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Diffstat (limited to 'modules/http2/h2_switch.c')
| -rw-r--r-- | modules/http2/h2_switch.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/modules/http2/h2_switch.c b/modules/http2/h2_switch.c new file mode 100644 index 0000000..a30f27c --- /dev/null +++ b/modules/http2/h2_switch.c @@ -0,0 +1,232 @@ +/* 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 <apr_strings.h> +#include <apr_optional.h> +#include <apr_optional_hooks.h> + +#include <httpd.h> +#include <http_core.h> +#include <http_config.h> +#include <http_connection.h> +#include <http_protocol.h> +#include <http_ssl.h> +#include <http_log.h> + +#include "h2_private.h" +#include "h2.h" + +#include "h2_config.h" +#include "h2_conn_ctx.h" +#include "h2_c1.h" +#include "h2_c2.h" +#include "h2_protocol.h" +#include "h2_switch.h" + +/******************************************************************************* + * Once per lifetime init, retrieve optional functions + */ +apr_status_t h2_switch_init(apr_pool_t *pool, server_rec *s) +{ + (void)pool; + ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, s, "h2_switch init"); + + return APR_SUCCESS; +} + +static int h2_protocol_propose(conn_rec *c, request_rec *r, + server_rec *s, + const apr_array_header_t *offers, + apr_array_header_t *proposals) +{ + int proposed = 0; + int is_tls = ap_ssl_conn_is_ssl(c); + const char **protos = is_tls? h2_protocol_ids_tls : h2_protocol_ids_clear; + + if (!h2_mpm_supported()) { + return DECLINED; + } + + if (strcmp(AP_PROTOCOL_HTTP1, ap_get_protocol(c))) { + /* We do not know how to switch from anything else but http/1.1. + */ + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(03083) + "protocol switch: current proto != http/1.1, declined"); + return DECLINED; + } + + if (!h2_protocol_is_acceptable_c1(c, r, 0)) { + ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(03084) + "protocol propose: connection requirements not met"); + return DECLINED; + } + + if (r) { + /* So far, this indicates an HTTP/1 Upgrade header initiated + * protocol switch. For that, the HTTP2-Settings header needs + * to be present and valid for the connection. + */ + const char *p; + + if (!h2_c1_can_upgrade(r)) { + return DECLINED; + } + + p = apr_table_get(r->headers_in, "HTTP2-Settings"); + if (!p) { + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(03085) + "upgrade without HTTP2-Settings declined"); + return DECLINED; + } + + p = apr_table_get(r->headers_in, "Connection"); + if (!ap_find_token(r->pool, p, "http2-settings")) { + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(03086) + "upgrade without HTTP2-Settings declined"); + return DECLINED; + } + + /* We also allow switching only for requests that have no body. + */ + p = apr_table_get(r->headers_in, "Content-Length"); + if (p && strcmp(p, "0")) { + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(03087) + "upgrade with content-length: %s, declined", p); + return DECLINED; + } + } + + while (*protos) { + /* Add all protocols we know (tls or clear) and that + * are part of the offerings (if there have been any). + */ + if (!offers || ap_array_str_contains(offers, *protos)) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, c, + "proposing protocol '%s'", *protos); + APR_ARRAY_PUSH(proposals, const char*) = *protos; + proposed = 1; + } + ++protos; + } + return proposed? DECLINED : OK; +} + +#if AP_HAS_RESPONSE_BUCKETS +static void remove_output_filters_below(ap_filter_t *f, ap_filter_type ftype) +{ + ap_filter_t *fnext; + + while (f && f->frec->ftype < ftype) { + fnext = f->next; + ap_remove_output_filter(f); + f = fnext; + } +} + +static void remove_input_filters_below(ap_filter_t *f, ap_filter_type ftype) +{ + ap_filter_t *fnext; + + while (f && f->frec->ftype < ftype) { + fnext = f->next; + ap_remove_input_filter(f); + f = fnext; + } +} +#endif + +static int h2_protocol_switch(conn_rec *c, request_rec *r, server_rec *s, + const char *protocol) +{ + int found = 0; + const char **protos = ap_ssl_conn_is_ssl(c)? h2_protocol_ids_tls : h2_protocol_ids_clear; + const char **p = protos; + + (void)s; + if (!h2_mpm_supported()) { + return DECLINED; + } + + while (*p) { + if (!strcmp(*p, protocol)) { + found = 1; + break; + } + p++; + } + + if (found) { + ap_log_cerror(APLOG_MARK, APLOG_TRACE1, 0, c, + "switching protocol to '%s'", protocol); + h2_conn_ctx_create_for_c1(c, s, protocol); + + if (r != NULL) { + apr_status_t status; +#if AP_HAS_RESPONSE_BUCKETS + /* Switching in the middle of a request means that + * we have to send out the response to this one in h2 + * format. So we need to take over the connection + * and remove all old filters with type up to the + * CONNEDCTION/NETWORK ones. + */ + remove_input_filters_below(r->input_filters, AP_FTYPE_CONNECTION); + remove_output_filters_below(r->output_filters, AP_FTYPE_CONNECTION); +#else + /* Switching in the middle of a request means that + * we have to send out the response to this one in h2 + * format. So we need to take over the connection + * right away. + */ + ap_remove_input_filter_byhandle(r->input_filters, "http_in"); + ap_remove_output_filter_byhandle(r->output_filters, "HTTP_HEADER"); +#endif + /* Ok, start an h2_conn on this one. */ + status = h2_c1_setup(c, r, s); + + if (status != APR_SUCCESS) { + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, status, r, APLOGNO(03088) + "session setup"); + h2_conn_ctx_detach(c); + return !OK; + } + + h2_c1_run(c); + } + return OK; + } + + return DECLINED; +} + +static const char *h2_protocol_get(const conn_rec *c) +{ + h2_conn_ctx_t *ctx; + + if (c->master) { + c = c->master; + } + ctx = h2_conn_ctx_get(c); + return ctx? ctx->protocol : NULL; +} + +void h2_switch_register_hooks(void) +{ + ap_hook_protocol_propose(h2_protocol_propose, NULL, NULL, APR_HOOK_MIDDLE); + ap_hook_protocol_switch(h2_protocol_switch, NULL, NULL, APR_HOOK_MIDDLE); + ap_hook_protocol_get(h2_protocol_get, NULL, NULL, APR_HOOK_MIDDLE); +} |