/* 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, APLOGNO(03041)
"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, APLOGNO(03042)
"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",
url ? apr_pstrcat(r->pool, "",
message, "", NULL)
: message);
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) {
if (!ap_cstr_casecmp(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': {
if (!ap_cstr_casecmpn(token, "no-cache", 8)) {
if (token[8] == '=') {
}
else if (!token[8]) {
fail = 1;
}
break;
}
else if (!ap_cstr_casecmp(token, "no-store")) {
fail = 1;
}
break;
}
case 'p':
case 'P': {
if (!ap_cstr_casecmpn(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': {
if (!ap_cstr_casecmpn(token, "max-age", 7)) {
if (token[7] == '=') {
max_age = 1;
max_age_value = apr_atoi64(token + 8);
}
break;
}
break;
}
case 's':
case 'S': {
if (!ap_cstr_casecmpn(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;
/* url is only used inside , escape accordingly */
conf->type_url = ap_escape_html(cmd->pool, 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 */
};