xref: /freebsd/usr.bin/systat/netstat.c (revision 2e3f49888ec8851bafb22011533217487764fdb0) 
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 
33 
34 /*
35  * netstat
36  */
37 #include <sys/param.h>
38 #include <sys/queue.h>
39 #include <sys/socket.h>
40 #include <sys/callout.h>
41 #define	_WANT_SOCKET
42 #include <sys/socketvar.h>
43 #include <sys/protosw.h>
44 
45 #include <netinet/in.h>
46 #include <arpa/inet.h>
47 #include <net/route.h>
48 #include <netinet/in_systm.h>
49 #include <netinet/ip.h>
50 #ifdef INET6
51 #include <netinet/ip6.h>
52 #endif
53 #define	_WANT_INPCB
54 #include <netinet/in_pcb.h>
55 #include <netinet/ip_icmp.h>
56 #include <netinet/icmp_var.h>
57 #include <netinet/ip_var.h>
58 #include <netinet/tcp.h>
59 #include <netinet/tcpip.h>
60 #include <netinet/tcp_seq.h>
61 #define TCPSTATES
62 #include <netinet/tcp_fsm.h>
63 #include <netinet/tcp_timer.h>
64 #define	_WANT_TCPCB
65 #include <netinet/tcp_var.h>
66 #include <netinet/udp.h>
67 #include <netinet/udp_var.h>
68 
69 #include <netdb.h>
70 #include <nlist.h>
71 #include <paths.h>
72 #include <stdlib.h>
73 #include <string.h>
74 
75 #include "systat.h"
76 #include "extern.h"
77 
78 static struct netinfo *enter(struct in_conninfo *, uint8_t, int, const char *);
79 static void enter_kvm(struct inpcb *, struct socket *, int, const char *);
80 static void enter_sysctl(struct xinpcb *, struct xsocket *, int, const char *);
81 static void fetchnetstat_kvm(void);
82 static void fetchnetstat_sysctl(void);
83 static char *inetname(struct sockaddr *);
84 static void inetprint(struct sockaddr *, const char *);
85 
86 #define	streq(a,b)	(strcmp(a,b)==0)
87 #define	YMAX(w)		(getmaxy(w)-2)
88 
89 WINDOW *
90 opennetstat(void)
91 {
92 	sethostent(1);
93 	setnetent(1);
94 	return (subwin(stdscr, LINES-3-1, 0, MAINWIN_ROW, 0));
95 }
96 
97 struct netinfo {
98 	TAILQ_ENTRY(netinfo) chain;
99 	short	ni_line;		/* line on screen */
100 	short	ni_seen;		/* 0 when not present in list */
101 	short	ni_flags;
102 #define	NIF_LACHG	0x1		/* local address changed */
103 #define	NIF_FACHG	0x2		/* foreign address changed */
104 	short	ni_state;		/* tcp state */
105 	const char	*ni_proto;		/* protocol */
106 	struct sockaddr_storage ni_lsa;	/* local address */
107 	struct sockaddr_storage	ni_fsa;	/* foreign address */
108 	u_int	ni_rcvcc;		/* rcv buffer character count */
109 	u_int	ni_sndcc;		/* snd buffer character count */
110 };
111 
112 static TAILQ_HEAD(netinfohead, netinfo) netcb = TAILQ_HEAD_INITIALIZER(netcb);
113 
114 static	int aflag = 0;
115 static	int nflag = 0;
116 static	int lastrow = 1;
117 
118 void
119 closenetstat(WINDOW *w)
120 {
121 	struct netinfo *p;
122 
123 	endhostent();
124 	endnetent();
125 	TAILQ_FOREACH(p, &netcb, chain) {
126 		if (p->ni_line != -1)
127 			lastrow--;
128 		p->ni_line = -1;
129 	}
130 	if (w != NULL) {
131 		wclear(w);
132 		wrefresh(w);
133 		delwin(w);
