| /* 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. |
| */ |
| |
| /** |
| * This module adds support for https://tools.ietf.org/html/rfc6750 Bearer |
| * tokens, both as a generator of bearer tokens, and as an acceptor of |
| * Bearer tokens for authentication. |
| */ |
| |
| #include "apr_strings.h" |
| #include "apr_hash.h" |
| #include "apr_lib.h" /* for apr_isspace */ |
| #define APR_WANT_STRFUNC /* for strcasecmp */ |
| #include "apr_want.h" |
| |
| #include "ap_config.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 "ap_provider.h" |
| #include "ap_expr.h" |
| |
| #include "mod_auth.h" |
| |
| module AP_MODULE_DECLARE_DATA auth_bearer_module; |
| |
| typedef struct { |
| autht_provider_list *providers; |
| int authoritative; |
| ap_expr_info_t *proxy; |
| unsigned int authoritative_set:1; |
| unsigned int proxy_set:1; |
| } auth_bearer_config_rec; |
| |
| static void *create_auth_bearer_dir_config(apr_pool_t *p, char *d) |
| { |
| auth_bearer_config_rec *conf = apr_pcalloc(p, sizeof(*conf)); |
| |
| /* Any failures are fatal. */ |
| conf->authoritative = 1; |
| |
| return conf; |
| } |
| |
| static void *merge_auth_bearer_dir_config(apr_pool_t *p, void *basev, void *overridesv) |
| { |
| auth_bearer_config_rec *newconf = apr_pcalloc(p, sizeof(*newconf)); |
| auth_bearer_config_rec *base = basev; |
| auth_bearer_config_rec *overrides = overridesv; |
| |
| newconf->authoritative = |
| overrides->authoritative_set ? overrides->authoritative : |
| base->authoritative; |
| newconf->authoritative_set = overrides->authoritative_set |
| || base->authoritative_set; |
| |
| newconf->providers = overrides->providers ? overrides->providers : base->providers; |
| |
| newconf->proxy = |
| overrides->proxy_set ? overrides->proxy : base->proxy; |
| newconf->proxy_set = overrides->proxy_set || base->proxy_set; |
| |
| return newconf; |
| } |
| |
| static const char *add_autht_provider(cmd_parms *cmd, void *config, |
| const char *arg) |
| { |
| auth_bearer_config_rec *conf = (auth_bearer_config_rec*)config; |
| autht_provider_list *newp; |
| |
| newp = apr_pcalloc(cmd->pool, sizeof(autht_provider_list)); |
| newp->provider_name = arg; |
| |
| /* lookup and cache the actual provider now */ |
| newp->provider = ap_lookup_provider(AUTHT_PROVIDER_GROUP, |
| newp->provider_name, |
| AUTHT_PROVIDER_VERSION); |
| |
| if (newp->provider == NULL) { |
| /* by the time they use it, the provider should be loaded and |
| registered with us. */ |
| return apr_psprintf(cmd->pool, |
| "Unknown Autht provider: %s", |
| newp->provider_name); |
| } |
| |
| if (!newp->provider->check_token) { |
| /* if it doesn't provide the appropriate function, reject it */ |
| return apr_psprintf(cmd->pool, |
| "The '%s' Autht provider doesn't support " |
| "Bearer Authentication", newp->provider_name); |
| } |
| |
| /* Add it to the list now. */ |
| if (!conf->providers) { |
| conf->providers = newp; |
| } |
| else { |
| autht_provider_list *last = conf->providers; |
| |
| while (last->next) { |
| last = last->next; |
| } |
| last->next = newp; |
| } |
| |
| return NULL; |
| } |
| |
| static const char *set_authoritative(cmd_parms * cmd, void *config, int flag) |
| { |
| auth_bearer_config_rec *conf = (auth_bearer_config_rec *) config; |
| |
| conf->authoritative = flag; |
| conf->authoritative_set = 1; |
| |
| return NULL; |
| } |
| |
| static const char *set_bearer_proxy(cmd_parms * cmd, void *config, |
| const char *user) |
| { |
| auth_bearer_config_rec *conf = (auth_bearer_config_rec *) config; |
| const char *err; |
| |
| if (!strcasecmp(user, "off")) { |
| conf->proxy = NULL; |
| conf->proxy_set = 1; |
| } |
| else { |
| |
| conf->proxy = |
| ap_expr_parse_cmd(cmd, user, AP_EXPR_FLAG_STRING_RESULT, |
| &err, NULL); |
| if (err) { |
| return apr_psprintf(cmd->pool, |
| "Could not parse proxy expression '%s': %s", user, |
| err); |
| } |
| conf->proxy_set = 1; |
| } |
| |
| return NULL; |
| } |
| |
| static const command_rec auth_bearer_cmds[] = |
| { |
