dnl ** Shared libraries usage
dnl **
-LIBDOVECOT_LA_LIBS='$(top_builddir)/src/lib-dict-extra/libdict_extra.la $(top_builddir)/src/lib-program-client/libprogram_client.la $(top_builddir)/src/lib-master/libmaster.la $(top_builddir)/src/lib-settings/libsettings.la $(top_builddir)/src/lib-stats/libstats.la $(top_builddir)/src/lib-http/libhttp.la $(top_builddir)/src/lib-fs/libfs.la $(top_builddir)/src/lib-dict/libdict.la $(top_builddir)/src/lib-smtp/libsmtp.la $(top_builddir)/src/lib-dns/libdns.la $(top_builddir)/src/lib-imap/libimap.la $(top_builddir)/src/lib-mail/libmail.la $(top_builddir)/src/lib-sasl/libsasl.la $(top_builddir)/src/lib-auth/libauth.la $(top_builddir)/src/lib-charset/libcharset.la $(top_builddir)/src/lib-ssl-iostream/libssl_iostream.la $(top_builddir)/src/lib-dcrypt/libdcrypt.la $(top_builddir)/src/lib-test/libtest.la $(top_builddir)/src/lib/liblib.la'
+LIBDOVECOT_LA_LIBS='$(top_builddir)/src/lib-dict-extra/libdict_extra.la $(top_builddir)/src/lib-oauth2/liboauth2.la $(top_builddir)/src/lib-program-client/libprogram_client.la $(top_builddir)/src/lib-master/libmaster.la $(top_builddir)/src/lib-settings/libsettings.la $(top_builddir)/src/lib-stats/libstats.la $(top_builddir)/src/lib-http/libhttp.la $(top_builddir)/src/lib-fs/libfs.la $(top_builddir)/src/lib-dict/libdict.la $(top_builddir)/src/lib-smtp/libsmtp.la $(top_builddir)/src/lib-dns/libdns.la $(top_builddir)/src/lib-imap/libimap.la $(top_builddir)/src/lib-mail/libmail.la $(top_builddir)/src/lib-sasl/libsasl.la $(top_builddir)/src/lib-auth/libauth.la $(top_builddir)/src/lib-charset/libcharset.la $(top_builddir)/src/lib-ssl-iostream/libssl_iostream.la $(top_builddir)/src/lib-dcrypt/libdcrypt.la $(top_builddir)/src/lib-test/libtest.la $(top_builddir)/src/lib/liblib.la'
if test "$want_shared_libs" = "yes"; then
LIBDOVECOT_DEPS='$(top_builddir)/src/lib-dovecot/libdovecot.la'
LIBDOVECOT="$LIBDOVECOT_DEPS \$(MODULE_LIBS)"
src/lib-fs/Makefile
src/lib-fts/Makefile
src/lib-http/Makefile
+src/lib-oauth2/Makefile
src/lib-imap/Makefile
src/lib-imap-storage/Makefile
src/lib-imap-client/Makefile
lib-smtp \
lib-imap \
lib-imap-storage \
- lib-program-client
+ lib-program-client \
+ lib-oauth2
SUBDIRS = \
$(LIBDOVECOT_SUBDIRS) \
--- /dev/null
+AM_CPPFLAGS = \
+ -I$(top_srcdir)/src/lib \
+ -I$(top_srcdir)/src/lib-http \
+ -I$(top_srcdir)/src/lib-settings
+
+noinst_LTLIBRARIES=liboauth2.la
+
+pkginc_libdir=$(pkgincludedir)
+pkginc_lib_HEADERS = \
+ oauth2.h
+
+noinst_HEADERS = \
+ oauth2-private.h
+
+liboauth2_la_SOURCES = \
+ oauth2.c \
+ oauth2-token-validate.c \
+ oauth2-introspect.c \
+ oauth2-refresh.c
+
+check_programs = \
+ oauth2-server \
+ test-oauth2
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "str.h"
+#include "ioloop.h"
+#include "istream.h"
+#include "http-client.h"
+#include "http-url.h"
+#include "json-parser.h"
+#include "oauth2.h"
+#include "oauth2-private.h"
+
+static void
+oauth2_introspection_callback(struct oauth2_request *req,
+ struct oauth2_introspection_result *res)
+{
+ i_assert(res->success == (res->error == NULL));
+ i_assert(req->is_callback != NULL);
+ oauth2_introspection_callback_t *callback = req->is_callback;
+ req->is_callback = NULL;
+ callback(res, req->is_context);
+ oauth2_request_free_internal(req);
+}
+
+static void
+oauth2_introspect_continue(struct oauth2_request *req, bool success,
