xref: /freebsd/usr.bin/systat/netstat.c (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0) 
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 netinfo *p;
172 	struct inpcbhead head;
173 	struct socket sockb;
174 	struct tcpcb tcpcb;
175 	struct inpcb *inpcb;
176 	void *off;
177 	int istcp;
178 
179 	if (namelist[X_TCB].n_value == 0)
180 		return;
181 	TAILQ_FOREACH(p, &netcb, chain)
182 		p->ni_seen = 0;
183 	if (protos&TCP) {
184 		off = NPTR(X_TCB);
185 		istcp = 1;
186 	}
187 	else if (protos&UDP) {
188 		off = NPTR(X_UDB);
189 		istcp = 0;
190 	}
191 	else {
192 		error("No protocols to display");
193 		return;
194 	}
195 again:
196 	KREAD(off, &head, sizeof (struct inpcbhead));
197 	LIST_FOREACH(inpcb, &head, inp_list) {
198 		KREAD(inpcb, &tcpcb, istcp ? sizeof(tcpcb) : sizeof(inpcb));
199 		inpcb = (struct inpcb *)&tcpcb;
200 		if (!aflag) {
201 			if (inpcb->inp_vflag & INP_IPV4) {
202 				if (inpcb->inp_laddr.s_addr == INADDR_ANY)
203 					continue;
204 			}
205 #ifdef INET6
206 			else if (inpcb->inp_vflag & INP_IPV6) {
207 				if (memcmp(&inpcb->in6p_laddr,
208 				    &in6addr_any, sizeof(in6addr_any)) == 0)
209 					continue;
210 			}
211 #endif
212 		}
213 		if (nhosts && !checkhost(&inpcb->inp_inc))
214 			continue;
215 		if (nports && !checkport(&inpcb->inp_inc))
216 			continue;
217 		if (istcp) {
218 			KREAD(inpcb->inp_socket, &sockb, sizeof (sockb));
219 			enter_kvm(inpcb, &sockb, tcpcb.t_state, "tcp");
220 		} else
221 			enter_kvm(inpcb, &sockb, 0, "udp");
222 	}
223 	if (istcp && (protos&UDP)) {
224 		istcp = 0;
225 		off = NPTR(X_UDB);
226 		goto again;
227 	}
228 }
229 
230 static void
231 fetchnetstat_sysctl(void)
232 {
233 	struct netinfo *p;
234 	int idx;
235 	struct xinpgen *inpg;
236 	char *cur, *end;
237 	struct xinpcb *xip = NULL;
238 	struct xtcpcb *xtp = NULL;
239 	int plen;
240 	size_t lsz;
241 
242 	TAILQ_FOREACH(p, &netcb, chain)
243 		p->ni_seen = 0;
244 	if (protos&TCP) {
245 		idx = 0;
246 	} else if (protos&UDP) {
247 		idx = 1;
248 	} else {
249 		error("No protocols to display");
250 		return;
251 	}
252 
253 	for (;idx < 2; idx++) {
254 		if (idx == 1 && !(protos&UDP))
255 			break;
256 		inpg = (struct xinpgen *)sysctl_dynread(miblist[idx], &lsz);
257 		if (inpg == NULL) {
258 			error("sysctl(%s...) failed", miblist[idx]);
259 			continue;
260 		}
261 		/*
262 		 * We currently do no require a consistent pcb list.
