IABSD.fr/src/usr.sbin/radiusd/radiusd.c

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• Author : deraadt
  Date : 2019-06-28 13:32:41
  Hash : df69c215
  Message : When system calls indicate an error they return -1, not some arbitrary value < 0. errno is only updated in this case. Change all (most?) callers of syscalls to follow this better, and let's see if this strictness helps us in the future.

• usr.sbin/radiusd/radiusd.c

• /*	$OpenBSD: radiusd.c,v 1.27 2019/06/28 13:32:49 deraadt Exp $	*/
  
  /*
   * Copyright (c) 2013 Internet Initiative Japan Inc.
   *
   * Permission to use, copy, modify, and distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  #include <sys/types.h>
  #include <sys/socket.h>
  #include <sys/queue.h>
  #include <sys/uio.h>
  #include <sys/wait.h>
  #include <netinet/in.h>
  
  #include <dlfcn.h>
  #include <err.h>
  #include <errno.h>
  #include <event.h>
  #include <fcntl.h>
  #include <fnmatch.h>
  #include <imsg.h>
  #include <md5.h>
  #include <netdb.h>
  #include <pwd.h>
  #include <signal.h>
  #include <stdbool.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <syslog.h>
  #include <unistd.h>
  #include <util.h>
  
  #include <radius.h>
  
  #include "radiusd.h"
  #include "radiusd_local.h"
  #include "log.h"
  #include "util.h"
  #include "imsg_subr.h"
  
  static int		 radiusd_start(struct radiusd *);
  static void		 radiusd_stop(struct radiusd *);
  static void		 radiusd_free(struct radiusd *);
  static void		 radiusd_listen_on_event(int, short, void *);
  static void		 radiusd_on_sigterm(int, short, void *);
  static void		 radiusd_on_sigint(int, short, void *);
  static void		 radiusd_on_sighup(int, short, void *);
  static void		 radiusd_on_sigchld(int, short, void *);
  static int		 radius_query_request_decoration(struct radius_query *);
  static int		 radius_query_response_decoration(
  			    struct radius_query *);
  static const char	*radius_code_string(int);
  static int		 radiusd_access_response_fixup (struct radius_query *);
  
  
  
  static void		 radiusd_module_reset_ev_handler(
  			    struct radiusd_module *);
  static int		 radiusd_module_imsg_read(struct radiusd_module *,
  			    bool);
  static void		 radiusd_module_imsg(struct radiusd_module *,
  			    struct imsg *);
  
  static struct radiusd_module_radpkt_arg *
  			 radiusd_module_recv_radpkt(struct radiusd_module *,
  			    struct imsg *, uint32_t, const char *);
  static void		 radiusd_module_on_imsg_io(int, short, void *);
  void			 radiusd_module_start(struct radiusd_module *);
  void			 radiusd_module_stop(struct radiusd_module *);
  static void		 radiusd_module_close(struct radiusd_module *);
  static void		 radiusd_module_userpass(struct radiusd_module *,
  			    struct radius_query *);
  static void		 radiusd_module_access_request(struct radiusd_module *,
  			    struct radius_query *);
  
  static u_int		 radius_query_id_seq = 0;
  int			 debug = 0;
  
  static __dead void
  usage(void)
  {
  	extern char *__progname;
  
  	fprintf(stderr, "usage: %s [-dn] [-f file]\n", __progname);
  	exit(EXIT_FAILURE);
  }
  
  int
  main(int argc, char *argv[])
  {
  	extern char		*__progname;
  	const char		*conffile = CONFFILE;
  	int			 ch;
  	struct radiusd		*radiusd;
  	bool			 noaction = false;
  	struct passwd		*pw;
  
  	while ((ch = getopt(argc, argv, "df:n")) != -1)
  		switch (ch) {
  		case 'd':
  			debug++;
  			break;
  
  		case 'f':
  			conffile = optarg;
  			break;
  
  		case 'n':
  			noaction = true;
  			break;
  
  		default:
  			usage();
  			/* NOTREACHED */
  		}
  
  	argc -= optind;
  	argv += optind;
  
  	if (argc != 0)
  		usage();
  
  	if ((radiusd = calloc(1, sizeof(*radiusd))) == NULL)
  		err(1, "calloc");
  	TAILQ_INIT(&radiusd->listen);
  	TAILQ_INIT(&radiusd->query);
  
  	log_init(debug);
  	if (parse_config(conffile, radiusd) != 0)
  		errx(EXIT_FAILURE, "config error");
  	if (noaction) {
  		fprintf(stderr, "configuration OK\n");
  		exit(EXIT_SUCCESS);
  	}
  
  	if (debug == 0)
  		daemon(0, 0);
  	event_init();
  
  	if ((pw = getpwnam(RADIUSD_USER)) == NULL)
  		errx(EXIT_FAILURE, "user `%s' is not found in password "
  		    "database", RADIUSD_USER);
  
  	if (chroot(pw->pw_dir) == -1)
  		err(EXIT_FAILURE, "chroot");
  	if (chdir("/") == -1)
  		err(EXIT_FAILURE, "chdir(\"/\")");
  
