diff options
Diffstat (limited to 'usr/src/cmd/ssh/libssh/common/uidswap.c')
-rw-r--r-- | usr/src/cmd/ssh/libssh/common/uidswap.c | 257 |
1 files changed, 0 insertions, 257 deletions
diff --git a/usr/src/cmd/ssh/libssh/common/uidswap.c b/usr/src/cmd/ssh/libssh/common/uidswap.c deleted file mode 100644 index 942b22a749..0000000000 --- a/usr/src/cmd/ssh/libssh/common/uidswap.c +++ /dev/null @@ -1,257 +0,0 @@ -/* - * Author: Tatu Ylonen <ylo@cs.hut.fi> - * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland - * All rights reserved - * Code for uid-swapping. - * - * As far as I am concerned, the code I have written for this software - * can be used freely for any purpose. Any derived versions of this - * software must be clearly marked as such, and if the derived work is - * incompatible with the protocol description in the RFC file, it must be - * called by a name other than "ssh" or "Secure Shell". - */ -/* - * Copyright 2009 Sun Microsystems, Inc. All rights reserved. - * Use is subject to license terms. - */ - -#include "includes.h" -RCSID("$OpenBSD: uidswap.c,v 1.23 2002/07/15 17:15:31 stevesk Exp $"); - -#include <priv.h> - -#include "log.h" -#include "uidswap.h" -#include "buffer.h" -#include "servconf.h" - -/* - * Note: all these functions must work in all of the following cases: - * 1. euid=0, ruid=0 - * 2. euid=0, ruid!=0 - * 3. euid!=0, ruid!=0 - * Additionally, they must work regardless of whether the system has - * POSIX saved uids or not. - */ - -#if defined(_POSIX_SAVED_IDS) && !defined(BROKEN_SAVED_UIDS) -/* Lets assume that posix saved ids also work with seteuid, even though that - is not part of the posix specification. */ -#define SAVED_IDS_WORK -/* Saved effective uid. */ -static uid_t saved_euid = 0; -static gid_t saved_egid = 0; -#endif - -/* Saved effective uid. */ -static int privileged = 0; -static int temporarily_use_uid_effective = 0; -static int ngroups_max = -1; -static gid_t *saved_egroups, *user_groups; -static int saved_egroupslen = -1, user_groupslen = -1; - -/* - * Temporarily changes to the given uid. If the effective user - * id is not root, this does nothing. This call cannot be nested. - */ -void -temporarily_use_uid(struct passwd *pw) -{ - /* Save the current euid, and egroups. */ -#ifdef SAVED_IDS_WORK - saved_euid = geteuid(); - saved_egid = getegid(); - debug("temporarily_use_uid: %u/%u (e=%u/%u)", - (u_int)pw->pw_uid, (u_int)pw->pw_gid, - (u_int)saved_euid, (u_int)saved_egid); - if (saved_euid != 0) { - privileged = 0; - return; - } -#else - if (geteuid() != 0) { - privileged = 0; - return; - } -#endif /* SAVED_IDS_WORK */ - - privileged = 1; - temporarily_use_uid_effective = 1; - - if (ngroups_max < 0) { - ngroups_max = sysconf(_SC_NGROUPS_MAX); - saved_egroups = malloc(ngroups_max * sizeof (gid_t)); - user_groups = malloc(ngroups_max * sizeof (gid_t)); - if (saved_egroups == NULL || user_groups == NULL) - fatal("malloc(gid array): %.100s", strerror(errno)); - } - - saved_egroupslen = getgroups(ngroups_max, saved_egroups); - if (saved_egroupslen < 0) - fatal("getgroups: %.100s", strerror(errno)); - - /* set and save the user's groups */ - if (user_groupslen == -1) { - if (initgroups(pw->pw_name, pw->pw_gid) < 0) - fatal("initgroups: %s: %.100s", pw->pw_name, - strerror(errno)); - user_groupslen = getgroups(ngroups_max, user_groups); - if (user_groupslen < 0) - fatal("getgroups: %.100s", strerror(errno)); - } - /* Set the effective uid to the given (unprivileged) uid. */ - if (setgroups(user_groupslen, user_groups) < 0) - fatal("setgroups: %.100s", strerror(errno)); -#ifdef SAVED_IDS_WORK - /* Set saved gid and set real gid */ - if (setregid(pw->pw_gid, -1) == -1) - debug("setregid(%u, -1): %.100s", (uint_t)pw->pw_gid, strerror(errno)); - /* Set saved uid and set real uid */ - if (setreuid(pw->pw_uid, -1) == -1) - debug("setreuid(%u, -1): %.100s", (uint_t)pw->pw_uid, strerror(errno)); -#else - /* Propagate the privileged gid to all of our gids. */ - if (setgid(getegid()) < 0) - debug("setgid %u: %.100s", (u_int) getegid(), strerror(errno)); - /* Propagate the privileged uid to all of our uids. */ - if (setuid(geteuid()) < 0) - debug("setuid %u: %.100s", (u_int) geteuid(), strerror(errno)); -#endif /* SAVED_IDS_WORK */ - /* Set effective gid */ - if (setegid(pw->pw_gid) == -1) - fatal("setegid %u: %.100s", (u_int)pw->pw_uid, - strerror(errno)); - /* Set effective uid */ - if (seteuid(pw->pw_uid) == -1) - fatal("seteuid %u: %.100s", (u_int)pw->pw_uid, - strerror(errno)); - /* - * If saved set ids work then - * - * ruid == euid == pw->pw_uid - * saved uid = previous euid - * rgid == egid == pw->pw_gid - * saved gid = previous egid - */ -} - -/* - * Restores to the original (privileged) uid. - */ -void -restore_uid(void) -{ - /* it's a no-op unless privileged */ - if (!privileged) { - debug("restore_uid: (unprivileged)"); - return; - } - if (!temporarily_use_uid_effective) - fatal("restore_uid: temporarily_use_uid not effective"); - -#ifdef SAVED_IDS_WORK - debug("restore_uid: %u/%u", (u_int)saved_euid, (u_int)saved_egid); - /* Set the effective uid back to the saved privileged uid. */ - if (seteuid(saved_euid) < 0) - fatal("seteuid %u: %.100s", (u_int)saved_euid, strerror(errno)); - if (setuid(saved_euid) < 0) - fatal("setuid %u: %.100s", (u_int)saved_euid, strerror(errno)); - if (setegid(saved_egid) < 0) - fatal("setegid %u: %.100s", (u_int)saved_egid, strerror(errno)); - if (setgid(saved_egid) < 0) - fatal("setgid %u: %.100s", (u_int)saved_egid, strerror(errno)); -#else /* SAVED_IDS_WORK */ - /* - * We are unable to restore the real uid to its unprivileged value. - * Propagate the real uid (usually more privileged) to effective uid - * as well. - */ - setuid(getuid()); - setgid(getgid()); -#endif /* SAVED_IDS_WORK */ - - if (setgroups(saved_egroupslen, saved_egroups) < 0) - fatal("setgroups: %.100s", strerror(errno)); - temporarily_use_uid_effective = 0; -} - -/* - * Permanently sets all uids to the given uid. This cannot be called while - * temporarily_use_uid is effective. Note that when the ChrootDirectory option - * is in use we keep a few privileges so that we can call chroot(2) later while - * already running under UIDs of a connecting user. - */ -void -permanently_set_uid(struct passwd *pw, char *chroot_directory) -{ - priv_set_t *pset; - - if (temporarily_use_uid_effective) - fatal("%s: temporarily_use_uid effective", __func__); - - debug("%s: %u/%u", __func__, (u_int)pw->pw_uid, (u_int)pw->pw_gid); - - if (initgroups(pw->pw_name, pw->pw_gid) < 0) - fatal("initgroups: %s: %.100s", pw->pw_name, - strerror(errno)); - - if (setgid(pw->pw_gid) < 0) - fatal("setgid %u: %.100s", (u_int)pw->pw_gid, strerror(errno)); - - /* - * If root is connecting we are done now. Note that we must have called - * setgid() in case that the SSH server was run under a group other than - * root. - */ - if (pw->pw_uid == 0) - return; - - /* - * This means we will keep all privileges after the UID change. - */ - if (setpflags(PRIV_AWARE, 1) != 0) - fatal("setpflags: %s", strerror(errno)); - - /* Now we are running under UID of the user. */ - if (setuid(pw->pw_uid) < 0) - fatal("setuid %u: %.100s", (u_int)pw->pw_uid, strerror(errno)); - - /* - * We will run with the privileges from the Inheritable set as - * we would have after exec(2) if we had stayed in NPA mode - * before setuid(2) call (see privileges(5), user_attr(4), and - * pam_unix_cred(5)). We want to run with P = E = I, with I as - * set by pam_unix_cred(5). We also add PRIV_PROC_CHROOT, - * obviously, and then PRIV_PROC_FORK and PRIV_PROC_EXEC, since - * those two might have been removed from the I set. Note that - * we are expected to finish the login process without them in - * the I set, the important thing is that those not be passed on - * to a shell or a subsystem later if they were not set in - * pam_unix_cred(5). - */ - if ((pset = priv_allocset()) == NULL) - fatal("priv_allocset: %s", strerror(errno)); - if (getppriv(PRIV_INHERITABLE, pset) != 0) - fatal("getppriv: %s", strerror(errno)); - - /* We do not need PRIV_PROC_CHROOT unless chroot()ing. */ - if (chroot_requested(chroot_directory) && - priv_addset(pset, PRIV_PROC_CHROOT) == -1) { - fatal("%s: priv_addset failed", __func__); - } - - if (priv_addset(pset, PRIV_PROC_FORK) == -1 || - priv_addset(pset, PRIV_PROC_EXEC) == -1) { - fatal("%s: priv_addset failed", __func__); - } - - /* Set only P; this will also set E. */ - if (setppriv(PRIV_SET, PRIV_PERMITTED, pset) == -1) - fatal("setppriv: %s", strerror(errno)); - - /* We don't need the PA flag anymore. */ - if (setpflags(PRIV_AWARE, 0) == -1) - fatal("setpflags: %s", strerror(errno)); - - priv_freeset(pset); -} |