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diff --git a/rubbos/app/httpd-2.0.64/modules/http/http_protocol.c b/rubbos/app/httpd-2.0.64/modules/http/http_protocol.c
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@@ -0,0 +1,3212 @@
+/* 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.
+ */
+
+/*
+ * http_protocol.c --- routines which directly communicate with the client.
+ *
+ * Code originally by Rob McCool; much redone by Robert S. Thau
+ * and the Apache Software Foundation.
+ */
+
+#include "apr.h"
+#include "apr_strings.h"
+#include "apr_buckets.h"
+#include "apr_lib.h"
+#include "apr_signal.h"
+
+#define APR_WANT_STDIO /* for sscanf */
+#define APR_WANT_STRFUNC
+#define APR_WANT_MEMFUNC
+#include "apr_want.h"
+
+#define CORE_PRIVATE
+#include "util_filter.h"
+#include "ap_config.h"
+#include "httpd.h"
+#include "http_config.h"
+#include "http_core.h"
+#include "http_protocol.h"
+#include "http_main.h"
+#include "http_request.h"
+#include "http_vhost.h"
+#include "http_log.h" /* For errors detected in basic auth common
+ * support code... */
+#include "apr_date.h" /* For apr_date_parse_http and APR_DATE_BAD */
+#include "util_charset.h"
+#include "util_ebcdic.h"
+#include "util_time.h"
+
+#include "mod_core.h"
+
+#if APR_HAVE_STDARG_H
+#include <stdarg.h>
+#endif
+#if APR_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+/* New Apache routine to map status codes into array indicies
+ * e.g. 100 -> 0, 101 -> 1, 200 -> 2 ...
+ * The number of status lines must equal the value of RESPONSE_CODES (httpd.h)
+ * and must be listed in order.
+ */
+
+#ifdef UTS21
+/* The second const triggers an assembler bug on UTS 2.1.
+ * Another workaround is to move some code out of this file into another,
+ * but this is easier. Dave Dykstra, 3/31/99
+ */
+static const char * status_lines[RESPONSE_CODES] =
+#else
+static const char * const status_lines[RESPONSE_CODES] =
+#endif
+{
+ "100 Continue",
+ "101 Switching Protocols",
+ "102 Processing",
+#define LEVEL_200 3
+ "200 OK",
+ "201 Created",
+ "202 Accepted",
+ "203 Non-Authoritative Information",
+ "204 No Content",
+ "205 Reset Content",
+ "206 Partial Content",
+ "207 Multi-Status",
+#define LEVEL_300 11
+ "300 Multiple Choices",
+ "301 Moved Permanently",
+ "302 Found",
+ "303 See Other",
+ "304 Not Modified",
+ "305 Use Proxy",
+ "306 unused",
+ "307 Temporary Redirect",
+#define LEVEL_400 19
+ "400 Bad Request",
+ "401 Authorization Required",
+ "402 Payment Required",
+ "403 Forbidden",
+ "404 Not Found",
+ "405 Method Not Allowed",
+ "406 Not Acceptable",
+ "407 Proxy Authentication Required",
+ "408 Request Time-out",
+ "409 Conflict",
+ "410 Gone",
+ "411 Length Required",
+ "412 Precondition Failed",
+ "413 Request Entity Too Large",
+ "414 Request-URI Too Large",
+ "415 Unsupported Media Type",
+ "416 Requested Range Not Satisfiable",
+ "417 Expectation Failed",
+ "418 unused",
+ "419 unused",
+ "420 unused",
+ "421 unused",
+ "422 Unprocessable Entity",
+ "423 Locked",
+ "424 Failed Dependency",
+ /* This is a hack, but it is required for ap_index_of_response
+ * to work with 426.
+ */
+ "425 No code",
+ "426 Upgrade Required",
+#define LEVEL_500 46
+ "500 Internal Server Error",
+ "501 Method Not Implemented",
+ "502 Bad Gateway",
+ "503 Service Temporarily Unavailable",
+ "504 Gateway Time-out",
+ "505 HTTP Version Not Supported",
+ "506 Variant Also Negotiates",
+ "507 Insufficient Storage",
+ "508 unused",
+ "509 unused",
+ "510 Not Extended"
+};
+
+APR_HOOK_STRUCT(
+ APR_HOOK_LINK(insert_error_filter)
+)
+
+AP_IMPLEMENT_HOOK_VOID(insert_error_filter, (request_rec *r), (r))
+
+/* The index of the first bit field that is used to index into a limit
+ * bitmask. M_INVALID + 1 to METHOD_NUMBER_LAST.
+ */
+#define METHOD_NUMBER_FIRST (M_INVALID + 1)
+
+/* The max method number. Method numbers are used to shift bitmasks,
+ * so this cannot exceed 63, and all bits high is equal to -1, which is a
+ * special flag, so the last bit used has index 62.
+ */
+#define METHOD_NUMBER_LAST 62
+
+
+AP_DECLARE(int) ap_set_keepalive(request_rec *r)
+{
+ int ka_sent = 0;
+ int wimpy = ap_find_token(r->pool,
+ apr_table_get(r->headers_out, "Connection"),
+ "close");
+ const char *conn = apr_table_get(r->headers_in, "Connection");
+
+ /* The following convoluted conditional determines whether or not
+ * the current connection should remain persistent after this response
+ * (a.k.a. HTTP Keep-Alive) and whether or not the output message
+ * body should use the HTTP/1.1 chunked transfer-coding. In English,
+ *
+ * IF we have not marked this connection as errored;
+ * and the response body has a defined length due to the status code
+ * being 304 or 204, the request method being HEAD, already
+ * having defined Content-Length or Transfer-Encoding: chunked, or
+ * the request version being HTTP/1.1 and thus capable of being set
+ * as chunked [we know the (r->chunked = 1) side-effect is ugly];
+ * and the server configuration enables keep-alive;
+ * and the server configuration has a reasonable inter-request timeout;
+ * and there is no maximum # requests or the max hasn't been reached;
+ * and the response status does not require a close;
+ * and the response generator has not already indicated close;
+ * and the client did not request non-persistence (Connection: close);
+ * and we haven't been configured to ignore the buggy twit
+ * or they're a buggy twit coming through a HTTP/1.1 proxy
+ * and the client is requesting an HTTP/1.0-style keep-alive
+ * or the client claims to be HTTP/1.1 compliant (perhaps a proxy);
+ * THEN we can be persistent, which requires more headers be output.
+ *
+ * Note that the condition evaluation order is extremely important.
+ */
+ if ((r->connection->keepalive != AP_CONN_CLOSE)
+ && ((r->status == HTTP_NOT_MODIFIED)
+ || (r->status == HTTP_NO_CONTENT)
+ || r->header_only
+ || apr_table_get(r->headers_out, "Content-Length")
+ || ap_find_last_token(r->pool,
+ apr_table_get(r->headers_out,
+ "Transfer-Encoding"),
+ "chunked")
+ || ((r->proto_num >= HTTP_VERSION(1,1))
+ && (r->chunked = 1))) /* THIS CODE IS CORRECT, see above. */
+ && r->server->keep_alive
+ && (r->server->keep_alive_timeout > 0)
+ && ((r->server->keep_alive_max == 0)
+ || (r->server->keep_alive_max > r->connection->keepalives))
+ && !ap_status_drops_connection(r->status)
+ && !wimpy
+ && !ap_find_token(r->pool, conn, "close")
+ && (!apr_table_get(r->subprocess_env, "nokeepalive")
+ || apr_table_get(r->headers_in, "Via"))
+ && ((ka_sent = ap_find_token(r->pool, conn, "keep-alive"))
+ || (r->proto_num >= HTTP_VERSION(1,1)))) {
+ int left = r->server->keep_alive_max - r->connection->keepalives;
+
+ r->connection->keepalive = AP_CONN_KEEPALIVE;
+ r->connection->keepalives++;
+
+ /* If they sent a Keep-Alive token, send one back */
+ if (ka_sent) {
+ if (r->server->keep_alive_max) {
+ apr_table_setn(r->headers_out, "Keep-Alive",
+ apr_psprintf(r->pool, "timeout=%d, max=%d",
+ (int)apr_time_sec(r->server->keep_alive_timeout),
+ left));
+ }
+ else {
+ apr_table_setn(r->headers_out, "Keep-Alive",
+ apr_psprintf(r->pool, "timeout=%d",
+ (int)apr_time_sec(r->server->keep_alive_timeout)));
+ }
+ apr_table_mergen(r->headers_out, "Connection", "Keep-Alive");
+ }
+
+ return 1;
+ }
+
+ /* Otherwise, we need to indicate that we will be closing this
+ * connection immediately after the current response.
+ *
+ * We only really need to send "close" to HTTP/1.1 clients, but we
+ * always send it anyway, because a broken proxy may identify itself
+ * as HTTP/1.0, but pass our request along with our HTTP/1.1 tag
+ * to a HTTP/1.1 client. Better safe than sorry.
+ */
+ if (!wimpy) {
+ apr_table_mergen(r->headers_out, "Connection", "close");
+ }
+
+ r->connection->keepalive = AP_CONN_CLOSE;
+
+ return 0;
+}
+
+AP_DECLARE(int) ap_meets_conditions(request_rec *r)
+{
+ const char *etag;
+ const char *if_match, *if_modified_since, *if_unmodified, *if_nonematch;
+ apr_time_t tmp_time;
+ apr_int64_t mtime;
+
+ /* Check for conditional requests --- note that we only want to do
+ * this if we are successful so far and we are not processing a
+ * subrequest or an ErrorDocument.
+ *
+ * The order of the checks is important, since ETag checks are supposed
+ * to be more accurate than checks relative to the modification time.
+ * However, not all documents are guaranteed to *have* ETags, and some
+ * might have Last-Modified values w/o ETags, so this gets a little
+ * complicated.
+ */
+
+ if (!ap_is_HTTP_SUCCESS(r->status) || r->no_local_copy) {
+ return OK;
+ }
+
+ etag = apr_table_get(r->headers_out, "ETag");
+
+ /* All of our comparisons must be in seconds, because that's the
+ * highest time resolution the HTTP specification allows.
+ */
+ /* XXX: we should define a "time unset" constant */
+ tmp_time = ((r->mtime != 0) ? r->mtime : apr_time_now());
+ mtime = apr_time_sec(tmp_time);
+
+ /* If an If-Match request-header field was given
+ * AND the field value is not "*" (meaning match anything)
+ * AND if our strong ETag does not match any entity tag in that field,
+ * respond with a status of 412 (Precondition Failed).
+ */
+ if ((if_match = apr_table_get(r->headers_in, "If-Match")) != NULL) {
+ if (if_match[0] != '*'
+ && (etag == NULL || etag[0] == 'W'
+ || !ap_find_list_item(r->pool, if_match, etag))) {
+ return HTTP_PRECONDITION_FAILED;
+ }
+ }
+ else {
+ /* Else if a valid If-Unmodified-Since request-header field was given
+ * AND the requested resource has been modified since the time
+ * specified in this field, then the server MUST
+ * respond with a status of 412 (Precondition Failed).
+ */
+ if_unmodified = apr_table_get(r->headers_in, "If-Unmodified-Since");
+ if (if_unmodified != NULL) {
+ apr_time_t ius = apr_date_parse_http(if_unmodified);
+
+ if ((ius != APR_DATE_BAD) && (mtime > apr_time_sec(ius))) {
+ return HTTP_PRECONDITION_FAILED;
+ }
+ }
+ }
+
+ /* If an If-None-Match request-header field was given
+ * AND the field value is "*" (meaning match anything)
+ * OR our ETag matches any of the entity tags in that field, fail.
+ *
+ * If the request method was GET or HEAD, failure means the server
+ * SHOULD respond with a 304 (Not Modified) response.
+ * For all other request methods, failure means the server MUST
+ * respond with a status of 412 (Precondition Failed).
+ *
+ * GET or HEAD allow weak etag comparison, all other methods require
+ * strong comparison. We can only use weak if it's not a range request.
+ */
+ if_nonematch = apr_table_get(r->headers_in, "If-None-Match");
+ if (if_nonematch != NULL) {
+ if (r->method_number == M_GET) {
+ if (if_nonematch[0] == '*') {
+ return HTTP_NOT_MODIFIED;
+ }
+ if (etag != NULL) {
+ if (apr_table_get(r->headers_in, "Range")) {
+ if (etag[0] != 'W'
+ && ap_find_list_item(r->pool, if_nonematch, etag)) {
+ return HTTP_NOT_MODIFIED;
+ }
+ }
+ else if (ap_strstr_c(if_nonematch, etag)) {
+ return HTTP_NOT_MODIFIED;
+ }
+ }
+ }
+ else if (if_nonematch[0] == '*'
+ || (etag != NULL
+ && ap_find_list_item(r->pool, if_nonematch, etag))) {
+ return HTTP_PRECONDITION_FAILED;
+ }
+ }
+ /* Else if a valid If-Modified-Since request-header field was given
+ * AND it is a GET or HEAD request
+ * AND the requested resource has not been modified since the time
+ * specified in this field, then the server MUST
+ * respond with a status of 304 (Not Modified).
+ * A date later than the server's current request time is invalid.
+ */
+ else if ((r->method_number == M_GET)
+ && ((if_modified_since =
+ apr_table_get(r->headers_in,
+ "If-Modified-Since")) != NULL)) {
+ apr_time_t ims_time;
+ apr_int64_t ims, reqtime;
+
+ ims_time = apr_date_parse_http(if_modified_since);
+ ims = apr_time_sec(ims_time);
+ reqtime = apr_time_sec(r->request_time);
+
+ if ((ims >= mtime) && (ims <= reqtime)) {
+ return HTTP_NOT_MODIFIED;
+ }
+ }
+ return OK;
+}
+
+/**
+ * Singleton registry of additional methods. This maps new method names
+ * such as "MYGET" to methnums, which are int offsets into bitmasks.
