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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/net/rcmdsh.c	Lines:	0	89	0.0 %
Date:	2017-11-13	Branches:	0	50	0.0 %


/*	$OpenBSD: rcmdsh.c,v 1.19 2016/05/28 15:46:00 millert Exp $	*/

/*
 * Copyright (c) 2001, MagniComp
 * 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 MagniComp 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 COPYRIGHT HOLDERS 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.
 */

/*
 * This is an rcmd() replacement originally by
 * Chris Siebenmann <cks@utcc.utoronto.ca>.
 */

#include      <sys/types.h>
#include      <sys/socket.h>
#include      <sys/wait.h>
#include      <signal.h>
#include      <errno.h>
#include      <limits.h>
#include      <netdb.h>
#include      <stdio.h>
#include      <stdlib.h>
#include      <string.h>
#include      <pwd.h>
#include      <paths.h>
#include      <unistd.h>

/*
 * This is a replacement rcmd() function that uses the ssh(1)
 * program in place of a direct rcmd(3) function call so as to
 * avoid having to be root.  Note that rport is ignored.
 */
int
rcmdsh(char **ahost, int rport, const char *locuser, const char *remuser,
    const char *cmd, char *rshprog)
{
	static char hbuf[HOST_NAME_MAX+1];
	struct addrinfo hint, *res;
	int sp[2];
	pid_t cpid;
	char *p, pwbuf[_PW_BUF_LEN];
	struct passwd pwstore, *pw = NULL;

	/* What rsh/shell to use. */
	if (rshprog == NULL)
		rshprog = _PATH_RSH;

	/* locuser must exist on this host. */
	getpwnam_r(locuser, &pwstore, pwbuf, sizeof(pwbuf), &pw);
	if (pw == NULL) {
		(void) fprintf(stderr, "rcmdsh: unknown user: %s\n", locuser);
		return(-1);
	}

	/* Validate remote hostname. */
	if (strcmp(*ahost, "localhost") != 0) {
		memset(&hint, 0, sizeof(hint));
		hint.ai_family = PF_UNSPEC;
		hint.ai_flags = AI_CANONNAME;
		if (getaddrinfo(*ahost, NULL, &hint, &res) == 0) {
			if (res->ai_canonname) {
				strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
				*ahost = hbuf;
			}
			freeaddrinfo(res);
		}
	}

	/* Get a socketpair we'll use for stdin and stdout. */
	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, sp) < 0) {
		perror("rcmdsh: socketpair");
		return(-1);
	}

	cpid = fork();
	if (cpid < 0) {
		perror("rcmdsh: fork failed");
		return(-1);
	} else if (cpid == 0) {
		/*
		 * Child.  We use sp[1] to be stdin/stdout, and close sp[0].
		 */
		(void) close(sp[0]);
		if (dup2(sp[1], 0) < 0 || dup2(0, 1) < 0) {
			perror("rcmdsh: dup2 failed");
			_exit(255);
		}
		/* Fork again to lose parent. */
		cpid = fork();
		if (cpid < 0) {
			perror("rcmdsh: fork to lose parent failed");
			_exit(255);
		}
		if (cpid > 0)
			_exit(0);

		/* In grandchild here.  Become local user for rshprog. */
		if (setuid(pw->pw_uid)) {
			(void) fprintf(stderr, "rcmdsh: setuid(%u): %s\n",
				       pw->pw_uid, strerror(errno));
			_exit(255);
		}