263 		 * Try to be robust in case of struct size changes
264 		 */
265 		cur = ((char *)inpg) + inpg->xig_len;
266 		/* There is also a trailing struct xinpgen */
267 		end = ((char *)inpg) + lsz - inpg->xig_len;
268 		if (end <= cur) {
269 			free(inpg);
270 			continue;
271 		}
272 		if (idx == 0) { /* TCP */
273 			xtp = (struct xtcpcb *)cur;
274 			plen = xtp->xt_len;
275 		} else {
276 			xip = (struct xinpcb *)cur;
277 			plen = xip->xi_len;
278 		}
279 		while (cur + plen <= end) {
280 			if (idx == 0) { /* TCP */
281 				xtp = (struct xtcpcb *)cur;
282 				xip = &xtp->xt_inp;
283 			} else {
284 				xip = (struct xinpcb *)cur;
285 			}
286 			cur += plen;
287 
288 			if (!aflag) {
289 				if (xip->inp_vflag & INP_IPV4) {
290 					if (xip->inp_laddr.s_addr == INADDR_ANY)
291 						continue;
292 				}
293 #ifdef INET6
294 				else if (xip->inp_vflag & INP_IPV6) {
295 					if (memcmp(&xip->in6p_laddr,
296 					    &in6addr_any, sizeof(in6addr_any))
297 					    == 0)
298 						continue;
299 				}
300 #endif
301 			}
302 			if (nhosts && !checkhost(&xip->inp_inc))
303 				continue;
304 			if (nports && !checkport(&xip->inp_inc))
305 				continue;
306 			if (idx == 0)
307 				enter_sysctl(xip, &xip->xi_socket,
308 				    xtp->t_state, "tcp");
309 			else
310 				enter_sysctl(xip, &xip->xi_socket, 0, "udp");
311 		}
312 		free(inpg);
313 	}
314 }
315 
316 static void
317 enter_kvm(struct inpcb *inp, struct socket *so, int state, const char *proto)
318 {
319 	struct netinfo *p;
320 
321 	if ((p = enter(&inp->inp_inc, inp->inp_vflag, state, proto)) != NULL) {
322 		p->ni_rcvcc = so->so_rcv.sb_ccc;
323 		p->ni_sndcc = so->so_snd.sb_ccc;
324 	}
325 }
326 
327 static void
328 enter_sysctl(struct xinpcb *xip, struct xsocket *so, int state,
329     const char *proto)
330 {
331 	struct netinfo *p;
332 
333 	if ((p = enter(&xip->inp_inc, xip->inp_vflag, state, proto)) != NULL) {
334 		p->ni_rcvcc = so->so_rcv.sb_cc;
335 		p->ni_sndcc = so->so_snd.sb_cc;
336 	}
337 }
338 
339 static struct netinfo *
340 enter(struct in_conninfo *inc, uint8_t vflag, int state, const char *proto)
341 {
342 	struct netinfo *p;
343 	struct sockaddr_storage lsa, fsa;
344 	struct sockaddr_in *sa4;
345 #ifdef INET6
346 	struct sockaddr_in6 *sa6;
347 #endif
348 
349 	memset(&lsa, 0, sizeof(lsa));
350 	memset(&fsa, 0, sizeof(fsa));
351 	if (vflag & INP_IPV4) {
352 		sa4 = (struct sockaddr_in *)&lsa;
353 		sa4->sin_addr = inc->inc_laddr;
354 		sa4->sin_port = inc->inc_lport;
355 		sa4->sin_family = AF_INET;
356 		sa4->sin_len = sizeof(struct sockaddr_in);
357 
358 		sa4 = (struct sockaddr_in *)&fsa;
359 		sa4->sin_addr = inc->inc_faddr;
360 		sa4->sin_port = inc->inc_fport;
361 		sa4->sin_family = AF_INET;
362 		sa4->sin_len = sizeof(struct sockaddr_in);
363 	}
364 #ifdef INET6
365 	else if (vflag & INP_IPV6) {
366 		sa6 = (struct sockaddr_in6 *)&lsa;
367 		memcpy(&sa6->sin6_addr, &inc->inc6_laddr,
368 		    sizeof(struct in6_addr));
369 		sa6->sin6_port = inc->inc_lport;
370 		sa6->sin6_family = AF_INET6;
371 		sa6->sin6_len = sizeof(struct sockaddr_in6);
372 
373 		sa6 = (struct sockaddr_in6 *)&fsa;
374 		memcpy(&sa6->sin6_addr, &inc->inc6_faddr,
375 		    sizeof(struct in6_addr));
376 		sa6->sin6_port = inc->inc_fport;
377 		sa6->sin6_family = AF_INET6;
378 		sa6->sin6_len = sizeof(struct sockaddr_in6);
379 	}
380 #endif
381 	else
382 		return NULL;
383 
384 	/*
385 	 * Only take exact matches, any sockets with
386 	 * previously unbound addresses will be deleted
387 	 * below in the display routine because they
388 	 * will appear as ``not seen'' in the kernel
389 	 * data structures.
