uudecode.c revision 103204 
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
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#if 0
41#ifndef lint
42static char sccsid[] = "@(#)uudecode.c	8.2 (Berkeley) 4/2/94";
43#endif /* not lint */
44#endif
45
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD: head/usr.bin/uudecode/uudecode.c 103204 2002-09-10 21:14:14Z fanf $");
48
49/*
50 * uudecode [file ...]
51 *
52 * create the specified file, decoding as you go.
53 * used with uuencode.
54 */
55#include <sys/param.h>
56#include <sys/socket.h>
57#include <sys/stat.h>
58
59#include <netinet/in.h>
60
61#include <err.h>
62#include <pwd.h>
63#include <resolv.h>
64#include <stdio.h>
65#include <stdlib.h>
66#include <string.h>
67#include <unistd.h>
68
69const char *filename;
70char *outfile;
71int cflag, iflag, oflag, pflag, sflag;
72
73static void usage(void);
74int	decode(void);
75int	decode2(void);
76int	base64_decode(const char *);
77
78int
79main(int argc, char *argv[])
80{
81	int rval, ch;
82
83	while ((ch = getopt(argc, argv, "cio:ps")) != -1) {
84		switch(ch) {
85		case 'c':
86			if (oflag)
87				usage();
88			cflag = 1; /* multiple uudecode'd files */
89			break;
90		case 'i':
91			iflag = 1; /* ask before override files */
92			break;
93		case 'o':
94			if (cflag || pflag || 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 's':
106			if (oflag)
107				usage();
108			sflag = 1; /* do not strip pathnames for output */
109			break;
110		default:
111			usage();
112		}
113	}
114        argc -= optind;
115        argv += optind;
116
117	if (*argv) {
118		rval = 0;
119		do {
120			if (freopen(filename = *argv, "r", stdin) == NULL) {
121				warn("%s", *argv);
122				rval = 1;
123				continue;
124			}
125			rval |= decode();
126		} while (*++argv);
127	} else {
128		filename = "stdin";
129		rval = decode();
130	}
131	exit(rval);
132}
133
134int
135decode(void)
136{
137	int r, v;
138
139	v = decode2();
140	if (v == EOF) {
141		warnx("%s: missing or bad \"begin\" line", filename);
142		return (1);
143	}
144	for (r = v; cflag; r |= v) {
145		v = decode2();
146		if (v == EOF)
147			break;
148	}
149	return (r);
150}
151
152int
153decode2(void)
154{
155	int base64;
156	int n;
157	char ch, *p, *q;
158	void *mode;
159	struct passwd *pw;
160	struct stat st;
161	char buf[MAXPATHLEN+1];
162	char buffn[MAXPATHLEN+1]; /* file name buffer */
163
164	base64 = 0;
165	/* search for header line */
166	for (;;) {
167		if (fgets(buf, sizeof(buf), stdin) == NULL)
168			return (EOF);
169		p = buf;
170		if (strncmp(p, "begin-base64 ", 13) == 0) {
171			base64 = 1;
172			p += 13;
173		} else if (strncmp(p, "begin ", 6) == 0)
174			p += 6;
175		else
176			continue;
177		/* p points to mode */
178		q = strchr(p, ' ');
179		if (q == NULL)
180			continue;
181		*q++ = '\0';
182		/* q points to filename */
183		n = strlen(q);
184		while (n > 0 && (q[n-1] == '\n' || q[n-1] == '\r'))
185			q[--n] = '\0';
186		/* found valid header? */
187		if (n > 0)
188			break;
189	}
190
191	mode = setmode(p);
192	if (mode == NULL) {
193		warnx("%s: unable to parse file mode", filename);
194		return (1);
195	}
196
197	if (oflag) {
198		/* use command-line filename */
199		n = strlcpy(buffn, outfile, sizeof(buffn));
200	} else if (sflag) {
201		/* don't strip, so try ~user/file expansion */
202		p = NULL;
203		pw = NULL;
204		if (*q == '~')
205			p = strchr(q, '/');
206		if (p != NULL) {
207			*p = '\0';
208			pw = getpwnam(q + 1);
209			*p = '/';
210		}
211		if (pw != NULL) {
212			strlcpy(buffn, pw->pw_dir, sizeof(buffn));
213			n = strlcat(buffn, p, sizeof(buffn));
214		} else {
215			n = strlcpy(buffn, q, sizeof(buffn));
216		}
217	} else {
218		/* strip down to leaf name */
