Adding upstream version 2.4.56.upstream/2.4.56

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 475 insertions, 0 deletions

diff --git a/modules/aaa/mod_authn_socache.c b/modules/aaa/mod_authn_socache.c
new file mode 100644
index 0000000..0e4454a
--- /dev/null
+++ b/modules/aaa/mod_authn_socache.c
@@ -0,0 +1,475 @@
+/* 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 "apr_strings.h"
+#include "apr_md5.h"            /* for apr_password_validate */
+
+#include "ap_config.h"
+#include "ap_provider.h"
+#include "httpd.h"
+#include "http_config.h"
+#include "http_core.h"
+#include "http_log.h"
+#include "http_protocol.h"
+#include "http_request.h"
+
+#include "mod_auth.h"
+
+#include "ap_socache.h"
+#include "util_mutex.h"
+#include "apr_optional.h"
+
+module AP_MODULE_DECLARE_DATA authn_socache_module;
+
+typedef struct authn_cache_dircfg {
+    apr_interval_time_t timeout;
+    apr_array_header_t *providers;
+    const char *context;
+} authn_cache_dircfg;
+
+/* FIXME:
+ * I think the cache and mutex should be global
+ */
+static apr_global_mutex_t *authn_cache_mutex = NULL;
+static ap_socache_provider_t *socache_provider = NULL;
+static ap_socache_instance_t *socache_instance = NULL;
+static const char *const authn_cache_id = "authn-socache";
+static int configured;
+
+static apr_status_t remove_lock(void *data)
+{
+    if (authn_cache_mutex) {
+        apr_global_mutex_destroy(authn_cache_mutex);
+        authn_cache_mutex = NULL;
+    }
+    return APR_SUCCESS;
+}
+
+static apr_status_t destroy_cache(void *data)
+{
+    if (socache_instance) {
+        socache_provider->destroy(socache_instance, (server_rec*)data);
+        socache_instance = NULL;
+    }
+    return APR_SUCCESS;
+}
+
+static int authn_cache_precfg(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptmp)
+{
+    apr_status_t rv = ap_mutex_register(pconf, authn_cache_id,
+                                        NULL, APR_LOCK_DEFAULT, 0);
+    if (rv != APR_SUCCESS) {
+        ap_log_perror(APLOG_MARK, APLOG_CRIT, rv, plog, APLOGNO(01673)
+                      "failed to register %s mutex", authn_cache_id);
+        return 500; /* An HTTP status would be a misnomer! */
+    }
+    socache_provider = ap_lookup_provider(AP_SOCACHE_PROVIDER_GROUP,
+                                          AP_SOCACHE_DEFAULT_PROVIDER,
+                                          AP_SOCACHE_PROVIDER_VERSION);
+    configured = 0;
+    return OK;
+}
+
+static int authn_cache_post_config(apr_pool_t *pconf, apr_pool_t *plog,
+                                   apr_pool_t *ptmp, server_rec *s)
+{
+    apr_status_t rv;
+    static struct ap_socache_hints authn_cache_hints = {64, 32, 60000000};
+    const char *errmsg;
+
+    if (!configured) {
+        return OK;    /* don't waste the overhead of creating mutex & cache */
+    }
+    if (socache_provider == NULL) {
+        ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, plog, APLOGNO(01674)
+                      "Please select a socache provider with AuthnCacheSOCache "
+                      "(no default found on this platform). Maybe you need to "
+                      "load mod_socache_shmcb or another socache module first");
+        return 500; /* An HTTP status would be a misnomer! */
+    }
+
+    /* We have socache_provider, but do not have socache_instance. This should
+     * happen only when using "default" socache_provider, so create default
+     * socache_instance in this case. */
+    if (socache_instance == NULL) {
+        errmsg = socache_provider->create(&socache_instance, NULL,
+                                          ptmp, pconf);
+        if (errmsg) {
+            ap_log_perror(APLOG_MARK, APLOG_CRIT, 0, plog, APLOGNO(02612)
+                        "failed to create mod_socache_shmcb socache "
+                        "instance: %s", errmsg);
+            return 500;
+        }
+    }
+
+    rv = ap_global_mutex_create(&authn_cache_mutex, NULL,
+                                authn_cache_id, NULL, s, pconf, 0);
+    if (rv != APR_SUCCESS) {
+        ap_log_perror(APLOG_MARK, APLOG_CRIT, rv, plog, APLOGNO(01675)
+                      "failed to create %s mutex", authn_cache_id);
+        return 500; /* An HTTP status would be a misnomer! */
+    }
+    apr_pool_cleanup_register(pconf, NULL, remove_lock, apr_pool_cleanup_null);
