Make use_yp() smarter about figuring out whether a user is local or

NIS (or both, or neither). Also add support for -l and -y flags to
force behavior to local or NIS. use_yp() also goes out of its way to
retrieve the correct password database information (local or NIS)
depending on what the situation since getpwent() & co. can't
necessarily be trusted in some cases.

Also document new flags in man page.

usr.bin/chpass/chpass.1

@@ -56,7 +56,7 @@ The information is formatted and supplied to an editor for changes.
 Only the information that the user is allowed to change is displayed.
 .Pp
 The options are as follows:
-.Bl -tag -width Ds
+.Bl -tag -width flag
 .It Fl a
 The super-user is allowed to directly supply a user database
 entry, in the format specified by
@@ -271,6 +271,27 @@ otherwise
 .Xr yppasswdd 8
 will refuse to update the NIS maps.
 .El
+.Pp
+There are also two extra option flags that are available when
+.Nm chpass
+is compiles with NIS support:
+.Bl -tag -width flag
+.It Fl l
+The
+.Fl l
+flag forces
+.Nm chpass
+to modify the local copy of a user's password
+information in the even that a user exists in both
+the local and NIS databases.
+.It Fl y
+This flag has the opposite effect of
+.Fl l .
+This flag is largely redundant since
+.Nm chpass
+operates on NIS entries by default if NIS is enabled.
+.El
+.Pp
 .Sh FILES
 .Bl -tag -width /etc/master.passwd -compact
 .It Pa /etc/master.passwd

usr.bin/chpass/chpass.c

@@ -40,7 +40,7 @@ static char copyright[] =
 #ifndef lint
 static char sccsid[] = "From: @(#)chpass.c	8.4 (Berkeley) 4/2/94";
 static char rcsid[] =
-	"$Id: chpass.c,v 1.3 1995/05/30 06:29:36 rgrimes Exp $";
+	"$Id: chpass.c,v 1.4 1995/08/13 16:12:24 wpaul Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -85,9 +85,17 @@ main(argc, argv)
 	struct passwd *pw, lpw;
 	int ch, pfd, tfd;
 	char *arg;
+#ifdef YP
+	int force_local = 0;
+	int force_yp = 0;
+#endif
 
 	op = EDITENTRY;
+#ifdef YP
+	while ((ch = getopt(argc, argv, "a:p:s:ly")) != EOF)
+#else
 	while ((ch = getopt(argc, argv, "a:p:s:")) != EOF)
+#endif
 		switch(ch) {
 		case 'a':
 			op = LOADENTRY;
@@ -101,6 +109,14 @@ main(argc, argv)
 			op = NEWPW;
 			arg = optarg;
 			break;
+#ifdef YP
+		case 'l':
+			force_local = 1;
+			break;
+		case 'y':
+			force_yp = 1;
+			break;
+#endif
 		case '?':
 		default:
 			usage();
@@ -152,20 +168,29 @@ main(argc, argv)
 	}
 
 #ifdef YP
-	/*
-	 * XXX The man page says the data returned by getpwent()
-	 * and friends is stored in static buffers that may be
-	 * overwritten after successive invokations. Unfortunately,
-	 * we need to call getpwent() more than once with NIS
-	 * enabled.
-	 */
 	pw->pw_name = strdup(pw->pw_name);
-	pw->pw_passwd = strdup(pw->pw_passwd);
-	pw->pw_class = strdup(pw->pw_class);
-	pw->pw_gecos = strdup(pw->pw_gecos);
-	pw->pw_shell = strdup(pw->pw_shell);
-	pw->pw_dir = strdup(pw->pw_dir);
 	_use_yp = use_yp(pw->pw_name);
+	if (_use_yp == USER_YP_ONLY) {
+		if (!force_local) {
+			_use_yp = 1;
+			pw = (struct passwd *)&yp_password;
+		} else
+			errx(1, "unknown local user: %s.", pw->pw_name);
+	} else if (_use_yp == USER_LOCAL_ONLY) {
+		if (!force_yp) {
+			_use_yp = 0;
+			pw = (struct passwd *)&local_password;
+		} else
+			errx(1, "unknown NIS user: %s.", pw->pw_name);
+	} else if (_use_yp == USER_YP_AND_LOCAL) {
+		if (!force_local) {
+			_use_yp = 1;
+			pw = (struct passwd *)&yp_password;
+		} else {
+			_use_yp = 0;
+			pw = (struct passwd *)&local_password;
+		}
+	}
 #endif /* YP */
 
