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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/net/rcmd.c	Lines:	0	156	0.0 %
Date:	2017-11-13	Branches:	0	92	0.0 %


/*
 * Copyright (c) 1995, 1996, 1998 Theo de Raadt.  All rights reserved.
 * Copyright (c) 1983, 1993, 1994
 *	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.
 */

#include <sys/socket.h>
#include <sys/stat.h>

#include <netinet/in.h>
#include <arpa/inet.h>

#include <signal.h>
#include <fcntl.h>
#include <netdb.h>
#include <unistd.h>
#include <limits.h>
#include <pwd.h>
#include <errno.h>
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <stdlib.h>
#include <poll.h>

int
rcmd(char **ahost, int rport, const char *locuser, const char *remuser,
    const char *cmd, int *fd2p)
{
	return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
}

int
rcmd_af(char **ahost, int porta, const char *locuser, const char *remuser,
    const char *cmd, int *fd2p, int af)
{
	static char hbuf[HOST_NAME_MAX+1];
	char pbuf[NI_MAXSERV];
	struct addrinfo hints, *res, *r;
	int error;
	struct sockaddr_storage from;
	sigset_t oldmask, mask;
	pid_t pid;
	int s, lport;
	struct timespec timo;
	char c, *p;
	int refused;
	in_port_t rport = porta;
	int numread;

	/* call rcmdsh() with specified remote shell if appropriate. */
	if (!issetugid() && (p = getenv("RSH")) && *p) {
		struct servent *sp = getservbyname("shell", "tcp");

		if (sp && sp->s_port == rport)
			return (rcmdsh(ahost, rport, locuser, remuser,
			    cmd, p));
	}

	/* use rsh(1) if non-root and remote port is shell. */
	if (geteuid()) {
		struct servent *sp = getservbyname("shell", "tcp");

		if (sp && sp->s_port == rport)
			return (rcmdsh(ahost, rport, locuser, remuser,
			    cmd, NULL));
	}

	pid = getpid();
	snprintf(pbuf, sizeof(pbuf), "%u", ntohs(rport));
	memset(&hints, 0, sizeof(hints));
	hints.ai_family = af;
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_flags = AI_CANONNAME;
	error = getaddrinfo(*ahost, pbuf, &hints, &res);
	if (error) {
		(void)fprintf(stderr, "rcmd: %s: %s\n", *ahost,
		    gai_strerror(error));
		return (-1);
	}
	if (res->ai_canonname) {
		strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
		*ahost = hbuf;
	} else
		; /*XXX*/

	r = res;
	refused = 0;
	timespecclear(&timo);
	sigemptyset(&mask);
	sigaddset(&mask, SIGURG);
	sigprocmask(SIG_BLOCK, &mask, &oldmask);
	for (timo.tv_sec = 1, lport = IPPORT_RESERVED - 1;;) {
		s = rresvport_af(&lport, r->ai_family);
		if (s < 0) {
			if (errno == EAGAIN)
				(void)fprintf(stderr,
				    "rcmd: socket: All ports in use\n");
			else
				(void)fprintf(stderr, "rcmd: socket: %s\n",
				    strerror(errno));
			if (r->ai_next) {
				r = r->ai_next;
				continue;
			} else {
				sigprocmask(SIG_SETMASK, &oldmask, NULL);
				freeaddrinfo(res);
				return (-1);
			}
		}
		fcntl(s, F_SETOWN, pid);
		if (connect(s, r->ai_addr, r->ai_addrlen) >= 0)
			break;
		(void)close(s);
		if (errno == EADDRINUSE) {
			lport--;
			continue;
		}
		if (errno == ECONNREFUSED)
			refused++;
		if (r->ai_next) {
			int oerrno = errno;
			char hbuf[NI_MAXHOST];
			const int niflags = NI_NUMERICHOST;

			hbuf[0] = '\0';
			if (getnameinfo(r->ai_addr, r->ai_addrlen,
			    hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
				strlcpy(hbuf, "(invalid)", sizeof hbuf);
			(void)fprintf(stderr, "connect to address %s: ", hbuf);
			errno = oerrno;
			perror(0);
			r = r->ai_next;
			hbuf[0] = '\0';
			if (getnameinfo(r->ai_addr, r->ai_addrlen,
			    hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
				strlcpy(hbuf, "(invalid)", sizeof hbuf);
			(void)fprintf(stderr, "Trying %s...\n", hbuf);
			continue;
		}
		if (refused && timo.tv_sec <= 16) {
			(void)nanosleep(&timo, NULL);
			timo.tv_sec *= 2;
			r = res;
			refused = 0;
			continue;
		}
		(void)fprintf(stderr, "%s: %s\n", res->ai_canonname,
		    strerror(errno));
		sigprocmask(SIG_SETMASK, &oldmask, NULL);
		freeaddrinfo(res);
		return (-1);
	}
	/* given "af" can be PF_UNSPEC, we need the real af for "s" */
	af = r->ai_family;
	freeaddrinfo(res);
	if (fd2p == 0) {
		write(s, "", 1);
		lport = 0;
	} else {
		struct pollfd pfd[2];
		char num[8];
		int s2 = rresvport_af(&lport, af), s3;
		socklen_t len = sizeof(from);