  	if (setgroups(1, &pw->pw_gid) ||
  	    setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
  	    setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
  		err(EXIT_FAILURE, "cannot drop privileges");
  
  	signal(SIGPIPE, SIG_IGN);
  	openlog(NULL, LOG_PID, LOG_DAEMON);
  
  	signal_set(&radiusd->ev_sigterm, SIGTERM, radiusd_on_sigterm, radiusd);
  	signal_set(&radiusd->ev_sigint,  SIGINT,  radiusd_on_sigint,  radiusd);
  	signal_set(&radiusd->ev_sighup,  SIGHUP,  radiusd_on_sighup,  radiusd);
  	signal_set(&radiusd->ev_sigchld, SIGCHLD, radiusd_on_sigchld, radiusd);
  
  	if (radiusd_start(radiusd) != 0)
  		errx(EXIT_FAILURE, "start failed");
  
  	if (pledge("stdio inet", NULL) == -1)
  		err(EXIT_FAILURE, "pledge");
  
  	if (event_loop(0) < 0)
  		radiusd_stop(radiusd);
  
  	radiusd_free(radiusd);
  	event_base_free(NULL);
  
  	exit(EXIT_SUCCESS);
  }
  
  static int
  radiusd_start(struct radiusd *radiusd)
  {
  	struct radiusd_listen	*l;
  	struct radiusd_module	*module;
  	int			 s;
  	char			 hbuf[NI_MAXHOST];
  
  	TAILQ_FOREACH(l, &radiusd->listen, next) {
  		if (getnameinfo(
  		    (struct sockaddr *)&l->addr, l->addr.ipv4.sin_len,
  		    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0) {
  			log_warn("%s: getnameinfo()", __func__);
  			goto on_error;
  		}
  		if ((s = socket(l->addr.ipv4.sin_family,
  		    l->stype | SOCK_NONBLOCK, l->sproto)) == -1) {
  			log_warn("Listen %s port %d is failed: socket()",
  			    hbuf, (int)htons(l->addr.ipv4.sin_port));
  			goto on_error;
  		}
  		if (bind(s, (struct sockaddr *)&l->addr, l->addr.ipv4.sin_len)
  		    != 0) {
  			log_warn("Listen %s port %d is failed: bind()",
  			    hbuf, (int)htons(l->addr.ipv4.sin_port));
  			close(s);
  			goto on_error;
  		}
  		if (l->addr.ipv4.sin_family == AF_INET)
  			log_info("Start listening on %s:%d/udp", hbuf,
  			    (int)ntohs(l->addr.ipv4.sin_port));
  		else
  			log_info("Start listening on [%s]:%d/udp", hbuf,
  			    (int)ntohs(l->addr.ipv4.sin_port));
  		event_set(&l->ev, s, EV_READ | EV_PERSIST,
  		    radiusd_listen_on_event, l);
  		if (event_add(&l->ev, NULL) != 0) {
  			log_warn("event_add() failed at %s()", __func__);
  			close(s);
  			goto on_error;
  		}
  		l->sock = s;
  		l->radiusd = radiusd;
  	}
  
  	signal_add(&radiusd->ev_sigterm, NULL);
  	signal_add(&radiusd->ev_sigint, NULL);
  	signal_add(&radiusd->ev_sighup, NULL);
  	signal_add(&radiusd->ev_sigchld, NULL);
  
  	TAILQ_FOREACH(module, &radiusd->module, next) {
  		if (debug > 0)
  			radiusd_module_set(module, "_debug", 0, NULL);
  		radiusd_module_start(module);
  	}
  
  	return (0);
  on_error:
  	radiusd_stop(radiusd);
  
  	return (-1);
  }
  
  static void
  radiusd_stop(struct radiusd *radiusd)
  {
  	char			 hbuf[NI_MAXHOST];
  	struct radiusd_listen	*l;
  	struct radiusd_module	*module;
  
  	TAILQ_FOREACH_REVERSE(l, &radiusd->listen, radiusd_listen_head, next) {
  		if (l->sock >= 0) {
  			if (getnameinfo(
  			    (struct sockaddr *)&l->addr, l->addr.ipv4.sin_len,
  			    hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0)
  				strlcpy(hbuf, "error", sizeof(hbuf));
  			if (l->addr.ipv4.sin_family == AF_INET)
  				log_info("Stop listening on %s:%d/udp", hbuf,
  				    (int)ntohs(l->addr.ipv4.sin_port));
  			else
  				log_info("Stop listening on [%s]:%d/udp", hbuf,
  				    (int)ntohs(l->addr.ipv4.sin_port));
  			event_del(&l->ev);
  			close(l->sock);
  		}
  		l->sock = -1;
  	}
  	TAILQ_FOREACH(module, &radiusd->module, next) {
  		radiusd_module_stop(module);
  		radiusd_module_close(module);
  	}
  	if (signal_pending(&radiusd->ev_sigterm, NULL))
  		signal_del(&radiusd->ev_sigterm);
  	if (signal_pending(&radiusd->ev_sigint, NULL))
  		signal_del(&radiusd->ev_sigint);
  	if (signal_pending(&radiusd->ev_sighup, NULL))
  		signal_del(&radiusd->ev_sighup);
  	if (signal_pending(&radiusd->ev_sigchld, NULL))
  		signal_del(&radiusd->ev_sigchld);
  }
  
  static void
  radiusd_free(struct radiusd *radiusd)
  {
  	int				 i;
  	struct radiusd_listen		*listn, *listnt;
  	struct radiusd_client		*client, *clientt;
  	struct radiusd_module		*module, *modulet;
  	struct radiusd_module_ref	*modref, *modreft;
  	struct radiusd_authentication	*authen, *authent;
  
