xref: /freebsd/usr.bin/systat/netstat.c (revision fa4d25f5b4573a54eebeb7f254b52153b8d3811e) 
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 
34 __FBSDID("$FreeBSD$");
35 
36 #ifdef lint
37 static const char sccsid[] = "@(#)netstat.c	8.1 (Berkeley) 6/6/93";
38 #endif
39 
40 /*
41  * netstat
42  */
43 #include <sys/param.h>
44 #include <sys/queue.h>
45 #include <sys/socket.h>
46 #include <sys/callout.h>
47 #define	_WANT_SOCKET
48 #include <sys/socketvar.h>
49 #include <sys/protosw.h>
50 
51 #include <netinet/in.h>
52 #include <arpa/inet.h>
53 #include <net/route.h>
54 #include <netinet/in_systm.h>
55 #include <netinet/ip.h>
56 #ifdef INET6
57 #include <netinet/ip6.h>
58 #endif
59 #define	_WANT_INPCB
60 #include <netinet/in_pcb.h>
61 #include <netinet/ip_icmp.h>
62 #include <netinet/icmp_var.h>
63 #include <netinet/ip_var.h>
64 #include <netinet/tcp.h>
65 #include <netinet/tcpip.h>
66 #include <netinet/tcp_seq.h>
67 #define TCPSTATES
68 #include <netinet/tcp_fsm.h>
69 #include <netinet/tcp_timer.h>
70 #define	_WANT_TCPCB
71 #include <netinet/tcp_var.h>
72 #include <netinet/tcp_debug.h>
73 #include <netinet/udp.h>
74 #include <netinet/udp_var.h>
75 
76 #include <netdb.h>
77 #include <nlist.h>
78 #include <paths.h>
79 #include <stdlib.h>
80 #include <string.h>
81 
82 #include "systat.h"
83 #include "extern.h"
84 
85 static struct netinfo *enter(struct in_conninfo *, uint8_t, int, const char *);
86 static void enter_kvm(struct inpcb *, struct socket *, int, const char *);
87 static void enter_sysctl(struct xinpcb *, struct xsocket *, int, const char *);
88 static void fetchnetstat_kvm(void);
89 static void fetchnetstat_sysctl(void);
90 static char *inetname(struct sockaddr *);
91 static void inetprint(struct sockaddr *, const char *);
92 
93 #define	streq(a,b)	(strcmp(a,b)==0)
94 #define	YMAX(w)		(getmaxy(w)-2)
95 
96 WINDOW *
97 opennetstat(void)
98 {
99 	sethostent(1);
100 	setnetent(1);
101 	return (subwin(stdscr, LINES-3-1, 0, MAINWIN_ROW, 0));
102 }
103 
104 struct netinfo {
105 	TAILQ_ENTRY(netinfo) chain;
106 	short	ni_line;		/* line on screen */
107 	short	ni_seen;		/* 0 when not present in list */
108 	short	ni_flags;
109 #define	NIF_LACHG	0x1		/* local address changed */
110 #define	NIF_FACHG	0x2		/* foreign address changed */
111 	short	ni_state;		/* tcp state */
112 	const char	*ni_proto;		/* protocol */
113 	struct sockaddr_storage ni_lsa;	/* local address */
114 	struct sockaddr_storage	ni_fsa;	/* foreign address */
115 	u_int	ni_rcvcc;		/* rcv buffer character count */
116 	u_int	ni_sndcc;		/* snd buffer character count */
117 };
118 
119 static TAILQ_HEAD(netinfohead, netinfo) netcb = TAILQ_HEAD_INITIALIZER(netcb);
120 
121 static	int aflag = 0;
122 static	int nflag = 0;
123 static	int lastrow = 1;
124 
125 void
126 closenetstat(WINDOW *w)
127 {
128 	struct netinfo *p;
129 
130 	endhostent();
131 	endnetent();
132 	TAILQ_FOREACH(p, &netcb, chain) {
133 		if (p->ni_line != -1)
134 			lastrow--;
135 		p->ni_line = -1;