134 	}
135 }
136 
137 static const char *miblist[] = {
138 	"net.inet.tcp.pcblist",
139 	"net.inet.udp.pcblist"
140 };
141 
142 static char tcb[] = "tcb", udb[] = "udb";
143 
144 struct nlist namelist[] = {
145 #define	X_TCB	0
146 	{ .n_name = tcb },
147 #define	X_UDB	1
148 	{ .n_name = udb },
149 	{ .n_name = NULL },
150 };
151 
152 int
153 initnetstat(void)
154 {
155 	protos = TCP|UDP;
156 	return(1);
157 }
158 
159 void
160 fetchnetstat(void)
161 {
162 	if (use_kvm)
163 		fetchnetstat_kvm();
164 	else
165 		fetchnetstat_sysctl();
166 }
167 
168 static void
169 fetchnetstat_kvm(void)
170 {
171 	struct inpcb *next;
172 	struct netinfo *p;
173 	struct inpcbhead head;
174 	struct inpcb inpcb;
175 	struct socket sockb;
176 	struct tcpcb tcpcb;
177 	void *off;
178 	int istcp;
179 
180 	if (namelist[X_TCB].n_value == 0)
181 		return;
182 	TAILQ_FOREACH(p, &netcb, chain)
183 		p->ni_seen = 0;
184 	if (protos&TCP) {
185 		off = NPTR(X_TCB);
186 		istcp = 1;
187 	}
188 	else if (protos&UDP) {
189 		off = NPTR(X_UDB);
190 		istcp = 0;
191 	}
192 	else {
193 		error("No protocols to display");
194 		return;
195 	}
196 again:
197 	KREAD(off, &head, sizeof (struct inpcbhead));
198 	LIST_FOREACH(next, &head, inp_list) {
199 		KREAD(next, &inpcb, sizeof (inpcb));
200 		next = &inpcb;
201 		if (!aflag) {
202 			if (inpcb.inp_vflag & INP_IPV4) {
203 				if (inpcb.inp_laddr.s_addr == INADDR_ANY)
204 					continue;
205 			}
206 #ifdef INET6
207 			else if (inpcb.inp_vflag & INP_IPV6) {
208 				if (memcmp(&inpcb.in6p_laddr,
209 				    &in6addr_any, sizeof(in6addr_any)) == 0)
210 					continue;
211 			}
212 #endif
213 		}
214 		if (nhosts && !checkhost(&inpcb.inp_inc))
215 			continue;
216 		if (nports && !checkport(&inpcb.inp_inc))
217 			continue;
218 		if (istcp) {
219 			KREAD(inpcb.inp_socket, &sockb, sizeof (sockb));
220 			KREAD(inpcb.inp_ppcb, &tcpcb, sizeof (tcpcb));
221 			enter_kvm(&inpcb, &sockb, tcpcb.t_state, "tcp");
222 		} else
223 			enter_kvm(&inpcb, &sockb, 0, "udp");
224 	}
225 	if (istcp && (protos&UDP)) {
226 		istcp = 0;
227 		off = NPTR(X_UDB);
228 		goto again;
229 	}
230 }
231 
232 static void
233 fetchnetstat_sysctl(void)
234 {
235 	struct netinfo *p;
236 	int idx;
237 	struct xinpgen *inpg;
238 	char *cur, *end;
239 	struct xinpcb *xip = NULL;
240 	struct xtcpcb *xtp = NULL;
241 	int plen;
242 	size_t lsz;
243 
244 	TAILQ_FOREACH(p, &netcb, chain)
245 		p->ni_seen = 0;
246 	if (protos&TCP) {
247 		idx = 0;
248 	} else if (protos&UDP) {
249 		idx = 1;
250 	} else {
251 		error("No protocols to display");
252 		return;
253 	}
254 
255 	for (;idx < 2; idx++) {
256 		if (idx == 1 && !(protos&UDP))
257 			break;
258 		inpg = (struct xinpgen *)sysctl_dynread(miblist[idx], &lsz);
259 		if (inpg == NULL) {
260 			error("sysctl(%s...) failed", miblist[idx]);
261 			continue;
262 		}
263 		/*
264 		 * We currently do no require a consistent pcb list.