  	TAILQ_FOREACH_SAFE(authen, &radiusd->authen, next, authent) {
  		TAILQ_REMOVE(&radiusd->authen, authen, next);
  		free(authen->auth);
  		TAILQ_FOREACH_SAFE(modref, &authen->deco, next, modreft) {
  			TAILQ_REMOVE(&authen->deco, modref, next);
  			free(modref);
  		}
  		for (i = 0; authen->username[i] != NULL; i++)
  			free(authen->username[i]);
  		free(authen->username);
  		free(authen);
  	}
  	TAILQ_FOREACH_SAFE(module, &radiusd->module, next, modulet) {
  		TAILQ_REMOVE(&radiusd->module, module, next);
  		radiusd_module_unload(module);
  	}
  	TAILQ_FOREACH_SAFE(client, &radiusd->client, next, clientt) {
  		TAILQ_REMOVE(&radiusd->client, client, next);
  		explicit_bzero(client->secret, sizeof(client->secret));
  		free(client);
  	}
  	TAILQ_FOREACH_SAFE(listn, &radiusd->listen, next, listnt) {
  		TAILQ_REMOVE(&radiusd->listen, listn, next);
  		free(listn);
  	}
  	free(radiusd);
  }
  
  /***********************************************************************
   * Network event handlers
   ***********************************************************************/
  #define IPv4_cmp(_in, _addr, _mask) (				\
  	((_in)->s_addr & (_mask)->addr.ipv4.s_addr) ==		\
  	    (_addr)->addr.ipv4.s_addr)
  #define	s6_addr32(_in6)	((uint32_t *)(_in6)->s6_addr)
  #define IPv6_cmp(_in6, _addr, _mask) (				\
  	((s6_addr32(_in6)[3] & (_mask)->addr.addr32[3])		\
  	    == (_addr)->addr.addr32[3]) &&			\
  	((s6_addr32(_in6)[2] & (_mask)->addr.addr32[2])		\
  	    == (_addr)->addr.addr32[2]) &&			\
  	((s6_addr32(_in6)[1] & (_mask)->addr.addr32[1])		\
  	    == (_addr)->addr.addr32[1]) &&			\
  	((s6_addr32(_in6)[0] & (_mask)->addr.addr32[0])		\
  	    == (_addr)->addr.addr32[0]))
  
  static void
  radiusd_listen_on_event(int fd, short evmask, void *ctx)
  {
  	int				 i, sz, req_id, req_code;
  	struct radiusd_listen		*listn = ctx;
  	static u_char			 buf[65535];
  	static char			 username[256];
  	struct sockaddr_storage		 peer;
  	socklen_t			 peersz;
  	RADIUS_PACKET			*packet = NULL;
  	char				 peerstr[NI_MAXHOST + NI_MAXSERV + 30];
  	struct radiusd_authentication	*authen;
  	struct radiusd_client		*client;
  	struct radius_query		*q;
  #define in(_x)	(((struct sockaddr_in  *)_x)->sin_addr)
  #define in6(_x)	(((struct sockaddr_in6 *)_x)->sin6_addr)
  
  	if (evmask & EV_READ) {
  		peersz = sizeof(peer);
  		if ((sz = recvfrom(listn->sock, buf, sizeof(buf), 0,
  		    (struct sockaddr *)&peer, &peersz)) == -1) {
  			if (errno == EAGAIN)
  				return;
  			log_warn("%s: recvfrom() failed", __func__);
  			goto on_error;
  		}
  		RADIUSD_ASSERT(peer.ss_family == AF_INET ||
  		    peer.ss_family == AF_INET6);
  
  		/* prepare some information about this messages */
  		if (addrport_tostring((struct sockaddr *)&peer, peersz,
  		    peerstr, sizeof(peerstr)) == NULL) {
  			log_warn("%s: getnameinfo() failed", __func__);
  			goto on_error;
  		}
  		if ((packet = radius_convert_packet(buf, sz)) == NULL) {
  			log_warn("%s: radius_convert_packet() failed",
  			    __func__);
  			goto on_error;
  		}
  		req_id = radius_get_id(packet);
  		req_code = radius_get_code(packet);
  
