Support processing of partial TLS record headers

diff --git a/src/libtls/tls.c b/src/libtls/tls.c
index 61787e366838d896e6058c6acc2272806e82f112..34de7cc4299612be53d67be1f8fd35d06e00d283 100644 (file)
--- a/src/libtls/tls.c
+++ b/src/libtls/tls.c
@@ -55,6 +55,15 @@ ENUM_NEXT(tls_handshake_type_names, TLS_FINISHED, TLS_FINISHED, TLS_CLIENT_KEY_E
        "Finished");
 ENUM_END(tls_handshake_type_names, TLS_FINISHED);
 
+/**
+ * TLS record
+ */
+typedef struct __attribute__((packed)) {
+       u_int8_t type;
+       u_int16_t version;
+       u_int16_t length;
+       char data[];
+} tls_record_t;
 
 typedef struct private_tls_t private_tls_t;
 
@@ -147,17 +156,17 @@ struct private_tls_t {
         * Number of bytes processed from output buffer
         */
        size_t outpos;
-};
 
-/**
- * TLS record
- */
-typedef struct __attribute__((packed)) {
-       u_int8_t type;
-       u_int16_t version;
-       u_int16_t length;
-       char data[];
-} tls_record_t;
+       /**
+        * Partial TLS record header received
+        */
+       tls_record_t head;
+
+       /**
+        * Position in partially received record header
+        */
+       size_t headpos;
+};
 
 METHOD(tls_t, process, status_t,
        private_tls_t *this, void *buf, size_t buflen)
@@ -166,12 +175,32 @@ METHOD(tls_t, process, status_t,
        status_t status;
        u_int len;
 
+       if (this->headpos)
+       {       /* have a partial TLS record header, try to complete it */
+               len = min(buflen, sizeof(this->head) - this->headpos);
+               memcpy(((char*)&this->head) + this->headpos, buf, len);
+               this->headpos += len;
+               buflen -= len;
+               buf += len;
+               if (this->headpos == sizeof(this->head))
+               {       /* header complete, allocate space with new header */
+                       len = untoh16(&this->head.length);
+                       this->input = chunk_alloc(len + sizeof(tls_record_t));
+                       memcpy(this->input.ptr, &this->head, sizeof(this->head));
+                       this->inpos = sizeof(this->head);
+                       this->headpos = 0;
+               }
+       }
+
        while (buflen)
        {
                if (this->input.len == 0)
                {
                        if (buflen < sizeof(tls_record_t))
                        {
+                               DBG2(DBG_TLS, "received incomplete TLS record header");
+                               memcpy(&this->head, buf, buflen);
+                               this->headpos = buflen;
                                break;
                        }
                        while (TRUE)
@@ -226,11 +255,6 @@ METHOD(tls_t, process, status_t,
                        }
                }
        }
-       if (buflen != 0)
-       {
-               DBG1(DBG_TLS, "received incomplete TLS record header");
-               return FAILED;
-       }
        return NEED_MORE;
 }