+ *
+ * This follows the same technique as standard M_GET, M_POST, etc. These
+ * are dynamically assigned when modules are loaded and <Limit GET MYGET>
+ * directives are processed.
+ */
+static apr_hash_t *methods_registry = NULL;
+static int cur_method_number = METHOD_NUMBER_FIRST;
+
+/* internal function to register one method/number pair */
+static void register_one_method(apr_pool_t *p, const char *methname,
+ int methnum)
+{
+ int *pnum = apr_palloc(p, sizeof(*pnum));
+
+ *pnum = methnum;
+ apr_hash_set(methods_registry, methname, APR_HASH_KEY_STRING, pnum);
+}
+
+/* This internal function is used to clear the method registry
+ * and reset the cur_method_number counter.
+ */
+static apr_status_t ap_method_registry_destroy(void *notused)
+{
+ methods_registry = NULL;
+ cur_method_number = METHOD_NUMBER_FIRST;
+ return APR_SUCCESS;
+}
+
+AP_DECLARE(void) ap_method_registry_init(apr_pool_t *p)
+{
+ methods_registry = apr_hash_make(p);
+ apr_pool_cleanup_register(p, NULL,
+ ap_method_registry_destroy,
+ apr_pool_cleanup_null);
+
+ /* put all the standard methods into the registry hash to ease the
+ mapping operations between name and number */
+ register_one_method(p, "GET", M_GET);
+ register_one_method(p, "PUT", M_PUT);
+ register_one_method(p, "POST", M_POST);
+ register_one_method(p, "DELETE", M_DELETE);
+ register_one_method(p, "CONNECT", M_CONNECT);
+ register_one_method(p, "OPTIONS", M_OPTIONS);
+ register_one_method(p, "TRACE", M_TRACE);
+ register_one_method(p, "PATCH", M_PATCH);
+ register_one_method(p, "PROPFIND", M_PROPFIND);
+ register_one_method(p, "PROPPATCH", M_PROPPATCH);
+ register_one_method(p, "MKCOL", M_MKCOL);
+ register_one_method(p, "COPY", M_COPY);
+ register_one_method(p, "MOVE", M_MOVE);
+ register_one_method(p, "LOCK", M_LOCK);
+ register_one_method(p, "UNLOCK", M_UNLOCK);
+ register_one_method(p, "VERSION-CONTROL", M_VERSION_CONTROL);
+ register_one_method(p, "CHECKOUT", M_CHECKOUT);
+ register_one_method(p, "UNCHECKOUT", M_UNCHECKOUT);
+ register_one_method(p, "CHECKIN", M_CHECKIN);
+ register_one_method(p, "UPDATE", M_UPDATE);
+ register_one_method(p, "LABEL", M_LABEL);
+ register_one_method(p, "REPORT", M_REPORT);
+ register_one_method(p, "MKWORKSPACE", M_MKWORKSPACE);
+ register_one_method(p, "MKACTIVITY", M_MKACTIVITY);
+ register_one_method(p, "BASELINE-CONTROL", M_BASELINE_CONTROL);
+ register_one_method(p, "MERGE", M_MERGE);
+}
+
+AP_DECLARE(int) ap_method_register(apr_pool_t *p, const char *methname)
+{
+ int *methnum;
+
+ if (methods_registry == NULL) {
+ ap_method_registry_init(p);
+ }
+
+ if (methname == NULL) {
+ return M_INVALID;
+ }
+
+ /* Check if the method was previously registered. If it was
+ * return the associated method number.
+ */
+ methnum = (int *)apr_hash_get(methods_registry, methname,
+ APR_HASH_KEY_STRING);
+ if (methnum != NULL)
+ return *methnum;
+
+ if (cur_method_number > METHOD_NUMBER_LAST) {
+ /* The method registry has run out of dynamically
+ * assignable method numbers. Log this and return M_INVALID.
+ */
+ ap_log_perror(APLOG_MARK, APLOG_ERR, 0, p,
+ "Maximum new request methods %d reached while "
+ "registering method %s.",
+ METHOD_NUMBER_LAST, methname);
+ return M_INVALID;
+ }
+
+ register_one_method(p, methname, cur_method_number);
+ return cur_method_number++;
+}
+
+#define UNKNOWN_METHOD (-1)
+
+static int lookup_builtin_method(const char *method, apr_size_t len)
+{
+ /* Note: the following code was generated by the "shilka" tool from
+ the "cocom" parsing/compilation toolkit. It is an optimized lookup
+ based on analysis of the input keywords. Postprocessing was done
+ on the shilka output, but the basic structure and analysis is
+ from there. Should new HTTP methods be added, then manual insertion
+ into this code is fine, or simply re-running the shilka tool on
+ the appropriate input. */
+
+ /* Note: it is also quite reasonable to just use our method_registry,
+ but I'm assuming (probably incorrectly) we want more speed here
+ (based on the optimizations the previous code was doing). */
+
+ switch (len)
+ {
+ case 3:
+ switch (method[0])
+ {
+ case 'P':
+ return (method[1] == 'U'
+ && method[2] == 'T'
+ ? M_PUT : UNKNOWN_METHOD);
+ case 'G':
+ return (method[1] == 'E'
+ && method[2] == 'T'
+ ? M_GET : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 4:
+ switch (method[0])
+ {
+ case 'H':
+ return (method[1] == 'E'
+ && method[2] == 'A'
+ && method[3] == 'D'
+ ? M_GET : UNKNOWN_METHOD);
+ case 'P':
+ return (method[1] == 'O'
+ && method[2] == 'S'
+ && method[3] == 'T'
+ ? M_POST : UNKNOWN_METHOD);
+ case 'M':
+ return (method[1] == 'O'
+ && method[2] == 'V'
+ && method[3] == 'E'
+ ? M_MOVE : UNKNOWN_METHOD);
+ case 'L':
+ return (method[1] == 'O'
+ && method[2] == 'C'
+ && method[3] == 'K'
+ ? M_LOCK : UNKNOWN_METHOD);
+ case 'C':
+ return (method[1] == 'O'
+ && method[2] == 'P'
+ && method[3] == 'Y'
+ ? M_COPY : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 5:
+ switch (method[2])
+ {
+ case 'T':
+ return (memcmp(method, "PATCH", 5) == 0
+ ? M_PATCH : UNKNOWN_METHOD);
+ case 'R':
+ return (memcmp(method, "MERGE", 5) == 0
+ ? M_MERGE : UNKNOWN_METHOD);
+ case 'C':
+ return (memcmp(method, "MKCOL", 5) == 0
+ ? M_MKCOL : UNKNOWN_METHOD);
+ case 'B':
+ return (memcmp(method, "LABEL", 5) == 0
+ ? M_LABEL : UNKNOWN_METHOD);
+ case 'A':
+ return (memcmp(method, "TRACE", 5) == 0
+ ? M_TRACE : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 6:
+ switch (method[0])
+ {
+ case 'U':
+ switch (method[5])
+ {
+ case 'K':
+ return (memcmp(method, "UNLOCK", 6) == 0
+ ? M_UNLOCK : UNKNOWN_METHOD);
+ case 'E':
+ return (memcmp(method, "UPDATE", 6) == 0
+ ? M_UPDATE : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+ case 'R':
+ return (memcmp(method, "REPORT", 6) == 0
+ ? M_REPORT : UNKNOWN_METHOD);
+ case 'D':
+ return (memcmp(method, "DELETE", 6) == 0
+ ? M_DELETE : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 7:
+ switch (method[1])
+ {
+ case 'P':
+ return (memcmp(method, "OPTIONS", 7) == 0
+ ? M_OPTIONS : UNKNOWN_METHOD);
+ case 'O':
+ return (memcmp(method, "CONNECT", 7) == 0
+ ? M_CONNECT : UNKNOWN_METHOD);
+ case 'H':
+ return (memcmp(method, "CHECKIN", 7) == 0
+ ? M_CHECKIN : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 8:
+ switch (method[0])
+ {
+ case 'P':
+ return (memcmp(method, "PROPFIND", 8) == 0
+ ? M_PROPFIND : UNKNOWN_METHOD);
+ case 'C':
+ return (memcmp(method, "CHECKOUT", 8) == 0
+ ? M_CHECKOUT : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 9:
+ return (memcmp(method, "PROPPATCH", 9) == 0
+ ? M_PROPPATCH : UNKNOWN_METHOD);
+
+ case 10:
+ switch (method[0])
+ {
+ case 'U':
+ return (memcmp(method, "UNCHECKOUT", 10) == 0
+ ? M_UNCHECKOUT : UNKNOWN_METHOD);
+ case 'M':
+ return (memcmp(method, "MKACTIVITY", 10) == 0
+ ? M_MKACTIVITY : UNKNOWN_METHOD);
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ case 11:
+ return (memcmp(method, "MKWORKSPACE", 11) == 0
+ ? M_MKWORKSPACE : UNKNOWN_METHOD);
+
+ case 15:
+ return (memcmp(method, "VERSION-CONTROL", 15) == 0
+ ? M_VERSION_CONTROL : UNKNOWN_METHOD);
+
+ case 16:
+ return (memcmp(method, "BASELINE-CONTROL", 16) == 0
+ ? M_BASELINE_CONTROL : UNKNOWN_METHOD);
+
+ default:
+ return UNKNOWN_METHOD;
+ }
+
+ /* NOTREACHED */
+}
+
+/* Get the method number associated with the given string, assumed to
+ * contain an HTTP method. Returns M_INVALID if not recognized.
+ *
+ * This is the first step toward placing method names in a configurable
+ * list. Hopefully it (and other routines) can eventually be moved to
+ * something like a mod_http_methods.c, complete with config stuff.
+ */
+AP_DECLARE(int) ap_method_number_of(const char *method)
+{
+ int len = strlen(method);
+ int which = lookup_builtin_method(method, len);
+
+ if (which != UNKNOWN_METHOD)
+ return which;
+
+ /* check if the method has been dynamically registered */
+ if (methods_registry != NULL) {
+ int *methnum = apr_hash_get(methods_registry, method, len);
+
+ if (methnum != NULL) {
+ return *methnum;
+ }
+ }
+
+ return M_INVALID;
+}
+
+/*
+ * Turn a known method number into a name.
+ */
+AP_DECLARE(const char *) ap_method_name_of(apr_pool_t *p, int methnum)
+{
+ apr_hash_index_t *hi = apr_hash_first(p, methods_registry);
+
+ /* scan through the hash table, looking for a value that matches
+ the provided method number. */
+ for (; hi; hi = apr_hash_next(hi)) {
+ const void *key;
+ void *val;
+
+ apr_hash_this(hi, &key, NULL, &val);
+ if (*(int *)val == methnum)
+ return key;
+ }
+
+ /* it wasn't found in the hash */
+ return NULL;
+}
+
+static long get_chunk_size(char *);
+
+typedef struct http_filter_ctx {
+ apr_off_t remaining;
+ apr_off_t limit;
+ apr_off_t limit_used;
+ enum {
+ BODY_NONE,
+ BODY_LENGTH,
+ BODY_CHUNK
+ } state;
+ int eos_sent;
+} http_ctx_t;
+
+/* This is the HTTP_INPUT filter for HTTP requests and responses from
+ * proxied servers (mod_proxy). It handles chunked and content-length
+ * bodies. This can only be inserted/used after the headers
+ * are successfully parsed.
+ */
+apr_status_t ap_http_filter(ap_filter_t *f, apr_bucket_brigade *b,
+ ap_input_mode_t mode, apr_read_type_e block,
+ apr_off_t readbytes)
+{
+ apr_bucket *e;
+ http_ctx_t *ctx = f->ctx;
+ apr_status_t rv;
+ apr_off_t totalread;
+
+ /* just get out of the way of things we don't want. */
+ if (mode != AP_MODE_READBYTES && mode != AP_MODE_GETLINE) {
+ return ap_get_brigade(f->next, b, mode, block, readbytes);
+ }
+
+ if (!ctx) {
+ const char *tenc, *lenp;
+ f->ctx = ctx = apr_palloc(f->r->pool, sizeof(*ctx));
+ ctx->state = BODY_NONE;
+ ctx->remaining = 0;
+ ctx->limit_used = 0;
+ ctx->eos_sent = 0;
+
+ /* LimitRequestBody does not apply to proxied responses.
+ * Consider implementing this check in its own filter.
+ * Would adding a directive to limit the size of proxied
+ * responses be useful?
+ */
+ if (!f->r->proxyreq) {
+ ctx->limit = ap_get_limit_req_body(f->r);
+ }
+ else {
+ ctx->limit = 0;
+ }
+
+ tenc = apr_table_get(f->r->headers_in, "Transfer-Encoding");
+ lenp = apr_table_get(f->r->headers_in, "Content-Length");
+
+ if (tenc) {
+ if (!strcasecmp(tenc, "chunked")) {
+ ctx->state = BODY_CHUNK;
+ }
+ }
+ else if (lenp) {
+ int conversion_error = 0;
+ char *endstr;
+
+ ctx->state = BODY_LENGTH;
+ errno = 0;
+ ctx->remaining = strtol(lenp, &endstr, 10); /* we depend on ANSI */
+
+ /* This protects us from over/underflow (the errno check),
+ * non-digit chars in the string (excluding leading space)
+ * (the endstr checks) and a negative number. Depending
+ * on the strtol implementation, the errno check may also
+ * trigger on an all whitespace string */
+ if (errno || (endstr && *endstr) || (ctx->remaining < 0)) {
+ conversion_error = 1;
+ }
+
+ if (conversion_error) {
+ apr_bucket_brigade *bb;
+
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, f->r,
+ "Invalid Content-Length");
+
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+ e = ap_bucket_error_create(HTTP_REQUEST_ENTITY_TOO_LARGE, NULL,
+ f->r->pool, f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ return ap_pass_brigade(f->r->output_filters, bb);
+ }
+
+ /* If we have a limit in effect and we know the C-L ahead of
+ * time, stop it here if it is invalid.