  		/*
  		 * Find a matching `client' entry
  		 */
  		TAILQ_FOREACH(client, &listn->radiusd->client, next) {
  			if (client->af != peer.ss_family)
  				continue;
  			if (peer.ss_family == AF_INET &&
  			    IPv4_cmp(&((struct sockaddr_in *)&peer)->sin_addr,
  			    &client->addr, &client->mask))
  				break;
  			else if (peer.ss_family == AF_INET6 &&
  			    IPv6_cmp(&((struct sockaddr_in6 *)&peer)->sin6_addr,
  			    &client->addr, &client->mask))
  				break;
  		}
  		if (client == NULL) {
  			log_warnx("Received %s(code=%d) from %s id=%d: "
  			    "no `client' matches", radius_code_string(req_code),
  			    req_code, peerstr, req_id);
  			goto on_error;
  		}
  
  		/* Check the client's Message-Authenticator */
  		if (client->msgauth_required &&
  		    !radius_has_attr(packet,
  		    RADIUS_TYPE_MESSAGE_AUTHENTICATOR)) {
  			log_warnx("Received %s(code=%d) from %s id=%d: "
  			    "no message authenticator",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id);
  			goto on_error;
  		}
  
  		if (radius_has_attr(packet,
  		    RADIUS_TYPE_MESSAGE_AUTHENTICATOR) &&
  		    radius_check_message_authenticator(packet, client->secret)
  		    != 0) {
  			log_warnx("Received %s(code=%d) from %s id=%d: "
  			    "bad message authenticator",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id);
  			goto on_error;
  		}
  
  		/*
  		 * Find a duplicate request.  In RFC 2865, it has the same
  		 * source IP address and source UDP port and Identifier.
  		 */
  		TAILQ_FOREACH(q, &listn->radiusd->query, next) {
  			if (peer.ss_family == q->clientaddr.ss_family &&
  			    ((peer.ss_family == AF_INET &&
  			    in(&q->clientaddr).s_addr ==
  			    in(&peer).s_addr) ||
  			    (peer.ss_family == AF_INET6 &&
  			    IN6_ARE_ADDR_EQUAL(
  			    &in6(&q->clientaddr), &in6(&peer)))) &&
  			    ((struct sockaddr_in *)&q->clientaddr)->sin_port ==
  			    ((struct sockaddr_in *)&peer)->sin_port &&
  			    req_id == q->req_id)
  				break;	/* found it */
  		}
  		if (q != NULL) {
  			log_info("Received %s(code=%d) from %s id=%d: "
  			    "duplicate request by q=%u",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id, q->id);
  			/* XXX RFC 5080 suggests to answer the cached result */
  			goto on_error;
  		}
  
  		/* FIXME: we can support other request codes */
  		if (req_code != RADIUS_CODE_ACCESS_REQUEST) {
  			log_info("Received %s(code=%d) from %s id=%d: %s "
  			    "is not supported in this implementation",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id, radius_code_string(req_code));
  			goto on_error;
  		}
  
  		/*
  		 * Find a matching `authenticate' entry
  		 */
  		if (radius_get_string_attr(packet, RADIUS_TYPE_USER_NAME,
  		    username, sizeof(username)) != 0) {
  			log_info("Received %s(code=%d) from %s id=%d: "
  			    "no User-Name attribute",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id);
  			goto on_error;
  		}
  		TAILQ_FOREACH(authen, &listn->radiusd->authen, next) {
  			for (i = 0; authen->username[i] != NULL; i++) {
  				if (fnmatch(authen->username[i], username, 0)
  				    == 0)
  					goto found;
  			}
  		}
  		if (authen == NULL) {
  			log_warnx("Received %s(code=%d) from %s id=%d "
  			    "username=%s: no `authenticate' matches.",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id, username);
  			goto on_error;
  		}
  found:
  		if (!MODULE_DO_USERPASS(authen->auth->module) &&
  		    !MODULE_DO_ACCSREQ(authen->auth->module)) {
  			log_warnx("Received %s(code=%d) from %s id=%d "
  			    "username=%s: module `%s' is not running.",
  			    radius_code_string(req_code), req_code, peerstr,
  			    req_id, username, authen->auth->module->name);
  			goto on_error;
  		}
  		if ((q = calloc(1, sizeof(struct radius_query))) == NULL) {
  			log_warn("%s: Out of memory", __func__);
  			goto on_error;
  		}
  		memcpy(&q->clientaddr, &peer, peersz);
  		strlcpy(q->username, username, sizeof(q->username));
  		q->id = ++radius_query_id_seq;
  		q->clientaddrlen = peersz;
  		q->authen = authen;
  		q->listen = listn;
  		q->req = packet;
  		q->client = client;
  		q->req_id = req_id;
  		radius_get_authenticator(packet, q->req_auth);
  
  		if (radius_query_request_decoration(q) != 0) {
  			log_warnx(
  			    "Received %s(code=%d) from %s id=%d username=%s "
  			    "q=%u: failed to decorate the request",
  			    radius_code_string(req_code), req_code, peerstr,
  			    q->req_id, q->username, q->id);
  			radiusd_access_request_aborted(q);
  			return;
  		}
  		log_info("Received %s(code=%d) from %s id=%d username=%s "
  		    "q=%u: `%s' authentication is starting",
  		    radius_code_string(req_code), req_code, peerstr, q->req_id,
  		    q->username, q->id, q->authen->auth->module->name);
  		TAILQ_INSERT_TAIL(&listn->radiusd->query, q, next);
  
  		if (MODULE_DO_ACCSREQ(authen->auth->module)) {
  			radiusd_module_access_request(authen->auth->module, q);
  		} else if (MODULE_DO_USERPASS(authen->auth->module))
  			radiusd_module_userpass(authen->auth->module, q);
  
  		return;
  	}
  on_error:
  	if (packet != NULL)
  		radius_delete_packet(packet);
  #undef in
  #undef in6
  
  	return;
  }
  
  static int
  radius_query_request_decoration(struct radius_query *q)
  {
  	struct radiusd_module_ref	*deco;
  
