xref: /titanic_41/usr/src/cmd/bnu/uudecode.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 /*	Copyright 2004 Sun Microsystems, Inc.  All rights reserved. */
26 /*	Use is subject to license terms. */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 /*
31  * uudecode [-o outfile | -p] [input]
32  *
33  * create the specified file, decoding as you go.
34  * used with uuencode.
35  */
36 #include <unistd.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <pwd.h>
40 #include <string.h>
41 #include <strings.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <locale.h>
45 #include <nl_types.h>
46 #include <langinfo.h>
47 #include <iconv.h>
48 #include <limits.h>
49 #include <errno.h>
50 #include <ctype.h>
51 #include <signal.h>
52 #include <stdarg.h>
53 
54 #define	BUFSIZE	90	/* must be a multiple of 3 */
55 
56 #define	TABLE_SIZE	0x40
57 
58 #define	isvalid(octet)	(octet <= 0x40)
59 
60 /*
61  * base64 decoding table
62  */
63 /* BEGIN CSTYLED */
64 static char base64tab[] = {
65 	'\377', '\377', '\377', '\377', '\377', '\377', '\377', '\377',
66 	'\377', '\377', '\377', '\377', '\377', '\377', '\377', '\377',
67 	'\377', '\377', '\377', '\377', '\377', '\377', '\377', '\377',
68 	'\377', '\377', '\377', '\377', '\377', '\377', '\377', '\377',
69 	'\377', '\377', '\377', '\377', '\377', '\377', '\377', '\377',
70 	'\377', '\377', '\377',     62, '\377', '\377', '\377',     63,
71 	    52,     53,     54,     55,     56,     57,     58,     59,
72 	    60,     61, '\377', '\377', '\377', '\377', '\377', '\377',
73 	'\377',      0,      1,      2,      3,      4,      5,      6,
74 	     7,      8,      9,     10,     11,     12,     13,     14,
75 	    15,     16,     17,     18,     19,     20,     21,     22,
76 	    23,     24,     25, '\377', '\377', '\377', '\377', '\377',
77 	'\377',     26,     27,     28,     29,     30,     31,     32,
78 	    33,     34,     35,     36,     37,     38,     39,     40,
79 	    41,     42,     43,     44,     45,     46,     47,     48,
80 	    49,     50,     51, '\377', '\377', '\377', '\377', '\377'
81 };
82 /* END CSTYLED */
83 
84 static char	decode_table[UCHAR_MAX + 1];
85 
86 /* DEC is the basic 1 character decoding function (historical algorithm) */
87 #define	DEC(c)	decode_table[c]
88 
89 /* true if the character is in the base64 encoding table */
90 #define	validbase64(c) (('A' <= (c) && (c) <= 'Z') || \
91 		('a' <= (c) && (c) <= 'z') || \
92 		('0' <= (c) && (c) <= '9') || \
93 		(c) == '+' || (c) == '/')
94 
95 static void	decode(FILE *, FILE *, int);
96 static int	outdec(unsigned char *, unsigned char *, int);
97 static int	outdec64(unsigned char *, unsigned char *, int);
98 
99 /* from usr/src/cmd/chmod/common.c */
100 
101 void errmsg(int severity, int code, char *format, ...);
102 
103 extern mode_t newmode(char *ms, mode_t new_mode, mode_t umsk,
104     char *file, char *path);
105 
106 static char	*prog;
107 static char	outfile[PATH_MAX];
108 static int	mode_err = 0;	/* mode conversion error flag */
109 
110 int
main(int argc,char ** argv)111 main(int argc, char **argv)
112 {
113 	FILE *in, *out;
114 	int pipeout = 0;
115 	int oflag = 0;
116 	int i;
117 	mode_t mode, p_umask;
118 	char dest[PATH_MAX];
119 	char modebits[1024];
120 	char buf[LINE_MAX];
121 	int	c, errflag = 0;
122 	struct stat sbuf;
123 	int base64flag = 0;
124 
125 	prog = argv[0];
126 	(void) signal(SIGPIPE, SIG_DFL);
127 	bzero(dest, sizeof (dest));
128 	outfile[0] = '\0';
129 
130 	/* Set locale environment variables local definitions */
131 	(void) setlocale(LC_ALL, "");
132 #if !defined(TEXT_DOMAIN)	/* Should be defined by cc -D */
133 #define	TEXT_DOMAIN "SYS_TEST"	/* Use this only if it wasn't */
134 #endif
135 	(void) textdomain(TEXT_DOMAIN);
136 	p_umask = umask((mode_t)0);
137 
138 	while ((c = getopt(argc, argv, "o:p")) != EOF) {
139 		switch (c) {
140 		case 'o':
141 			oflag++;
