uudecode.c revision 106274 
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 106274 2002-11-01 00:29:00Z 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;
71FILE *infp, *outfp;
72int cflag, iflag, oflag, pflag, sflag;
73
74static void usage(void);
75int	decode(void);
76int	decode2(void);
77int	base64_decode(const char *);
78
79int
80main(int argc, char *argv[])
81{
82	int rval, ch;
83
84	while ((ch = getopt(argc, argv, "cio:ps")) != -1) {
85		switch(ch) {
86		case 'c':
87			if (oflag)
88				usage();
89			cflag = 1; /* multiple uudecode'd files */
90			break;
91		case 'i':
92			iflag = 1; /* ask before override files */
93			break;
94		case 'o':
95			if (cflag || pflag || sflag)
96				usage();
97			oflag = 1; /* output to the specified file */
98			sflag = 1; /* do not strip pathnames for output */
99			outfile = optarg; /* set the output filename */
100			break;
101		case 'p':
102			if (oflag)
103				usage();
104			pflag = 1; /* print output to stdout */
105			break;
106		case 's':
107			if (oflag)
108				usage();
109			sflag = 1; /* do not strip pathnames for output */
110			break;
111		default:
112			usage();
113		}
114	}
115        argc -= optind;
116        argv += optind;
117
118	if (*argv) {
119		rval = 0;
120		do {
121			infp = fopen(filename = *argv, "r");
122			if (infp == NULL) {
123				warn("%s", *argv);
124				rval = 1;
125				continue;
126			}
127			rval |= decode();
128			fclose(infp);
129		} while (*++argv);
130	} else {
131		filename = "stdin";
132		infp = stdin;
133		rval = decode();
134	}
135	exit(rval);
136}
137
138int
139decode(void)
140{
141	int r, v;
142
143	v = decode2();
144	if (v == EOF) {
145		warnx("%s: missing or bad \"begin\" line", filename);
146		return (1);
147	}
148	for (r = v; cflag; r |= v) {
149		v = decode2();
150		if (v == EOF)
151			break;
152	}
153	return (r);
154}
155
156int
157decode2(void)
158{
159	int base64, i;
160	size_t n;
161	char ch, *p, *q;
162	void *mode;
163	struct passwd *pw;
164	struct stat st;
165	char buf[MAXPATHLEN+1];
166	char buffn[MAXPATHLEN+1]; /* file name buffer */
167
168	base64 = 0;
169	/* search for header line */
170	for (;;) {
171		if (fgets(buf, sizeof(buf), infp) == NULL)
172			return (EOF);
173		p = buf;
174		if (strncmp(p, "begin-base64 ", 13) == 0) {
175			base64 = 1;
176			p += 13;
177		} else if (strncmp(p, "begin ", 6) == 0)
178			p += 6;
179		else
180			continue;
181		/* p points to mode */
182		q = strchr(p, ' ');
183		if (q == NULL)
184			continue;
185		*q++ = '\0';
186		/* q points to filename */
187		n = strlen(q);
188		while (n > 0 && (q[n-1] == '\n' || q[n-1] == '\r'))
189			q[--n] = '\0';
190		/* found valid header? */
191		if (n > 0)
192			break;
193	}
194
195	mode = setmode(p);
196	if (mode == NULL) {
197		warnx("%s: unable to parse file mode", filename);
198		return (1);
199	}
200
201	if (oflag) {
202		/* use command-line filename */
203		n = strlcpy(buffn, outfile, sizeof(buffn));
204	} else if (sflag) {
205		/* don't strip, so try ~user/file expansion */
206		p = NULL;
207		pw = NULL;
208		if (*q == '~')
209			p = strchr(q, '/');
210		if (p != NULL) {
211			*p = '\0';
212			pw = getpwnam(q + 1);
213			*p = '/';
214		}
215		if (pw != NULL) {
216			strlcpy(buffn, pw->pw_dir, sizeof(buffn));
217			n = strlcat(buffn, p, sizeof(buffn));
218		} else {
219			n = strlcpy(buffn, q, sizeof(buffn));
220		}
221	} else {
222		/* strip down to leaf name */
223		p = strrchr(q, '/');
224		if (p != NULL)
225			n = strlcpy(buffn, p+1, sizeof(buffn));
226		else
227			n = strlcpy(buffn, q, sizeof(buffn));
228	}
229	if (n >= sizeof(buffn) || *buffn == '\0') {
