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-rw-r--r--modules/session/mod_session.c711
1 files changed, 711 insertions, 0 deletions
diff --git a/modules/session/mod_session.c b/modules/session/mod_session.c
new file mode 100644
index 0000000..fa8d406
--- /dev/null
+++ b/modules/session/mod_session.c
@@ -0,0 +1,711 @@
+/* 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.
+ */
+
+#include "mod_session.h"
+#include "apr_lib.h"
+#include "apr_strings.h"
+#include "util_filter.h"
+#include "http_log.h"
+#include "http_request.h"
+#include "http_protocol.h"
+
+#define SESSION_EXPIRY "expiry"
+#define HTTP_SESSION "HTTP_SESSION"
+
+APR_HOOK_STRUCT(
+ APR_HOOK_LINK(session_load)
+ APR_HOOK_LINK(session_save)
+ APR_HOOK_LINK(session_encode)
+ APR_HOOK_LINK(session_decode)
+)
+APR_IMPLEMENT_EXTERNAL_HOOK_RUN_FIRST(ap, SESSION, int, session_load,
+ (request_rec * r, session_rec ** z), (r, z), DECLINED)
+APR_IMPLEMENT_EXTERNAL_HOOK_RUN_FIRST(ap, SESSION, int, session_save,
+ (request_rec * r, session_rec * z), (r, z), DECLINED)
+APR_IMPLEMENT_EXTERNAL_HOOK_RUN_ALL(ap, SESSION, int, session_encode,
+ (request_rec * r, session_rec * z), (r, z), OK, DECLINED)
+APR_IMPLEMENT_EXTERNAL_HOOK_RUN_ALL(ap, SESSION, int, session_decode,
+ (request_rec * r, session_rec * z), (r, z), OK, DECLINED)
+
+static int session_identity_encode(request_rec * r, session_rec * z);
+static int session_identity_decode(request_rec * r, session_rec * z);
+static int session_fixups(request_rec * r);
+
+/**
+ * Should the session be included within this URL.
+ *
+ * This function tests whether a session is valid for this URL. It uses the
+ * include and exclude arrays to determine whether they should be included.
+ */
+static int session_included(request_rec * r, session_dir_conf * conf)
+{
+
+ const char **includes = (const char **) conf->includes->elts;
+ const char **excludes = (const char **) conf->excludes->elts;
+ int included = 1; /* defaults to included */
+ int i;
+
+ if (conf->includes->nelts) {
+ included = 0;
+ for (i = 0; !included && i < conf->includes->nelts; i++) {
+ const char *include = includes[i];
+ if (strncmp(r->uri, include, strlen(include)) == 0) {
+ included = 1;
+ }
+ }
+ }
+
+ if (conf->excludes->nelts) {
+ for (i = 0; included && i < conf->excludes->nelts; i++) {
+ const char *exclude = excludes[i];
+ if (strncmp(r->uri, exclude, strlen(exclude)) == 0) {
+ included = 0;
+ }
+ }
+ }
+
+ return included;
+}
+
+/**
+ * Load the session.
+ *
+ * If the session doesn't exist, a blank one will be created.
+ *
+ * @param r The request
+ * @param z A pointer to where the session will be written.
