aboutsummaryrefslogtreecommitdiff
path: root/sys/netinet/tcp_debug.c
blob: aedaa131095f27e09055c742f8079bd4c8b99ef9 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1993
 *	The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)tcp_debug.c	8.1 (Berkeley) 6/10/93
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_tcpdebug.h"

#ifdef TCPDEBUG
/* load symbolic names */
#define PRUREQUESTS
#define TCPSTATES
#define	TCPTIMERS
#define	TANAMES
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/protosw.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#ifdef INET6
#include <netinet/ip6.h>
#endif
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/tcpip.h>
#include <netinet/tcp_debug.h>

#ifdef TCPDEBUG
static int		tcpconsdebug = 0;
#endif

/*
 * Global ring buffer of TCP debugging state.  Each entry captures a snapshot
 * of TCP connection state at any given moment.  tcp_debx addresses at the
 * next available slot.  There is no explicit export of this data structure;
 * it will be read via /dev/kmem by debugging tools.
 */
static struct tcp_debug	tcp_debug[TCP_NDEBUG];
static int		tcp_debx;

/*
 * All global state is protected by tcp_debug_mtx; tcp_trace() is split into
 * two parts, one of which saves connection and other state into the global
 * array (locked by tcp_debug_mtx).
 */
struct mtx		tcp_debug_mtx;
MTX_SYSINIT(tcp_debug_mtx, &tcp_debug_mtx, "tcp_debug_mtx", MTX_DEF);

/*
 * Save TCP state at a given moment; optionally, both tcpcb and TCP packet
 * header state will be saved.
 */
void
tcp_trace(short act, short ostate, struct tcpcb *tp, void *ipgen,
    struct tcphdr *th, int req)
{
#ifdef INET6
	int isipv6;
#endif /* INET6 */
	tcp_seq seq, ack;
	int len, flags;
	struct tcp_debug *td;

	mtx_lock(&tcp_debug_mtx);
	td = &tcp_debug[tcp_debx++];
	if (tcp_debx == TCP_NDEBUG)
		tcp_debx = 0;
	bzero(td, sizeof(*td));
#ifdef INET6
	isipv6 = (ipgen != NULL && ((struct ip *)ipgen)->ip_v == 6) ? 1 : 0;
#endif /* INET6 */
	td->td_family =
#ifdef INET6
	    (isipv6 != 0) ? AF_INET6 :
#endif
	    AF_INET;
#ifdef INET
	td->td_time = iptime();
#endif
	td->td_act = act;
	td->td_ostate = ostate;
	td->td_tcb = (caddr_t)tp;
	if (tp != NULL)
		td->td_cb = *tp;
	if (ipgen != NULL) {
		switch (td->td_family) {
#ifdef INET
		case AF_INET:
			bcopy(ipgen, &td->td_ti.ti_i, sizeof(td->td_ti.ti_i));
			break;
#endif
#ifdef INET6
		case AF_INET6:
			bcopy(ipgen, td->td_ip6buf, sizeof(td->td_ip6buf));
			break;
#endif
		}
	}
	if (th != NULL) {
		switch (td->td_family) {
#ifdef INET
		case AF_INET:
			td->td_ti.ti_t = *th;
			break;
#endif
#ifdef INET6
		case AF_INET6:
			td->td_ti6.th = *th;
			break;
#endif
		}
	}
	td->td_req = req;
	mtx_unlock(&tcp_debug_mtx);
#ifdef TCPDEBUG
	if (tcpconsdebug == 0)
		return;
	if (tp != NULL)
		printf("%p %s:", tp, tcpstates[ostate]);
	else
		printf("???????? ");
	printf("%s ", tanames[act]);
	switch (act) {
	case TA_INPUT:
	case TA_OUTPUT:
	case TA_DROP:
		if (ipgen == NULL || th == NULL)
			break;
		seq = th->th_seq;
		ack = th->th_ack;
		len =
#ifdef INET6
		    isipv6 ? ntohs(((struct ip6_hdr *)ipgen)->ip6_plen) :
#endif
		    ntohs(((struct ip *)ipgen)->ip_len);
		if (act == TA_OUTPUT) {
			seq = ntohl(seq);
			ack = ntohl(ack);
		}
		if (act == TA_OUTPUT)
			len -= sizeof (struct tcphdr);
		if (len)
			printf("[%x..%x)", seq, seq+len);
		else
			printf("%x", seq);
		printf("@%x, urp=%x", ack, th->th_urp);
		flags = th->th_flags;
		if (flags) {
			char *cp = "<";
#define pf(f) {					\
	if (th->th_flags & TH_##f) {		\
		printf("%s%s", cp, #f);		\
		cp = ",";			\
	}					\
}
			pf(SYN); pf(ACK); pf(FIN); pf(RST); pf(PUSH); pf(URG);
			printf(">");
		}
		break;

	case TA_USER:
		printf("%s", prurequests[req&0xff]);
		if ((req & 0xff) == PRU_SLOWTIMO)
			printf("<%s>", tcptimers[req>>8]);
		break;
	}
	if (tp != NULL)
		printf(" -> %s", tcpstates[tp->t_state]);
	/* print out internal state of tp !?! */
	printf("\n");
	if (tp == NULL)
		return;
	printf(
	"\trcv_(nxt,wnd,up) (%lx,%lx,%lx) snd_(una,nxt,max) (%lx,%lx,%lx)\n",
	    (u_long)tp->rcv_nxt, (u_long)tp->rcv_wnd, (u_long)tp->rcv_up,
	    (u_long)tp->snd_una, (u_long)tp->snd_nxt, (u_long)tp->snd_max);
	printf("\tsnd_(wl1,wl2,wnd) (%lx,%lx,%lx)\n",
	    (u_long)tp->snd_wl1, (u_long)tp->snd_wl2, (u_long)tp->snd_wnd);
#endif /* TCPDEBUG */
}