1 /*- 2 * Copyright (c) 1983, 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 * @(#) Copyright (c) 1983, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)uudecode.c 8.2 (Berkeley) 4/2/94 35 * $FreeBSD: src/usr.bin/uudecode/uudecode.c,v 1.13.2.6 2003/04/07 20:10:33 fanf Exp $ 36 * $DragonFly: src/usr.bin/uudecode/uudecode.c,v 1.3 2004/12/22 11:25:51 liamfoy Exp $ 37 */ 38 39 /* 40 * uudecode [file ...] 41 * 42 * create the specified file, decoding as you go. 43 * used with uuencode. 44 */ 45 #include <sys/param.h> 46 #include <sys/socket.h> 47 #include <sys/stat.h> 48 49 #include <netinet/in.h> 50 51 #include <err.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <libgen.h> 55 #include <pwd.h> 56 #include <resolv.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <unistd.h> 61 62 static const char *infile, *outfile; 63 static FILE *infp, *outfp; 64 static int base64, cflag, iflag, oflag, pflag, rflag, sflag; 65 66 static void usage(void); 67 static int decode(void); 68 static int decode2(void); 69 static int uu_decode(void); 70 static int base64_decode(void); 71 72 int 73 main(int argc, char *argv[]) 74 { 75 int rval, ch; 76 77 if (strcmp(basename(argv[0]), "b64decode") == 0) 78 base64 = 1; 79 80 while ((ch = getopt(argc, argv, "cimo:prs")) != -1) { 81 switch(ch) { 82 case 'c': 83 if (oflag || rflag) 84 usage(); 85 cflag = 1; /* multiple uudecode'd files */ 86 break; 87 case 'i': 88 iflag = 1; /* ask before override files */ 89 break; 90 case 'm': 91 base64 = 1; 92 break; 93 case 'o': 94 if (cflag || pflag || rflag || sflag) 95 usage(); 96 oflag = 1; /* output to the specified file */ 97 sflag = 1; /* do not strip pathnames for output */ 98 outfile = optarg; /* set the output filename */ 99 break; 100 case 'p': 101 if (oflag) 102 usage(); 103 pflag = 1; /* print output to stdout */ 104 break; 105 case 'r': 106 if (cflag || oflag) 107 usage(); 108 rflag = 1; /* decode raw data */ 109 break; 110 case 's': 111 if (oflag) 112 usage(); 113 sflag = 1; /* do not strip pathnames for output */ 114 break; 115 default: 116 usage(); 117 } 118 } 119 argc -= optind; 120 argv += optind; 121 122 if (*argv) { 123 rval = 0; 124 do { 125 infp = fopen(infile = *argv, "r"); 126 if (infp == NULL) { 127 warn("%s", *argv); 128 rval = 1; 129 continue; 130 } 131 rval |= decode(); 132 fclose(infp); 133 } while (*++argv); 134 } else { 135 infile = "stdin"; 136 infp = stdin; 137 rval = decode(); 138 } 139 exit(rval); 140 } 141 142 static int 143 decode(void) 144 { 145 int r, v; 146 147 if (rflag) { 148 /* relaxed alternative to decode2() */ 149 outfile = "/dev/stdout"; 150 outfp = stdout; 151 if (base64) 152 return (base64_decode()); 153 else 154 return (uu_decode()); 155 } 156 v = decode2(); 157 if (v == EOF) { 158 warnx("%s: missing or bad \"begin\" line", infile); 159 return (1); 160 } 161 for (r = v; cflag; r |= v) { 162 v = decode2(); 163 if (v == EOF) 164 break; 165 } 166 return (r); 167 } 168 169 static int 170 decode2(void) 171 { 172 int