runasowner.c

/*
 * wrapper of running shell script as given user
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>

int main(int argc, char *argv[])
{
    if (argc != 2) {
        fprintf(stderr, "one argument required! script name(full path).\n");
        return 1;
    }
    int ret;
    char * script = argv[1];
    ret = setuid(1001);
    printf("ret: %d\n", ret);
    printf("getuid: %d, geteuid: %d\n", getuid(), geteuid());
    /* char *newenvp[] = { NULL }; */
    /* char *newargv[] = { script, NULL }; */
    /* execve(script, newargv, newenvp); */
    /* perror("execve"); */

    ret = execl("/usr/bin/bash", "/usr/bin/bash", script, (char *)0);
    printf("ret: %d", ret);
    return 0;
}

test.sh

#!/bin/sh

date
whoami
sleep 100