1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1993
5 * The Regents of the University of California.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)tcp_debug.c 8.1 (Berkeley) 6/10/93
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37
38 #include "opt_inet.h"
39 #include "opt_inet6.h"
40 #include "opt_tcpdebug.h"
41
42 #ifdef TCPDEBUG
43 /* load symbolic names */
44 #define PRUREQUESTS
45 #define TCPSTATES
46 #define TCPTIMERS
47 #define TANAMES
48 #endif
49
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/kernel.h>
53 #include <sys/lock.h>
54 #include <sys/mbuf.h>
55 #include <sys/mutex.h>
56 #include <sys/protosw.h>
57 #include <sys/socket.h>
58
59 #include <netinet/in.h>
60 #include <netinet/in_systm.h>
61 #include <netinet/ip.h>
62 #ifdef INET6
63 #include <netinet/ip6.h>
64 #endif
65 #include <netinet/ip_var.h>
66 #include <netinet/tcp.h>
67 #include <netinet/tcp_fsm.h>
68 #include <netinet/tcp_timer.h>
69 #include <netinet/tcp_var.h>
70 #include <netinet/tcpip.h>
71 #include <netinet/tcp_debug.h>
72
73 #ifdef TCPDEBUG
74 static int tcpconsdebug = 0;
75 #endif
76
77 /*
78 * Global ring buffer of TCP debugging state. Each entry captures a snapshot
79 * of TCP connection state at any given moment. tcp_debx addresses at the
80 * next available slot. There is no explicit export of this data structure;
81 * it will be read via /dev/kmem by debugging tools.
82 */
83 static struct tcp_debug tcp_debug[TCP_NDEBUG];
84 static int tcp_debx;
85
86 /*
87 * All global state is protected by tcp_debug_mtx; tcp_trace() is split into
88 * two parts, one of which saves connection and other state into the global
89 * array (locked by tcp_debug_mtx).
90 */
91 struct mtx tcp_debug_mtx;
92 MTX_SYSINIT(tcp_debug_mtx, &tcp_debug_mtx, "tcp_debug_mtx", MTX_DEF);
93
94 /*
95 * Save TCP state at a given moment; optionally, both tcpcb and TCP packet
96 * header state will be saved.
97 */
98 void
tcp_trace(short act,short ostate,struct tcpcb * tp,void * ipgen,struct tcphdr * th,int req)99 tcp_trace(short act, short ostate, struct tcpcb *tp, void *ipgen,
100 struct tcphdr *th, int req)
101 {
102 #ifdef INET6
103 int isipv6;
104 #endif /* INET6 */
105 tcp_seq seq, ack;
106 int len, flags;
107 struct tcp_debug *td;
108
109 mtx_lock(&tcp_debug_mtx);
110 td = &tcp_debug[tcp_debx++];
111 if (tcp_debx == TCP_NDEBUG)
112 tcp_debx = 0;
113 bzero(td, sizeof(*td));
114 #ifdef INET6
115 isipv6 = (ipgen != NULL && ((struct ip *)ipgen)->ip_v == 6) ? 1 : 0;
116 #endif /* INET6 */
117 td->td_family =
118 #ifdef INET6
119 (isipv6 != 0) ? AF_INET6 :
120 #endif
121 AF_INET;
122 #ifdef INET
123 td->td_time = iptime();
124 #endif
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 #ifdef INET
133 case AF_INET:
134 bcopy(ipgen, &td->td_ti.ti_i, sizeof(td->td_ti.ti_i));
135 break;
136 #endif
137 #ifdef INET6
138 case AF_INET6:
139 bcopy(ipgen, td->td_ip6buf, sizeof(td->td_ip6buf));
140 break;
141 #endif
142 }
143 }
144 if (th != NULL) {
145 switch (td->td_family) {
146 #ifdef INET
147 case AF_INET:
148 td->td_ti.ti_t = *th;
149 break;
150 #endif
151 #ifdef INET6
152 case AF_INET6:
153 td->td_ti6.th = *th;
154 break;
155 #endif
156 }
157 }
158 td->td_req = req;
159 mtx_unlock(&tcp_debug_mtx);
160 #ifdef TCPDEBUG
161 if (tcpconsdebug == 0)
162 return;
163 if (tp != NULL)
164 printf("%p %s:", tp, tcpstates[ostate]);
165 else
166 printf("???????? ");
167 printf("%s ", tanames[act]);
168 switch (act) {
169 case TA_INPUT:
170 case TA_OUTPUT:
171 case TA_DROP:
172 if (ipgen == NULL || th == NULL)
173 break;
174 seq = th->th_seq;
175 ack = th->th_ack;
176 len =
177 #ifdef INET6
178 isipv6 ? ntohs(((struct ip6_hdr *)ipgen)->ip6_plen) :
179 #endif
180 ntohs(((struct ip *)ipgen)->ip_len);
181 if (act == TA_OUTPUT) {
182 seq = ntohl(seq);
183 ack = ntohl(ack);
184 }
185 if (act == TA_OUTPUT)
186 len -= sizeof (struct tcphdr);
187 if (len)
188 printf("[%x..%x)", seq, seq+len);
189 else
190 printf("%x", seq);
191 printf("@%x, urp=%x", ack, th->th_urp);
192 flags = th->th_flags;
193 if (flags) {
194 char *cp = "<";
195 #define pf(f) { \
196 if (th->th_flags & TH_##f) { \
197 printf("%s%s", cp, #f); \
198 cp = ","; \
199 } \
200 }
201 pf(SYN); pf(ACK); pf(FIN); pf(RST); pf(PUSH); pf(URG);
202 printf(">");
203 }
204 break;
205
206 case TA_USER:
207 printf("%s", prurequests[req&0xff]);
208 if ((req & 0xff) == PRU_SLOWTIMO)
209 printf("<%s>", tcptimers[req>>8]);
210 break;
211 }
212 if (tp != NULL)
213 printf(" -> %s", tcpstates[tp->t_state]);
214 /* print out internal state of tp !?! */
215 printf("\n");
216 if (tp == NULL)
217 return;
218 printf(
219 "\trcv_(nxt,wnd,up) (%lx,%lx,%lx) snd_(una,nxt,max) (%lx,%lx,%lx)\n",
220 (u_long)tp->rcv_nxt, (u_long)tp->rcv_wnd, (u_long)tp->rcv_up,
221 (u_long)tp->snd_una, (u_long)tp->snd_nxt, (u_long)tp->snd_max);
222 printf("\tsnd_(wl1,wl2,wnd) (%lx,%lx,%lx)\n",
223 (u_long)tp->snd_wl1, (u_long)tp->snd_wl2, (u_long)tp->snd_wnd);
224 #endif /* TCPDEBUG */
225 }
226