 case AF_INET: 133 bcopy(ipgen, &td->td_ti.ti_i, sizeof(td->td_ti.ti_i)); 134 break; 135#ifdef INET6 136 case AF_INET6: 137 bcopy(ipgen, td->td_ip6buf, sizeof(td->td_ip6buf)); 138 break; 139#endif 140 } 141 } 142 if (th != NULL) { 143 switch (td->td_family) { 144 case AF_INET: 145 td->td_ti.ti_t = *th; 146 break; 147#ifdef INET6 148 case AF_INET6: 149 td->td_ti6.th = *th; 150 break; 151#endif 152 } 153 } 154 td->td_req = req; 155 mtx_unlock(&tcp_debug_mtx); 156#ifdef TCPDEBUG 157 if (tcpconsdebug == 0) 158 return; 159 if (tp != NULL) 160 printf("%p %s:", tp, tcpstates[ostate]); 161 else 162 printf("???????? "); 163 printf("%s ", tanames[act]); 164 switch (act) { 165 case TA_INPUT: 166 case TA_OUTPUT: 167 case TA_DROP: 168 if (ipgen == NULL || th == NULL) 169 break; 170 seq = th->th_seq; 171 ack = th->th_ack; 172 len = 173#ifdef INET6 174 isipv6 ? ntohs(((struct ip6_hdr *)ipgen)->ip6_plen) : 175#endif 176 ((struct ip *)ipgen)->ip_len; 177 if (act == TA_OUTPUT) { 178 seq = ntohl(seq); 179 ack = ntohl(ack); 180 len = ntohs((u_short)len); 181 } 182 if (act == TA_OUTPUT) 183 len -= sizeof (struct tcphdr); 184 if (len) 185 printf("[%x..%x)", seq, seq+len); 186 else 187 printf("%x", seq); 188 printf("@%x, urp=%x", ack, th->th_urp); 189 flags = th->th_flags; 190 if (flags) { 191 char *cp = "<"; 192#define pf(f) { \ 193 if (th->th_flags & TH_##f) { \ 194 printf("%s%s", cp, #f); \ 195 cp = ","; \ 196 } \ 197} 198 pf(SYN); pf(ACK); pf(FIN); pf(RST); pf(PUSH); pf(URG); 199 printf(">"); 200 } 201 break; 202 203 case TA_USER: 204 printf("%s", prurequests[req&0xff]); 205 if ((req & 0xff) == PRU_SLOWTIMO) 206 printf("<%s>", tcptimers[req>>8]); 207 break; 208 } 209 if (tp != NULL) 210 printf(" -> %s", tcpstates[tp->t_state]); 211 /* print out internal state of tp !?! */ 212 printf("\n"); 213 if (tp == NULL) 214 return; 215 printf( 216 "\trcv_(nxt,wnd,up) (%lx,%lx,%lx) snd_(una,nxt,max) (%lx,%lx,%lx)\n", 217 (u_long)tp->rcv_nxt, tp->rcv_wnd, (u_long)tp->rcv_up, 218 (u_long)tp->snd_una, (u_long)tp->snd_nxt, (u_long)tp->snd_max); 219 printf("\tsnd_(wl1,wl2,wnd) (%lx,%lx,%lx)\n", 220 (u_long)tp->snd_wl1, (u_long)tp->snd_wl2, tp->snd_wnd); 221#endif /* TCPDEBUG */ 222} 223