+ */
+static apr_status_t ap_session_load(request_rec * r, session_rec ** z)
+{
+
+ session_dir_conf *dconf = ap_get_module_config(r->per_dir_config,
+ &session_module);
+ apr_time_t now;
+ session_rec *zz = NULL;
+ int rv = 0;
+
+ /* is the session enabled? */
+ if (!dconf || !dconf->enabled) {
+ return APR_SUCCESS;
+ }
+
+ /* should the session be loaded at all? */
+ if (!session_included(r, dconf)) {
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01814)
+ "excluded by configuration for: %s", r->uri);
+ return APR_SUCCESS;
+ }
+
+ /* load the session from the session hook */
+ rv = ap_run_session_load(r, &zz);
+ if (DECLINED == rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01815)
+ "session is enabled but no session modules have been configured, "
+ "session not loaded: %s", r->uri);
+ return APR_EGENERAL;
+ }
+ else if (OK != rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01816)
+ "error while loading the session, "
+ "session not loaded: %s", r->uri);
+ return rv;
+ }
+
+ /* found a session that hasn't expired? */
+ now = apr_time_now();
+
+ if (zz) {
+ /* load the session attributes */
+ rv = ap_run_session_decode(r, zz);
+
+ /* having a session we cannot decode is just as good as having
+ none at all */
+ if (OK != rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01817)
+ "error while decoding the session, "
+ "session not loaded: %s", r->uri);
+ zz = NULL;
+ }
+
+ /* invalidate session if session is expired */
+ if (zz && zz->expiry && zz->expiry < now) {
+ ap_log_rerror(APLOG_MARK, APLOG_TRACE2, 0, r, "session is expired");
+ zz = NULL;
+ }
+ }
+
+ /* no luck, create a blank session */
+ if (!zz) {
+ zz = (session_rec *) apr_pcalloc(r->pool, sizeof(session_rec));
+ zz->pool = r->pool;
+ zz->entries = apr_table_make(zz->pool, 10);
+ }
+
+ /* make sure the expiry and maxage are set, if present */
+ if (dconf->maxage) {
+ if (!zz->expiry) {
+ zz->expiry = now + dconf->maxage * APR_USEC_PER_SEC;
+ }
+ zz->maxage = dconf->maxage;
+ }
+
+ *z = zz;
+
+ return APR_SUCCESS;
+
+}
+
+/**
+ * Save the session.
+ *
+ * In most implementations the session is only saved if the dirty flag is
+ * true. This prevents the session being saved unnecessarily.
+ *
+ * @param r The request
+ * @param z A pointer to where the session will be written.
+ */
+static apr_status_t ap_session_save(request_rec * r, session_rec * z)
+{
+ if (z) {
+ apr_time_t now = apr_time_now();
+ apr_time_t initialExpiry = z->expiry;
+ int rv = 0;
+
+ session_dir_conf *dconf = ap_get_module_config(r->per_dir_config,
+ &session_module);
+
+ /* sanity checks, should we try save at all? */
+ if (z->written) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01818)
+ "attempt made to save the session twice, "
+ "session not saved: %s", r->uri);
+ return APR_EGENERAL;
+ }
+ if (z->expiry && z->expiry < now) {
+ ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01819)
+ "attempt made to save a session when the session had already expired, "
+ "session not saved: %s", r->uri);
+ return APR_EGENERAL;
+ }
+
+ /* reset the expiry back to maxage, if the expiry is present */
+ if (dconf->maxage) {
+ z->expiry = now + dconf->maxage * APR_USEC_PER_SEC;
+ z->maxage = dconf->maxage;
+ }
+
+ /* reset the expiry before saving if present */
+ if (z->dirty && z->maxage) {
+ z->expiry = now + z->maxage * APR_USEC_PER_SEC;
+ }
+
+ /* don't save if the only change is the expiry by a small amount */
+ if (!z->dirty && dconf->expiry_update_time
+ && (z->expiry - initialExpiry < dconf->expiry_update_time)) {
+ return APR_SUCCESS;
+ }
+
+ /* also don't save sessions that didn't change at all */
+ if (!z->dirty && !z->maxage) {
+ return APR_SUCCESS;
+ }
+
+ /* encode the session */
+ rv = ap_run_session_encode(r, z);
+ if (OK != rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01820)
+ "error while encoding the session, "
+ "session not saved: %s", r->uri);
+ return rv;
+ }
+
+ /* try the save */
+ rv = ap_run_session_save(r, z);
+ if (DECLINED == rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(01821)
+ "session is enabled but no session modules have been configured, "
+ "session not saved: %s", r->uri);
+ return APR_EGENERAL;
+ }
+ else if (OK != rv) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01822)
+ "error while saving the session, "
+ "session not saved: %s", r->uri);
+ return rv;
+ }
+ else {
+ z->written = 1;
+ }
+ }
+
+ return APR_SUCCESS;
+
+}
+
+/**
+ * Get a particular value from the session.
