| /* 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. |
| */ |
| |
| /* |
| * chunk_filter.c --- HTTP/1.1 chunked transfer encoding filter. |
| */ |
| |
| #include "apr_strings.h" |
| #include "apr_lib.h" |
| #include "apr_thread_proc.h" /* for RLIMIT stuff */ |
| |
| #define APR_WANT_STRFUNC |
| #include "apr_want.h" |
| |
| #include "httpd.h" |
| #include "http_config.h" |
| #include "http_connection.h" |
| #include "http_core.h" |
| #include "http_log.h" |
| #include "http_protocol.h" /* For index_of_response(). Grump. */ |
| #include "http_request.h" |
| |
| #include "util_filter.h" |
| #include "util_ebcdic.h" |
| #include "ap_mpm.h" |
| #include "scoreboard.h" |
| |
| #include "mod_core.h" |
| |
| |
| APLOG_USE_MODULE(http); |
| |
| |
| typedef struct chunk_out_ctx { |
| int bad_gateway_seen; |
| apr_table_t *trailers; |
| } chunk_out_ctx; |
| |
| |
| apr_status_t ap_http_chunk_filter(ap_filter_t *f, apr_bucket_brigade *b) |
| { |
| conn_rec *c = f->r->connection; |
| chunk_out_ctx *ctx = f->ctx; |
| apr_bucket_brigade *more, *tmp; |
| apr_bucket *e; |
| apr_status_t rv; |
| |
| if (!ctx) { |
| ctx = f->ctx = apr_pcalloc(f->r->pool, sizeof(*ctx)); |
| } |
| |
| for (more = tmp = NULL; b; b = more, more = NULL) { |
| apr_off_t bytes = 0; |
| apr_bucket *eos = NULL; /* EOS bucket, or FLUSH preceding EOS */ |
| apr_bucket *flush = NULL; |
| /* XXX: chunk_hdr must remain at this scope since it is used in a |
| * transient bucket. |
| */ |
| char chunk_hdr[20]; /* enough space for the snprintf below */ |
| |
| |
| for (e = APR_BRIGADE_FIRST(b); |
| e != APR_BRIGADE_SENTINEL(b); |
| e = APR_BUCKET_NEXT(e)) |
| { |
| if (APR_BUCKET_IS_METADATA(e)) { |
| if (APR_BUCKET_IS_EOS(e)) { |
| /* there shouldn't be anything after the eos */ |
| ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, f->r, |
| "ap_http_chunk_filter eos seen, removing filter"); |
| ap_remove_output_filter(f); |
| eos = e; |
| break; |
| } |
| if (AP_BUCKET_IS_ERROR(e) && |
| (((ap_bucket_error *)(e->data))->status == HTTP_BAD_GATEWAY || |
| ((ap_bucket_error *)(e->data))->status == HTTP_GATEWAY_TIME_OUT)) { |
| /* |
| * We had a broken backend. Memorize this in the filter |
| * context. |
| */ |
| ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, f->r, |
| "ap_http_chunk_filter bad gateway error, suppressing end chunk"); |
| ctx->bad_gateway_seen = 1; |
| continue; |
| } |
| if (APR_BUCKET_IS_FLUSH(e)) { |
| flush = e; |
| |
| /* Special case to catch common brigade ending of |
| * [FLUSH] [EOS] - insert the last_chunk before |
| * the FLUSH rather than between the FLUSH and the |
| * EOS. */ |
| if (e != APR_BRIGADE_LAST(b)) { |
| if (APR_BUCKET_IS_EOS(APR_BUCKET_NEXT(e))) { |
| eos = e; |
| /* anything after EOS is dropped, no need |
| * to split. */ |
| } |
| else { |
| more = apr_brigade_split_ex(b, APR_BUCKET_NEXT(e), tmp); |
| } |
| } |
| break; |
| } |
| if (AP_BUCKET_IS_HEADERS(e)) { |
| ap_bucket_headers *hdrs = e->data; |
| if (!apr_is_empty_table(hdrs->headers)) { |
| if (!ctx->trailers) { |
| ctx->trailers = apr_table_make(f->r->pool, 5); |
| } |
| apr_table_overlap(ctx->trailers, hdrs->headers, APR_OVERLAP_TABLES_MERGE); |
| } |
| } |
| } |