136 	}
137 	if (w != NULL) {
138 		wclear(w);
139 		wrefresh(w);
140 		delwin(w);
141 	}
142 }
143 
144 static const char *miblist[] = {
145 	"net.inet.tcp.pcblist",
146 	"net.inet.udp.pcblist"
147 };
148 
149 static char tcb[] = "tcb", udb[] = "udb";
150 
151 struct nlist namelist[] = {
152 #define	X_TCB	0
153 	{ .n_name = tcb },
154 #define	X_UDB	1
155 	{ .n_name = udb },
156 	{ .n_name = NULL },
157 };
158 
159 int
160 initnetstat(void)
161 {
162 	protos = TCP|UDP;
163 	return(1);
164 }
165 
166 void
167 fetchnetstat(void)
168 {
169 	if (use_kvm)
170 		fetchnetstat_kvm();
171 	else
172 		fetchnetstat_sysctl();
173 }
174 
175 static void
176 fetchnetstat_kvm(void)
177 {
178 	struct inpcb *next;
179 	struct netinfo *p;
180 	struct inpcbhead head;
181 	struct inpcb inpcb;
182 	struct socket sockb;
183 	struct tcpcb tcpcb;
184 	void *off;
185 	int istcp;
186 
187 	if (namelist[X_TCB].n_value == 0)
188 		return;
189 	TAILQ_FOREACH(p, &netcb, chain)
190 		p->ni_seen = 0;
191 	if (protos&TCP) {
192 		off = NPTR(X_TCB);
193 		istcp = 1;
194 	}
195 	else if (protos&UDP) {
196 		off = NPTR(X_UDB);
197 		istcp = 0;
198 	}
199 	else {
200 		error("No protocols to display");
201 		return;
202 	}
203 again:
204 	KREAD(off, &head, sizeof (struct inpcbhead));
205 	LIST_FOREACH(next, &head, inp_list) {
206 		KREAD(next, &inpcb, sizeof (inpcb));
207 		next = &inpcb;
208 		if (!aflag) {
209 			if (inpcb.inp_vflag & INP_IPV4) {
210 				if (inpcb.inp_laddr.s_addr == INADDR_ANY)
211 					continue;
212 			}
213 #ifdef INET6
214 			else if (inpcb.inp_vflag & INP_IPV6) {
215 				if (memcmp(&inpcb.in6p_laddr,
216 				    &in6addr_any, sizeof(in6addr_any)) == 0)
217 					continue;
218 			}
219 #endif
220 		}
221 		if (nhosts && !checkhost(&inpcb.inp_inc))
222 			continue;
223 		if (nports && !checkport(&inpcb.inp_inc))
224 			continue;
225 		if (istcp) {
226 			KREAD(inpcb.inp_socket, &sockb, sizeof (sockb));
227 			KREAD(inpcb.inp_ppcb, &tcpcb, sizeof (tcpcb));
228 			enter_kvm(&inpcb, &sockb, tcpcb.t_state, "tcp");
229 		} else
230 			enter_kvm(&inpcb, &sockb, 0, "udp");
231 	}
232 	if (istcp && (protos&UDP)) {
233 		istcp = 0;
234 		off = NPTR(X_UDB);
235 		goto again;
236 	}
237 }
238 
239 static void
240 fetchnetstat_sysctl(void)
241 {
242 	struct netinfo *p;
243 	int idx;
244 	struct xinpgen *inpg;
245 	char *cur, *end;
246 	struct xinpcb *xip = NULL;
247 	struct xtcpcb *xtp = NULL;
248 	int plen;
249 	size_t lsz;
250 
251 	TAILQ_FOREACH(p, &netcb, chain)
252 		p->ni_seen = 0;
253 	if (protos&TCP) {
254 		idx = 0;
255 	} else if (protos&UDP) {
256 		idx = 1;
257 	} else {
258 		error("No protocols to display");
259 		return;
260 	}
261 
262 	for (;idx < 2; idx++) {
263 		if (idx == 1 && !(protos&UDP))
264 			break;
265 		inpg = (struct xinpgen *)sysctl_dynread(miblist[idx], &lsz);
266 		if (inpg == NULL) {
267 			error("sysctl(%s...) failed", miblist[idx]);
268 			continue;
269 		}
270 		/*
271 		 * We currently do no require a consistent pcb list.
