generate or propagate traceparent header

- using OIDCTraceParent; closes #1152; thanks @studersi
- include hostname/port/pid in User-Agent header on outgoing requests
- bump to 2.4.15rc12

Signed-off-by: Hans Zandbelt <hans.zandbelt@openidc.com>

ChangeLog

@@ -1,3 +1,8 @@
+12/20/2023
+- generate or propagate traceparent header using OIDCTraceParent; closes #1152; thanks @studersi
+- include hostname,port and process id in User-Agent header on outgoing requests
+- bump to 2.4.15rc12
+
 12/19/2023
 - metrics update:
   - rename "requests" class to "provider"

auth_openidc.conf

@@ -1017,7 +1017,7 @@
 #   authn           Authentication request creation and response processing.
 #   authz           Authorization errors per OIDCUnAuthzAction (per Require statement, not overall).
 #   require.claim   Match/failure count of Require claim directives (per Require statement, not overall).
-#   provider        Requests to the provider endpoints. 
+#   provider        Requests to the provider [token, userinfo, metadata] endpoints.
 #   session         Existing session processing.
 #   cache           Cache read/write timings and errors.
 #   redirect_uri    Requests to the Redirect URI, per type.
@@ -1036,6 +1036,12 @@
 # When not defined, no metrics will be published on the enclosing vhost.
 #OIDCMetricsPublish <path>
 
+# Set a traceparent HTTP header on outgoing requests to the provider and proxied requests.
+#   propagate: propagate any existing traceparent header on requests to the Provider (it's proxied as it is)
+#   generate:  generate a traceparent header, possibly overwriting an existing one
+# The default is to not add (or overwrite) a traceparent header.
+#OIDCTraceParent generate | propagate
+
 # Specify claims that should be removed from the userinfo and/or id_token before storing them in the session.
 # Note that OIDCBlackListedClaims takes precedence over OIDCWhiteListedClaims
 # When not defined no claims are blacklisted and all claims are stored except when OIDCWhiteListedClaims is used.

configure.ac

@@ -1,4 +1,4 @@
-AC_INIT([mod_auth_openidc],[2.4.15rc11],[hans.zandbelt@openidc.com])
+AC_INIT([mod_auth_openidc],[2.4.15rc12],[hans.zandbelt@openidc.com])
 
 AC_SUBST(NAMEVER, AC_PACKAGE_TARNAME()-AC_PACKAGE_VERSION())
 

src/config.c

@@ -293,6 +293,7 @@
 #define OIDCXForwardedHeaders "OIDCXForwardedHeaders"
 #define OIDCUserInfoClaimsExpr "OIDCUserInfoClaimsExpr"
 #define OIDCFilterClaimsExpr "OIDCFilterClaimsExpr"
+#define OIDCTraceParent "OIDCTraceParent"
 
 extern module AP_MODULE_DECLARE_DATA auth_openidc_module;
 
@@ -1137,6 +1138,12 @@ static const char *oidc_set_metrics_hook_data(cmd_parms *cmd, void *m, const cha
 	return NULL;
 }
 
+static const char *oidc_set_trace_parent(cmd_parms *cmd, void *struct_ptr, const char *arg) {
+	oidc_cfg *cfg = (oidc_cfg *)ap_get_module_config(cmd->server->module_config, &auth_openidc_module);
+	const char *rv = oidc_parse_trace_parent(cmd->pool, arg, &cfg->trace_parent);
+	return OIDC_CONFIG_DIR_RV(cmd, rv);
+}
+
 static const char *oidc_set_filtered_claims(cmd_parms *cmd, void *m, const char *arg) {
 	oidc_cfg *cfg = (oidc_cfg *)ap_get_module_config(cmd->server->module_config, &auth_openidc_module);
 	int offset = (int)(long)cmd->info;
@@ -1657,6 +1664,7 @@ void *oidc_create_server_config(apr_pool_t *pool, server_rec *svr) {
 	c->info_hook_data = NULL;
 	c->metrics_hook_data = NULL;
 	c->metrics_path = NULL;
+	c->trace_parent = OIDC_TRACE_PARENT_OFF;
 
 	c->black_listed_claims = NULL;
 	c->white_listed_claims = NULL;
@@ -1906,6 +1914,7 @@ void *oidc_merge_server_config(apr_pool_t *pool, void *BASE, void *ADD) {
 	c->info_hook_data = add->info_hook_data != NULL ? add->info_hook_data : base->info_hook_data;
 	c->metrics_hook_data = add->metrics_hook_data != NULL ? add->metrics_hook_data : base->metrics_hook_data;
 	c->metrics_path = add->metrics_path != NULL ? add->metrics_path : base->metrics_path;
+	c->trace_parent = add->trace_parent != OIDC_TRACE_PARENT_OFF ? add->trace_parent : base->trace_parent;
 