| else if (e->length == (apr_size_t)-1) { |
| /* unknown amount of data (e.g. a pipe) */ |
| const char *data; |
| apr_size_t len; |
| |
| rv = apr_bucket_read(e, &data, &len, APR_BLOCK_READ); |
| if (rv != APR_SUCCESS) { |
| return rv; |
| } |
| if (len > 0) { |
| /* |
| * There may be a new next bucket representing the |
| * rest of the data stream on which a read() may |
| * block so we pass down what we have so far. |
| */ |
| bytes += len; |
| more = apr_brigade_split_ex(b, APR_BUCKET_NEXT(e), tmp); |
| break; |
| } |
| else { |
| /* If there was nothing in this bucket then we can |
| * safely move on to the next one without pausing |
| * to pass down what we have counted up so far. |
| */ |
| continue; |
| } |
| } |
| else { |
| bytes += e->length; |
| } |
| } |
| |
| /* |
| * XXX: if there aren't very many bytes at this point it may |
| * be a good idea to set them aside and return for more, |
| * unless we haven't finished counting this brigade yet. |
| */ |
| /* if there are content bytes, then wrap them in a chunk */ |
| if (bytes > 0) { |
| apr_size_t hdr_len; |
| /* |
| * Insert the chunk header, specifying the number of bytes in |
| * the chunk. |
| */ |
| ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, f->r, |
| "ap_http_chunk_filter sending chunk of %" |
| APR_UINT64_T_HEX_FMT " bytes", (apr_uint64_t)bytes); |
| hdr_len = apr_snprintf(chunk_hdr, sizeof(chunk_hdr), |
| "%" APR_UINT64_T_HEX_FMT CRLF, (apr_uint64_t)bytes); |
| ap_xlate_proto_to_ascii(chunk_hdr, hdr_len); |
| e = apr_bucket_transient_create(chunk_hdr, hdr_len, |
| c->bucket_alloc); |
| APR_BRIGADE_INSERT_HEAD(b, e); |
| |
| /* |
| * Insert the end-of-chunk CRLF before an EOS or |
| * FLUSH bucket, or appended to the brigade |
| */ |
| e = apr_bucket_immortal_create(CRLF_ASCII, 2, c->bucket_alloc); |
| if (flush != NULL) { |
| APR_BUCKET_INSERT_BEFORE(flush, e); |
| } |
| else if (eos != NULL) { |
| APR_BUCKET_INSERT_BEFORE(eos, e); |
| } |
| else { |
| APR_BRIGADE_INSERT_TAIL(b, e); |
| } |
| } |
| |
| /* RFC 2616, Section 3.6.1 |
| * |
| * If there is an EOS bucket, then prefix it with: |
| * 1) the last-chunk marker ("0" CRLF) |
| * 2) the trailer |
| * 3) the end-of-chunked body CRLF |
| * |
| * We only do this if we have not seen an error bucket with |
| * status HTTP_BAD_GATEWAY. We have memorized an |
| * error bucket that we had seen in the filter context. |
| * The error bucket with status HTTP_BAD_GATEWAY indicates that the |
| * connection to the backend (mod_proxy) broke in the middle of the |
| * response. In order to signal the client that something went wrong |
| * we do not create the last-chunk marker and set c->keepalive to |
| * AP_CONN_CLOSE in the core output filter. |
| * |
| * XXX: it would be nice to combine this with the end-of-chunk |
| * marker above, but this is a bit more straight-forward for |
| * now. |
| */ |
| if (eos && !ctx->bad_gateway_seen) { |
| ap_h1_add_end_chunk(b, eos, f->r, ctx->trailers); |
| } |
| |
| /* pass the brigade to the next filter. */ |
| rv = ap_pass_brigade(f->next, b); |
| apr_brigade_cleanup(b); |
| if (rv != APR_SUCCESS || eos != NULL) { |
| return rv; |
| } |
| tmp = b; |
| } |
| return APR_SUCCESS; |
| } |