		if (s2 < 0)
			goto bad;

		listen(s2, 1);
		(void)snprintf(num, sizeof(num), "%d", lport);
		if (write(s, num, strlen(num)+1) != strlen(num)+1) {
			(void)fprintf(stderr,
			    "rcmd: write (setting up stderr): %s\n",
			    strerror(errno));
			(void)close(s2);
			goto bad;
		}
again:
		pfd[0].fd = s;
		pfd[0].events = POLLIN;
		pfd[1].fd = s2;
		pfd[1].events = POLLIN;

		errno = 0;
		if (poll(pfd, 2, INFTIM) < 1 ||
		    (pfd[1].revents & (POLLIN|POLLHUP)) == 0) {
			if (errno != 0)
				(void)fprintf(stderr,
				    "rcmd: poll (setting up stderr): %s\n",
				    strerror(errno));
			else
				(void)fprintf(stderr,
				"poll: protocol failure in circuit setup\n");
			(void)close(s2);
			goto bad;
		}
		s3 = accept(s2, (struct sockaddr *)&from, &len);
		if (s3 < 0) {
			(void)fprintf(stderr,
			    "rcmd: accept: %s\n", strerror(errno));
			lport = 0;
			close(s2);
			goto bad;
		}

		/*
		 * XXX careful for ftp bounce attacks. If discovered, shut them
		 * down and check for the real auxiliary channel to connect.
		 */
		switch (from.ss_family) {
		case AF_INET:
		case AF_INET6:
			if (getnameinfo((struct sockaddr *)&from, len,
			    NULL, 0, num, sizeof(num), NI_NUMERICSERV) == 0 &&
			    atoi(num) != 20) {
				break;
			}
			close(s3);
			goto again;
		default:
			break;
		}
		(void)close(s2);

		*fd2p = s3;
		switch (from.ss_family) {
		case AF_INET:
		case AF_INET6:
			if (getnameinfo((struct sockaddr *)&from, len,
			    NULL, 0, num, sizeof(num), NI_NUMERICSERV) != 0 ||
			    (atoi(num) >= IPPORT_RESERVED ||
			     atoi(num) < IPPORT_RESERVED / 2)) {
				(void)fprintf(stderr,
				    "socket: protocol failure in circuit setup.\n");
				goto bad2;
			}
			break;
		default:
			break;
		}
	}
	(void)write(s, locuser, strlen(locuser)+1);
	(void)write(s, remuser, strlen(remuser)+1);
	(void)write(s, cmd, strlen(cmd)+1);
	if ((numread = read(s, &c, 1)) != 1) {
		(void)fprintf(stderr,
		    "rcmd: %s: %s\n", *ahost,
		    numread == -1 ? strerror(errno) : "Short read");
		goto bad2;
	}
	if (c != 0) {
		while (read(s, &c, 1) == 1) {
			(void)write(STDERR_FILENO, &c, 1);
			if (c == '\n')
				break;
		}
		goto bad2;
	}
	sigprocmask(SIG_SETMASK, &oldmask, NULL);
	return (s);
bad2:
	if (lport)
		(void)close(*fd2p);
bad:
	(void)close(s);
	sigprocmask(SIG_SETMASK, &oldmask, NULL);
	return (-1);
}
DEF_WEAK(rcmd_af);



Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/*
2			* Copyright (c) 1995, 1996, 1998 Theo de Raadt. All rights reserved.
3			* Copyright (c) 1983, 1993, 1994
4			* The Regents of the University of California. All rights reserved.
5			*
6			* Redistribution and use in source and binary forms, with or without
7			* modification, are permitted provided that the following conditions
8			* are met:
9			* 1. Redistributions of source code must retain the above copyright
10			* notice, this list of conditions and the following disclaimer.
11			* 2. Redistributions in binary form must reproduce the above copyright
12			* notice, this list of conditions and the following disclaimer in the
13			* documentation and/or other materials provided with the distribution.
14			* 3. Neither the name of the University nor the names of its contributors
15			* may be used to endorse or promote products derived from this software
16			* without specific prior written permission.
17			*
18			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28			* SUCH DAMAGE.
29			*/
30
31			#include <sys/socket.h>
32			#include <sys/stat.h>
33
34			#include <netinet/in.h>
35			#include <arpa/inet.h>
36
37			#include <signal.h>
38			#include <fcntl.h>
39			#include <netdb.h>
40			#include <unistd.h>
41			#include <limits.h>
42			#include <pwd.h>
43			#include <errno.h>
44			#include <stdio.h>
45			#include <ctype.h>
46			#include <string.h>
47			#include <syslog.h>
48			#include <time.h>
49			#include <stdlib.h>
50			#include <poll.h>
51
52			int
53			rcmd(char *ahost, int rport, const char locuser, const char *remuser,
54			const char cmd, int fd2p)
55			{
56			return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
57			}
58
59			int
60			rcmd_af(char *ahost, int porta, const char locuser, const char *remuser,
61			const char cmd, int fd2p, int af)
62			{
63			static char hbuf[HOST_NAME_MAX+1];
64			char pbuf[NI_MAXSERV];
65			struct addrinfo hints, res, r;
66			int error;
67			struct sockaddr_storage from;
68			sigset_t oldmask, mask;
69			pid_t pid;
70			int s, lport;
71			struct timespec timo;
72			char c, *p;
73			int refused;
74			in_port_t rport = porta;
75			int numread;
76
77			/* call rcmdsh() with specified remote shell if appropriate. */
78			if (!issetugid() && (p = getenv("RSH")) && *p) {
79			struct servent *sp = getservbyname("shell", "tcp");
80
81			if (sp && sp->s_port == rport)
82			return (rcmdsh(ahost, rport, locuser, remuser,
83			cmd, p));
84			}
85
86			/* use rsh(1) if non-root and remote port is shell. */
87			if (geteuid()) {
88			struct servent *sp = getservbyname("shell", "tcp");
89
90			if (sp && sp->s_port == rport)
91			return (rcmdsh(ahost, rport, locuser, remuser,
92			cmd, NULL));
93			}
94
95			pid = getpid();
96			snprintf(pbuf, sizeof(pbuf), "%u", ntohs(rport));
97			memset(&hints, 0, sizeof(hints));
98			hints.ai_family = af;
99			hints.ai_socktype = SOCK_STREAM;
100			hints.ai_flags = AI_CANONNAME;
101			error = getaddrinfo(*ahost, pbuf, &hints, &res);
102			if (error) {
103			(void)fprintf(stderr, "rcmd: %s: %s\n", *ahost,
104			gai_strerror(error));
105			return (-1);
106			}
107			if (res->ai_canonname) {
108			strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
109			*ahost = hbuf;
110			} else
111			; /XXX/
112
113			r = res;
114			refused = 0;
115			timespecclear(&timo);
116			sigemptyset(&mask);
117			sigaddset(&mask, SIGURG);
118			sigprocmask(SIG_BLOCK, &mask, &oldmask);
119			for (timo.tv_sec = 1, lport = IPPORT_RESERVED - 1;;) {
120			s = rresvport_af(&lport, r->ai_family);
121			if (s < 0) {
122			if (errno == EAGAIN)
123			(void)fprintf(stderr,
124			"rcmd: socket: All ports in use\n");
125			else
126			(void)fprintf(stderr, "rcmd: socket: %s\n",
127			strerror(errno));
128			if (r->ai_next) {
129			r = r->ai_next;
130			continue;
131			} else {
132			sigprocmask(SIG_SETMASK, &oldmask, NULL);
133			freeaddrinfo(res);
134			return (-1);
135			}
136			}
137			fcntl(s, F_SETOWN, pid);
138			if (connect(s, r->ai_addr, r->ai_addrlen) >= 0)
139			break;
140			(void)close(s);
141			if (errno == EADDRINUSE) {
142			lport--;