+ * @param r The current request.
+ * @param z The current session. If this value is NULL, the session will be
+ * looked up in the request, created if necessary, and saved to the request
+ * notes.
+ * @param key The key to get.
+ * @param value The buffer to write the value to.
+ */
+static apr_status_t ap_session_get(request_rec * r, session_rec * z,
+ const char *key, const char **value)
+{
+ if (!z) {
+ apr_status_t rv;
+ rv = ap_session_load(r, &z);
+ if (APR_SUCCESS != rv) {
+ return rv;
+ }
+ }
+ if (z && z->entries) {
+ *value = apr_table_get(z->entries, key);
+ }
+
+ return OK;
+}
+
+/**
+ * Set a particular value to the session.
+ *
+ * Using this method ensures that the dirty flag is set correctly, so that
+ * the session can be saved efficiently.
+ * @param r The current request.
+ * @param z The current session. If this value is NULL, the session will be
+ * looked up in the request, created if necessary, and saved to the request
+ * notes.
+ * @param key The key to set. The existing key value will be replaced.
+ * @param value The value to set.
+ */
+static apr_status_t ap_session_set(request_rec * r, session_rec * z,
+ const char *key, const char *value)
+{
+ if (!z) {
+ apr_status_t rv;
+ rv = ap_session_load(r, &z);
+ if (APR_SUCCESS != rv) {
+ return rv;
+ }
+ }
+ if (z) {
+ if (value) {
+ apr_table_set(z->entries, key, value);
+ }
+ else {
+ apr_table_unset(z->entries, key);
+ }
+ z->dirty = 1;
+ }
+ return APR_SUCCESS;
+}
+
+static int identity_count(void *v, const char *key, const char *val)
+{
+ apr_size_t *count = v;
+
+ *count += strlen(key) * 3 + strlen(val) * 3 + 2;
+ return 1;
+}
+
+static int identity_concat(void *v, const char *key, const char *val)
+{
+ char *slider = v;
+ apr_size_t length = strlen(slider);
+
+ slider += length;
+ if (length) {
+ *slider = '&';
+ slider++;
+ }
+ ap_escape_urlencoded_buffer(slider, key);
+ slider += strlen(slider);
+ *slider = '=';
+ slider++;
+ ap_escape_urlencoded_buffer(slider, val);
+ return 1;
+}
+
+/**
+ * Default identity encoding for the session.
+ *
+ * By default, the name value pairs in the session are URLEncoded, separated
+ * by equals, and then in turn separated by ampersand, in the format of an
+ * html form.
+ *
+ * This was chosen to make it easy for external code to unpack a session,
+ * should there be a need to do so.
+ *
+ * @param r The request pointer.
+ * @param z A pointer to where the session will be written.
+ */
+static apr_status_t session_identity_encode(request_rec * r, session_rec * z)
+{
+ char *buffer = NULL;
+ apr_size_t length = 0;
+
+ if (z->expiry) {
+ char *expiry = apr_psprintf(z->pool, "%" APR_INT64_T_FMT, z->expiry);
+ apr_table_setn(z->entries, SESSION_EXPIRY, expiry);
+ }
+ apr_table_do(identity_count, &length, z->entries, NULL);
+ buffer = apr_pcalloc(r->pool, length + 1);
+ apr_table_do(identity_concat, buffer, z->entries, NULL);
+ z->encoded = buffer;
+ return OK;
+
+}
+
+/**
+ * Default identity decoding for the session.
+ *
+ * By default, the name value pairs in the session are URLEncoded, separated
+ * by equals, and then in turn separated by ampersand, in the format of an
+ * html form.