230		warnx("%s: bad output filename", filename);
231		return (1);
232	}
233
234	if (!pflag) {
235		if (iflag && !access(buffn, F_OK)) {
236			warnx("not overwritten: %s", buffn);
237			return (0);
238		}
239		if ((outfp = fopen(buffn, "w")) == NULL ||
240		    stat(buffn, &st) < 0 || (S_ISREG(st.st_mode) &&
241		    fchmod(fileno(outfp), getmode(mode, 0) & 0666) < 0)) {
242			warn("%s: %s", filename, buffn);
243			return (1);
244		}
245	}
246	free(mode);
247
248	if (base64)
249		return (base64_decode(buffn));
250
251	/* for each input line */
252	for (;;) {
253		if (fgets(p = buf, sizeof(buf), infp) == NULL) {
254			warnx("%s: short file", filename);
255			return (1);
256		}
257
258#define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
259#define IS_DEC(c) ( (((c) - ' ') >= 0) && (((c) - ' ') <= 077 + 1) )
260
261#define OUT_OF_RANGE do {						\
262	warnx("%s: %s: character out of range: [%d-%d]",		\
263	    filename, buffn, 1 + ' ', 077 + ' ' + 1);			\
264        return (1);							\
265} while (0)
266
267		/*
268		 * `i' is used to avoid writing out all the characters
269		 * at the end of the file.
270		 */
271		if ((i = DEC(*p)) <= 0)
272			break;
273		for (++p; i > 0; p += 4, i -= 3)
274			if (i >= 3) {
275				if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) &&
276				     IS_DEC(*(p + 2)) && IS_DEC(*(p + 3))))
277                                	OUT_OF_RANGE;
278
279				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
280				putc(ch, outfp);
281				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
282				putc(ch, outfp);
283				ch = DEC(p[2]) << 6 | DEC(p[3]);
284				putc(ch, outfp);
285			}
286			else {
287				if (i >= 1) {
288					if (!(IS_DEC(*p) && IS_DEC(*(p + 1))))
289	                                	OUT_OF_RANGE;
290					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
291					putc(ch, outfp);
292				}
293				if (i >= 2) {
294					if (!(IS_DEC(*(p + 1)) &&
295						IS_DEC(*(p + 2))))
296		                                OUT_OF_RANGE;
297
298					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
299					putc(ch, outfp);
300				}
301				if (i >= 3) {
302					if (!(IS_DEC(*(p + 2)) &&
303						IS_DEC(*(p + 3))))
304		                                OUT_OF_RANGE;
305					ch = DEC(p[2]) << 6 | DEC(p[3]);
306					putc(ch, outfp);
307				}
308			}
309	}
310	if (fgets(buf, sizeof(buf), infp) == NULL ||
311	    (strcmp(buf, "end") && strcmp(buf, "end\n") &&
312	     strcmp(buf, "end\r\n"))) {
313		warnx("%s: no \"end\" line", filename);
314		return (1);
315	}
316	if (fclose(outfp) != 0) {
317		warnx("%s: %s", filename, buffn);
318		return (1);
319	}
320	return (0);
321}
322
323int
324base64_decode(const char *outname)
325{
326	int n;
327	char buf[MAXPATHLEN+1];
328	unsigned char out[MAXPATHLEN * 4];
329
330	for (;;) {
331		if (fgets(buf, sizeof(buf), infp) == NULL) {
332			warnx("%s: short file", filename);
333			return (1);
334		}
335		if (strcmp(buf, "====") == 0 ||
336		    strcmp(buf, "====\n") == 0 ||
337		    strcmp(buf, "====\r\n") == 0)
338			return (0);
339		n = strlen(buf);
340		while (n > 0 && (buf[n-1] == '\n' || buf[n-1] == '\r'))
341			buf[--n] = '\0';
342		n = b64_pton(buf, out, sizeof(out));
343		if (n < 0) {
344			warnx("%s: %s: error decoding base64 input stream", filename, outname);
345			return (1);
346		}
347		fwrite(out, 1, n, outfp);
348	}
349}
350
351static void
352usage(void)
353{
354	(void)fprintf(stderr,
355"usage: uudecode [-cips] [file ...]\n"
356"       uudecode [-i] -o output_file [file]\n"
357"       b64decode [-cips] [file ...]\n"
358"       b64decode [-i] -o output_file [file]\n");
359	exit(1);
360}
361