1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
30*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
31*0Sstevel@tonic-gate 
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  *	execlp(name, arg,...,0)	(like execl, but does path search)
35*0Sstevel@tonic-gate  *	execvp(name, argv)	(like execv, but does path search)
36*0Sstevel@tonic-gate  */
37*0Sstevel@tonic-gate #pragma weak execlp = _execlp
38*0Sstevel@tonic-gate #pragma weak execvp = _execvp
39*0Sstevel@tonic-gate #include "synonyms.h"
40*0Sstevel@tonic-gate #include <sys/types.h>
41*0Sstevel@tonic-gate #include <unistd.h>
42*0Sstevel@tonic-gate #include <string.h>
43*0Sstevel@tonic-gate #include <alloca.h>
44*0Sstevel@tonic-gate #include <errno.h>
45*0Sstevel@tonic-gate #include <limits.h>
46*0Sstevel@tonic-gate #include <stdarg.h>
47*0Sstevel@tonic-gate #include <stdlib.h>
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate static const char *execat(const char *, const char *, char *);
50*0Sstevel@tonic-gate 
51*0Sstevel@tonic-gate extern  int __xpg4;	/* defined in xpg4.c; 0 if not xpg4-compiled program */
52*0Sstevel@tonic-gate 
53*0Sstevel@tonic-gate /*VARARGS1*/
54*0Sstevel@tonic-gate int
55*0Sstevel@tonic-gate execlp(const char *name, const char *arg0, ...)
56*0Sstevel@tonic-gate {
57*0Sstevel@tonic-gate 	char **argp;
58*0Sstevel@tonic-gate 	va_list args;
59*0Sstevel@tonic-gate 	char **argvec;
60*0Sstevel@tonic-gate 	int err;
61*0Sstevel@tonic-gate 	int nargs = 0;
62*0Sstevel@tonic-gate 	char *nextarg;
63*0Sstevel@tonic-gate 
64*0Sstevel@tonic-gate 	/*
65*0Sstevel@tonic-gate 	 * count the number of arguments in the variable argument list
66*0Sstevel@tonic-gate 	 * and allocate an argument vector for them on the stack,
67*0Sstevel@tonic-gate 	 * adding space for a terminating null pointer at the end
68*0Sstevel@tonic-gate 	 * and one additional space for argv[0] which is no longer
69*0Sstevel@tonic-gate 	 * counted by the varargs loop.
70*0Sstevel@tonic-gate 	 */
71*0Sstevel@tonic-gate 
72*0Sstevel@tonic-gate 	va_start(args, arg0);
73*0Sstevel@tonic-gate 
74*0Sstevel@tonic-gate 	while (va_arg(args, char *) != (char *)0)
75*0Sstevel@tonic-gate 		nargs++;
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate 	va_end(args);
78*0Sstevel@tonic-gate 
79*0Sstevel@tonic-gate 	/*
80*0Sstevel@tonic-gate 	 * load the arguments in the variable argument list
81*0Sstevel@tonic-gate 	 * into the argument vector and add the terminating null pointer
82*0Sstevel@tonic-gate 	 */
83*0Sstevel@tonic-gate 
84*0Sstevel@tonic-gate 	va_start(args, arg0);
85*0Sstevel@tonic-gate 	/* workaround for bugid 1242839 */
86*0Sstevel@tonic-gate 	argvec = alloca((size_t)((nargs + 2) * sizeof (char *)));
87*0Sstevel@tonic-gate 	nextarg = va_arg(args, char *);
88*0Sstevel@tonic-gate 	argp = argvec;
89*0Sstevel@tonic-gate 	*argp++ = (char *)arg0;
90*0Sstevel@tonic-gate 	while (nargs-- && nextarg != (char *)0) {
91*0Sstevel@tonic-gate 		*argp = nextarg;
92*0Sstevel@tonic-gate 		argp++;
93*0Sstevel@tonic-gate 		nextarg = va_arg(args, char *);
94*0Sstevel@tonic-gate 	}
95*0Sstevel@tonic-gate 	va_end(args);