265 		 * Try to be robust in case of struct size changes
266 		 */
267 		cur = ((char *)inpg) + inpg->xig_len;
268 		/* There is also a trailing struct xinpgen */
269 		end = ((char *)inpg) + lsz - inpg->xig_len;
270 		if (end <= cur) {
271 			free(inpg);
272 			continue;
273 		}
274 		if (idx == 0) { /* TCP */
275 			xtp = (struct xtcpcb *)cur;
276 			plen = xtp->xt_len;
277 		} else {
278 			xip = (struct xinpcb *)cur;
279 			plen = xip->xi_len;
280 		}
281 		while (cur + plen <= end) {
282 			if (idx == 0) { /* TCP */
283 				xtp = (struct xtcpcb *)cur;
284 				xip = &xtp->xt_inp;
285 			} else {
286 				xip = (struct xinpcb *)cur;
287 			}
288 			cur += plen;
289 
290 			if (!aflag) {
291 				if (xip->inp_vflag & INP_IPV4) {
292 					if (xip->inp_laddr.s_addr == INADDR_ANY)
293 						continue;
294 				}
295 #ifdef INET6
296 				else if (xip->inp_vflag & INP_IPV6) {
297 					if (memcmp(&xip->in6p_laddr,
298 					    &in6addr_any, sizeof(in6addr_any))
299 					    == 0)
300 						continue;
301 				}
302 #endif
303 			}
304 			if (nhosts && !checkhost(&xip->inp_inc))
305 				continue;
306 			if (nports && !checkport(&xip->inp_inc))
307 				continue;
308 			if (idx == 0)
309 				enter_sysctl(xip, &xip->xi_socket,
310 				    xtp->t_state, "tcp");
311 			else
312 				enter_sysctl(xip, &xip->xi_socket, 0, "udp");
313 		}
314 		free(inpg);
315 	}
316 }
317 
318 static void
319 enter_kvm(struct inpcb *inp, struct socket *so, int state, const char *proto)
320 {
321 	struct netinfo *p;
322 
323 	if ((p = enter(&inp->inp_inc, inp->inp_vflag, state, proto)) != NULL) {
324 		p->ni_rcvcc = so->so_rcv.sb_ccc;
325 		p->ni_sndcc = so->so_snd.sb_ccc;
326 	}
327 }
328 
329 static void
330 enter_sysctl(struct xinpcb *xip, struct xsocket *so, int state,
331     const char *proto)
332 {
333 	struct netinfo *p;
334 
335 	if ((p = enter(&xip->inp_inc, xip->inp_vflag, state, proto)) != NULL) {
336 		p->ni_rcvcc = so->so_rcv.sb_cc;
337 		p->ni_sndcc = so->so_snd.sb_cc;
338 	}
339 }
340 
341 static struct netinfo *
342 enter(struct in_conninfo *inc, uint8_t vflag, int state, const char *proto)
343 {
344 	struct netinfo *p;
345 	struct sockaddr_storage lsa, fsa;
346 	struct sockaddr_in *sa4;
347 #ifdef INET6
348 	struct sockaddr_in6 *sa6;
349 #endif
350 
351 	memset(&lsa, 0, sizeof(lsa));
352 	memset(&fsa, 0, sizeof(fsa));
353 	if (vflag & INP_IPV4) {
354 		sa4 = (struct sockaddr_in *)&lsa;
355 		sa4->sin_addr = inc->inc_laddr;
356 		sa4->sin_port = inc->inc_lport;
357 		sa4->sin_family = AF_INET;
358 		sa4->sin_len = sizeof(struct sockaddr_in);
359 
360 		sa4 = (struct sockaddr_in *)&fsa;
361 		sa4->sin_addr = inc->inc_faddr;
362 		sa4->sin_port = inc->inc_fport;
363 		sa4->sin_family = AF_INET;
364 		sa4->sin_len = sizeof(struct sockaddr_in);
365 	}
366 #ifdef INET6
367 	else if (vflag & INP_IPV6) {
368 		sa6 = (struct sockaddr_in6 *)&lsa;
369 		memcpy(&sa6->sin6_addr, &inc->inc6_laddr,
370 		    sizeof(struct in6_addr));
371 		sa6->sin6_port = inc->inc_lport;
372 		sa6->sin6_family = AF_INET6;
373 		sa6->sin6_len = sizeof(struct sockaddr_in6);
374 
375 		sa6 = (struct sockaddr_in6 *)&fsa;
376 		memcpy(&sa6->sin6_addr, &inc->inc6_faddr,
377 		    sizeof(struct in6_addr));
378 		sa6->sin6_port = inc->inc_fport;
379 		sa6->sin6_family = AF_INET6;
380 		sa6->sin6_len = sizeof(struct sockaddr_in6);
381 	}
382 #endif
383 	else
384 		return NULL;
385 
386 	/*
387 	 * Only take exact matches, any sockets with
388 	 * previously unbound addresses will be deleted
389 	 * below in the display routine because they
390 	 * will appear as ``not seen'' in the kernel
391 	 * data structures.
