Support CONTINUATION frame reception

lib/includes/nghttp2/nghttp2.h

@@ -364,7 +364,11 @@ typedef enum {
   /**
    * The WINDOW_UPDATE frame.
    */
-  NGHTTP2_WINDOW_UPDATE = 9
+  NGHTTP2_WINDOW_UPDATE = 9,
+  /**
+   * The CONTINUATION frame.
+   */
+  NGHTTP2_CONTINUATION = 10
 } nghttp2_frame_type;
 
 /**

lib/nghttp2_frame.c

@@ -250,10 +250,6 @@ int nghttp2_frame_unpack_headers_payload(nghttp2_headers *frame,
                                          const uint8_t *payload,
                                          size_t payloadlen)
 {
-  /* TODO Return error if header continuation is used for now */
-  if((frame->hd.flags & NGHTTP2_FLAG_END_HEADERS) == 0) {
-    return NGHTTP2_ERR_PROTO;
-  }
   if(frame->hd.flags & NGHTTP2_FLAG_PRIORITY) {
     assert(payloadlen == 4);
     frame->pri = nghttp2_get_uint32(payload) & NGHTTP2_PRIORITY_MASK;
@@ -409,10 +405,6 @@ int nghttp2_frame_unpack_push_promise_payload(nghttp2_push_promise *frame,
                                               const uint8_t *payload,
                                               size_t payloadlen)
 {
-  /* TODO Return error if header continuation is used for now */
-  if((frame->hd.flags & NGHTTP2_FLAG_END_PUSH_PROMISE) == 0) {
-    return NGHTTP2_ERR_PROTO;
-  }
   frame->promised_stream_id = nghttp2_get_uint32(payload) &
     NGHTTP2_STREAM_ID_MASK;
   frame->nva = NULL;

lib/nghttp2_session.c

@@ -3398,6 +3398,7 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
   size_t readlen;
   int rv;
   int busy = 0;
+  nghttp2_frame_hd cont_hd;
 
   for(;;) {
     switch(iframe->state) {
@@ -3408,6 +3409,7 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
       if(iframe->left) {
         return in - first;
       }
+
       nghttp2_frame_unpack_frame_hd(&iframe->frame.hd, iframe->buf);
       iframe->payloadleft = iframe->frame.hd.length;
       iframe->buflen = 0;
@@ -3505,6 +3507,15 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
         iframe->state = NGHTTP2_IB_READ_NBYTE;
         iframe->left = 8;
         break;
+      case NGHTTP2_CONTINUATION:
+        rv = nghttp2_session_terminate_session(session,
+                                               NGHTTP2_PROTOCOL_ERROR);
+        if(nghttp2_is_fatal(rv)) {
+          return rv;
+        }
+        busy = 1;
+        iframe->state = NGHTTP2_IB_IGN_PAYLOAD;
+        break;
       default:
         busy = 1;
         iframe->state = NGHTTP2_IB_IGN_PAYLOAD;
@@ -3592,6 +3603,8 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
                      readlen, iframe->payloadleft));
       rv = inflate_header_block(session, &iframe->frame, &readlen,
                                 (uint8_t*)in, readlen,
+                                (iframe->frame.hd.flags &
+                                 NGHTTP2_FLAG_END_HEADERS) &&
                                 iframe->payloadleft == readlen,
                                 iframe->state == NGHTTP2_IB_READ_HEADER_BLOCK);
       if(nghttp2_is_fatal(rv)) {
@@ -3620,7 +3633,18 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
           return rv;
         }
       }
-      nghttp2_inbound_frame_reset(session);
+      if((iframe->frame.hd.flags & NGHTTP2_FLAG_END_HEADERS) == 0) {
+        iframe->left = NGHTTP2_FRAME_HEAD_LENGTH;
+        iframe->error_code = 0;
+        iframe->buflen = 0;
+        if(iframe->state == NGHTTP2_IB_READ_HEADER_BLOCK) {
+          iframe->state = NGHTTP2_IB_EXPECT_CONTINUATION;
+        } else {
+          iframe->state = NGHTTP2_IB_IGN_CONTINUATION;
+        }
+      } else {
+        nghttp2_inbound_frame_reset(session);
+      }
       break;
     case NGHTTP2_IB_IGN_PAYLOAD:
       readlen = inbound_frame_payload_readlen(iframe, in, last);
@@ -3688,6 +3712,52 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session,
       }
       nghttp2_inbound_frame_reset(session);
       break;
+    case NGHTTP2_IB_EXPECT_CONTINUATION:
+    case NGHTTP2_IB_IGN_CONTINUATION:
+#ifdef DEBUGBUILD
+      if(iframe->state == NGHTTP2_IB_EXPECT_CONTINUATION) {
+        fprintf(stderr, "[IB_EXPECT_CONTINUATION]\n");
+      } else {
+        fprintf(stderr, "[IB_IGN_CONTINUATION]\n");
+      }
+#endif /* DEBUGBUILD */
+      readlen = inbound_frame_buf_read(iframe, in, last);
+      in += readlen;
+      if(iframe->left) {
+        return in - first;
+      }
+      nghttp2_frame_unpack_frame_hd(&cont_hd, iframe->buf);
+      iframe->payloadleft = cont_hd.length;
+      if(cont_hd.type != NGHTTP2_CONTINUATION ||
+         cont_hd.stream_id != iframe->frame.hd.stream_id) {
+        rv = nghttp2_session_terminate_session(session,
+                                               NGHTTP2_PROTOCOL_ERROR);
+        if(nghttp2_is_fatal(rv)) {
+          return rv;
+        }
+
+        rv = session_call_on_end_headers(session, &iframe->frame,
+                                         NGHTTP2_PROTOCOL_ERROR);
+
+        if(nghttp2_is_fatal(rv)) {
+          return rv;
+        }
+        /* Mark inflater bad so that we won't perform further decoding */
+        session->hd_inflater.ctx.bad = 1;
+        busy = 1;
+        iframe->state = NGHTTP2_IB_IGN_PAYLOAD;
+        break;
+      }
+      if(cont_hd.flags & NGHTTP2_FLAG_END_HEADERS) {
+        iframe->frame.hd.flags |= NGHTTP2_FLAG_END_HEADERS;
+      }
+      busy = 1;
+      if(iframe->state == NGHTTP2_IB_EXPECT_CONTINUATION) {
+        iframe->state = NGHTTP2_IB_READ_HEADER_BLOCK;
+      } else {
+        iframe->state = NGHTTP2_IB_IGN_HEADER_BLOCK;
+      }
+      break;
     case NGHTTP2_IB_READ_DATA:
       DEBUGF(fprintf(stderr, "[IB_READ_DATA]\n"));
       readlen = inbound_frame_payload_readlen(iframe, in, last);

