upstream commit

prevent authorized_keys options picked up on public key
 tests without a corresponding private key authentication being applied to
 other authentication methods. Reported by halex@, ok markus@

5 files changed, 20 insertions, 15 deletions

diff --git a/auth.h b/auth.h
index cc4086b3..8b27575b 100644
--- a/auth.h
+++ b/auth.h
@@ -126,7 +126,7 @@ int	 auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **);
 
 int	 auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *);
 int	 hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
-int	 user_key_allowed(struct passwd *, Key *);
+int	 user_key_allowed(struct passwd *, Key *, int);
 void	 pubkey_auth_info(Authctxt *, const Key *, const char *, ...)
 	    __attribute__((__format__ (printf, 3, 4)));
 void	 auth2_record_userkey(Authctxt *, struct sshkey *);
diff --git a/auth2-pubkey.c b/auth2-pubkey.c
index e103b70a..f96e843c 100644
--- a/auth2-pubkey.c
+++ b/auth2-pubkey.c
@@ -169,7 +169,7 @@ userauth_pubkey(Authctxt *authctxt)
 
 		/* test for correct signature */
 		authenticated = 0;
-		if (PRIVSEP(user_key_allowed(authctxt->pw, key)) &&
+		if (PRIVSEP(user_key_allowed(authctxt->pw, key, 1)) &&
 		    PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
 		    buffer_len(&b))) == 1) {
 			authenticated = 1;
@@ -191,7 +191,7 @@ userauth_pubkey(Authctxt *authctxt)
 		 * if a user is not allowed to login. is this an
 		 * issue? -markus
 		 */
-		if (PRIVSEP(user_key_allowed(authctxt->pw, key))) {
+		if (PRIVSEP(user_key_allowed(authctxt->pw, key, 0))) {
 			packet_start(SSH2_MSG_USERAUTH_PK_OK);
 			packet_put_string(pkalg, alen);
 			packet_put_string(pkblob, blen);
@@ -671,7 +671,7 @@ user_key_command_allowed2(struct passwd *user_pw, Key *key)
  * Check whether key authenticates and authorises the user.
  */
 int
-user_key_allowed(struct passwd *pw, Key *key)
+user_key_allowed(struct passwd *pw, Key *key, int auth_attempt)
 {
 	u_int success, i;
 	char *file;
diff --git a/monitor.c b/monitor.c
index d0ee4f7a..f520c978 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1185,7 +1185,7 @@ mm_answer_keyallowed(int sock, Buffer *m)
 	Key *key;
 	char *cuser, *chost;
 	u_char *blob;
-	u_int bloblen;
+	u_int bloblen, pubkey_auth_attempt;
 	enum mm_keytype type = 0;
 	int allowed = 0;
 
@@ -1195,6 +1195,7 @@ mm_answer_keyallowed(int sock, Buffer *m)
 	cuser = buffer_get_string(m, NULL);
 	chost = buffer_get_string(m, NULL);
 	blob = buffer_get_string(m, &bloblen);
+	pubkey_auth_attempt = buffer_get_int(m);
 
 	key = key_from_blob(blob, bloblen);
 
@@ -1220,7 +1221,8 @@ mm_answer_keyallowed(int sock, Buffer *m)
 			    pubkey_auth_attempt);
 			pubkey_auth_info(authctxt, key, NULL);
 			auth_method = "publickey";
-			if (options.pubkey_authentication && allowed != 1)
+			if (options.pubkey_authentication &&
+			    (!pubkey_auth_attempt || allowed != 1))
 				auth_clear_options();
 			break;
 		case MM_HOSTKEY:
diff --git a/monitor_wrap.c b/monitor_wrap.c
index d39d491c..e6217b3d 100644
--- a/monitor_wrap.c
+++ b/monitor_wrap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor_wrap.c,v 1.84 2015/02/16 22:13:32 djm Exp $ */
+/* $OpenBSD: monitor_wrap.c,v 1.85 2015/05/01 03:23:51 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -371,16 +371,17 @@ mm_auth_password(Authctxt *authctxt, char *password)
 }
 
 int
-mm_user_key_allowed(struct passwd *pw, Key *key)
+mm_user_key_allowed(struct passwd *pw, Key *key, int pubkey_auth_attempt)
 {
-	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
+	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
+	    pubkey_auth_attempt));
 }
 
 int
 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
     Key *key)
 {
-	return (mm_key_allowed(MM_HOSTKEY, user, host, key));
+	return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0));
 }
 
 int
@@ -390,13 +391,14 @@ mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
 	int ret;
 
 	key->type = KEY_RSA; /* XXX hack for key_to_blob */
-	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
+	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key, 0);
 	key->type = KEY_RSA1;
 	return (ret);
 }
 
 int
-mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
+mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key,
+    int pubkey_auth_attempt)
 {
 	Buffer m;
 	u_char *blob;
@@ -414,6 +416,7 @@ mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
 	buffer_put_cstring(&m, user ? user : "");
 	buffer_put_cstring(&m, host ? host : "");
 	buffer_put_string(&m, blob, len);
+	buffer_put_int(&m, pubkey_auth_attempt);
 	free(blob);
 
 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
diff --git a/monitor_wrap.h b/monitor_wrap.h
index e18784ac..de4a08f9 100644
--- a/monitor_wrap.h
+++ b/monitor_wrap.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor_wrap.h,v 1.26 2015/02/16 22:13:32 djm Exp $ */
+/* $OpenBSD: monitor_wrap.h,v 1.27 2015/05/01 03:23:51 djm Exp $ */
 
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
@@ -45,8 +45,8 @@ void mm_inform_authserv(char *, char *);
 struct passwd *mm_getpwnamallow(const char *);
 char *mm_auth2_read_banner(void);
 int mm_auth_password(struct Authctxt *, char *);
-int mm_key_allowed(enum mm_keytype, char *, char *, Key *);
-int mm_user_key_allowed(struct passwd *, Key *);
+int mm_key_allowed(enum mm_keytype, char *, char *, Key *, int);
+int mm_user_key_allowed(struct passwd *, Key *, int);
 int mm_hostbased_key_allowed(struct passwd *, char *, char *, Key *);
 int mm_auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *);
 int mm_key_verify(Key *, u_char *, u_int, u_char *, u_int);