support supplementary group in {Allow,Deny}Groups

from stevesk@pobox.com

5 files changed, 34 insertions, 42 deletions

diff --git a/usr.bin/ssh/auth.c b/usr.bin/ssh/auth.c
index 182d6464922..957b93db4c1 100644
--- a/usr.bin/ssh/auth.c
+++ b/usr.bin/ssh/auth.c
@@ -33,7 +33,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: auth.c,v 1.11 2000/10/11 20:27:23 markus Exp $");
+RCSID("$OpenBSD: auth.c,v 1.12 2001/01/13 18:56:48 markus Exp $");
 
 #include "xmalloc.h"
 #include "rsa.h"
@@ -46,6 +46,7 @@ RCSID("$OpenBSD: auth.c,v 1.11 2000/10/11 20:27:23 markus Exp $");
 #include "compat.h"
 #include "channels.h"
 #include "match.h"
+#include "groupaccess.h"
 
 #include "bufaux.h"
 #include "ssh2.h"
@@ -56,11 +57,11 @@ RCSID("$OpenBSD: auth.c,v 1.11 2000/10/11 20:27:23 markus Exp $");
 extern ServerOptions options;
 
 /*
- * Check if the user is allowed to log in via ssh. If user is listed in
- * DenyUsers or user's primary group is listed in DenyGroups, false will
- * be returned. If AllowUsers isn't empty and user isn't listed there, or
- * if AllowGroups isn't empty and user isn't listed there, false will be
- * returned.
+ * Check if the user is allowed to log in via ssh. If user is listed
+ * in DenyUsers or one of user's groups is listed in DenyGroups, false
+ * will be returned. If AllowUsers isn't empty and user isn't listed
+ * there, or if AllowGroups isn't empty and one of user's groups isn't
+ * listed there, false will be returned.
  * If the user's shell is not executable, false will be returned.
  * Otherwise true is returned.
  */
@@ -68,12 +69,11 @@ int
 allowed_user(struct passwd * pw)
 {
 	struct stat st;
-	struct group *grp;
 	char *shell;
 	int i;
 
 	/* Shouldn't be called if pw is NULL, but better safe than sorry... */
-	if (!pw)
+	if (!pw || !pw->pw_name)
 		return 0;
 
 	/*
@@ -90,16 +90,12 @@ allowed_user(struct passwd * pw)
 
 	/* Return false if user is listed in DenyUsers */
 	if (options.num_deny_users > 0) {
-		if (!pw->pw_name)
-			return 0;
 		for (i = 0; i < options.num_deny_users; i++)
 			if (match_pattern(pw->pw_name, options.deny_users[i]))
 				return 0;
 	}
 	/* Return false if AllowUsers isn't empty and user isn't listed there */
 	if (options.num_allow_users > 0) {
-		if (!pw->pw_name)
-			return 0;
 		for (i = 0; i < options.num_allow_users; i++)
 			if (match_pattern(pw->pw_name, options.allow_users[i]))
 				break;
@@ -107,35 +103,29 @@ allowed_user(struct passwd * pw)
 		if (i >= options.num_allow_users)
 			return 0;
 	}
-	/* Get the primary group name if we need it. Return false if it fails */
 	if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
-		grp = getgrgid(pw->pw_gid);
-		if (!grp)
+		/* Get the user's group access list (primary and supplementary) */
+		if (ga_init(pw->pw_name, pw->pw_gid) == 0)
 			return 0;
 
-		/* Return false if user's group is listed in DenyGroups */
-		if (options.num_deny_groups > 0) {
-			if (!grp->gr_name)
+		/* Return false if one of user's groups is listed in DenyGroups */
+		if (options.num_deny_groups > 0)
+			if (ga_match(options.deny_groups,
+			    options.num_deny_groups)) {
+				ga_free();
 				return 0;
-			for (i = 0; i < options.num_deny_groups; i++)
-				if (match_pattern(grp->gr_name, options.deny_groups[i]))
-					return 0;
-		}
+			}
 		/*
-		 * Return false if AllowGroups isn't empty and user's group
+		 * Return false if AllowGroups isn't empty and one of user's groups
 		 * isn't listed there
 		 */
-		if (options.num_allow_groups > 0) {
-			if (!grp->gr_name)
-				return 0;
-			for (i = 0; i < options.num_allow_groups; i++)
-				if (match_pattern(grp->gr_name, options.allow_groups[i]))
-					break;
-			/* i < options.num_allow_groups iff we break for
-			   loop */
-			if (i >= options.num_allow_groups)
+		if (options.num_allow_groups > 0)
+			if (!ga_match(options.allow_groups,
+			    options.num_allow_groups)) {
+				ga_free();
 				return 0;
-		}
+			}
+		ga_free();
 	}
 	/* We found no reason not to let this user try to log on... */
 	return 1;
diff --git a/usr.bin/ssh/auth2.c b/usr.bin/ssh/auth2.c
index 3edde42f850..8ac9aa0868b 100644
--- a/usr.bin/ssh/auth2.c
+++ b/usr.bin/ssh/auth2.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: auth2.c,v 1.26 2001/01/13 18:21:48 markus Exp $");
+RCSID("$OpenBSD: auth2.c,v 1.27 2001/01/13 18:56:48 markus Exp $");
 
