#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include <unistd.h>
#include <sys/types.h>
#include <sys/syscall.h>
#ifndef SYS_getresuid
uid_t cached_suid;
uid_t cached_sgid;
#endif
MODULE = Proc::UID PACKAGE = Proc::UID
PROTOTYPES: DISABLE
# Low-level calls to get our privileges.
# These *should* always return the same as $< and $>, $( and $)
int
geteuid()
CODE:
RETVAL = geteuid();
OUTPUT:
RETVAL
int
getruid()
CODE:
RETVAL = getuid();
OUTPUT:
RETVAL
int
getegid()
CODE:
RETVAL = getegid();
OUTPUT:
RETVAL
int
getrgid()
CODE:
RETVAL = getgid();
OUTPUT:
RETVAL
# Get our saved UID/GID
#ifdef SYS_getresuid
int
suid_is_cached()
CODE:
RETVAL = 0;
OUTPUT:
RETVAL
int
getsuid()
PREINIT:
int ret;
int ruid, euid, suid;
CODE:
ret = getresuid(&ruid, &euid, &suid);
if (ret == -1) {
croak("getresuid() returned failure. Error in Proc::UID?");
} else {
RETVAL = suid;
}
OUTPUT:
RETVAL
# Get our saved GID
int
getsgid()
PREINIT:
int ret;
int rgid, egid, sgid;
CODE:
ret = getresgid(&rgid, &egid, &sgid);
if (ret == -1) {
croak("getresgid() returned failure. Error in Proc::UID?");
} else {
RETVAL = sgid;
}
OUTPUT:
RETVAL
#else
# This records our saved privileges upon startup. Yes, this is
# is caching. I wish there were a better way.
int
suid_is_cached()
CODE:
RETVAL = 1;
OUTPUT:
RETVAL
void
init()
CODE:
cached_suid = geteuid();
cached_sgid = getegid();
int
getsuid()
CODE:
RETVAL = cached_suid;
OUTPUT:
RETVAL
int
getsgid()
CODE:
RETVAL = cached_sgid;
OUTPUT:
RETVAL
#endif
# Set our saved UID.
#ifdef SYS_setresuid
void
setsuid(suid)
int suid;
CODE:
if (setresuid(-1,-1,suid) == -1) {
croak("Could not set saved UID");
}
# Set our saved GID.
void
setsgid(sgid)
int sgid;
CODE:
if (setresgid(-1,-1,sgid) == -1) {
croak("Could not set saved GID");
}
#else
void
setsuid(suid)
int suid;
CODE:
croak("setsuid cannot run without setresuid, which is not on this system.");
void
setsgid(sgid)
int sgid;
CODE:
croak("setsgid cannot run without setresgid, which is not not on this system.");
#endif
# Preferred calls.
# drop_uid_temp - Drop privileges temporarily.
# Moves the current effective UID to the saved UID.
# Assigns the new_uid to the effective UID.
# Updates PL_euid
#ifdef SYS_setresuid
void
drop_uid_temp(new_uid)
int new_uid;
CODE:
if (setresuid(-1,new_uid,geteuid()) < 0) {
croak("Could not temporarily drop privs.");
}
if (geteuid() != new_uid) {
croak("Dropping privs appears to have failed.");
}
PL_euid = new_uid;
# else /* No setresuid() */
void
drop_uid_temp(new_uid)
int new_uid;
CODE:
int old_euid = geteuid();
# This looks like a no-op, but actually sets the
# SUID to the EUID. Or *should*.
if (setreuid(getruid(), old_euid) < 0) {
croak("Could not use setreuid with same privs.");
}
if (seteuid(new_uid) < 0) {
croak("Could not temporarily drop privs.");
}
if (geteuid() != new_uid) {
croak("Dropping privs appears to have failed.");
}
cached_suid = old_euid;
PL_euid = new_uid;
#endif /* setresuid */
# drop_uid_perm - Drop privileges permanently.
# Set all privileges to new_uid.
# Updates PL_uid and PL_euid
void
drop_uid_perm(new_uid)
int new_uid;
PREINIT:
int ruid, euid, suid;
CODE:
#ifdef SYS_setresuid
if (setresuid(new_uid,new_uid,new_uid) < 0) {
croak("Could not permanently drop privs.");
}
if (getresuid(&ruid, &euid, &suid) < 0) {
croak("Could not check privileges were dropped.");
}
if (ruid != new_uid || euid != new_uid || suid != new_uid) {
croak("Failed to drop privileges.");
}
#else
if (setreuid(new_uid, new_uid) < 0) {
croak("Could not permanently drop privs.");
}
# Having a way to read the SUID would be great,
# but depends upon the O/S.
# XXX - For the moment we just assume this works for SUID
if (getruid() != new_uid || geteuid() != new_uid) {
croak("Failed to drop privileges.");
}
cached_suid = new_uid;
#endif
PL_uid = new_uid;
PL_euid = new_uid;
void
restore_uid()
PREINIT:
int ruid, euid, suid;
CODE:
#ifdef SYS_setresuid
if (getresuid(&ruid, &euid, &suid) < 0) {
croak("Could not verify privileges.");
}
if (setresuid(-1,suid,-1) < 0) {
croak("Could not set effective UID.");
}
if (geteuid() != suid) {
croak("Failed to set effective UID.");
}
#else
if (seteuid(cached_suid) < 0) {
croak("Could not set effective UID.");
}
if (geteuid() != cached_suid) {
croak("Failed to set effective UID.");
}
#endif
PL_euid = suid;
# Now let's do the same for gid functions.
# TODO - Think about getgroups / setgroups, how do they best fit in?
# XXX - These need to be fixed for resuid/non-resuid systems.
void
drop_gid_temp(new_gid)
int new_gid;
CODE:
if (setresgid(-1,new_gid,getegid()) < 0) {
croak("Could not temporarily drop privs.");
}
if (getegid() != new_gid) {
croak("Dropping privs appears to have failed.");
}
PL_egid = new_gid;
void
drop_gid_perm(new_gid)
int new_gid;
PREINIT:
int rgid, egid, sgid;
CODE:
if (setresgid(new_gid,new_gid,new_gid) < 0) {
croak("Could not permanently drop privs.");
}
if (getresgid(&rgid, &egid, &sgid) < 0) {
croak("Could not check privileges were dropped.");
}
if (rgid != new_gid || egid != new_gid || sgid != new_gid) {
croak("Failed to drop privileges.");
}
PL_gid = new_gid;
PL_egid = new_gid;
void
restore_gid()
PREINIT:
int rgid, egid, sgid;
CODE:
if (getresgid(&rgid, &egid, &sgid) < 0) {
croak("Could not verify privileges.");
}
if (setresgid(-1,sgid,-1) < 0) {
croak("Could not set effective GID.");
}
if (getegid() != sgid) {
croak("Failed to set effective GID.");
}
PL_egid = sgid;