 	c->black_listed_claims =
 	    add->black_listed_claims != NULL ? add->black_listed_claims : base->black_listed_claims;
@@ -3409,6 +3418,11 @@ const command_rec oidc_config_cmds[] = {
 				(void *)APR_OFFSETOF(oidc_cfg, metrics_path),
 				RSRC_CONF,
 				"Define the URL where the metrics will be published (e.g.: /metrics)"),
+		AP_INIT_TAKE1(OIDCTraceParent,
+				oidc_set_trace_parent,
+				(void *)APR_OFFSETOF(oidc_cfg, trace_parent),
+				RSRC_CONF,
+				"Define to propagagte or generate a traceparent header"),
 		AP_INIT_ITERATE(OIDCBlackListedClaims,
 				oidc_set_filtered_claims,
 				(void *) APR_OFFSETOF(oidc_cfg, black_listed_claims),

src/mod_auth_openidc.c

@@ -1919,7 +1919,7 @@ static apr_byte_t oidc_save_in_session(request_rec *r, oidc_cfg *c, oidc_session
 				       const char *original_url, const char *userinfo_jwt) {
 
 	/* store the user in the session */
-	session->remote_user = remoteUser;
+	session->remote_user = apr_pstrdup(r->pool, remoteUser);
 
 	/* set the session expiry to the inactivity timeout */
 	session->expiry = apr_time_now() + apr_time_from_sec(c->session_inactivity_timeout);
@@ -4281,6 +4281,8 @@ int oidc_check_user_id(request_rec *r) {
 		return DECLINED;
 	}
 
+	oidc_util_set_trace_parent(r, c, NULL);
+
 	OIDC_METRICS_COUNTER_INC(r, c, OM_AUTHTYPE_MOD_AUTH_OPENIDC);
 
 	/* see if we've configured OpenID Connect user authentication for this request */

src/mod_auth_openidc.h

@@ -129,6 +129,7 @@ APLOG_USE_MODULE(auth_openidc);
 #define OIDC_REQUEST_STATE_KEY_DISCOVERY "d"
 #define OIDC_REQUEST_STATE_KEY_AUTHN "a"
 #define OIDC_REQUEST_STATE_KEY_SAVE "s"
+#define OIDC_REQUEST_STATE_TRACE_ID "t"
 
 /* parameter name of the callback URL in the discovery response */
 #define OIDC_DISC_CB_PARAM "oidc_callback"
@@ -285,6 +286,10 @@ APLOG_USE_MODULE(auth_openidc);
 #define OIDC_HDR_X_FORWARDED_PROTO 4
 #define OIDC_HDR_FORWARDED 8
 
+#define OIDC_TRACE_PARENT_OFF 0
+#define OIDC_TRACE_PARENT_PROPAGATE 1
+#define OIDC_TRACE_PARENT_GENERATE 2
+
 typedef apr_byte_t (*oidc_proto_pkce_state)(request_rec *r, char **state);
 typedef apr_byte_t (*oidc_proto_pkce_challenge)(request_rec *r, const char *state, char **code_challenge);
 typedef apr_byte_t (*oidc_proto_pkce_verifier)(request_rec *r, const char *state, char **code_verifier);
@@ -512,6 +517,7 @@ typedef struct oidc_cfg {
 	apr_hash_t *info_hook_data;
 	apr_hash_t *metrics_hook_data;
 	char *metrics_path;
+	int trace_parent;
 
 	apr_hash_t *black_listed_claims;
 	apr_hash_t *white_listed_claims;
@@ -985,6 +991,7 @@ oidc_jwk_t *oidc_util_key_list_first(const apr_array_header_t *key_list, int kty
 const char *oidc_util_jq_filter(request_rec *r, const char *input, const char *filter);
 char *oidc_util_apr_expr_parse(cmd_parms *cmd, const char *str, oidc_apr_expr_t **expr, apr_byte_t result_is_str);
 const char *oidc_util_apr_expr_exec(request_rec *r, const oidc_apr_expr_t *expr, apr_byte_t result_is_str);
+void oidc_util_set_trace_parent(request_rec *r, oidc_cfg *c, const char *span);
 
 /* HTTP header constants */
 #define OIDC_HTTP_HDR_COOKIE "Cookie"
@@ -1010,6 +1017,7 @@ const char *oidc_util_apr_expr_exec(request_rec *r, const oidc_apr_expr_t *expr,
 #define OIDC_HTTP_HDR_EXPIRES "Expires"
 #define OIDC_HTTP_HDR_X_FRAME_OPTIONS "X-Frame-Options"
 #define OIDC_HTTP_HDR_WWW_AUTHENTICATE "WWW-Authenticate"
+#define OIDC_HTTP_HDR_TRACE_PARENT "traceparent"
 
