diff options
Diffstat (limited to 'modules/http2/h2_session.c')
| -rw-r--r-- | modules/http2/h2_session.c | 1991 |
1 files changed, 1991 insertions, 0 deletions
diff --git a/modules/http2/h2_session.c b/modules/http2/h2_session.c new file mode 100644 index 0000000..7ba49cf --- /dev/null +++ b/modules/http2/h2_session.c @@ -0,0 +1,1991 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include <assert.h> +#include <stddef.h> +#include <apr_thread_cond.h> +#include <apr_atomic.h> +#include <apr_base64.h> +#include <apr_strings.h> + +#include <ap_mpm.h> + +#include <httpd.h> +#include <http_core.h> +#include <http_config.h> +#include <http_log.h> +#include <http_protocol.h> +#include <scoreboard.h> + +#include <mpm_common.h> + +#if APR_HAVE_UNISTD_H +#include <unistd.h> /* for getpid() */ +#endif + +#include "h2_private.h" +#include "h2.h" +#include "h2_bucket_beam.h" +#include "h2_bucket_eos.h" +#include "h2_config.h" +#include "h2_conn_ctx.h" +#include "h2_protocol.h" +#include "h2_mplx.h" +#include "h2_push.h" +#include "h2_request.h" +#include "h2_headers.h" +#include "h2_stream.h" +#include "h2_c2.h" +#include "h2_session.h" +#include "h2_util.h" +#include "h2_version.h" +#include "h2_workers.h" + + +static void transit(h2_session *session, const char *action, + h2_session_state nstate); + +static void on_stream_state_enter(void *ctx, h2_stream *stream); +static void on_stream_state_event(void *ctx, h2_stream *stream, h2_stream_event_t ev); +static void on_stream_event(void *ctx, h2_stream *stream, h2_stream_event_t ev); + +static int h2_session_status_from_apr_status(apr_status_t rv) +{ + if (rv == APR_SUCCESS) { + return NGHTTP2_NO_ERROR; + } + else if (APR_STATUS_IS_EAGAIN(rv)) { + return NGHTTP2_ERR_WOULDBLOCK; + } + else if (APR_STATUS_IS_EOF(rv)) { + return NGHTTP2_ERR_EOF; + } + return NGHTTP2_ERR_PROTO; +} + +static h2_stream *get_stream(h2_session *session, int stream_id) +{ + return nghttp2_session_get_stream_user_data(session->ngh2, stream_id); +} + +void h2_session_event(h2_session *session, h2_session_event_t ev, + int err, const char *msg) +{ + h2_session_dispatch_event(session, ev, err, msg); +} + +static int rst_unprocessed_stream(h2_stream *stream, void *ctx) +{ + int unprocessed = (!h2_stream_is_at_or_past(stream, H2_SS_CLOSED) + && (H2_STREAM_CLIENT_INITIATED(stream->id)? + (!stream->session->local.accepting + && stream->id > stream->session->local.accepted_max) + : + (!stream->session->remote.accepting + && stream->id > stream->session->remote.accepted_max)) + ); + if (unprocessed) { + h2_stream_rst(stream, H2_ERR_NO_ERROR); + return 0; + } + return 1; +} + +static void cleanup_unprocessed_streams(h2_session *session) +{ + h2_mplx_c1_streams_do(session->mplx, rst_unprocessed_stream, session); +} + +static h2_stream *h2_session_open_stream(h2_session *session, int stream_id, + int initiated_on) +{ + h2_stream * stream; + apr_pool_t *stream_pool; + + apr_pool_create(&stream_pool, session->pool); + apr_pool_tag(stream_pool, "h2_stream"); + + stream = h2_stream_create(stream_id, stream_pool, session, + session->monitor, initiated_on); + if (stream) { + nghttp2_session_set_stream_user_data(session->ngh2, stream_id, stream); + } + return stream; +} + +/** + * Determine the priority order of streams. + * - if both stream depend on the same one, compare weights + * - if one stream is closer to the root, prioritize that one + * - if both are on the same level, use the weight of their root + * level ancestors + */ +static int spri_cmp(int sid1, nghttp2_stream *s1, + int sid2, nghttp2_stream *s2, h2_session *session) +{ + nghttp2_stream *p1, *p2; + + p1 = nghttp2_stream_get_parent(s1); + p2 = nghttp2_stream_get_parent(s2); + + if (p1 == p2) { + int32_t w1, w2; + + w1 = nghttp2_stream_get_weight(s1); + w2 = nghttp2_stream_get_weight(s2); + return w2 - w1; + } + else if (!p1) { + /* stream 1 closer to root */ + return -1; + } + else if (!p2) { + /* stream 2 closer to root */ + return 1; + } + return spri_cmp(sid1, p1, sid2, p2, session); +} + +static int stream_pri_cmp(int sid1, int sid2, void *ctx) +{ + h2_session *session = ctx; + nghttp2_stream *s1, *s2; + + s1 = nghttp2_session_find_stream(session->ngh2, sid1); + s2 = nghttp2_session_find_stream(session->ngh2, sid2); + + if (s1 == s2) { + return 0; + } + else if (!s1) { + return 1; + } + else if (!s2) { + return -1; + } + return spri_cmp(sid1, s1, sid2, s2, session); +} + +/* + * Callback when nghttp2 wants to send bytes back to the client. + */ +static ssize_t send_cb(nghttp2_session *ngh2, + const uint8_t *data, size_t length, + int flags, void *userp) +{ + h2_session *session = (h2_session *)userp; + apr_status_t rv; + (void)ngh2; + (void)flags; + + if (h2_c1_io_needs_flush(&session->io)) { + return NGHTTP2_ERR_WOULDBLOCK; + } + + rv = h2_c1_io_add_data(&session->io, (const char *)data, length); + if (APR_SUCCESS == rv) { + return length; + } + else if (APR_STATUS_IS_EAGAIN(rv)) { + return NGHTTP2_ERR_WOULDBLOCK; + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, rv, session->c1, + APLOGNO(03062) "h2_session: send error"); + return h2_session_status_from_apr_status(rv); + } +} + +static int on_invalid_frame_recv_cb(nghttp2_session *ngh2, + const nghttp2_frame *frame, + int error, void *userp) +{ + h2_session *session = (h2_session *)userp; + (void)ngh2; + + if (APLOGcdebug(session->c1)) { + char buffer[256]; + + h2_util_frame_print(frame, buffer, sizeof(buffer)/sizeof(buffer[0])); + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03063), session, + "recv invalid FRAME[%s], frames=%ld/%ld (r/s)"), + buffer, (long)session->frames_received, + (long)session->frames_sent); + } + return 0; +} + +static int on_data_chunk_recv_cb(nghttp2_session *ngh2, uint8_t flags, + int32_t stream_id, + const uint8_t *data, size_t len, void *userp) +{ + h2_session *session = (h2_session *)userp; + apr_status_t status = APR_EINVAL; + h2_stream * stream; + int rv = 0; + + stream = get_stream(session, stream_id); + if (stream) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_STRM_MSG(session, stream_id, "write %ld bytes of DATA"), + (long)len); + status = h2_stream_recv_DATA(stream, flags, data, len); + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, APLOGNO(03064) + H2_SSSN_STRM_MSG(session, stream_id, + "on_data_chunk for unknown stream")); + rv = NGHTTP2_ERR_CALLBACK_FAILURE; + } + + if (status != APR_SUCCESS) { + /* count this as consumed explicitly as no one will read it */ + nghttp2_session_consume(session->ngh2, stream_id, len); + } + return rv; +} + +static int on_stream_close_cb(nghttp2_session *ngh2, int32_t stream_id, + uint32_t error_code, void *userp) +{ + h2_session *session = (h2_session *)userp; + h2_stream *stream; + + (void)ngh2; + stream = get_stream(session, stream_id); + if (stream) { + if (error_code) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(03065), stream, + "closing with err=%d %s"), + (int)error_code, h2_protocol_err_description(error_code)); + h2_stream_rst(stream, error_code); + } + } + return 0; +} + +static int on_begin_headers_cb(nghttp2_session *ngh2, + const nghttp2_frame *frame, void *userp) +{ + h2_session *session = (h2_session *)userp; + h2_stream *s = NULL; + + /* We may see HEADERs at the start of a stream or after all DATA + * streams to carry trailers. */ + (void)ngh2; + s = get_stream(session, frame->hd.stream_id); + if (s) { + /* nop */ + } + else if (session->local.accepting) { + s = h2_session_open_stream(userp, frame->hd.stream_id, 