272 		 * Try to be robust in case of struct size changes
273 		 */
274 		cur = ((char *)inpg) + inpg->xig_len;
275 		/* There is also a trailing struct xinpgen */
276 		end = ((char *)inpg) + lsz - inpg->xig_len;
277 		if (end <= cur) {
278 			free(inpg);
279 			continue;
280 		}
281 		if (idx == 0) { /* TCP */
282 			xtp = (struct xtcpcb *)cur;
283 			plen = xtp->xt_len;
284 		} else {
285 			xip = (struct xinpcb *)cur;
286 			plen = xip->xi_len;
287 		}
288 		while (cur + plen <= end) {
289 			if (idx == 0) { /* TCP */
290 				xtp = (struct xtcpcb *)cur;
291 				xip = &xtp->xt_inp;
292 			} else {
293 				xip = (struct xinpcb *)cur;
294 			}
295 			cur += plen;
296 
297 			if (!aflag) {
298 				if (xip->inp_vflag & INP_IPV4) {
299 					if (xip->inp_laddr.s_addr == INADDR_ANY)
300 						continue;
301 				}
302 #ifdef INET6
303 				else if (xip->inp_vflag & INP_IPV6) {
304 					if (memcmp(&xip->in6p_laddr,
305 					    &in6addr_any, sizeof(in6addr_any))
306 					    == 0)
307 						continue;
308 				}
309 #endif
310 			}
311 			if (nhosts && !checkhost(&xip->inp_inc))
312 				continue;
313 			if (nports && !checkport(&xip->inp_inc))
314 				continue;
315 			if (idx == 0)
316 				enter_sysctl(xip, &xip->xi_socket,
317 				    xtp->t_state, "tcp");
318 			else
319 				enter_sysctl(xip, &xip->xi_socket, 0, "udp");
320 		}
321 		free(inpg);
322 	}
323 }
324 
325 static void
326 enter_kvm(struct inpcb *inp, struct socket *so, int state, const char *proto)
327 {
328 	struct netinfo *p;
329 
330 	if ((p = enter(&inp->inp_inc, inp->inp_vflag, state, proto)) != NULL) {
331 		p->ni_rcvcc = so->so_rcv.sb_ccc;
332 		p->ni_sndcc = so->so_snd.sb_ccc;
333 	}
334 }
335 
336 static void
337 enter_sysctl(struct xinpcb *xip, struct xsocket *so, int state,
338     const char *proto)
339 {
340 	struct netinfo *p;
341 
342 	if ((p = enter(&xip->inp_inc, xip->inp_vflag, state, proto)) != NULL) {
343 		p->ni_rcvcc = so->so_rcv.sb_cc;
344 		p->ni_sndcc = so->so_snd.sb_cc;
345 	}
346 }
347 
348 static struct netinfo *
349 enter(struct in_conninfo *inc, uint8_t vflag, int state, const char *proto)
350 {
351 	struct netinfo *p;
352 	struct sockaddr_storage lsa, fsa;
353 	struct sockaddr_in *sa4;
354 #ifdef INET6
355 	struct sockaddr_in6 *sa6;
356 #endif
357 
358 	memset(&lsa, 0, sizeof(lsa));
359 	memset(&fsa, 0, sizeof(fsa));
360 	if (vflag & INP_IPV4) {
361 		sa4 = (struct sockaddr_in *)&lsa;
362 		sa4->sin_addr = inc->inc_laddr;
363 		sa4->sin_port = inc->inc_lport;
364 		sa4->sin_family = AF_INET;
365 		sa4->sin_len = sizeof(struct sockaddr_in);
366 
367 		sa4 = (struct sockaddr_in *)&fsa;
368 		sa4->sin_addr = inc->inc_faddr;
369 		sa4->sin_port = inc->inc_fport;
370 		sa4->sin_family = AF_INET;
371 		sa4->sin_len = sizeof(struct sockaddr_in);
372 	}
373 #ifdef INET6
374 	else if (vflag & INP_IPV6) {
375 		sa6 = (struct sockaddr_in6 *)&lsa;
376 		memcpy(&sa6->sin6_addr, &inc->inc6_laddr,
377 		    sizeof(struct in6_addr));
378 		sa6->sin6_port = inc->inc_lport;
379 		sa6->sin6_family = AF_INET6;
380 		sa6->sin6_len = sizeof(struct sockaddr_in6);
381 
382 		sa6 = (struct sockaddr_in6 *)&fsa;
383 		memcpy(&sa6->sin6_addr, &inc->inc6_faddr,
384 		    sizeof(struct in6_addr));
385 		sa6->sin6_port = inc->inc_fport;
386 		sa6->sin6_family = AF_INET6;
387 		sa6->sin6_len = sizeof(struct sockaddr_in6);
388 	}
389 #endif
390 	else
391 		return NULL;
392 
393 	/*
394 	 * Only take exact matches, any sockets with
395 	 * previously unbound addresses will be deleted
396 	 * below in the display routine because they
397 	 * will appear as ``not seen'' in the kernel
398 	 * data structures.
