1/*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1983, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#if 0 33#ifndef lint 34static const char copyright[] = 35"@(#) Copyright (c) 1983, 1993\n\ 36 The Regents of the University of California. All rights reserved.\n"; 37#endif /* not lint */ 38 39#ifndef lint 40static char sccsid[] = "@(#)uudecode.c 8.2 (Berkeley) 4/2/94"; 41#endif /* not lint */ 42#endif 43#include <sys/cdefs.h> 44__FBSDID("$FreeBSD$"); 45 46/* 47 * uudecode [file ...] 48 * 49 * create the specified file, decoding as you go. 50 * used with uuencode. 51 */ 52#include <sys/param.h> 53#include <sys/socket.h> 54#include <sys/stat.h> 55 56#include <netinet/in.h> 57 58#include <ctype.h> 59#include <err.h> 60#include <errno.h> 61#include <fcntl.h> 62#include <libgen.h> 63#include <pwd.h> 64#include <resolv.h> 65#include <stdio.h> 66#include <stdlib.h> 67#include <string.h> 68#include <unistd.h> 69 70static const char *infile, *outfile; 71static FILE *infp, *outfp; 72static int base64, cflag, iflag, oflag, pflag, rflag, sflag; 73 74static void usage(void); 75static int decode(void); 76static int decode2(void); 77static int uu_decode(void); 78static int base64_decode(void); 79 80int 81main(int argc, char *argv[]) 82{ 83 int rval, ch; 84 85 if (strcmp(basename(argv[0]), "b64decode") == 0) 86 base64 = 1; 87 88 while ((ch = getopt(argc, argv, "cimo:prs")) != -1) { 89 switch (ch) { 90 case 'c': 91 if (oflag || rflag) 92 usage(); 93 cflag = 1; /* multiple uudecode'd files */ 94 break; 95 case 'i': 96 iflag = 1; /* ask before override files */ 97 break; 98 case 'm': 99 base64 = 1; 100 break; 101 case 'o': 102 if (cflag || pflag || rflag || sflag) 103 usage(); 104 oflag = 1; /* output to the specified file */ 105 sflag = 1; /* do not strip pathnames for output */ 106 outfile = optarg; /* set the output filename */ 107 break; 108 case 'p': 109 if (oflag) 110 usage(); 111 pflag = 1; /* print output to stdout */ 112 break; 113 case 'r': 114 if (cflag || oflag) 115 usage(); 116 rflag = 1; /* decode raw data */ 117 break; 118 case 's': 119 if (oflag) 120 usage(); 121 sflag = 1; /* do not strip pathnames for output */ 122 break; 123 default: 124 usage(); 125 } 126 } 127 argc -= optind; 128 argv += optind; 129 130 if (*argv != NULL) { 131 rval = 0; 132 do { 133 infp = fopen(infile = *argv, "r"); 134 if (infp == NULL) { 135 warn("%s", *argv); 136 rval = 1; 137 continue; 138 } 139 rval |= decode(); 140 fclose(infp); 141 } while (*++argv); 142 } else { 143 infile = "stdin"; 144 infp = stdin; 145 rval = decode(); 146 } 147 exit(rval); 148} 149 150static int 151decode(void) 152{ 153 int r, v; 154 155 if (rflag) { 156 /* relaxed alternative to decode2() */ 157 outfile = "/dev/stdout"; 158 outfp = stdout; 159 if (base64) 160 return (base64_decode()); 161 else 162 return (uu_decode()); 163 } 164 v = decode2(); 165 if (v == EOF) { 166 warnx("%s: missing or bad \"begin\" line", infile); 167 return (1); 168 } 169 for (r = v; cflag; r |= v) { 170 v = decode2(); 171 if (v == EOF) 172 break; 173 } 174 return (r); 175} 176 177static int 178decode2(void) 179{ 180 int flags, fd, mode; 181 size_t n, m; 182 char *p, *q; 183 void *handle; 