+
+    rv = socache_provider->init(socache_instance, authn_cache_id,
+                                &authn_cache_hints, s, pconf);
+    if (rv != APR_SUCCESS) {
+        ap_log_perror(APLOG_MARK, APLOG_CRIT, rv, plog, APLOGNO(01677)
+                      "failed to initialise %s cache", authn_cache_id);
+        return 500; /* An HTTP status would be a misnomer! */
+    }
+    apr_pool_cleanup_register(pconf, (void*)s, destroy_cache, apr_pool_cleanup_null);
+    return OK;
+}
+
+static void authn_cache_child_init(apr_pool_t *p, server_rec *s)
+{
+    const char *lock;
+    apr_status_t rv;
+    if (!configured) {
+        return;       /* don't waste the overhead of creating mutex & cache */
+    }
+    lock = apr_global_mutex_lockfile(authn_cache_mutex);
+    rv = apr_global_mutex_child_init(&authn_cache_mutex, lock, p);
+    if (rv != APR_SUCCESS) {
+        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s, APLOGNO(01678)
+                     "failed to initialise mutex in child_init");
+    }
+}
+
+static const char *authn_cache_socache(cmd_parms *cmd, void *CFG,
+                                       const char *arg)
+{
+    const char *errmsg = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+    const char *sep, *name;
+
+    if (errmsg)
+        return errmsg;
+
+    /* Argument is of form 'name:args' or just 'name'. */
+    sep = ap_strchr_c(arg, ':');
+    if (sep) {
+        name = apr_pstrmemdup(cmd->pool, arg, sep - arg);
+        sep++;
+    }
+    else {
+        name = arg;
+    }
+
+    socache_provider = ap_lookup_provider(AP_SOCACHE_PROVIDER_GROUP, name,
+                                          AP_SOCACHE_PROVIDER_VERSION);
+    if (socache_provider == NULL) {
+        errmsg = apr_psprintf(cmd->pool,
+                              "Unknown socache provider '%s'. Maybe you need "
+                              "to load the appropriate socache module "
+                              "(mod_socache_%s?)", arg, arg);
+    }
+    else {
+        errmsg = socache_provider->create(&socache_instance, sep,
+                                          cmd->temp_pool, cmd->pool);
+    }
+
+    if (errmsg) {
+        errmsg = apr_psprintf(cmd->pool, "AuthnCacheSOCache: %s", errmsg);
+    }
+    return errmsg;
+}
+
+static const char *authn_cache_enable(cmd_parms *cmd, void *CFG)
+{
+    const char *errmsg = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+    configured = 1;
+    return errmsg;
+}
+
+static const char *const directory = "directory";
+static void* authn_cache_dircfg_create(apr_pool_t *pool, char *s)
+{
+    authn_cache_dircfg *ret = apr_palloc(pool, sizeof(authn_cache_dircfg));
+    ret->timeout = apr_time_from_sec(300);
+    ret->providers = NULL;
+    ret->context = directory;
+    return ret;
+}
+
+/* not sure we want this.  Might be safer to document use-all-or-none */
+static void* authn_cache_dircfg_merge(apr_pool_t *pool, void *BASE, void *ADD)
+{
+    authn_cache_dircfg *base = BASE;
+    authn_cache_dircfg *add = ADD;
+    authn_cache_dircfg *ret = apr_pmemdup(pool, add, sizeof(authn_cache_dircfg));
+    /* preserve context and timeout if not defaults */
+    if (add->context == directory) {
+        ret->context = base->context;
+    }
+    if (add->timeout == apr_time_from_sec(300)) {
+        ret->timeout = base->timeout;
+    }
+    if (add->providers == NULL) {
+        ret->providers = base->providers;
+    }
+    return ret;
+}
+
+static const char *authn_cache_setprovider(cmd_parms *cmd, void *CFG,
+                                           const char *arg)
+{
+    authn_cache_dircfg *cfg = CFG;
+    if (cfg->providers == NULL) {
+        cfg->providers = apr_array_make(cmd->pool, 4, sizeof(const char*));
+    }
+    APR_ARRAY_PUSH(cfg->providers, const char*) = arg;
+    configured = 1;
+    return NULL;
+}
+
+static const char *authn_cache_timeout(cmd_parms *cmd, void *CFG,
+                                       const char *arg)
+{
+    authn_cache_dircfg *cfg = CFG;
+    int secs = atoi(arg);
+    cfg->timeout = apr_time_from_sec(secs);
+    return NULL;
+}
+
+static const command_rec authn_cache_cmds[] =
+{
+    /* global stuff: cache and mutex */
+    AP_INIT_TAKE1("AuthnCacheSOCache", authn_cache_socache, NULL, RSRC_CONF,
+                  "socache provider for authn cache"),