		/*
		 * If remote host is "localhost" and local and remote user
		 * are the same, avoid running remote shell for efficiency.
		 */
		if (!strcmp(*ahost, "localhost") && !strcmp(locuser, remuser)) {
			char *argv[4];
			if (pw->pw_shell[0] == '\0')
				rshprog = _PATH_BSHELL;
			else
				rshprog = pw->pw_shell;
			p = strrchr(rshprog, '/');
			argv[0] = p ? p + 1 : rshprog;
			argv[1] = "-c";
			argv[2] = (char *)cmd;
			argv[3] = NULL;
			execvp(rshprog, argv);
		} else if ((p = strchr(rshprog, ' ')) == NULL) {
			/* simple case */
			char *argv[6];
			p = strrchr(rshprog, '/');
			argv[0] = p ? p + 1 : rshprog;
			argv[1] = "-l";
			argv[2] = (char *)remuser;
			argv[3] = *ahost;
			argv[4] = (char *)cmd;
			argv[5] = NULL;
			execvp(rshprog, argv);
		} else {
			/* must pull args out of rshprog and dyn alloc argv */
			char **argv, **ap;
			int n;
			for (n = 7; (p = strchr(++p, ' ')) != NULL; n++)
				continue;
			rshprog = strdup(rshprog);
			ap = argv = calloc(sizeof(char *), n);
			if (rshprog == NULL || argv == NULL) {
				perror("rcmdsh");
				_exit(255);
			}
			while ((p = strsep(&rshprog, " ")) != NULL) {
				if (*p == '\0')
					continue;
				*ap++ = p;
			}
			if (ap != argv)		/* all spaces?!? */
				rshprog = argv[0];
			if ((p = strrchr(argv[0], '/')) != NULL)
				argv[0] = p + 1;
			*ap++ = "-l";
			*ap++ = (char *)remuser;
			*ap++ = *ahost;
			*ap++ = (char *)cmd;
			*ap++ = NULL;
			execvp(rshprog, argv);
		}
		(void) fprintf(stderr, "rcmdsh: execvp %s failed: %s\n",
			       rshprog, strerror(errno));
		_exit(255);
	} else {
		/* Parent. close sp[1], return sp[0]. */
		(void) close(sp[1]);
		/* Reap child. */
		while (waitpid(cpid, NULL, 0) == -1 && errno == EINTR)
			;
		return(sp[0]);
	}
	/* NOTREACHED */
}
DEF_WEAK(rcmdsh);


