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 1.2 2003/06/17 04:29:33 dillon 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, mode; 173 size_t n, m; 174 char *p, *q; 175 void *handle; 176 struct passwd *pw; 177 struct stat st; 178 char buf[MAXPATHLEN+1]; 179 180 base64 = 0; 181 /* search for header line */ 182 for (;;) { 183 if (fgets(buf, sizeof(buf), infp) == NULL) 184 return (EOF); 185 p = buf; 186 if (strncmp(p, "begin-base64 ", 13) == 0) { 187 base64 = 1; 188 p += 13; 189 } else if (strncmp(p, "begin ", 6) == 0) 190 p += 6; 191 else 192 continue; 193 /* p points to mode */ 194 q = strchr(p, ' '); 195 if (q == NULL) 196 continue; 197 *q++ = '\0'; 198 /* q points to filename */ 199 n = strlen(q); 200 while (n > 0 && (q[n-1] == '\n' || q[n-1] == '\r')) 201 q[--n] = '\0'; 202 /* found valid header? */ 203 if (n > 0) 204 break; 205 } 206 207 handle = setmode(p); 208 if (handle == NULL) { 209 warnx("%s: unable to parse file mode", infile); 210 return (1); 211 } 212 mode = getmode(handle, 0) & 0666; 213 free(handle); 214 215 if (sflag) { 216 /* don't strip, so try ~user/file expansion */ 217 p = NULL; 218 pw = NULL; 219 if (*q == '~') 220 p = strchr(q, '/'); 221 if (p != NULL) { 222 *p = '\0'; 223 pw = getpwnam(q + 1); 224 *p = '/'; 225 } 226 if (pw != NULL) { 227 n = strlen(pw->pw_dir); 228 if (buf + n > p) { 229 /* make room */ 230 m = strlen(p); 231 if (sizeof(buf) < n + m) { 232 warnx("%s: bad output filename", 233 infile); 234 return (1); 235 } 236 p = memmove(buf + n, p, m); 237 } 238 q = memcpy(p - n, pw->pw_dir, n); 239 } 240 } else { 241 /* strip down to leaf name */ 242 p = strrchr(q, '/'); 243 if (p != NULL) 244 q = p + 1; 245 } 246 if (!oflag) 247 outfile = q; 248 249 /* POSIX says "/dev/stdout" is a 'magic cookie' not a special file. */ 250 if (pflag || strcmp(outfile, "/dev/stdout") == 0) 251 outfp = stdout; 252 else { 253 flags = O_WRONLY|O_CREAT|O_EXCL; 254 if (lstat(outfile, &st) == 0) { 255 if (iflag) { 256 warnc(EEXIST, "%s: %s", infile, outfile); 257 return (0); 258 } 259 switch (st.st_mode & S_IFMT) { 260 case S_IFREG: 261 case S_IFLNK: 262 /* avoid symlink attacks */ 263 if (unlink(outfile) == 0 || errno == ENOENT) 264 break; 265 warn("%s: unlink %s", infile, outfile); 266 return (1); 267 case S_IFDIR: 268 warnc(EISDIR, "%s: %s", infile, outfile); 269 return (1); 270 default: 271 if (oflag) { 272 /* trust command-line names */ 273 flags &= ~O_EXCL; 274 break; 275 } 276 warnc(EEXIST, "%s: %s", infile, outfile); 277 return (1); 278 } 279 } else if (errno != ENOENT) { 280 warn("%s: %s", infile, outfile); 281 return (1); 282 } 283 if ((fd = open(outfile, flags, mode)) < 0 || 284 (outfp = fdopen(fd, "w")) == NULL) { 285 warn("%s: %s", infile, outfile); 286 return (1); 287 } 288 } 289 290 if (base64) 291 return (base64_decode()); 292 else 293 return (uu_decode()); 294 } 295 296 static int 297 getline(char *buf, size_t size) 298 { 299 if (fgets(buf, size, infp) != NULL) 300 return (2); 301 if (rflag) 302 return (0); 303 