0); + } + return s? 0 : NGHTTP2_ERR_START_STREAM_NOT_ALLOWED; +} + +static int on_header_cb(nghttp2_session *ngh2, const nghttp2_frame *frame, + const uint8_t *name, size_t namelen, + const uint8_t *value, size_t valuelen, + uint8_t flags, + void *userp) +{ + h2_session *session = (h2_session *)userp; + h2_stream * stream; + apr_status_t status; + + (void)flags; + stream = get_stream(session, frame->hd.stream_id); + if (!stream) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, APLOGNO(02920) + H2_SSSN_STRM_MSG(session, frame->hd.stream_id, + "on_header unknown stream")); + return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE; + } + + status = h2_stream_add_header(stream, (const char *)name, namelen, + (const char *)value, valuelen); + if (status != APR_SUCCESS + && (!stream->rtmp + || stream->rtmp->http_status == H2_HTTP_STATUS_UNSET)) { + return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE; + } + return 0; +} + +/** + * nghttp2 session has received a complete frame. Most are used by nghttp2 + * for processing of internal state. Some, like HEADER and DATA frames, + * we need to act on. + */ +static int on_frame_recv_cb(nghttp2_session *ng2s, + const nghttp2_frame *frame, + void *userp) +{ + h2_session *session = (h2_session *)userp; + h2_stream *stream; + apr_status_t rv = APR_SUCCESS; + + stream = frame->hd.stream_id? get_stream(session, frame->hd.stream_id) : NULL; + if (APLOGcdebug(session->c1)) { + char buffer[256]; + + h2_util_frame_print(frame, buffer, sizeof(buffer)/sizeof(buffer[0])); + if (stream) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(10302), stream, + "recv FRAME[%s], frames=%ld/%ld (r/s)"), + buffer, (long)session->frames_received, + (long)session->frames_sent); + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03066), session, + "recv FRAME[%s], frames=%ld/%ld (r/s)"), + buffer, (long)session->frames_received, + (long)session->frames_sent); + } + } + + ++session->frames_received; + switch (frame->hd.type) { + case NGHTTP2_HEADERS: + /* This can be HEADERS for a new stream, defining the request, + * or HEADER may come after DATA at the end of a stream as in + * trailers */ + if (stream) { + rv = h2_stream_recv_frame(stream, NGHTTP2_HEADERS, frame->hd.flags, + frame->hd.length + H2_FRAME_HDR_LEN); + } + break; + case NGHTTP2_DATA: + if (stream) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(02923), stream, + "DATA, len=%ld, flags=%d"), + (long)frame->hd.length, frame->hd.flags); + rv = h2_stream_recv_frame(stream, NGHTTP2_DATA, frame->hd.flags, + frame->hd.length + H2_FRAME_HDR_LEN); + } + break; + case NGHTTP2_PRIORITY: + session->reprioritize = 1; + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_STRM_MSG(session, frame->hd.stream_id, "PRIORITY frame " + " weight=%d, dependsOn=%d, exclusive=%d"), + frame->priority.pri_spec.weight, + frame->priority.pri_spec.stream_id, + frame->priority.pri_spec.exclusive); + break; + case NGHTTP2_WINDOW_UPDATE: + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_STRM_MSG(session, frame->hd.stream_id, + "WINDOW_UPDATE incr=%d"), + frame->window_update.window_size_increment); + break; + case NGHTTP2_RST_STREAM: + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, APLOGNO(03067) + H2_SSSN_STRM_MSG(session, frame->hd.stream_id, + "RST_STREAM by client, error=%d"), + (int)frame->rst_stream.error_code); + if (stream && stream->initiated_on) { + /* A stream reset on a request we sent it. Normal, when the + * client does not want it. */ + ++session->pushes_reset; + } + else { + /* A stream reset on a request it sent us. Could happen in a browser + * when the user navigates away or cancels loading - maybe. */ + h2_mplx_c1_client_rst(session->mplx, frame->hd.stream_id); + } + ++session->streams_reset; + break; + case NGHTTP2_GOAWAY: + if (frame->goaway.error_code == 0 + && frame->goaway.last_stream_id == ((1u << 31) - 1)) { + /* shutdown notice. Should not come from a client... */ + session->remote.accepting = 0; + } + else { + session->remote.accepted_max = frame->goaway.last_stream_id; + h2_session_dispatch_event(session, H2_SESSION_EV_REMOTE_GOAWAY, + frame->goaway.error_code, NULL); + } + break; + case NGHTTP2_SETTINGS: + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_MSG(session, "SETTINGS, len=%ld"), (long)frame->hd.length); + break; + default: + if (APLOGctrace2(session->c1)) { + char buffer[256]; + + h2_util_frame_print(frame, buffer, + sizeof(buffer)/sizeof(buffer[0])); + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_MSG(session, "on_frame_rcv %s"), buffer); + } + break; + } + + if (session->state == H2_SESSION_ST_IDLE) { + /* We received a frame, but session is in state IDLE. That means the frame + * did not really progress any of the (possibly) open streams. It was a meta + * frame, e.g. SETTINGS/WINDOW_UPDATE/unknown/etc. + * Remember: IDLE means we cannot send because either there are no streams open or + * all open streams are blocked on exhausted WINDOWs for outgoing data. + * The more frames we receive that do not change this, the less interested we + * become in serving this connection. This is expressed in increasing "idle_delays". + * Eventually, the connection will timeout and we'll close it. */ + session->idle_frames = H2MIN(session->idle_frames + 1, session->frames_received); + ap_log_cerror( APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_SSSN_MSG(session, "session has %ld idle frames"), + (long)session->idle_frames); + if (session->idle_frames > 10) { + apr_size_t busy_frames = H2MAX(session->frames_received - session->idle_frames, 1); + int idle_ratio = (int)(session->idle_frames / busy_frames); + if (idle_ratio > 100) { + session->idle_delay = apr_time_from_msec(H2MIN(1000, idle_ratio)); + } + else if (idle_ratio > 10) { + session->idle_delay = apr_time_from_msec(10); + } + else if (idle_ratio > 1) { + session->idle_delay = apr_time_from_msec(1); + } + else { + session->idle_delay = 0; + } + } + } + + if (APR_SUCCESS != rv) return NGHTTP2_ERR_PROTO; + return 0; +} + +static char immortal_zeros[H2_MAX_PADLEN]; + +static int on_send_data_cb(nghttp2_session *ngh2, + nghttp2_frame *frame, + const uint8_t *framehd, + size_t length, + nghttp2_data_source *source, + void *userp) +{ + apr_status_t status = APR_SUCCESS; + h2_session *session = (h2_session *)userp; + int stream_id = (int)frame->hd.stream_id; + unsigned char padlen; + int eos; + h2_stream *stream; + apr_bucket *b; + apr_off_t len = length; + + (void)ngh2; + (void)source; + ap_assert(frame->data.padlen <= (H2_MAX_PADLEN+1)); + padlen = (unsigned char)frame->data.padlen; + + stream = get_stream(session, stream_id); + if (!stream) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, APR_NOTFOUND, session->c1, + APLOGNO(02924) + H2_SSSN_STRM_MSG(session, stream_id, "send_data, stream not found")); + return NGHTTP2_ERR_CALLBACK_FAILURE; + } + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "send_data_cb for %ld bytes"), + (long)length); + + status = h2_c1_io_add_data(&session->io, (const char *)framehd, H2_FRAME_HDR_LEN); + if (padlen && status == APR_SUCCESS) { + --padlen; + status = h2_c1_io_add_data(&session->io, (const char *)&padlen, 1); + } + + if (status != APR_SUCCESS) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, status, session->c1, + H2_STRM_MSG(stream, "writing frame header")); + return NGHTTP2_ERR_CALLBACK_FAILURE; + } + + status = h2_stream_read_to(stream, session->bbtmp, &len, &eos); + if (status != APR_SUCCESS) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, status, session->c1, + H2_STRM_MSG(stream, "send_data_cb, reading stream")); + apr_brigade_cleanup(session->bbtmp); + return NGHTTP2_ERR_CALLBACK_FAILURE; + } + else if (len != (apr_off_t)length) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, status, session->c1, + H2_STRM_MSG(stream, "send_data_cb, wanted %ld bytes, " + "got %ld from stream"), (long)length, (long)len); + apr_brigade_cleanup(session->bbtmp); + return NGHTTP2_ERR_CALLBACK_FAILURE; + } + + if (padlen) { + b = apr_bucket_immortal_create(immortal_zeros, padlen, + session->c1->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(session->bbtmp, b); + } + + status = h2_c1_io_append(&session->io, session->bbtmp); + apr_brigade_cleanup(session->bbtmp); + + if (status == APR_SUCCESS) { + stream->out_data_frames++; + stream->out_data_octets += length; + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "sent data length=%ld, total=%ld"), + (long)length, (long)stream->out_data_octets); + return 0; + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, session->c1, + H2_STRM_LOG(APLOGNO(02925), stream, "failed send_data_cb")); + return NGHTTP2_ERR_CALLBACK_FAILURE; + } +} + +static int on_frame_send_cb(nghttp2_session *ngh2, + const nghttp2_frame *frame, + void *user_data) +{ + h2_session *session = user_data; + h2_stream *stream; + int stream_id = frame->hd.stream_id; + + ++session->frames_sent; + switch (frame->hd.type) { + case NGHTTP2_PUSH_PROMISE: + /* PUSH_PROMISE we report on the promised stream */ + stream_id = frame->push_promise.promised_stream_id; + break; + default: + break; + } + + stream = get_stream(session, stream_id); + if (APLOGcdebug(session->c1)) { + char buffer[256]; + + h2_util_frame_print(frame, buffer, sizeof(buffer)/sizeof(buffer[0])); + if (stream) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(10303), stream, + "sent FRAME[%s], frames=%ld/%ld (r/s)"), + buffer, (long)session->frames_received, + (long)session->frames_sent); + } + else { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03068), session, + "sent FRAME[%s], frames=%ld/%ld (r/s)"), + buffer, (long)session->frames_received, + (long)session->frames_sent); + } + } + + if (stream) { + h2_stream_send_frame(stream, frame->hd.type, frame->hd.flags, + frame->hd.length + H2_FRAME_HDR_LEN); + } + return 0; +} + +#ifdef H2_NG2_INVALID_HEADER_CB +static int on_invalid_header_cb(nghttp2_session *ngh2, + const nghttp2_frame *frame, + const uint8_t *name, size_t namelen, + const uint8_t *value, size_t valuelen, + uint8_t flags, void *user_data) +{ + h2_session *session = user_data; + h2_stream *stream; + + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, APLOGNO(03456) + H2_SSSN_STRM_MSG(session, frame->hd.stream_id, + "invalid header '%s: %s'"), + apr_pstrndup(session->pool, (const char *)name, namelen), + apr_pstrndup(session->pool, (const char *)value, valuelen)); + stream = get_stream(session, frame->hd.stream_id); + if (stream) { + h2_stream_rst(stream, NGHTTP2_PROTOCOL_ERROR); + } + return 0; +} +#endif + +static ssize_t select_padding_cb(nghttp2_session *ngh2, + const nghttp2_frame *frame, + size_t max_payloadlen, void *user_data) +{ + h2_session *session = user_data; + size_t frame_len = frame->hd.length + H2_FRAME_HDR_LEN; /* the total length without padding */ + size_t padded_len = frame_len; + + /* Determine # of padding bytes to append to frame. Unless session->padding_always + * the number my be capped by the ui.write_size that currently applies. + */ + if (session->padding_max) { + int n = ap_random_pick(0, session->padding_max); + padded_len = H2MIN(max_payloadlen + H2_FRAME_HDR_LEN, frame_len + n); + } + + if (padded_len != frame_len) { + if (!session->padding_always && session->io.write_size + && (padded_len > session->io.write_size) + && (frame_len <= session->io.write_size)) { + padded_len = session->io.write_size; + } + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + "select padding from [%d, %d]: %d (frame length: 0x%04x, write size: %d)", + (int)frame_len, (int)max_payloadlen+H2_FRAME_HDR_LEN, + (int)(padded_len - frame_len), (int)padded_len, (int)session->io.write_size); + return padded_len - H2_FRAME_HDR_LEN; + } + return frame->hd.length; +} + +#define NGH2_SET_CALLBACK(callbacks, name, fn)\ +nghttp2_session_callbacks_set_##name##_callback(callbacks, fn) + +static apr_status_t init_callbacks(conn_rec *c, nghttp2_session_callbacks **pcb) +{ + int rv = nghttp2_session_callbacks_new(pcb); + if (rv != 0) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, 0, c, + APLOGNO(02926) "nghttp2_session_callbacks_new: %s", + nghttp2_strerror(rv)); + return APR_EGENERAL; + } + + NGH2_SET_CALLBACK(*pcb, send, send_cb); + NGH2_SET_CALLBACK(*pcb, on_frame_recv, on_frame_recv_cb); + NGH2_SET_CALLBACK(*pcb, on_invalid_frame_recv, on_invalid_frame_recv_cb); + NGH2_SET_CALLBACK(*pcb, on_data_chunk_recv, on_data_chunk_recv_cb); + NGH2_SET_CALLBACK(*pcb, on_stream_close, on_stream_close_cb); + NGH2_SET_CALLBACK(*pcb, on_begin_headers, on_begin_headers_cb); + NGH2_SET_CALLBACK(*pcb, on_header, on_header_cb); + NGH2_SET_CALLBACK(*pcb, send_data, on_send_data_cb); + NGH2_SET_CALLBACK(*pcb, on_frame_send, on_frame_send_cb); +#ifdef H2_NG2_INVALID_HEADER_CB + NGH2_SET_CALLBACK(*pcb, on_invalid_header, on_invalid_header_cb); +#endif + NGH2_SET_CALLBACK(*pcb, select_padding, select_padding_cb); + return APR_SUCCESS; +} + +static void update_child_status(h2_session *session, int status, + const char *msg, const h2_stream *stream) +{ + /* Assume that we also change code/msg when something really happened and + * avoid updating the scoreboard in between */ + if (session->last_status_code != status + || session->last_status_msg != msg) { + char sbuffer[1024]; + sbuffer[0] = '\0'; + if (stream) { + apr_snprintf(sbuffer, sizeof(sbuffer), + ": stream %d, %s %s", + stream->id, + stream->request? stream->request->method : "", + stream->request? stream->request->path : ""); + } + apr_snprintf(session->status, sizeof(session->status), + "[%d/%d] %s%s", + (int)(session->remote.emitted_count + session->pushes_submitted), + (int)session->streams_done, + msg? msg : "-", sbuffer); + ap_update_child_status_from_server(session->c1->sbh, status, + session->c1, session->s); + ap_update_child_status_descr(session->c1->sbh, status, session->status); + } +} + +static apr_status_t h2_session_shutdown_notice(h2_session *session) +{ + apr_status_t status; + + ap_assert(session); + if (!session->local.accepting) { + return APR_SUCCESS; + } + + nghttp2_submit_shutdown_notice(session->ngh2); + session->local.accepting = 0; + status = nghttp2_session_send(session->ngh2); + if (status == APR_SUCCESS) { + status = h2_c1_io_assure_flushed(&session->io); + } + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03457), session, "sent shutdown notice")); + return status; +} + +static apr_status_t h2_session_shutdown(h2_session *session, int error, + const char *msg, int force_close) +{ + apr_status_t status = APR_SUCCESS; + + ap_assert(session); + if (session->local.shutdown) { + return APR_SUCCESS; + } + + if (error && !msg) { + if (APR_STATUS_IS_EPIPE(error)) { + msg = "remote close"; + } + } + + if (error || force_close) { + /* not a graceful shutdown, we want to leave... + * Do not start further streams that are waiting to be scheduled. + * Find out the max stream id that we habe been processed or + * are still actively working on. + * Remove