96*0Sstevel@tonic-gate 	*argp = (char *)0;
97*0Sstevel@tonic-gate 
98*0Sstevel@tonic-gate 	/*
99*0Sstevel@tonic-gate 	 * call execvp()
100*0Sstevel@tonic-gate 	 */
101*0Sstevel@tonic-gate 
102*0Sstevel@tonic-gate 	err = execvp(name, argvec);
103*0Sstevel@tonic-gate 	return (err);
104*0Sstevel@tonic-gate }
105*0Sstevel@tonic-gate 
106*0Sstevel@tonic-gate int
107*0Sstevel@tonic-gate execvp(const char *name, char *const *argv)
108*0Sstevel@tonic-gate {
109*0Sstevel@tonic-gate 	const char	*pathstr;
110*0Sstevel@tonic-gate 	char	fname[PATH_MAX+2];
111*0Sstevel@tonic-gate 	char	*newargs[256];
112*0Sstevel@tonic-gate 	int	i;
113*0Sstevel@tonic-gate 	const char *cp;
114*0Sstevel@tonic-gate 	unsigned etxtbsy = 1;
115*0Sstevel@tonic-gate 	int eacces = 0;
116*0Sstevel@tonic-gate 	char *shpath;
117*0Sstevel@tonic-gate 	static const char *sun_path = "/bin/sh";
118*0Sstevel@tonic-gate 	static const char *xpg4_path = "/usr/xpg4/bin/sh";
119*0Sstevel@tonic-gate 	static const char *shell = "sh";
120*0Sstevel@tonic-gate 
121*0Sstevel@tonic-gate 	if (*name == '\0') {
122*0Sstevel@tonic-gate 		errno = ENOENT;
123*0Sstevel@tonic-gate 		return (-1);
124*0Sstevel@tonic-gate 	}
125*0Sstevel@tonic-gate 	if ((pathstr = getenv("PATH")) == NULL) {
126*0Sstevel@tonic-gate 		/*
127*0Sstevel@tonic-gate 		 * XPG4:  pathstr is equivalent to CSPATH, except that
128*0Sstevel@tonic-gate 		 * :/usr/sbin is appended when root, and pathstr must end
129*0Sstevel@tonic-gate 		 * with a colon when not root.  Keep these paths in sync
130*0Sstevel@tonic-gate 		 * with CSPATH in confstr.c.  Note that pathstr must end
131*0Sstevel@tonic-gate 		 * with a colon when not root so that when name doesn't
132*0Sstevel@tonic-gate 		 * contain '/', the last call to execat() will result in an
133*0Sstevel@tonic-gate 		 * attempt to execv name from the current directory.
134*0Sstevel@tonic-gate 		 */
135*0Sstevel@tonic-gate 		if (geteuid() == 0 || getuid() == 0) {
136*0Sstevel@tonic-gate 			if (__xpg4 == 0) {	/* not XPG4 */
137*0Sstevel@tonic-gate 				pathstr = "/usr/sbin:/usr/ccs/bin:/usr/bin";
138*0Sstevel@tonic-gate 			} else {		/* XPG4 (CSPATH + /usr/sbin) */
139*0Sstevel@tonic-gate 		pathstr = "/usr/xpg4/bin:/usr/ccs/bin:/usr/bin:"
140*0Sstevel@tonic-gate 				"/opt/SUNWspro/bin:/usr/sbin";
141*0Sstevel@tonic-gate 			}
142*0Sstevel@tonic-gate 		} else {
143*0Sstevel@tonic-gate 			if (__xpg4 == 0) {	/* not XPG4 */
144*0Sstevel@tonic-gate 				pathstr = "/usr/ccs/bin:/usr/bin:";
145*0Sstevel@tonic-gate 			} else {		/* XPG4 (CSPATH) */
146*0Sstevel@tonic-gate 				pathstr = "/usr/xpg4/bin:/usr/ccs/bin:"
147*0Sstevel@tonic-gate 				    "/usr/bin:/opt/SUNWspro/bin:";
148*0Sstevel@tonic-gate 			}
149*0Sstevel@tonic-gate 		}
150*0Sstevel@tonic-gate 	}
151*0Sstevel@tonic-gate 	cp = strchr(name, '/')? (const char *)"": pathstr;
152*0Sstevel@tonic-gate 
153*0Sstevel@tonic-gate 	do {
154*0Sstevel@tonic-gate 		cp = execat(cp, name, fname);
155*0Sstevel@tonic-gate 	retry:
156*0Sstevel@tonic-gate 		/*
157*0Sstevel@tonic-gate 		 * 4025035 and 4038378
158*0Sstevel@tonic-gate 		 * if a filename begins with a "-" prepend "./" so that
