1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)exec.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "namespace.h" 41 #include <sys/param.h> 42 #include <sys/types.h> 43 #include <sys/stat.h> 44 #include <errno.h> 45 #include <unistd.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include <stdio.h> 49 #include <paths.h> 50 51 #include <stdarg.h> 52 #include "un-namespace.h" 53 54 extern char **environ; 55 56 int 57 execl(const char *name, const char *arg, ...) 58 { 59 va_list ap; 60 char **argv; 61 int n; 62 63 va_start(ap, arg); 64 n = 1; 65 while (va_arg(ap, char *) != NULL) 66 n++; 67 va_end(ap); 68 argv = alloca((n + 1) * sizeof(*argv)); 69 if (argv == NULL) { 70 errno = ENOMEM; 71 return (-1); 72 } 73 va_start(ap, arg); 74 n = 1; 75 argv[0] = (char *)arg; 76 while ((argv[n] = va_arg(ap, char *)) != NULL) 77 n++; 78 va_end(ap); 79 return (_execve(name, argv, environ)); 80 } 81 82 int 83 execle(const char *name, const char *arg, ...) 84 { 85 va_list ap; 86 char **argv, **envp; 87 int n; 88 89 va_start(ap, arg); 90 n = 1; 91 while (va_arg(ap, char *) != NULL) 92 n++; 93 va_end(ap); 94 argv = alloca((n + 1) * sizeof(*argv)); 95 if (argv == NULL) { 96 errno = ENOMEM; 97 return (-1); 98 } 99 va_start(ap, arg); 100 n = 1; 101 argv[0] = (char *)arg; 102 while ((argv[n] = va_arg(ap, char *)) != NULL) 103 n++; 104 envp = va_arg(ap, char **); 105 va_end(ap); 106 return (_execve(name, argv, envp)); 107 } 108 109 int 110 execlp(const char *name, const char *arg, ...) 111 { 112 va_list ap; 113 int sverrno; 114 char **argv; 115 int n; 116 117 va_start(ap, arg); 118 n = 1; 119 while (va_arg(ap, char *) != NULL) 120 n++; 121 va_end(ap); 122 argv = alloca((n + 1) * sizeof(*argv)); 123 if (argv == NULL) { 124 errno = ENOMEM; 125 return (-1); 126 } 127 va_start(ap, arg); 128 n = 1; 129 argv[0] = (char *)arg; 130 while ((argv[n] = va_arg(ap, char *)) != NULL) 131 n++; 132 va_end(ap); 133 return (execvp(name, argv)); 134 } 135 136 int 137 execv(name, argv) 138 const char *name; 139 char * const *argv; 140 { 141 (void)_execve(name, argv, environ); 142 return (-1); 143 } 144 145 int 146 execvp(name, argv) 147 const char *name; 148 char * const *argv; 149 { 150 char **memp; 151 int cnt, lp, ln; 152 char *p; 153 int eacces, save_errno; 154 char *bp, *cur, *path, buf[MAXPATHLEN]; 155 struct stat sb; 156 157 eacces = 0; 158 159 /* If it's an absolute or relative path name, it's easy. */ 160 if (index(name, '/')) { 161 bp = (char *)name; 162 cur = path = NULL; 163 goto retry; 164 } 165 bp = buf; 166 167 /* If it's an empty path name, fail in the usual POSIX way. */ 168 if (*name == '\0') { 169 errno = ENOENT; 170 return (-1); 171 } 172 173 /* Get the path we're searching. */ 174 if (!(path = getenv("PATH"))) 175 path = _PATH_DEFPATH; 176 cur = alloca(strlen(path) + 1); 177 if (cur == NULL) { 178 errno = ENOMEM; 179 return (-1); 180 } 181 strcpy(cur, path); 182 path = cur; 183 while ( (p = strsep(&cur, ":")) ) { 184 /* 185 * It's a SHELL path -- double, leading and trailing colons 186 * mean the current directory. 187 */ 188 if (!*p) { 189 p = "."; 190 lp = 1; 191 } else 192 lp = strlen(p); 193 ln = strlen(name); 194 195 /* 196 * If the path is too long complain. This is a possible 197 * security issue; given a way to make the path too long 198 * the user may execute the wrong program. 199 */ 200 if (lp + ln + 2 > sizeof(buf)) { 201 (void)_write(STDERR_FILENO, "execvp: ", 8); 202 (void)_write(STDERR_FILENO, p, lp); 203 (void)_write(STDERR_FILENO, ": path too long\n", 204 16); 205 continue; 206 } 207 bcopy(p, buf, lp); 208 buf[lp] = '/'; 209 bcopy(name, buf + lp + 1, ln); 210 buf[lp + ln + 1] = '\0'; 211 212 retry: (void)_execve(bp, argv, environ); 213 switch(errno) { 214 case E2BIG: 215 goto done; 216 case ELOOP: 217 case ENAMETOOLONG: 218 case ENOENT: 219 break; 220 case ENOEXEC: 221 for (cnt = 0; argv[cnt]; ++cnt) 222 ; 223 memp = alloca((cnt + 2) * sizeof(char *)); 224 if (memp == NULL) { 225 /* errno = ENOMEM; XXX override ENOEXEC? */ 226 goto done; 227 } 228 memp[0] = "sh"; 229 memp[1] = bp; 230 bcopy(argv + 1, memp + 2, cnt * sizeof(char *)); 231 (void)_execve(_PATH_BSHELL, memp, environ); 232 goto done; 233 case ENOMEM: 234 goto done; 235 case ENOTDIR: 236 break; 237 case ETXTBSY: 238 /* 239 * We used to retry here, but sh(1) doesn't. 240 */ 241 goto done; 242 default: 243 /* 244 * EACCES may be for an inaccessible directory or 245 * a non-executable file. Call stat() to decide 246 * which. This also handles ambiguities for EFAULT 247 * and EIO, and undocumented errors like ESTALE. 248 * We hope that the race for a stat() is unimportant. 249 */ 250 save_errno = errno; 251 if (stat(bp, &sb) != 0) 252 break; 253 if (save_errno == EACCES) { 254 eacces = 1; 255 continue; 256 } 257 errno = save_errno; 258 goto done; 259 } 260 } 261 if (eacces) 262 errno = EACCES; 263 else 264 errno = ENOENT; 265 done: 266 return (-1); 267 } 268