+    AP_INIT_NO_ARGS("AuthnCacheEnable", authn_cache_enable, NULL, RSRC_CONF,
+                    "enable socache configuration in htaccess even if not enabled anywhere else"),
+    /* per-dir stuff */
+    AP_INIT_ITERATE("AuthnCacheProvideFor", authn_cache_setprovider, NULL,
+                    OR_AUTHCFG, "Determine what authn providers to cache for"),
+    AP_INIT_TAKE1("AuthnCacheTimeout", authn_cache_timeout, NULL,
+                  OR_AUTHCFG, "Timeout (secs) for cached credentials"),
+    AP_INIT_TAKE1("AuthnCacheContext", ap_set_string_slot,
+                  (void*)APR_OFFSETOF(authn_cache_dircfg, context),
+                  ACCESS_CONF, "Context for authn cache"),
+    {NULL}
+};
+
+static const char *construct_key(request_rec *r, const char *context,
+                                 const char *user, const char *realm)
+{
+    /* handle "special" context values */
+    if (!strcmp(context, directory)) {
+        /* FIXME: are we at risk of this blowing up? */
+        char *new_context;
+        char *slash = strrchr(r->uri, '/');
+        new_context = apr_palloc(r->pool, slash - r->uri +
+                                 strlen(r->server->server_hostname) + 1);
+        strcpy(new_context, r->server->server_hostname);
+        strncat(new_context, r->uri, slash - r->uri);
+        context = new_context;
+    }
+    else if (!strcmp(context, "server")) {
+        context = r->server->server_hostname;
+    }
+    /* any other context value is literal */
+
+    if (realm == NULL) {                              /* basic auth */
+        return apr_pstrcat(r->pool, context, ":", user, NULL);
+    }
+    else {                                            /* digest auth */
+        return apr_pstrcat(r->pool, context, ":", user, ":", realm, NULL);
+    }
+}
+
+static void ap_authn_cache_store(request_rec *r, const char *module,
+                                 const char *user, const char *realm,
+                                 const char* data)
+{
+    apr_status_t rv;
+    authn_cache_dircfg *dcfg;
+    const char *key;
+    apr_time_t expiry;
+
+    /* first check whether we're caching for this module */
+    dcfg = ap_get_module_config(r->per_dir_config, &authn_socache_module);
+    if (!configured || !dcfg->providers) {
+        return;
+    }
+    if (!ap_array_str_contains(dcfg->providers, module)) {
+        return;
+    }
+
+    /* OK, we're on.  Grab mutex to do our business */
+    rv = apr_global_mutex_trylock(authn_cache_mutex);
+    if (APR_STATUS_IS_EBUSY(rv)) {
+        /* don't wait around; just abandon it */
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r, APLOGNO(01679)
+                      "authn credentials for %s not cached (mutex busy)", user);
+        return;
+    }
+    else if (rv != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01680)
+                      "Failed to cache authn credentials for %s in %s",
+                      module, dcfg->context);
+        return;
+    }
+
+    /* We have the mutex, so go ahead */
+    /* first build our key and determine expiry time */
+    key = construct_key(r, dcfg->context, user, realm);
+    expiry = apr_time_now() + dcfg->timeout;
+
+    /* store it */
+    rv = socache_provider->store(socache_instance, r->server,
+                                 (unsigned char*)key, strlen(key), expiry,
+                                 (unsigned char*)data, strlen(data), r->pool);
+    if (rv == APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01681)
+                      "Cached authn credentials for %s in %s",
+                      user, dcfg->context);
+    }
+    else {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01682)
+                      "Failed to cache authn credentials for %s in %s",
+                      module, dcfg->context);
+    }
+
+    /* We're done with the mutex */
+    rv = apr_global_mutex_unlock(authn_cache_mutex);
+    if (rv != APR_SUCCESS) {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01683) "Failed to release mutex!");
+    }
+}
+
+#define MAX_VAL_LEN 256
+static authn_status check_password(request_rec *r, const char *user,
+                                   const char *password)
+{
+    /* construct key
+     * look it up
+     * if found, test password
+     *
+     * mutexing here would be a big performance drag.