392 	 */
393 	TAILQ_FOREACH(p, &netcb, chain) {
394 		if (!streq(proto, p->ni_proto))
395 			continue;
396 		if (p->ni_lsa.ss_family != lsa.ss_family ||
397 		    memcmp(&p->ni_lsa, &lsa, lsa.ss_len) != 0)
398 			continue;
399 		if (p->ni_fsa.ss_family == fsa.ss_family &&
400 		    memcmp(&p->ni_fsa, &fsa, fsa.ss_len) == 0)
401 			break;
402 	}
403 	if (p == NULL) {
404 		if ((p = malloc(sizeof(*p))) == NULL) {
405 			error("Out of memory");
406 			return NULL;
407 		}
408 		TAILQ_INSERT_HEAD(&netcb, p, chain);
409 		p->ni_line = -1;
410 		memcpy(&p->ni_lsa, &lsa, lsa.ss_len);
411 		memcpy(&p->ni_fsa, &fsa, fsa.ss_len);
412 		p->ni_proto = strdup(proto);
413 		p->ni_flags = NIF_LACHG|NIF_FACHG;
414 	}
415 	p->ni_state = state;
416 	p->ni_seen = 1;
417 	return p;
418 }
419 
420 /* column locations */
421 #define	LADDR	0
422 #define	FADDR	LADDR+23
423 #define	PROTO	FADDR+23
424 #define	RCVCC	PROTO+6
425 #define	SNDCC	RCVCC+7
426 #define	STATE	SNDCC+7
427 
428 void
429 labelnetstat(void)
430 {
431 	if (use_kvm && namelist[X_TCB].n_type == 0)
432 		return;
433 	wmove(wnd, 0, 0); wclrtobot(wnd);
434 	mvwaddstr(wnd, 0, LADDR, "Local Address");
435 	mvwaddstr(wnd, 0, FADDR, "Foreign Address");
436 	mvwaddstr(wnd, 0, PROTO, "Proto");
437 	mvwaddstr(wnd, 0, RCVCC, "Recv-Q");
438 	mvwaddstr(wnd, 0, SNDCC, "Send-Q");
439 	mvwaddstr(wnd, 0, STATE, "(state)");
440 }
441 
442 void
443 shownetstat(void)
444 {
445 	struct netinfo *p, *q;
446 	char proto[6];
447 	const char *family = "";
448 
449 	/*
450 	 * First, delete any connections that have gone
451 	 * away and adjust the position of connections
452 	 * below to reflect the deleted line.
453 	 */
454 	p = TAILQ_FIRST(&netcb);
455 	while (p != NULL) {
456 		if (p->ni_line == -1 || p->ni_seen) {
457 			p = TAILQ_NEXT(p, chain);
458 			continue;
459 		}
460 		wmove(wnd, p->ni_line, 0); wdeleteln(wnd);
461 		TAILQ_FOREACH(q, &netcb, chain)
462 			if (q != p && q->ni_line > p->ni_line) {
463 				q->ni_line--;
464 				/* this shouldn't be necessary */
465 				q->ni_flags |= NIF_LACHG|NIF_FACHG;
466 			}
467 		lastrow--;
468 		q = TAILQ_NEXT(p, chain);
469 		TAILQ_REMOVE(&netcb, p, chain);
470 		free(p);
471 		p = q;
472 	}
473 	/*
474 	 * Update existing connections and add new ones.
475 	 */
476 	TAILQ_FOREACH(p, &netcb, chain) {
477 		if (p->ni_line == -1) {
478 			/*
479 			 * Add a new entry if possible.
480 			 */
481 			if (lastrow > YMAX(wnd))
482 				continue;
483 			p->ni_line = lastrow++;
484 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
485 		}
486 		if (p->ni_flags & NIF_LACHG) {
487 			wmove(wnd, p->ni_line, LADDR);
488 			inetprint((struct sockaddr *)&p->ni_lsa, p->ni_proto);
489 			p->ni_flags &= ~NIF_LACHG;
490 		}
491 		if (p->ni_flags & NIF_FACHG) {
492 			wmove(wnd, p->ni_line, FADDR);
493 			inetprint((struct sockaddr *)&p->ni_fsa, p->ni_proto);
494 			p->ni_flags &= ~NIF_FACHG;
495 		}
496 #ifdef INET6
497 		family = (p->ni_lsa.ss_family == AF_INET) ? "4" : "6";
498 #endif
499 		snprintf(proto, sizeof(proto), "%s%s", p->ni_proto, family);
500 		mvwaddstr(wnd, p->ni_line, PROTO, proto);
501 		mvwprintw(wnd, p->ni_line, RCVCC, "%6u", p->ni_rcvcc);
502 		mvwprintw(wnd, p->ni_line, SNDCC, "%6u", p->ni_sndcc);
503 		if (streq(p->ni_proto, "tcp")) {
504 			if (p->ni_state < 0 || p->ni_state >= TCP_NSTATES)
505 				mvwprintw(wnd, p->ni_line, STATE, "%d",
506 				    p->ni_state);
507 			else
508 				mvwaddstr(wnd, p->ni_line, STATE,
509 				    tcpstates[p->ni_state]);
510 		}
511 		wclrtoeol(wnd);
512 	}
513 	if (lastrow < YMAX(wnd)) {
514 		wmove(wnd, lastrow, 0); wclrtobot(wnd);
515 		wmove(wnd, YMAX(wnd), 0); wdeleteln(wnd);	/* XXX */
516 	}
517 }
518 
519 /*
520  * Pretty print an Internet address (net address + port).