 #define OIDC_HTTP_HDR_VAL_XML_HTTP_REQUEST "XMLHttpRequest"
 #define OIDC_HTTP_HDR_VAL_NAVIGATE "navigate"
@@ -1032,6 +1040,7 @@ const char *oidc_util_hdr_in_x_forwarded_port_get(const request_rec *r);
 const char *oidc_util_hdr_in_x_forwarded_host_get(const request_rec *r);
 const char *oidc_util_hdr_in_forwarded_get(const request_rec *r);
 const char *oidc_util_hdr_in_host_get(const request_rec *r);
+const char *oidc_util_hdr_in_traceparent_get(const request_rec *r);
 void oidc_util_hdr_out_location_set(const request_rec *r, const char *value);
 const char *oidc_util_hdr_out_location_get(const request_rec *r);
 void oidc_util_hdr_err_out_add(const request_rec *r, const char *name, const char *value);
@@ -1056,15 +1065,15 @@ apr_byte_t oidc_oauth_metadata_provider_parse(request_rec *r, oidc_cfg *c, json_
 
 // oidc_session.c
 typedef struct {
-	char *uuid;		 /* unique id */
-	const char *remote_user; /* user who owns this particular session */
-	json_t *state;		 /* the state for this session, encoded in a JSON object */
-	apr_time_t expiry;	 /* if > 0, the time of expiry of this session */
-	const char *sid;
+	char *uuid;	   /* unique id */
+	char *remote_user; /* user who owns this particular session */
+	json_t *state;	   /* the state for this session, encoded in a JSON object */
+	apr_time_t expiry; /* if > 0, the time of expiry of this session */
+	char *sid;
 } oidc_session_t;
 
 apr_byte_t oidc_session_load(request_rec *r, oidc_session_t **z);
-apr_byte_t oidc_session_get(request_rec *r, oidc_session_t *z, const char *key, const char **value);
+apr_byte_t oidc_session_get(request_rec *r, oidc_session_t *z, const char *key, char **value);
 apr_byte_t oidc_session_set(request_rec *r, oidc_session_t *z, const char *key, const char *value);
 apr_byte_t oidc_session_save(request_rec *r, oidc_session_t *z, apr_byte_t first_time);
 apr_byte_t oidc_session_kill(request_rec *r, oidc_session_t *z);

src/oauth.c

@@ -689,6 +689,8 @@ int oidc_oauth_check_userid(request_rec *r, oidc_cfg *c, const char *access_toke
 		}
 	}
 
+	oidc_util_set_trace_parent(r, c, access_token);
+
 	/* validate the obtained access token against the OAuth AS validation endpoint */
 	json_t *token = NULL;
 	char *s_token = NULL;

src/parse.c

@@ -1119,6 +1119,27 @@ const char *oidc_parse_info_hook_data(apr_pool_t *pool, const char *arg, apr_has
 	return NULL;
 }
 
+#define OIDC_TRACE_PARENT_PROPAGATE_STR "propagate"
+#define OIDC_TRACE_PARENT_GENERATE_STR "generate"
+
+const char *valid_trace_parent_value(apr_pool_t *pool, const char *arg) {
+	static char *options[] = {OIDC_TRACE_PARENT_PROPAGATE_STR, OIDC_TRACE_PARENT_GENERATE_STR, NULL};
+	return oidc_valid_string_option(pool, arg, options);
+}
+
+const char *oidc_parse_trace_parent(apr_pool_t *pool, const char *arg, int *trace_parent) {
+	const char *rv = valid_trace_parent_value(pool, arg);
+	if (rv != NULL)
+		return rv;
+
+	if (_oidc_strcmp(arg, OIDC_TRACE_PARENT_PROPAGATE_STR) == 0)
+		*trace_parent = OIDC_TRACE_PARENT_PROPAGATE;
+	else if (_oidc_strcmp(arg, OIDC_TRACE_PARENT_GENERATE_STR) == 0)
+		*trace_parent = OIDC_TRACE_PARENT_GENERATE;
+
+	return NULL;
+}
+
 #define OIDC_AUTH_REQUEST_METHOD_GET_STR "GET"
 #define OIDC_AUTH_REQEUST_METHOD_POST_STR "POST"
 

src/parse.h

@@ -129,6 +129,7 @@ const char *oidc_parse_refresh_access_token_before_expiry(apr_pool_t *pool, cons
 const char *oidc_parse_set_state_input_headers_as(apr_pool_t *pool, const char *arg, apr_byte_t *state_input_headers);
 const char *oidc_parse_x_forwarded_headers(apr_pool_t *pool, const char *arg, apr_byte_t *x_forwarded_headers);
 const char *oidc_parse_outgoing_proxy_auth_type(apr_pool_t *pool, const char *arg, unsigned long *auth_type);
+const char *oidc_parse_trace_parent(apr_pool_t *pool, const char *arg, int *trace_parent);
 