all streams greater than this number without submitting + * a RST_STREAM frame, since that should be clear from the GOAWAY + * we send. */ + session->local.accepted_max = h2_mplx_c1_shutdown(session->mplx); + session->local.error = error; + session->local.error_msg = msg; + } + else { + /* graceful shutdown. we will continue processing all streams + * we have, but no longer accept new ones. Report the max stream + * we have received and discard all new ones. */ + } + + session->local.accepting = 0; + session->local.shutdown = 1; + if (!session->c1->aborted) { + nghttp2_submit_goaway(session->ngh2, NGHTTP2_FLAG_NONE, + session->local.accepted_max, + error, (uint8_t*)msg, msg? strlen(msg):0); + status = nghttp2_session_send(session->ngh2); + if (status == APR_SUCCESS) { + status = h2_c1_io_assure_flushed(&session->io); + } + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03069), session, + "sent GOAWAY, err=%d, msg=%s"), error, msg? msg : ""); + } + h2_session_dispatch_event(session, H2_SESSION_EV_LOCAL_GOAWAY, error, msg); + return status; +} + +static apr_status_t session_cleanup(h2_session *session, const char *trigger) +{ + conn_rec *c = session->c1; + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, c, + H2_SSSN_MSG(session, "pool_cleanup")); + + if (session->state != H2_SESSION_ST_DONE + && session->state != H2_SESSION_ST_INIT) { + /* Not good. The connection is being torn down and we have + * not sent a goaway. This is considered a protocol error and + * the client has to assume that any streams "in flight" may have + * been processed and are not safe to retry. + * As clients with idle connection may only learn about a closed + * connection when sending the next request, this has the effect + * that at least this one request will fail. + */ + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, + H2_SSSN_LOG(APLOGNO(03199), session, + "connection disappeared without proper " + "goodbye, clients will be confused, should not happen")); + } + + transit(session, trigger, H2_SESSION_ST_CLEANUP); + h2_mplx_c1_destroy(session->mplx); + session->mplx = NULL; + + ap_assert(session->ngh2); + nghttp2_session_del(session->ngh2); + session->ngh2 = NULL; + h2_conn_ctx_detach(c); + + return APR_SUCCESS; +} + +static apr_status_t session_pool_cleanup(void *data) +{ + conn_rec *c = data; + h2_conn_ctx_t *conn_ctx = h2_conn_ctx_get(c); + h2_session *session = conn_ctx? conn_ctx->session : NULL; + + if (session) { + int mpm_state = 0; + int level; + + ap_mpm_query(AP_MPMQ_MPM_STATE, &mpm_state); + level = (AP_MPMQ_STOPPING == mpm_state)? APLOG_DEBUG : APLOG_WARNING; + /* if the session is still there, now is the last chance + * to perform cleanup. Normally, cleanup should have happened + * earlier in the connection pre_close. + * However, when the server is stopping, it may shutdown connections + * without running the pre_close hooks. Do not want about that. */ + ap_log_cerror(APLOG_MARK, level, 0, c, + H2_SSSN_LOG(APLOGNO(10020), session, + "session cleanup triggered by pool cleanup. " + "this should have happened earlier already.")); + return session_cleanup(session, "pool cleanup"); + } + return APR_SUCCESS; +} + +static /* atomic */ apr_uint32_t next_id; + +apr_status_t h2_session_create(h2_session **psession, conn_rec *c, request_rec *r, + server_rec *s, h2_workers *workers) +{ + nghttp2_session_callbacks *callbacks = NULL; + nghttp2_option *options = NULL; + uint32_t n; + int thread_num; + apr_pool_t *pool = NULL; + h2_session *session; + h2_stream *stream0; + apr_status_t status; + int rv; + + *psession = NULL; + apr_pool_create(&pool, c->pool); + apr_pool_tag(pool, "h2_session"); + session = apr_pcalloc(pool, sizeof(h2_session)); + if (!session) { + return APR_ENOMEM; + } + + *psession = session; + /* c->id does not give a unique id for the lifetime of the session. + * mpms like event change c->id when re-activating a keepalive + * connection based on the child_num+thread_num of the worker + * processing it. + * We'd like to have an id that remains constant and unique bc + * h2 streams can live through keepalive periods. While double id + * will not lead to processing failures, it will confuse log analysis. + */ +#if AP_MODULE_MAGIC_AT_LEAST(20211221, 8) + ap_sb_get_child_thread(c->sbh, &session->child_num, &thread_num); +#else + (void)thread_num; + session->child_num = (int)getpid(); +#endif + session->id = apr_atomic_inc32(&next_id); + session->c1 = c; + session->r = r; + session->s = s; + session->pool = pool; + session->workers = workers; + + session->state = H2_SESSION_ST_INIT; + session->local.accepting = 1; + session->remote.accepting = 1; + + session->max_stream_count = h2_config_sgeti(s, H2_CONF_MAX_STREAMS); + session->max_stream_mem = h2_config_sgeti(s, H2_CONF_STREAM_MAX_MEM); + + session->out_c1_blocked = h2_iq_create(session->pool, (int)session->max_stream_count); + session->ready_to_process = h2_iq_create(session->pool, (int)session->max_stream_count); + + session->monitor = apr_pcalloc(pool, sizeof(h2_stream_monitor)); + session->monitor->ctx = session; + session->monitor->on_state_enter = on_stream_state_enter; + session->monitor->on_state_event = on_stream_state_event; + session->monitor->on_event = on_stream_event; + + stream0 = h2_stream_create(0, session->pool, session, NULL, 0); + stream0->c2 = session->c1; /* stream0's connection is the main connection */ + session->mplx = h2_mplx_c1_create(session->child_num, session->id, + stream0, s, session->pool, workers); + if (!session->mplx) { + apr_pool_destroy(pool); + return APR_ENOTIMPL; + } + + h2_c1_io_init(&session->io, session); + session->padding_max = h2_config_sgeti(s, H2_CONF_PADDING_BITS); + if (session->padding_max) { + session->padding_max = (0x01 << session->padding_max) - 1; + } + session->padding_always = h2_config_sgeti(s, H2_CONF_PADDING_ALWAYS); + session->bbtmp = apr_brigade_create(session->pool, c->bucket_alloc); + + status = init_callbacks(c, &callbacks); + if (status != APR_SUCCESS) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, status, c, APLOGNO(02927) + "nghttp2: error in init_callbacks"); + apr_pool_destroy(pool); + return status; + } + + rv = nghttp2_option_new(&options); + if (rv != 0) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, APR_EGENERAL, c, + APLOGNO(02928) "nghttp2_option_new: %s", + nghttp2_strerror(rv)); + apr_pool_destroy(pool); + return status; + } + nghttp2_option_set_peer_max_concurrent_streams(options, (uint32_t)session->max_stream_count); + /* We need to handle window updates ourself, otherwise we + * get flooded by nghttp2. */ + nghttp2_option_set_no_auto_window_update(options, 1); +#ifdef H2_NG2_NO_CLOSED_STREAMS + /* We do not want nghttp2 to keep information about closed streams as + * that accumulates memory on long connections. This makes PRIORITY + * setting in relation to older streams non-working. */ + nghttp2_option_set_no_closed_streams(options, 1); +#endif +#ifdef H2_NG2_RFC9113_STRICTNESS + /* nghttp2 v1.50.0 introduces the strictness checks on leading/trailing + * whitespace of RFC 9113 for fields. But, by default, it RST streams + * carrying such. We do not want that. We want to strip the ws and + * handle them, just like the HTTP/1.1 parser does. */ + nghttp2_option_set_no_rfc9113_leading_and_trailing_ws_validation(options, 1); +#endif + rv = nghttp2_session_server_new2(&session->ngh2, callbacks, + session, options); + nghttp2_session_callbacks_del(callbacks); + nghttp2_option_del(options); + + if (rv != 0) { + ap_log_cerror(APLOG_MARK, APLOG_ERR, APR_EGENERAL, c, + APLOGNO(02929) "nghttp2_session_server_new: %s", + nghttp2_strerror(rv)); + apr_pool_destroy(pool); + return APR_ENOMEM; + } + + n = h2_config_sgeti(s, H2_CONF_PUSH_DIARY_SIZE); + session->push_diary = h2_push_diary_create(session->pool, n); + + if (APLOGcdebug(c)) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, + H2_SSSN_LOG(APLOGNO(03200), session, + "created, max_streams=%d, stream_mem=%d, " + "workers_limit=%d, workers_max=%d, " + "push_diary(type=%d,N=%d)"), + (int)session->max_stream_count, + (int)session->max_stream_mem, + session->mplx->processing_limit, + session->mplx->processing_max, + session->push_diary->dtype, + (int)session->push_diary->N); + } + + apr_pool_pre_cleanup_register(pool, c, session_pool_cleanup); + + return APR_SUCCESS; +} + +static apr_status_t h2_session_start(h2_session *session, int *rv) +{ + apr_status_t status = APR_SUCCESS; + nghttp2_settings_entry settings[3]; + size_t slen; + int win_size; + + ap_assert(session); + /* Start the conversation by submitting our SETTINGS frame */ + *rv = 0; + if (session->r) { + const char *s, *cs; + apr_size_t dlen; + h2_stream * stream; + + /* 'h2c' mode: we should have a 'HTTP2-Settings' header with + * base64 encoded client settings. */ + s = apr_table_get(session->r->headers_in, "HTTP2-Settings"); + if (!s) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, APR_EINVAL, session->r, + APLOGNO(02931) + "HTTP2-Settings header missing in request"); + return APR_EINVAL; + } + cs = NULL; + dlen = h2_util_base64url_decode(&cs, s, session->pool); + + if (APLOGrdebug(session->r)) { + char buffer[128]; + h2_util_hex_dump(buffer, 128, (char*)cs, dlen); + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, session->r, APLOGNO(03070) + "upgrading h2c session with HTTP2-Settings: %s -> %s (%d)", + s, buffer, (int)dlen); + } + + *rv = nghttp2_session_upgrade(session->ngh2, (uint8_t*)cs, dlen, NULL); + if (*rv != 0) { + status = APR_EINVAL; + ap_log_rerror(APLOG_MARK, APLOG_ERR, status, session->r, + APLOGNO(02932) "nghttp2_session_upgrade: %s", + nghttp2_strerror(*rv)); + return status; + } + + /* Now we need to auto-open stream 1 for the request we got. */ + stream = h2_session_open_stream(session, 1, 0); + if (!stream) { + status = APR_EGENERAL; + ap_log_rerror(APLOG_MARK, APLOG_ERR, status, session->r, + APLOGNO(02933) "open stream 1: %s", + nghttp2_strerror(*rv)); + return status; + } + + status = h2_stream_set_request_rec(stream, session->r, 1); + if (status != APR_SUCCESS) { + return status; + } + } + + slen = 0; + settings[slen].settings_id = NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS; + settings[slen].value = (uint32_t)session->max_stream_count; + ++slen; + win_size = h2_config_sgeti(session->s, H2_CONF_WIN_SIZE); + if (win_size != H2_INITIAL_WINDOW_SIZE) { + settings[slen].settings_id = NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE; + settings[slen].value = win_size; + ++slen; + } + + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, session->c1, + H2_SSSN_LOG(APLOGNO(03201), session, + "start, INITIAL_WINDOW_SIZE=%ld, MAX_CONCURRENT_STREAMS=%d"), + (long)win_size, (int)session->max_stream_count); + *rv = nghttp2_submit_settings(session->ngh2, NGHTTP2_FLAG_NONE, + settings, slen); + if (*rv != 0) { + status = APR_EGENERAL; + ap_log_cerror(APLOG_MARK, APLOG_ERR, status, session->c1, + H2_SSSN_LOG(APLOGNO(02935), session, + "nghttp2_submit_settings: %s"), nghttp2_strerror(*rv)); + } + else { + /* use maximum possible value for connection window size. We are only + * interested in per stream flow control. which have the initial window + * size configured above. + * Therefore, for our use, the connection window can only get in the + * way. Example: if we allow 100 streams with a 32KB window each, we + * buffer up to 3.2 MB of data. Unless we do separate connection window + * interim updates, any smaller connection window will lead to blocking + * in DATA flow. + */ + *rv = nghttp2_submit_window_update(session->ngh2, NGHTTP2_FLAG_NONE, + 0, NGHTTP2_MAX_WINDOW_SIZE - win_size); + if (*rv != 0) { + status = APR_EGENERAL; + ap_log_cerror(APLOG_MARK, APLOG_ERR, status, session->c1, + H2_SSSN_LOG(APLOGNO(02970), session, + "nghttp2_submit_window_update: %s"), + nghttp2_strerror(*rv)); + } + } + + return status; +} + +struct h2_stream *h2_session_push(h2_session *session, h2_stream *is, + h2_push *push) +{ + h2_stream *stream; + h2_ngheader *ngh; + apr_status_t status; + int nid = 0; + + status = h2_req_create_ngheader(&ngh, is->pool, push->req); + if (status == APR_SUCCESS) { + nid = nghttp2_submit_push_promise(session->ngh2, 0, is->id, + ngh->nv, ngh->nvlen, NULL); + } + if (status != APR_SUCCESS || nid <= 0) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, session->c1, + H2_STRM_LOG(APLOGNO(03075), is, + "submitting push promise fail: %s"), nghttp2_strerror(nid)); + return NULL; + } + ++session->pushes_promised; + + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(03076), is, "SERVER_PUSH %d for %s %s on %d"), + nid, push->req->method, push->req->path, is->id); + + stream = h2_session_open_stream(session, nid, is->id); + if (!stream) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(03077), is, + "failed to create stream obj %d"), nid); + /* kill the push_promise */ + nghttp2_submit_rst_stream(session->ngh2, NGHTTP2_FLAG_NONE, nid, + NGHTTP2_INTERNAL_ERROR); + return NULL; + } + + h2_session_set_prio(session, stream, push->priority); + h2_stream_set_request(stream, push->req); + return stream; +} + +static int valid_weight(float f) +{ + int w = (int)f; + return (w < NGHTTP2_MIN_WEIGHT? NGHTTP2_MIN_WEIGHT : + (w > NGHTTP2_MAX_WEIGHT)? NGHTTP2_MAX_WEIGHT : w); +} + +apr_status_t h2_session_set_prio(h2_session *session, h2_stream *stream, + const h2_priority *prio) +{ + apr_status_t status = APR_SUCCESS; + nghttp2_stream *s_grandpa, *s_parent, *s; + + if (prio == NULL) { + /* we treat this as a NOP */ + return APR_SUCCESS; + } + s = nghttp2_session_find_stream(session->ngh2, stream->id); + if (!s) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c1, + H2_STRM_MSG(stream, "lookup of nghttp2_stream failed")); + return APR_EINVAL; + } + + s_parent = nghttp2_stream_get_parent(s); + if (s_parent) { + nghttp2_priority_spec ps; + int id_parent, id_grandpa, w_parent, w; + int rv = 0; + const char *ptype = "AFTER"; + h2_dependency dep = prio->dependency; + + id_parent = nghttp2_stream_get_stream_id(s_parent); + s_grandpa = nghttp2_stream_get_parent(s_parent); + if (s_grandpa) { + id_grandpa = nghttp2_stream_get_stream_id(s_grandpa); + } + else { + /* parent of parent does not exist, + * only possible if parent == root */ + dep = H2_DEPENDANT_AFTER; + } + + switch (dep) { + case H2_DEPENDANT_INTERLEAVED: + /* PUSHed stream is to be interleaved with initiating stream. + * It is made a sibling of the initiating stream and gets a + * proportional weight [1, MAX_WEIGHT] of the initiaing + * stream weight. + */ + ptype = "INTERLEAVED"; + w_parent = nghttp2_stream_get_weight(s_parent); + w = valid_weight(w_parent * ((float)prio->weight / NGHTTP2_MAX_WEIGHT)); + nghttp2_priority_spec_init(&ps, id_grandpa, w, 0); + break; + + case H2_DEPENDANT_BEFORE: + /* PUSHed stream os to be sent BEFORE the initiating stream. + * It gets the same weight as the initiating stream, replaces + * that stream in the dependency tree and has the initiating + * stream as child. + */ + ptype = "BEFORE"; + w = w_parent = nghttp2_stream_get_weight(s_parent); + nghttp2_priority_spec_init(&ps, stream->id, w_parent, 0); + id_grandpa = nghttp2_stream_get_stream_id(s_grandpa); + rv = nghttp2_session_change_stream_priority(session->ngh2, id_parent, &ps); + if (rv < 0) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, APLOGNO(03202) + H2_SSSN_STRM_MSG(session, id_parent, + "PUSH BEFORE, weight=%d, depends=%d, returned=%d"), + ps.weight, ps.stream_id, rv); + return APR_EGENERAL; + } + nghttp2_priority_spec_init(&ps, id_grandpa, w, 0); + break; + + case H2_DEPENDANT_AFTER: + /* The PUSHed stream is to be sent after the initiating stream. + * Give if the specified weight and let it depend on the intiating + * stream. + */ + /* fall through, it's the default */ + default: + nghttp2_priority_spec_init(&ps, id_parent, valid_weight(prio->weight), 0); + break; + } + + + rv = nghttp2_session_change_stream_priority(session->ngh2, stream->id, &ps); + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(03203), stream, + "PUSH %s, weight=%d, depends=%d, returned=%d"), + ptype, ps.weight, ps.stream_id, rv); + status = (rv < 0)? APR_EGENERAL : APR_SUCCESS; + } + + return status; +} + +int h2_session_push_enabled(h2_session *session) +{ + /* iff we can and they can and want */ + return (session->remote.accepting /* remote GOAWAY received */ + && h2_config_sgeti(session->s, H2_CONF_PUSH) + && nghttp2_session_get_remote_settings(session->ngh2, + NGHTTP2_SETTINGS_ENABLE_PUSH)); +} + +static int h2_session_want_send(h2_session *session) +{ + return nghttp2_session_want_write(session->ngh2) + || h2_c1_io_pending(&session->io); +} + +static apr_status_t h2_session_send(h2_session *session) +{ + int ngrv, pending = 0; + apr_status_t rv = APR_SUCCESS; + + while (nghttp2_session_want_write(session->ngh2)) { + ngrv = nghttp2_session_send(session->ngh2); + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + "nghttp2_session_send: %d", (int)ngrv); + pending = 1; + if (ngrv != 0 && ngrv != NGHTTP2_ERR_WOULDBLOCK) { + if (nghttp2_is_fatal(ngrv)) { + h2_session_dispatch_event(session, H2_SESSION_EV_PROTO_ERROR, + ngrv, nghttp2_strerror(ngrv)); + rv = APR_EGENERAL; + goto cleanup; + } + } + if (h2_c1_io_needs_flush(&session->io)) { + rv = h2_c1_io_assure_flushed(&session->io); + pending = 0; + } + } + if (pending) { + rv = h2_c1_io_pass(&session->io); + } +cleanup: + if (rv != APR_SUCCESS) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, rv, NULL); + } + return rv; +} + +/** + * A streams input state has changed. + */ +static void on_stream_input(void *ctx, h2_stream *stream) +{ + h2_session *session = ctx; + + ap_assert(stream); + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "on_input change")); + update_child_status(session, SERVER_BUSY_READ, "read", stream); + if (stream->id == 0) { + /* input on primary connection available? read */ + h2_c1_read(session); + } + else { + h2_stream_on_input_change(stream); + } +} + +/** + * A streams output state has changed. + */ +static void on_stream_output(void *ctx, h2_stream *stream) +{ + h2_session *session = ctx; + + ap_assert(stream); + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "on_output change")); + if (stream->id != 0) { + update_child_status(session, SERVER_BUSY_WRITE, "write", stream); + h2_stream_on_output_change(stream); + } +} + + +static const char *StateNames[] = { + "INIT", /* H2_SESSION_ST_INIT */ + "DONE", /* H2_SESSION_ST_DONE */ + "IDLE", /* H2_SESSION_ST_IDLE */ + "BUSY", /* H2_SESSION_ST_BUSY */ + "WAIT", /* H2_SESSION_ST_WAIT */ + "CLEANUP", /* H2_SESSION_ST_CLEANUP */ +}; + +const char *h2_session_state_str(h2_session_state state) +{ + if (state >= (sizeof(StateNames)/sizeof(StateNames[0]))) { + return "unknown"; + } + return StateNames[state]; +} + +static void transit(h2_session *session, const char *action, h2_session_state nstate) +{ + int ostate; + + if (session->state != nstate) { + ostate = session->state; + + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03078), session, + "transit [%s] -- %s --> [%s]"), + h2_session_state_str(ostate), action, + h2_session_state_str(nstate)); + + switch (session->state) { + case H2_SESSION_ST_IDLE: + if (!session->remote.emitted_count) { + /* on fresh connections, with async mpm, do not return + * to mpm for a second. This gives the first request a better + * chance to arrive (und connection leaving IDLE state). + * If we return to mpm right away, this connection has the + * same chance of being cleaned up by the mpm as connections + * that already served requests - not fair. */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c1, + H2_SSSN_LOG("", session, "enter idle")); + } + else { + /* normal keepalive setup */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c1, + H2_SSSN_LOG("", session, "enter keepalive")); + } + session->state = nstate; + break; + case H2_SESSION_ST_DONE: + break; + default: + /* nop */ + session->state = nstate; + break; + } + } +} + +static void h2_session_ev_init(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_INIT: + transit(session, "init", H2_SESSION_ST_BUSY); + break; + default: + /* nop */ + break; + } +} + +static void h2_session_ev_input_pending(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_INIT: + case H2_SESSION_ST_IDLE: + case H2_SESSION_ST_WAIT: + transit(session, "input read", H2_SESSION_ST_BUSY); + break; + default: + break; + } +} + +static void h2_session_ev_input_exhausted(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_BUSY: + if (!h2_session_want_send(session)) { + if (session->open_streams == 0) { + transit(session, "input exhausted, no streams", H2_SESSION_ST_IDLE); + } + else { + transit(session, "input exhausted", H2_SESSION_ST_WAIT); + } + } + break; + case H2_SESSION_ST_WAIT: + if (session->open_streams == 0) { + transit(session, "input exhausted, no streams", H2_SESSION_ST_IDLE); + } + break; + default: + break; + } +} + +static void h2_session_ev_local_goaway(h2_session *session, int arg, const char *msg) +{ + cleanup_unprocessed_streams(session); + transit(session, "local goaway", H2_SESSION_ST_DONE); +} + +static void h2_session_ev_remote_goaway(h2_session *session, int arg, const char *msg) +{ + if (!session->remote.shutdown) { + session->remote.error = arg; + session->remote.accepting = 0; + session->remote.shutdown = 1; + cleanup_unprocessed_streams(session); + transit(session, "remote goaway", H2_SESSION_ST_DONE); + } +} + +static void h2_session_ev_conn_error(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_INIT: + case H2_SESSION_ST_DONE: + /* just leave */ + transit(session, "conn error", H2_SESSION_ST_DONE); + break; + + default: + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03401), session, + "conn error -> shutdown")); + h2_session_shutdown(session, arg, msg, 0); + break; + } +} + +static void h2_session_ev_proto_error(h2_session *session, int arg, const char *msg) +{ + if (!session->local.shutdown) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(03402), session, + "proto error -> shutdown")); + h2_session_shutdown(session, arg, msg, 0); + } +} + +static void h2_session_ev_conn_timeout(h2_session *session, int arg, const char *msg) +{ + transit(session, msg, H2_SESSION_ST_DONE); + if (!session->local.shutdown) { + h2_session_shutdown(session, arg, msg, 1); + } +} + +static void h2_session_ev_ngh2_done(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_DONE: + /* nop */ + break; + default: + transit(session, "nghttp2 