| AP_INIT_ITERATE("AuthBearerProvider", add_autht_provider, NULL, OR_AUTHCFG, |
| "specify the auth providers for a directory or location"), |
| AP_INIT_FLAG("AuthBearerAuthoritative", set_authoritative, NULL, OR_AUTHCFG, |
| "Set to 'Off' to allow access control to be passed along to " |
| "lower modules if the token is not known to this module"), |
| AP_INIT_TAKE1("AuthBearerProxy", set_bearer_proxy, NULL, OR_AUTHCFG, |
| "Pass a bearer authentication token over a proxy connection " |
| "generated using the given expression, 'off' to disable."), |
| {NULL} |
| }; |
| |
| /* These functions return 0 if client is OK, and proper error status |
| * if not... either HTTP_UNAUTHORIZED, if we made a check, and it failed, or |
| * HTTP_INTERNAL_SERVER_ERROR, if things are so totally confused that we |
| * couldn't figure out how to tell if the client is authorized or not. |
| * |
| * If they return DECLINED, and all other modules also decline, that's |
| * treated by the server core as a configuration error, logged and |
| * reported as such. |
| */ |
| |
| static void note_bearer_auth_failure(request_rec *r) |
| { |
| apr_table_setn(r->err_headers_out, |
| (PROXYREQ_PROXY == r->proxyreq) ? "Proxy-Authenticate" |
| : "WWW-Authenticate", |
| apr_pstrcat(r->pool, "Bearer realm=\"", ap_auth_name(r), |
| "\"", NULL)); |
| } |
| |
| static int hook_note_bearer_auth_failure(request_rec *r, const char *auth_type) |
| { |
| if (strcasecmp(auth_type, "Bearer")) |
| return DECLINED; |
| |
| note_bearer_auth_failure(r); |
| return OK; |
| } |
| |
| static int get_bearer_auth(request_rec *r, const char **token) |
| { |
| const char *auth_line; |
| |
| /* Get the appropriate header */ |
| auth_line = apr_table_get(r->headers_in, (PROXYREQ_PROXY == r->proxyreq) |
| ? "Proxy-Authorization" |
| : "Authorization"); |
| |
| if (!auth_line) { |
| note_bearer_auth_failure(r); |
| return HTTP_UNAUTHORIZED; |
| } |
| |
| if (strcasecmp(ap_getword(r->pool, &auth_line, ' '), "Bearer")) { |
| /* Client tried to authenticate using wrong auth scheme */ |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10448) |
| "client used wrong authentication scheme: %s", r->uri); |
| note_bearer_auth_failure(r); |
| return HTTP_UNAUTHORIZED; |
| } |
| |
| /* Skip leading spaces. */ |
| while (apr_isspace(*auth_line)) { |
| auth_line++; |
| } |
| |
| *token = auth_line; |
| |
| return OK; |
| } |
| |
| /* Determine the token, and check if we can process the token, for HTTP |
| * bearer authentication... |
| */ |
| static int authenticate_bearer_token(request_rec *r) |
| { |
| auth_bearer_config_rec *conf = ap_get_module_config(r->per_dir_config, |
| &auth_bearer_module); |
| const char *sent_token, *current_auth; |
| int res; |
| autht_status auth_result; |
| autht_provider_list *current_provider; |
| |
| /* Are we configured to be Bearer auth? */ |
| current_auth = ap_auth_type(r); |
| if (!current_auth || strcasecmp(current_auth, "Bearer")) { |
| return DECLINED; |
| } |
| |
| /* We need an authentication realm. */ |
| if (!ap_auth_name(r)) { |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10449) |
| "need AuthName: %s", r->uri); |
| return HTTP_INTERNAL_SERVER_ERROR; |
| } |
| |
| r->ap_auth_type = (char*)current_auth; |
| |
| res = get_bearer_auth(r, &sent_token); |
| if (res) { |
| return res; |
| } |
| |
| current_provider = conf->providers; |
| do { |
| const autht_provider *provider; |
| |
| /* For now, if a provider isn't set, we'll be nice and use the jwt |
| * provider. |
| */ |
| if (!current_provider) { |
| provider = ap_lookup_provider(AUTHT_PROVIDER_GROUP, |
| AUTHT_DEFAULT_PROVIDER, |
| AUTHT_PROVIDER_VERSION); |
| |
| if (!provider || !provider->check_token) { |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10424) |
| "No Autht provider configured"); |
| auth_result = AUTHT_GENERAL_ERROR; |
| break; |
| } |
| apr_table_setn(r->notes, AUTHT_PROVIDER_NAME_NOTE, AUTHT_DEFAULT_PROVIDER); |
| } |
| else { |
| provider = current_provider->provider; |
| apr_table_setn(r->notes, AUTHT_PROVIDER_NAME_NOTE, current_provider->provider_name); |
