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/* Copyright (c) 1999 Anthony Towns
* Copyright (c) 2000, 2002 Matthias Klose
* Copyright (c) 2008 Canonical Ltd
*
* You may freely use, distribute, and modify this program.
*/
// Don't rely on /bin/sh and popen!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <limits.h>
#include <sys/types.h>
#include <sys/wait.h>
/* XXX: evil kludge, deal with arbitrary name lengths */
#ifndef PATH_MAX
#define PATH_MAX 4096
#endif
#include "md5.h"
int check_predepends(void)
{
pid_t child;
switch(child = fork()) {
case -1:
/* fork failed */
return EXIT_FAILURE;
case 0:
/* i'm the child */
{
execl( "/usr/bin/dpkg", "/usr/bin/dpkg",
"--assert-support-predepends", NULL );
_exit(127);
}
default:
/* i'm the parent */
{
int status;
pid_t pid;
pid = wait(&status);
if (pid == child) {
if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
return EXIT_SUCCESS;
}
}
}
}
return EXIT_FAILURE;
}
#define BUFSIZE 8192
int md5sum_match(char *fn, char* fn_digest)
{
md5_state_t md5;
md5_byte_t digest[16];
unsigned char hexdigest[33];
int i, j, fd;
size_t nbytes;
md5_byte_t buf[BUFSIZE];
// if not existant, md5sums don't match
if (access(fn, R_OK))
return 0;
if ((fd = open(fn, O_RDONLY)) == -1)
return 0;
md5_init(&md5);
while (nbytes = read(fd, buf, BUFSIZE))
md5_append(&md5, buf, nbytes);
md5_finish(&md5, digest);
close(fd);
for (i = j = 0; i < 16; i++) {
unsigned char c;
c = (digest[i] >> 4) & 0xf;
c = (c > 9) ? c + 'a' - 10 : c + '0';
hexdigest[j++] = c;
c = (digest[i] & 0xf);
c = (c > 9) ? c + 'a' - 10 : c + '0';
hexdigest[j++] = c;
}
hexdigest[j] = '\0';
#ifdef NDEBUG
fprintf(stderr, "fn=%s, md5sum=%s, expected=%s\n", fn, hexdigest, fn_digest);
#endif
return !strcmp(fn_digest, hexdigest);
}
int unmodified_file(char *fn, int md5sumc, unsigned char* md5sumv[])
{
int i;
// if not existant, pretend its unmodified
if (access(fn, R_OK))
return 1;
for (i = 0; i < md5sumc; i++) {
if (md5sum_match(fn, md5sumv[i]))
return 1;
}
return 0;
}
unsigned char *md5sumv_bash_profile[] = {
"d1a8c44e7dd1bed2f3e75d1343b6e4e1", // dapper, edgy, etch
"0bc1802860b758732b862ef973cd79ff", // feisty, gutsy
};
const int md5sumc_bash_profile = sizeof(md5sumv_bash_profile) / sizeof (char *);
unsigned char *md5sumv_profile[] = {
"7d97942254c076a2ea5ea72180266420", // feisty, gutsy
};
const int md5sumc_profile = sizeof(md5sumv_profile) / sizeof (char *);
#ifdef BC_CONFIG
unsigned char *md5sumv_completion[] = {
"2bc0b6cf841eefd31d607e618f1ae29d", // dapper
"ae1d298e51ea7f8253eea8b99333561f", // edgy
"adc2e9fec28bd2d4a720e725294650f0", // feisty
"c8bce25ea68fb0312579a421df99955c", // gutsy, and last one in bash
"9da8d1c95748865d516764fb9af82af9", // etch, sid (last one in bash)
};
const int md5sumc_completion = sizeof(md5sumv_completion) / sizeof (char *);
#endif
char *check_diversion(void)
{
pid_t child;
int pipedes[2];
if (pipe(pipedes))
return NULL;
switch(child = fork()) {
case -1:
/* fork failed */
close(pipedes[0]);
close(pipedes[1]);
return NULL;
case 0:
/* i'm the child */
{
if (dup2(pipedes[STDOUT_FILENO], STDOUT_FILENO) < 0)
_exit(127);
close(pipedes[STDIN_FILENO]);
close(pipedes[STDOUT_FILENO]);
execl( "/usr/sbin/dpkg-divert", "/usr/sbin/dpkg-divert",
"--list", "/bin/sh", NULL );
_exit(127);
}
default:
/* i'm the parent */
{
static char line[1024];
FILE *fd;
close (pipedes[STDOUT_FILENO]);
fcntl (pipedes[STDIN_FILENO], F_SETFD, FD_CLOEXEC);
fd = fdopen (pipedes[STDIN_FILENO], "r");
while (fgets(line, 1024, fd) != NULL) {
line[strlen(line)-1] = '\0';
break;
}
fclose(fd);
return line;
}
}
return NULL;
}
const char *msg =
"As bash for Debian is destined to provide a working /bin/sh (pointing to\n"
"/bin/bash) your link will be overwritten by a default link.\n\n"
"If you don't want further upgrades to overwrite your customization, please\n"
"read /usr/share/doc/bash/README.Debian.gz for a more permanent solution.\n\n"
"[Press RETURN to continue]";
int main(void) {
int targetlen;
char target[PATH_MAX+1], answer[1024], *fn;
fn = "/etc/skel/.bash_profile";
if (!access(fn, R_OK)) {
if (unmodified_file(fn, md5sumc_bash_profile, md5sumv_bash_profile)) {
printf("removing %s in favour of /etc/skel/.profile\n", fn);
unlink(fn);
}
else {
fn = "/etc/skel/.profile";
if (!access(fn, R_OK)) {
if (unmodified_file(fn, md5sumc_profile, md5sumv_profile)) {
printf("renaming /etc/skel/.bash_profile to %s\n", fn);
rename("/etc/skel/.bash_profile", fn);
}
}
}
}
#ifdef BC_CONFIG
fn = "/etc/bash_completion";
if (!access(fn, R_OK)) {
if (unmodified_file(fn, md5sumc_completion, md5sumv_completion)) {
printf("removing unmodified %s, now in package bash-completion\n", fn);
unlink(fn);
}
}
#endif
if (check_predepends() != EXIT_SUCCESS) {
printf("\nPlease upgrade to a new version of dpkg\n\n");
return EXIT_FAILURE;
}
targetlen = readlink("/bin/sh", target, PATH_MAX);
if (targetlen == -1) {
// error reading link. Will be overwritten.
puts("The bash upgrade discovered that something is wrong with your /bin/sh link.");
puts(msg);
fgets(answer, 1024, stdin);
return EXIT_SUCCESS;
}
target[targetlen] = '\0';
if (strcmp(target, "bash") != 0 && strcmp(target, "/bin/bash") != 0) {
char *diversion = check_diversion();
if (diversion == NULL)
return EXIT_FAILURE;
// printf("diversion: /%s/\n", diversion);
if (strcmp(diversion, "") != 0)
// link is diverted
return EXIT_SUCCESS;
printf("The bash upgrade discovered that your /bin/sh link points to %s.\n", target);
puts(msg);
fgets(answer, 1024, stdin);
return EXIT_SUCCESS;
}
return EXIT_SUCCESS;
}
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