399 	 */
400 	TAILQ_FOREACH(p, &netcb, chain) {
401 		if (!streq(proto, p->ni_proto))
402 			continue;
403 		if (p->ni_lsa.ss_family != lsa.ss_family ||
404 		    memcmp(&p->ni_lsa, &lsa, lsa.ss_len) != 0)
405 			continue;
406 		if (p->ni_fsa.ss_family == fsa.ss_family &&
407 		    memcmp(&p->ni_fsa, &fsa, fsa.ss_len) == 0)
408 			break;
409 	}
410 	if (p == NULL) {
411 		if ((p = malloc(sizeof(*p))) == NULL) {
412 			error("Out of memory");
413 			return NULL;
414 		}
415 		TAILQ_INSERT_HEAD(&netcb, p, chain);
416 		p->ni_line = -1;
417 		memcpy(&p->ni_lsa, &lsa, lsa.ss_len);
418 		memcpy(&p->ni_fsa, &fsa, fsa.ss_len);
419 		p->ni_proto = strdup(proto);
420 		p->ni_flags = NIF_LACHG|NIF_FACHG;
421 	}
422 	p->ni_state = state;
423 	p->ni_seen = 1;
424 	return p;
425 }
426 
427 /* column locations */
428 #define	LADDR	0
429 #define	FADDR	LADDR+23
430 #define	PROTO	FADDR+23
431 #define	RCVCC	PROTO+6
432 #define	SNDCC	RCVCC+7
433 #define	STATE	SNDCC+7
434 
435 void
436 labelnetstat(void)
437 {
438 	if (use_kvm && namelist[X_TCB].n_type == 0)
439 		return;
440 	wmove(wnd, 0, 0); wclrtobot(wnd);
441 	mvwaddstr(wnd, 0, LADDR, "Local Address");
442 	mvwaddstr(wnd, 0, FADDR, "Foreign Address");
443 	mvwaddstr(wnd, 0, PROTO, "Proto");
444 	mvwaddstr(wnd, 0, RCVCC, "Recv-Q");
445 	mvwaddstr(wnd, 0, SNDCC, "Send-Q");
446 	mvwaddstr(wnd, 0, STATE, "(state)");
447 }
448 
449 void
450 shownetstat(void)
451 {
452 	struct netinfo *p, *q;
453 	char proto[6];
454 	const char *family = "";
455 
456 	/*
457 	 * First, delete any connections that have gone
458 	 * away and adjust the position of connections
459 	 * below to reflect the deleted line.
460 	 */
461 	p = TAILQ_FIRST(&netcb);
462 	while (p != NULL) {
463 		if (p->ni_line == -1 || p->ni_seen) {
464 			p = TAILQ_NEXT(p, chain);
465 			continue;
466 		}
467 		wmove(wnd, p->ni_line, 0); wdeleteln(wnd);
468 		TAILQ_FOREACH(q, &netcb, chain)
469 			if (q != p && q->ni_line > p->ni_line) {
470 				q->ni_line--;
471 				/* this shouldn't be necessary */
472 				q->ni_flags |= NIF_LACHG|NIF_FACHG;
473 			}
474 		lastrow--;
475 		q = TAILQ_NEXT(p, chain);
476 		TAILQ_REMOVE(&netcb, p, chain);
477 		free(p);
478 		p = q;
479 	}
480 	/*
481 	 * Update existing connections and add new ones.
482 	 */
483 	TAILQ_FOREACH(p, &netcb, chain) {
484 		if (p->ni_line == -1) {
485 			/*
486 			 * Add a new entry if possible.
487 			 */
488 			if (lastrow > YMAX(wnd))
489 				continue;
490 			p->ni_line = lastrow++;
491 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
492 		}
493 		if (p->ni_flags & NIF_LACHG) {
494 			wmove(wnd, p->ni_line, LADDR);
495 			inetprint((struct sockaddr *)&p->ni_lsa, p->ni_proto);
496 			p->ni_flags &= ~NIF_LACHG;
497 		}
498 		if (p->ni_flags & NIF_FACHG) {
499 			wmove(wnd, p->ni_line, FADDR);
500 			inetprint((struct sockaddr *)&p->ni_fsa, p->ni_proto);
501 			p->ni_flags &= ~NIF_FACHG;
502 		}
503 #ifdef INET6
504 		family = (p->ni_lsa.ss_family == AF_INET) ? "4" : "6";
505 #endif
506 		snprintf(proto, sizeof(proto), "%s%s", p->ni_proto, family);
507 		mvwaddstr(wnd, p->ni_line, PROTO, proto);
508 		mvwprintw(wnd, p->ni_line, RCVCC, "%6u", p->ni_rcvcc);
509 		mvwprintw(wnd, p->ni_line, SNDCC, "%6u", p->ni_sndcc);
510 		if (streq(p->ni_proto, "tcp")) {
511 			if (p->ni_state < 0 || p->ni_state >= TCP_NSTATES)
512 				mvwprintw(wnd, p->ni_line, STATE, "%d",
513 				    p->ni_state);
514 			else
515 				mvwaddstr(wnd, p->ni_line, STATE,
516 				    tcpstates[p->ni_state]);
517 		}
518 		wclrtoeol(wnd);
519 	}
520 	if (lastrow < YMAX(wnd)) {
521 		wmove(wnd, lastrow, 0); wclrtobot(wnd);
522 		wmove(wnd, YMAX(wnd), 0); wdeleteln(wnd);	/* XXX */
523 	}
524 }
525 
526 /*
527  * Pretty print an Internet address (net address + port).
