grpc_error *grpc_chttp2_window_update_parser_parse(
grpc_exec_ctx *exec_ctx, void *parser, grpc_chttp2_transport *t,
grpc_chttp2_stream *s, grpc_slice slice, int is_last) {
uint8_t *const beg = GRPC_SLICE_START_PTR(slice);
uint8_t *const end = GRPC_SLICE_END_PTR(slice);
uint8_t *cur = beg;
grpc_chttp2_window_update_parser *p = parser;
while (p->byte != 4 && cur != end) {
p->amount |= ((uint32_t)*cur) << (8 * (3 - p->byte));
cur++;
p->byte++;
}
if (s != NULL) {
s->stats.incoming.framing_bytes += (uint32_t)(end - cur);
}
if (p->byte == 4) {
uint32_t received_update = p->amount;
if (received_update == 0 || (received_update & 0x80000000u)) {
char *msg;
gpr_asprintf(&msg, "invalid window update bytes: %d", p->amount);
grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
gpr_free(msg);
return err;
}
GPR_ASSERT(is_last);
if (t->incoming_stream_id != 0) {
if (s != NULL) {
GRPC_CHTTP2_FLOW_CREDIT_STREAM("parse", t, s, outgoing_window_delta,
received_update);
if (grpc_chttp2_list_remove_stalled_by_stream(t, s)) {
grpc_chttp2_become_writable(
exec_ctx, t, s, GRPC_CHTTP2_STREAM_WRITE_INITIATE_UNCOVERED,
"stream.read_flow_control");
}
}
} else {
bool was_zero = t->outgoing_window <= 0;
GRPC_CHTTP2_FLOW_CREDIT_TRANSPORT("parse", t, outgoing_window,
received_update);
bool is_zero = t->outgoing_window <= 0;
if (was_zero && !is_zero) {
grpc_chttp2_initiate_write(exec_ctx, t, "new_global_flow_control");
}
}
}
return GRPC_ERROR_NONE;
}
int grpc_chttp2_unlocking_check_writes(
grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_global *transport_global,
grpc_chttp2_transport_writing *transport_writing) {
grpc_chttp2_stream_global *stream_global;
grpc_chttp2_stream_writing *stream_writing;
GPR_TIMER_BEGIN("grpc_chttp2_unlocking_check_writes", 0);
/* simple writes are queued to qbuf, and flushed here */
gpr_slice_buffer_swap(&transport_global->qbuf, &transport_writing->outbuf);
GPR_ASSERT(transport_global->qbuf.count == 0);
grpc_chttp2_hpack_compressor_set_max_table_size(
&transport_writing->hpack_compressor,
transport_global->settings[GRPC_PEER_SETTINGS]
[GRPC_CHTTP2_SETTINGS_HEADER_TABLE_SIZE]);
if (transport_global->dirtied_local_settings &&
!transport_global->sent_local_settings) {
gpr_slice_buffer_add(
&transport_writing->outbuf,
grpc_chttp2_settings_create(
transport_global->settings[GRPC_SENT_SETTINGS],
transport_global->settings[GRPC_LOCAL_SETTINGS],
transport_global->force_send_settings, GRPC_CHTTP2_NUM_SETTINGS));
transport_global->force_send_settings = 0;
transport_global->dirtied_local_settings = 0;
transport_global->sent_local_settings = 1;
}
GRPC_CHTTP2_FLOW_MOVE_TRANSPORT("write", transport_writing, outgoing_window,
transport_global, outgoing_window);
if (transport_writing->outgoing_window > 0) {
while (grpc_chttp2_list_pop_stalled_by_transport(transport_global,
&stream_global)) {
grpc_chttp2_become_writable(exec_ctx, transport_global, stream_global,
false, "transport.read_flow_control");