+ const char *error)
+{
+ struct oauth2_introspection_result res;
+ i_zero(&res);
+
+ res.success = success;
+ res.error = error;
+ res.fields = &req->fields;
+
+ oauth2_introspection_callback(req, &res);
+}
+
+static void
+oauth2_introspect_response(const struct http_response *response,
+ struct oauth2_request *req)
+{
+ if (response->status / 100 != 2) {
+ oauth2_introspect_continue(req, FALSE, response->reason);
+ } else {
+ if (response->payload == NULL) {
+ oauth2_introspect_continue(req, FALSE, "Missing response body");
+ return;
+ }
+ req->is = response->payload;
+ i_stream_ref(req->is);
+ req->parser = json_parser_init(req->is);
+ req->json_parsed_cb = oauth2_introspect_continue;
+ req->io = io_add_istream(req->is, oauth2_parse_json, req);
+ oauth2_parse_json(req);
+ }
+}
+
+#undef oauth2_introspection_start
+struct oauth2_request*
+oauth2_introspection_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_introspection_callback_t *callback,
+ void *context)
+{
+ i_assert(oauth2_valid_token(input->token));
+
+ pool_t pool = pool_alloconly_create_clean("oauth2 introspection", 1024);
+ struct oauth2_request *req =
+ p_new(pool, struct oauth2_request, 1);
+ struct oauth2_introspection_result fail = {
+ .success = FALSE,
+ };
+ struct http_url *url;
+ const char *error;
+
+ req->pool = pool;
+ req->set = set;
+ req->is_callback = callback;
+ req->is_context = context;
+
+ string_t *enc = t_str_new(64);
+ str_append(enc, req->set->introspection_url);
+
+ if (set->introspection_mode == INTROSPECTION_MODE_GET) {
+ http_url_escape_param(enc, input->token);
+ }
+
+ if (http_url_parse(str_c(enc), NULL, 0, pool, &url, &error) < 0) {
+ fail.error = t_strdup_printf("http_url_parse(%s) failed: %s",
+ str_c(enc), error);
+ oauth2_introspection_callback(req, &fail);
+ return req;
+ }
+
+ if (set->introspection_mode == INTROSPECTION_MODE_POST) {
+ req->req = http_client_request_url(req->set->client, "POST", url,
+ oauth2_introspect_response,
+ req);
+ /* add token */
+ enc = t_str_new(strlen(input->token)+6);
+ str_append(enc, "token=");
+ http_url_escape_param(enc, input->token);
+ http_client_request_set_payload_data(req->req, enc->data, enc->used);
+ } else {
+ req->req = http_client_request_url(req->set->client, "GET", url,
+ oauth2_introspect_response,
+ req);
+ }
+
+ if (set->introspection_mode == INTROSPECTION_MODE_GET_AUTH)
+ http_client_request_add_header(req->req,
+ "Authorization",
+ t_strdup_printf("Bearer %s",
+ input->token));
+
+ oauth2_request_set_headers(req, input);
+
+ http_client_request_set_timeout_msecs(req->req,
+ req->set->timeout_msecs);
+ http_client_request_submit(req->req);
+
+ return req;
+}
+
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+#ifndef OAUTH2_PRIVATE_H
+#define OAUTH2_PRIVATE_H 1
+
+struct oauth2_request {
+ pool_t pool;
+
+ const struct oauth2_settings *set;
+ struct http_client_request *req;
+ struct json_parser *parser;
+ struct istream *is;
+ struct io *io;
+
+ const char *username;
+
+ void (*json_parsed_cb)(struct oauth2_request*, bool success,
+ const char *error);
+
+ ARRAY_TYPE(oauth2_field) fields;
+ char *field_name;
+
+ oauth2_token_validation_callback_t *tv_callback;
+ void *tv_context;
+
+ oauth2_introspection_callback_t *is_callback;
+ void *is_context;
+
+ oauth2_refresh_callback_t *re_callback;