  	TAILQ_FOREACH(deco, &q->authen->deco, next) {
  		/* XXX decoration doesn't work for this moment.  */
  		if (deco->module->request_decoration != NULL &&
  		    deco->module->request_decoration(NULL, q) != 0) {
  			log_warnx("q=%u request decoration `%s' failed", q->id,
  			    deco->module->name);
  			return (-1);
  		}
  	}
  
  	return (0);
  }
  
  static int
  radius_query_response_decoration(struct radius_query *q)
  {
  	struct radiusd_module_ref	*deco;
  
  	TAILQ_FOREACH(deco, &q->authen->deco, next) {
  		/* XXX decoration doesn't work for this moment.  */
  		if (deco->module->response_decoration != NULL &&
  		    deco->module->response_decoration(NULL, q) != 0) {
  			log_warnx("q=%u response decoration `%s' failed", q->id,
  			    deco->module->name);
  			return (-1);
  		}
  	}
  
  	return (0);
  }
  
  /***********************************************************************
   * Callback functions from the modules
   ***********************************************************************/
  void
  radiusd_access_request_answer(struct radius_query *q)
  {
  	int		 sz, res_id, res_code;
  	char		 buf[NI_MAXHOST + NI_MAXSERV + 30];
  	const char	*authen_secret = q->authen->auth->module->secret;
  
  	radius_set_request_packet(q->res, q->req);
  
  	if (authen_secret == NULL) {
  		/*
  		 * The module couldn't check the autheticators
  		 */
  		if (radius_check_response_authenticator(q->res,
  		    q->client->secret) != 0) {
  			log_info("Response from module has bad response "
  			    "authenticator: id=%d", q->id);
  			goto on_error;
  		}
  		if (radius_has_attr(q->res,
  		    RADIUS_TYPE_MESSAGE_AUTHENTICATOR) &&
  		    radius_check_message_authenticator(q->res,
  		    q->client->secret) != 0) {
  			log_info("Response from module has bad message "
  			    "authenticator: id=%d", q->id);
  			goto on_error;
  		}
  	}
  
  	/* Decorate the response */
  	if (radius_query_response_decoration(q) != 0)
  		goto on_error;
  
  	if (radiusd_access_response_fixup(q) != 0)
  		goto on_error;
  
  	res_id = radius_get_id(q->res);
  	res_code = radius_get_code(q->res);
  
  	/* Reset response/message authenticator */
  	if (radius_has_attr(q->res, RADIUS_TYPE_MESSAGE_AUTHENTICATOR))
  		radius_del_attr_all(q->res, RADIUS_TYPE_MESSAGE_AUTHENTICATOR);
  	radius_put_message_authenticator(q->res, q->client->secret);
  	radius_set_response_authenticator(q->res, q->client->secret);
  
  	log_info("Sending %s(code=%d) to %s id=%u q=%u",
  	    radius_code_string(res_code), res_code,
  	    addrport_tostring((struct sockaddr *)&q->clientaddr,
  		    q->clientaddrlen, buf, sizeof(buf)), res_id, q->id);
  
  	if ((sz = sendto(q->listen->sock, radius_get_data(q->res),
  	    radius_get_length(q->res), 0,
  	    (struct sockaddr *)&q->clientaddr, q->clientaddrlen)) <= 0)
  		log_warn("Sending a RADIUS response failed");
  on_error:
  	radiusd_access_request_aborted(q);
  }
  
  void
  radiusd_access_request_aborted(struct radius_query *q)
  {
  	if (q->req != NULL)
  		radius_delete_packet(q->req);
  	if (q->res != NULL)
  		radius_delete_packet(q->res);
  	TAILQ_REMOVE(&q->listen->radiusd->query, q, next);
  	free(q);
  }
  