}
}
/* for each grpc_chttp2_stream that's become writable, frame it's data
(according to available window sizes) and add to the output buffer */
while (grpc_chttp2_list_pop_writable_stream(
transport_global, transport_writing, &stream_global, &stream_writing)) {
bool sent_initial_metadata = stream_writing->sent_initial_metadata;
bool become_writable = false;
stream_writing->id = stream_global->id;
stream_writing->read_closed = stream_global->read_closed;
GRPC_CHTTP2_FLOW_MOVE_STREAM("write", transport_writing, stream_writing,
outgoing_window, stream_global,
outgoing_window);
if (!sent_initial_metadata && stream_global->send_initial_metadata) {
stream_writing->send_initial_metadata =
stream_global->send_initial_metadata;
stream_global->send_initial_metadata = NULL;
become_writable = true;
sent_initial_metadata = true;
}
if (sent_initial_metadata) {
if (stream_global->send_message != NULL) {
gpr_slice hdr = gpr_slice_malloc(5);
uint8_t *p = GPR_SLICE_START_PTR(hdr);
uint32_t len = stream_global->send_message->length;
GPR_ASSERT(stream_writing->send_message == NULL);
p[0] = (stream_global->send_message->flags &
GRPC_WRITE_INTERNAL_COMPRESS) != 0;
p[1] = (uint8_t)(len >> 24);
p[2] = (uint8_t)(len >> 16);
p[3] = (uint8_t)(len >> 8);
p[4] = (uint8_t)(len);
gpr_slice_buffer_add(&stream_writing->flow_controlled_buffer, hdr);
if (stream_global->send_message->length > 0) {
stream_writing->send_message = stream_global->send_message;
} else {
stream_writing->send_message = NULL;
}
stream_writing->stream_fetched = 0;
stream_global->send_message = NULL;
}
if ((stream_writing->send_message != NULL ||
stream_writing->flow_controlled_buffer.length > 0) &&
stream_writing->outgoing_window > 0) {
if (transport_writing->outgoing_window > 0) {
become_writable = true;
} else {
grpc_chttp2_list_add_stalled_by_transport(transport_writing,
stream_writing);
}
}
if (stream_global->send_trailing_metadata) {
stream_writing->send_trailing_metadata =
stream_global->send_trailing_metadata;
stream_global->send_trailing_metadata = NULL;
become_writable = true;
}
}
if (!stream_global->read_closed &&
stream_global->unannounced_incoming_window_for_writing > 1024) {
GRPC_CHTTP2_FLOW_MOVE_STREAM("write", transport_global, stream_writing,
announce_window, stream_global,
unannounced_incoming_window_for_writing);
become_writable = true;
}
if (become_writable) {
grpc_chttp2_list_add_writing_stream(transport_writing, stream_writing);
} else {
GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2_writing");
}
}
void grpc_chttp2_publish_reads(
grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_global *transport_global,
grpc_chttp2_transport_parsing *transport_parsing) {
grpc_chttp2_stream_global *stream_global;
grpc_chttp2_stream_parsing *stream_parsing;
int was_zero;
int is_zero;
/* transport_parsing->last_incoming_stream_id is used as
last-grpc_chttp2_stream-id when
sending GOAWAY frame.