142 			(void) strncpy(outfile, optarg, sizeof (outfile));
143 			break;
144 		case 'p':
145 			pipeout++;
146 			break;
147 		default:
148 		case '?':
149 			errflag++;
150 			break;
151 		}
152 	}
153 	argc -= optind;
154 	argv = &argv[optind];
155 
156 	/* optional input arg */
157 	if (argc > 0) {
158 		if ((in = fopen(*argv, "r")) == NULL) {
159 			perror(*argv);
160 			exit(1);
161 		}
162 		argv++; argc--;
163 	} else {
164 		in = stdin;
165 		errno = 0;
166 		if (fstat(fileno(in), &sbuf) < 0) {
167 			perror("stdin");
168 			exit(1);
169 		}
170 	}
171 
172 	if ((argc > 0) || errflag || (oflag && pipeout)) {
173 		(void) fprintf(stderr,
174 		    gettext("Usage: %s [-o outfile | -p] [infile]\n"), prog);
175 		exit(2);
176 	}
177 
178 	/* search for header line */
179 	for (;;) {
180 		if (fgets(buf, sizeof (buf), in) == NULL) {
181 			/* suppress message if we printed a mode error */
182 			if (mode_err == 0)
183 				(void) fprintf(stderr,
184 				    gettext("No begin line\n"));
185 			exit(3);
186 		}
187 		/*
188 		 * the check for begin-base64 obviously needs to come
189 		 * first, since both algorithms' begin strings start
190 		 * with 'begin'.  Also verify that there is a valid
191 		 * octal or symbolic file mode.
192 		 */
193 		if (strncmp(buf, "begin-base64", 12) == 0) {
194 			base64flag = 1;
195 			mode_err = 0;
196 			if ((sscanf(buf + 13, "%1023s %1023s",
197 			    modebits, dest) == 2) &&
198 			    ((sscanf(modebits, "%lo", &mode) == 1) ||
199 				((mode = newmode(modebits, 0, p_umask,
200 				    "", "")) != 0) && mode_err == 0))
201 				break;
202 		} else if (strncmp(buf, "begin", 5) == 0) {
203 			base64flag = 0;
204 			mode_err = 0;
205 			if ((sscanf(buf + 6, "%1023s %1023s",
206 			    modebits, dest) == 2) &&
207 			    ((sscanf(modebits, "%lo", &mode) == 1) ||
208 				((mode = newmode(modebits, 0, p_umask,
209 				    "", "")) != 0) && mode_err == 0))
210 				break;
211 		}
212 	}
213 
214 	/*
215 	 * Now that we know the type of encoding used, we can
216 	 * initialize the decode table.
217 	 */
218 	if (base64flag == 0) {
219 		(void) memset(decode_table, 0xFF, sizeof (decode_table));
220 		for (i = 0; i <= TABLE_SIZE; i++)
221 			decode_table[(unsigned char)i + 0x20] =
222 			    (unsigned char)i & 0x3F;
223 	} else
224 		(void) memcpy(decode_table, base64tab, sizeof (base64tab));
225 
226 	/*
227 	 * Filename specified on the command line with -o
228 	 * overrides filename in the encoded file.
229 	 */
230 	if (outfile[0] != '\0')
231 		(void) strncpy(dest, outfile, sizeof (dest));
232 
233 	if (pipeout ||
234 	    (dest[0] == '-' && dest[1] == '\0' && outfile[0] == '\0')) {
235 		out = stdout;
236 		bzero(outfile, sizeof (outfile));
237 		bzero(dest, sizeof (dest));
238 	} else {
239 		/* handle ~user/file format */
240 		if (dest[0] == '~') {
241 			char *sl;
242 			struct passwd *user;
243 			char dnbuf[100];
244 
245 			sl = strchr(dest, '/');
246 			if (sl == NULL) {
247 				(void) fprintf(stderr,
248 				    gettext("Illegal ~user\n"));
249 				exit(3);
250 			}
251 			*sl++ = 0;
252 			user = getpwnam(dest+1);
253 			if (user == NULL) {
254 				(void) fprintf(stderr,
255 				    gettext("No such user as %s\n"), dest);
256 				exit(4);
257 			}
258 			(void) strncpy(dnbuf, user->pw_dir, sizeof (dnbuf));
259 			(void) strlcat(dnbuf, "/", sizeof (dnbuf));
260 			(void) strlcat(dnbuf, sl, sizeof (dnbuf));
261 			(void) strncpy(dest, dnbuf, sizeof (dest));
262 		}
263 	}
264 	/* if not using stdout, create file */
265 	if (dest[0] != '\0') {
266 		if ((out = fopen(dest, "w")) == NULL) {
267 			perror(dest);
268 			exit(4);
269 		}
270 		(void) chmod(dest, mode & 0777);
271 	}
272 
273 	decode(in, out, base64flag);
274 
275 	if (fclose(out) == EOF) {
276 		perror(prog);
277 		exit(6);
278 	}
279 
280 	return (0);
281 }
282 
283 /*
284  * copy from in to out, decoding as you go along.
