1 /* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements. See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License. You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 * byterange_filter.c --- HTTP byterange filter and friends.
22 #include "apr_strings.h"
23 #include "apr_buckets.h"
25 #include "apr_signal.h"
27 #define APR_WANT_STDIO /* for sscanf */
28 #define APR_WANT_STRFUNC
29 #define APR_WANT_MEMFUNC
33 #include "util_filter.h"
34 #include "ap_config.h"
36 #include "http_config.h"
37 #include "http_core.h"
38 #include "http_protocol.h"
39 #include "http_main.h"
40 #include "http_request.h"
41 #include "http_vhost.h"
42 #include "http_log.h" /* For errors detected in basic auth common
44 #include "apr_date.h" /* For apr_date_parse_http and APR_DATE_BAD */
45 #include "util_charset.h"
46 #include "util_ebcdic.h"
47 #include "util_time.h"
58 static int parse_byterange(char *range, apr_off_t clength,
59 apr_off_t *start, apr_off_t *end)
61 char *dash = strchr(range, '-');
69 if ((dash == range)) {
70 /* In the form "-5" */
71 if (apr_strtoff(&number, dash+1, &errp, 10) || *errp) {
74 *start = clength - number;
79 if (apr_strtoff(&number, range, &errp, 10) || *errp) {
84 if (apr_strtoff(&number, dash, &errp, 10) || *errp) {
98 if (*end >= clength) {
106 return (*start > 0 || *end < clength);
109 static int ap_set_byterange(request_rec *r);
111 typedef struct byterange_ctx {
112 apr_bucket_brigade *bb;
119 * Here we try to be compatible with clients that want multipart/x-byteranges
120 * instead of multipart/byteranges (also see above), as per HTTP/1.1. We
121 * look for the Request-Range header (e.g. Netscape 2 and 3) as an indication
122 * that the browser supports an older protocol. We also check User-Agent
123 * for Microsoft Internet Explorer 3, which needs this as well.
125 static int use_range_x(request_rec *r)
128 return (apr_table_get(r->headers_in, "Request-Range")
129 || ((ua = apr_table_get(r->headers_in, "User-Agent"))
130 && ap_strstr_c(ua, "MSIE 3")));
133 #define BYTERANGE_FMT "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT "/%" APR_OFF_T_FMT
134 #define PARTITION_ERR_FMT "apr_brigade_partition() failed " \
135 "[%" APR_OFF_T_FMT ",%" APR_OFF_T_FMT "]"
137 AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
138 apr_bucket_brigade *bb)
140 #define MIN_LENGTH(len1, len2) ((len1 > len2) ? len2 : len1)
141 request_rec *r = f->r;
142 conn_rec *c = r->connection;
145 apr_bucket_brigade *bsend;
146 apr_off_t range_start;
149 apr_off_t clength = 0;
154 /* Iterate through the brigade until reaching EOS or a bucket with
156 for (e = APR_BRIGADE_FIRST(bb);
157 (e != APR_BRIGADE_SENTINEL(bb) && !APR_BUCKET_IS_EOS(e)
158 && e->length != (apr_size_t)-1);
159 e = APR_BUCKET_NEXT(e)) {
160 clength += e->length;
163 /* Don't attempt to do byte range work if this brigade doesn't
164 * contain an EOS, or if any of the buckets has an unknown length;
165 * this avoids the cases where it is expensive to perform
166 * byteranging (i.e. may require arbitrary amounts of memory). */
167 if (!APR_BUCKET_IS_EOS(e) || clength <= 0) {
168 ap_remove_output_filter(f);
169 return ap_pass_brigade(f->next, bb);
172 num_ranges = ap_set_byterange(r);
174 /* We have nothing to do, get out of the way. */
175 if (num_ranges == 0) {
176 ap_remove_output_filter(f);
177 return ap_pass_brigade(f->next, bb);
180 ctx = apr_pcalloc(r->pool, sizeof(*ctx));
181 ctx->num_ranges = num_ranges;
182 /* create a brigade in case we never call ap_save_brigade() */
183 ctx->bb = apr_brigade_create(r->pool, c->bucket_alloc);
185 if (ctx->num_ranges > 1) {
186 /* Is ap_make_content_type required here? */
187 const char *orig_ct = ap_make_content_type(r, r->content_type);
188 ctx->boundary = apr_psprintf(r->pool, "%" APR_UINT64_T_HEX_FMT "%lx",
189 (apr_uint64_t)r->request_time, (long) getpid());
191 ap_set_content_type(r, apr_pstrcat(r->pool, "multipart",
192 use_range_x(r) ? "/x-" : "/",
193 "byteranges; boundary=",
194 ctx->boundary, NULL));
196 ctx->bound_head = apr_pstrcat(r->pool,
197 CRLF "--", ctx->boundary,
198 CRLF "Content-type: ",
200 CRLF "Content-range: bytes ",
202 ap_xlate_proto_to_ascii(ctx->bound_head, strlen(ctx->bound_head));
205 /* this brigade holds what we will be sending */
206 bsend = apr_brigade_create(r->pool, c->bucket_alloc);
208 while ((current = ap_getword(r->pool, &r->range, ','))
209 && (rv = parse_byterange(current, clength, &range_start,
218 /* These calls to apr_brigage_partition should only fail in
219 * pathological cases, e.g. a file being truncated whilst
221 if ((rv = apr_brigade_partition(bb, range_start, &ec)) != APR_SUCCESS) {
222 ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
223 PARTITION_ERR_FMT, range_start, clength);
226 if ((rv = apr_brigade_partition(bb, range_end+1, &e2)) != APR_SUCCESS) {
227 ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
228 PARTITION_ERR_FMT, range_end+1, clength);
234 /* For single range requests, we must produce Content-Range header.