390 	 */
391 	TAILQ_FOREACH(p, &netcb, chain) {
392 		if (!streq(proto, p->ni_proto))
393 			continue;
394 		if (p->ni_lsa.ss_family != lsa.ss_family ||
395 		    memcmp(&p->ni_lsa, &lsa, lsa.ss_len) != 0)
396 			continue;
397 		if (p->ni_fsa.ss_family == fsa.ss_family &&
398 		    memcmp(&p->ni_fsa, &fsa, fsa.ss_len) == 0)
399 			break;
400 	}
401 	if (p == NULL) {
402 		if ((p = malloc(sizeof(*p))) == NULL) {
403 			error("Out of memory");
404 			return NULL;
405 		}
406 		TAILQ_INSERT_HEAD(&netcb, p, chain);
407 		p->ni_line = -1;
408 		memcpy(&p->ni_lsa, &lsa, lsa.ss_len);
409 		memcpy(&p->ni_fsa, &fsa, fsa.ss_len);
410 		p->ni_proto = strdup(proto);
411 		p->ni_flags = NIF_LACHG|NIF_FACHG;
412 	}
413 	p->ni_state = state;
414 	p->ni_seen = 1;
415 	return p;
416 }
417 
418 /* column locations */
419 #define	LADDR	0
420 #define	FADDR	LADDR+23
421 #define	PROTO	FADDR+23
422 #define	RCVCC	PROTO+6
423 #define	SNDCC	RCVCC+7
424 #define	STATE	SNDCC+7
425 
426 void
427 labelnetstat(void)
428 {
429 	if (use_kvm && namelist[X_TCB].n_type == 0)
430 		return;
431 	wmove(wnd, 0, 0); wclrtobot(wnd);
432 	mvwaddstr(wnd, 0, LADDR, "Local Address");
433 	mvwaddstr(wnd, 0, FADDR, "Foreign Address");
434 	mvwaddstr(wnd, 0, PROTO, "Proto");
435 	mvwaddstr(wnd, 0, RCVCC, "Recv-Q");
436 	mvwaddstr(wnd, 0, SNDCC, "Send-Q");
437 	mvwaddstr(wnd, 0, STATE, "(state)");
438 }
439 
440 void
441 shownetstat(void)
442 {
443 	struct netinfo *p, *q;
444 	char proto[6];
445 	const char *family = "";
446 
447 	/*
448 	 * First, delete any connections that have gone
449 	 * away and adjust the position of connections
450 	 * below to reflect the deleted line.
451 	 */
452 	p = TAILQ_FIRST(&netcb);
453 	while (p != NULL) {
454 		if (p->ni_line == -1 || p->ni_seen) {
455 			p = TAILQ_NEXT(p, chain);
456 			continue;
457 		}
458 		wmove(wnd, p->ni_line, 0); wdeleteln(wnd);
459 		TAILQ_FOREACH(q, &netcb, chain)
460 			if (q != p && q->ni_line > p->ni_line) {
461 				q->ni_line--;
462 				/* this shouldn't be necessary */
463 				q->ni_flags |= NIF_LACHG|NIF_FACHG;
464 			}
465 		lastrow--;
466 		q = TAILQ_NEXT(p, chain);
467 		TAILQ_REMOVE(&netcb, p, chain);
468 		free(p);
469 		p = q;
470 	}
471 	/*
472 	 * Update existing connections and add new ones.
473 	 */
474 	TAILQ_FOREACH(p, &netcb, chain) {
475 		if (p->ni_line == -1) {
476 			/*
477 			 * Add a new entry if possible.
478 			 */
479 			if (lastrow > YMAX(wnd))
480 				continue;
481 			p->ni_line = lastrow++;
482 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
483 		}
484 		if (p->ni_flags & NIF_LACHG) {
485 			wmove(wnd, p->ni_line, LADDR);
486 			inetprint((struct sockaddr *)&p->ni_lsa, p->ni_proto);
487 			p->ni_flags &= ~NIF_LACHG;
488 		}
489 		if (p->ni_flags & NIF_FACHG) {
490 			wmove(wnd, p->ni_line, FADDR);
491 			inetprint((struct sockaddr *)&p->ni_fsa, p->ni_proto);
492 			p->ni_flags &= ~NIF_FACHG;
493 		}
494 #ifdef INET6
495 		family = (p->ni_lsa.ss_family == AF_INET) ? "4" : "6";
496 #endif
497 		snprintf(proto, sizeof(proto), "%s%s", p->ni_proto, family);
498 		mvwaddstr(wnd, p->ni_line, PROTO, proto);
499 		mvwprintw(wnd, p->ni_line, RCVCC, "%6u", p->ni_rcvcc);
500 		mvwprintw(wnd, p->ni_line, SNDCC, "%6u", p->ni_sndcc);
501 		if (streq(p->ni_proto, "tcp")) {
502 			if (p->ni_state < 0 || p->ni_state >= TCP_NSTATES)
503 				mvwprintw(wnd, p->ni_line, STATE, "%d",
504 				    p->ni_state);
505 			else
506 				mvwaddstr(wnd, p->ni_line, STATE,
507 				    tcpstates[p->ni_state]);
508 		}
509 		wclrtoeol(wnd);
510 	}
511 	if (lastrow < YMAX(wnd)) {
512 		wmove(wnd, lastrow, 0); wclrtobot(wnd);
513 		wmove(wnd, YMAX(wnd), 0); wdeleteln(wnd);	/* XXX */
514 	}
515 }
516 
517 /*
518  * Pretty print an Internet address (net address + port).
