freebsd-src/usr.bin/bsdiff/bspatch/bspatch.c
Pedro F. Giffuni 1de7b4b805 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

301 lines
8.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright 2003-2005 Colin Percival
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if defined(__FreeBSD__)
#include <sys/param.h>
#if __FreeBSD_version >= 1001511
#include <sys/capsicum.h>
#define HAVE_CAPSICUM
#endif
#endif
#include <bzlib.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <libgen.h>
#include <limits.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#ifndef O_BINARY
#define O_BINARY 0
#endif
#define HEADER_SIZE 32
static char *newfile;
static int dirfd = -1;
static void
exit_cleanup(void)
{
if (dirfd != -1 && newfile != NULL)
if (unlinkat(dirfd, newfile, 0))
warn("unlinkat");
}
static off_t offtin(u_char *buf)
{
off_t y;
y = buf[7] & 0x7F;
y = y * 256; y += buf[6];
y = y * 256; y += buf[5];
y = y * 256; y += buf[4];
y = y * 256; y += buf[3];
y = y * 256; y += buf[2];
y = y * 256; y += buf[1];
y = y * 256; y += buf[0];
if (buf[7] & 0x80)
y = -y;
return (y);
}
static void
usage(void)
{
fprintf(stderr, "usage: bspatch oldfile newfile patchfile\n");
exit(1);
}
int main(int argc, char *argv[])
{
FILE *f, *cpf, *dpf, *epf;
BZFILE *cpfbz2, *dpfbz2, *epfbz2;
char *directory, *namebuf;
int cbz2err, dbz2err, ebz2err;
int newfd, oldfd;
off_t oldsize, newsize;
off_t bzctrllen, bzdatalen;
u_char header[HEADER_SIZE], buf[8];
u_char *old, *new;
off_t oldpos, newpos;
off_t ctrl[3];
off_t i, lenread, offset;
#ifdef HAVE_CAPSICUM
cap_rights_t rights_dir, rights_ro, rights_wr;
#endif
if (argc != 4)
usage();
/* Open patch file */
if ((f = fopen(argv[3], "rb")) == NULL)
err(1, "fopen(%s)", argv[3]);
/* Open patch file for control block */
if ((cpf = fopen(argv[3], "rb")) == NULL)
err(1, "fopen(%s)", argv[3]);
/* open patch file for diff block */
if ((dpf = fopen(argv[3], "rb")) == NULL)
err(1, "fopen(%s)", argv[3]);
/* open patch file for extra block */
if ((epf = fopen(argv[3], "rb")) == NULL)
err(1, "fopen(%s)", argv[3]);
/* open oldfile */
if ((oldfd = open(argv[1], O_RDONLY | O_BINARY, 0)) < 0)
err(1, "open(%s)", argv[1]);
/* open directory where we'll write newfile */
if ((namebuf = strdup(argv[2])) == NULL ||
(directory = dirname(namebuf)) == NULL ||
(dirfd = open(directory, O_DIRECTORY)) < 0)
err(1, "open %s", argv[2]);
free(namebuf);
if ((newfile = basename(argv[2])) == NULL)
err(1, "basename");
/* open newfile */
if ((newfd = openat(dirfd, newfile,
O_CREAT | O_TRUNC | O_WRONLY | O_BINARY, 0666)) < 0)
err(1, "open(%s)", argv[2]);
atexit(exit_cleanup);
#ifdef HAVE_CAPSICUM
if (cap_enter() < 0) {
/* Failed to sandbox, fatal if CAPABILITY_MODE enabled */
if (errno != ENOSYS)
err(1, "failed to enter security sandbox");
} else {
/* Capsicum Available */
cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK);
cap_rights_init(&rights_wr, CAP_WRITE);
cap_rights_init(&rights_dir, CAP_UNLINKAT);
if (cap_rights_limit(fileno(f), &rights_ro) < 0 ||
cap_rights_limit(fileno(cpf), &rights_ro) < 0 ||
cap_rights_limit(fileno(dpf), &rights_ro) < 0 ||
cap_rights_limit(fileno(epf), &rights_ro) < 0 ||
cap_rights_limit(oldfd, &rights_ro) < 0 ||
cap_rights_limit(newfd, &rights_wr) < 0 ||
cap_rights_limit(dirfd, &rights_dir) < 0)
err(1, "cap_rights_limit() failed, could not restrict"
" capabilities");
}
#endif
/*
File format:
0 8 "BSDIFF40"
8 8 X
16 8 Y
24 8 sizeof(newfile)
32 X bzip2(control block)
32+X Y bzip2(diff block)
32+X+Y ??? bzip2(extra block)
with control block a set of triples (x,y,z) meaning "add x bytes
from oldfile to x bytes from the diff block; copy y bytes from the
extra block; seek forwards in oldfile by z bytes".
