Luna/apps/su.cpp

#include <os/ArgumentParser.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char** argv)
{
    StringView name;

    if (geteuid() != 0)
    {
        fprintf(stderr, "su must be run as root!\n");
        return 1;
    }

    os::ArgumentParser parser;
    parser.add_positional_argument(name, "name"_sv, true);
    parser.parse(argc, argv);

    struct passwd* entry = getpwnam(name.chars());
    if (!entry)
    {
        fprintf(stderr, "su: user %s not found!\n", name.chars());
        return 1;
    }

    if (getuid() != geteuid())
    {
        fprintf(stderr, "FIXME: you have to enter %s's password first!\n", name.chars());
        return 1;
    }

    setgid(entry->pw_gid);
    setuid(entry->pw_uid);

    execl(entry->pw_shell, entry->pw_shell, NULL);
}