+ void *re_context;
+
+ /* indicates whether token is valid */
+ bool valid:1;
+};
+
+void oauth2_request_set_headers(struct oauth2_request *req,
+ const struct oauth2_request_input *input);
+
+void oauth2_request_free_internal(struct oauth2_request *req);
+
+void oauth2_parse_json(struct oauth2_request *req);
+
+#endif
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "ioloop.h"
+#include "istream.h"
+#include "str.h"
+#include "http-client.h"
+#include "http-url.h"
+#include "json-parser.h"
+#include "oauth2.h"
+#include "oauth2-private.h"
+
+static void
+oauth2_refresh_callback(struct oauth2_request *req,
+ struct oauth2_refresh_result *res)
+{
+ i_assert(res->success == (res->error == NULL));
+ i_assert(req->re_callback != NULL);
+ oauth2_refresh_callback_t *callback = req->re_callback;
+ req->re_callback = NULL;
+ callback(res, req->re_context);
+ oauth2_request_free_internal(req);
+}
+
+static bool
+oauth2_refresh_field_parse(const struct oauth2_field *field,
+ struct oauth2_refresh_result *res)
+{
+ if (strcasecmp(field->name, "expires_in") == 0) {
+ uint32_t expires_in = 0;
+ if (str_to_uint32(field->value, &expires_in) < 0) {
+ res->success = FALSE;
+ res->error = t_strdup_printf(
+ "Malformed number '%s' in expires_in",
+ field->value);
+ return FALSE;
+ } else {
+ res->expires_at = ioloop_time + expires_in;
+ }
+ } else if (strcasecmp(field->name, "token_type") == 0) {
+ if (strcasecmp(field->value,"bearer") != 0) {
+ res->success = FALSE;
+ res->error = t_strdup_printf(
+ "Expected Bearer token, got '%s'",
+ field->value);
+ return FALSE;
+ }
+ } else if (strcasecmp(field->name, "access_token") == 0) {
+ /* pooled memory */
+ res->bearer_token = field->value;
+ }
+ return TRUE;
+}
+
+static void
+oauth2_refresh_continue(struct oauth2_request *req, bool success,
+ const char *error)
+{
+ struct oauth2_refresh_result res;
+ i_zero(&res);
+
+ res.success = success;
+ res.error = error;
+
+ if (res.success) {
+ const struct oauth2_field *field;
+ /* see if we can figure out when it expires */
+ array_foreach(&req->fields, field) {
+ if (!oauth2_refresh_field_parse(field, &res))
+ break;
+ }
+ }
+
+ res.fields = &req->fields;
+
+ oauth2_refresh_callback(req, &res);
+}
+
+static void
+oauth2_refresh_response(const struct http_response *response,
+ struct oauth2_request *req)
+{
+ if (response->status / 100 != 2) {
+ oauth2_refresh_continue(req, FALSE, response->reason);
+ } else {
+ if (response->payload == NULL) {
+ oauth2_refresh_continue(req, FALSE, "Missing response body");
+ return;
+ }
+ req->is = response->payload;
+ i_stream_ref(req->is);
+ req->parser = json_parser_init(req->is);
+ req->json_parsed_cb = oauth2_refresh_continue;
+ req->io = io_add_istream(req->is, oauth2_parse_json, req);
+ oauth2_parse_json(req);
+ }
+}
+
+#undef oauth2_refresh_start
+struct oauth2_request*
+oauth2_refresh_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_refresh_callback_t *callback,
+ void *context)
+{
+ i_assert(oauth2_valid_token(input->token));
+
+ pool_t pool = pool_alloconly_create_clean("oauth2 refresh", 1024);
+ struct oauth2_request *req =
+ p_new(pool, struct oauth2_request, 1);
+ struct http_url *url;
+ const char *error;
+ struct oauth2_refresh_result fail = {
+ .success = FALSE
+ };
+
+ req->pool = pool;
+ req->set = set;
+ req->re_callback = callback;