184 struct passwd *pw; 185 struct stat st; 186 char buf[MAXPATHLEN + 1]; 187 188 base64 = 0; 189 /* search for header line */ 190 for (;;) { 191 if (fgets(buf, sizeof(buf), infp) == NULL) 192 return (EOF); 193 p = buf; 194 if (strncmp(p, "begin-base64 ", 13) == 0) { 195 base64 = 1; 196 p += 13; 197 } else if (strncmp(p, "begin ", 6) == 0) 198 p += 6; 199 else 200 continue; 201 /* p points to mode */ 202 q = strchr(p, ' '); 203 if (q == NULL) 204 continue; 205 *q++ = '\0'; 206 /* q points to filename */ 207 n = strlen(q); 208 while (n > 0 && (q[n-1] == '\n' || q[n-1] == '\r')) 209 q[--n] = '\0'; 210 /* found valid header? */ 211 if (n > 0) 212 break; 213 } 214 215 handle = setmode(p); 216 if (handle == NULL) { 217 warnx("%s: unable to parse file mode", infile); 218 return (1); 219 } 220 mode = getmode(handle, 0) & 0666; 221 free(handle); 222 223 if (sflag) { 224 /* don't strip, so try ~user/file expansion */ 225 p = NULL; 226 pw = NULL; 227 if (*q == '~') 228 p = strchr(q, '/'); 229 if (p != NULL) { 230 *p = '\0'; 231 pw = getpwnam(q + 1); 232 *p = '/'; 233 } 234 if (pw != NULL) { 235 n = strlen(pw->pw_dir); 236 if (buf + n > p) { 237 /* make room */ 238 m = strlen(p); 239 if (sizeof(buf) < n + m) { 240 warnx("%s: bad output filename", 241 infile); 242 return (1); 243 } 244 p = memmove(buf + n, p, m); 245 } 246 q = memcpy(p - n, pw->pw_dir, n); 247 } 248 } else { 249 /* strip down to leaf name */ 250 p = strrchr(q, '/'); 251 if (p != NULL) 252 q = p + 1; 253 } 254 if (!oflag) 255 outfile = q; 256 257 /* POSIX says "/dev/stdout" is a 'magic cookie' not a special file. */ 258 if (pflag || strcmp(outfile, "/dev/stdout") == 0) 259 outfp = stdout; 260 else { 261 flags = O_WRONLY | O_CREAT | O_EXCL; 262 if (lstat(outfile, &st) == 0) { 263 if (iflag) { 264 warnc(EEXIST, "%s: %s", infile, outfile); 265 return (0); 266 } 267 switch (st.st_mode & S_IFMT) { 268 case S_IFREG: 269 case S_IFLNK: 270 /* avoid symlink attacks */ 271 if (unlink(outfile) == 0 || errno == ENOENT) 272 break; 273 warn("%s: unlink %s", infile, outfile); 274 return (1); 275 case S_IFDIR: 276 warnc(EISDIR, "%s: %s", infile, outfile); 277 return (1); 278 default: 279 if (oflag) { 280 /* trust command-line names */ 281 flags &= ~O_EXCL; 282 break; 283 } 284 warnc(EEXIST, "%s: %s", infile, outfile); 285 return (1); 286 } 287 } else if (errno != ENOENT) { 288 warn("%s: %s", infile, outfile); 289 return (1); 290 } 291 if ((fd = open(outfile, flags, mode)) < 0 || 292 (outfp = fdopen(fd, "w")) == NULL) { 293 warn("%s: %s", infile, outfile); 294 return (1); 295 } 296 } 297 298 if (base64) 299 return (base64_decode()); 300 else 301 return (uu_decode()); 302} 303 304static int 305get_line(char *buf, size_t size) 306{ 307 308 if (fgets(buf, size, infp) != NULL) 309 return (2); 310 if (rflag) 311 return (0); 312 warnx("%s: %s: short file", infile, outfile); 313 return (1); 314} 315 316static int 317checkend(const char *ptr, const char *end, const char *msg) 318{ 319 size_t n; 320 321 n = strlen(end); 322 if (strncmp(ptr, end, n) != 0 || 323 strspn(ptr + n, " \t\r\n") != strlen(ptr + n)) { 324 warnx("%s: %s: %s", infile, outfile, msg); 325 return (1); 326 } 327 if (fclose(outfp) != 