219		p = strrchr(q, '/');
220		if (p != NULL)
221			n = strlcpy(buffn, p+1, sizeof(buffn));
222		else
223			n = strlcpy(buffn, q, sizeof(buffn));
224	}
225	if (n >= sizeof(buffn) || *buffn == '\0') {
226		warnx("%s: bad output filename", filename);
227		return (1);
228	}
229
230	if (!pflag) {
231		if (iflag && !access(buffn, F_OK)) {
232			warnx("not overwritten: %s", buffn);
233			return (0);
234		}
235		if (freopen(buffn, "w", stdout) == NULL ||
236		    stat(buffn, &st) < 0 || (S_ISREG(st.st_mode) &&
237		    fchmod(fileno(stdout), getmode(mode, 0) & 0666) < 0)) {
238			warn("%s: %s", filename, buffn);
239			return (1);
240		}
241	}
242	free(mode);
243
244	if (base64)
245		return (base64_decode(buffn));
246
247	/* for each input line */
248	for (;;) {
249		if (fgets(p = buf, sizeof(buf), stdin) == NULL) {
250			warnx("%s: short file", filename);
251			return (1);
252		}
253
254#define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
255#define IS_DEC(c) ( (((c) - ' ') >= 0) && (((c) - ' ') <= 077 + 1) )
256
257#define OUT_OF_RANGE do {						\
258	warnx("%s: %s: character out of range: [%d-%d]",		\
259	    filename, buffn, 1 + ' ', 077 + ' ' + 1);			\
260        return (1);							\
261} while (0)
262
263		/*
264		 * `n' is used to avoid writing out all the characters
265		 * at the end of the file.
266		 */
267		if ((n = DEC(*p)) <= 0)
268			break;
269		for (++p; n > 0; p += 4, n -= 3)
270			if (n >= 3) {
271				if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) &&
272				     IS_DEC(*(p + 2)) && IS_DEC(*(p + 3))))
273                                	OUT_OF_RANGE
274
275				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
276				putchar(ch);
277				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
278				putchar(ch);
279				ch = DEC(p[2]) << 6 | DEC(p[3]);
280				putchar(ch);
281			}
282			else {
283				if (n >= 1) {
284					if (!(IS_DEC(*p) && IS_DEC(*(p + 1))))
285	                                	OUT_OF_RANGE
286					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
287					putchar(ch);
288				}
289				if (n >= 2) {
290					if (!(IS_DEC(*(p + 1)) &&
291						IS_DEC(*(p + 2))))
292		                                OUT_OF_RANGE
293
294					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
295					putchar(ch);
296				}
297				if (n >= 3) {
298					if (!(IS_DEC(*(p + 2)) &&
299						IS_DEC(*(p + 3))))
300		                                OUT_OF_RANGE
301					ch = DEC(p[2]) << 6 | DEC(p[3]);
302					putchar(ch);
303				}
304			}
305	}
306	if (fgets(buf, sizeof(buf), stdin) == NULL ||
307	    (strcmp(buf, "end") && strcmp(buf, "end\n") &&
308	     strcmp(buf, "end\r\n"))) {
309		warnx("%s: no \"end\" line", filename);
310		return (1);
311	}
312	return (0);
313}
314
315int
316base64_decode(const char *outname)
317{
318	int n;
319	char buf[MAXPATHLEN+1];
320	unsigned char out[MAXPATHLEN * 4];
321
322	for (;;) {
323		if (fgets(buf, sizeof(buf), stdin) == NULL) {
324			warnx("%s: short file", filename);
325			return (1);
326		}
327		if (strcmp(buf, "====") == 0 ||
328		    strcmp(buf, "====\n") == 0 ||
329		    strcmp(buf, "====\r\n") == 0)
330			return (0);
331		n = strlen(buf);
332		while (n > 0 && (buf[n-1] == '\n' || buf[n-1] == '\r'))
333			buf[--n] = '\0';
334		n = b64_pton(buf, out, sizeof(out));
335		if (n < 0) {
336			warnx("%s: %s: error decoding base64 input stream", filename, outname);
337			return (1);
338		}
339		fwrite(out, 1, n, stdout);
340	}
341}
342
343static void
344usage(void)
345{
346	(void)fprintf(stderr,
347"usage: uudecode [-cips] [file ...]\n"
348"       uudecode [-i] -o output_file [file]\n"
349"       b64decode [-cips] [file ...]\n"
350"       b64decode [-i] -o output_file [file]\n");
351	exit(1);
352}
353