X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/96f93d9e63db6fc5de5d6fabecb591c72942b38d..966c6ec04a47e5b2a417ce244be03869cdc6b71b:/usr/src/usr.bin/su/su.c

diff --git a/usr/src/usr.bin/su/su.c b/usr/src/usr.bin/su/su.c
index 6bb382b6f9..89e8a1d23f 100644
--- a/usr/src/usr.bin/su/su.c
+++ b/usr/src/usr.bin/su/su.c
@@ -1,177 +1,204 @@
+/*
+ * Copyright (c) 1988 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+char copyright[] =
+"@(#) Copyright (c) 1988 The Regents of the University of California.\n\
+ All rights reserved.\n";
+#endif /* not lint */
+
 #ifndef lint
-static char *sccsid = "@(#)su.c	4.9 (Berkeley) %G%";
-#endif
+static char sccsid[] = "@(#)su.c	5.10 (Berkeley) %G%";
+#endif /* not lint */
 
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <syslog.h>
 #include <stdio.h>
 #include <pwd.h>
 #include <grp.h>
-#include <sys/types.h>
-#include <sys/time.h>
-#include <sys/resource.h>
 
-char	userbuf[16]	= "USER=";
-char	homebuf[128]	= "HOME=";
-char	shellbuf[128]	= "SHELL=";
-char	pathbuf[128]	= "PATH=:/usr/ucb:/bin:/usr/bin";
-char	*cleanenv[] = { userbuf, homebuf, shellbuf, pathbuf, 0, 0 };
-char	*user = "root";
-char	*shell = "/bin/sh";
-int	fulllogin;
-int	fastlogin;
-
-extern char	**environ;
-struct	passwd *pwd;
-char	*crypt();
-char	*getpass();
-char	*getenv();
-
-main(argc,argv)
+main(argc, argv)
 	int argc;
-	char *argv[];
+	char **argv;
 {
-	char *password;
-	char buf[1000];
-	FILE *fp;
-
-again:
-	if (argc > 1 && strcmp(argv[1], "-f") == 0) {
-		fastlogin++;
-		argc--, argv++;
-		goto again;
-	}
-	if (argc > 1 && strcmp(argv[1], "-") == 0) {
-		fulllogin++;
-		argc--, argv++;
-		goto again;
-	}
-	if (argc > 1 && argv[1][0] != '-') {
-		user = argv[1];
-		argc--, argv++;
-	}
-	if ((pwd = getpwuid(getuid())) == NULL) {
-		fprintf(stderr, "Who are you?\n");
+	extern char **environ;
+	extern int errno, optind;
+	register struct passwd *pwd;
+	register char *p, **g;
+	struct group *gr;
+	uid_t ruid, getuid();
+	int asme, ch, fulllogin, fastlogin, prio;
+	enum { UNSET, YES, NO } iscsh = UNSET;
+	char *user, *shell, *username, *cleanenv[2], *nargv[4], **np;
+	char namebuf[50], shellbuf[MAXPATHLEN];
+	char *crypt(), *getpass(), *getenv(), *getlogin(), *rindex(), *strcpy();
+
+	np = &nargv[3];
+	*np-- = NULL;
+	asme = fulllogin = fastlogin = 0;
+	while ((ch = getopt(argc, argv, "-flm")) != EOF)
+		switch((char)ch) {
+		case 'f':
+			fastlogin = 1;
+			break;
+		case '-':
+		case 'l':
+			fulllogin = 1;
+			break;
+		case 'm':
+			asme = 1;
+			break;
+		case '?':
+		default:
+			fprintf(stderr, "usage: su [-flm] [login]\n");
+			exit(1);
+		}
+	argv += optind;
+
+	errno = 0;
+	prio = getpriority(PRIO_PROCESS, 0);
+	if (errno)
+		prio = 0;
+	(void)setpriority(PRIO_PROCESS, 0, -2);
+
+	/* get current login name and shell */
+	if ((pwd = getpwuid(ruid = getuid())) == NULL) {
+		fprintf(stderr, "su: who are you?\n");
 		exit(1);
 	}
-	strcpy(buf, pwd->pw_name);
+	username = strcpy(namebuf, pwd->pw_name);
+	if (asme)
+		if (pwd->pw_shell && *pwd->pw_shell)
+			shell = strcpy(shellbuf,  pwd->pw_shell);
+		else {
+			shell = "/bin/sh";
+			iscsh = NO;
+		}
+
+	/* get target login information */
+	user = *argv ? *argv : "root";
 	if ((pwd = getpwnam(user)) == NULL) {
-		fprintf(stderr, "Unknown login: %s\n", user);
+		fprintf(stderr, "su: unknown login %s\n", user);
 		exit(1);
 	}
-	/*
-	 * Only allow those in group zero to su to root.
-	 */
-	if (pwd->pw_uid == 0) {
-		struct	group *gr;
-		int i;
-
-		if ((gr = getgrgid(0)) != NULL) {
-			for (i = 0; gr->gr_mem[i] != NULL; i++)
-				if (strcmp(buf, gr->gr_mem[i]) == 0)
-					goto userok;
-			fprintf(stderr, "You do not have permission to su %s\n",
-				user);
-			exit(1);
-		}
-	userok:
-		setpriority(PRIO_PROCESS, 0, -2);
-	}
 