 	/*
@@ -231,6 +256,10 @@ usage()
 {
 
 	(void)fprintf(stderr,
+#ifdef YP
+		"usage: chpass [-l] [-y] [-a list] [-p encpass] [-s shell] [user]\n");
+#else
 		"usage: chpass [-a list] [-p encpass] [-s shell] [user]\n");
+#endif
 	exit(1);
 }

usr.bin/chpass/pw_yp.c

@@ -35,7 +35,7 @@
  * Center for Telecommunications Research
  * Columbia University, New York City
  *
- *	$Id$
+ *	$Id: pw_yp.c,v 1.1 1995/08/13 16:12:27 wpaul Exp $
  */
 
 #ifdef YP
@@ -75,42 +75,157 @@ HASHINFO openinfo = {
 
 int _use_yp = 0;
 
+/* Save the local and NIS password information */
+struct passwd local_password;
+struct passwd yp_password;
+
+
+void copy_yp_pass(p, x, m)
+char *p;
+int x, m;
+{
+	register char *t, *s = p;
+
+	yp_password.pw_fields = 0;
+
+	t = (char *)malloc(m + 10);
+
+	/* Turn all colons into NULLs */
+	while (strchr(s, ':')) {
+		s = (strchr(s, ':') + 1);
+		*(s - 1)= '\0';
+	}
+
+#define EXPAND(e)       e = t; while (*t++ = *p++);
+        EXPAND(yp_password.pw_name);
+	yp_password.pw_fields |= _PWF_NAME;
+        EXPAND(yp_password.pw_passwd);
+	yp_password.pw_fields |= _PWF_PASSWD;
+	yp_password.pw_uid = atoi(p);
+        p += (strlen(p) + 1);
+	yp_password.pw_fields |= _PWF_UID;
+	yp_password.pw_gid = atoi(p);
+        p += (strlen(p) + 1);
+	yp_password.pw_fields |= _PWF_GID;
+	if (x) {
+		EXPAND(yp_password.pw_class);
+		yp_password.pw_fields |= _PWF_CLASS;
+		yp_password.pw_change = atol(p);
+		p += (strlen(p) + 1);
+		yp_password.pw_fields |= _PWF_CHANGE;
+		yp_password.pw_expire = atol(p);
+		p += (strlen(p) + 1);
+		yp_password.pw_expire |= _PWF_EXPIRE;
+	}
+        EXPAND(yp_password.pw_gecos);
+	yp_password.pw_fields |= _PWF_GECOS;
+        EXPAND(yp_password.pw_dir);
+	yp_password.pw_fields |= _PWF_DIR;
+        EXPAND(yp_password.pw_shell);
+	yp_password.pw_fields |= _PWF_SHELL;
+
+	return;
+}
+
+void copy_local_pass(p,m)
+char *p;
+int m;
+{
+	register char *t;
+
+	t = (char *)malloc(m + 10);
+
+        EXPAND(local_password.pw_name);
+        EXPAND(local_password.pw_passwd);
+        bcopy(p, (char *)&local_password.pw_uid, sizeof(int));
+        p += sizeof(int);
+        bcopy(p, (char *)&local_password.pw_gid, sizeof(int));
+        p += sizeof(int);
+       	bcopy(p, (char *)&local_password.pw_change, sizeof(time_t));
+       	p += sizeof(time_t);
+       	EXPAND(local_password.pw_class);
+        EXPAND(local_password.pw_gecos);
+        EXPAND(local_password.pw_dir);
+        EXPAND(local_password.pw_shell);
+        bcopy(p, (char *)&local_password.pw_expire, sizeof(time_t));
+        p += sizeof(time_t);
+        bcopy(p, (char *)&local_password.pw_fields, sizeof local_password.pw_fields);
+        p += sizeof local_password.pw_fields;
+
+	return;
+}
+
 /*
  * Check if the user we're working with is local or in NIS.
  */
 int use_yp (user)
 char *user;
 {
-	int yp_enabled = 0, user_not_local = 0, exists = 0;
+	int user_local = 0, user_yp = 0, user_exists = 0;
 	DB *dbp;
 	DBT key,data;
 	char bf[UT_NAMESIZE + 2];
+	char *domain;
+	char *result;
+	int resultlen, rval;
 