159*0Sstevel@tonic-gate 		 * the shell can't interpret it as an option
160*0Sstevel@tonic-gate 		 */
161*0Sstevel@tonic-gate 		if (*fname == '-') {
162*0Sstevel@tonic-gate 			size_t size = strlen(fname) + 1;
163*0Sstevel@tonic-gate 			if ((size + 2) > sizeof (fname)) {
164*0Sstevel@tonic-gate 				errno = E2BIG;
165*0Sstevel@tonic-gate 				return (-1);
166*0Sstevel@tonic-gate 			}
167*0Sstevel@tonic-gate 			(void) memmove(fname + 2, fname, size);
168*0Sstevel@tonic-gate 			fname[0] = '.';
169*0Sstevel@tonic-gate 			fname[1] = '/';
170*0Sstevel@tonic-gate 		}
171*0Sstevel@tonic-gate 		(void) execv(fname, argv);
172*0Sstevel@tonic-gate 		switch (errno) {
173*0Sstevel@tonic-gate 		case ENOEXEC:
174*0Sstevel@tonic-gate 			if (__xpg4 == 0) {	/* not XPG4 */
175*0Sstevel@tonic-gate 				shpath = (char *)sun_path;
176*0Sstevel@tonic-gate 			} else {		/* XPG4 */
177*0Sstevel@tonic-gate 				shpath = (char *)xpg4_path;
178*0Sstevel@tonic-gate 			}
179*0Sstevel@tonic-gate 			newargs[0] = (char *)shell;
180*0Sstevel@tonic-gate 			newargs[1] = fname;
181*0Sstevel@tonic-gate 			for (i = 1; (newargs[i + 1] = argv[i]) != NULL; ++i) {
182*0Sstevel@tonic-gate 				if (i >= 254) {
183*0Sstevel@tonic-gate 					errno = E2BIG;
184*0Sstevel@tonic-gate 					return (-1);
185*0Sstevel@tonic-gate 				}
186*0Sstevel@tonic-gate 			}
187*0Sstevel@tonic-gate 			(void) execv((const char *)shpath, newargs);
188*0Sstevel@tonic-gate 			return (-1);
189*0Sstevel@tonic-gate 		case ETXTBSY:
190*0Sstevel@tonic-gate 			if (++etxtbsy > 5)
191*0Sstevel@tonic-gate 				return (-1);
192*0Sstevel@tonic-gate 			(void) sleep(etxtbsy);
193*0Sstevel@tonic-gate 			goto retry;
194*0Sstevel@tonic-gate 		case EACCES:
195*0Sstevel@tonic-gate 			++eacces;
196*0Sstevel@tonic-gate 			break;
197*0Sstevel@tonic-gate 		case ENOMEM:
198*0Sstevel@tonic-gate 		case E2BIG:
199*0Sstevel@tonic-gate 		case EFAULT:
200*0Sstevel@tonic-gate 			return (-1);
201*0Sstevel@tonic-gate 		}
202*0Sstevel@tonic-gate 	} while (cp);
203*0Sstevel@tonic-gate 	if (eacces)
204*0Sstevel@tonic-gate 		errno = EACCES;
205*0Sstevel@tonic-gate 	return (-1);
206*0Sstevel@tonic-gate }
207*0Sstevel@tonic-gate 
208*0Sstevel@tonic-gate static const char *
209*0Sstevel@tonic-gate execat(const char *s1, const char *s2, char *si)
210*0Sstevel@tonic-gate {
211*0Sstevel@tonic-gate 	char	*s;
212*0Sstevel@tonic-gate 	int cnt = PATH_MAX + 1; /* number of characters in s2 */
213*0Sstevel@tonic-gate 
214*0Sstevel@tonic-gate 	s = si;
215*0Sstevel@tonic-gate 	while (*s1 && *s1 != ':') {
216*0Sstevel@tonic-gate 		if (cnt > 0) {
217*0Sstevel@tonic-gate 			*s++ = *s1++;
218*0Sstevel@tonic-gate 			cnt--;
219*0Sstevel@tonic-gate 		} else
220*0Sstevel@tonic-gate 			s1++;
221*0Sstevel@tonic-gate 	}
222*0Sstevel@tonic-gate 	if (si != s && cnt > 0) {
223*0Sstevel@tonic-gate 		*s++ = '/';
224*0Sstevel@tonic-gate 		cnt--;
225*0Sstevel@tonic-gate 	}
226*0Sstevel@tonic-gate 	while (*s2 && cnt > 0) {
227*0Sstevel@tonic-gate 		*s++ = *s2++;
228*0Sstevel@tonic-gate 		cnt--;
229*0Sstevel@tonic-gate 	}
230*0Sstevel@tonic-gate 	*s = '\0';
231*0Sstevel@tonic-gate 	return (*s1 ? ++s1: 0);
232*0Sstevel@tonic-gate }
233