 typedef const char *(*oidc_valid_int_function_t)(apr_pool_t *, int);
 typedef const char *(*oidc_valid_function_t)(apr_pool_t *, const char *);

src/session.c

@@ -105,9 +105,8 @@ void oidc_session_id_new(request_rec *r, oidc_session_t *z) {
  * clear contents of a session
  */
 static void oidc_session_clear(request_rec *r, oidc_session_t *z) {
-	z->uuid = NULL;
 	z->remote_user = NULL;
-	// NB: don't clear sid
+	// NB: don't clear sid or uuid
 	z->expiry = 0;
 	if (z->state) {
 		json_decref(z->state);
@@ -116,7 +115,7 @@ static void oidc_session_clear(request_rec *r, oidc_session_t *z) {
 }
 
 apr_byte_t oidc_session_load_cache_by_uuid(request_rec *r, oidc_cfg *c, const char *uuid, oidc_session_t *z) {
-	const char *stored_uuid = NULL;
+	char *stored_uuid = NULL;
 	char *s_json = NULL;
 	apr_byte_t rc = FALSE;
 
@@ -191,13 +190,6 @@ static apr_byte_t oidc_session_save_cache(request_rec *r, oidc_session_t *z, apr
 
 	if (z->state != NULL) {
 
-		if (z->uuid == NULL) {
-			/* get a new id for this session */
-			oidc_session_id_new(r, z);
-			/* store the session id in the cache value so it allows  us to detect cache corruption */
-			oidc_session_set(r, z, OIDC_SESSION_SESSION_ID, z->uuid);
-		}
-
 		if (z->sid != NULL) {
 			oidc_cache_set_sid(r, z->sid, z->uuid, z->expiry);
 			oidc_session_set(r, z, OIDC_SESSION_SID_KEY, z->sid);
@@ -282,6 +274,7 @@ apr_byte_t oidc_session_extract(request_rec *r, oidc_session_t *z) {
 
 	oidc_session_get(r, z, OIDC_SESSION_REMOTE_USER_KEY, &z->remote_user);
 	oidc_session_get(r, z, OIDC_SESSION_SID_KEY, &z->sid);
+	oidc_session_get(r, z, OIDC_SESSION_SESSION_ID, &z->uuid);
 
 	rc = TRUE;
 
@@ -301,6 +294,7 @@ apr_byte_t oidc_session_load(request_rec *r, oidc_session_t **zz) {
 	/* allocate space for the session object and fill it */
 	oidc_session_t *z = (*zz = apr_pcalloc(r->pool, sizeof(oidc_session_t)));
 	oidc_session_clear(r, z);
+	oidc_session_id_new(r, z);
 	z->sid = NULL;
 
 	if (c->session_type == OIDC_SESSION_TYPE_SERVER_CACHE)
@@ -316,6 +310,8 @@ apr_byte_t oidc_session_load(request_rec *r, oidc_session_t **zz) {
 	if (rc == TRUE)
 		rc = oidc_session_extract(r, z);
 
+	oidc_util_set_trace_parent(r, c, z->uuid);
+
 	return rc;
 }
 
@@ -330,6 +326,7 @@ apr_byte_t oidc_session_save(request_rec *r, oidc_session_t *z, apr_byte_t first
 	if (z->state != NULL) {
 		oidc_session_set(r, z, OIDC_SESSION_REMOTE_USER_KEY, z->remote_user);
 		json_object_set_new(z->state, OIDC_SESSION_EXPIRY_KEY, json_integer(apr_time_sec(z->expiry)));
+		oidc_session_set(r, z, OIDC_SESSION_SESSION_ID, z->uuid);
 	}
 
 	if (c->session_type == OIDC_SESSION_TYPE_SERVER_CACHE)
@@ -369,7 +366,7 @@ apr_byte_t oidc_session_kill(request_rec *r, oidc_session_t *z) {
 /*
  * get a value from the session based on the name from a name/value pair
  */
-apr_byte_t oidc_session_get(request_rec *r, oidc_session_t *z, const char *key, const char **value) {
+apr_byte_t oidc_session_get(request_rec *r, oidc_session_t *z, const char *key, char **value) {
 
 	/* just return the value for the key */
 	oidc_json_object_get_string(r->pool, z->state, key, (char **)value, NULL);
@@ -450,7 +447,7 @@ static json_t *oidc_session_get_str2json(request_rec *r, oidc_session_t *z,
 }
 
 static const char *oidc_session_get_key2string(request_rec *r, oidc_session_t *z, const char *key) {
-	const char *s_value = NULL;
+	char *s_value = NULL;
 	oidc_session_get(r, z, key, &s_value);
 	return s_value;
 }