done", H2_SESSION_ST_DONE); + break; + } +} + +static void h2_session_ev_mpm_stopping(h2_session *session, int arg, const char *msg) +{ + switch (session->state) { + case H2_SESSION_ST_DONE: + /* nop */ + break; + default: + h2_session_shutdown_notice(session); +#if !AP_MODULE_MAGIC_AT_LEAST(20120211, 110) + h2_workers_graceful_shutdown(session->workers); +#endif + break; + } +} + +static void h2_session_ev_pre_close(h2_session *session, int arg, const char *msg) +{ + h2_session_shutdown(session, arg, msg, 1); +} + +static void h2_session_ev_no_more_streams(h2_session *session) +{ + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_SSSN_LOG(APLOGNO(10304), session, "no more streams")); + switch (session->state) { + case H2_SESSION_ST_BUSY: + case H2_SESSION_ST_WAIT: + if (!h2_session_want_send(session)) { + if (session->local.accepting) { + /* We wait for new frames on c1 only. */ + transit(session, "all streams done", H2_SESSION_ST_IDLE); + } + else { + /* We are no longer accepting new streams. + * Time to leave. */ + h2_session_shutdown(session, 0, "done", 0); + transit(session, "c1 done after goaway", H2_SESSION_ST_DONE); + } + } + else { + transit(session, "no more streams", H2_SESSION_ST_WAIT); + } + break; + default: + /* nop */ + break; + } +} + +static void ev_stream_created(h2_session *session, h2_stream *stream) +{ + /* nop */ +} + +static void ev_stream_open(h2_session *session, h2_stream *stream) +{ + if (H2_STREAM_CLIENT_INITIATED(stream->id)) { + ++session->remote.emitted_count; + if (stream->id > session->remote.emitted_max) { + session->remote.emitted_max = stream->id; + session->local.accepted_max = stream->id; + } + } + else { + if (stream->id > session->local.emitted_max) { + ++session->local.emitted_count; + session->remote.emitted_max = stream->id; + } + } + /* Stream state OPEN means we have received all request headers + * and can start processing the stream. */ + h2_iq_append(session->ready_to_process, stream->id); + update_child_status(session, SERVER_BUSY_READ, "schedule", stream); +} + +static void ev_stream_closed(h2_session *session, h2_stream *stream) +{ + apr_bucket *b; + + if (H2_STREAM_CLIENT_INITIATED(stream->id) + && (stream->id > session->local.completed_max)) { + session->local.completed_max = stream->id; + } + /* The stream might have data in the buffers of the main connection. + * We can only free the allocated resources once all had been written. + * Send a special buckets on the connection that gets destroyed when + * all preceding data has been handled. On its destruction, it is safe + * to purge all resources of the stream. */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "adding h2_eos to c1 out")); + b = h2_bucket_eos_create(session->c1->bucket_alloc, stream); + APR_BRIGADE_INSERT_TAIL(session->bbtmp, b); + h2_c1_io_append(&session->io, session->bbtmp); + apr_brigade_cleanup(session->bbtmp); +} + +static void on_stream_state_enter(void *ctx, h2_stream *stream) +{ + h2_session *session = ctx; + + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, 0, session->c1, + H2_STRM_MSG(stream, "entered state")); + switch (stream->state) { + case H2_SS_IDLE: /* stream was created */ + ev_stream_created(session, stream); + break; + case H2_SS_OPEN: /* stream has request headers */ + case H2_SS_RSVD_L: + ev_stream_open(session, stream); + break; + case H2_SS_CLOSED_L: /* stream output was closed, but remote end is not */ + /* If the stream is still being processed, it could still be reading + * its input (theoretically, http request hangling does not normally). + * But when processing is done, we need to cancel the stream as no + * one is consuming the input any longer. + * This happens, for example, on a large POST when the response + * is ready early due to the POST being denied. */ + if (!h2_mplx_c1_stream_is_running(session->mplx, stream)) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, session->c1, + H2_STRM_LOG(APLOGNO(10305), stream, "remote close missing")); + nghttp2_submit_rst_stream(session->ngh2, NGHTTP2_FLAG_NONE, + stream->id, H2_ERR_NO_ERROR); + } + break; + case H2_SS_CLOSED_R: /* stream input was closed */ + break; + case H2_SS_CLOSED: /* stream in+out were closed */ + ev_stream_closed(session, stream); + break; + case H2_SS_CLEANUP: + nghttp2_session_set_stream_user_data(session->ngh2, stream->id, NULL); + h2_mplx_c1_stream_cleanup(session->mplx, stream, &session->open_streams); + ++session->streams_done; + update_child_status(session, SERVER_BUSY_WRITE, "done", stream); + if (session->open_streams == 0) { + h2_session_dispatch_event(session, H2_SESSION_EV_NO_MORE_STREAMS, + 0, "stream done"); + } + break; + default: + break; + } +} + +static void on_stream_event(void *ctx, h2_stream *stream, h2_stream_event_t ev) +{ + h2_session *session = ctx; + switch (ev) { + case H2_SEV_IN_DATA_PENDING: + session->input_flushed = 1; + break; + case H2_SEV_OUT_C1_BLOCK: + h2_iq_append(session->out_c1_blocked, stream->id); + break; + default: + /* NOP */ + break; + } +} + +static void on_stream_state_event(void *ctx, h2_stream *stream, + h2_stream_event_t ev) +{ + h2_session *session = ctx; + switch (ev) { + case H2_SEV_CANCELLED: + if (session->state != H2_SESSION_ST_DONE) { + nghttp2_submit_rst_stream(session->ngh2, NGHTTP2_FLAG_NONE, + stream->id, stream->rst_error); + } + break; + default: + /* NOP */ + break; + } +} + +void h2_session_dispatch_event(h2_session *session, h2_session_event_t ev, + apr_status_t arg, const char *msg) +{ + switch (ev) { + case H2_SESSION_EV_INIT: + h2_session_ev_init(session, arg, msg); + break; + case H2_SESSION_EV_INPUT_PENDING: + h2_session_ev_input_pending(session, arg, msg); + break; + case H2_SESSION_EV_INPUT_EXHAUSTED: + h2_session_ev_input_exhausted(session, arg, msg); + break; + case H2_SESSION_EV_LOCAL_GOAWAY: + h2_session_ev_local_goaway(session, arg, msg); + break; + case H2_SESSION_EV_REMOTE_GOAWAY: + h2_session_ev_remote_goaway(session, arg, msg); + break; + case H2_SESSION_EV_CONN_ERROR: + h2_session_ev_conn_error(session, arg, msg); + break; + case H2_SESSION_EV_PROTO_ERROR: + h2_session_ev_proto_error(session, arg, msg); + break; + case H2_SESSION_EV_CONN_TIMEOUT: + h2_session_ev_conn_timeout(session, arg, msg); + break; + case H2_SESSION_EV_NGH2_DONE: + h2_session_ev_ngh2_done(session, arg, msg); + break; + case H2_SESSION_EV_MPM_STOPPING: + h2_session_ev_mpm_stopping(session, arg, msg); + break; + case H2_SESSION_EV_PRE_CLOSE: + h2_session_ev_pre_close(session, arg, msg); + break; + case H2_SESSION_EV_NO_MORE_STREAMS: + h2_session_ev_no_more_streams(session); + break; + default: + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c1, + H2_SSSN_MSG(session, "unknown event %d"), ev); + break; + } +} + +static void unblock_c1_out(h2_session *session) { + int sid; + + while ((sid = h2_iq_shift(session->out_c1_blocked)) > 0) { + nghttp2_session_resume_data(session->ngh2, sid); + } +} + +apr_status_t h2_session_process(h2_session *session, int async) +{ + apr_status_t status = APR_SUCCESS; + conn_rec *c = session->c1; + int rv, mpm_state, trace = APLOGctrace3(c); + + if (trace) { + ap_log_cerror( APLOG_MARK, APLOG_TRACE3, status, c, + H2_SSSN_MSG(session, "process start, async=%d"), async); + } + + if (H2_SESSION_ST_INIT == session->state) { + if (!h2_protocol_is_acceptable_c1(c, session->r, 1)) { + const char *msg = nghttp2_strerror(NGHTTP2_INADEQUATE_SECURITY); + update_child_status(session, SERVER_BUSY_READ, msg, NULL); + h2_session_shutdown(session, APR_EINVAL, msg, 