+ req->re_context = context;
+
+ const char *_url = req->set->refresh_url;
+
+ if (http_url_parse(_url, NULL, 0, pool, &url, &error) < 0) {
+ fail.error = t_strdup_printf("http_url_parse(%s) failed: %s",
+ _url, error);
+ oauth2_refresh_callback(req, &fail);
+ return req;
+ }
+
+ req->req = http_client_request_url(req->set->client, "POST", url,
+ oauth2_refresh_response,
+ req);
+ string_t *payload = str_new(req->pool, 128);
+ str_append(payload, "client_secret=");
+ http_url_escape_param(payload, req->set->client_secret);
+ str_append(payload, "&grant_type=refresh_token&refresh_token=");
+ http_url_escape_param(payload, input->token);
+ str_append(payload, "&client_id=");
+ http_url_escape_param(payload, req->set->client_id);
+
+ struct istream *is = i_stream_create_from_string(payload);
+
+ http_client_request_add_header(req->req, "Content-Type",
+ "application/x-www-form-urlencoded");
+
+ oauth2_request_set_headers(req, input);
+
+ http_client_request_set_payload(req->req, is, FALSE);
+ i_stream_unref(&is);
+ http_client_request_set_timeout_msecs(req->req,
+ req->set->timeout_msecs);
+ http_client_request_submit(req->req);
+
+ return req;
+}
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "str.h"
+#include "ioloop.h"
+#include "istream.h"
+#include "strnum.h"
+#include "http-client.h"
+#include "http-url.h"
+#include "json-parser.h"
+#include "oauth2.h"
+#include "oauth2-private.h"
+
+static void
+oauth2_token_validation_callback(struct oauth2_request *req,
+ struct oauth2_token_validation_result *res)
+{
+ i_assert(res->success == (res->error == NULL));
+ i_assert(req->tv_callback != NULL);
+ oauth2_token_validation_callback_t *callback = req->tv_callback;
+ req->tv_callback = NULL;
+ callback(res, req->tv_context);
+ oauth2_request_free_internal(req);
+}
+
+static void
+oauth2_token_validate_continue(struct oauth2_request *req, bool success,
+ const char *error)
+{
+ struct oauth2_token_validation_result res;
+ i_zero(&res);
+
+ res.success = success;
+ res.error = error;
+ res.valid = req->valid;
+
+ if (res.success) {
+ const struct oauth2_field *field;
+ /* see if we can figure out when it expires */
+ array_foreach(&req->fields, field) {
+ if (strcasecmp(field->name, "expires_in") == 0) {
+ uint32_t expires_in = 0;
+ if (str_to_uint32(field->value, &expires_in) < 0) {
+ res.success = FALSE;
+ res.error = "Malformed number in expires_in";
+ } else {
+ res.expires_at = ioloop_time + expires_in;
+ }
+ break;
+ }
+ }
+ }
+
+ res.fields = &req->fields;
+
+ oauth2_token_validation_callback(req, &res);
+}
+
+static void
+oauth2_token_validate_response(const struct http_response *response,
+ struct oauth2_request *req)
+{
+ unsigned int status_1 = response->status / 100;
+
+ if (status_1 != 2 && status_1 != 4) {
+ oauth2_token_validate_continue(req, FALSE, response->reason);
+ } else {
+ if (status_1 == 2)
+ req->valid = TRUE;
+ else
+ req->valid = FALSE;
+ /* 2xx is sufficient for token validation */
+ if (response->payload == NULL) {
+ p_array_init(&req->fields, req->pool, 1);
+ oauth2_token_validate_continue(req, TRUE, NULL);
+ return;
+ }
+ req->is = response->payload;
+ i_stream_ref(req->is);
+ req->parser = json_parser_init(req->is);
+ req->json_parsed_cb = oauth2_token_validate_continue;
+ req->io = io_add_istream(req->is, oauth2_parse_json, req);
