/* 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. */ /* * Originally written @ BBC by Graham Leggett * (C) 2011 British Broadcasting Corporation */ /* * mod_policy.c --- Enforce specific policies on outgoing requests, logging * or rejecting requests as appropriate. * * To enable, add the corresponding filters like so: * * SetOutputFilter POLICY_TYPE,POLICY_LENGTH * */ #include "util_filter.h" #include "httpd.h" #include "http_config.h" #include "http_core.h" #include "http_log.h" #include "http_protocol.h" #include "apr_tables.h" #include "apr_strings.h" #include "apr_date.h" module AP_MODULE_DECLARE_DATA policy_module; #define POLICY_DEFAULT_TYPE "*/*" typedef enum policy_result { policy_ignore = 0, /* ignore this policy */ policy_log, /* log the violation as a warning, but let it through */ policy_enforce /* log the violation as an error, and decline */ } policy_result; typedef struct policy_conf { int policy; /* whether the filters should do anything at all */ int policy_set; const char *environment; /* optional name of the subprocess environment variable that * controls whether the policies are enforced. */ const char *environment_log; /* value to trigger logging only */ const char *environment_ignore; /* value to suspend policy enforcement */ int environment_set; policy_result type_action; apr_array_header_t *type_matches; /* content type default patterns to match */ int type_set; const char *type_url; int type_url_set; policy_result length_action; int length_set; const char *length_url; int length_url_set; policy_result keepalive_action; int keepalive_set; const char *keepalive_url; int keepalive_url_set; policy_result vary_action; apr_array_header_t *vary_matches; /* Vary default patterns to match */ int vary_set; const char *vary_url; int vary_url_set; policy_result validation_action; int validation_set; const char *validation_url; int validation_url_set; policy_result conditional_action; int conditional_set; const char *conditional_url; int conditional_url_set; policy_result nocache_action; int nocache_set; const char *nocache_url; int nocache_url_set; policy_result maxage_action; apr_int64_t maxage; int maxage_set; const char *maxage_url; int maxage_url_set; policy_result version_action; const char *version; int version_num; int version_set; const char *version_url; int version_url_set; } policy_conf; /** * Does the value of a flagpole override the original value? */ static int check_enabled(request_rec *r, policy_conf *conf, policy_result result) { if (conf && !conf->policy) { return policy_ignore; } if (conf && result != policy_ignore && conf->environment) { const char *value = apr_table_get(r->subprocess_env, conf->environment); if (value) { /* downgrade enforce to log? */ if (conf->environment_log && !strcmp(value, conf->environment_log)) { if (result == policy_enforce) { return policy_log; } } /* downgrade enforce and log to ignore? */ else if (conf->environment_ignore && !strcmp(value, conf->environment_ignore)) { return policy_ignore; } } } return result; } static void handle_policy(request_rec *r, policy_result result, const char *message, const char *url, apr_bucket_brigade *bb, int status) { apr_bucket *e; switch (result) { case policy_log: { ap_log_rerror( APLOG_MARK, APLOG_WARNING, 0, r, "mod_policy: violation: %s, uri: %s", message, r->uri); apr_table_addn(r->headers_out, "Warning", apr_psprintf(r->pool, "299 %s \"%s\"", ap_get_server_name(r), message)); break; } case policy_enforce: { ap_log_rerror( APLOG_MARK, APLOG_ERR, 0, r, "mod_policy: violation, rejecting request: %s, uri: %s", message, r->uri); apr_table_addn(r->err_headers_out, "Warning", apr_psprintf(r->pool, "299 %s \"Rejected: %s\"", ap_get_server_name(r), message)); apr_table_setn( r->notes, "error-notes", apr_pstrcat(r->pool, url ? apr_pstrcat(r->pool, "", NULL) : "", message, url ? "" : "", NULL)); apr_brigade_cleanup(bb); e = ap_bucket_error_create(status, NULL, r->pool, r->connection->bucket_alloc); APR_BRIGADE_INSERT_TAIL(bb, e); e = apr_bucket_eos_create(r->connection->bucket_alloc); APR_BRIGADE_INSERT_TAIL(bb, e); } case policy_ignore: { } } } /** * Policy for Content-Type. * * - It must be present. * - It must match the optional regex (default .* / .