| } |
| |
| auth_result = provider->check_token(r, "bearer", sent_token); |
| |
| apr_table_unset(r->notes, AUTHT_PROVIDER_NAME_NOTE); |
| |
| /* Something occurred. Stop checking. */ |
| if (auth_result != AUTHT_MISMATCH) { |
| break; |
| } |
| |
| /* If we're not really configured for providers, stop now. */ |
| if (!conf->providers) { |
| break; |
| } |
| |
| current_provider = current_provider->next; |
| } while (current_provider); |
| |
| if (auth_result != AUTHT_GRANTED) { |
| int return_code; |
| |
| /* If we're not authoritative, then any error is ignored. */ |
| if (!(conf->authoritative) && auth_result != AUTHT_DENIED) { |
| return DECLINED; |
| } |
| |
| switch (auth_result) { |
| case AUTHT_DENIED: |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10425) |
| "bearer token %s: authentication failure for \"%s\": " |
| "Token Rejected", |
| sent_token, r->uri); |
| return_code = HTTP_UNAUTHORIZED; |
| break; |
| case AUTHT_EXPIRED: |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10426) |
| "bearer token %s: authentication failure for \"%s\": " |
| "Token has expired", |
| sent_token, r->uri); |
| return_code = HTTP_UNAUTHORIZED; |
| break; |
| case AUTHT_INVALID: |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10427) |
| "bearer token %s: authentication failure for \"%s\": " |
| "Token is not yet valid", |
| sent_token, r->uri); |
| return_code = HTTP_UNAUTHORIZED; |
| break; |
| case AUTHT_MISMATCH: |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10428) |
| "bearer token %s: did not match '%s': %s", sent_token, |
| ap_auth_name(r), r->uri); |
| return_code = HTTP_UNAUTHORIZED; |
| break; |
| case AUTH_GENERAL_ERROR: |
| default: |
| /* We'll assume that the module has already said what its error |
| * was in the logs. |
| */ |
| return_code = HTTP_INTERNAL_SERVER_ERROR; |
| break; |
| } |
| |
| /* If we're returning 401, tell them to try again. */ |
| if (return_code == HTTP_UNAUTHORIZED) { |
| note_bearer_auth_failure(r); |
| } |
| return return_code; |
| } |
| |
| return OK; |
| } |
| |
| /* If we have set claims to be made, create a bearer authentication header |
| * for the benefit of a proxy or application running behind this server. |
| */ |
| static int authenticate_bearer_fixup(request_rec *r) |
| { |
| const char *auth_line, *token, *err; |
| auth_bearer_config_rec *conf = ap_get_module_config(r->per_dir_config, |
| &auth_bearer_module); |
| |
| if (!conf->proxy) { |
| return DECLINED; |
| } |
| |
| token = ap_expr_str_exec(r, conf->proxy, &err); |
| if (err) { |
| ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10429) |
| "AuthBearerProxy: could not evaluate token expression for URI '%s': %s", r->uri, err); |
| return HTTP_INTERNAL_SERVER_ERROR; |
| } |
| if (!token || !*token) { |
| ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(10430) |
| "AuthBearerProxy: empty token expression for URI '%s', ignoring", r->uri); |
| |
| apr_table_unset(r->headers_in, "Authorization"); |
| |
| return DECLINED; |
| } |
| |
| auth_line = apr_pstrcat(r->pool, "Bearer ", token, |
| NULL); |
| apr_table_setn(r->headers_in, "Authorization", auth_line); |
| |
| ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(10431) |
| "AuthBearerProxy: \"Authorization: %s\"", |
| auth_line); |
| |
| return OK; |
| } |
| |
| static void register_hooks(apr_pool_t *p) |
| { |
| ap_hook_check_autht(authenticate_bearer_token, NULL, NULL, APR_HOOK_MIDDLE, |
| AP_AUTH_INTERNAL_PER_CONF); |
| ap_hook_fixups(authenticate_bearer_fixup, NULL, NULL, APR_HOOK_LAST); |
| ap_hook_note_auth_failure(hook_note_bearer_auth_failure, NULL, NULL, |
| APR_HOOK_MIDDLE); |
| } |
| |
| AP_DECLARE_MODULE(auth_bearer) = |
| { |
| STANDARD20_MODULE_STUFF, |
| create_auth_bearer_dir_config, /* dir config creater */ |
| merge_auth_bearer_dir_config, /* dir merger --- default is to override */ |
| NULL, /* server config */ |
| NULL, /* merge server config */ |
| auth_bearer_cmds, /* command apr_table_t */ |
| register_hooks /* register hooks */ |
| }; |