+ */
+ if (ctx->limit && ctx->limit < ctx->remaining) {
+ apr_bucket_brigade *bb;
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, f->r,
+ "Requested content-length of %" APR_OFF_T_FMT
+ " is larger than the configured limit"
+ " of %" APR_OFF_T_FMT, ctx->remaining, ctx->limit);
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+ e = ap_bucket_error_create(HTTP_REQUEST_ENTITY_TOO_LARGE, NULL,
+ f->r->pool, f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ return ap_pass_brigade(f->r->output_filters, bb);
+ }
+ }
+
+ /* If we don't have a request entity indicated by the headers, EOS.
+ * (BODY_NONE is a valid intermediate state due to trailers,
+ * but it isn't a valid starting state.)
+ *
+ * RFC 2616 Section 4.4 note 5 states that connection-close
+ * is invalid for a request entity - request bodies must be
+ * denoted by C-L or T-E: chunked.
+ *
+ * Note that since the proxy uses this filter to handle the
+ * proxied *response*, proxy responses MUST be exempt.
+ */
+ if (ctx->state == BODY_NONE && f->r->proxyreq != PROXYREQ_RESPONSE) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ return APR_SUCCESS;
+ }
+
+ /* Since we're about to read data, send 100-Continue if needed.
+ * Only valid on chunked and C-L bodies where the C-L is > 0. */
+ if ((ctx->state == BODY_CHUNK ||
+ (ctx->state == BODY_LENGTH && ctx->remaining > 0)) &&
+ f->r->expecting_100 && f->r->proto_num >= HTTP_VERSION(1,1)) {
+ char *tmp;
+ apr_bucket_brigade *bb;
+
+ tmp = apr_pstrcat(f->r->pool, AP_SERVER_PROTOCOL, " ",
+ status_lines[0], CRLF CRLF, NULL);
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+ e = apr_bucket_pool_create(tmp, strlen(tmp), f->r->pool,
+ f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_HEAD(bb, e);
+ e = apr_bucket_flush_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+
+ ap_pass_brigade(f->c->output_filters, bb);
+ }
+
+ /* We can't read the chunk until after sending 100 if required. */
+ if (ctx->state == BODY_CHUNK) {
+ char line[30];
+ apr_bucket_brigade *bb;
+ apr_size_t len = 30;
+
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+
+ rv = ap_get_brigade(f->next, bb, AP_MODE_GETLINE,
+ APR_BLOCK_READ, 0);
+
+ if (rv == APR_SUCCESS) {
+ rv = apr_brigade_flatten(bb, line, &len);
+ if (rv == APR_SUCCESS) {
+ ctx->remaining = get_chunk_size(line);
+ }
+ }
+ apr_brigade_cleanup(bb);
+
+ /* Detect chunksize error (such as overflow) */
+ if (rv != APR_SUCCESS || ctx->remaining < 0) {
+ ctx->remaining = 0; /* Reset it in case we have to
+ * come back here later */
+ e = ap_bucket_error_create(HTTP_REQUEST_ENTITY_TOO_LARGE, NULL,
+ f->r->pool,
+ f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ return ap_pass_brigade(f->r->output_filters, bb);
+ }
+
+ if (!ctx->remaining) {
+ /* Handle trailers by calling ap_get_mime_headers again! */
+ ctx->state = BODY_NONE;
+ ap_get_mime_headers(f->r);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ return APR_SUCCESS;
+ }
+ }
+ }
+
+ if (ctx->eos_sent) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ return APR_SUCCESS;
+ }
+
+ if (!ctx->remaining) {
+ switch (ctx->state) {
+ case BODY_NONE:
+ break;
+ case BODY_LENGTH:
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ return APR_SUCCESS;
+ case BODY_CHUNK:
+ {
+ char line[30];
+ apr_bucket_brigade *bb;
+ apr_size_t len = 30;
+
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+
+ /* We need to read the CRLF after the chunk. */
+ rv = ap_get_brigade(f->next, bb, AP_MODE_GETLINE,
+ APR_BLOCK_READ, 0);
+ apr_brigade_cleanup(bb);
+
+ if (rv == APR_SUCCESS) {
+ /* Read the real chunk line. */
+ rv = ap_get_brigade(f->next, bb, AP_MODE_GETLINE,
+ APR_BLOCK_READ, 0);
+ if (rv == APR_SUCCESS) {
+ rv = apr_brigade_flatten(bb, line, &len);
+ if (rv == APR_SUCCESS) {
+ ctx->remaining = get_chunk_size(line);
+ }
+ }
+ apr_brigade_cleanup(bb);
+ }
+
+ /* Detect chunksize error (such as overflow) */
+ if (rv != APR_SUCCESS || ctx->remaining < 0) {
+ ctx->remaining = 0; /* Reset it in case we have to
+ * come back here later */
+ e = ap_bucket_error_create(HTTP_REQUEST_ENTITY_TOO_LARGE,
+ NULL, f->r->pool,
+ f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ return ap_pass_brigade(f->r->output_filters, bb);
+ }
+
+ if (!ctx->remaining) {
+ /* Handle trailers by calling ap_get_mime_headers again! */
+ ctx->state = BODY_NONE;
+ ap_get_mime_headers(f->r);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ return APR_SUCCESS;
+ }
+ }
+ break;
+ }
+ }
+
+ /* Ensure that the caller can not go over our boundary point. */
+ if (ctx->state == BODY_LENGTH || ctx->state == BODY_CHUNK) {
+ if (ctx->remaining < readbytes) {
+ readbytes = ctx->remaining;
+ }
+ AP_DEBUG_ASSERT(readbytes > 0);
+ }
+
+ rv = ap_get_brigade(f->next, b, mode, block, readbytes);
+
+ if (rv != APR_SUCCESS) {
+ return rv;
+ }
+
+ /* How many bytes did we just read? */
+ apr_brigade_length(b, 0, &totalread);
+
+ /* If this happens, we have a bucket of unknown length. Die because
+ * it means our assumptions have changed. */
+ AP_DEBUG_ASSERT(totalread >= 0);
+
+ if (ctx->state != BODY_NONE) {
+ ctx->remaining -= totalread;
+ }
+
+ /* If we have no more bytes remaining on a C-L request,
+ * save the callter a roundtrip to discover EOS.
+ */
+ if (ctx->state == BODY_LENGTH && ctx->remaining == 0) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ }
+
+ /* We have a limit in effect. */
+ if (ctx->limit) {
+ /* FIXME: Note that we might get slightly confused on chunked inputs
+ * as we'd need to compensate for the chunk lengths which may not
+ * really count. This seems to be up for interpretation. */
+ ctx->limit_used += totalread;
+ if (ctx->limit < ctx->limit_used) {
+ apr_bucket_brigade *bb;
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, f->r,
+ "Read content-length of %" APR_OFF_T_FMT
+ " is larger than the configured limit"
+ " of %" APR_OFF_T_FMT, ctx->limit_used, ctx->limit);
+ bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+ e = ap_bucket_error_create(HTTP_REQUEST_ENTITY_TOO_LARGE, NULL,
+ f->r->pool,
+ f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ return ap_pass_brigade(f->r->output_filters, bb);
+ }
+ }
+
+ return APR_SUCCESS;
+}
+
+/* The index is found by its offset from the x00 code of each level.
+ * Although this is fast, it will need to be replaced if some nutcase
+ * decides to define a high-numbered code before the lower numbers.
+ * If that sad event occurs, replace the code below with a linear search
+ * from status_lines[shortcut[i]] to status_lines[shortcut[i+1]-1];
+ */
+AP_DECLARE(int) ap_index_of_response(int status)
+{
+ static int shortcut[6] = {0, LEVEL_200, LEVEL_300, LEVEL_400,
+ LEVEL_500, RESPONSE_CODES};
+ int i, pos;
+
+ if (status < 100) { /* Below 100 is illegal for HTTP status */
+ return LEVEL_500;
+ }
+
+ for (i = 0; i < 5; i++) {
+ status -= 100;
+ if (status < 100) {
+ pos = (status + shortcut[i]);
+ if (pos < shortcut[i + 1]) {
+ return pos;
+ }
+ else {
+ return LEVEL_500; /* status unknown (falls in gap) */
+ }
+ }
+ }
+ return LEVEL_500; /* 600 or above is also illegal */
+}
+
+AP_DECLARE(const char *) ap_get_status_line(int status)
+{
+ return status_lines[ap_index_of_response(status)];
+}
+
+typedef struct header_struct {
+ apr_pool_t *pool;
+ apr_bucket_brigade *bb;
+} header_struct;
+
+/* Send a single HTTP header field to the client. Note that this function
+ * is used in calls to table_do(), so their interfaces are co-dependent.
+ * In other words, don't change this one without checking table_do in alloc.c.
+ * It returns true unless there was a write error of some kind.
+ */
+static int form_header_field(header_struct *h,
+ const char *fieldname, const char *fieldval)
+{
+#if APR_CHARSET_EBCDIC
+ char *headfield;
+ apr_size_t len;
+ apr_size_t name_len;
+ apr_size_t val_len;
+ char *next;
+
+ name_len = strlen(fieldname);
+ val_len = strlen(fieldval);
+ len = name_len + val_len + 4; /* 4 for ": " plus CRLF */
+ headfield = (char *)apr_palloc(h->pool, len + 1);
+ memcpy(headfield, fieldname, name_len);
+ next = headfield + name_len;
+ *next++ = ':';
+ *next++ = ' ';
+ memcpy(next, fieldval, val_len);
+ next += val_len;
+ *next++ = CR;
+ *next++ = LF;
+ *next = 0;
+ ap_xlate_proto_to_ascii(headfield, len);
+ apr_brigade_write(h->bb, NULL, NULL, headfield, len);
+#else
+ struct iovec vec[4];
+ struct iovec *v = vec;
+ v->iov_base = (void *)fieldname;
+ v->iov_len = strlen(fieldname);
+ v++;
+ v->iov_base = ": ";
+ v->iov_len = sizeof(": ") - 1;
+ v++;
+ v->iov_base = (void *)fieldval;
+ v->iov_len = strlen(fieldval);
+ v++;
+ v->iov_base = CRLF;
+ v->iov_len = sizeof(CRLF) - 1;
+ apr_brigade_writev(h->bb, NULL, NULL, vec, 4);
+#endif /* !APR_CHARSET_EBCDIC */
+ return 1;
+}
+
+/* Send a request's HTTP response headers to the client.
+ */
+static apr_status_t send_all_header_fields(header_struct *h,
+ const request_rec *r)
+{
+ const apr_array_header_t *elts;
+ const apr_table_entry_t *t_elt;
+ const apr_table_entry_t *t_end;
+ struct iovec *vec;
+ struct iovec *vec_next;
+
+ elts = apr_table_elts(r->headers_out);
+ if (elts->nelts == 0) {
+ return APR_SUCCESS;
+ }
+ t_elt = (const apr_table_entry_t *)(elts->elts);
+ t_end = t_elt + elts->nelts;
+ vec = (struct iovec *)apr_palloc(h->pool, 4 * elts->nelts *
+ sizeof(struct iovec));
+ vec_next = vec;
+
+ /* For each field, generate
+ * name ": " value CRLF
+ */
+ do {
+ vec_next->iov_base = (void*)(t_elt->key);
+ vec_next->iov_len = strlen(t_elt->key);
+ vec_next++;
+ vec_next->iov_base = ": ";
+ vec_next->iov_len = sizeof(": ") - 1;
+ vec_next++;
+ vec_next->iov_base = (void*)(t_elt->val);
+ vec_next->iov_len = strlen(t_elt->val);
+ vec_next++;
+ vec_next->iov_base = CRLF;
+ vec_next->iov_len = sizeof(CRLF) - 1;
+ vec_next++;
+ t_elt++;
+ } while (t_elt < t_end);
+
+#if APR_CHARSET_EBCDIC
+ {
+ apr_size_t len;
+ char *tmp = apr_pstrcatv(r->pool, vec, vec_next - vec, &len);
+ ap_xlate_proto_to_ascii(tmp, len);
+ return apr_brigade_write(h->bb, NULL, NULL, tmp, len);
+ }
+#else
+ return apr_brigade_writev(h->bb, NULL, NULL, vec, vec_next - vec);
+#endif
+}
+
+/* Confirm that the status line is well-formed and matches r->status.
+ * Otherwise, a filter may have negated the status line set by a
+ * handler.
+ * Zap r->status_line if bad.
+ */
+static void validate_status_line(request_rec *r)
+{
+ char *end;
+
+ if (r->status_line
+ && (strlen(r->status_line) <= 4
+ || apr_strtoi64(r->status_line, &end, 10) != r->status
+ || *end != ' '
+ || (end - 3) != r->status_line)) {
+ r->status_line = NULL;
+ }
+}
+
+/*
+ * Determine the protocol to use for the response. Potentially downgrade
+ * to HTTP/1.0 in some situations and/or turn off keepalives.
+ *
+ * also prepare r->status_line.