flags, fd; 173 size_t n, m; 174 char *p, *q; 175 void *handle; 176 mode_t mode; 177 struct passwd *pw; 178 struct stat st; 179 char buf[MAXPATHLEN+1]; 180 181 base64 = 0; 182 /* search for header line */ 183 for (;;) { 184 if (fgets(buf, sizeof(buf), infp) == NULL) 185 return (EOF); 186 p = buf; 187 if (strncmp(p, "begin-base64 ", 13) == 0) { 188 base64 = 1; 189 p += 13; 190 } else if (strncmp(p, "begin ", 6) == 0) 191 p += 6; 192 else 193 continue; 194 /* p points to mode */ 195 q = strchr(p, ' '); 196 if (q == NULL) 197 continue; 198 *q++ = '\0'; 199 /* q points to filename */ 200 n = strlen(q); 201 while (n > 0 && (q[n-1] == '\n' || q[n-1] == '\r')) 202 q[--n] = '\0'; 203 /* found valid header? */ 204 if (n > 0) 205 break; 206 } 207 208 errno = 0; 209 if ((handle = setmode(p)) == NULL) { 210 if (!errno) 211 warnx("invalid file mode: %s", infile); 212 else 213 warn("setmode malloc failed: %s", infile); 214 215 return(1); 216 } 217 218 mode = getmode(handle, 0) & 0666; 219 free(handle); 220 221 if (sflag) { 222 /* don't strip, so try ~user/file expansion */ 223 p = NULL; 224 pw = NULL; 225 if (*q == '~') 226 p = strchr(q, '/'); 227 if (p != NULL) { 228 *p = '\0'; 229 pw = getpwnam(q + 1); 230 *p = '/'; 231 } 232 if (pw != NULL) { 233 n = strlen(pw->pw_dir); 234 if (buf + n > p) { 235 /* make room */ 236 m = strlen(p); 237 if (sizeof(buf) < n + m) { 238 warnx("%s: bad output filename", 239 infile); 240 return (1); 241 } 242 p = memmove(buf + n, p, m); 243 } 244 q = memcpy(p - n, pw->pw_dir, n); 245 } 246 } else { 247 /* strip down to leaf name */ 248 p = strrchr(q, '/'); 249 if (p != NULL) 250 q = p + 1; 251 } 252 if (!oflag) 253 outfile = q; 254 255 /* POSIX says "/dev/stdout" is a 'magic cookie' not a special file. */ 256 if (pflag || strcmp(outfile, "/dev/stdout") == 0) 257 outfp = stdout; 258 else { 259 flags = O_WRONLY|O_CREAT|O_EXCL; 260 if (lstat(outfile, &st) == 0) { 261 if (iflag) { 262 warnc(EEXIST, "%s: %s", infile, outfile); 263 return (0); 264 } 265 switch (st.st_mode & S_IFMT) { 266 case S_IFREG: 267 case S_IFLNK: 268 /* avoid symlink attacks */ 269 if (unlink(outfile) == 0 || errno == ENOENT) 270 break; 271 warn("%s: unlink %s", infile, outfile); 272 return (1); 273 case S_IFDIR: 274 warnc(EISDIR, "%s: %s", infile, outfile); 275 return (1); 276 default: 277 if (oflag) { 278 /* trust command-line names */ 279 flags &= ~O_EXCL; 280 break; 281 } 282 warnc(EEXIST, "%s: %s", infile, outfile); 283 return (1); 284 } 285 } else if (errno != ENOENT) { 286 warn("%s: %s", infile, outfile); 287 return (1); 288 } 289 if ((fd = open(outfile, flags, mode)) < 0 || 290 (outfp = fdopen(fd, "w")) == NULL) { 291 warn("%s: %s", infile, outfile); 292 return (1); 293 } 294 } 295 296 if (base64) 297 return (base64_decode()); 298 else 299 return (uu_decode()); 300 } 301 302 static int 303 getline(char *buf, size_t size) 304 { 305 if (fgets(buf, size, infp) != NULL) 306 return (2); 307 if (rflag) 308 return (0); 309 warnx("%s: %s: short