lib/nghttp2_session.h

@@ -81,6 +81,8 @@ typedef enum {
   NGHTTP2_IB_FRAME_SIZE_ERROR,
   NGHTTP2_IB_READ_SETTINGS,
   NGHTTP2_IB_READ_GOAWAY_DEBUG,
+  NGHTTP2_IB_EXPECT_CONTINUATION,
+  NGHTTP2_IB_IGN_CONTINUATION,
   NGHTTP2_IB_READ_DATA,
   NGHTTP2_IB_IGN_DATA
 } nghttp2_inbound_state;

tests/main.c

@@ -83,6 +83,8 @@ int main(int argc, char* argv[])
                    test_nghttp2_session_recv_eof) ||
       !CU_add_test(pSuite, "session_recv_data",
                    test_nghttp2_session_recv_data) ||
+      !CU_add_test(pSuite, "session_recv_continuation",
+                   test_nghttp2_session_recv_continuation) ||
       !CU_add_test(pSuite, "session_continue", test_nghttp2_session_continue) ||
       !CU_add_test(pSuite, "session_add_frame",
                    test_nghttp2_session_add_frame) ||

tests/nghttp2_session_test.c

@@ -660,6 +660,122 @@ void test_nghttp2_session_recv_data(void)
   nghttp2_session_del(session);
 }
 