+     * It's definitely unnecessary with some backends (like ndbm or gdbm)
+     * Is there a risk in the general case?  I guess the only risk we
+     * care about is a race condition that gets us a dangling pointer
+     * to no-longer-defined memory.  Hmmm ...
+     */
+    apr_status_t rv;
+    const char *key;
+    authn_cache_dircfg *dcfg;
+    unsigned char val[MAX_VAL_LEN];
+    unsigned int vallen = MAX_VAL_LEN - 1;
+    dcfg = ap_get_module_config(r->per_dir_config, &authn_socache_module);
+    if (!configured || !dcfg->providers) {
+        return AUTH_USER_NOT_FOUND;
+    }
+    key = construct_key(r, dcfg->context, user, NULL);
+    rv = socache_provider->retrieve(socache_instance, r->server,
+                                    (unsigned char*)key, strlen(key),
+                                    val, &vallen, r->pool);
+
+    if (APR_STATUS_IS_NOTFOUND(rv)) {
+        /* not found - just return */
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01684)
+                      "Authn cache: no credentials found for %s", user);
+        return AUTH_USER_NOT_FOUND;
+    }
+    else if (rv == APR_SUCCESS) {
+        /* OK, we got a value */
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01685)
+                      "Authn cache: found credentials for %s", user);
+        val[vallen] = 0;
+    }
+    else {
+        /* error: give up and pass the buck */
+        /* FIXME: getting this for NOTFOUND - prolly a bug in mod_socache */
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01686)
+                      "Error accessing authentication cache");
+        return AUTH_USER_NOT_FOUND;
+    }
+
+    rv = apr_password_validate(password, (char*) val);
+    if (rv != APR_SUCCESS) {
+        return AUTH_DENIED;
+    }
+
+    return AUTH_GRANTED;
+}
+
+static authn_status get_realm_hash(request_rec *r, const char *user,
+                                   const char *realm, char **rethash)
+{
+    apr_status_t rv;
+    const char *key;
+    authn_cache_dircfg *dcfg;
+    unsigned char val[MAX_VAL_LEN];
+    unsigned int vallen = MAX_VAL_LEN - 1;
+    dcfg = ap_get_module_config(r->per_dir_config, &authn_socache_module);
+    if (!configured || !dcfg->providers) {
+        return AUTH_USER_NOT_FOUND;
+    }
+    key = construct_key(r, dcfg->context, user, realm);
+    rv = socache_provider->retrieve(socache_instance, r->server,
+                                    (unsigned char*)key, strlen(key),
+                                    val, &vallen, r->pool);
+
+    if (APR_STATUS_IS_NOTFOUND(rv)) {
+        /* not found - just return */
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01687)
+                      "Authn cache: no credentials found for %s", user);
+        return AUTH_USER_NOT_FOUND;
+    }
+    else if (rv == APR_SUCCESS) {
+        /* OK, we got a value */
+        ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01688)
+                      "Authn cache: found credentials for %s", user);
+    }
+    else {
+        /* error: give up and pass the buck */
+        /* FIXME: getting this for NOTFOUND - prolly a bug in mod_socache */
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(01689)
+                      "Error accessing authentication cache");
+        return AUTH_USER_NOT_FOUND;
+    }
+    *rethash = apr_pstrmemdup(r->pool, (char *)val, vallen);
+
+    return AUTH_USER_FOUND;
+}
+
+static const authn_provider authn_cache_provider =
+{
+    &check_password,
+    &get_realm_hash,
+};
+
+static void register_hooks(apr_pool_t *p)
+{
+    ap_register_auth_provider(p, AUTHN_PROVIDER_GROUP, "socache",
+                              AUTHN_PROVIDER_VERSION,
+                              &authn_cache_provider, AP_AUTH_INTERNAL_PER_CONF);
+    APR_REGISTER_OPTIONAL_FN(ap_authn_cache_store);
+    ap_hook_pre_config(authn_cache_precfg, NULL, NULL, APR_HOOK_MIDDLE);
+    ap_hook_post_config(authn_cache_post_config, NULL, NULL, APR_HOOK_MIDDLE);
+    ap_hook_child_init(authn_cache_child_init, NULL, NULL, APR_HOOK_MIDDLE);
+}
+
+AP_DECLARE_MODULE(authn_socache) =
+{
+    STANDARD20_MODULE_STUFF,
+    authn_cache_dircfg_create,
+    authn_cache_dircfg_merge,
+    NULL,
+    NULL,
+    authn_cache_cmds,
+    register_hooks
+};