file", infile, outfile); 310 return (1); 311 } 312 313 static int 314 checkend(const char *ptr, const char *end, const char *msg) 315 { 316 size_t n; 317 318 n = strlen(end); 319 if (strncmp(ptr, end, n) != 0 || 320 strspn(ptr + n, " \t\r\n") != strlen(ptr + n)) { 321 warnx("%s: %s: %s", infile, outfile, msg); 322 return (1); 323 } 324 if (fclose(outfp) != 0) { 325 warn("%s: %s", infile, outfile); 326 return (1); 327 } 328 return (0); 329 } 330 331 static int 332 uu_decode(void) 333 { 334 int i, ch; 335 char *p; 336 char buf[MAXPATHLEN+1]; 337 338 /* for each input line */ 339 for (;;) { 340 switch (getline(buf, sizeof(buf))) { 341 case 0: return (0); 342 case 1: return (1); 343 } 344 345 #define DEC(c) (((c) - ' ') & 077) /* single character decode */ 346 #define IS_DEC(c) ( (((c) - ' ') >= 0) && (((c) - ' ') <= 077 + 1) ) 347 348 #define OUT_OF_RANGE do { \ 349 warnx("%s: %s: character out of range: [%d-%d]", \ 350 infile, outfile, 1 + ' ', 077 + ' ' + 1); \ 351 return (1); \ 352 } while (0) 353 354 /* 355 * `i' is used to avoid writing out all the characters 356 * at the end of the file. 357 */ 358 p = buf; 359 if ((i = DEC(*p)) <= 0) 360 break; 361 for (++p; i > 0; p += 4, i -= 3) 362 if (i >= 3) { 363 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) && 364 IS_DEC(*(p + 2)) && IS_DEC(*(p + 3)))) 365 OUT_OF_RANGE; 366 367 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 368 putc(ch, outfp); 369 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 370 putc(ch, outfp); 371 ch = DEC(p[2]) << 6 | DEC(p[3]); 372 putc(ch, outfp); 373 } 374 else { 375 if (i >= 1) { 376 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)))) 377 OUT_OF_RANGE; 378 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 379 putc(ch, outfp); 380 } 381 if (i >= 2) { 382 if (!(IS_DEC(*(p + 1)) && 383 IS_DEC(*(p + 2)))) 384 OUT_OF_RANGE; 385 386 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 387 putc(ch, outfp); 388 } 389 if (i >= 3) { 390 if (!(IS_DEC(*(p + 2)) && 391 IS_DEC(*(p + 3)))) 392 OUT_OF_RANGE; 393 ch = DEC(p[2]) << 6 | DEC(p[3]); 394 putc(ch, outfp); 395 } 396 } 397 } 398 switch (getline(buf, sizeof(buf))) { 399 case 0: return (0); 400 case 1: return (1); 401 default: return (checkend(buf, "end", "no \"end\" line")); 402 } 403 } 404 405 static int 406 base64_decode(void) 407 { 408 int n; 409 char inbuf[MAXPATHLEN+1]; 410 unsigned char outbuf[MAXPATHLEN * 4]; 411 412 for (;;) { 413 switch (getline(inbuf, sizeof(inbuf))) { 414 case 0: return (0); 415 case 1: return (1); 416 } 417 n = b64_pton(inbuf, outbuf, sizeof(outbuf)); 418 if (n < 0) 419 break; 420 fwrite(outbuf, 1, n, outfp); 421 } 422 return (checkend(inbuf, "====", 423 "error decoding base64 input stream")); 424 } 425 426 static void 427 usage(void) 428 { 429 (void)fprintf(stderr, 430 "usage: uudecode [-cimprs] [file ...]\n" 431 " uudecode [-i] -o output_file [file]\n" 432 " b64decode [-cimprs] [file ...]\n" 433 " b64decode [-i] -o output_file [file]\n"); 434 exit(1); 435 } 436