+ *
+ * This was chosen to make it easy for external code to unpack a session,
+ * should there be a need to do so.
+ *
+ * This function reverses that process, and populates the session table.
+ *
+ * Name / value pairs that are not encoded properly are ignored.
+ *
+ * @param r The request pointer.
+ * @param z A pointer to where the session will be written.
+ */
+static apr_status_t session_identity_decode(request_rec * r, session_rec * z)
+{
+
+ char *last = NULL;
+ char *encoded, *pair;
+ const char *sep = "&";
+
+ /* sanity check - anything to decode? */
+ if (!z->encoded) {
+ return OK;
+ }
+
+ /* decode what we have */
+ encoded = apr_pstrdup(r->pool, z->encoded);
+ pair = apr_strtok(encoded, sep, &last);
+ while (pair && pair[0]) {
+ char *plast = NULL;
+ const char *psep = "=";
+ char *key = apr_strtok(pair, psep, &plast);
+ if (key && *key) {
+ char *val = apr_strtok(NULL, sep, &plast);
+ if (!val || !*val) {
+ apr_table_unset(z->entries, key);
+ }
+ else if (!ap_unescape_urlencoded(key) && !ap_unescape_urlencoded(val)) {
+ if (!strcmp(SESSION_EXPIRY, key)) {
+ z->expiry = (apr_time_t) apr_atoi64(val);
+ }
+ else {
+ apr_table_set(z->entries, key, val);
+ }
+ }
+ }
+ pair = apr_strtok(NULL, sep, &last);
+ }
+ z->encoded = NULL;
+ return OK;
+
+}
+
+/**
+ * Ensure any changes to the session are committed.
+ *
+ * This is done in an output filter so that our options for where to
+ * store the session can include storing the session within a cookie:
+ * As an HTTP header, the cookie must be set before the output is
+ * written, but after the handler is run.
+ *
+ * NOTE: It is possible for internal redirects to cause more than one
+ * request to be present, and each request might have a session
+ * defined. We need to go through each session in turn, and save each
+ * one.
+ *
+ * The same session might appear in more than one request. The first
+ * attempt to save the session will be called
+ */
+static apr_status_t session_output_filter(ap_filter_t * f,
+ apr_bucket_brigade * in)
+{
+
+ /* save all the sessions in all the requests */
+ request_rec *r = f->r->main;
+ if (!r) {
+ r = f->r;
+ }
+ while (r) {
+ session_rec *z = NULL;
+ session_dir_conf *conf = ap_get_module_config(r->per_dir_config,
+ &session_module);
+
+ /* load the session, or create one if necessary */
+ /* when unset or on error, z will be NULL */
+ ap_session_load(r, &z);
+ if (!z || z->written) {
+ r = r->next;
+ continue;
+ }
+
+ /* if a header was specified, insert the new values from the header */
+ if (conf->header_set) {
+ const char *override = apr_table_get(r->err_headers_out, conf->header);
+ if (!override) {
+ override = apr_table_get(r->headers_out, conf->header);
+ }
+ if (override) {
+ apr_table_unset(r->err_headers_out, conf->header);
+ apr_table_unset(r->headers_out, conf->header);
+ z->encoded = override;
+ z->dirty = 1;
+ session_identity_decode(r, z);
+ }
+ }
+
+ /* save away the session, and we're done */
+ /* when unset or on error, we've complained to the log */
+ ap_session_save(r, z);
+
+ r = r->next;
+ }
+
+ /* remove ourselves from the filter chain */
+ ap_remove_output_filter(f);
+
+ /* send the data up the stack */
+ return ap_pass_brigade(f->next, in);
+
+}
+
+/**
+ * Insert the output filter.
+ */
+static void session_insert_output_filter(request_rec * r)
+{
+ ap_add_output_filter("MOD_SESSION_OUT", NULL, r, r->connection);
+}
+
+/**
+ * Fixups hook.