*) */ static apr_status_t policy_type_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->type_action); if (result != policy_ignore) { int fail = 1; /* content type present and valid? */ if (f->r->content_type) { const char *type = f->r->content_type; const char *end = ap_strchr_c(type, ';'); if (end) { type = apr_pstrmemdup(f->r->pool, type, end - type); } if (!conf->type_matches) { if (!ap_strcmp_match(type, POLICY_DEFAULT_TYPE)) { fail = 0; } } else { int i; for (i = 0; i < conf->type_matches->nelts; i++) { if (!ap_strcmp_match(type, ((char **) conf->type_matches->elts)[i])) { fail = 0; break; } } } } if (fail) { const char *types = NULL; if (conf->type_matches) { int i; for (i = 0; i < conf->type_matches->nelts; i++) { types = apr_pstrcat(f->r->pool, types ? ", " : "", ((char **) conf->type_matches->elts)[i], NULL); } } else { types = POLICY_DEFAULT_TYPE; } handle_policy( f->r, result, apr_psprintf( f->r->pool, "Content-Type of '%s' should be RFC compliant and match one of: %s", f->r->content_type, types), conf->type_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for Content-Length. * * - It must be present (missing, or Transfer-Encoding: chunked would be rejected) * - Only applies to 2xx result codes */ static apr_status_t policy_length_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { request_rec *r = f->r; policy_conf *conf = ap_get_module_config(r->per_dir_config, &policy_module); policy_result result = check_enabled(r, conf, conf->length_action); if (result != policy_ignore && r->status >= 200 && r->status < 300 && r->status != HTTP_NO_CONTENT) { if (!apr_table_get(r->headers_out, "Content-Length")) { handle_policy(r, result, "Content-Length should be present", conf->length_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for Content-Length / Chunked Encoding. * * We follow a subset of the algorithm httpd uses, which is: * * IF we have not marked this connection as errored; * and the client isn't expecting 100-continue (PR47087 - more * input here could be the client continuing when we're * closing the request). * and the response status does not require a close; * 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 * THEN we support keepalive. * * Note: The server may choose to turn off keepalive for various reasons, * such as an imminent shutdown, or a Connection: close from the client, * but for our purposes we only care that keepalive was possible from * the application, not that keepalive actually took place. */ static apr_status_t policy_keepalive_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { request_rec *r = f->r; policy_conf *conf = ap_get_module_config(r->per_dir_config, &policy_module); policy_result result = check_enabled(r, conf, conf->keepalive_action); if (result != policy_ignore && r->connection->keepalive != AP_CONN_CLOSE && !r->expecting_100 && !ap_status_drops_connection(r->status)) { if (!((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))) { handle_policy(r, result, "Keepalive should be possible (supply Content-Length or HTTP/1.1 Transfer-Encoding)", conf->keepalive_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } static int vary_test(void *rec, const char *key, const char *value) { request_rec *r = (request_rec *)rec; char *token = apr_pstrdup(r->pool, value); char *last; policy_conf *conf = ap_get_module_config(r->per_dir_config, &policy_module); token = apr_strtok(token, ", \t", &last); while (token) { int i; for (i = 0; i < conf->vary_matches->nelts; i++) { if (!ap_strcasecmp_match(token, ((char **) conf->vary_matches->elts)[i])) { return 0; } } token = apr_strtok(NULL, ", \t", &last); } return 1; } /** * Policy for Vary. * * - If an element matches the optional regex (no default), the request is rejected. * Typically used to reject Varying on User-Agent. */ static apr_status_t policy_vary_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->vary_action); if (result != policy_ignore) { /* Vary present and valid? */ if (!apr_table_do(vary_test, f->r, f->r->headers_out, "Vary", NULL)) { const char *varys = NULL; if (conf->vary_matches) { int i; for (i = 0; i < conf->vary_matches->nelts; i++) { varys = apr_pstrcat(f->r->pool, varys ? ", " : "", ((char **) conf->vary_matches->elts)[i], NULL); } } handle_policy(f->r, result, apr_psprintf(f->r->pool, "Vary header(s) should NOT match any of: %s", varys), conf->vary_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for Validation. * * Validation is possible through either the ETag or Last-Modified header, as described * in http://www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.3. * * - Either must be present * - Last-Modified, if present, must parse to a valid date * - ETag, if present, must parse to a valid ETag. */ static apr_status_t