+void test_nghttp2_session_recv_continuation(void)
+{
+  nghttp2_session *session;
+  nghttp2_session_callbacks callbacks;
+  const nghttp2_nv nv1[] = {
+    MAKE_NV("method", "GET"),
+    MAKE_NV("path", "/")
+  };
+  nghttp2_nv *nva;
+  size_t nvlen;
+  nghttp2_frame frame;
+  uint8_t *framedata = NULL;
+  size_t framedatacap = 0;
+  size_t framedatalen;
+  size_t framedataoff;
+  ssize_t rv;
+  my_user_data ud;
+  nghttp2_hd_deflater deflater;
+  uint8_t data[1024];
+  size_t datalen;
+  nghttp2_frame_hd cont_hd;
+
+  memset(&callbacks, 0, sizeof(nghttp2_session_callbacks));
+  callbacks.on_header_callback = on_header_callback;
+  callbacks.on_end_headers_callback = on_end_headers_callback;
+
+  nghttp2_session_server_new(&session, &callbacks, &ud);
+
+  nghttp2_hd_deflate_init(&deflater, NGHTTP2_HD_SIDE_REQUEST);
+
+  /* Make 1 HEADERS and insert CONTINUATION header */
+  nvlen = nghttp2_nv_array_copy(&nva, nv1, ARRLEN(nv1));
+  nghttp2_frame_headers_init(&frame.headers, NGHTTP2_FLAG_NONE,
+                             1, NGHTTP2_PRI_DEFAULT, nva, nvlen);
+  framedatalen = nghttp2_frame_pack_headers(&framedata, &framedatacap,
+                                            &frame.headers,
+                                            &deflater);
+  nghttp2_frame_headers_free(&frame.headers);
+
+  memcpy(data, framedata, 9);
+  datalen = 9;
+  framedataoff = NGHTTP2_FRAME_HEAD_LENGTH + 1;
+
+  nghttp2_put_uint16be(data, 1);
+
+  /* First CONTINUATION, 2 bytes */
+  cont_hd.length = 2;
+  cont_hd.type = NGHTTP2_CONTINUATION;
+  cont_hd.flags = NGHTTP2_FLAG_NONE;
+  cont_hd.stream_id = 1;
+
+  nghttp2_frame_pack_frame_hd(data + datalen, &cont_hd);
+  datalen += NGHTTP2_FRAME_HEAD_LENGTH;
+
+  memcpy(data + datalen, framedata + framedataoff, cont_hd.length);
+  datalen += cont_hd.length;
+  framedataoff += cont_hd.length;
+
+  /* Second CONTINUATION, rest of the bytes */
+  cont_hd.length = framedatalen - framedataoff;
+  cont_hd.flags = NGHTTP2_FLAG_END_HEADERS;
+  cont_hd.stream_id = 1;
+
+  nghttp2_frame_pack_frame_hd(data + datalen, &cont_hd);
+  datalen += NGHTTP2_FRAME_HEAD_LENGTH;
+
+  memcpy(data + datalen, framedata + framedataoff, cont_hd.length);
+  datalen += cont_hd.length;
+  framedataoff += cont_hd.length;
+
+  assert(framedataoff == framedatalen);
+
+  ud.header_cb_called = 0;
+  rv = nghttp2_session_mem_recv(session, data, datalen);
+  CU_ASSERT(rv == datalen);
+  CU_ASSERT(2 == ud.header_cb_called);
+
+  nghttp2_hd_deflate_free(&deflater);
+  nghttp2_session_del(session);
+
+  /* Expecting CONTINUATION, but get the other frame */
+  nghttp2_session_server_new(&session, &callbacks, &ud);
+
+  nghttp2_hd_deflate_init(&deflater, NGHTTP2_HD_SIDE_REQUEST);
+
+  /* HEADERS without END_HEADERS flag */
+  nvlen = nghttp2_nv_array_copy(&nva, nv1, ARRLEN(nv1));
+  nghttp2_frame_headers_init(&frame.headers, NGHTTP2_FLAG_NONE,
+                             1, NGHTTP2_PRI_DEFAULT, nva, nvlen);
+  framedatalen = nghttp2_frame_pack_headers(&framedata, &framedatacap,
+                                            &frame.headers,
+                                            &deflater);
+  nghttp2_frame_headers_free(&frame.headers);
+  memcpy(data, framedata, framedatalen);
+  datalen = framedatalen;
+
+  /* Followed by PRIORITY */
+  nghttp2_frame_priority_init(&frame.priority, 1, 0);
+  framedatalen = nghttp2_frame_pack_priority(&framedata, &framedatacap,
+                                             &frame.priority);
+  memcpy(data + datalen, framedata, framedatalen);
+  datalen += framedatalen;
+
+  ud.end_headers_cb_called = 0;
+  rv = nghttp2_session_mem_recv(session, data, datalen);
+  CU_ASSERT(datalen == rv);
+
+  CU_ASSERT(1 == ud.end_headers_cb_called);
+  CU_ASSERT(NGHTTP2_GOAWAY ==
+            OB_CTRL_TYPE(nghttp2_session_get_next_ob_item(session)));
+
+  free(framedata);
+  nghttp2_hd_deflate_free(&deflater);
+  nghttp2_session_del(session);
+}
+
 void test_nghttp2_session_continue(void)
 {
   nghttp2_session *session;

tests/nghttp2_session_test.h

@@ -30,6 +30,7 @@ void test_nghttp2_session_recv_invalid_stream_id(void);
 void test_nghttp2_session_recv_invalid_frame(void);
 void test_nghttp2_session_recv_eof(void);
 void test_nghttp2_session_recv_data(void);
+void test_nghttp2_session_recv_continuation(void);
 void test_nghttp2_session_continue(void);
 void test_nghttp2_session_add_frame(void);
 void test_nghttp2_session_on_request_headers_received(void);