+ *
+ * Load the session within a fixup - this ensures that the session is
+ * properly loaded prior to the handler being called.
+ *
+ * The fixup is also responsible for injecting the session into the CGI
+ * environment, should the admin have configured it so.
+ *
+ * @param r The request
+ */
+static int session_fixups(request_rec * r)
+{
+ session_dir_conf *conf = ap_get_module_config(r->per_dir_config,
+ &session_module);
+
+ session_rec *z = NULL;
+
+ /* if an error occurs or no session has been configured, we ignore
+ * the broken session and allow it to be recreated from scratch on save
+ * if necessary.
+ */
+ ap_session_load(r, &z);
+
+ if (conf->env) {
+ if (z) {
+ session_identity_encode(r, z);
+ if (z->encoded) {
+ apr_table_set(r->subprocess_env, HTTP_SESSION, z->encoded);
+ z->encoded = NULL;
+ }
+ }
+ apr_table_unset(r->headers_in, "Session");
+ }
+
+ return OK;
+
+}
+
+
+static void *create_session_dir_config(apr_pool_t * p, char *dummy)
+{
+ session_dir_conf *new =
+ (session_dir_conf *) apr_pcalloc(p, sizeof(session_dir_conf));
+
+ new->includes = apr_array_make(p, 10, sizeof(const char **));
+ new->excludes = apr_array_make(p, 10, sizeof(const char **));
+
+ return (void *) new;
+}
+
+static void *merge_session_dir_config(apr_pool_t * p, void *basev, void *addv)
+{
+ session_dir_conf *new = (session_dir_conf *) apr_pcalloc(p, sizeof(session_dir_conf));
+ session_dir_conf *add = (session_dir_conf *) addv;
+ session_dir_conf *base = (session_dir_conf *) basev;
+
+ new->enabled = (add->enabled_set == 0) ? base->enabled : add->enabled;
+ new->enabled_set = add->enabled_set || base->enabled_set;
+ new->maxage = (add->maxage_set == 0) ? base->maxage : add->maxage;
+ new->maxage_set = add->maxage_set || base->maxage_set;
+ new->header = (add->header_set == 0) ? base->header : add->header;
+ new->header_set = add->header_set || base->header_set;
+ new->env = (add->env_set == 0) ? base->env : add->env;
+ new->env_set = add->env_set || base->env_set;
+ new->includes = apr_array_append(p, base->includes, add->includes);
+ new->excludes = apr_array_append(p, base->excludes, add->excludes);
+ new->expiry_update_time = (add->expiry_update_set == 0)
+ ? base->expiry_update_time
+ : add->expiry_update_time;
+ new->expiry_update_set = add->expiry_update_set || base->expiry_update_set;
+
+ return new;
+}
+
+
+static const char *
+ set_session_enable(cmd_parms * parms, void *dconf, int flag)
+{
+ session_dir_conf *conf = dconf;
+
+ conf->enabled = flag;
+ conf->enabled_set = 1;
+
+ return NULL;
+}
+
+static const char *
+ set_session_maxage(cmd_parms * parms, void *dconf, const char *arg)
+{
+ session_dir_conf *conf = dconf;
+
+ conf->maxage = atol(arg);
+ conf->maxage_set = 1;
+
+ return NULL;
+}
+
+static const char *
+ set_session_header(cmd_parms * parms, void *dconf, const char *arg)
+{
+ session_dir_conf *conf = dconf;
+
+ conf->header = arg;
+ conf->header_set = 1;
+
+ return NULL;
+}
+
+static const char *
+ set_session_env(cmd_parms * parms, void *dconf, int flag)
+{
+ session_dir_conf *conf = dconf;
+
+ conf->env = flag;
+ conf->env_set = 1;
+
+ return NULL;