policy_validation_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->validation_action); if (result != policy_ignore) { int fail = 1, etagfail = 0, lmfail = 0; const char *etag = apr_table_get(f->r->headers_out, "ETag"); const char *lastmodified = apr_table_get(f->r->headers_out, "Last-Modified"); if (etag) { int len = strlen(etag); if (len > 1) { if (etag[0] == '\"' && etag[len - 1] == '\"') { fail = 0; } else if (etag[0] == 'W' && etag[1] == '/' && etag[2] == '\"' && etag[len - 1] == '\"') { fail = 0; } } if (fail) { etagfail = 1; } } if (lastmodified) { apr_time_t lastmod = apr_date_parse_http(lastmodified); if (lastmod != APR_DATE_BAD) { fail = 0; } if (fail) { lmfail = 1; } } if (fail) { const char *error = NULL; if (!etag && !lastmodified) { error = apr_psprintf(f->r->pool, "Etag and Last Modified missing"); } else { error = apr_pstrcat(f->r->pool, (etagfail ? "ETag syntax error (check quotes)" : ""), (etagfail && lmfail ? " / " : ""), (lmfail ? "Last-Modified could not be parsed" : ""), NULL); } handle_policy(f->r, result, error, conf->validation_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for Revalidation through Conditional Requests. * * The If-None-Match header is described in * http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26. Over and above the * checks done in the validation filter, the conditional filter detects when an * If-None-Match header is present in the request, an ETag is present in the response, * and the response code is unexpected given the match. A result code is unexpected * where a 304 Not Modified or 412 Precondition Failed was expected, but a 200 response * was seen instead. */ static apr_status_t policy_conditional_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->conditional_action); if (result != policy_ignore) { int code = ap_meets_conditions(f->r); if (OK != code && code != f->r->status) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Conditional request should have returned %d, instead returned %d", code, f->r->status), conf->conditional_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for No-Cache Requests. * * If the Cache-Control and/or Pragma header specifies that the content is not * cacheable, the request will be rejected. * * - If Cache-Control: no-cache * - If Pragma: no-cache * - If Cache-Control: no-store * - If Cache-Control: private */ static apr_status_t policy_nocache_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->nocache_action); if (result != policy_ignore) { request_rec *r = f->r; const char *cc_header = apr_table_get(r->headers_out, "Cache-Control"); const char *pragma_header = apr_table_get(r->headers_out, "Pragma"); int fail = 0; char *last; if (pragma_header) { char *header = apr_pstrdup(r->pool, pragma_header); const char *token = apr_strtok(header, ", ", &last); while (token) { /* handle most common quickest case... */ if (!strcmp(token, "no-cache")) { fail = 1; } /* ...then try slowest case */ else if (!strcasecmp(token, "no-cache")) { fail = 1; } token = apr_strtok(NULL, ", ", &last); } } if (cc_header) { char *header = apr_pstrdup(r->pool, cc_header); const char *token = apr_strtok(header, ", ", &last); while (token) { switch (token[0]) { case 'n': case 'N': { /* handle most common quickest cases... */ if (!strcmp(token, "no-cache")) { fail = 1; } else if (!strcmp(token, "no-store")) { fail = 1; } /* ...then try slowest cases */ else if (!strncasecmp(token, "no-cache", 8)) { if (token[8] == '=') { } else if (!token[8]) { fail = 1; } break; } else if (!strcasecmp(token, "no-store")) { fail = 1; } break; } case 'p': case 'P': { /* handle most common quickest cases... */ if (!strcmp(token, "private")) { fail = 1; } /* ...then try slowest cases */ else if (!strncasecmp(token, "private", 7)) { if (token[7] == '=') { } else if (!token[7]) { fail = 1; } break; } break; } } token = apr_strtok(NULL, ", ", &last); } } if (fail) { handle_policy(r, result, "Response is marked uncacheable", conf->nocache_url, bb, HTTP_BAD_GATEWAY); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /** * Policy for Maxage. * * If the effective maxage of the request is less than the parameter provided, * the request will be rejected. * * - If Cache-Control: s-maxage is less than the limit * - If Cache-Control: maxage is less than the limit * - If Expires - Date is less than the limit * - If none of the above, reject the request, as maxage is heuristic * * As soon as a test passes, we stop, as HTTP maxage handling follows a given * set of