1); + } + else { + update_child_status(session, SERVER_BUSY_READ, "init", NULL); + status = h2_session_start(session, &rv); + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, c, + H2_SSSN_LOG(APLOGNO(03079), session, + "started on %s:%d"), + session->s->server_hostname, + c->local_addr->port); + if (status != APR_SUCCESS) { + h2_session_dispatch_event(session, + H2_SESSION_EV_CONN_ERROR, status, NULL); + } + else { + h2_session_dispatch_event(session, H2_SESSION_EV_INIT, 0, NULL); + } + } + } + + while (session->state != H2_SESSION_ST_DONE) { + + /* PR65731: we may get a new connection to process while the + * MPM already is stopping. For example due to having reached + * MaxRequestsPerChild limit. + * Since this is supposed to handle things gracefully, we need to: + * a) fully initialize the session before GOAWAYing + * b) give the client the chance to submit at least one request + */ + if (session->state != H2_SESSION_ST_INIT /* no longer intializing */ + && session->local.accepted_max > 0 /* have gotten at least one stream */ + && session->local.accepting /* have not already locally shut down */ + && !ap_mpm_query(AP_MPMQ_MPM_STATE, &mpm_state)) { + if (mpm_state == AP_MPMQ_STOPPING) { + h2_session_dispatch_event(session, H2_SESSION_EV_MPM_STOPPING, 0, NULL); + } + } + + session->status[0] = '\0'; + + if (h2_session_want_send(session)) { + h2_session_send(session); + } + else if (!nghttp2_session_want_read(session->ngh2)) { + h2_session_dispatch_event(session, H2_SESSION_EV_NGH2_DONE, 0, NULL); + } + + if (!h2_iq_empty(session->ready_to_process)) { + h2_mplx_c1_process(session->mplx, session->ready_to_process, + get_stream, stream_pri_cmp, session, + &session->open_streams); + transit(session, "scheduled stream", H2_SESSION_ST_BUSY); + } + + if (session->input_flushed) { + transit(session, "forwarded input", H2_SESSION_ST_BUSY); + session->input_flushed = 0; + } + + if (!h2_iq_empty(session->out_c1_blocked)) { + unblock_c1_out(session); + transit(session, "unblocked output", H2_SESSION_ST_BUSY); + } + + if (session->reprioritize) { + h2_mplx_c1_reprioritize(session->mplx, stream_pri_cmp, session); + session->reprioritize = 0; + } + + if (h2_session_want_send(session)) { + h2_session_send(session); + } + + status = h2_c1_io_assure_flushed(&session->io); + if (APR_SUCCESS != status) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, status, NULL); + } + + switch (session->state) { + case H2_SESSION_ST_INIT: + ap_assert(0); + h2_c1_read(session); + break; + + case H2_SESSION_ST_IDLE: + ap_assert(session->open_streams == 0); + ap_assert(nghttp2_session_want_read(session->ngh2)); + if (!h2_session_want_send(session)) { + /* Give any new incoming request a short grace period to + * arrive while we are still hot and return to the mpm + * connection handling when nothing really happened. */ + h2_c1_read(session); + if (H2_SESSION_ST_IDLE == session->state) { + if (async) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, status, c, + H2_SSSN_LOG(APLOGNO(10306), session, + "returning to mpm c1 monitoring")); + goto leaving; + } + else { + /* Not an async mpm, we must continue waiting + * for client data to arrive until the configured + * server Timeout/KeepAliveTimeout happens */ + apr_time_t timeout = (session->open_streams == 0)? + session->s->keep_alive_timeout : + session->s->timeout; + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, status, c, + H2_SSSN_MSG(session, "polling timeout=%d"), + (int)apr_time_sec(timeout)); + status = h2_mplx_c1_poll(session->mplx, timeout, + on_stream_input, + on_stream_output, session); + if (APR_STATUS_IS_TIMEUP(status)) { + if (session->open_streams == 0) { + h2_session_dispatch_event(session, + H2_SESSION_EV_CONN_TIMEOUT, status, NULL); + break; + } + } + else if (APR_SUCCESS != status) { + h2_session_dispatch_event(session, + H2_SESSION_EV_CONN_ERROR, status, NULL); + break; + } + } + } + } + else { + transit(session, "c1 io pending", H2_SESSION_ST_BUSY); + } + break; + + case H2_SESSION_ST_BUSY: + /* IO happening in and out. Make sure we react to c2 events + * inbetween send and receive. */ + status = h2_mplx_c1_poll(session->mplx, 0, + on_stream_input, on_stream_output, session); + if (APR_SUCCESS != status && !APR_STATUS_IS_TIMEUP(status)) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, status, NULL); + break; + } + h2_c1_read(session); + break; + + case H2_SESSION_ST_WAIT: + status = h2_c1_io_assure_flushed(&session->io); + if (APR_SUCCESS != status) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, status, NULL); + break; + } + if (session->open_streams == 0) { + h2_session_dispatch_event(session, H2_SESSION_EV_NO_MORE_STREAMS, + 0, "streams really done"); + if (session->state != H2_SESSION_ST_WAIT) { + break; + } + } + /* No IO happening and input is exhausted. Make sure we have + * flushed any possibly pending output and then wait with + * the c1 connection timeout for sth to happen in our c1/c2 sockets/pipes */ + ap_log_cerror(APLOG_MARK, APLOG_TRACE2, status, c, + H2_SSSN_MSG(session, "polling timeout=%d, open_streams=%d"), + (int)apr_time_sec(session->s->timeout), session->open_streams); + status = h2_mplx_c1_poll(session->mplx, session->s->timeout, + on_stream_input, on_stream_output, session); + if (APR_STATUS_IS_TIMEUP(status)) { + if (session->open_streams == 0) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_TIMEOUT, status, NULL); + break; + } + } + else if (APR_SUCCESS != status) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, status, NULL); + break; + } + break; + + case H2_SESSION_ST_DONE: + h2_c1_read(session); + break; + + default: + ap_log_cerror(APLOG_MARK, APLOG_ERR, APR_EGENERAL, c, + H2_SSSN_LOG(APLOGNO(03080), session, + "unknown state")); + h2_session_dispatch_event(session, H2_SESSION_EV_PROTO_ERROR, APR_EGENERAL, NULL); + break; + } + } + +leaving: + if (trace) { + ap_log_cerror( APLOG_MARK, APLOG_TRACE3, status, c, + H2_SSSN_MSG(session, "process returns")); + } + + if (session->state == H2_SESSION_ST_DONE) { + if (session->local.error) { + char buffer[128]; + const char *msg; + if (session->local.error_msg) { + msg = session->local.error_msg; + } + else { + msg = apr_strerror(session->local.error, buffer, sizeof(buffer)); + } + update_child_status(session, SERVER_CLOSING, msg, NULL); + } + else { + update_child_status(session, SERVER_CLOSING, "done", NULL); + } + } + else if (APR_STATUS_IS_EOF(status) + || APR_STATUS_IS_ECONNRESET(status) + || APR_STATUS_IS_ECONNABORTED(status)) { + h2_session_dispatch_event(session, H2_SESSION_EV_CONN_ERROR, status, NULL); + update_child_status(session, SERVER_CLOSING, "error", NULL); + } + + return (session->state == H2_SESSION_ST_DONE)? APR_EOF : APR_SUCCESS; +} + +apr_status_t h2_session_pre_close(h2_session *session, int async) +{ + apr_status_t status; + + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, session->c1, + H2_SSSN_MSG(session, "pre_close")); + h2_session_dispatch_event(session, H2_SESSION_EV_PRE_CLOSE, 0, + (session->state == H2_SESSION_ST_IDLE)? "timeout" : NULL); + status = session_cleanup(session, "pre_close"); + if (status == APR_SUCCESS) { + /* no one should hold a reference to this session any longer and + * the h2_conn_ctx_twas removed from the connection. + * Take the pool (and thus all subpools etc. down now, instead of + * during cleanup of main connection pool. */ + apr_pool_destroy(session->pool); + } + return status; +} |