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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "conf.h"
int main(int argc, char* const argv[])
{
if (argc < 6)
{
fprintf(stderr, "usage: %s <uid> <jail> <cwd> <interp> <script> [args...]\n", argv[0]);
exit(1);
}
if (strlen(argv[2]) < 1 || argv[2][0] != '/'
|| strstr(argv[2], "/..")
|| strncmp(argv[2], jail_base, strlen(jail_base)))
{
fprintf(stderr, "bad path: %s\n", argv[2]);
exit(1);
}
if (chroot(argv[2]))
{
perror("could not chroot");
exit(1);
}
if (chdir(argv[3]))
{
perror("could not chdir");
exit(1);
}
if (setuid(atoi(argv[1])))
{
perror("could not setuid");
exit(1);
}
execv(argv[4], argv + 5);
/* nb exec won't return unless there was an error */
perror("could not exec");
exit(1);
}
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