priorities (s-maxage beats maxage, maxage beats Expires). */ static apr_status_t policy_maxage_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { policy_conf *conf = ap_get_module_config(f->r->per_dir_config, &policy_module); policy_result result = check_enabled(f->r, conf, conf->maxage_action); if (result != policy_ignore) { request_rec *r = f->r; const char *cc_header; const char *expires_header; const char *date_header; char *last; int max_age = 0; apr_int64_t max_age_value = 0; int s_maxage = 0; apr_int64_t s_maxage_value = 0; /* parse Cache-Control */ cc_header = apr_table_get(r->headers_out, "Cache-Control"); if (cc_header) { char *header = apr_pstrdup(r->pool, cc_header); const char *token = apr_strtok(header, ", ", &last); while (token) { switch (token[0]) { case 'm': case 'M': { /* handle most common quickest cases... */ if (!strncmp(token, "max-age", 7)) { max_age = 1; max_age_value = apr_atoi64(token + 8); } /* ...then try slowest cases */ else if (!strncasecmp(token, "max-age", 7)) { if (token[7] == '=') { max_age = 1; max_age_value = apr_atoi64(token + 8); } break; } break; } case 's': case 'S': { if (!strncmp(token, "s-maxage", 8)) { if (token[8] == '=') { s_maxage = 1; s_maxage_value = apr_atoi64(token + 9); } break; } else if (!strncasecmp(token, "s-maxage", 8)) { if (token[8] == '=') { s_maxage = 1; s_maxage_value = apr_atoi64(token + 9); } break; } break; } } token = apr_strtok(NULL, ", ", &last); } } /* test s-maxage, if present */ if (s_maxage) { if (s_maxage_value < conf->maxage) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Response s-maxage of %" APR_INT64_T_FMT " must be at least %" APR_INT64_T_FMT, s_maxage_value, conf->maxage), conf->maxage_url, bb, HTTP_BAD_GATEWAY); } /* decision is made, leave */ ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /* test max-age, if present */ if (max_age) { if (max_age_value < conf->maxage) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Response max-age of %" APR_INT64_T_FMT " must be at least %" APR_INT64_T_FMT, max_age_value, conf->maxage), conf->maxage_url, bb, HTTP_BAD_GATEWAY); } /* decision is made, leave */ ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /* test expires, if present */ expires_header = apr_table_get(r->headers_out, "Expires"); date_header = apr_table_get(r->headers_out, "Date"); if (expires_header && date_header) { apr_time_t expires = apr_date_parse_http(expires_header); apr_time_t date = apr_date_parse_http(date_header); apr_int64_t fresh = apr_time_sec(expires - date); if (expires == APR_DATE_BAD) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Response Expires of '%s' is invalid, maxage %" APR_INT64_T_FMT " required", expires_header, conf->maxage), conf->maxage_url, bb, HTTP_BAD_GATEWAY); } else if (date == APR_DATE_BAD) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Response Date of '%s' is invalid, maxage %" APR_INT64_T_FMT " required", date_header, conf->maxage), conf->maxage_url, bb, HTTP_BAD_GATEWAY); } else if (conf->maxage > 0 && fresh < conf->maxage) { handle_policy( f->r, result, apr_psprintf( f->r->pool, "Response expires in %" APR_INT64_T_FMT " seconds, must be at least %" APR_INT64_T_FMT, fresh, conf->maxage), conf->maxage_url, bb, HTTP_BAD_GATEWAY); } /* decision is made, leave */ ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } /* no explicit maxage defined, so fail */ handle_policy(r, result, "Response has no explicit freshness lifetime (s-maxage, max-age or Expires/Date)", conf->maxage_url, bb, HTTP_BAD_GATEWAY); } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } static const char *version_string(int proto_num) { switch (proto_num) { case HTTP_VERSION(0, 9): { return "HTTP/0.9"; } case HTTP_VERSION(1, 0): { return "HTTP/1.0"; } case HTTP_VERSION(1, 1): { return "HTTP/1.1"; } default: { return "(unknown)"; } } } /** * Policy for HTTP Version. * * - The HTTP version of the response must be at least the level specified. */ static apr_status_t policy_version_out_filter(ap_filter_t *f, apr_bucket_brigade *bb) { request_rec *r = f->r; policy_conf *conf = ap_get_module_config(r->per_dir_config, &policy_module); policy_result result = check_enabled(r, conf, conf->version_action); if (result != policy_ignore) { if (r->proto_num > 0 && r->proto_num < conf->version_num) { handle_policy(f->r, result, apr_psprintf(f->r->pool, "Request HTTP version '%s' should be at least '%s'", version_string(r->proto_num), conf->version), conf->version_url, bb, HTTP_VERSION_NOT_SUPPORTED); } } ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } static void *create_policy_config(apr_pool_t *p, char *dummy) { policy_conf *new = (policy_conf *) apr_pcalloc(p, sizeof(policy_conf)); new->policy = 1; new->type_action = policy_log; new->length_action = policy_log; new->vary_action = policy_log; new->validation_action = policy_log; new->conditional_action = policy_log; new->nocache_action = policy_log; new->maxage_action = policy_log; new->version_action = policy_log; new->version_num = HTTP_VERSION(0, 9); new->version = "HTTP/0.9"; return (void *) new; } static void *merge_policy_config(apr_pool_t *p, void *basev, void *addv) { policy_conf *new = (policy_conf *) apr_pcalloc(p, sizeof(policy_conf)); policy_conf *add = (policy_conf *) addv; policy_conf *base = (policy_conf *) basev; new->policy = (add->policy_set == 0) ? base->policy : add->policy; new->policy_set = add->policy_set || base->policy_set; new->environment = (add->environment_set == 0) ? base->environment : add->environment; new->environment_log = (add->environment_set == 0) ? base->environment_log : add->environment_log; new->environment_ignore = (add->environment_set == 0) ? base->environment_ignore : add->environment_ignore; new->environment_set = add->environment_set || base->environment_set; new->type_action = (add->type_set == 0) ? base->type_action : add->type_action; new->type_matches = (add->type_set == 0) ? base->type_matches : add->type_matches; new->type_set = add->type_set || base->type_set; new->type_url = (add->type_url_set == 0) ? base->type_url : add->type_url; new->type_url_set = add->type_url_set || base->type_url_set; new->length_action = (add->length_set == 0) ? base->length_action : add->length_action; new->length_set = add->length_set || base->length_set; new->length_url = (add->length_url_set == 0) ? base->length_url : add->length_url; new->length_url_set = add->length_url_set || base->length_url_set; new->vary_action = (add->vary_set == 0) ? base->vary_action : add->vary_action; new->vary_matches = (add->vary_set == 0) ? base->vary_matches : add->vary_matches; new->vary_set = add->vary_set || base->vary_set; new->vary_url = (add->vary_url_set == 0) ? base->vary_url : add->vary_url; new->vary_url_set = add->vary_url_set || base->vary_url_set; new->validation_action = (add->validation_set == 0) ? base->validation_action : add->validation_action; new->validation_set = add->validation_set || base->validation_set; new->validation_url = (add->validation_url_set == 0) ? base->validation_url : add->validation_url; new->validation_url_set = add->validation_url_set || base->validation_url_set; new->conditional_action = (add->conditional_set == 0) ? base->conditional_action : add->conditional_action; new->conditional_set = add->conditional_set || base->conditional_set; new->conditional_url = (add->conditional_url_set == 0) ? base->conditional_url : add->conditional_url; new->conditional_url_set = add->conditional_url_set || base->conditional_url_set; new->nocache_action = (add->nocache_set == 0) ? base->nocache_action : add->nocache_action; new->nocache_set = add->nocache_set || base->nocache_set; new->nocache_url = (add->nocache_url_set == 0) ? base->nocache_url : add->nocache_url; new->nocache_url_set = add->nocache_url_set || base->nocache_url_set; new->maxage_action = (add->maxage_set == 0) ? base->maxage_action : add->maxage_action; new->maxage = (add->maxage_set == 0) ? base->maxage : add->maxage; new->maxage_set = add->maxage_set || base->maxage_set; new->maxage_url = (add->maxage_url_set == 0) ? base->maxage_url : add->maxage_url; new->maxage_url_set = add->maxage_url_set || base->maxage_url_set; new->version_action = (add->version_set == 0) ? base->version_action : add->version_action; new->version = (add->version_set == 0) ? base->version : add->version; new->version_num = (add->version_set == 0) ? base->version_num : add->version_num; new->version_set = add->version_set || base->version_set; new->version_url = (add->version_url_set == 0) ? base->version_url : add->version_url; new->version_url_set = add->version_url_set || base->version_url_set; return new; } static const char *parse_action(apr_pool_t *pool, const char *action, policy_result *result) { if (!strcmp(action, "enforce")) { *result = policy_enforce; } else if (!strcmp(action, "log")) { *result = policy_log; } else if (!strcmp(action, "ignore")) { *result = policy_ignore; } else { return apr_psprintf(pool, "'%s' must be one of 'enforce, 'log' or 