+ oauth2_parse_json(req);
+ }
+}
+
+#undef oauth2_token_validation_start
+struct oauth2_request*
+oauth2_token_validation_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_token_validation_callback_t *callback,
+ void *context)
+{
+ i_assert(oauth2_valid_token(input->token));
+
+ struct http_url *url;
+ const char *error;
+ struct oauth2_token_validation_result fail = {
+ .success = FALSE
+ };
+
+ pool_t pool = pool_alloconly_create_clean("oauth2 token_validation", 1024);
+ struct oauth2_request *req =
+ p_new(pool, struct oauth2_request, 1);
+
+ req->pool = pool;
+ req->set = set;
+ req->tv_callback = callback;
+ req->tv_context = context;
+
+ string_t *enc = t_str_new(64);
+ str_append(enc, req->set->tokeninfo_url);
+ http_url_escape_param(enc, input->token);
+
+ if (http_url_parse(str_c(enc), NULL, 0, pool, &url, &error) < 0) {
+ fail.error = t_strdup_printf("http_url_parse(%s) failed: %s",
+ str_c(enc), error);
+ oauth2_token_validation_callback(req, &fail);
+ return req;
+ }
+
+ req->req = http_client_request_url(req->set->client, "GET", url,
+ oauth2_token_validate_response,
+ req);
+ http_client_request_add_header(req->req,
+ "Authorization",
+ t_strdup_printf("Bearer %s",
+ input->token));
+
+ oauth2_request_set_headers(req, input);
+
+ http_client_request_set_timeout_msecs(req->req,
+ req->set->timeout_msecs);
+ http_client_request_submit(req->req);
+
+ return req;
+}
+
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "ioloop.h"
+#include "istream.h"
+#include "http-client.h"
+#include "json-parser.h"
+#include "oauth2.h"
+#include "oauth2-private.h"
+#include "safe-memset.h"
+
+void
+oauth2_parse_json(struct oauth2_request *req)
+{
+ bool success;
+ enum json_type type;
+ const char *token, *error;
+ int ret;
+
+ req->field_name = NULL;
+
+ while((ret = json_parse_next(req->parser, &type, &token)) > 0) {
+ if (req->field_name == NULL) {
+ if (type != JSON_TYPE_OBJECT_KEY) break;
+ /* cannot use t_strdup because we might
+ have to read more */
+ req->field_name = p_strdup(req->pool, token);
+ } else if (type < JSON_TYPE_STRING) {
+ /* this should be last allocation */
+ p_free(req->pool, req->field_name);
+ json_parse_skip_next(req->parser);
+ } else {
+ if (!array_is_created(&req->fields))
+ p_array_init(&req->fields, req->pool, 4);
+ struct oauth2_field *field =
+ array_append_space(&req->fields);
+ field->name = req->field_name;
+ req->field_name = NULL;
+ field->value = p_strdup(req->pool, token);
+ }
+ }
+
+ /* read more */
+ if (ret == 0) return;
+
+ io_remove(&req->io);
+
+ if (ret > 0) {
+ (void)json_parser_deinit(&req->parser, &error);
+ error = "Invalid response data";
+ success = FALSE;
+ } else {
+ ret = json_parser_deinit(&req->parser, &error);
+ success = (ret == 0);
+ }
+
+ i_stream_unref(&req->is);
+
+ req->json_parsed_cb(req, success, error);
+}
+
+void
+oauth2_request_abort(struct oauth2_request **_req)
+{
+ struct oauth2_request *req = *_req;
+ *_req = NULL;
+
+ if (req->req != NULL)
+ http_client_request_abort(&req->req);
+ oauth2_request_free_internal(req);
+}
+
+void
+oauth2_request_free_internal(struct oauth2_request *req)
+{
+ pool_unref(&req->pool);
+}
+
+bool oauth2_valid_token(const char *token)
+{
+ if (token == NULL || *token == '\0' || strpbrk(token, "\r\n") != NULL)
+ return FALSE;
+ return TRUE;
+}
+
