Flatten and clean up.

1 files changed, 188 insertions, 0 deletions

diff --git a/bin/su/su.c b/bin/su/su.c
new file mode 100644
index 0000000..4c7d0eb
--- /dev/null
+++ b/bin/su/su.c
@@ -0,0 +1,188 @@
+/*-
+ * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
+ * Copyright (c) 2004-2007 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * This software was developed for the FreeBSD Project by ThinkSec AS and
+ * Network Associates Laboratories, the Security Research Division of
+ * Network Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
+ * ("CBOSS"), as part of the DARPA CHATS research program.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id: su.c 408 2007-12-21 11:36:24Z des $
+ */
+
+#include <sys/param.h>
+#include <sys/wait.h>
+
+#include <err.h>
+#include <grp.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+#include <unistd.h>
+
+#include <security/pam_appl.h>
+#include <security/openpam.h>	/* for openpam_ttyconv() */
+
+extern char **environ;
+
+static pam_handle_t *pamh;
+static struct pam_conv pamc;
+
+static void
+usage(void)
+{
+
+	fprintf(stderr, "Usage: su [login [args]]\n");
+	exit(1);
+}
+
+int
+main(int argc, char *argv[])
+{
+	char hostname[MAXHOSTNAMELEN];
+	const char *user, *tty;
+	const void *item;
+	char **args, **pam_envlist, **pam_env;
+	struct passwd *pwd;
+	int o, pam_err, status;
+	pid_t pid;
+
+	while ((o = getopt(argc, argv, "h")) != -1)
+		switch (o) {
+		case 'h':
+		default:
+			usage();
+		}
+
+	argc -= optind;
+	argv += optind;
+
+	if (argc > 0) {
+		user = *argv;
+		--argc;
+		++argv;
+	} else {
+		user = "root";
+	}
+
+	/* initialize PAM */
+	pamc.conv = &openpam_ttyconv;
+	pam_start("su", user, &pamc, &pamh);
+
+	/* set some items */
+	gethostname(hostname, sizeof(hostname));
+	if ((pam_err = pam_set_item(pamh, PAM_RHOST, hostname)) != PAM_SUCCESS)
+		goto pamerr;
+	user = getlogin();
+	if ((pam_err = pam_set_item(pamh, PAM_RUSER, user)) != PAM_SUCCESS)
+		goto pamerr;
+	tty = ttyname(STDERR_FILENO);
+	if ((pam_err = pam_set_item(pamh, PAM_TTY, tty)) != PAM_SUCCESS)
+		goto pamerr;
+
+	/* authenticate the applicant */
+	if ((pam_err = pam_authenticate(pamh, 0)) != PAM_SUCCESS)
+		goto pamerr;
+	if ((pam_err = pam_acct_mgmt(pamh, 0)) == PAM_NEW_AUTHTOK_REQD)
+		pam_err = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
+	if (pam_err != PAM_SUCCESS)
+		goto pamerr;
+
+	/* establish the requested credentials */
+	if ((pam_err = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS)
+		goto pamerr;
+
+	/* authentication succeeded; open a session */
+	if ((pam_err = pam_open_session(pamh, 0)) != PAM_SUCCESS)
+		goto pamerr;
+
+	/* get mapped user name; PAM may have changed it */
+	pam_err = pam_get_item(pamh, PAM_USER, &item);
+	if (pam_err != PAM_SUCCESS || (pwd = getpwnam(user = item)) == NULL)
+		goto pamerr;
+
+	/* export PAM environment */
+	if ((pam_envlist = pam_getenvlist(pamh)) != NULL) {
+		for (pam_env = pam_envlist; *pam_env != NULL; ++pam_env) {
+			putenv(*pam_env);
+			free(*pam_env);
+		}
+		free(pam_envlist);
+	}
+
+	/* build argument list */
+	if ((args = calloc(argc + 2, sizeof *args)) == NULL) {
+		warn("calloc()");
+		goto err;
+	}
+	*args = pwd->pw_shell;
+	memcpy(args + 1, argv, argc * sizeof *args);
+
+	/* fork and exec */
+	switch ((pid = fork())) {
+	case -1:
+		warn("fork()");
+		goto err;
+	case 0:
+		/* child: give up privs and start a shell */
+
+		/* set uid and groups */
+		if (initgroups(pwd->pw_name, pwd->pw_gid) == -1) {
+			warn("initgroups()");
+			_exit(1);
+		}
+		if (setgid(pwd->pw_gid) == -1) {
+			warn("setgid()");
+			_exit(1);
+		}
+		if (setuid(pwd->pw_uid) == -1) {
+			warn("setuid()");
+			_exit(1);
+		}
+		execve(*args, args, environ);
+		warn("execve()");
+		_exit(1);
+	default:
+		/* parent: wait for child to exit */
+		waitpid(pid, &status, 0);
+
+		/* close the session and release PAM resources */
+		pam_err = pam_close_session(pamh, 0);
+		pam_end(pamh, pam_err);
+
+		exit(WEXITSTATUS(status));
+	}
+
+pamerr:
+	fprintf(stderr, "Sorry\n");
+err:
+	pam_end(pamh, pam_err);
+	exit(1);
+}