+}
+
+static const char *add_session_include(cmd_parms * cmd, void *dconf, const char *f)
+{
+ session_dir_conf *conf = dconf;
+
+ const char **new = apr_array_push(conf->includes);
+ *new = f;
+
+ return NULL;
+}
+
+static const char *add_session_exclude(cmd_parms * cmd, void *dconf, const char *f)
+{
+ session_dir_conf *conf = dconf;
+
+ const char **new = apr_array_push(conf->excludes);
+ *new = f;
+
+ return NULL;
+}
+
+static const char *
+ set_session_expiry_update(cmd_parms * parms, void *dconf, const char *arg)
+{
+ session_dir_conf *conf = dconf;
+
+ conf->expiry_update_time = atoi(arg);
+ if (conf->expiry_update_time < 0) {
+ return "SessionExpiryUpdateInterval must be zero (disable) or a positive value";
+ }
+ conf->expiry_update_time = apr_time_from_sec(conf->expiry_update_time);
+ conf->expiry_update_set = 1;
+
+ return NULL;
+}
+
+
+static const command_rec session_cmds[] =
+{
+ AP_INIT_FLAG("Session", set_session_enable, NULL, RSRC_CONF|OR_AUTHCFG,
+ "on if a session should be maintained for these URLs"),
+ AP_INIT_TAKE1("SessionMaxAge", set_session_maxage, NULL, RSRC_CONF|OR_AUTHCFG,
+ "length of time for which a session should be valid. Zero to disable"),
+ AP_INIT_TAKE1("SessionHeader", set_session_header, NULL, RSRC_CONF|OR_AUTHCFG,
+ "output header, if present, whose contents will be injected into the session."),
+ AP_INIT_FLAG("SessionEnv", set_session_env, NULL, RSRC_CONF|OR_AUTHCFG,
+ "on if a session should be written to the CGI environment. Defaults to off"),
+ AP_INIT_TAKE1("SessionInclude", add_session_include, NULL, RSRC_CONF|OR_AUTHCFG,
+ "URL prefixes to include in the session. Defaults to all URLs"),
+ AP_INIT_TAKE1("SessionExclude", add_session_exclude, NULL, RSRC_CONF|OR_AUTHCFG,
+ "URL prefixes to exclude from the session. Defaults to no URLs"),
+ AP_INIT_TAKE1("SessionExpiryUpdateInterval", set_session_expiry_update, NULL, RSRC_CONF|OR_AUTHCFG,
+ "time interval for which a session's expiry time may change "
+ "without having to be rewritten. Zero to disable"),
+ {NULL}
+};
+
+static void register_hooks(apr_pool_t * p)
+{
+ ap_register_output_filter("MOD_SESSION_OUT", session_output_filter,
+ NULL, AP_FTYPE_CONTENT_SET);
+ ap_hook_insert_filter(session_insert_output_filter, NULL, NULL,
+ APR_HOOK_MIDDLE);
+ ap_hook_insert_error_filter(session_insert_output_filter,
+ NULL, NULL, APR_HOOK_MIDDLE);
+ ap_hook_fixups(session_fixups, NULL, NULL, APR_HOOK_MIDDLE);
+ ap_hook_session_encode(session_identity_encode, NULL, NULL,
+ APR_HOOK_REALLY_FIRST);
+ ap_hook_session_decode(session_identity_decode, NULL, NULL,
+ APR_HOOK_REALLY_LAST);
+ APR_REGISTER_OPTIONAL_FN(ap_session_get);
+ APR_REGISTER_OPTIONAL_FN(ap_session_set);
+ APR_REGISTER_OPTIONAL_FN(ap_session_load);
+ APR_REGISTER_OPTIONAL_FN(ap_session_save);
+}
+
+AP_DECLARE_MODULE(session) =
+{
+ STANDARD20_MODULE_STUFF,
+ create_session_dir_config, /* dir config creater */
+ merge_session_dir_config, /* dir merger --- default is to override */
+ NULL, /* server config */
+ NULL, /* merge server config */
+ session_cmds, /* command apr_table_t */
+ register_hooks /* register hooks */
+};