*/
/* Read header */
if (fread(header, 1, HEADER_SIZE, f) < HEADER_SIZE) {
if (feof(f))
errx(1, "Corrupt patch");
err(1, "fread(%s)", argv[3]);
}
/* Check for appropriate magic */
if (memcmp(header, "BSDIFF40", 8) != 0)
errx(1, "Corrupt patch");
/* Read lengths from header */
bzctrllen = offtin(header + 8);
bzdatalen = offtin(header + 16);
newsize = offtin(header + 24);
if (bzctrllen < 0 || bzctrllen > OFF_MAX - HEADER_SIZE ||
bzdatalen < 0 || bzctrllen + HEADER_SIZE > OFF_MAX - bzdatalen ||
newsize < 0 || newsize > SSIZE_MAX)
errx(1, "Corrupt patch");
/* Close patch file and re-open it via libbzip2 at the right places */
if (fclose(f))
err(1, "fclose(%s)", argv[3]);
offset = HEADER_SIZE;
if (fseeko(cpf, offset, SEEK_SET))
err(1, "fseeko(%s, %jd)", argv[3], (intmax_t)offset);
if ((cpfbz2 = BZ2_bzReadOpen(&cbz2err, cpf, 0, 0, NULL, 0)) == NULL)
errx(1, "BZ2_bzReadOpen, bz2err = %d", cbz2err);
offset += bzctrllen;
if (fseeko(dpf, offset, SEEK_SET))
err(1, "fseeko(%s, %jd)", argv[3], (intmax_t)offset);
if ((dpfbz2 = BZ2_bzReadOpen(&dbz2err, dpf, 0, 0, NULL, 0)) == NULL)
errx(1, "BZ2_bzReadOpen, bz2err = %d", dbz2err);
offset += bzdatalen;
if (fseeko(epf, offset, SEEK_SET))
err(1, "fseeko(%s, %jd)", argv[3], (intmax_t)offset);
if ((epfbz2 = BZ2_bzReadOpen(&ebz2err, epf, 0, 0, NULL, 0)) == NULL)
errx(1, "BZ2_bzReadOpen, bz2err = %d", ebz2err);
if ((oldsize = lseek(oldfd, 0, SEEK_END)) == -1 ||
oldsize > SSIZE_MAX ||
(old = malloc(oldsize)) == NULL ||
lseek(oldfd, 0, SEEK_SET) != 0 ||
read(oldfd, old, oldsize) != oldsize ||
close(oldfd) == -1)
err(1, "%s", argv[1]);
if ((new = malloc(newsize)) == NULL)
err(1, NULL);
oldpos = 0;
newpos = 0;
while (newpos < newsize) {
/* Read control data */
for (i = 0; i <= 2; i++) {
lenread = BZ2_bzRead(&cbz2err, cpfbz2, buf, 8);
if ((lenread < 8) || ((cbz2err != BZ_OK) &&
(cbz2err != BZ_STREAM_END)))
errx(1, "Corrupt patch");
ctrl[i] = offtin(buf);
}
/* Sanity-check */
if (ctrl[0] < 0 || ctrl[0] > INT_MAX ||
ctrl[1] < 0 || ctrl[1] > INT_MAX)
errx(1, "Corrupt patch");
/* Sanity-check */
if (newpos + ctrl[0] > newsize)
errx(1, "Corrupt patch");
/* Read diff string */
lenread = BZ2_bzRead(&dbz2err, dpfbz2, new + newpos, ctrl[0]);
if ((lenread < ctrl[0]) ||
((dbz2err != BZ_OK) && (dbz2err != BZ_STREAM_END)))
errx(1, "Corrupt patch");
/* Add old data to diff string */
for (i = 0; i < ctrl[0]; i++)
if ((oldpos + i >= 0) && (oldpos + i < oldsize))
new[newpos + i] += old[oldpos + i];
/* Adjust pointers */
newpos += ctrl[0];
oldpos += ctrl[0];
/* Sanity-check */
if (newpos + ctrl[1] > newsize)
errx(1, "Corrupt patch");
/* Read extra string */
lenread = BZ2_bzRead(&ebz2err, epfbz2, new + newpos, ctrl[1]);
if ((lenread < ctrl[1]) ||
((ebz2err != BZ_OK) && (ebz2err != BZ_STREAM_END)))
errx(1, "Corrupt patch");
/* Adjust pointers */
newpos+=ctrl[1];
oldpos+=ctrl[2];
}
/* Clean up the bzip2 reads */
BZ2_bzReadClose(&cbz2err, cpfbz2);
BZ2_bzReadClose(&dbz2err, dpfbz2);
BZ2_bzReadClose(&ebz2err, epfbz2);
if (fclose(cpf) || fclose(dpf) || fclose(epf))
err(1, "fclose(%s)", argv[3]);
/* Write the new file */
if (write(newfd, new, newsize) != newsize || close(newfd) == -1)
err(1, "%s", argv[2]);
/* Disable atexit cleanup */
newfile = NULL;
free(new);
free(old);
return (0);
}