0) { 328 warn("%s: %s", infile, outfile); 329 return (1); 330 } 331 return (0); 332} 333 334static int 335uu_decode(void) 336{ 337 int i, ch; 338 char *p; 339 char buf[MAXPATHLEN+1]; 340 341 /* for each input line */ 342 for (;;) { 343 switch (get_line(buf, sizeof(buf))) { 344 case 0: 345 return (0); 346 case 1: 347 return (1); 348 } 349 350#define DEC(c) (((c) - ' ') & 077) /* single character decode */ 351#define IS_DEC(c) ( (((c) - ' ') >= 0) && (((c) - ' ') <= 077 + 1) ) 352 353#define OUT_OF_RANGE do { \ 354 warnx("%s: %s: character out of range: [%d-%d]", \ 355 infile, outfile, 1 + ' ', 077 + ' ' + 1); \ 356 return (1); \ 357} while (0) 358 359 /* 360 * `i' is used to avoid writing out all the characters 361 * at the end of the file. 362 */ 363 p = buf; 364 if ((i = DEC(*p)) <= 0) 365 break; 366 for (++p; i > 0; p += 4, i -= 3) 367 if (i >= 3) { 368 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) && 369 IS_DEC(*(p + 2)) && IS_DEC(*(p + 3)))) 370 OUT_OF_RANGE; 371 372 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 373 putc(ch, outfp); 374 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 375 putc(ch, outfp); 376 ch = DEC(p[2]) << 6 | DEC(p[3]); 377 putc(ch, outfp); 378 } else { 379 if (i >= 1) { 380 if (!(IS_DEC(*p) && IS_DEC(*(p + 1)))) 381 OUT_OF_RANGE; 382 ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4; 383 putc(ch, outfp); 384 } 385 if (i >= 2) { 386 if (!(IS_DEC(*(p + 1)) && 387 IS_DEC(*(p + 2)))) 388 OUT_OF_RANGE; 389 390 ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2; 391 putc(ch, outfp); 392 } 393 if (i >= 3) { 394 if (!(IS_DEC(*(p + 2)) && 395 IS_DEC(*(p + 3)))) 396 OUT_OF_RANGE; 397 ch = DEC(p[2]) << 6 | DEC(p[3]); 398 putc(ch, outfp); 399 } 400 } 401 } 402 switch (get_line(buf, sizeof(buf))) { 403 case 0: 404 return (0); 405 case 1: 406 return (1); 407 default: 408 return (checkend(buf, "end", "no \"end\" line")); 409 } 410} 411 412static int 413base64_decode(void) 414{ 415 int n, count, count4; 416 char inbuf[MAXPATHLEN + 1], *p; 417 unsigned char outbuf[MAXPATHLEN * 4]; 418 char leftover[MAXPATHLEN + 1]; 419 420 leftover[0] = '\0'; 421 for (;;) { 422 strcpy(inbuf, leftover); 423 switch (get_line(inbuf + strlen(inbuf), 424 sizeof(inbuf) - strlen(inbuf))) { 425 case 0: 426 return (0); 427 case 1: 428 return (1); 429 } 430 431 count = 0; 432 count4 = -1; 433 p = inbuf; 434 while (*p != '\0') { 435 /* 436 * Base64 encoded strings have the following 437 * characters in them: A-Z, a-z, 0-9 and +, / and = 438 */ 439 if (isalnum(*p) || *p == '+' || *p == '/' || *p == '=') 440 count++; 441 if (count % 4 == 0) 442 count4 = p - inbuf; 443 p++; 444 } 445 446 strcpy(leftover, inbuf + count4 + 1); 447 inbuf[count4 + 1] = 0; 448 449 n = b64_pton(inbuf, outbuf, sizeof(outbuf)); 450 451 if (n < 0) 452 break; 453 fwrite(outbuf, 1, n, outfp); 454 } 455 return (checkend(inbuf, "====", "error decoding base64 input stream")); 456} 457 458static void 459usage(void) 460{ 461 462 (void)fprintf(stderr, 463 "usage: uudecode [-cimprs] [file ...]\n" 464 " uudecode [-i] -o output_file [file]\n" 465 " b64decode [-cimprs] [file ...]\n" 466 " b64decode [-i] -o output_file [file]\n"); 467 exit(1); 468} 469