'ignore'.", action); } return NULL; } static const char *set_policy(cmd_parms *cmd, void *dconf, int flag) { policy_conf *conf = dconf; conf->policy = flag; conf->policy_set = 1; return NULL; } static const char *set_environment(cmd_parms *cmd, void *dconf, const char *environment, const char *log, const char *ignore) { policy_conf *conf = dconf; conf->environment = environment; conf->environment_log = log; conf->environment_ignore = ignore; conf->environment_set = 1; return NULL; } static const char *set_type(cmd_parms *cmd, void *dconf, const char *action, const char *type) { policy_conf *conf = dconf; if (type) { const char **match_ptr; if (!conf->type_matches) { conf->type_matches = apr_array_make(cmd->pool, 2, sizeof(const char *)); } match_ptr = apr_array_push(conf->type_matches); *match_ptr = type; } conf->type_set = 1; return parse_action(cmd->pool, action, &conf->type_action); } static const char *set_type_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->type_url = url; conf->type_url_set = 1; return NULL; } static const char *set_length(cmd_parms *cmd, void *dconf, const char *action) { policy_conf *conf = dconf; conf->length_set = 1; return parse_action(cmd->pool, action, &conf->length_action); } static const char *set_length_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->length_url = url; conf->length_url_set = 1; return NULL; } static const char *set_keepalive(cmd_parms *cmd, void *dconf, const char *action) { policy_conf *conf = dconf; conf->keepalive_set = 1; return parse_action(cmd->pool, action, &conf->keepalive_action); } static const char *set_keepalive_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->keepalive_url = url; conf->keepalive_url_set = 1; return NULL; } static const char *set_vary(cmd_parms *cmd, void *dconf, const char *action, const char *vary) { policy_conf *conf = dconf; if (vary) { const char **match_ptr; if (!conf->vary_matches) { conf->vary_matches = apr_array_make(cmd->pool, 2, sizeof(const char *)); } match_ptr = apr_array_push(conf->vary_matches); *match_ptr = vary; } conf->vary_set = 1; return parse_action(cmd->pool, action, &conf->vary_action); } static const char *set_vary_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->vary_url = url; conf->vary_url_set = 1; return NULL; } static const char *set_validation(cmd_parms *cmd, void *dconf, const char *action) { policy_conf *conf = dconf; conf->validation_set = 1; return parse_action(cmd->pool, action, &conf->validation_action); } static const char *set_validation_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->validation_url = url; conf->validation_url_set = 1; return NULL; } static const char *set_conditional(cmd_parms *cmd, void *dconf, const char *action) { policy_conf *conf = dconf; conf->conditional_set = 1; return parse_action(cmd->pool, action, &conf->conditional_action); } static const char *set_conditional_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->conditional_url = url; conf->conditional_url_set = 1; return NULL; } static const char *set_nocache(cmd_parms *cmd, void *dconf, const char *action) { policy_conf *conf = dconf; conf->nocache_set = 1; return parse_action(cmd->pool, action, &conf->nocache_action); } static const char *set_nocache_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->nocache_url = url; conf->nocache_url_set = 1; return NULL; } static const char *set_maxage(cmd_parms *cmd, void *dconf, const char *action, const char *maxage) { policy_conf *conf = dconf; conf->maxage_set = 1; conf->maxage = apr_atoi64(maxage); if (conf->maxage < 0) { return apr_psprintf(cmd->pool, "'%s' must be a positive integer.", maxage); } return parse_action(cmd->pool, action, &conf->maxage_action); } static const char *set_maxage_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->maxage_url = url; conf->maxage_url_set = 1; return NULL; } static const char *set_version(cmd_parms *cmd, void *dconf, const char *action, const char *version) { policy_conf *conf = dconf; conf->version_set = 1; if (!strcmp(version, "HTTP/1.1")) { conf->version = "HTTP/1.1"; conf->version_num = HTTP_VERSION(1, 1); } else if (!strcmp(version, "HTTP/1.0")) { conf->version = "HTTP/1.0"; conf->version_num = HTTP_VERSION(1, 0); } else if (!strcmp(version, "HTTP/0.9")) { conf->version = "HTTP/0.9"; conf->version_num = HTTP_VERSION(0, 9); } else { return apr_psprintf(cmd->pool, "'%s' must be one of 'HTTP/1.1', 'HTTP/1.0' or 'HTTP/0.9'.", version); } return parse_action(cmd->pool, action, &conf->version_action); } static