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 * $FreeBSD$ 34 */ 35 36 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)exec.c 8.1 (Berkeley) 6/4/93"; 39 #endif 40 static const char rcsid[] = 41 "$FreeBSD$"; 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include "namespace.h" 45 #include <sys/param.h> 46 #include <sys/types.h> 47 #include <sys/stat.h> 48 #include <errno.h> 49 #include <unistd.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <stdio.h> 53 #include <paths.h> 54 55 #if __STDC__ 56 #include <stdarg.h> 57 #else 58 #include <varargs.h> 59 #endif 60 #include "un-namespace.h" 61 62 extern char **environ; 63 64 int 65 #if __STDC__ 66 execl(const char *name, const char *arg, ...) 67 #else 68 execl(name, arg, va_alist) 69 const char *name; 70 const char *arg; 71 va_dcl 72 #endif 73 { 74 va_list ap; 75 char **argv; 76 int n; 77 78 #if __STDC__ 79 va_start(ap, arg); 80 #else 81 va_start(ap); 82 #endif 83 n = 1; 84 while (va_arg(ap, char *) != NULL) 85 n++; 86 va_end(ap); 87 argv = alloca((n + 1) * sizeof(*argv)); 88 if (argv == NULL) { 89 errno = ENOMEM; 90 return (-1); 91 } 92 #if __STDC__ 93 va_start(ap, arg); 94 #else 95 va_start(ap); 96 #endif 97 n = 1; 98 argv[0] = (char *)arg; 99 while ((argv[n] = va_arg(ap, char *)) != NULL) 100 n++; 101 va_end(ap); 102 return (_execve(name, argv, environ)); 103 } 104 105 int 106 #if __STDC__ 107 execle(const char *name, const char *arg, ...) 108 #else 109 execle(name, arg, va_alist) 110 const char *name; 111 const char *arg; 112 va_dcl 113 #endif 114 { 115 va_list ap; 116 char **argv, **envp; 117 int n; 118 119 #if __STDC__ 120 va_start(ap, arg); 121 #else 122 va_start(ap); 123 #endif 124 n = 1; 125 while (va_arg(ap, char *) != NULL) 126 n++; 127 va_end(ap); 128 argv = alloca((n + 1) * sizeof(*argv)); 129 if (argv == NULL) { 130 errno = ENOMEM; 131 return (-1); 132 } 133 #if __STDC__ 134 va_start(ap, arg); 135 #else 136 va_start(ap); 137 #endif 138 n = 1; 139 argv[0] = (char *)arg; 140 while ((argv[n] = va_arg(ap, char *)) != NULL) 141 n++; 142 envp = va_arg(ap, char **); 143 va_end(ap); 144 return (_execve(name, argv, envp)); 145 } 146 147 int 148 #if __STDC__ 149 execlp(const char *name, const char *arg, ...) 150 #else 151 execlp(name, arg, va_alist) 152 const char *name; 153 const char *arg; 154 va_dcl 155 #endif 156 { 157 va_list ap; 158 int sverrno; 159 char **argv; 160 int n; 161 162 #if __STDC__ 163 va_start(ap, arg); 164 #else 165 va_start(ap); 166 #endif 167 n = 1; 168 while (va_arg(ap, char *) != NULL) 169 n++; 170 va_end(ap); 171 argv = alloca((n + 1) * sizeof(*argv)); 172 if (argv == NULL) { 173 errno = ENOMEM; 174 return (-1); 175 } 176 #if __STDC__ 177 va_start(ap, arg); 178 #else 179 va_start(ap); 180 #endif 181 n = 1; 182 argv[0] = (char *)arg; 183 while ((argv[n] = va_arg(ap, char *)) != NULL) 184 n++; 185 va_end(ap); 186 return (execvp(name, argv)); 187 } 188 189 int 190 execv(name, argv) 191 const char *name; 192 char * const *argv; 193 { 194 (void)_execve(name, argv, environ); 195 return (-1); 196 } 197 198 int 199 execvp(name, argv) 200 const char *name; 201 char * const *argv; 202 { 203 char **memp; 204 register int cnt, lp, ln; 205 register char *p; 206 int eacces, save_errno; 207 char *bp, *cur, *path, buf[MAXPATHLEN]; 208 struct stat sb; 209 210 eacces = 0; 211 212 /* If it's an absolute or relative path name, it's easy. */ 213 if (index(name, '/')) { 214 bp = (char *)name; 215 cur = path = NULL; 216 goto retry; 217 } 218 bp = buf; 219 220 /* If it's an empty path name, fail in the usual POSIX way. */ 221 if (*name == '\0') { 222 errno = ENOENT; 223 return (-1); 224 } 225 226 /* Get the path we're searching. */ 227 if (!(path = getenv("PATH"))) 228 path = _PATH_DEFPATH; 229 cur = alloca(strlen(path) + 1); 230 if (cur == NULL) { 231 errno = ENOMEM; 232 return (-1); 233 } 234 strcpy(cur, path); 235 path = cur; 236 while ( (p = strsep(&cur, ":")) ) { 237 /* 238 * It's a SHELL path -- double, leading and trailing colons 239 * mean the current directory. 240 */ 241 if (!*p) { 242 p = "."; 243 lp = 1; 244 } else 245 lp = strlen(p); 246 ln = strlen(name); 247 248 /* 249 * If the path is too long complain. This is a possible 250 * security issue; given a way to make the path too long 251 * the user may execute the wrong program. 252 */ 253 if (lp + ln + 2 > sizeof(buf)) { 254 (void)_write(STDERR_FILENO, "execvp: ", 8); 255 (void)_write(STDERR_FILENO, p, lp); 256 (void)_write(STDERR_FILENO, ": path too long\n", 257 16); 258 continue; 259 } 260 bcopy(p, buf, lp); 261 buf[lp] = '/'; 262 bcopy(name, buf + lp + 1, ln); 263 buf[lp + ln + 1] = '\0'; 264 265 retry: (void)_execve(bp, argv, environ); 266 switch(errno) { 267 case E2BIG: 268 goto done; 269 case ELOOP: 270 case ENAMETOOLONG: 271 case ENOENT: 272 break; 273 case ENOEXEC: 274 for (cnt = 0; argv[cnt]; ++cnt) 275 ; 276 memp = alloca((cnt + 2) * sizeof(char *)); 277 if (memp == NULL) { 278 /* errno = ENOMEM; XXX override ENOEXEC? */ 279 goto done; 280 } 281 memp[0] = "sh"; 282 memp[1] = bp; 283 bcopy(argv + 1, memp + 2, cnt * sizeof(char *)); 284 (void)_execve(_PATH_BSHELL, memp, environ); 285 goto done; 286 case ENOMEM: 287 goto done; 288 case ENOTDIR: 289 break; 290 case ETXTBSY: 291 /* 292 * We used to retry here, but sh(1) doesn't. 293 */ 294 goto done; 295 default: 296 /* 297 * EACCES may be for an inaccessible directory or 298 * a non-executable file. Call stat() to decide 299 * which. This also handles ambiguities for EFAULT 300 * and EIO, and undocumented errors like ESTALE. 301 * We hope that the race for a stat() is unimportant. 302 */ 303 save_errno = errno; 304 if (stat(bp, &sb) != 0) 305 break; 306 if (save_errno == EACCES) { 307 eacces = 1; 308 continue; 309 } 310 errno = save_errno; 311 goto done; 312 } 313 } 314 if (eacces) 315 errno = EACCES; 316 else 317 errno = ENOENT; 318 done: 319 return (-1); 320 } 321