285  */
286 
287 static void
decode(FILE * in,FILE * out,int base64)288 decode(FILE *in, FILE *out, int base64)
289 {
290 	char	inbuf[120], *ibp, *iptr;
291 	unsigned char 	outbuf[BUFSIZE], *obp, *optr;
292 	int	n, octets, warned, endseen, numbase64chars;
293 	unsigned char chr[4], curchr, ch;
294 	longlong_t line;
295 
296 	if (! base64) {	/* use historical algorithm */
297 		warned = 0;
298 		for (line = 1; ; line++) {
299 			/* for each input line */
300 			if (fgets(inbuf, sizeof (inbuf), in) == NULL) {
301 				(void) fprintf(stderr,
302 				    gettext("No end line\n"));
303 				exit(5);
304 			}
305 
306 			/* Is line == 'end\n'? */
307 			if (strcmp(inbuf, "end\n") == 0) {
308 				break;
309 			}
310 
311 			n = DEC(inbuf[0]);
312 
313 			if (n < 0)
314 				continue;
315 
316 			/*
317 			 * Decode data lines.
318 			 *
319 			 * Note that uuencode/uudecode uses only the portable
320 			 * character set for encoded data and the portable
321 			 * character set characters must be represented in
322 			 * a single byte.  We use this knowledge to reuse
323 			 * buffer space while decoding.
324 			 */
325 			octets = n;
326 			obp = (unsigned char *) &inbuf[0];
327 			ibp = &inbuf[1];
328 			while (octets > 0) {
329 				if ((ch = outdec((unsigned char *)obp,
330 				    (unsigned char *)ibp, octets))
331 				    != 0x20) {
332 					/* invalid characters where detected */
333 					if (!warned) {
334 						warned = 1;
335 						(void) fprintf(stderr,
336 						    gettext("Invalid character"
337 							" (0x%x) on line"
338 							" %lld\n"), ch, line);
339 					}
340 					break;
341 				}
342 				ibp += 4;
343 				obp += 3;
344 				octets -= 3;
345 			}
346 			/*
347 			 * Only write out uncorrupted lines
348 			 */
349 			if (octets <= 0) {
350 				(void) fwrite(inbuf, n, 1, out);
351 			}
352 		}
353 	} else {	/* use base64 algorithm */
354 		endseen = numbase64chars = 0;
355 		optr = outbuf;
356 		while ((fgets(inbuf, sizeof (inbuf), in)) != NULL) {
357 			/* process an input line */
358 			iptr = inbuf;
359 			while ((curchr = *(iptr++)) != NULL) {
360 				/* decode chars */
361 				if (curchr == '=') /* if end */
362 					endseen++;
363 
364 				if (validbase64(curchr))
365 					chr[numbase64chars++] = curchr;
366 				/*
367 				 * if we've gathered 4 base64 octets
368 				 * we need to decode and output them
369 				 */
370 				if (numbase64chars == 4) {
371 					/*LINTED*/
372 					if (optr - outbuf > BUFSIZE - 3) {
373 						(void) fwrite(outbuf,
374 						    /*LINTED*/
375 						    (size_t)(optr - outbuf),
376 						    1, out);
377 						if (ferror(out)) {
378 							perror(prog);
379 							exit(6);
380 						}
381 						optr = outbuf;
382 					}
383 					octets = outdec64(optr, chr, 4);
384 					optr += octets;
385 					numbase64chars = 0;
386 				}
387 			}
388 			/*
389 			 * handle any remaining base64 octets at end
390 			 */
391 			if (endseen && numbase64chars > 0) {
392 				octets = outdec64(optr, chr, numbase64chars);
393 				optr += octets;
394 				numbase64chars = 0;
395 			}
396 		}
397 		/*
398 		 * if we have generated any additional output
399 		 * in the buffer, write it out
400 		 */
401 		if (optr != outbuf) {
402 			/*LINTED*/
403 			(void) fwrite(outbuf, (size_t)(optr - outbuf),
404 			    1, out);
405 			if (ferror(out)) {
406 				perror(prog);
407 				exit(6);
408 			}
409 		}
410 
411 		if (endseen == 0) {
412 			(void) fprintf(stderr, gettext("No end line\n"));
413 			exit(5);
414 		}
415 	}
416 }
417 
418 /*
419  * historical algorithm
420  *
421  * output a group of 3 bytes (4 input characters).