519  * If the nflag was specified, use numbers instead of names.
520  */
521 static void
522 inetprint(struct sockaddr *sa, const char *proto)
523 {
524 	struct servent *sp = 0;
525 	char line[80], *cp;
526 	int port;
527 
528 	switch (sa->sa_family) {
529 	case AF_INET:
530 		port = ((struct sockaddr_in *)sa)->sin_port;
531 		break;
532 #ifdef INET6
533 	case AF_INET6:
534 		port = ((struct sockaddr_in6 *)sa)->sin6_port;
535 		break;
536 #endif
537 	default:
538 		port = 0;
539 		break;
540 	}
541 	snprintf(line, sizeof(line), "%.*s.", 16, inetname(sa));
542 	cp = strchr(line, '\0');
543 	if (!nflag && port)
544 		sp = getservbyport(port, proto);
545 	if (sp || port == 0)
546 		snprintf(cp, sizeof(line) - (cp - line), "%.8s",
547 		    sp ? sp->s_name : "*");
548 	else
549 		snprintf(cp, sizeof(line) - (cp - line), "%d",
550 		    ntohs((u_short)port));
551 	/* pad to full column to clear any garbage */
552 	cp = strchr(line, '\0');
553 	while (cp - line < 22)
554 		*cp++ = ' ';
555 	line[22] = '\0';
556 	waddstr(wnd, line);
557 }
558 
559 /*
560  * Construct an Internet address representation.
561  * If the nflag has been supplied, give
562  * numeric value, otherwise try for symbolic name.
563  */
564 static char *
565 inetname(struct sockaddr *sa)
566 {
567 	char *cp = 0;
568 	static char line[NI_MAXHOST];
569 	struct hostent *hp;
570 	struct in_addr in;
571 
572 #ifdef INET6
573 	if (sa->sa_family == AF_INET6) {
574 		if (memcmp(&((struct sockaddr_in6 *)sa)->sin6_addr,
575 		    &in6addr_any, sizeof(in6addr_any)) == 0)
576 			strcpy(line, "*");
577 		else
578 			getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
579 			    nflag ? NI_NUMERICHOST : 0);
580 		return (line);
581 	}
582 #endif
583 
584 	in = ((struct sockaddr_in *)sa)->sin_addr;
585 	if (!nflag && in.s_addr != INADDR_ANY) {
586 		hp = gethostbyaddr((char *)&in, sizeof (in), AF_INET);
587 		if (hp)
588 			cp = hp->h_name;
589 	}
590 	if (in.s_addr == INADDR_ANY)
591 		strcpy(line, "*");
592 	else if (cp)
593 		snprintf(line, sizeof(line), "%s", cp);
594 	else {
595 		in.s_addr = ntohl(in.s_addr);
596 #define C(x)	((x) & 0xff)
597 		snprintf(line, sizeof(line), "%u.%u.%u.%u", C(in.s_addr >> 24),
598 			C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
599 	}
600 	return (line);
601 }
602 
603 int
604 cmdnetstat(const char *cmd, const char *args)
605 {
606 	if (prefix(cmd, "all")) {
607 		aflag = !aflag;
608 		goto fixup;
609 	}
610 	if  (prefix(cmd, "numbers") || prefix(cmd, "names")) {
611 		struct netinfo *p;
612 		int new;
613 
614 		new = prefix(cmd, "numbers");
615 		if (new == nflag)
616 			return (1);
617 		TAILQ_FOREACH(p, &netcb, chain) {
618 			if (p->ni_line == -1)
619 				continue;
620 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
621 		}
622 		nflag = new;
623 		goto redisplay;
624 	}
625 	if (!netcmd(cmd, args))
626 		return (0);
627 fixup:
628 	fetchnetstat();
629 redisplay:
630 	shownetstat();
631 	refresh();
632 	return (1);
633 }
634