https://tools.ietf.org/html/draft-ietf-httpbis-http2-17#section-6.8
says that last-grpc_chttp2_stream-id is peer-initiated grpc_chttp2_stream
ID. So,
since we don't have server pushed streams, client should send
GOAWAY last-grpc_chttp2_stream-id=0 in this case. */
if (!transport_parsing->is_client) {
transport_global->last_incoming_stream_id =
transport_parsing->last_incoming_stream_id;
}
/* update global settings */
if (transport_parsing->settings_updated) {
memcpy(transport_global->settings[GRPC_PEER_SETTINGS],
transport_parsing->settings, sizeof(transport_parsing->settings));
transport_parsing->settings_updated = 0;
}
/* update settings based on ack if received */
if (transport_parsing->settings_ack_received) {
memcpy(transport_global->settings[GRPC_ACKED_SETTINGS],
transport_global->settings[GRPC_SENT_SETTINGS],
GRPC_CHTTP2_NUM_SETTINGS * sizeof(uint32_t));
transport_parsing->settings_ack_received = 0;
transport_global->sent_local_settings = 0;
}
/* move goaway to the global state if we received one (it will be
published later */
if (transport_parsing->goaway_received) {
grpc_chttp2_add_incoming_goaway(exec_ctx, transport_global,
(uint32_t)transport_parsing->goaway_error,
transport_parsing->goaway_text);
transport_parsing->goaway_text = gpr_empty_slice();
transport_parsing->goaway_received = 0;
}
/* propagate flow control tokens to global state */
was_zero = transport_global->outgoing_window <= 0;
GRPC_CHTTP2_FLOW_MOVE_TRANSPORT("parsed", transport_global, outgoing_window,
transport_parsing, outgoing_window);
is_zero = transport_global->outgoing_window <= 0;
if (was_zero && !is_zero) {
while (grpc_chttp2_list_pop_stalled_by_transport(transport_global,
&stream_global)) {
grpc_chttp2_become_writable(transport_global, stream_global);
}
}
if (transport_parsing->incoming_window <
transport_global->connection_window_target * 3 / 4) {
int64_t announce_bytes = transport_global->connection_window_target -
transport_parsing->incoming_window;
GRPC_CHTTP2_FLOW_CREDIT_TRANSPORT("parsed", transport_global,
announce_incoming_window, announce_bytes);
GRPC_CHTTP2_FLOW_CREDIT_TRANSPORT("parsed", transport_parsing,
incoming_window, announce_bytes);
}
/* for each stream that saw an update, fixup global state */
while (grpc_chttp2_list_pop_parsing_seen_stream(
transport_global, transport_parsing, &stream_global, &stream_parsing)) {
if (stream_parsing->seen_error) {
stream_global->seen_error = true;
stream_global->exceeded_metadata_size =
stream_parsing->exceeded_metadata_size;
grpc_chttp2_list_add_check_read_ops(transport_global, stream_global);
}
/* flush stats to global stream state */
grpc_transport_move_stats(&stream_parsing->stats, &stream_global->stats);
/* update outgoing flow control window */
was_zero = stream_global->outgoing_window <= 0;
GRPC_CHTTP2_FLOW_MOVE_STREAM("parsed", transport_global, stream_global,
outgoing_window, stream_parsing,
outgoing_window);
is_zero = stream_global->outgoing_window <= 0;
if (was_zero && !is_zero) {
grpc_chttp2_become_writable(transport_global, stream_global);
}
stream_global->max_recv_bytes -= (uint32_t)GPR_MIN(
stream_global->max_recv_bytes, stream_parsing->received_bytes);
stream_parsing->received_bytes = 0;
/* publish incoming stream ops */
if (stream_global->incoming_frames.tail != NULL) {
stream_global->incoming_frames.tail->is_tail = 0;
}
if (stream_parsing->data_parser.incoming_frames.head != NULL) {
grpc_chttp2_list_add_check_read_ops(transport_global, stream_global);
}
grpc_chttp2_incoming_frame_queue_merge(
&stream_global->incoming_frames,
&stream_parsing->data_parser.incoming_frames);
if (stream_global->incoming_frames.tail != NULL) {
stream_global->incoming_frames.tail->is_tail = 1;
}
if (!stream_global->published_initial_metadata &&
stream_parsing->got_metadata_on_parse[0]) {
stream_parsing->got_metadata_on_parse[0] = 0;
stream_global->published_initial_metadata = 1;