const char *set_version_url(cmd_parms *cmd, void *dconf, const char *url) { policy_conf *conf = dconf; conf->version_url = url; conf->version_url_set = 1; return NULL; } static const command_rec policy_cmds[] = { AP_INIT_FLAG("PolicyFilter", set_policy, NULL, RSRC_CONF | ACCESS_CONF, "Whether policies should be applied. Defaults to 'on'."), AP_INIT_TAKE1( "PolicyConditional", set_conditional, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if a conditional request was not honoured. Defaults to 'log'."), AP_INIT_TAKE1("PolicyConditionalURL", set_conditional_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the conditional request policy."), AP_INIT_TAKE3( "PolicyEnvironment", set_environment, NULL, RSRC_CONF | ACCESS_CONF, "Environment variable to control policy enforcement, followed by the variable value for logging only, and the value for policy suspension."), AP_INIT_TAKE1( "PolicyLength", set_length, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if Content-Length missing. Defaults to 'log'."), AP_INIT_TAKE1("PolicyLengthURL", set_length_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the content length policy."), AP_INIT_TAKE1( "PolicyKeepalive", set_keepalive, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if keepalive is not possible. Defaults to 'log'."), AP_INIT_TAKE1("PolicyKeepaliveURL", set_keepalive_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the keepalive policy."), AP_INIT_ITERATE2( "PolicyType", set_type, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log), followed by one or more valid content types containing optional wildcards ? and *"), AP_INIT_TAKE1("PolicyTypeURL", set_type_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the content type policy."), AP_INIT_ITERATE2( "PolicyVary", set_vary, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log), followed by one or more headers containing optional wildcards ? and * that are NOT to appear in a Vary header"), AP_INIT_TAKE1("PolicyVaryURL", set_vary_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the vary header policy."), AP_INIT_TAKE1( "PolicyValidation", set_validation, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if Last-Modified or Etag is missing or invalid. Defaults to 'log'."), AP_INIT_TAKE1("PolicyValidationURL", set_validation_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the content validation policy."), AP_INIT_TAKE1( "PolicyNocache", set_nocache, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if a response is not cacheable. Defaults to 'log'."), AP_INIT_TAKE1("PolicyNocacheURL", set_nocache_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the no cache policy."), AP_INIT_TAKE2( "PolicyMaxage", set_maxage, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if a response has an effective maxage less than the age provided. Defaults to 'log'."), AP_INIT_TAKE1("PolicyMaxageURL", set_maxage_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the maxage policy."), AP_INIT_TAKE2( "PolicyVersion", set_version, NULL, RSRC_CONF | ACCESS_CONF, "Action to take (enforce, ignore, log) if a response has an HTTP version less than the version provided. Defaults to 'log HTTP/0.9'."), AP_INIT_TAKE1("PolicyVersionURL", set_version_url, NULL, RSRC_CONF | ACCESS_CONF, "URL describing the version policy."), { NULL } }; static void register_hooks(apr_pool_t *p) { ap_register_output_filter("POLICY_TYPE", policy_type_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_LENGTH", policy_length_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_KEEPALIVE", policy_keepalive_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_VARY", policy_vary_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_VALIDATION", policy_validation_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_CONDITIONAL", policy_conditional_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_NOCACHE", policy_nocache_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_MAXAGE", policy_maxage_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); ap_register_output_filter("POLICY_VERSION", policy_version_out_filter, NULL, AP_FTYPE_CONTENT_SET + 5); } AP_DECLARE_MODULE(policy) = { STANDARD20_MODULE_STUFF, create_policy_config, /* create per-directory config structure */ merge_policy_config, /* merge per-directory config structures */ NULL, /* create per-server config structure */ NULL, /* merge per-server config structures */ policy_cmds, /* command apr_table_t */ register_hooks /* register hooks */ };