+ */
+static void basic_http_header_check(request_rec *r,
+ const char **protocol)
+{
+ if (r->assbackwards) {
+ /* no such thing as a response protocol */
+ return;
+ }
+
+ validate_status_line(r);
+
+ if (!r->status_line) {
+ r->status_line = status_lines[ap_index_of_response(r->status)];
+ }
+
+ /* Note that we must downgrade before checking for force responses. */
+ if (r->proto_num > HTTP_VERSION(1,0)
+ && apr_table_get(r->subprocess_env, "downgrade-1.0")) {
+ r->proto_num = HTTP_VERSION(1,0);
+ }
+
+ /* kludge around broken browsers when indicated by force-response-1.0
+ */
+ if (r->proto_num == HTTP_VERSION(1,0)
+ && apr_table_get(r->subprocess_env, "force-response-1.0")) {
+ *protocol = "HTTP/1.0";
+ r->connection->keepalive = AP_CONN_CLOSE;
+ }
+ else {
+ *protocol = AP_SERVER_PROTOCOL;
+ }
+
+}
+
+/* fill "bb" with a barebones/initial HTTP response header */
+static void basic_http_header(request_rec *r, apr_bucket_brigade *bb,
+ const char *protocol)
+{
+ char *date;
+ const char *server;
+ header_struct h;
+ struct iovec vec[4];
+
+ if (r->assbackwards) {
+ /* there are no headers to send */
+ return;
+ }
+
+ /* Output the HTTP/1.x Status-Line and the Date and Server fields */
+
+ vec[0].iov_base = (void *)protocol;
+ vec[0].iov_len = strlen(protocol);
+ vec[1].iov_base = (void *)" ";
+ vec[1].iov_len = sizeof(" ") - 1;
+ vec[2].iov_base = (void *)(r->status_line);
+ vec[2].iov_len = strlen(r->status_line);
+ vec[3].iov_base = (void *)CRLF;
+ vec[3].iov_len = sizeof(CRLF) - 1;
+#if APR_CHARSET_EBCDIC
+ {
+ char *tmp;
+ apr_size_t len;
+ tmp = apr_pstrcatv(r->pool, vec, 4, &len);
+ ap_xlate_proto_to_ascii(tmp, len);
+ apr_brigade_write(bb, NULL, NULL, tmp, len);
+ }
+#else
+ apr_brigade_writev(bb, NULL, NULL, vec, 4);
+#endif
+
+ date = apr_palloc(r->pool, APR_RFC822_DATE_LEN);
+ ap_recent_rfc822_date(date, r->request_time);
+
+ h.pool = r->pool;
+ h.bb = bb;
+ form_header_field(&h, "Date", date);
+
+ /* keep the set-by-proxy server header, otherwise
+ * generate a new server header */
+ if (r->proxyreq != PROXYREQ_NONE) {
+ server = apr_table_get(r->headers_out, "Server");
+ if (server) {
+ form_header_field(&h, "Server", server);
+ }
+ }
+ else {
+ form_header_field(&h, "Server", ap_get_server_version());
+ }
+
+ /* unset so we don't send them again */
+ apr_table_unset(r->headers_out, "Date"); /* Avoid bogosity */
+ apr_table_unset(r->headers_out, "Server");
+}
+
+AP_DECLARE(void) ap_basic_http_header(request_rec *r, apr_bucket_brigade *bb)
+{
+ const char *protocol;
+
+ basic_http_header_check(r, &protocol);
+ basic_http_header(r, bb, protocol);
+}
+
+/* Navigator versions 2.x, 3.x and 4.0 betas up to and including 4.0b2
+ * have a header parsing bug. If the terminating \r\n occur starting
+ * at offset 256, 257 or 258 of output then it will not properly parse
+ * the headers. Curiously it doesn't exhibit this problem at 512, 513.
+ * We are guessing that this is because their initial read of a new request
+ * uses a 256 byte buffer, and subsequent reads use a larger buffer.
+ * So the problem might exist at different offsets as well.
+ *
+ * This should also work on keepalive connections assuming they use the
+ * same small buffer for the first read of each new request.
+ *
+ * At any rate, we check the bytes written so far and, if we are about to
+ * tickle the bug, we instead insert a bogus padding header. Since the bug
+ * manifests as a broken image in Navigator, users blame the server. :(
+ * It is more expensive to check the User-Agent than it is to just add the
+ * bytes, so we haven't used the BrowserMatch feature here.
+ */
+static void terminate_header(apr_bucket_brigade *bb)
+{
+ char tmp[] = "X-Pad: avoid browser bug" CRLF;
+ char crlf[] = CRLF;
+ apr_off_t len;
+ apr_size_t buflen;
+
+ (void) apr_brigade_length(bb, 1, &len);
+
+ if (len >= 255 && len <= 257) {
+ buflen = strlen(tmp);
+ ap_xlate_proto_to_ascii(tmp, buflen);
+ apr_brigade_write(bb, NULL, NULL, tmp, buflen);
+ }
+ buflen = strlen(crlf);
+ ap_xlate_proto_to_ascii(crlf, buflen);
+ apr_brigade_write(bb, NULL, NULL, crlf, buflen);
+}
+
+/* Build the Allow field-value from the request handler method mask.
+ * Note that we always allow TRACE, since it is handled below.
+ */
+static char *make_allow(request_rec *r)
+{
+ char *list;
+ apr_int64_t mask;
+ apr_array_header_t *allow = apr_array_make(r->pool, 10, sizeof(char *));
+ apr_hash_index_t *hi = apr_hash_first(r->pool, methods_registry);
+ /* For TRACE below */
+ core_server_config *conf =
+ ap_get_module_config(r->server->module_config, &core_module);
+
+ mask = r->allowed_methods->method_mask;
+
+ for (; hi; hi = apr_hash_next(hi)) {
+ const void *key;
+ void *val;
+
+ apr_hash_this(hi, &key, NULL, &val);
+ if ((mask & (AP_METHOD_BIT << *(int *)val)) != 0) {
+ *(const char **)apr_array_push(allow) = key;
+
+ /* the M_GET method actually refers to two methods */
+ if (*(int *)val == M_GET)
+ *(const char **)apr_array_push(allow) = "HEAD";
+ }
+ }
+
+ /* TRACE is tested on a per-server basis */
+ if (conf->trace_enable != AP_TRACE_DISABLE)
+ *(const char **)apr_array_push(allow) = "TRACE";
+
+ list = apr_array_pstrcat(r->pool, allow, ',');
+
+ /* ### this is rather annoying. we should enforce registration of
+ ### these methods */
+ if ((mask & (AP_METHOD_BIT << M_INVALID))
+ && (r->allowed_methods->method_list != NULL)
+ && (r->allowed_methods->method_list->nelts != 0)) {
+ int i;
+ char **xmethod = (char **) r->allowed_methods->method_list->elts;
+
+ /*
+ * Append all of the elements of r->allowed_methods->method_list
+ */
+ for (i = 0; i < r->allowed_methods->method_list->nelts; ++i) {
+ list = apr_pstrcat(r->pool, list, ",", xmethod[i], NULL);
+ }
+ }
+
+ return list;
+}
+
+AP_DECLARE_NONSTD(int) ap_send_http_trace(request_rec *r)
+{
+ core_server_config *conf;
+ int rv;
+ apr_bucket_brigade *bb;
+ header_struct h;
+ apr_bucket *b;
+ int body;
+ char *bodyread = NULL, *bodyoff;
+ apr_size_t bodylen = 0;
+ apr_size_t bodybuf;
+ long res;
+
+ if (r->method_number != M_TRACE) {
+ return DECLINED;
+ }
+
+ /* Get the original request */
+ while (r->prev) {
+ r = r->prev;
+ }
+ conf = (core_server_config *)ap_get_module_config(r->server->module_config,
+ &core_module);
+
+ if (conf->trace_enable == AP_TRACE_DISABLE) {
+ apr_table_setn(r->notes, "error-notes",
+ "TRACE denied by server configuration");
+ return HTTP_FORBIDDEN;
+ }
+
+ if (conf->trace_enable == AP_TRACE_EXTENDED)
+ /* XX should be = REQUEST_CHUNKED_PASS */
+ body = REQUEST_CHUNKED_DECHUNK;
+ else
+ body = REQUEST_NO_BODY;
+
+ if ((rv = ap_setup_client_block(r, body))) {
+ if (rv == HTTP_REQUEST_ENTITY_TOO_LARGE)
+ apr_table_setn(r->notes, "error-notes",
+ "TRACE with a request body is not allowed");
+ return rv;
+ }
+
+ if (ap_should_client_block(r)) {
+
+ if (r->remaining > 0) {
+ if (r->remaining > 65536) {
+ apr_table_setn(r->notes, "error-notes",
+ "Extended TRACE request bodies cannot exceed 64k");
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+ /* always 32 extra bytes to catch chunk header exceptions */
+ bodybuf = (apr_size_t)r->remaining + 32;
+ }
+ else {
+ /* Add an extra 8192 for chunk headers */
+ bodybuf = 73730;
+ }
+
+ bodyoff = bodyread = apr_palloc(r->pool, bodybuf);
+
+ /* only while we have enough for a chunked header */
+ while ((!bodylen || bodybuf >= 32) &&
+ (res = ap_get_client_block(r, bodyoff, bodybuf)) > 0) {
+ bodylen += res;
+ bodybuf -= res;
+ bodyoff += res;
+ }
+ if (res > 0 && bodybuf < 32) {
+ /* discard_rest_of_request_body into our buffer */
+ while (ap_get_client_block(r, bodyread, bodylen) > 0)
+ ;
+ apr_table_setn(r->notes, "error-notes",
+ "Extended TRACE request bodies cannot exceed 64k");
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+
+ if (res < 0) {
+ return HTTP_BAD_REQUEST;
+ }
+ }
+
+ ap_set_content_type(r, "message/http");
+
+ /* Now we recreate the request, and echo it back */
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ apr_brigade_putstrs(bb, NULL, NULL, r->the_request, CRLF, NULL);
+ h.pool = r->pool;
+ h.bb = bb;
+ apr_table_do((int (*) (void *, const char *, const char *))
+ form_header_field, (void *) &h, r->headers_in, NULL);
+ apr_brigade_puts(bb, NULL, NULL, CRLF);
+
+ /* If configured to accept a body, echo the body */
+ if (bodylen) {
+ b = apr_bucket_pool_create(bodyread, bodylen,
+ r->pool, bb->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, b);
+ }
+
+ ap_pass_brigade(r->output_filters, bb);
+
+ return DONE;
+}
+
+AP_DECLARE(int) ap_send_http_options(request_rec *r)
+{
+ if (r->assbackwards) {
+ return DECLINED;
+ }
+
+ apr_table_setn(r->headers_out, "Allow", make_allow(r));
+
+ /* the request finalization will send an EOS, which will flush all
+ * the headers out (including the Allow header)
+ */
+
+ return OK;
+}
+
+/* This routine is called by apr_table_do and merges all instances of
+ * the passed field values into a single array that will be further
+ * processed by some later routine. Originally intended to help split
+ * and recombine multiple Vary fields, though it is generic to any field
+ * consisting of comma/space-separated tokens.
+ */
+static int uniq_field_values(void *d, const char *key, const char *val)
+{
+ apr_array_header_t *values;
+ char *start;
+ char *e;
+ char **strpp;
+ int i;
+
+ values = (apr_array_header_t *)d;
+
+ e = apr_pstrdup(values->pool, val);
+
+ do {
+ /* Find a non-empty fieldname */
+
+ while (*e == ',' || apr_isspace(*e)) {
+ ++e;
+ }
+ if (*e == '\0') {
+ break;
+ }
+ start = e;
+ while (*e != '\0' && *e != ',' && !apr_isspace(*e)) {
+ ++e;
+ }
+ if (*e != '\0') {
+ *e++ = '\0';
+ }
+
+ /* Now add it to values if it isn't already represented.
+ * Could be replaced by a ap_array_strcasecmp() if we had one.
+ */
+ for (i = 0, strpp = (char **) values->elts; i < values->nelts;
+ ++i, ++strpp) {
+ if (*strpp && strcasecmp(*strpp, start) == 0) {
+ break;
+ }
+ }
+ if (i == values->nelts) { /* if not found */
+ *(char **)apr_array_push(values) = start;
+ }
+ } while (*e != '\0');
+
+ return 1;
+}
+
+/*
+ * Since some clients choke violently on multiple Vary fields, or
+ * Vary fields with duplicate tokens, combine any multiples and remove
+ * any duplicates.
+ */
+static void fixup_vary(request_rec *r)
+{
+ apr_array_header_t *varies;
+
+ varies = apr_array_make(r->pool, 5, sizeof(char *));
+
+ /* Extract all Vary fields from the headers_out, separate each into
+ * its comma-separated fieldname values, and then add them to varies
+ * if not already present in the array.
+ */
+ apr_table_do((int (*)(void *, const char *, const char *))uniq_field_values,
+ (void *) varies, r->headers_out, "Vary", NULL);
+
+ /* If we found any, replace old Vary fields with unique-ified value */
+
+ if (varies->nelts > 0) {
+ apr_table_setn(r->headers_out, "Vary",
+ apr_array_pstrcat(r->pool, varies, ','));
+ }
+}
+
+AP_DECLARE(void) ap_set_content_type(request_rec *r, const char *ct)
+{
+ if (!ct) {
+ r->content_type = NULL;
+ }
+ else if (!r->content_type || strcmp(r->content_type, ct)) {
+ r->content_type = ct;
+
+ /* Insert filters requested by the AddOutputFiltersByType
+ * configuration directive. Content-type filters must be
+ * inserted after the content handlers have run because
+ * only then, do we reliably know the content-type.