  /***********************************************************************
   * Signal handlers
   ***********************************************************************/
  static void
  radiusd_on_sigterm(int fd, short evmask, void *ctx)
  {
  	struct radiusd	*radiusd = ctx;
  
  	log_info("Received SIGTERM");
  	radiusd_stop(radiusd);
  }
  
  static void
  radiusd_on_sigint(int fd, short evmask, void *ctx)
  {
  	struct radiusd	*radiusd = ctx;
  
  	log_info("Received SIGINT");
  	radiusd_stop(radiusd);
  }
  
  static void
  radiusd_on_sighup(int fd, short evmask, void *ctx)
  {
  	log_info("Received SIGHUP");
  }
  
  static void
  radiusd_on_sigchld(int fd, short evmask, void *ctx)
  {
  	struct radiusd		*radiusd = ctx;
  	struct radiusd_module	*module;
  	pid_t			 pid;
  	int			 status;
  
  	log_debug("Received SIGCHLD");
  	while ((pid = wait3(&status, WNOHANG, NULL)) != 0) {
  		if (pid == -1)
  			break;
  		TAILQ_FOREACH(module, &radiusd->module, next) {
  			if (module->pid == pid) {
  				if (WIFEXITED(status))
  					log_warnx("module `%s'(pid=%d) exited "
  					    "with status %d", module->name,
  					    (int)pid, WEXITSTATUS(status));
  				else
  					log_warnx("module `%s'(pid=%d) exited "
  					    "by signal %d", module->name,
  					    (int)pid, WTERMSIG(status));
  				break;
  			}
  		}
  		if (!module) {
  			if (WIFEXITED(status))
  				log_warnx("unkown child process pid=%d exited "
  				    "with status %d", (int)pid,
  				     WEXITSTATUS(status));
  			else
  				log_warnx("unkown child process pid=%d exited "
  				    "by signal %d", (int)pid,
  				    WTERMSIG(status));
  		}
  	}
  }
  
  static const char *
  radius_code_string(int code)
  {
  	int			i;
  	struct _codestrings {
  		int		 code;
  		const char	*string;
  	} codestrings[] = {
  	    { RADIUS_CODE_ACCESS_REQUEST,	"Access-Request" },
  	    { RADIUS_CODE_ACCESS_ACCEPT,	"Access-Accept" },
  	    { RADIUS_CODE_ACCESS_REJECT,	"Access-Reject" },
  	    { RADIUS_CODE_ACCOUNTING_REQUEST,	"Accounting-Request" },
  	    { RADIUS_CODE_ACCOUNTING_RESPONSE,	"Accounting-Response" },
  	    { RADIUS_CODE_ACCESS_CHALLENGE,	"Access-Challenge" },
  	    { RADIUS_CODE_STATUS_SERVER,	"Status-Server" },
  	    { RADIUS_CODE_STATUS_CLIENT,	"Status-Client" },
  	    { -1,				NULL }
  	};
  
  	for (i = 0; codestrings[i].code != -1; i++)
  		if (codestrings[i].code == code)
  			return (codestrings[i].string);
  
  	return ("Unknown");
  }
  
  void
  radiusd_conf_init(struct radiusd *conf)
  {
  
  	TAILQ_INIT(&conf->listen);
  	TAILQ_INIT(&conf->module);
  	TAILQ_INIT(&conf->authen);
  	TAILQ_INIT(&conf->client);
  
  	/*
  	 * TODO: load the standard modules
  	 */
  #if 0
  static struct radiusd_module *radiusd_standard_modules[] = {
  	NULL
  };
  
  	u_int			 i;
  	struct radiusd_module	*module;
  	for (i = 0; radiusd_standard_modules[i] != NULL; i++) {
  		module = radiusd_create_module_class(
  		    radiusd_standard_modules[i]);
  		TAILQ_INSERT_TAIL(&conf->module, module, next);
  	}
  #endif
  
  	return;
  }
  
  /*
   * Fix some attributes which depend the secret value.
   */
  static int
  radiusd_access_response_fixup(struct radius_query *q)
  {
  	int		 res_id;
  	size_t		 attrlen;
  	u_char		 req_auth[16], attrbuf[256];
  	const char	*authen_secret = q->authen->auth->module->secret;
  
  	radius_get_authenticator(q->req, req_auth);
  
  	if ((authen_secret != NULL &&
  	    strcmp(authen_secret, q->client->secret) != 0) ||
  	    timingsafe_bcmp(q->req_auth, req_auth, 16) != 0) {
  		const char *olds = q->client->secret;
  		const char *news = authen_secret;
  
  		/* RFC 2865 Tunnel-Password */
  		attrlen = sizeof(attrlen);
  		if (radius_get_raw_attr(q->res, RADIUS_TYPE_TUNNEL_PASSWORD,
  		    attrbuf, &attrlen) == 0) {
  			radius_attr_unhide(news, req_auth,
  			    attrbuf, attrbuf + 3, attrlen - 3);
  			radius_attr_hide(olds, q->req_auth,
  			    attrbuf, attrbuf + 3, attrlen - 3);
  
  			radius_del_attr_all(q->res,
  			    RADIUS_TYPE_TUNNEL_PASSWORD);
  			radius_put_raw_attr(q->res,
  			    RADIUS_TYPE_TUNNEL_PASSWORD, attrbuf, attrlen);
  		}
  
  		/* RFC 2548 Microsoft MPPE-{Send,Recv}-Key */
  		attrlen = sizeof(attrlen);
  		if (radius_get_vs_raw_attr(q->res, RADIUS_VENDOR_MICROSOFT,
  		    RADIUS_VTYPE_MPPE_SEND_KEY, attrbuf, &attrlen) == 0) {
  