422  * the input chars are pointed to by p, they are to
423  * be output to file f.  n is used to tell us not to
424  * output all of them at the end of the file.
425  */
426 
427 static int
outdec(unsigned char * out,unsigned char * in,int n)428 outdec(unsigned char *out, unsigned char *in, int n)
429 {
430 	unsigned char	b0 = DEC(*(in++));
431 	unsigned char	b1 = DEC(*(in++));
432 	unsigned char	b2 = DEC(*(in++));
433 	unsigned char	b3 = DEC(*in);
434 
435 	if (!isvalid(b0)) {
436 		return (*(in-3));
437 	}
438 	if (!isvalid(b1)) {
439 		return (*(in-2));
440 	}
441 
442 	*(out++) = (b0 << 2) | (b1 >> 4);
443 
444 	if (n >= 2) {
445 		if (!isvalid(b2)) {
446 			return (*(in - 1));
447 		}
448 
449 		*(out++) = (b1 << 4) | (b2 >> 2);
450 
451 		if (n >= 3) {
452 			if (!isvalid(b3)) {
453 				return (*in);
454 			}
455 			*out = (b2 << 6) | b3;
456 		}
457 	}
458 	return (0x20); /* a know good value */
459 }
460 
461 /*
462  * base64 algorithm
463  *
464  * Takes a pointer to the current position in the output buffer,
465  * a pointer to the (up to) 4 byte base64 input buffer and a
466  * count of the number of valid input bytes.
467  *
468  * Return the number of bytes placed in the output buffer
469  */
470 static int
outdec64(unsigned char * out,unsigned char * chr,int num)471 outdec64(unsigned char *out, unsigned char *chr, int num)
472 {
473 
474 	unsigned char char1, char2, char3, char4;
475 	unsigned char *outptr = out;
476 	int rc = 0;
477 
478 	switch (num) {
479 	case 0:
480 	case 1: 	/* these are impossible */
481 	default:
482 		break;
483 	case 2:		/* 2 base64 bytes == 1 decoded byte */
484 		char1 = base64tab[chr[0]] & 0xFF;
485 		char2 = base64tab[chr[1]] & 0xFF;
486 		*(outptr++) = ((char1 << 2) & 0xFC) |
487 		    ((char2 >> 4) & 0x03);
488 		rc = 1;
489 		break;
490 	case 3:		/* 3 base64 bytes == 2 decoded bytes */
491 		char1 = base64tab[chr[0]] & 0xFF;
492 		char2 = base64tab[chr[1]] & 0xFF;
493 		char3 = base64tab[chr[2]] & 0xFF;
494 		*(outptr++) = ((char1 << 2) & 0xFC) |
495 		    ((char2 >> 4) & 0x03);
496 		*(outptr++) = ((char2 << 4) & 0xF0) |
497 		    ((char3 >> 2) & 0x0F);
498 		rc = 2;
499 		break;
500 	case 4:		/* 4 base64 bytes == 3 decoded bytes */
501 		char1 = base64tab[chr[0]] & 0xFF;
502 		char2 = base64tab[chr[1]] & 0xFF;
503 		char3 = base64tab[chr[2]] & 0xFF;
504 		char4 = base64tab[chr[3]] & 0xFF;
505 		*(outptr++) = ((char1 << 2) & 0xFC) |
506 		    ((char2 >> 4) & 0x03);
507 		*(outptr++) = ((char2 << 4) & 0xF0) |
508 		    ((char3 >> 2) & 0x0F);
509 		*(outptr++) = ((char3 << 6) & 0xC0) |
510 		    (char4 & 0x3F);
511 		rc = 3;
512 		break;
513 	}
514 	return (rc);
515 }
516 
517 /*
518  * error message routine called by newmode.
519  *
520  * The severity and code are ignored here.  If this routine gets
521  * called, we set a global flag (which can be tested after return
522  * from here) which tells us whether or not a valid mode has been
523  * parsed or if we printed an error message.
524  */
525 
526 /*ARGSUSED*/
527 void
errmsg(int severity,int code,char * format,...)528 errmsg(int severity, int code, char *format, ...)
529 {
530 	va_list ap;
531 
532 	va_start(ap, format);
533 
534 	(void) fprintf(stderr, "uudecode: ");
535 	(void) fprintf(stderr, format, ap);
536 
537 	va_end(ap);
538 
539 	mode_err = 1;
540 }
541