NetBSD/usr.bin/uudecode/uudecode.c

324 lines
7.8 KiB
C

/* $NetBSD: uudecode.c,v 1.28 2013/01/28 19:50:30 apb Exp $ */
/*-
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif
#include <sys/cdefs.h>
#if !defined(lint)
__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
The Regents of the University of California. All rights reserved.");
#if 0
static char sccsid[] = "@(#)uudecode.c 8.2 (Berkeley) 4/2/94";
#endif
__RCSID("$NetBSD: uudecode.c,v 1.28 2013/01/28 19:50:30 apb Exp $");
#endif /* not lint */
/*
* uudecode [file ...]
*
* create the specified file, decoding as you go.
* used with uuencode.
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <locale.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifndef NO_BASE64
#include <netinet/in.h>
#include <resolv.h>
#endif
static int decode(char *);
__dead static void usage(void);
static int checkend(const char *, const char *, const char *);
static int base64_decode(void);
static int base64;
static const char *inputname;
int
main(int argc, char *argv[])
{
int ch, rval;
char *outputname = NULL;
setlocale(LC_ALL, "");
setprogname(argv[0]);
while ((ch = getopt(argc, argv, "mo:p")) != -1)
switch (ch) {
case 'm':
base64 = 1;
break;
case 'o':
outputname = optarg;
break;
case 'p':
outputname = __UNCONST("/dev/stdout");
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (*argv) {
rval = 0;
do {
if (!freopen(inputname = *argv, "r", stdin)) {
warn("%s", *argv);
rval = 1;
continue;
}
rval |= decode(outputname);
} while (*++argv);
} else {
inputname = "stdin";
rval = decode(outputname);
}
exit(rval);
}
/*
* Decode one file from stdin. If outputname is not NULL
* then it overrides the file name embedded in the input data.
*/
static int
decode(char *outputname)
{
struct passwd *pw;
int n;
char ch, *p;
int n1;
long mode;
char *fn;
char buf[MAXPATHLEN];
/* search for header line */
for (;;) {
if (!fgets(buf, sizeof(buf), stdin)) {
warnx("%s: no \"%s\" line", inputname, base64 ?
"begin-base64" : "begin");
return(1);
}
p = buf;
if (strncmp(p, "begin-base64", 12) == 0) {
base64 = 1;
p += 13;
break;
} else if (strncmp(p, "begin", 5) == 0) {
p += 6;
break;
} else
continue;
}
/* must be followed by an octal mode and a space */
mode = strtol(p, &fn, 8);
if (fn == (p) || !isspace((unsigned char)*fn) || mode==LONG_MIN || mode==LONG_MAX)
{
warnx("%s: invalid mode on \"%s\" line", inputname,
base64 ? "begin-base64" : "begin");
return(1);
}
/* skip whitespace for file name */
while (*fn && isspace((unsigned char)*fn)) fn++;
if (*fn == 0) {
warnx("%s: no filename on \"%s\" line", inputname,
base64 ? "begin-base64" : "begin");
return(1);
}
/* zap newline */
for (p = fn; *p && *p != '\n'; p++)
;
if (*p) *p = 0;
/* outputname overrides fn */
if (outputname)
fn = outputname;
/* handle ~user/file format */
if (*fn == '~') {
if (!(p = strchr(fn, '/'))) {
warnx("%s: illegal ~user.", inputname);
return(1);
}
*p++ = '\0';
if (!(pw = getpwnam(fn + 1))) {
warnx("%s: no user %s.", inputname, buf);
return(1);
}
n = strlen(pw->pw_dir);
n1 = strlen(p);
if (n + n1 + 2 > MAXPATHLEN) {
warnx("%s: path too long.", inputname);
return(1);
}
/* make space at beginning of buf by moving end of pathname */
memmove(buf + n + 1, p, n1 + 1);
memmove(buf, pw->pw_dir, n);
buf[n] = '/';
fn = buf;
}
if (strcmp(fn, "/dev/stdout") == 0 || strcmp(fn, "-") == 0) {
/*
* POSIX.1-2008 says that both "-" and "/dev/stdout"
* refer to standard output when they appear in the file
* header, but only "/dev/stdout" refers to standard
* output when it appears as the argument to the "-o"
* command line option.
*
* We handle both special names, regardless of whether
* they came from the "-o" option or from the header of
* the input stream.
*/
} else {
/*
* Create output file, and set its mode. POSIX.1-2008
* requires the mode to be used exactly, ignoring the
* umask and anything else, but we mask it with 0666.
*/
if (freopen(fn, "w", stdout) == NULL ||
fchmod(fileno(stdout), mode & 0666) != 0) {
warn("%s: %s", fn, inputname);
return(1);
}
}
if (base64)
return base64_decode();
else {
/* for each input line */
for (;;) {
if (!fgets(p = buf, sizeof(buf), stdin)) {
warnx("%s: short file.", inputname);
return(1);
}
#define DEC(c) (((c) - ' ') & 077) /* single character decode */
/*
* `n' is used to avoid writing out all the characters
* at the end of the file.
*/
if ((n = DEC(*p)) <= 0)
break;
for (++p; n > 0; p += 4, n -= 3)
if (n >= 3) {
ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
putchar(ch);
ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
putchar(ch);
ch = DEC(p[2]) << 6 | DEC(p[3]);
putchar(ch);
}
else {
if (n >= 1) {
ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
putchar(ch);
}
if (n >= 2) {
ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
putchar(ch);
}
if (n >= 3) {
ch = DEC(p[2]) << 6 | DEC(p[3]);
putchar(ch);
}
}
}
if (!fgets(buf, sizeof(buf), stdin) || strcmp(buf, "end\n")) {
warnx("%s: no \"end\" line.", inputname);
return(1);
}
return(0);
}
}
static int
checkend(const char *ptr, const char *end, const char *msg)
{
size_t n;
n = strlen(end);
if (strncmp(ptr, end, n) != 0 ||
strspn(ptr + n, "\t\r\n") != strlen(ptr + n)) {
warnx("%s", msg);
return (1);
}
return (0);
}
static int
base64_decode(void)
{
int n;
char inbuf[MAXPATHLEN];
unsigned char outbuf[MAXPATHLEN * 4];
for (;;) {
if (!fgets(inbuf, sizeof(inbuf), stdin)) {
warnx("%s: short file.", inputname);
return (1);
}
#ifdef NO_BASE64
warnx("%s: base64 decoding is not supported", inputname);
return (1);
#else
n = b64_pton(inbuf, outbuf, sizeof(outbuf));
#endif
if (n < 0)
break;
fwrite(outbuf, 1, n, stdout);
}
return (checkend(inbuf, "====",
"error decoding base64 input stream"));
}
static void
usage(void)
{
(void)fprintf(stderr,
"usage: %s [-m] [-p | -o outfile] [encoded-file ...]\n",
getprogname());
exit(1);
}