session: add getters for session cipher names

Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

include/libssh/libssh.h

@@ -642,6 +642,8 @@ LIBSSH_API int ssh_event_remove_session(ssh_event event, ssh_session session);
 LIBSSH_API void ssh_event_free(ssh_event event);
 LIBSSH_API const char* ssh_get_clientbanner(ssh_session session);
 LIBSSH_API const char* ssh_get_serverbanner(ssh_session session);
+LIBSSH_API const char* ssh_get_cipher_in(ssh_session session);
+LIBSSH_API const char* ssh_get_cipher_out(ssh_session session);
 
 #ifndef LIBSSH_LEGACY_0_4
 #include "libssh/legacy.h"

src/session.c

@@ -309,6 +309,38 @@ const char* ssh_get_serverbanner(ssh_session session) {
 	return session->serverbanner;
 }
 
+/**
+ * @brief get the name of the input for the given session.
+ *
+ * @param[in] session The SSH session.
+ *
+ * @return Returns cipher name or NULL.
+ */
+const char* ssh_get_cipher_in(ssh_session session) {
+    if ((session != NULL) &&
+        (session->current_crypto != NULL) &&
+        (session->current_crypto->in_cipher != NULL)) {
+        return session->current_crypto->in_cipher->name;
+    }
+    return NULL;
+}
+
+/**
+ * @brief get the name of the output cipher for the given session.
+ *
+ * @param[in] session The SSH session.
+ *
+ * @return Returns cipher name or NULL.
+ */
+const char* ssh_get_cipher_out(ssh_session session) {
+    if ((session != NULL) &&
+        (session->current_crypto != NULL) &&
+        (session->current_crypto->out_cipher != NULL)) {
+        return session->current_crypto->out_cipher->name;
+    }
+    return NULL;
+}
+
 /**
  * @brief Disconnect impolitely from a remote host by closing the socket.
  *