235 * Otherwise, we need to produce the multipart boundaries.
237 if (ctx->num_ranges == 1) {
238 apr_table_setn(r->headers_out, "Content-Range",
239 apr_psprintf(r->pool, "bytes " BYTERANGE_FMT,
240 range_start, range_end, clength));
245 e = apr_bucket_pool_create(ctx->bound_head, strlen(ctx->bound_head),
246 r->pool, c->bucket_alloc);
247 APR_BRIGADE_INSERT_TAIL(bsend, e);
249 ts = apr_psprintf(r->pool, BYTERANGE_FMT CRLF CRLF,
250 range_start, range_end, clength);
251 ap_xlate_proto_to_ascii(ts, strlen(ts));
252 e = apr_bucket_pool_create(ts, strlen(ts), r->pool,
254 APR_BRIGADE_INSERT_TAIL(bsend, e);
262 if (apr_bucket_copy(ec, &foo) != APR_SUCCESS) {
263 /* As above; this should not fail since the bucket has
264 * a known length, but just to be sure, this takes
265 * care of uncopyable buckets that do somehow manage
266 * to slip through. */
267 /* XXX: check for failure? */
268 apr_bucket_read(ec, &str, &len, APR_BLOCK_READ);
269 apr_bucket_copy(ec, &foo);
271 APR_BRIGADE_INSERT_TAIL(bsend, foo);
272 ec = APR_BUCKET_NEXT(ec);
277 ap_remove_output_filter(f);
279 /* bsend is assumed to be empty if we get here. */
280 e = ap_bucket_error_create(HTTP_RANGE_NOT_SATISFIABLE, NULL,
281 r->pool, c->bucket_alloc);
282 APR_BRIGADE_INSERT_TAIL(bsend, e);
283 e = apr_bucket_eos_create(c->bucket_alloc);
284 APR_BRIGADE_INSERT_TAIL(bsend, e);
285 return ap_pass_brigade(f->next, bsend);
288 if (ctx->num_ranges > 1) {
291 /* add the final boundary */
292 end = apr_pstrcat(r->pool, CRLF "--", ctx->boundary, "--" CRLF, NULL);
293 ap_xlate_proto_to_ascii(end, strlen(end));
294 e = apr_bucket_pool_create(end, strlen(end), r->pool, c->bucket_alloc);
295 APR_BRIGADE_INSERT_TAIL(bsend, e);
298 e = apr_bucket_eos_create(c->bucket_alloc);
299 APR_BRIGADE_INSERT_TAIL(bsend, e);
301 /* we're done with the original content - all of our data is in bsend. */
302 apr_brigade_destroy(bb);
304 /* send our multipart output */
305 return ap_pass_brigade(f->next, bsend);
308 static int ap_set_byterange(request_rec *r)
311 const char *if_range;
316 if (r->assbackwards) {
320 /* Check for Range request-header (HTTP/1.1) or Request-Range for
321 * backwards-compatibility with second-draft Luotonen/Franks
322 * byte-ranges (e.g. Netscape Navigator 2-3).
324 * We support this form, with Request-Range, and (farther down) we
325 * send multipart/x-byteranges instead of multipart/byteranges for
326 * Request-Range based requests to work around a bug in Netscape
327 * Navigator 2-3 and MSIE 3.
330 if (!(range = apr_table_get(r->headers_in, "Range"))) {
331 range = apr_table_get(r->headers_in, "Request-Range");
334 if (!range || strncasecmp(range, "bytes=", 6) || r->status != HTTP_OK) {
338 /* is content already a single range? */
339 if (apr_table_get(r->headers_out, "Content-Range")) {
343 /* is content already a multiple range? */
344 if ((ct = apr_table_get(r->headers_out, "Content-Type"))
345 && (!strncasecmp(ct, "multipart/byteranges", 20)
346 || !strncasecmp(ct, "multipart/x-byteranges", 22))) {
350 /* Check the If-Range header for Etag or Date.
351 * Note that this check will return false (as required) if either
352 * of the two etags are weak.
354 if ((if_range = apr_table_get(r->headers_in, "If-Range"))) {
355 if (if_range[0] == '"') {
356 if (!(match = apr_table_get(r->headers_out, "Etag"))
357 || (strcmp(if_range, match) != 0)) {
361 else if (!(match = apr_table_get(r->headers_out, "Last-Modified"))
362 || (strcmp(if_range, match) != 0)) {
367 if (!ap_strchr_c(range, ',')) {
372 /* a multiple range */
376 r->status = HTTP_PARTIAL_CONTENT;
377 r->range = range + 6;