  			/* Re-crypt the KEY */
  			radius_attr_unhide(news, req_auth,
  			    attrbuf, attrbuf + 2, attrlen - 2);
  			radius_attr_hide(olds, q->req_auth,
  			    attrbuf, attrbuf + 2, attrlen - 2);
  
  			radius_del_vs_attr_all(q->res, RADIUS_VENDOR_MICROSOFT,
  			    RADIUS_VTYPE_MPPE_SEND_KEY);
  			radius_put_vs_raw_attr(q->res, RADIUS_VENDOR_MICROSOFT,
  			    RADIUS_VTYPE_MPPE_SEND_KEY, attrbuf, attrlen);
  		}
  		attrlen = sizeof(attrlen);
  		if (radius_get_vs_raw_attr(q->res, RADIUS_VENDOR_MICROSOFT,
  		    RADIUS_VTYPE_MPPE_RECV_KEY, attrbuf, &attrlen) == 0) {
  
  			/* Re-crypt the KEY */
  			radius_attr_unhide(news, req_auth,
  			    attrbuf, attrbuf + 2, attrlen - 2);
  			radius_attr_hide(olds, q->req_auth,
  			    attrbuf, attrbuf + 2, attrlen - 2);
  
  			radius_del_vs_attr_all(q->res, RADIUS_VENDOR_MICROSOFT,
  			    RADIUS_VTYPE_MPPE_RECV_KEY);
  			radius_put_vs_raw_attr(q->res, RADIUS_VENDOR_MICROSOFT,
  			    RADIUS_VTYPE_MPPE_RECV_KEY, attrbuf, attrlen);
  		}
  	}
  
  	res_id = radius_get_id(q->res);
  	if (res_id != q->req_id) {
  		/* authentication server change the id */
  		radius_set_id(q->res, q->req_id);
  	}
  
  	return (0);
  }
  
  void
  radius_attr_hide(const char *secret, const char *authenticator,
      const u_char *salt, u_char *plain, int plainlen)
  {
  	int	  i, j;
  	u_char	  b[16];
  	MD5_CTX	  md5ctx;
  
  	i = 0;
  	do {
  		MD5Init(&md5ctx);
  		MD5Update(&md5ctx, secret, strlen(secret));
  		if (i == 0) {
  			MD5Update(&md5ctx, authenticator, 16);
  			if (salt != NULL)
  				MD5Update(&md5ctx, salt, 2);
  		} else
  			MD5Update(&md5ctx, plain + i - 16, 16);
  		MD5Final(b, &md5ctx);
  
  		for (j = 0; j < 16 && i < plainlen; i++, j++)
  			plain[i] ^= b[j];
  	} while (i < plainlen);
  }
  
  void
  radius_attr_unhide(const char *secret, const char *authenticator,
      const u_char *salt, u_char *crypt0, int crypt0len)
  {
  	int	  i, j;
  	u_char	  b[16];
  	MD5_CTX	  md5ctx;
  
  	i = 16 * ((crypt0len - 1) / 16);
  	while (i >= 0) {
  		MD5Init(&md5ctx);
  		MD5Update(&md5ctx, secret, strlen(secret));
  		if (i == 0) {
  			MD5Update(&md5ctx, authenticator, 16);
  			if (salt != NULL)
  				MD5Update(&md5ctx, salt, 2);
  		} else
  			MD5Update(&md5ctx, crypt0 + i - 16, 16);
  		MD5Final(b, &md5ctx);
  
  		for (j = 0; j < 16 && i + j < crypt0len; j++)
  			crypt0[i + j] ^= b[j];
  		i -= 16;
  	}
  }
  
  static struct radius_query *
  radiusd_find_query(struct radiusd *radiusd, u_int q_id)
  {
  	struct radius_query	*q;
  
  	TAILQ_FOREACH(q, &radiusd->query, next) {
  		if (q->id == q_id)
  			return (q);
  	}
  	return (NULL);
  }
  
  /***********************************************************************
   * radiusd module handling
   ***********************************************************************/
  struct radiusd_module *
  radiusd_module_load(struct radiusd *radiusd, const char *path, const char *name)
  {
  	struct radiusd_module		*module = NULL;
  	pid_t				 pid;
  	int				 ival, pairsock[] = { -1, -1 };
  	const char			*av[3];
  	ssize_t				 n;
  	struct imsg			 imsg;
  
  	module = calloc(1, sizeof(struct radiusd_module));
  	if (module == NULL)
  		fatal("Out of memory");
  	module->radiusd = radiusd;
  