+ */
+ ap_add_output_filters_by_type(r);
+ }
+}
+
+typedef struct header_filter_ctx {
+ int headers_sent;
+} header_filter_ctx;
+
+AP_CORE_DECLARE_NONSTD(apr_status_t) ap_http_header_filter(ap_filter_t *f,
+ apr_bucket_brigade *b)
+{
+ request_rec *r = f->r;
+ conn_rec *c = r->connection;
+ const char *clheader;
+ const char *protocol;
+ apr_bucket *e;
+ apr_bucket_brigade *b2;
+ header_struct h;
+ header_filter_ctx *ctx = f->ctx;
+
+ AP_DEBUG_ASSERT(!r->main);
+
+ if (r->header_only) {
+ if (!ctx) {
+ ctx = f->ctx = apr_pcalloc(r->pool, sizeof(header_filter_ctx));
+ }
+ else if (ctx->headers_sent) {
+ apr_brigade_destroy(b);
+ return OK;
+ }
+ }
+
+ APR_BRIGADE_FOREACH(e, b) {
+ if (e->type == &ap_bucket_type_error) {
+ ap_bucket_error *eb = e->data;
+
+ ap_die(eb->status, r);
+ return AP_FILTER_ERROR;
+ }
+ }
+
+ if (r->assbackwards) {
+ r->sent_bodyct = 1;
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, b);
+ }
+
+ /*
+ * Now that we are ready to send a response, we need to combine the two
+ * header field tables into a single table. If we don't do this, our
+ * later attempts to set or unset a given fieldname might be bypassed.
+ */
+ if (!apr_is_empty_table(r->err_headers_out)) {
+ r->headers_out = apr_table_overlay(r->pool, r->err_headers_out,
+ r->headers_out);
+ }
+
+ /*
+ * Remove the 'Vary' header field if the client can't handle it.
+ * Since this will have nasty effects on HTTP/1.1 caches, force
+ * the response into HTTP/1.0 mode.
+ *
+ * Note: the force-response-1.0 should come before the call to
+ * basic_http_header_check()
+ */
+ if (apr_table_get(r->subprocess_env, "force-no-vary") != NULL) {
+ apr_table_unset(r->headers_out, "Vary");
+ r->proto_num = HTTP_VERSION(1,0);
+ apr_table_set(r->subprocess_env, "force-response-1.0", "1");
+ }
+ else {
+ fixup_vary(r);
+ }
+
+ /*
+ * Now remove any ETag response header field if earlier processing
+ * says so (such as a 'FileETag None' directive).
+ */
+ if (apr_table_get(r->notes, "no-etag") != NULL) {
+ apr_table_unset(r->headers_out, "ETag");
+ }
+
+ /* determine the protocol and whether we should use keepalives. */
+ basic_http_header_check(r, &protocol);
+ ap_set_keepalive(r);
+
+ if (r->chunked) {
+ apr_table_mergen(r->headers_out, "Transfer-Encoding", "chunked");
+ apr_table_unset(r->headers_out, "Content-Length");
+ }
+
+ apr_table_setn(r->headers_out, "Content-Type",
+ ap_make_content_type(r, r->content_type));
+
+ if (r->content_encoding) {
+ apr_table_setn(r->headers_out, "Content-Encoding",
+ r->content_encoding);
+ }
+
+ if (!apr_is_empty_array(r->content_languages)) {
+ int i;
+ char **languages = (char **)(r->content_languages->elts);
+ for (i = 0; i < r->content_languages->nelts; ++i) {
+ apr_table_mergen(r->headers_out, "Content-Language", languages[i]);
+ }
+ }
+
+ /*
+ * Control cachability for non-cachable responses if not already set by
+ * some other part of the server configuration.
+ */
+ if (r->no_cache && !apr_table_get(r->headers_out, "Expires")) {
+ char *date = apr_palloc(r->pool, APR_RFC822_DATE_LEN);
+ ap_recent_rfc822_date(date, r->request_time);
+ apr_table_addn(r->headers_out, "Expires", date);
+ }
+
+ /* This is a hack, but I can't find anyway around it. The idea is that
+ * we don't want to send out 0 Content-Lengths if it is a head request.
+ * This happens when modules try to outsmart the server, and return
+ * if they see a HEAD request. Apache 1.3 handlers were supposed to
+ * just return in that situation, and the core handled the HEAD. In
+ * 2.0, if a handler returns, then the core sends an EOS bucket down
+ * the filter stack, and the content-length filter computes a C-L of
+ * zero and that gets put in the headers, and we end up sending a
+ * zero C-L to the client. We can't just remove the C-L filter,
+ * because well behaved 2.0 handlers will send their data down the stack,
+ * and we will compute a real C-L for the head request. RBB
+ */
+ if (r->header_only
+ && (clheader = apr_table_get(r->headers_out, "Content-Length"))
+ && !strcmp(clheader, "0")) {
+ apr_table_unset(r->headers_out, "Content-Length");
+ }
+
+ b2 = apr_brigade_create(r->pool, c->bucket_alloc);
+ basic_http_header(r, b2, protocol);
+
+ h.pool = r->pool;
+ h.bb = b2;
+
+ if (r->status == HTTP_NOT_MODIFIED) {
+ apr_table_do((int (*)(void *, const char *, const char *)) form_header_field,
+ (void *) &h, r->headers_out,
+ "Connection",
+ "Keep-Alive",
+ "ETag",
+ "Content-Location",
+ "Expires",
+ "Cache-Control",
+ "Vary",
+ "Warning",
+ "WWW-Authenticate",
+ "Proxy-Authenticate",
+ "Set-Cookie",
+ "Set-Cookie2",
+ NULL);
+ }
+ else {
+ send_all_header_fields(&h, r);
+ }
+
+ terminate_header(b2);
+
+ ap_pass_brigade(f->next, b2);
+
+ if (r->header_only) {
+ apr_brigade_destroy(b);
+ ctx->headers_sent = 1;
+ return OK;
+ }
+
+ r->sent_bodyct = 1; /* Whatever follows is real body stuff... */
+
+ if (r->chunked) {
+ /* We can't add this filter until we have already sent the headers.
+ * If we add it before this point, then the headers will be chunked
+ * as well, and that is just wrong.
+ */
+ ap_add_output_filter("CHUNK", NULL, r, r->connection);
+ }
+
+ /* Don't remove this filter until after we have added the CHUNK filter.
+ * Otherwise, f->next won't be the CHUNK filter and thus the first
+ * brigade won't be chunked properly.
+ */
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, b);
+}
+
+/* Here we deal with getting the request message body from the client.
+ * Whether or not the request contains a body is signaled by the presence
+ * of a non-zero Content-Length or by a Transfer-Encoding: chunked.
+ *
+ * Note that this is more complicated than it was in Apache 1.1 and prior
+ * versions, because chunked support means that the module does less.
+ *
+ * The proper procedure is this:
+ *
+ * 1. Call setup_client_block() near the beginning of the request
+ * handler. This will set up all the necessary properties, and will
+ * return either OK, or an error code. If the latter, the module should
+ * return that error code. The second parameter selects the policy to
+ * apply if the request message indicates a body, and how a chunked
+ * transfer-coding should be interpreted. Choose one of
+ *
+ * REQUEST_NO_BODY Send 413 error if message has any body
+ * REQUEST_CHUNKED_ERROR Send 411 error if body without Content-Length
+ * REQUEST_CHUNKED_DECHUNK If chunked, remove the chunks for me.
+ *
+ * In order to use the last two options, the caller MUST provide a buffer
+ * large enough to hold a chunk-size line, including any extensions.
+ *
+ * 2. When you are ready to read a body (if any), call should_client_block().
+ * This will tell the module whether or not to read input. If it is 0,
+ * the module should assume that there is no message body to read.
+ * This step also sends a 100 Continue response to HTTP/1.1 clients,
+ * so should not be called until the module is *definitely* ready to
+ * read content. (otherwise, the point of the 100 response is defeated).
+ * Never call this function more than once.
+ *
+ * 3. Finally, call get_client_block in a loop. Pass it a buffer and its size.
+ * It will put data into the buffer (not necessarily a full buffer), and
+ * return the length of the input block. When it is done reading, it will
+ * return 0 if EOF, or -1 if there was an error.
+ * If an error occurs on input, we force an end to keepalive.
+ */
+
+AP_DECLARE(int) ap_setup_client_block(request_rec *r, int read_policy)
+{
+ const char *tenc = apr_table_get(r->headers_in, "Transfer-Encoding");
+ const char *lenp = apr_table_get(r->headers_in, "Content-Length");
+
+ r->read_body = read_policy;
+ r->read_chunked = 0;
+ r->remaining = 0;
+
+ if (tenc) {
+ if (strcasecmp(tenc, "chunked")) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+ "Unknown Transfer-Encoding %s", tenc);
+ return HTTP_NOT_IMPLEMENTED;
+ }
+ if (r->read_body == REQUEST_CHUNKED_ERROR) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+ "chunked Transfer-Encoding forbidden: %s", r->uri);
+ return (lenp) ? HTTP_BAD_REQUEST : HTTP_LENGTH_REQUIRED;
+ }
+
+ r->read_chunked = 1;
+ }
+ else if (lenp) {
+ int conversion_error = 0;
+ char *endstr;
+
+ errno = 0;
+ r->remaining = strtol(lenp, &endstr, 10); /* depend on ANSI */
+
+ /* See comments in ap_http_filter() */
+ if (errno || (endstr && *endstr) || (r->remaining < 0)) {
+ conversion_error = 1;
+ }
+
+ if (conversion_error) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+ "Invalid Content-Length");
+ return HTTP_BAD_REQUEST;
+ }
+ }
+
+ if ((r->read_body == REQUEST_NO_BODY)
+ && (r->read_chunked || (r->remaining > 0))) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+ "%s with body is not allowed for %s", r->method, r->uri);
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+
+#ifdef AP_DEBUG
+ {
+ /* Make sure ap_getline() didn't leave any droppings. */
+ core_request_config *req_cfg =
+ (core_request_config *)ap_get_module_config(r->request_config,
+ &core_module);
+ AP_DEBUG_ASSERT(APR_BRIGADE_EMPTY(req_cfg->bb));
+ }
+#endif
+
+ return OK;
+}
+
+AP_DECLARE(int) ap_should_client_block(request_rec *r)
+{
+ /* First check if we have already read the request body */
+
+ if (r->read_length || (!r->read_chunked && (r->remaining <= 0))) {
+ return 0;
+ }
+
+ return 1;
+}
+
+/**
+ * Parse a chunk extension, detect overflow.
+ * There are two error cases:
+ * 1) If the conversion would require too many bits, a -1 is returned.
+ * 2) If the conversion used the correct number of bits, but an overflow
+ * caused only the sign bit to flip, then that negative number is
+ * returned.
+ * In general, any negative number can be considered an overflow error.
+ */
+static long get_chunk_size(char *b)
+{
+ long chunksize = 0;
+ size_t chunkbits = sizeof(long) * 8;
+
+ ap_xlate_proto_from_ascii(b, strlen(b));
+
+ /* Skip leading zeros */
+ while (*b == '0') {
+ ++b;
+ }
+
+ while (apr_isxdigit(*b) && (chunkbits > 0)) {
+ int xvalue = 0;
+
+ if (*b >= '0' && *b <= '9') {
+ xvalue = *b - '0';
+ }
+ else if (*b >= 'A' && *b <= 'F') {
+ xvalue = *b - 'A' + 0xa;
+ }
+ else if (*b >= 'a' && *b <= 'f') {
+ xvalue = *b - 'a' + 0xa;
+ }
+
+ chunksize = (chunksize << 4) | xvalue;
+ chunkbits -= 4;
+ ++b;
+ }
+ if (apr_isxdigit(*b) && (chunkbits <= 0)) {
+ /* overflow */
+ return -1;
+ }
+
+ return chunksize;
+}
+
+/* get_client_block is called in a loop to get the request message body.
+ * This is quite simple if the client includes a content-length
+ * (the normal case), but gets messy if the body is chunked. Note that
+ * r->remaining is used to maintain state across calls and that
+ * r->read_length is the total number of bytes given to the caller
+ * across all invocations. It is messy because we have to be careful not
+ * to read past the data provided by the client, since these reads block.
+ * Returns 0 on End-of-body, -1 on error or premature chunk end.
+ *
+ */
+AP_DECLARE(long) ap_get_client_block(request_rec *r, char *buffer,
+ apr_size_t bufsiz)
+{
+ apr_status_t rv;
+ apr_bucket_brigade *bb;
+
+ if (r->remaining < 0 || (!r->read_chunked && r->remaining == 0)) {
+ return 0;
+ }
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ if (bb == NULL) {
+ r->connection->keepalive = AP_CONN_CLOSE;
+ return -1;
+ }
+
+ rv = ap_get_brigade(r->input_filters, bb, AP_MODE_READBYTES,
+ APR_BLOCK_READ, bufsiz);
+
+ /* We lose the failure code here. This is why ap_get_client_block should
+ * not be used.
+ */
+ if (rv != APR_SUCCESS) {
+ /* if we actually fail here, we want to just return and
+ * stop trying to read data from the client.
+ */
+ r->connection->keepalive = AP_CONN_CLOSE;
+ apr_brigade_destroy(bb);
+ return -1;
+ }
+
+ /* If this fails, it means that a filter is written incorrectly and that
+ * it needs to learn how to properly handle APR_BLOCK_READ requests by
+ * returning data when requested.
+ */
+ AP_DEBUG_ASSERT(!APR_BRIGADE_EMPTY(bb));
+
+ /* Check to see if EOS in the brigade.
+ *
+ * If so, we have to leave a nugget for the *next* ap_get_client_block
+ * call to return 0.
+ */
+ if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) {
+ if (r->read_chunked) {
+ r->remaining = -1;
+ }
+ else {
+ r->remaining = 0;
+ }
+ }
+
+ rv = apr_brigade_flatten(bb, buffer, &bufsiz);
+ if (rv != APR_SUCCESS) {
+ apr_brigade_destroy(bb);
+ return -1;
+ }
+
+ /* XXX yank me? */
+ r->read_length += bufsiz;
+
+ apr_brigade_destroy(bb);
+ return bufsiz;
+}
+
+/* In HTTP/1.1, any method can have a body. However, most GET handlers
+ * wouldn't know what to do with a request body if they received one.