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: rcmdsh.c,v 1.19 2016/05/28 15:46:00 millert Exp $ */
2
3			/*
4			* Copyright (c) 2001, MagniComp
5			* 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
14			* the documentation and/or other materials provided with the distribution.
15			* 3. Neither the name of the MagniComp nor the names of its contributors may
16			* 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 COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20			* AND 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 FOR
23			* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25			* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
26			* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27			* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
28			* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29			*/
30
31			/*
32			* This is an rcmd() replacement originally by
33			* Chris Siebenmann <cks@utcc.utoronto.ca>.
34			*/
35
36			#include <sys/types.h>
37			#include <sys/socket.h>
38			#include <sys/wait.h>
39			#include <signal.h>
40			#include <errno.h>
41			#include <limits.h>
42			#include <netdb.h>
43			#include <stdio.h>
44			#include <stdlib.h>
45			#include <string.h>
46			#include <pwd.h>
47			#include <paths.h>
48			#include <unistd.h>
49
50			/*
51			* This is a replacement rcmd() function that uses the ssh(1)
52			* program in place of a direct rcmd(3) function call so as to
53			* avoid having to be root. Note that rport is ignored.
54			*/
55			int
56			rcmdsh(char *ahost, int rport, const char locuser, const char *remuser,
57			const char cmd, char rshprog)
58			{
59			static char hbuf[HOST_NAME_MAX+1];
60			struct addrinfo hint, *res;
61			int sp[2];
62			pid_t cpid;
63			char *p, pwbuf[_PW_BUF_LEN];
64			struct passwd pwstore, *pw = NULL;
65
66			/* What rsh/shell to use. */
67			if (rshprog == NULL)
68			rshprog = _PATH_RSH;
69
70			/* locuser must exist on this host. */
71			getpwnam_r(locuser, &pwstore, pwbuf, sizeof(pwbuf), &pw);
72			if (pw == NULL) {
73			(void) fprintf(stderr, "rcmdsh: unknown user: %s\n", locuser);
74			return(-1);
75			}
76
77			/* Validate remote hostname. */
78			if (strcmp(*ahost, "localhost") != 0) {
79			memset(&hint, 0, sizeof(hint));
80			hint.ai_family = PF_UNSPEC;
81			hint.ai_flags = AI_CANONNAME;
82			if (getaddrinfo(*ahost, NULL, &hint, &res) == 0) {
83			if (res->ai_canonname) {
84			strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
85			*ahost = hbuf;
86			}
87			freeaddrinfo(res);
88			}
89			}
90
91			/* Get a socketpair we'll use for stdin and stdout. */
92			if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, sp) < 0) {
93			perror("rcmdsh: socketpair");
94			return(-1);
95			}
96
97			cpid = fork();
98			if (cpid < 0) {
99			perror("rcmdsh: fork failed");
100			return(-1);
101			} else if (cpid == 0) {
102			/*
103			* Child. We use sp[1] to be stdin/stdout, and close sp[0].
104			*/
105			(void) close(sp[0]);
106			if (dup2(sp[1], 0) < 0 \|\| dup2(0, 1) < 0) {
107			perror("rcmdsh: dup2 failed");
108			_exit(255);
109			}
110			/* Fork again to lose parent. */
111			cpid = fork();
112			if (cpid < 0) {
113			perror("rcmdsh: fork to lose parent failed");
114			_exit(255);
115			}
116			if (cpid > 0)
117			_exit(0);
118
119			/* In grandchild here. Become local user for rshprog. */
120			if (setuid(pw->pw_uid)) {
121			(void) fprintf(stderr, "rcmdsh: setuid(%u): %s\n",
122			pw->pw_uid, strerror(errno));
123			_exit(255);
124			}
125
126			/*
127			* If remote host is "localhost" and local and remote user
128			* are the same, avoid running remote shell for efficiency.
129			*/
130			if (!strcmp(*ahost, "localhost") && !strcmp(locuser, remuser)) {
131			char *argv[4];
132			if (pw->pw_shell[0] == '\0')
133			rshprog = _PATH_BSHELL;
134			else
135			rshprog = pw->pw_shell;
136			p = strrchr(rshprog, '/');
137			argv[0] = p ? p + 1 : rshprog;
138			argv[1] = "-c";
139			argv[2] = (char *)cmd;
140			argv[3] = NULL;
141			execvp(rshprog, argv);
142			} else if ((p = strchr(rshprog, ' ')) == NULL) {
143			/* simple case */
144			char *argv[6];
145			p = strrchr(rshprog, '/');
146			argv[0] = p ? p + 1 : rshprog;
147			argv[1] = "-l";
148			argv[2] = (char *)remuser;
149			argv[3] = *ahost;
150			argv[4] = (char *)cmd;
151			argv[5] = NULL;
152			execvp(rshprog, argv);
153			} else {
154			/* must pull args out of rshprog and dyn alloc argv */
155			char argv, ap;
156			int n;
157			for (n = 7; (p = strchr(++p, ' ')) != NULL; n++)
158			continue;
159			rshprog = strdup(rshprog);
160			ap = argv = calloc(sizeof(char *), n);
161			if (rshprog == NULL \|\| argv == NULL) {
162			perror("rcmdsh");
163			_exit(255);
164			}
165			while ((p = strsep(&rshprog, " ")) != NULL) {
166			if (*p == '\0')
167			continue;
168			*ap++ = p;
169			}
170			if (ap != argv) /* all spaces?!? */
171			rshprog = argv[0];
172			if ((p = strrchr(argv[0], '/')) != NULL)
173			argv[0] = p + 1;
174			*ap++ = "-l";
175			ap++ = (char )remuser;
176			ap++ = ahost;
177			ap++ = (char )cmd;
178			*ap++ = NULL;
179			execvp(rshprog, argv);
180			}
181			(void) fprintf(stderr, "rcmdsh: execvp %s failed: %s\n",
182			rshprog, strerror(errno));
183			_exit(255);
184			} else {
185			/* Parent. close sp[1], return sp[0]. */
186			(void) close(sp[1]);
187			/* Reap child. */
188			while (waitpid(cpid, NULL, 0) == -1 && errno == EINTR)
189			;
190			return(sp[0]);
191			}
192			/* NOTREACHED */
193			}
194			DEF_WEAK(rcmdsh);