-	if (pwd->pw_passwd[0] == '\0' || getuid() == 0)
-		goto ok;
-	password = getpass("Password:");
-	if (strcmp(pwd->pw_passwd, crypt(password, pwd->pw_passwd)) != 0) {
-		fprintf(stderr, "Sorry\n");
-		if (pwd->pw_uid == 0) {
-			FILE *console = fopen("/dev/console", "w");
-			if (console != NULL) {
-				fprintf(console, "BADSU: %s %s\r\n",
-					getlogin(), ttyname(2));
-				fclose(console);
+	/* only allow those in group zero to su to root. */
+	if (pwd->pw_uid == 0 && (gr = getgrgid((gid_t)0)))
+		for (g = gr->gr_mem;; ++g) {
+			if (!*g) {
+				fprintf(stderr, "su: you are not in the correct group to su %s.\n", user);
+				exit(1);
 			}
+			if (!strcmp(username, *g))
+				break;
+		}
+
+	/* if target requires a password, verify it */
+	if (ruid && *pwd->pw_passwd) {
+		p = getpass("Password:");
+		if (strcmp(pwd->pw_passwd, crypt(p, pwd->pw_passwd))) {
+			fprintf(stderr, "Sorry\n");
+			if (pwd->pw_uid == 0)
+				syslog(LOG_CRIT|LOG_AUTH, "su: BAD SU %s on %s", username, ttyname(2));
+			exit(1);
 		}
-		exit(2);
 	}
-ok:
-	endpwent();
-	if (pwd->pw_uid == 0) {
-		FILE *console = fopen("/dev/console", "w");
-		if (console != NULL) {
-			fprintf(console, "SU: %s %s\r\n",
-				getlogin(), ttyname(2));
-			fclose(console);
+
+	/* if not asme or target's shell isn't standard, use it */
+	if (!asme || !chshell(pwd->pw_shell))
+		if (pwd->pw_shell && *pwd->pw_shell) {
+			shell = pwd->pw_shell;
+			iscsh = UNSET;
+		} else {
+			shell = "/bin/sh";
+			iscsh = NO;
 		}
+
+	/* if we're forking a csh, we want to slightly muck the args */
+	if (iscsh == UNSET) {
+		if (p = rindex(shell, '/'))
+			++p;
+		else
+			p = shell;
+		iscsh = strcmp(p, "csh") ? NO : YES;
 	}
+
+	/* set permissions */
 	if (setgid(pwd->pw_gid) < 0) {
 		perror("su: setgid");
-		exit(3);
+		exit(1);
 	}
 	if (initgroups(user, pwd->pw_gid)) {
 		fprintf(stderr, "su: initgroups failed\n");
-		exit(4);
+		exit(1);
 	}
 	if (setuid(pwd->pw_uid) < 0) {
 		perror("su: setuid");
-		exit(5);
-	}
-	if (pwd->pw_shell && *pwd->pw_shell)
-		shell = pwd->pw_shell;
-	if (fulllogin) {
-		cleanenv[4] = getenv("TERM");
-		environ = cleanenv;
+		exit(1);
 	}
-	if (strcmp(user, "root"))
-		setenv("USER", pwd->pw_name, userbuf);
-	setenv("SHELL", shell, shellbuf);
-	setenv("HOME", pwd->pw_dir, homebuf);
-	setpriority(PRIO_PROCESS, 0, 0);
-	if (fastlogin) {
-		*argv-- = "-f";
-		*argv = "su";
-	} else if (fulllogin) {
-		if (chdir(pwd->pw_dir) < 0) {
-			fprintf(stderr, "No directory\n");
-			exit(6);
-		}
-		*argv = "-su";
-	} else
-		*argv = "su";
-	execv(shell, argv);
-	fprintf(stderr, "No shell\n");
-	exit(7);
-}
 
