1 files changed, 149 insertions, 0 deletions
diff --git a/src/lib-oauth2/oauth2.h b/src/lib-oauth2/oauth2.h
new file mode 100644
index 0000000..3d1d3ea
--- /dev/null
+++ b/src/lib-oauth2/oauth2.h
@@ -0,0 +1,149 @@
+#ifndef OAUTH2_H
+#define OAUTH2_H
+
+#include "net.h"
+
+struct dict;
+struct oauth2_request;
+struct oauth2_validation_key_cache;
+
+struct oauth2_field {
+	const char *name;
+	const char *value;
+};
+
+ARRAY_DEFINE_TYPE(oauth2_field, struct oauth2_field);
+
+struct oauth2_settings {
+	struct http_client *client;
+	/* GET tokeninfo from this URL, token is appended to URL
+	   http://some.host/path?access_token= */
+	const char *tokeninfo_url;
+	/* POST grant password here, needs user credentials and client_*
+	   settings */
+	const char *grant_url;
+	/* GET more information from this URL, uses Bearer authentication */
+	const char *introspection_url;
+	/* POST refresh here, needs refresh token and client_* settings */
+	const char *refresh_url;
+	/* client identificator for oauth2 server */
+	const char *client_id;
+	/* client secret for oauth2 server */
+	const char *client_secret;
+	/* access request scope for oauth2 server (optional) */
+	const char *scope;
+	/* key dict for looking up validation keys */
+	struct dict *key_dict;
+	/* cache for validation keys */
+	struct oauth2_validation_key_cache *key_cache;
+	/* valid issuer names */
+	const char *const *issuers;
+
+	enum {
+		INTROSPECTION_MODE_GET_AUTH,
+		INTROSPECTION_MODE_GET,
+		INTROSPECTION_MODE_POST,
+		INTROSPECTION_MODE_LOCAL,
+	} introspection_mode;
+	unsigned int timeout_msecs;
+	/* Should X-Dovecot-Auth-* headers be sent */
+	bool send_auth_headers;
+	/* Should use grant password mechanism for authentication */
+	bool use_grant_password;
+};
+
+
+struct oauth2_request_result {
+	/* Oauth2 server response fields */
+	ARRAY_TYPE(oauth2_field) *fields;
+	/* Non-NULL if there was an unexpected internal error. */
+	const char *error;
+	/* timestamp token expires at */
+	time_t expires_at;
+	/* User authenticated successfully. Implies that error==NULL. */
+	bool valid:1;
+};
+
+struct oauth2_request_input {
+	const char *token;
+	const char *service;
+	struct ip_addr local_ip, real_local_ip, remote_ip, real_remote_ip;
+	in_port_t local_port, real_local_port, remote_port, real_remote_port;
+};
+
+typedef void
+oauth2_request_callback_t(struct oauth2_request_result*, void*);
+
+bool oauth2_valid_token(const char *token);
+
+struct oauth2_request*
+oauth2_passwd_grant_start(const struct oauth2_settings *set,
+			  const struct oauth2_request_input *input,
+			  const char *username,
+			  const char *password,
+			  oauth2_request_callback_t *callback,
+			  void *context);
+#define oauth2_passwd_grant_start(set, input, username, password, callback, \
+				  context) \
+	oauth2_passwd_grant_start( \
+		set, input - CALLBACK_TYPECHECK( \
+			callback, void(*)(struct oauth2_request_result*, \
+					  typeof(context))), \
+		username, password, \
+		(oauth2_request_callback_t*)callback, (void*)context);
+
+struct oauth2_request*
+oauth2_token_validation_start(const struct oauth2_settings *set,
+			      const struct oauth2_request_input *input,
+			      oauth2_request_callback_t *callback,
+			      void *context);
+#define oauth2_token_validation_start(set, input, callback, context) \
+	oauth2_token_validation_start( \
+		set, input - CALLBACK_TYPECHECK( \
+			callback, void(*)(struct oauth2_request_result*, \
+					  typeof(context))), \
+		(oauth2_request_callback_t*)callback, (void*)context);
+
+struct oauth2_request*
+oauth2_introspection_start(const struct oauth2_settings *set,
+			   const struct oauth2_request_input *input,
+			   oauth2_request_callback_t *callback,
+			   void *context);
+#define oauth2_introspection_start(set, input, callback, context) \
+	oauth2_introspection_start( \
+		set, input - CALLBACK_TYPECHECK( \
+			callback, void(*)(struct oauth2_request_result*, \
+					  typeof(context))), \
+		(oauth2_request_callback_t*)callback, (void*)context);
+
+struct oauth2_request *
+oauth2_refresh_start(const struct oauth2_settings *set,
+		     const struct oauth2_request_input *input,
+		     oauth2_request_callback_t *callback,
+		     void *context);
+#define oauth2_refresh_start(set, input, callback, context) \
+	oauth2_refresh_start( \
+		set, input - CALLBACK_TYPECHECK( \
+			callback, void(*)(struct oauth2_request_result*, \
+					  typeof(context))), \
+		(oauth2_request_callback_t*)callback, (void*)context);
+
+/* Abort without calling callback, use this to cancel the request */
+void oauth2_request_abort(struct oauth2_request **);
+
+int oauth2_try_parse_jwt(const struct oauth2_settings *set,
+			 const char *token, ARRAY_TYPE(oauth2_field) *fields,
+			 bool *is_jwt_r, const char **error_r);
+
+/* Initialize validation key cache */
+struct oauth2_validation_key_cache *oauth2_validation_key_cache_init(void);
+
+/* Evict given key ID from cache, returns 0 on successful eviction */
+int oauth2_validation_key_cache_evict(struct oauth2_validation_key_cache *cache,
+				      const char *key_id);
+
+/* Deinitialize validation key cache */
+void oauth2_validation_key_cache_deinit(
+	struct oauth2_validation_key_cache **_cache);
+
+#endif