+ * This helper routine tests for and reads any message body in the request,
+ * simply discarding whatever it receives. We need to do this because
+ * failing to read the request body would cause it to be interpreted
+ * as the next request on a persistent connection.
+ *
+ * Since we return an error status if the request is malformed, this
+ * routine should be called at the beginning of a no-body handler, e.g.,
+ *
+ * if ((retval = ap_discard_request_body(r)) != OK) {
+ * return retval;
+ * }
+ */
+AP_DECLARE(int) ap_discard_request_body(request_rec *r)
+{
+ apr_bucket_brigade *bb;
+ int rv, seen_eos;
+
+ /* Sometimes we'll get in a state where the input handling has
+ * detected an error where we want to drop the connection, so if
+ * that's the case, don't read the data as that is what we're trying
+ * to avoid.
+ *
+ * This function is also a no-op on a subrequest.
+ */
+ if (r->main || r->connection->keepalive == AP_CONN_CLOSE ||
+ ap_status_drops_connection(r->status)) {
+ return OK;
+ }
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ seen_eos = 0;
+ do {
+ apr_bucket *bucket;
+
+ rv = ap_get_brigade(r->input_filters, bb, AP_MODE_READBYTES,
+ APR_BLOCK_READ, HUGE_STRING_LEN);
+
+ if (rv != APR_SUCCESS) {
+ /* FIXME: If we ever have a mapping from filters (apr_status_t)
+ * to HTTP error codes, this would be a good place for them.
+ *
+ * If we received the special case AP_FILTER_ERROR, it means
+ * that the filters have already handled this error.
+ * Otherwise, we should assume we have a bad request.
+ */
+ if (rv == AP_FILTER_ERROR) {
+ apr_brigade_destroy(bb);
+ return rv;
+ }
+ else {
+ apr_brigade_destroy(bb);
+ return HTTP_BAD_REQUEST;
+ }
+ }
+
+ APR_BRIGADE_FOREACH(bucket, bb) {
+ const char *data;
+ apr_size_t len;
+
+ if (APR_BUCKET_IS_EOS(bucket)) {
+ seen_eos = 1;
+ break;
+ }
+
+ /* These are metadata buckets. */
+ if (bucket->length == 0) {
+ continue;
+ }
+
+ /* We MUST read because in case we have an unknown-length
+ * bucket or one that morphs, we want to exhaust it.
+ */
+ rv = apr_bucket_read(bucket, &data, &len, APR_BLOCK_READ);
+ if (rv != APR_SUCCESS) {
+ apr_brigade_destroy(bb);
+ return HTTP_BAD_REQUEST;
+ }
+ }
+ apr_brigade_cleanup(bb);
+ } while (!seen_eos);
+
+ return OK;
+}
+
+static const char *add_optional_notes(request_rec *r,
+ const char *prefix,
+ const char *key,
+ const char *suffix)
+{
+ const char *notes, *result;
+
+ if ((notes = apr_table_get(r->notes, key)) == NULL) {
+ result = apr_pstrcat(r->pool, prefix, suffix, NULL);
+ }
+ else {
+ result = apr_pstrcat(r->pool, prefix, notes, suffix, NULL);
+ }
+
+ return result;
+}
+
+/* construct and return the default error message for a given
+ * HTTP defined error code
+ */
+static const char *get_canned_error_string(int status,
+ request_rec *r,
+ const char *location)
+{
+ apr_pool_t *p = r->pool;
+ const char *error_notes, *h1, *s1;
+
+ switch (status) {
+ case HTTP_MOVED_PERMANENTLY:
+ case HTTP_MOVED_TEMPORARILY:
+ case HTTP_TEMPORARY_REDIRECT:
+ return(apr_pstrcat(p,
+ "<p>The document has moved <a href=\"",
+ ap_escape_html(r->pool, location),
+ "\">here</a>.</p>\n",
+ NULL));
+ case HTTP_SEE_OTHER:
+ return(apr_pstrcat(p,
+ "<p>The answer to your request is located "
+ "<a href=\"",
+ ap_escape_html(r->pool, location),
+ "\">here</a>.</p>\n",
+ NULL));
+ case HTTP_USE_PROXY:
+ return(apr_pstrcat(p,
+ "<p>This resource is only accessible "
+ "through the proxy\n",
+ ap_escape_html(r->pool, location),
+ "<br />\nYou will need to configure "
+ "your client to use that proxy.</p>\n",
+ NULL));
+ case HTTP_PROXY_AUTHENTICATION_REQUIRED:
+ case HTTP_UNAUTHORIZED:
+ return("<p>This server could not verify that you\n"
+ "are authorized to access the document\n"
+ "requested. Either you supplied the wrong\n"
+ "credentials (e.g., bad password), or your\n"
+ "browser doesn't understand how to supply\n"
+ "the credentials required.</p>\n");
+ case HTTP_BAD_REQUEST:
+ return(add_optional_notes(r,
+ "<p>Your browser sent a request that "
+ "this server could not understand.<br />\n",
+ "error-notes",
+ "</p>\n"));
+ case HTTP_FORBIDDEN:
+ return(apr_pstrcat(p,
+ "<p>You don't have permission to access ",
+ ap_escape_html(r->pool, r->uri),
+ "\non this server.</p>\n",
+ NULL));
+ case HTTP_NOT_FOUND:
+ return(apr_pstrcat(p,
+ "<p>The requested URL ",
+ ap_escape_html(r->pool, r->uri),
+ " was not found on this server.</p>\n",
+ NULL));
+ case HTTP_METHOD_NOT_ALLOWED:
+ return(apr_pstrcat(p,
+ "<p>The requested method ",
+ ap_escape_html(r->pool, r->method),
+ " is not allowed for the URL ",
+ ap_escape_html(r->pool, r->uri),
+ ".</p>\n",
+ NULL));
+ case HTTP_NOT_ACCEPTABLE:
+ s1 = apr_pstrcat(p,
+ "<p>An appropriate representation of the "
+ "requested resource ",
+ ap_escape_html(r->pool, r->uri),
+ " could not be found on this server.</p>\n",
+ NULL);
+ return(add_optional_notes(r, s1, "variant-list", ""));
+ case HTTP_MULTIPLE_CHOICES:
+ return(add_optional_notes(r, "", "variant-list", ""));
+ case HTTP_LENGTH_REQUIRED:
+ s1 = apr_pstrcat(p,
+ "<p>A request of the requested method ",
+ ap_escape_html(r->pool, r->method),
+ " requires a valid Content-length.<br />\n",
+ NULL);
+ return(add_optional_notes(r, s1, "error-notes", "</p>\n"));
+ case HTTP_PRECONDITION_FAILED:
+ return(apr_pstrcat(p,
+ "<p>The precondition on the request "
+ "for the URL ",
+ ap_escape_html(r->pool, r->uri),
+ " evaluated to false.</p>\n",
+ NULL));
+ case HTTP_NOT_IMPLEMENTED:
+ s1 = apr_pstrcat(p,
+ "<p>",
+ ap_escape_html(r->pool, r->method), " to ",
+ ap_escape_html(r->pool, r->uri),
+ " not supported.<br />\n",
+ NULL);
+ return(add_optional_notes(r, s1, "error-notes", "</p>\n"));
+ case HTTP_BAD_GATEWAY:
+ s1 = "<p>The proxy server received an invalid" CRLF
+ "response from an upstream server.<br />" CRLF;
+ return(add_optional_notes(r, s1, "error-notes", "</p>\n"));
+ case HTTP_VARIANT_ALSO_VARIES:
+ return(apr_pstrcat(p,
+ "<p>A variant for the requested "
+ "resource\n<pre>\n",
+ ap_escape_html(r->pool, r->uri),
+ "\n</pre>\nis itself a negotiable resource. "
+ "This indicates a configuration error.</p>\n",
+ NULL));
+ case HTTP_REQUEST_TIME_OUT:
+ return("<p>Server timeout waiting for the HTTP request from the client.</p>\n");
+ case HTTP_GONE:
+ return(apr_pstrcat(p,
+ "<p>The requested resource<br />",
+ ap_escape_html(r->pool, r->uri),
+ "<br />\nis no longer available on this server "
+ "and there is no forwarding address.\n"
+ "Please remove all references to this "
+ "resource.</p>\n",
+ NULL));
+ case HTTP_REQUEST_ENTITY_TOO_LARGE:
+ return(apr_pstrcat(p,
+ "The requested resource<br />",
+ ap_escape_html(r->pool, r->uri), "<br />\n",
+ "does not allow request data with ",
+ ap_escape_html(r->pool, r->method),
+ " requests, or the amount of data provided in\n"
+ "the request exceeds the capacity limit.\n",
+ NULL));
+ case HTTP_REQUEST_URI_TOO_LARGE:
+ s1 = "<p>The requested URL's length exceeds the capacity\n"
+ "limit for this server.<br />\n";
+ return(add_optional_notes(r, s1, "error-notes", "</p>\n"));
+ case HTTP_UNSUPPORTED_MEDIA_TYPE:
+ return("<p>The supplied request data is not in a format\n"
+ "acceptable for processing by this resource.</p>\n");
+ case HTTP_RANGE_NOT_SATISFIABLE:
+ return("<p>None of the range-specifier values in the Range\n"
+ "request-header field overlap the current extent\n"
+ "of the selected resource.</p>\n");
+ case HTTP_EXPECTATION_FAILED:
+ return(apr_pstrcat(p,
+ "<p>The expectation given in the Expect "
+ "request-header"
+ "\nfield could not be met by this server.</p>\n"
+ "<p>The client sent<pre>\n Expect: ",
+ ap_escape_html(r->pool, apr_table_get(r->headers_in, "Expect")),
+ "\n</pre>\n"
+ "but we only allow the 100-continue "
+ "expectation.</p>\n",
+ NULL));
+ case HTTP_UNPROCESSABLE_ENTITY:
+ return("<p>The server understands the media type of the\n"
+ "request entity, but was unable to process the\n"
+ "contained instructions.</p>\n");
+ case HTTP_LOCKED:
+ return("<p>The requested resource is currently locked.\n"
+ "The lock must be released or proper identification\n"
+ "given before the method can be applied.</p>\n");
+ case HTTP_FAILED_DEPENDENCY:
+ return("<p>The method could not be performed on the resource\n"
+ "because the requested action depended on another\n"
+ "action and that other action failed.</p>\n");
+ case HTTP_UPGRADE_REQUIRED:
+ return("<p>The requested resource can only be retrieved\n"
+ "using SSL. The server is willing to upgrade the current\n"
+ "connection to SSL, but your client doesn't support it.\n"
+ "Either upgrade your client, or try requesting the page\n"
+ "using https://\n");
+ case HTTP_INSUFFICIENT_STORAGE:
+ return("<p>The method could not be performed on the resource\n"
+ "because the server is unable to store the\n"
+ "representation needed to successfully complete the\n"
+ "request. There is insufficient free space left in\n"
+ "your storage allocation.</p>\n");
+ case HTTP_SERVICE_UNAVAILABLE:
+ return("<p>The server is temporarily unable to service your\n"
+ "request due to maintenance downtime or capacity\n"
+ "problems. Please try again later.</p>\n");
+ case HTTP_GATEWAY_TIME_OUT:
+ return("<p>The proxy server did not receive a timely response\n"
+ "from the upstream server.</p>\n");
+ case HTTP_NOT_EXTENDED:
+ return("<p>A mandatory extension policy in the request is not\n"
+ "accepted by the server for this resource.</p>\n");
+ default: /* HTTP_INTERNAL_SERVER_ERROR */
+ /*
+ * This comparison to expose error-notes could be modified to
+ * use a configuration directive and export based on that
+ * directive. For now "*" is used to designate an error-notes
+ * that is totally safe for any user to see (ie lacks paths,
+ * database passwords, etc.)
+ */
+ if (((error_notes = apr_table_get(r->notes,
+ "error-notes")) != NULL)
+ && (h1 = apr_table_get(r->notes, "verbose-error-to")) != NULL
+ && (strcmp(h1, "*") == 0)) {
+ return(apr_pstrcat(p, error_notes, "<p />\n", NULL));
+ }
+ else {
+ return(apr_pstrcat(p,
+ "<p>The server encountered an internal "
+ "error or\n"
+ "misconfiguration and was unable to complete\n"
+ "your request.</p>\n"
+ "<p>Please contact the server "
+ "administrator,\n ",
+ ap_escape_html(r->pool,
+ r->server->server_admin),
+ " and inform them of the time the "
+ "error occurred,\n"
+ "and anything you might have done that "
+ "may have\n"
+ "caused the error.</p>\n"
+ "<p>More information about this error "
+ "may be available\n"
+ "in the server error log.</p>\n",
+ NULL));
+ }
+ /*
+ * It would be nice to give the user the information they need to
+ * fix the problem directly since many users don't have access to
+ * the error_log (think University sites) even though they can easily
+ * get this error by misconfiguring an htaccess file. However, the
+ * e error notes tend to include the real file pathname in this case,
+ * which some people consider to be a breach of privacy. Until we
+ * can figure out a way to remove the pathname, leave this commented.
+ *
+ * if ((error_notes = apr_table_get(r->notes,
+ * "error-notes")) != NULL) {
+ * return(apr_pstrcat(p, error_notes, "<p />\n", NULL);
+ * }
+ * else {
+ * return "";
+ * }
+ */
+ }
+}
+
+/* We should have named this send_canned_response, since it is used for any
+ * response that can be generated by the server from the request record.
+ * This includes all 204 (no content), 3xx (redirect), 4xx (client error),
+ * and 5xx (server error) messages that have not been redirected to another
+ * handler via the ErrorDocument feature.
