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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
static char *progname;
static char *xstrdup(const char *s)
{
char *t = strdup(s);
if (!t) {
fprintf(stderr, "%s: failed to allocate memory\n", progname);
exit(1);
}
return t;
}
static void *xrealloc(void *oldptr, size_t size)
{
void *ptr = realloc(oldptr, size);
if (!ptr) {
fprintf(stderr, "%s: failed to allocate memory\n", progname);
exit(1);
}
return ptr;
}
static void add_arg(char **cmdp, const char *opt)
{
size_t optlen = strlen(opt);
size_t cmdlen = *cmdp ? strlen(*cmdp) : 0;
char *cmd = xrealloc(*cmdp, cmdlen + optlen * 4 + 4);
char *s;
s = cmd + cmdlen;
if (*cmdp)
*s++ = ' ';
*s++ = '\'';
for (; *opt; opt++) {
if (*opt == '\'') {
*s++ = '\'';
*s++ = '\\';
*s++ = '\'';
*s++ = '\'';
} else
*s++ = *opt;
}
*s++ = '\'';
*s = '\0';
*cmdp = cmd;
}
int main(int argc, char *argv[])
{
char *type;
char *source;
const char *mountpoint;
char *options = NULL;
char *command = NULL;
char *setuid = NULL;
int i;
progname = argv[0];
if (argc < 3) {
fprintf(stderr,
"usage: %s type#[source] mountpoint [-o opt[,opts...]]\n",
progname);
exit(1);
}
type = xstrdup(argv[1]);
source = strchr(type, '#');
if (source)
*source++ = '\0';
if (!type[0]) {
fprintf(stderr, "%s: empty filesystem type\n", progname);
exit(1);
}
mountpoint = argv[2];
for (i = 3; i < argc; i++) {
if (strcmp(argv[i], "-v") == 0)
continue;
if (strcmp(argv[i], "-o") == 0) {
char *opts;
char *opt;
i++;
if (i == argc)
break;
opts = xstrdup(argv[i]);
opt = strtok(opts, ",");
while (opt) {
int j;
int ignore = 0;
const char *ignore_opts[] = { "", "user", "nouser", "users",
"auto", "noauto", "_netdev",
NULL};
if (strncmp(opt, "setuid=", 7) == 0) {
setuid = xstrdup(opt + 7);
ignore = 1;
}
for (j = 0; ignore_opts[j]; j++)
if (strcmp(opt, ignore_opts[j]) == 0)
ignore = 1;
if (!ignore) {
int oldlen = options ? strlen(options) : 0;
options = xrealloc(options, oldlen + 1 + strlen(opt) + 1);
if (!oldlen)
strcpy(options, opt);
else {
strcat(options, ",");
strcat(options, opt);
}
}
opt = strtok(NULL, ",");
}
}
}
add_arg(&command, type);
if (source)
add_arg(&command, source);
add_arg(&command, mountpoint);
if (options) {
add_arg(&command, "-o");
add_arg(&command, options);
}
if (setuid && setuid[0]) {
char *sucommand = command;
command = NULL;
add_arg(&command, "su");
add_arg(&command, "-");
add_arg(&command, setuid);
add_arg(&command, "-c");
add_arg(&command, sucommand);
} else if (!getenv("HOME")) {
/* Hack to make filesystems work in the boot environment */
setenv("HOME", "/root", 0);
}
execl("/bin/sh", "/bin/sh", "-c", command, NULL);
fprintf(stderr, "%s: failed to execute /bin/sh: %s\n", progname,
strerror(errno));
return 1;
}
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