warnx("%s: %s: short file", infile, outfile); 304 return (1); 305 } 306 307 static int 308 checkend(const char *ptr, const char *end, const char *msg) 309 { 310 size_t n; 311 312 n = strlen(end); 313 if (strncmp(ptr, end, n) != 0 || 314 strspn(ptr + n, " \t\r\n") != strlen(ptr + n)) { 315 warnx("%s: %s: %s", infile, outfile, msg); 316 return (1); 317 } 318 if (fclose(outfp) != 0) { 319 warn("%s: %s", infile, outfile); 320 return (1); 321 } 322 return (0); 323 } 324 325 static int 326 uu_decode(void) 327 { 328 int i, ch; 329 char *p; 330 char buf[MAXPATHLEN+1]; 331 332 /* for each input line */ 333 for (;;) { 334 switch (getline(buf, sizeof(buf))) { 335 case 0: return (0); 336 case 1: return (1); 337 } 338 339 #define DEC(c) (((c) - ' ') & 077) /* single character decode */ 340 #define IS_DEC(c) ( (((c) - ' ') >= 0) && (((c) - ' ') <= 077 + 1) ) 341 342 #define OUT_OF_RANGE do { \ 343 warnx("%s: %s: character out of range: [%d-%d]", \ 344 infile, outfile, 1 + ' ', 077 + ' ' + 1); \ 345 return (1); \ 346 } while (0) 347 348 /* 349 * `i' is used to avoid writing out all the characters 350 * at the end of the file. 351 */ 352 p = buf; 353 if ((i = DEC(*p)) <= 0) 354 break; 355 for (++p; i > 0; p += 4, i -= 3) 356 if (i >= 3) { 357 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) && 358 IS_DEC(*(p + 2)) && IS_DEC(*(p + 3)))) 359 OUT_OF_RANGE; 360 361 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 362 putc(ch, outfp); 363 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 364 putc(ch, outfp); 365 ch = DEC(p[2]) << 6 | DEC(p[3]); 366 putc(ch, outfp); 367 } 368 else { 369 if (i >= 1) { 370 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)))) 371 OUT_OF_RANGE; 372 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 373 putc(ch, outfp); 374 } 375 if (i >= 2) { 376 if (!(IS_DEC(*(p + 1)) && 377 IS_DEC(*(p + 2)))) 378 OUT_OF_RANGE; 379 380 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 381 putc(ch, outfp); 382 } 383 if (i >= 3) { 384 if (!(IS_DEC(*(p + 2)) && 385 IS_DEC(*(p + 3)))) 386 OUT_OF_RANGE; 387 ch = DEC(p[2]) << 6 | DEC(p[3]); 388 putc(ch, outfp); 389 } 390 } 391 } 392 switch (getline(buf, sizeof(buf))) { 393 case 0: return (0); 394 case 1: return (1); 395 default: return (checkend(buf, "end", "no \"end\" line")); 396 } 397 } 398 399 static int 400 base64_decode(void) 401 { 402 int n; 403 char inbuf[MAXPATHLEN+1]; 404 unsigned char outbuf[MAXPATHLEN * 4]; 405 406 for (;;) { 407 switch (getline(inbuf, sizeof(inbuf))) { 408 case 0: return (0); 409 case 1: return (1); 410 } 411 n = b64_pton(inbuf, outbuf, sizeof(outbuf)); 412 if (n < 0) 413 break; 414 fwrite(outbuf, 1, n, outfp); 415 } 416 return (checkend(inbuf, "====", 417 "error decoding base64 input stream")); 418 } 419 420 static void 421 usage(void) 422 { 423 (void)fprintf(stderr, 424 "usage: uudecode [-cimprs] [file ...]\n" 425 " uudecode [-i] -o output_file [file]\n" 426 " b64decode [-cimprs] [file ...]\n" 427 " b64decode [-i] -o output_file [file]\n"); 428 exit(1); 429 } 430