+void oauth2_request_set_headers(struct oauth2_request *req,
+ const struct oauth2_request_input *input)
+{
+ if (!req->set->send_auth_headers)
+ return;
+ if (input->service != NULL) {
+ http_client_request_add_header(req->req, "X-Dovecot-Auth-Service",
+ input->service);
+ }
+ if (input->local_ip.family != 0) {
+ const char *addr;
+ if (net_ipport2str(&input->local_ip, input->local_port, &addr) == 0)
+ http_client_request_add_header(req->req, "X-Dovecot-Auth-Local", addr);
+ }
+ if (input->remote_ip.family != 0) {
+ const char *addr;
+ if (net_ipport2str(&input->remote_ip, input->remote_port, &addr) == 0)
+ http_client_request_add_header(req->req, "X-Dovecot-Auth-Remote", addr);
+ }
+}
--- /dev/null
+/* Copyright (c) 2017 Dovecot authors, see the included COPYING file */
+#ifndef OAUTH2_H
+#define OAUTH2_H
+
+#include "net.h"
+
+struct oauth2_request;
+
+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;
+ /* 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;
+ const char *client_id;
+ const char *client_secret;
+ enum {
+ INTROSPECTION_MODE_GET_AUTH,
+ INTROSPECTION_MODE_GET,
+ INTROSPECTION_MODE_POST
+ } introspection_mode;
+ unsigned int timeout_msecs;
+ /* Should X-Dovecot-Auth-* headers be sent */
+ bool send_auth_headers;
+};
+
+struct oauth2_token_validation_result {
+ ARRAY_TYPE(oauth2_field) *fields;
+ const char *error;
+ time_t expires_at;
+ bool success:1;
+ bool valid:1;
+};
+
+struct oauth2_introspection_result {
+ ARRAY_TYPE(oauth2_field) *fields;
+ const char *error;
+ bool success:1;
+};
+
+struct oauth2_refresh_result {
+ ARRAY_TYPE(oauth2_field) *fields;
+ const char *bearer_token;
+ const char *error;
+ time_t expires_at;
+ bool success: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_token_validation_callback_t(struct oauth2_token_validation_result*, void*);
+
+typedef void
+oauth2_introspection_callback_t(struct oauth2_introspection_result*, void*);
+
+typedef void
+oauth2_refresh_callback_t(struct oauth2_refresh_result*, void*);
+
+bool oauth2_valid_token(const char *token);
+
+struct oauth2_request*
+oauth2_token_validation_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_token_validation_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_token_validation_result*, typeof(context))), \
+ (oauth2_token_validation_callback_t*)callback, (void*)context);
+
+struct oauth2_request*
+oauth2_introspection_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_introspection_callback_t *callback,
+ void *context);
+#define oauth2_introspection_start(set, input, callback, context) \
+ oauth2_introspection_start(set, input + \
+ CALLBACK_TYPECHECK(callback, void(*)(struct oauth2_introspection_result*, typeof(context))), \
+ (oauth2_introspection_callback_t*)callback, (void*)context);
+
+struct oauth2_request*
+oauth2_refresh_start(const struct oauth2_settings *set,
+ const struct oauth2_request_input *input,
+ oauth2_refresh_callback_t *callback,
+ void *context);
+#define oauth2_refresh_start(set, input, callback, context) \
+ oauth2_refresh_start(set, input + \
+ CALLBACK_TYPECHECK(callback, void(*)(struct oauth2_refresh_result*, typeof(context))), \
+ (oauth2_refresh_callback_t*)callback, (void*)context);
+
+/* abort without calling callback, use this to cancel the request */
+void oauth2_request_abort(struct oauth2_request **);
+
+#endif