+ */
+AP_DECLARE(void) ap_send_error_response(request_rec *r, int recursive_error)
+{
+ int status = r->status;
+ int idx = ap_index_of_response(status);
+ char *custom_response;
+ const char *location = apr_table_get(r->headers_out, "Location");
+
+ /* At this point, we are starting the response over, so we have to reset
+ * this value.
+ */
+ r->eos_sent = 0;
+
+ /* and we need to get rid of any RESOURCE filters that might be lurking
+ * around, thinking they are in the middle of the original request
+ */
+
+ r->output_filters = r->proto_output_filters;
+
+ ap_run_insert_error_filter(r);
+
+ /*
+ * It's possible that the Location field might be in r->err_headers_out
+ * instead of r->headers_out; use the latter if possible, else the
+ * former.
+ */
+ if (location == NULL) {
+ location = apr_table_get(r->err_headers_out, "Location");
+ }
+ /* We need to special-case the handling of 204 and 304 responses,
+ * since they have specific HTTP requirements and do not include a
+ * message body. Note that being assbackwards here is not an option.
+ */
+ if (status == HTTP_NOT_MODIFIED) {
+ ap_finalize_request_protocol(r);
+ return;
+ }
+
+ if (status == HTTP_NO_CONTENT) {
+ ap_finalize_request_protocol(r);
+ return;
+ }
+
+ if (!r->assbackwards) {
+ apr_table_t *tmp = r->headers_out;
+
+ /* For all HTTP/1.x responses for which we generate the message,
+ * we need to avoid inheriting the "normal status" header fields
+ * that may have been set by the request handler before the
+ * error or redirect, except for Location on external redirects.
+ */
+ r->headers_out = r->err_headers_out;
+ r->err_headers_out = tmp;
+ apr_table_clear(r->err_headers_out);
+
+ if (ap_is_HTTP_REDIRECT(status) || (status == HTTP_CREATED)) {
+ if ((location != NULL) && *location) {
+ apr_table_setn(r->headers_out, "Location", location);
+ }
+ else {
+ location = ""; /* avoids coredump when printing, below */
+ }
+ }
+
+ r->content_languages = NULL;
+ r->content_encoding = NULL;
+ r->clength = 0;
+
+ if (apr_table_get(r->subprocess_env,
+ "suppress-error-charset") != NULL) {
+ core_request_config *request_conf =
+ ap_get_module_config(r->request_config, &core_module);
+ request_conf->suppress_charset = 1; /* avoid adding default
+ * charset later
+ */
+ ap_set_content_type(r, "text/html");
+ }
+ else {
+ ap_set_content_type(r, "text/html; charset=iso-8859-1");
+ }
+
+ if ((status == HTTP_METHOD_NOT_ALLOWED)
+ || (status == HTTP_NOT_IMPLEMENTED)) {
+ apr_table_setn(r->headers_out, "Allow", make_allow(r));
+ }
+
+ if (r->header_only) {
+ ap_finalize_request_protocol(r);
+ return;
+ }
+ }
+
+ if ((custom_response = ap_response_code_string(r, idx))) {
+ /*
+ * We have a custom response output. This should only be
+ * a text-string to write back. But if the ErrorDocument
+ * was a local redirect and the requested resource failed
+ * for any reason, the custom_response will still hold the
+ * redirect URL. We don't really want to output this URL
+ * as a text message, so first check the custom response
+ * string to ensure that it is a text-string (using the
+ * same test used in ap_die(), i.e. does it start with a ").
+ *
+ * If it's not a text string, we've got a recursive error or
+ * an external redirect. If it's a recursive error, ap_die passes
+ * us the second error code so we can write both, and has already
+ * backed up to the original error. If it's an external redirect,
+ * it hasn't happened yet; we may never know if it fails.
+ */
+ if (custom_response[0] == '\"') {
+ ap_rputs(custom_response + 1, r);
+ ap_finalize_request_protocol(r);
+ return;
+ }
+ }
+ {
+ const char *title = status_lines[idx];
+ const char *h1;
+
+ /* Accept a status_line set by a module, but only if it begins
+ * with the 3 digit status code
+ */
+ if (r->status_line != NULL
+ && strlen(r->status_line) > 4 /* long enough */
+ && apr_isdigit(r->status_line[0])
+ && apr_isdigit(r->status_line[1])
+ && apr_isdigit(r->status_line[2])
+ && apr_isspace(r->status_line[3])
+ && apr_isalnum(r->status_line[4])) {
+ title = r->status_line;
+ }
+
+ /* folks decided they didn't want the error code in the H1 text */
+ h1 = &title[4];
+
+ /* can't count on a charset filter being in place here,
+ * so do ebcdic->ascii translation explicitly (if needed)
+ */
+
+ ap_rvputs_proto_in_ascii(r,
+ DOCTYPE_HTML_2_0
+ "<html><head>\n<title>", title,
+ "</title>\n</head><body>\n<h1>", h1, "</h1>\n",
+ NULL);
+
+ ap_rvputs_proto_in_ascii(r,
+ get_canned_error_string(status, r, location),
+ NULL);
+
+ if (recursive_error) {
+ ap_rvputs_proto_in_ascii(r, "<p>Additionally, a ",
+ status_lines[ap_index_of_response(recursive_error)],
+ "\nerror was encountered while trying to use an "
+ "ErrorDocument to handle the request.</p>\n", NULL);
+ }
+ ap_rvputs_proto_in_ascii(r, ap_psignature("<hr>\n", r), NULL);
+ ap_rvputs_proto_in_ascii(r, "</body></html>\n", NULL);
+ }
+ ap_finalize_request_protocol(r);
+}
+
+/*
+ * Create a new method list with the specified number of preallocated
+ * extension slots.
+ */
+AP_DECLARE(ap_method_list_t *) ap_make_method_list(apr_pool_t *p, int nelts)
+{
+ ap_method_list_t *ml;
+
+ ml = (ap_method_list_t *) apr_palloc(p, sizeof(ap_method_list_t));
+ ml->method_mask = 0;
+ ml->method_list = apr_array_make(p, nelts, sizeof(char *));
+ return ml;
+}
+
+/*
+ * Make a copy of a method list (primarily for subrequests that may
+ * subsequently change it; don't want them changing the parent's, too!).
+ */
+AP_DECLARE(void) ap_copy_method_list(ap_method_list_t *dest,
+ ap_method_list_t *src)
+{
+ int i;
+ char **imethods;
+ char **omethods;
+
+ dest->method_mask = src->method_mask;
+ imethods = (char **) src->method_list->elts;
+ for (i = 0; i < src->method_list->nelts; ++i) {
+ omethods = (char **) apr_array_push(dest->method_list);
+ *omethods = apr_pstrdup(dest->method_list->pool, imethods[i]);
+ }
+}
+
+/*
+ * Invoke a callback routine for each method in the specified list.
+ */
+AP_DECLARE_NONSTD(void) ap_method_list_do(int (*comp) (void *urec,
+ const char *mname,
+ int mnum),
+ void *rec,
+ const ap_method_list_t *ml, ...)
+{
+ va_list vp;
+ va_start(vp, ml);
+ ap_method_list_vdo(comp, rec, ml, vp);
+ va_end(vp);
+}
+
+AP_DECLARE(void) ap_method_list_vdo(int (*comp) (void *mrec,
+ const char *mname,
+ int mnum),
+ void *rec, const ap_method_list_t *ml,
+ va_list vp)
+{
+
+}
+
+/*
+ * Return true if the specified HTTP method is in the provided
+ * method list.
+ */
+AP_DECLARE(int) ap_method_in_list(ap_method_list_t *l, const char *method)
+{
+ int methnum;
+ int i;
+ char **methods;
+
+ /*
+ * If it's one of our known methods, use the shortcut and check the
+ * bitmask.
+ */
+ methnum = ap_method_number_of(method);
+ if (methnum != M_INVALID) {
+ return !!(l->method_mask & (AP_METHOD_BIT << methnum));
+ }
+ /*
+ * Otherwise, see if the method name is in the array or string names
+ */
+ if ((l->method_list == NULL) || (l->method_list->nelts == 0)) {
+ return 0;
+ }
+ methods = (char **)l->method_list->elts;
+ for (i = 0; i < l->method_list->nelts; ++i) {
+ if (strcmp(method, methods[i]) == 0) {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * Add the specified method to a method list (if it isn't already there).
+ */
+AP_DECLARE(void) ap_method_list_add(ap_method_list_t *l, const char *method)
+{
+ int methnum;
+ int i;
+ const char **xmethod;
+ char **methods;
+
+ /*
+ * If it's one of our known methods, use the shortcut and use the
+ * bitmask.
+ */
+ methnum = ap_method_number_of(method);
+ l->method_mask |= (AP_METHOD_BIT << methnum);
+ if (methnum != M_INVALID) {
+ return;
+ }
+ /*
+ * Otherwise, see if the method name is in the array of string names.
+ */
+ if (l->method_list->nelts != 0) {
+ methods = (char **)l->method_list->elts;
+ for (i = 0; i < l->method_list->nelts; ++i) {
+ if (strcmp(method, methods[i]) == 0) {
+ return;
+ }
+ }
+ }
+ xmethod = (const char **) apr_array_push(l->method_list);
+ *xmethod = method;
+}
+
+/*
+ * Remove the specified method from a method list.
+ */
+AP_DECLARE(void) ap_method_list_remove(ap_method_list_t *l,
+ const char *method)
+{
+ int methnum;
+ char **methods;
+
+ /*
+ * If it's a known methods, either builtin or registered
+ * by a module, use the bitmask.
+ */
+ methnum = ap_method_number_of(method);
+ l->method_mask |= ~(AP_METHOD_BIT << methnum);
+ if (methnum != M_INVALID) {
+ return;
+ }
+ /*
+ * Otherwise, see if the method name is in the array of string names.
+ */
+ if (l->method_list->nelts != 0) {
+ register int i, j, k;
+ methods = (char **)l->method_list->elts;
+ for (i = 0; i < l->method_list->nelts; ) {
+ if (strcmp(method, methods[i]) == 0) {
+ for (j = i, k = i + 1; k < l->method_list->nelts; ++j, ++k) {
+ methods[j] = methods[k];
+ }
+ --l->method_list->nelts;
+ }
+ else {
+ ++i;
+ }
+ }
+ }
+}
+
+/*
+ * Reset a method list to be completely empty.
+ */
+AP_DECLARE(void) ap_clear_method_list(ap_method_list_t *l)
+{
+ l->method_mask = 0;
+ l->method_list->nelts = 0;
+}
+
+/* Generate the human-readable hex representation of an unsigned long
+ * (basically a faster version of 'sprintf("%lx")')
+ */
+#define HEX_DIGITS "0123456789abcdef"
+static char *etag_ulong_to_hex(char *next, unsigned long u)
+{
+ int printing = 0;
+ int shift = sizeof(unsigned long) * 8 - 4;
+ do {
+ unsigned long next_digit = ((u >> shift) & (unsigned long)0xf);
+ if (next_digit) {
+ *next++ = HEX_DIGITS[next_digit];
+ printing = 1;
+ }
+ else if (printing) {
+ *next++ = HEX_DIGITS[next_digit];
+ }
+ shift -= 4;
+ } while (shift);
+ *next++ = HEX_DIGITS[u & (unsigned long)0xf];
+ return next;
+}
+
+#define ETAG_WEAK "W/"
+#define CHARS_PER_UNSIGNED_LONG (sizeof(unsigned long) * 2)
+/*
+ * Construct an entity tag (ETag) from resource information. If it's a real
+ * file, build in some of the file characteristics. If the modification time
+ * is newer than (request-time minus 1 second), mark the ETag as weak - it
+ * could be modified again in as short an interval. We rationalize the
+ * modification time we're given to keep it from being in the future.
+ */
+AP_DECLARE(char *) ap_make_etag(request_rec *r, int force_weak)
+{
+ char *weak;
+ apr_size_t weak_len;
+ char *etag;
+ char *next;
+ core_dir_config *cfg;
+ etag_components_t etag_bits;
+ etag_components_t bits_added;
+
+ cfg = (core_dir_config *)ap_get_module_config(r->per_dir_config,
+ &core_module);
+ etag_bits = (cfg->etag_bits & (~ cfg->etag_remove)) | cfg->etag_add;
+
+ /*
+ * If it's a file (or we wouldn't be here) and no ETags
+ * should be set for files, return an empty string and
+ * note it for the header-sender to ignore.
+ */
+ if (etag_bits & ETAG_NONE) {
+ apr_table_setn(r->notes, "no-etag", "omit");
+ return "";
+ }
+
+ if (etag_bits == ETAG_UNSET) {
+ etag_bits = ETAG_BACKWARD;
+ }
+ /*
+ * Make an ETag header out of various pieces of information. We use
+ * the last-modified date and, if we have a real file, the
+ * length and inode number - note that this doesn't have to match
+ * the content-length (i.e. includes), it just has to be unique
+ * for the file.
+ *
+ * If the request was made within a second of the last-modified date,
+ * we send a weak tag instead of a strong one, since it could
+ * be modified again later in the second, and the validation
+ * would be incorrect.
+ */
+ if ((r->request_time - r->mtime > (1 * APR_USEC_PER_SEC)) &&
+ !force_weak) {
+ weak = NULL;
+ weak_len = 0;
+ }
+ else {
+ weak = ETAG_WEAK;
+ weak_len = sizeof(ETAG_WEAK);
+ }
+
+ if (r->finfo.filetype != 0) {
+ /*
+ * ETag gets set to [W/]"inode-size-mtime", modulo any
+ * FileETag keywords.