-setenv(ename, eval, buf)
-	char *ename, *eval, *buf;
-{
-	register char *cp, *dp;
-	register char **ep = environ;
-
-	/*
-	 * this assumes an environment variable "ename" already exists
-	 */
-	while (dp = *ep++) {
-		for (cp = ename; *cp == *dp && *cp; cp++, dp++)
-			continue;
-		if (*cp == 0 && (*dp == '=' || *dp == 0)) {
-			strcat(buf, eval);
-			*--ep = buf;
-			return;
+	if (!asme) {
+		if (fulllogin) {
+			p = getenv("TERM");
+			cleanenv[0] = "PATH=:/usr/ucb:/bin:/usr/bin";
+			cleanenv[1] = NULL;
+			environ = cleanenv;
+			(void)setenv("TERM", p, 1);
+			if (chdir(pwd->pw_dir) < 0) {
+				fprintf(stderr, "su: no directory\n");
+				exit(1);
+			}
 		}
+		if (fulllogin || pwd->pw_uid)
+			(void)setenv("USER", pwd->pw_name, 1);
+		(void)setenv("HOME", pwd->pw_dir, 1);
+		(void)setenv("SHELL", shell, 1);
 	}
+
+	if (iscsh == YES) {
+		if (fastlogin)
+			*np-- = "-f";
+		if (asme)
+			*np-- = "-m";
+	}
+
+	/* csh strips the first character... */
+	*np = fulllogin ? "-su" : iscsh == YES ? "_su" : "su";
+
+	if (pwd->pw_uid == 0)
+		syslog(LOG_NOTICE|LOG_AUTH, "su: %s on %s",
+		    username, ttyname(2));
+
+	(void)setpriority(PRIO_PROCESS, 0, prio);
+
+	execv(shell, np);
+	fprintf(stderr, "su: no shell.\n");
+	exit(1);
 }
 
-char *
-getenv(ename)
-	char *ename;
+chshell(sh)
+	char *sh;
 {
-	register char *cp, *dp;
-	register char **ep = environ;
-
-	while (dp = *ep++) {
-		for (cp = ename; *cp == *dp && *cp; cp++, dp++)
-			continue;
-		if (*cp == 0 && (*dp == '=' || *dp == 0))
-			return (*--ep);
-	}
-	return ((char *)0);
+	char *cp, *getusershell();
+
+	while ((cp = getusershell()) != NULL)
+		if (!strcmp(cp, sh))
+			return(1);
+	return(0);
 }