/* Copyright (C) 2002-2004 Timo Sirainen */

#include "common.h"

#include "base64.h"

#include "buffer.h"

#include "str-sanitize.h"

#include "auth-client.h"

#include "ssl-proxy.h"

#include "client-common.h"

#include "master.h"

static enum auth_request_flags

client_get_auth_flags(struct client *client)

{

        enum auth_request_flags auth_flags = 0;

	if (client->proxy != NULL &&

	    ssl_proxy_has_valid_client_cert(client->proxy))

		auth_flags |= AUTH_REQUEST_FLAG_VALID_CLIENT_CERT;

	if (client->secured)

		auth_flags |= AUTH_REQUEST_FLAG_SECURED;

	return auth_flags;

}

static void

call_client_callback(struct client *client, enum sasl_server_reply reply,

		     const char *data, const char *const *args)

{

	sasl_server_callback_t *sasl_callback;

	i_assert(reply != SASL_SERVER_REPLY_CONTINUE);

	sasl_callback = client->sasl_callback;

	client->sasl_callback = NULL;

	sasl_callback(client, reply, data, args);

	/* NOTE: client may be destroyed now */

}

static void master_callback(struct client *client, bool success)

{

	client->authenticating = FALSE;

	call_client_callback(client, success ? SASL_SERVER_REPLY_SUCCESS :

			     SASL_SERVER_REPLY_MASTER_FAILED, NULL, NULL);

}

static void authenticate_callback(struct auth_request *request, int status,

				  const char *data_base64,

				  const char *const *args, void *context)

{

	struct client *client = context;

	unsigned int i;

	bool nologin;

	if (!client->authenticating) {

		/* client aborted */

		i_assert(status < 0);

		return;

	}

	i_assert(client->auth_request == request);

	client->waiting_auth_reply = FALSE;

	switch (status) {

	case 0:

		/* continue */

		client->sasl_callback(client, SASL_SERVER_REPLY_CONTINUE,

				      data_base64, NULL);

		break;

	case 1:

		client->auth_request = NULL;

		nologin = FALSE;

		for (i = 0; args[i] != NULL; i++) {

			if (strncmp(args[i], "user=", 5) == 0) {

				i_free(client->virtual_user);

				client->virtual_user = i_strdup(args[i] + 5);

			}

			if (strcmp(args[i], "nologin") == 0 ||

			    strcmp(args[i], "proxy") == 0) {

				/* user can't login */

				nologin = TRUE;

			}

		}

		if (nologin) {

			client->authenticating = FALSE;

			call_client_callback(client, SASL_SERVER_REPLY_SUCCESS,

					     NULL, args);

		} else {

			master_request_login(client, master_callback,

				auth_client_request_get_server_pid(request),

				auth_client_request_get_id(request));

		}

		break;

	case -1:

		client->auth_request = NULL;

		if (args != NULL) {

			/* parse our username if it's there */

			for (i = 0; args[i] != NULL; i++) {

				if (strncmp(args[i], "user=", 5) == 0) {

					i_free(client->virtual_user);

					client->virtual_user =

						i_strdup(args[i] + 5);

				}

			}

		}

		client->authenticating = FALSE;

		call_client_callback(client, SASL_SERVER_REPLY_AUTH_FAILED,

				     NULL, args);

		break;

	}

}

void sasl_server_auth_begin(struct client *client,

			    const char *service, const char *mech_name,

			    const char *initial_resp_base64,

			    sasl_server_callback_t *callback)

{

	struct auth_request_info info;

	const struct auth_mech_desc *mech;

	const char *error;

	client->authenticating = TRUE;

	i_free(client->auth_mech_name);

	client->auth_mech_name = str_ucase(i_strdup(mech_name));

	client->sasl_callback = callback;

	mech = auth_client_find_mech(auth_client, mech_name);

	if (mech == NULL) {

		sasl_server_auth_failed(client,

			"Unsupported authentication mechanism.");

		return;

	}

	if (!client->secured && disable_plaintext_auth &&

	    (mech->flags & MECH_SEC_PLAINTEXT) != 0) {

		sasl_server_auth_failed(client,

			"Plaintext authentication disabled.");

		return;

	}

	memset(&info, 0, sizeof(info));

	info.mech = mech->name;

	info.service = service;

	info.cert_username = client->proxy == NULL ? NULL :

		ssl_proxy_get_peer_name(client->proxy);

	info.flags = client_get_auth_flags(client);

	info.local_ip = client->local_ip;

	info.remote_ip = client->ip;

	info.initial_resp_base64 = initial_resp_base64;

	client->auth_request =

		auth_client_request_new(auth_client, NULL, &info,

					authenticate_callback, client, &error);

	if (client->auth_request == NULL) {

		sasl_server_auth_failed(client,

			 t_strconcat("Authentication failed: ", error, NULL));

	}

}

static void sasl_server_auth_cancel(struct client *client, const char *reason,

				    enum sasl_server_reply reply)

{

	i_assert(client->authenticating);

	if (verbose_auth && reason != NULL) {

		const char *auth_name =

			str_sanitize(client->auth_mech_name, MAX_MECH_NAME);

		client_syslog(client,

			t_strdup_printf("Authenticate %s failed: %s",

					auth_name, reason));

	}

	client->authenticating = FALSE;

	client->waiting_auth_reply = FALSE;

	if (client->auth_request != NULL) {

		auth_client_request_abort(client->auth_request);

		client->auth_request = NULL;

	}

	call_client_callback(client, reply, reason, NULL);

}

void sasl_server_auth_failed(struct client *client, const char *reason)

{

	sasl_server_auth_cancel(client, reason, SASL_SERVER_REPLY_AUTH_FAILED);

}

void sasl_server_auth_client_error(struct client *client, const char *reason)

{

	sasl_server_auth_cancel(client, reason, SASL_SERVER_REPLY_CLIENT_ERROR);

}