 #include <openssl/dsa.h>
 #include <openssl/rsa.h>
@@ -298,7 +298,7 @@ userauth_log(Authctxt *authctxt, int authenticated, char *method)
 	if (authctxt->valid) {
 		user = authctxt->pw->pw_uid == 0 ? "ROOT" : authctxt->user;
 	} else {
-		user = "NOUSER";
+		user = authctxt->user ? authctxt->user : "NOUSER";
 	}
 
 	authlog("%s %s for %.200s from %.200s port %d ssh2",
diff --git a/usr.bin/ssh/sshd.8 b/usr.bin/ssh/sshd.8
index fef26b50bc6..a513978d950 100644
--- a/usr.bin/ssh/sshd.8
+++ b/usr.bin/ssh/sshd.8
@@ -34,7 +34,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.\" $OpenBSD: sshd.8,v 1.80 2001/01/08 22:29:05 markus Exp $
+.\" $OpenBSD: sshd.8,v 1.81 2001/01/13 18:56:48 markus Exp $
 .Dd September 25, 1999
 .Dt SSHD 8
 .Os
@@ -303,14 +303,14 @@ Default is
 This keyword can be followed by a number of group names, separated
 by spaces.
 If specified, login is allowed only for users whose primary
-group matches one of the patterns.
+group or supplementary group list matches one of the patterns.
 .Ql \&*
 and
 .Ql ?
 can be used as
 wildcards in the patterns.
 Only group names are valid; a numerical group ID isn't recognized.
-By default login is allowed regardless of the primary group.
+By default login is allowed regardless of the group list.
 .Pp
 .It Cm AllowTcpForwarding
 Specifies whether TCP forwarding is permitted.
@@ -354,15 +354,15 @@ The default is
 .It Cm DenyGroups
 This keyword can be followed by a number of group names, separated
 by spaces.
-Users whose primary group matches one of the patterns
-aren't allowed to log in.
+Users whose primary group or supplementary group list matches
+one of the patterns aren't allowed to log in.
 .Ql \&*
 and
 .Ql ?
 can be used as
 wildcards in the patterns.
 Only group names are valid; a numerical group ID isn't recognized.
-By default login is allowed regardless of the primary group.
+By default login is allowed regardless of the group list.
 .Pp
 .It Cm DenyUsers
 This keyword can be followed by a number of user names, separated
diff --git a/usr.bin/ssh/sshd/Makefile b/usr.bin/ssh/sshd/Makefile
index 0a9fba8e052..6e4b3fe8637 100644
--- a/usr.bin/ssh/sshd/Makefile
+++ b/usr.bin/ssh/sshd/Makefile
@@ -9,7 +9,8 @@ CFLAGS+=-DHAVE_LOGIN_CAP
 
 SRCS=	sshd.c auth-rhosts.c auth-passwd.c auth-rsa.c auth-rh-rsa.c \
 	pty.c log-server.c login.c servconf.c serverloop.c \
-	auth.c auth1.c auth2.c auth-options.c session.c dh.c
+	auth.c auth1.c auth2.c auth-options.c session.c dh.c \
+	groupaccess.c
 
 .include <bsd.own.mk> # for KERBEROS and AFS
 
diff --git a/usr.bin/ssh/sshd_config b/usr.bin/ssh/sshd_config
index ad8db2746cf..fb5dc7b2b48 100644
--- a/usr.bin/ssh/sshd_config
+++ b/usr.bin/ssh/sshd_config
@@ -57,3 +57,4 @@ PermitEmptyPasswords no
 #Subsystem	sftp	/usr/libexec/sftp-server
 #MaxStartups 10:30:60
 #Banner /etc/issue.net
+DenyGroups nossh