143			continue;
144			}
145			if (errno == ECONNREFUSED)
146			refused++;
147			if (r->ai_next) {
148			int oerrno = errno;
149			char hbuf[NI_MAXHOST];
150			const int niflags = NI_NUMERICHOST;
151
152			hbuf[0] = '\0';
153			if (getnameinfo(r->ai_addr, r->ai_addrlen,
154			hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
155			strlcpy(hbuf, "(invalid)", sizeof hbuf);
156			(void)fprintf(stderr, "connect to address %s: ", hbuf);
157			errno = oerrno;
158			perror(0);
159			r = r->ai_next;
160			hbuf[0] = '\0';
161			if (getnameinfo(r->ai_addr, r->ai_addrlen,
162			hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
163			strlcpy(hbuf, "(invalid)", sizeof hbuf);
164			(void)fprintf(stderr, "Trying %s...\n", hbuf);
165			continue;
166			}
167			if (refused && timo.tv_sec <= 16) {
168			(void)nanosleep(&timo, NULL);
169			timo.tv_sec *= 2;
170			r = res;
171			refused = 0;
172			continue;
173			}
174			(void)fprintf(stderr, "%s: %s\n", res->ai_canonname,
175			strerror(errno));
176			sigprocmask(SIG_SETMASK, &oldmask, NULL);
177			freeaddrinfo(res);
178			return (-1);
179			}
180			/* given "af" can be PF_UNSPEC, we need the real af for "s" */
181			af = r->ai_family;
182			freeaddrinfo(res);
183			if (fd2p == 0) {
184			write(s, "", 1);
185			lport = 0;
186			} else {
187			struct pollfd pfd[2];
188			char num[8];
189			int s2 = rresvport_af(&lport, af), s3;
190			socklen_t len = sizeof(from);
191
192			if (s2 < 0)
193			goto bad;
194
195			listen(s2, 1);
196			(void)snprintf(num, sizeof(num), "%d", lport);
197			if (write(s, num, strlen(num)+1) != strlen(num)+1) {
198			(void)fprintf(stderr,
199			"rcmd: write (setting up stderr): %s\n",
200			strerror(errno));
201			(void)close(s2);
202			goto bad;
203			}
204			again:
205			pfd[0].fd = s;
206			pfd[0].events = POLLIN;
207			pfd[1].fd = s2;
208			pfd[1].events = POLLIN;
209
210			errno = 0;
211			if (poll(pfd, 2, INFTIM) < 1 \|\|
212			(pfd[1].revents & (POLLIN\|POLLHUP)) == 0) {
213			if (errno != 0)
214			(void)fprintf(stderr,
215			"rcmd: poll (setting up stderr): %s\n",
216			strerror(errno));
217			else
218			(void)fprintf(stderr,
219			"poll: protocol failure in circuit setup\n");
220			(void)close(s2);
221			goto bad;
222			}
223			s3 = accept(s2, (struct sockaddr *)&from, &len);
224			if (s3 < 0) {
225			(void)fprintf(stderr,
226			"rcmd: accept: %s\n", strerror(errno));
227			lport = 0;
228			close(s2);
229			goto bad;
230			}
231
232			/*
233			* XXX careful for ftp bounce attacks. If discovered, shut them
234			* down and check for the real auxiliary channel to connect.
235			*/
236			switch (from.ss_family) {
237			case AF_INET:
238			case AF_INET6:
239			if (getnameinfo((struct sockaddr *)&from, len,
240			NULL, 0, num, sizeof(num), NI_NUMERICSERV) == 0 &&
241			atoi(num) != 20) {
242			break;
243			}
244			close(s3);
245			goto again;
246			default:
247			break;
248			}
249			(void)close(s2);
250
251			*fd2p = s3;
252			switch (from.ss_family) {
253			case AF_INET:
254			case AF_INET6:
255			if (getnameinfo((struct sockaddr *)&from, len,
256			NULL, 0, num, sizeof(num), NI_NUMERICSERV) != 0 \|\|
257			(atoi(num) >= IPPORT_RESERVED \|\|
258			atoi(num) < IPPORT_RESERVED / 2)) {
259			(void)fprintf(stderr,
260			"socket: protocol failure in circuit setup.\n");
261			goto bad2;
262			}
263			break;
264			default:
265			break;
266			}
267			}
268			(void)write(s, locuser, strlen(locuser)+1);
269			(void)write(s, remuser, strlen(remuser)+1);
270			(void)write(s, cmd, strlen(cmd)+1);
271			if ((numread = read(s, &c, 1)) != 1) {
272			(void)fprintf(stderr,
273			"rcmd: %s: %s\n", *ahost,
274			numread == -1 ? strerror(errno) : "Short read");
275			goto bad2;
276			}
277			if (c != 0) {
278			while (read(s, &c, 1) == 1) {
279			(void)write(STDERR_FILENO, &c, 1);
280			if (c == '\n')
281			break;
282			}
283			goto bad2;
284			}
285			sigprocmask(SIG_SETMASK, &oldmask, NULL);
286			return (s);
287			bad2:
288			if (lport)
289			(void)close(*fd2p);
290			bad:
291			(void)close(s);
292			sigprocmask(SIG_SETMASK, &oldmask, NULL);
293			return (-1);
294			}
295			DEF_WEAK(rcmd_af);
296