528  * If the nflag was specified, use numbers instead of names.
529  */
530 static void
531 inetprint(struct sockaddr *sa, const char *proto)
532 {
533 	struct servent *sp = 0;
534 	char line[80], *cp;
535 	int port;
536 
537 	switch (sa->sa_family) {
538 	case AF_INET:
539 		port = ((struct sockaddr_in *)sa)->sin_port;
540 		break;
541 #ifdef INET6
542 	case AF_INET6:
543 		port = ((struct sockaddr_in6 *)sa)->sin6_port;
544 		break;
545 #endif
546 	default:
547 		port = 0;
548 		break;
549 	}
550 	snprintf(line, sizeof(line), "%.*s.", 16, inetname(sa));
551 	cp = strchr(line, '\0');
552 	if (!nflag && port)
553 		sp = getservbyport(port, proto);
554 	if (sp || port == 0)
555 		snprintf(cp, sizeof(line) - (cp - line), "%.8s",
556 		    sp ? sp->s_name : "*");
557 	else
558 		snprintf(cp, sizeof(line) - (cp - line), "%d",
559 		    ntohs((u_short)port));
560 	/* pad to full column to clear any garbage */
561 	cp = strchr(line, '\0');
562 	while (cp - line < 22)
563 		*cp++ = ' ';
564 	line[22] = '\0';
565 	waddstr(wnd, line);
566 }
567 
568 /*
569  * Construct an Internet address representation.
570  * If the nflag has been supplied, give
571  * numeric value, otherwise try for symbolic name.
572  */
573 static char *
574 inetname(struct sockaddr *sa)
575 {
576 	char *cp = 0;
577 	static char line[NI_MAXHOST];
578 	struct hostent *hp;
579 	struct in_addr in;
580 
581 #ifdef INET6
582 	if (sa->sa_family == AF_INET6) {
583 		if (memcmp(&((struct sockaddr_in6 *)sa)->sin6_addr,
584 		    &in6addr_any, sizeof(in6addr_any)) == 0)
585 			strcpy(line, "*");
586 		else
587 			getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
588 			    nflag ? NI_NUMERICHOST : 0);
589 		return (line);
590 	}
591 #endif
592 
593 	in = ((struct sockaddr_in *)sa)->sin_addr;
594 	if (!nflag && in.s_addr != INADDR_ANY) {
595 		hp = gethostbyaddr((char *)&in, sizeof (in), AF_INET);
596 		if (hp)
597 			cp = hp->h_name;
598 	}
599 	if (in.s_addr == INADDR_ANY)
600 		strcpy(line, "*");
601 	else if (cp)
602 		snprintf(line, sizeof(line), "%s", cp);
603 	else {
604 		in.s_addr = ntohl(in.s_addr);
605 #define C(x)	((x) & 0xff)
606 		snprintf(line, sizeof(line), "%u.%u.%u.%u", C(in.s_addr >> 24),
607 			C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
608 	}
609 	return (line);
610 }
611 
612 int
613 cmdnetstat(const char *cmd, const char *args)
614 {
615 	if (prefix(cmd, "all")) {
616 		aflag = !aflag;
617 		goto fixup;
618 	}
619 	if  (prefix(cmd, "numbers") || prefix(cmd, "names")) {
620 		struct netinfo *p;
621 		int new;
622 
623 		new = prefix(cmd, "numbers");
624 		if (new == nflag)
625 			return (1);
626 		TAILQ_FOREACH(p, &netcb, chain) {
627 			if (p->ni_line == -1)
628 				continue;
629 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
630 		}
631 		nflag = new;
632 		goto redisplay;
633 	}
634 	if (!netcmd(cmd, args))
635 		return (0);
636 fixup:
637 	fetchnetstat();
638 redisplay:
639 	shownetstat();
640 	refresh();
641 	return (1);
642 }
643