[PATCH net-next 14/23] rxrpc: Support keys with multiple authentication tokens

[David Howells]

rxrpc-type keys can have multiple tokens attached for different security
classes.  Currently, rxrpc always picks the first one, whether or not the
security class it indicates is supported.

Add preliminary support for choosing which security class will be used
(this will need to be directed from a higher layer) and go through the
tokens to find one that's supported.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

 net/rxrpc/ar-internal.h |    4 +++-
 net/rxrpc/conn_event.c  |    3 ++-
 net/rxrpc/insecure.c    |    3 ++-
 net/rxrpc/rxkad.c       |    5 ++---
 net/rxrpc/security.c    |   15 ++++++++-------
 5 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index a3b3901bc7f7..c8f821c17d5b 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -12,6 +12,7 @@
 #include <net/netns/generic.h>
 #include <net/sock.h>
 #include <net/af_rxrpc.h>
+#include <keys/rxrpc-type.h>
 #include "protocol.h"
 
 #if 0
@@ -217,7 +218,8 @@ struct rxrpc_security {
 	void (*exit)(void);
 
 	/* initialise a connection's security */
-	int (*init_connection_security)(struct rxrpc_connection *);
+	int (*init_connection_security)(struct rxrpc_connection *,
+					struct rxrpc_key_token *);
 
 
 	/* impose security on a packet */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index abe761c66f67..75139a3d015a 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -333,7 +333,8 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
 		if (ret < 0)
 			return ret;
 
-		ret = conn->security->init_connection_security(conn);
+		ret = conn->security->init_connection_security(
+			conn, conn->params.key->payload.data[0]);
 		if (ret < 0)
 			return ret;
 
diff --git a/net/rxrpc/insecure.c b/net/rxrpc/insecure.c
index a9c3959810ea..914e2f2e2990 100644
--- a/net/rxrpc/insecure.c
+++ b/net/rxrpc/insecure.c
@@ -8,7 +8,8 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
-static int none_init_connection_security(struct rxrpc_connection *conn)
+static int none_init_connection_security(struct rxrpc_connection *conn,
+					 struct rxrpc_key_token *token)
 {
 	return 0;
 }
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 5e10e0f9d7b7..4ca9ca95d2bf 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -52,15 +52,14 @@ static DEFINE_MUTEX(rxkad_ci_mutex);
 /*
  * initialise connection security
  */
-static int rxkad_init_connection_security(struct rxrpc_connection *conn)
+static int rxkad_init_connection_security(struct rxrpc_connection *conn,
+					  struct rxrpc_key_token *token)
 {
 	struct crypto_sync_skcipher *ci;
-	struct rxrpc_key_token *token;
 	int ret;
 
 	_enter("{%d},{%x}", conn->debug_id, key_serial(conn->params.key));
 
-	token = conn->params.key->payload.data[0];
 	conn->security_ix = token->security_index;
 
 	ci = crypto_alloc_sync_skcipher("pcbc(fcrypt)", 0, 0);
diff --git a/net/rxrpc/security.c b/net/rxrpc/security.c
index 9b1fb9ed0717..0c5168f52bd6 100644
--- a/net/rxrpc/security.c
+++ b/net/rxrpc/security.c
@@ -81,16 +81,17 @@ int rxrpc_init_client_conn_security(struct rxrpc_connection *conn)
 	if (ret < 0)
 		return ret;
 
-	token = key->payload.data[0];
-	if (!token)
-		return -EKEYREJECTED;
+	for (token = key->payload.data[0]; token; token = token->next) {
+		sec = rxrpc_security_lookup(token->security_index);
+		if (sec)
+			goto found;
+	}
+	return -EKEYREJECTED;
 
-	sec = rxrpc_security_lookup(token->security_index);
-	if (!sec)
-		return -EKEYREJECTED;
+found:
 	conn->security = sec;
 
-	ret = conn->security->init_connection_security(conn);
+	ret = conn->security->init_connection_security(conn, token);
 	if (ret < 0) {
 		conn->security = &rxrpc_no_security;
 		return ret;