GPR_SWAP(grpc_chttp2_incoming_metadata_buffer,
stream_parsing->metadata_buffer[0],
stream_global->received_initial_metadata);
grpc_chttp2_list_add_check_read_ops(transport_global, stream_global);
}
if (!stream_global->published_trailing_metadata &&
stream_parsing->got_metadata_on_parse[1]) {
stream_parsing->got_metadata_on_parse[1] = 0;
stream_global->published_trailing_metadata = 1;
GPR_SWAP(grpc_chttp2_incoming_metadata_buffer,
stream_parsing->metadata_buffer[1],
stream_global->received_trailing_metadata);
grpc_chttp2_list_add_check_read_ops(transport_global, stream_global);
}
if (stream_parsing->forced_close_error != GRPC_ERROR_NONE) {
intptr_t reason;
bool has_reason = grpc_error_get_int(stream_parsing->forced_close_error,
GRPC_ERROR_INT_HTTP2_ERROR, &reason);
if (has_reason && reason != GRPC_CHTTP2_NO_ERROR) {
grpc_status_code status_code =
has_reason
? grpc_chttp2_http2_error_to_grpc_status(
(grpc_chttp2_error_code)reason, stream_global->deadline)
: GRPC_STATUS_INTERNAL;
const char *status_details =
grpc_error_string(stream_parsing->forced_close_error);
gpr_slice slice_details = gpr_slice_from_copied_string(status_details);
grpc_error_free_string(status_details);
grpc_chttp2_fake_status(exec_ctx, transport_global, stream_global,
status_code, &slice_details);
}
grpc_chttp2_mark_stream_closed(exec_ctx, transport_global, stream_global,
1, 1, stream_parsing->forced_close_error);
}
if (stream_parsing->received_close) {
grpc_chttp2_mark_stream_closed(exec_ctx, transport_global, stream_global,
1, 0, GRPC_ERROR_NONE);
}
}
}
static grpc_error *update_incoming_window(grpc_exec_ctx *exec_ctx,
grpc_chttp2_transport *t,
grpc_chttp2_stream *s) {
uint32_t incoming_frame_size = t->incoming_frame_size;
if (incoming_frame_size > t->incoming_window) {
char *msg;
gpr_asprintf(&msg, "frame of size %d overflows incoming window of %" PRId64,
t->incoming_frame_size, t->incoming_window);
grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
gpr_free(msg);
return err;
}
if (s != NULL) {
if (incoming_frame_size >
s->incoming_window_delta +
t->settings[GRPC_ACKED_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]) {
if (incoming_frame_size <=
s->incoming_window_delta +
t->settings[GRPC_SENT_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]) {
gpr_log(
GPR_ERROR,
"Incoming frame of size %d exceeds incoming window size of %" PRId64
".\n"
"The (un-acked, future) window size would be %" PRId64
" which is not exceeded.\n"
"This would usually cause a disconnection, but allowing it due to "
"broken HTTP2 implementations in the wild.\n"
"See (for example) https://github.com/netty/netty/issues/6520.",
t->incoming_frame_size,
s->incoming_window_delta +
t->settings[GRPC_ACKED_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE],
s->incoming_window_delta +
t->settings[GRPC_SENT_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]);
} else {
char *msg;
gpr_asprintf(&msg,
"frame of size %d overflows incoming window of %" PRId64,
t->incoming_frame_size,
s->incoming_window_delta +
t->settings[GRPC_ACKED_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]);
grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
gpr_free(msg);
return err;
}
}
GRPC_CHTTP2_FLOW_DEBIT_STREAM_INCOMING_WINDOW_DELTA("parse", t, s,
incoming_frame_size);
if ((int64_t)s->incoming_window_delta - (int64_t)s->announce_window <=
-(int64_t)t->settings[GRPC_SENT_SETTINGS]
[GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE] /
2) {
grpc_chttp2_become_writable(exec_ctx, t, s,
GRPC_CHTTP2_STREAM_WRITE_INITIATE_UNCOVERED,
"window-update-required");
}
s->received_bytes += incoming_frame_size;
}
uint32_t target_incoming_window = grpc_chttp2_target_incoming_window(t);
GRPC_CHTTP2_FLOW_DEBIT_TRANSPORT("parse", t, incoming_window,
incoming_frame_size);
if (t->incoming_window <= target_incoming_window / 2) {
grpc_chttp2_initiate_write(exec_ctx, t, false, "flow_control");
}
return GRPC_ERROR_NONE;
}