+ */
+ etag = apr_palloc(r->pool, weak_len + sizeof("\"--\"") +
+ 3 * CHARS_PER_UNSIGNED_LONG + 1);
+ next = etag;
+ if (weak) {
+ while (*weak) {
+ *next++ = *weak++;
+ }
+ }
+ *next++ = '"';
+ bits_added = 0;
+ if (etag_bits & ETAG_INODE) {
+ next = etag_ulong_to_hex(next, (unsigned long)r->finfo.inode);
+ bits_added |= ETAG_INODE;
+ }
+ if (etag_bits & ETAG_SIZE) {
+ if (bits_added != 0) {
+ *next++ = '-';
+ }
+ next = etag_ulong_to_hex(next, (unsigned long)r->finfo.size);
+ bits_added |= ETAG_SIZE;
+ }
+ if (etag_bits & ETAG_MTIME) {
+ if (bits_added != 0) {
+ *next++ = '-';
+ }
+ next = etag_ulong_to_hex(next, (unsigned long)r->mtime);
+ }
+ *next++ = '"';
+ *next = '\0';
+ }
+ else {
+ /*
+ * Not a file document, so just use the mtime: [W/]"mtime"
+ */
+ etag = apr_palloc(r->pool, weak_len + sizeof("\"\"") +
+ CHARS_PER_UNSIGNED_LONG + 1);
+ next = etag;
+ if (weak) {
+ while (*weak) {
+ *next++ = *weak++;
+ }
+ }
+ *next++ = '"';
+ next = etag_ulong_to_hex(next, (unsigned long)r->mtime);
+ *next++ = '"';
+ *next = '\0';
+ }
+
+ return etag;
+}
+
+AP_DECLARE(void) ap_set_etag(request_rec *r)
+{
+ char *etag;
+ char *variant_etag, *vlv;
+ int vlv_weak;
+
+ if (!r->vlist_validator) {
+ etag = ap_make_etag(r, 0);
+
+ /* If we get a blank etag back, don't set the header. */
+ if (!etag[0]) {
+ return;
+ }
+ }
+ else {
+ /* If we have a variant list validator (vlv) due to the
+ * response being negotiated, then we create a structured
+ * entity tag which merges the variant etag with the variant
+ * list validator (vlv). This merging makes revalidation
+ * somewhat safer, ensures that caches which can deal with
+ * Vary will (eventually) be updated if the set of variants is
+ * changed, and is also a protocol requirement for transparent
+ * content negotiation.
+ */
+
+ /* if the variant list validator is weak, we make the whole
+ * structured etag weak. If we would not, then clients could
+ * have problems merging range responses if we have different
+ * variants with the same non-globally-unique strong etag.
+ */
+
+ vlv = r->vlist_validator;
+ vlv_weak = (vlv[0] == 'W');
+
+ variant_etag = ap_make_etag(r, vlv_weak);
+
+ /* If we get a blank etag back, don't append vlv and stop now. */
+ if (!variant_etag[0]) {
+ return;
+ }
+
+ /* merge variant_etag and vlv into a structured etag */
+ variant_etag[strlen(variant_etag) - 1] = '\0';
+ if (vlv_weak) {
+ vlv += 3;
+ }
+ else {
+ vlv++;
+ }
+ etag = apr_pstrcat(r->pool, variant_etag, ";", vlv, NULL);
+ }
+
+ apr_table_setn(r->headers_out, "ETag", etag);
+}
+
+static int parse_byterange(char *range, apr_off_t clength,
+ apr_off_t *start, apr_off_t *end)
+{
+ char *dash = strchr(range, '-');
+
+ if (!dash) {
+ return 0;
+ }
+
+ if ((dash == range)) {
+ /* In the form "-5" */
+ *start = clength - apr_atoi64(dash + 1);
+ *end = clength - 1;
+ }
+ else {
+ *dash = '\0';
+ dash++;
+ *start = apr_atoi64(range);
+ if (*dash) {
+ *end = apr_atoi64(dash);
+ }
+ else { /* "5-" */
+ *end = clength - 1;
+ }
+ }
+
+ if (*start < 0) {
+ *start = 0;
+ }
+
+ if (*end >= clength) {
+ *end = clength - 1;
+ }
+
+ if (*start > *end) {
+ return -1;
+ }
+
+ return (*start > 0 || *end < clength);
+}
+
+static int ap_set_byterange(request_rec *r);
+
+typedef struct byterange_ctx {
+ apr_bucket_brigade *bb;
+ int num_ranges;
+ char *boundary;
+ char *bound_head;
+} byterange_ctx;
+
+/*
+ * Here we try to be compatible with clients that want multipart/x-byteranges
+ * instead of multipart/byteranges (also see above), as per HTTP/1.1. We
+ * look for the Request-Range header (e.g. Netscape 2 and 3) as an indication
+ * that the browser supports an older protocol. We also check User-Agent
+ * for Microsoft Internet Explorer 3, which needs this as well.
+ */
+static int use_range_x(request_rec *r)
+{
+ const char *ua;
+ return (apr_table_get(r->headers_in, "Request-Range")
+ || ((ua = apr_table_get(r->headers_in, "User-Agent"))
+ && ap_strstr_c(ua, "MSIE 3")));
+}
+
+#define BYTERANGE_FMT "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT "/%" APR_OFF_T_FMT
+#define PARTITION_ERR_FMT "apr_brigade_partition() failed " \
+ "[%" APR_OFF_T_FMT ",%" APR_OFF_T_FMT "]"
+
+AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
+ apr_bucket_brigade *bb)
+{
+#define MIN_LENGTH(len1, len2) ((len1 > len2) ? len2 : len1)
+ request_rec *r = f->r;
+ conn_rec *c = r->connection;
+ byterange_ctx *ctx;
+ apr_bucket *e;
+ apr_bucket_brigade *bsend;
+ apr_off_t range_start;
+ apr_off_t range_end;
+ char *current;
+ apr_off_t clength = 0;
+ apr_status_t rv;
+ int found = 0;
+
+ /* Iterate through the brigade until reaching EOS or a bucket with
+ * unknown length. */
+ for (e = APR_BRIGADE_FIRST(bb);
+ (e != APR_BRIGADE_SENTINEL(bb) && !APR_BUCKET_IS_EOS(e)
+ && e->length != (apr_size_t)-1);
+ e = APR_BUCKET_NEXT(e)) {
+ clength += e->length;
+ }
+
+ /* Don't attempt to do byte range work if this brigade doesn't
+ * contain an EOS, or if any of the buckets has an unknown length;
+ * this avoids the cases where it is expensive to perform
+ * byteranging (i.e. may require arbitrary amounts of memory). */
+ if (!APR_BUCKET_IS_EOS(e) || clength <= 0) {
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, bb);
+ }
+
+ {
+ int num_ranges = ap_set_byterange(r);
+
+ /* We have nothing to do, get out of the way. */
+ if (num_ranges == 0) {
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, bb);
+ }
+
+ ctx = apr_pcalloc(r->pool, sizeof(*ctx));
+ ctx->num_ranges = num_ranges;
+ /* create a brigade in case we never call ap_save_brigade() */
+ ctx->bb = apr_brigade_create(r->pool, c->bucket_alloc);
+
+ if (ctx->num_ranges > 1) {
+ /* Is ap_make_content_type required here? */
+ const char *orig_ct = ap_make_content_type(r, r->content_type);
+ /* need APR_TIME_T_FMT_HEX */
+ ctx->boundary = apr_psprintf(r->pool, "%qx%lx",
+ r->request_time, (long) getpid());
+
+ ap_set_content_type(r, apr_pstrcat(r->pool, "multipart",
+ use_range_x(r) ? "/x-" : "/",
+ "byteranges; boundary=",
+ ctx->boundary, NULL));
+
+ ctx->bound_head = apr_pstrcat(r->pool,
+ CRLF "--", ctx->boundary,
+ CRLF "Content-type: ",
+ orig_ct,
+ CRLF "Content-range: bytes ",
+ NULL);
+ ap_xlate_proto_to_ascii(ctx->bound_head, strlen(ctx->bound_head));
+ }
+ }
+
+ /* this brigade holds what we will be sending */
+ bsend = apr_brigade_create(r->pool, c->bucket_alloc);
+
+ while ((current = ap_getword(r->pool, &r->range, ','))
+ && (rv = parse_byterange(current, clength, &range_start,
+ &range_end))) {
+ apr_bucket *e2;
+ apr_bucket *ec;
+
+ if (rv == -1) {
+ continue;
+ }
+
+ /* these calls to apr_brigade_partition() should theoretically
+ * never fail because of the above call to apr_brigade_length(),
+ * but what the heck, we'll check for an error anyway */
+ if ((rv = apr_brigade_partition(bb, range_start, &ec)) != APR_SUCCESS) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
+ PARTITION_ERR_FMT, range_start, clength);
+ continue;
+ }
+ if ((rv = apr_brigade_partition(bb, range_end+1, &e2)) != APR_SUCCESS) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r,
+ PARTITION_ERR_FMT, range_end+1, clength);
+ continue;
+ }
+
+ found = 1;
+
+ /* For single range requests, we must produce Content-Range header.
+ * Otherwise, we need to produce the multipart boundaries.
+ */
+ if (ctx->num_ranges == 1) {
+ apr_table_setn(r->headers_out, "Content-Range",
+ apr_psprintf(r->pool, "bytes " BYTERANGE_FMT,
+ range_start, range_end, clength));
+ }
+ else {
+ char *ts;
+
+ e = apr_bucket_pool_create(ctx->bound_head, strlen(ctx->bound_head),
+ r->pool, c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+
+ ts = apr_psprintf(r->pool, BYTERANGE_FMT CRLF CRLF,
+ range_start, range_end, clength);
+ ap_xlate_proto_to_ascii(ts, strlen(ts));
+ e = apr_bucket_pool_create(ts, strlen(ts), r->pool,
+ c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+ }
+
+ do {
+ apr_bucket *foo;
+ const char *str;
+ apr_size_t len;
+
+ if (apr_bucket_copy(ec, &foo) != APR_SUCCESS) {
+ /* this shouldn't ever happen due to the call to
+ * apr_brigade_length() above which normalizes
+ * indeterminate-length buckets. just to be sure,
+ * though, this takes care of uncopyable buckets that
+ * do somehow manage to slip through.
+ */
+ /* XXX: check for failure? */
+ apr_bucket_read(ec, &str, &len, APR_BLOCK_READ);
+ apr_bucket_copy(ec, &foo);
+ }
+ APR_BRIGADE_INSERT_TAIL(bsend, foo);
+ ec = APR_BUCKET_NEXT(ec);
+ } while (ec != e2);
+ }
+
+ if (found == 0) {
+ ap_remove_output_filter(f);
+ r->status = HTTP_OK;
+ /* bsend is assumed to be empty if we get here. */
+ e = ap_bucket_error_create(HTTP_RANGE_NOT_SATISFIABLE, NULL,
+ r->pool, c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+ e = apr_bucket_eos_create(c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+ return ap_pass_brigade(f->next, bsend);
+ }
+
+ if (ctx->num_ranges > 1) {
+ char *end;
+
+ /* add the final boundary */
+ end = apr_pstrcat(r->pool, CRLF "--", ctx->boundary, "--" CRLF, NULL);
+ ap_xlate_proto_to_ascii(end, strlen(end));
+ e = apr_bucket_pool_create(end, strlen(end), r->pool, c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+ }
+
+ e = apr_bucket_eos_create(c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bsend, e);
+
+ /* we're done with the original content - all of our data is in bsend. */
+ apr_brigade_destroy(bb);
+
+ /* send our multipart output */
+ return ap_pass_brigade(f->next, bsend);
+}
+
+static int ap_set_byterange(request_rec *r)
+{
+ const char *range;
+ const char *if_range;
+ const char *match;
+ const char *ct;
+ int num_ranges;
+
+ if (r->assbackwards) {
+ return 0;
+ }
+
+ /* Check for Range request-header (HTTP/1.1) or Request-Range for
+ * backwards-compatibility with second-draft Luotonen/Franks
+ * byte-ranges (e.g. Netscape Navigator 2-3).
+ *
+ * We support this form, with Request-Range, and (farther down) we
+ * send multipart/x-byteranges instead of multipart/byteranges for
+ * Request-Range based requests to work around a bug in Netscape
+ * Navigator 2-3 and MSIE 3.
+ */
+
+ if (!(range = apr_table_get(r->headers_in, "Range"))) {
+ range = apr_table_get(r->headers_in, "Request-Range");
+ }
+
+ if (!range || strncasecmp(range, "bytes=", 6) || r->status != HTTP_OK) {
+ return 0;
+ }
+
+ /* is content already a single range? */
+ if (apr_table_get(r->headers_out, "Content-Range")) {
+ return 0;
+ }
+
+ /* is content already a multiple range? */
+ if ((ct = apr_table_get(r->headers_out, "Content-Type"))
+ && (!strncasecmp(ct, "multipart/byteranges", 20)
+ || !strncasecmp(ct, "multipart/x-byteranges", 22))) {
+ return 0;
+ }
+
+ /* Check the If-Range header for Etag or Date.
+ * Note that this check will return false (as required) if either
+ * of the two etags are weak.
+ */
+ if ((if_range = apr_table_get(r->headers_in, "If-Range"))) {
+ if (if_range[0] == '"') {
+ if (!(match = apr_table_get(r->headers_out, "Etag"))
+ || (strcmp(if_range, match) != 0)) {
+ return 0;
+ }
+ }
+ else if (!(match = apr_table_get(r->headers_out, "Last-Modified"))
+ || (strcmp(if_range, match) != 0)) {
+ return 0;
+ }
+ }
+
+ if (!ap_strchr_c(range, ',')) {
+ /* a single range */
+ num_ranges = 1;
+ }
+ else {
+ /* a multiple range */
+ num_ranges = 2;
+ }
+
+ r->status = HTTP_PARTIAL_CONTENT;
+ r->range = range + 6;
+
+ return num_ranges;
+}