521  * If the nflag was specified, use numbers instead of names.
522  */
523 static void
524 inetprint(struct sockaddr *sa, const char *proto)
525 {
526 	struct servent *sp = 0;
527 	char line[80], *cp;
528 	int port;
529 
530 	switch (sa->sa_family) {
531 	case AF_INET:
532 		port = ((struct sockaddr_in *)sa)->sin_port;
533 		break;
534 #ifdef INET6
535 	case AF_INET6:
536 		port = ((struct sockaddr_in6 *)sa)->sin6_port;
537 		break;
538 #endif
539 	default:
540 		port = 0;
541 		break;
542 	}
543 	snprintf(line, sizeof(line), "%.*s.", 16, inetname(sa));
544 	cp = strchr(line, '\0');
545 	if (!nflag && port)
546 		sp = getservbyport(port, proto);
547 	if (sp || port == 0)
548 		snprintf(cp, sizeof(line) - (cp - line), "%.8s",
549 		    sp ? sp->s_name : "*");
550 	else
551 		snprintf(cp, sizeof(line) - (cp - line), "%d",
552 		    ntohs((u_short)port));
553 	/* pad to full column to clear any garbage */
554 	cp = strchr(line, '\0');
555 	while (cp - line < 22)
556 		*cp++ = ' ';
557 	line[22] = '\0';
558 	waddstr(wnd, line);
559 }
560 
561 /*
562  * Construct an Internet address representation.
563  * If the nflag has been supplied, give
564  * numeric value, otherwise try for symbolic name.
565  */
566 static char *
567 inetname(struct sockaddr *sa)
568 {
569 	char *cp = 0;
570 	static char line[NI_MAXHOST];
571 	struct hostent *hp;
572 	struct in_addr in;
573 
574 #ifdef INET6
575 	if (sa->sa_family == AF_INET6) {
576 		if (memcmp(&((struct sockaddr_in6 *)sa)->sin6_addr,
577 		    &in6addr_any, sizeof(in6addr_any)) == 0)
578 			strcpy(line, "*");
579 		else
580 			getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
581 			    nflag ? NI_NUMERICHOST : 0);
582 		return (line);
583 	}
584 #endif
585 
586 	in = ((struct sockaddr_in *)sa)->sin_addr;
587 	if (!nflag && in.s_addr != INADDR_ANY) {
588 		hp = gethostbyaddr((char *)&in, sizeof (in), AF_INET);
589 		if (hp)
590 			cp = hp->h_name;
591 	}
592 	if (in.s_addr == INADDR_ANY)
593 		strcpy(line, "*");
594 	else if (cp)
595 		snprintf(line, sizeof(line), "%s", cp);
596 	else {
597 		in.s_addr = ntohl(in.s_addr);
598 #define C(x)	((x) & 0xff)
599 		snprintf(line, sizeof(line), "%u.%u.%u.%u", C(in.s_addr >> 24),
600 			C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
601 	}
602 	return (line);
603 }
604 
605 int
606 cmdnetstat(const char *cmd, const char *args)
607 {
608 	if (prefix(cmd, "all")) {
609 		aflag = !aflag;
610 		goto fixup;
611 	}
612 	if  (prefix(cmd, "numbers") || prefix(cmd, "names")) {
613 		struct netinfo *p;
614 		int new;
615 
616 		new = prefix(cmd, "numbers");
617 		if (new == nflag)
618 			return (1);
619 		TAILQ_FOREACH(p, &netcb, chain) {
620 			if (p->ni_line == -1)
621 				continue;
622 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
623 		}
624 		nflag = new;
625 		goto redisplay;
626 	}
627 	if (!netcmd(cmd, args))
628 		return (0);
629 fixup:
630 	fetchnetstat();
631 redisplay:
632 	shownetstat();
633 	refresh();
634 	return (1);
635 }
636