-	if ((dbp = dbopen(_PATH_MP_DB, O_RDONLY, PERM_SECURE,
+
+	/* Is the user anywhere */
+	if (getpwnam(user) != NULL)
+		user_exists = 1;
+
+	if ((dbp = dbopen(_PATH_SMP_DB, O_RDONLY, PERM_SECURE,
 			DB_HASH, &openinfo)) == NULL)
 			errx(1, "error opening database: %s.", _PATH_MP_DB);
+
+	/* Is NIS turned on */
 	bf[0] = _PW_KEYYPENABLED;
 	key.data = (u_char *)bf;
 	key.size = 1;
-	if (!(dbp->get)(dbp,&key,&data,0))
-		yp_enabled = 1;
+	if (!(dbp->get)(dbp,&key,&data,0)) {
+		if ((rval = yp_get_default_domain(&domain))) {
+			warnx("can't get local NIS domain name: %s",yperr_string(rval));
+			pw_error(NULL, 0, 1);
+		}
+
+		/* Is the user in the NIS passwd map */
+		if (!yp_match(domain, "passwd.byname", user, strlen(user),
+		    &result, &resultlen)) {
+			user_yp = 1;
+			copy_yp_pass(result, 0, resultlen);
+			free(result);
+		}
+		/* Is the user in the NIS passwd map */
+		if (user_yp && !yp_match(domain, "master.passwd.byname",	
+		    user, strlen(user),
+		    &result, &resultlen)) {
+			copy_yp_pass(result, 1, resultlen);
+		}
+		free(result);
+	}
+
+	/* Is the user in the local password database */
 
 	bf[0] = _PW_KEYBYNAME;
 	bcopy((char *)user, bf + 1, MIN(strlen(user), UT_NAMESIZE));
 	key.data = (u_char *)bf;
 	key.size = strlen(user) + 1;
-	if ((dbp->get)(dbp,&key,&data,0))
-		user_not_local = 1;
-	
+	if (!(dbp->get)(dbp,&key,&data,0)) {
+		user_local = 1;
+		copy_local_pass(data.data, data.size);
+	}
+
 	(dbp->close)(dbp);
 
-	if (getpwnam(user) != NULL)
-		exists = 1;
-
-	if (yp_enabled && user_not_local && exists)
-		return(1);
-	else
-		return(0);
+	if (user_local && user_yp && user_exists)
+		return(USER_YP_AND_LOCAL);
+	else if (!user_local && user_yp && user_exists)
+		return(USER_YP_ONLY);
+	else if (user_local && !user_yp && user_exists)
+		return(USER_LOCAL_ONLY);
+	else if (!user_exists)
+		return(USER_UNKNOWN);
+	return(-1);
 }
 
 /*

usr.bin/chpass/pw_yp.h

@@ -35,11 +35,18 @@
  * Center for Telecommunications Research
  * Columbia University, New York City
  *
- *	$Id$
+ *	$Id: pw_yp.h,v 1.1 1995/08/13 16:12:28 wpaul Exp $
  */
 
 #ifdef YP
+/* Four possible return codes from use_yp() */
+#define USER_UNKNOWN 0
+#define USER_YP_ONLY 1
+#define USER_LOCAL_ONLY 2
+#define USER_YP_AND_LOCAL 3
 extern	int		_use_yp;
+extern	struct passwd	local_password;
+extern	struct passwd	yp_password;
 void	yp_submit	__P(( struct passwd * ));
 int	use_yp		__P(( char * ));
 #endif /* YP */