  	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pairsock) == -1) {
  		log_warn("Could not load module `%s'(%s): pipe()", name, path);
  		goto on_error;
  	}
  
  	pid = fork();
  	if (pid == -1) {
  		log_warn("Could not load module `%s'(%s): fork()", name, path);
  		goto on_error;
  	}
  	if (pid == 0) {
  		setsid();
  		close(pairsock[0]);
  		av[0] = path;
  		av[1] = name;
  		av[2] = NULL;
  		dup2(pairsock[1], STDIN_FILENO);
  		dup2(pairsock[1], STDOUT_FILENO);
  		close(pairsock[1]);
  		closefrom(STDERR_FILENO + 1);
  		execv(path, (char * const *)av);
  		log_warn("Failed to execute %s", path);
  		_exit(EXIT_FAILURE);
  	}
  	close(pairsock[1]);
  
  	module->fd = pairsock[0];
  	if ((ival = fcntl(module->fd, F_GETFL)) == -1) {
  		log_warn("Could not load module `%s': fcntl(F_GETFL)",
  		    name);
  		goto on_error;
  	}
  	if (fcntl(module->fd, F_SETFL, ival | O_NONBLOCK) == -1) {
  		log_warn("Could not load module `%s': fcntl(F_SETFL,O_NONBLOCK)",
  		    name);
  		goto on_error;
  	}
  	strlcpy(module->name, name, sizeof(module->name));
  	module->pid = pid;
  	imsg_init(&module->ibuf, module->fd);
  
  	if (imsg_sync_read(&module->ibuf, MODULE_IO_TIMEOUT) <= 0 ||
  	    (n = imsg_get(&module->ibuf, &imsg)) <= 0) {
  		log_warnx("Could not load module `%s': module didn't "
  		    "respond", name);
  		goto on_error;
  	}
  	if (imsg.hdr.type != IMSG_RADIUSD_MODULE_LOAD) {
  		imsg_free(&imsg);
  		log_warnx("Could not load module `%s': unknown imsg type=%d",
  		    name, imsg.hdr.type);
  		goto on_error;
  	}
  
  	module->capabilities =
  	    ((struct radiusd_module_load_arg *)imsg.data)->cap;
  
  	log_debug("Loaded module `%s' successfully.  pid=%d", module->name,
  	    module->pid);
  	imsg_free(&imsg);
  
  	return (module);
  
  on_error:
  	free(module);
  	if (pairsock[0] >= 0)
  		close(pairsock[0]);
  	if (pairsock[1] >= 0)
  		close(pairsock[1]);
  
  	return (NULL);
  }
  
  void
  radiusd_module_start(struct radiusd_module *module)
  {
  	int		 datalen;
  	struct imsg	 imsg;
  	struct timeval	 tv = { 0, 0 };
  
  	RADIUSD_ASSERT(module->fd >= 0);
  	imsg_compose(&module->ibuf, IMSG_RADIUSD_MODULE_START, 0, 0, -1,
  	    NULL, 0);
  	imsg_sync_flush(&module->ibuf, MODULE_IO_TIMEOUT);
  	if (imsg_sync_read(&module->ibuf, MODULE_IO_TIMEOUT) <= 0 ||
  	    imsg_get(&module->ibuf, &imsg) <= 0) {
  		log_warnx("Module `%s' could not start: no response",
  		    module->name);
  		goto on_fail;
  	}
  
  	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
  	if (imsg.hdr.type != IMSG_OK) {
  		if (imsg.hdr.type == IMSG_NG) {
  			if (datalen > 0)
  				log_warnx("Module `%s' could not start: %s",
  				    module->name, (char *)imsg.data);
  			else
  				log_warnx("Module `%s' could not start",
  				    module->name);
  		} else
  			log_warnx("Module `%s' could not started: module "
  			    "returned unknow message type %d", module->name,
  			    imsg.hdr.type);
  		goto on_fail;
  	}
  
  	event_set(&module->ev, module->fd, EV_READ, radiusd_module_on_imsg_io,
  	    module);
  	event_add(&module->ev, &tv);
  	log_debug("Module `%s' started successfully", module->name);
  
  	return;
  on_fail:
  	radiusd_module_close(module);
  	return;
  }
  
  void
  radiusd_module_stop(struct radiusd_module *module)
  {
  	module->stopped = true;
  
  	if (module->secret != NULL) {
  		freezero(module->secret, strlen(module->secret));
  		module->secret = NULL;
  	}
  
  	if (module->fd >= 0) {
  		imsg_compose(&module->ibuf, IMSG_RADIUSD_MODULE_STOP, 0, 0, -1,
  		    NULL, 0);
  		radiusd_module_reset_ev_handler(module);
  	}
  }
  
  static void
  radiusd_module_close(struct radiusd_module *module)
  {
  	if (module->fd >= 0) {
  		event_del(&module->ev);
  		imsg_clear(&module->ibuf);
  		close(module->fd);
  		module->fd = -1;
  	}
  }
  
  void
  radiusd_module_unload(struct radiusd_module *module)
  {
  	free(module->radpkt);
  	radiusd_module_close(module);
  	free(module);
  }
  
  static void
  radiusd_module_on_imsg_io(int fd, short evmask, void *ctx)
  {
  	struct radiusd_module	*module = ctx;
  	int			 ret;
  
  	if (evmask & EV_WRITE)
  		module->writeready = true;
  
  	if (evmask & EV_READ || module->ibuf.r.wpos > IMSG_HEADER_SIZE) {
  		if (radiusd_module_imsg_read(module,
  		    (evmask & EV_READ)? true : false) == -1)
  			goto on_error;
  	}
  
  	while (module->writeready && module->ibuf.w.queued) {
  		ret = msgbuf_write(&module->ibuf.w);
  		if (ret > 0)
  			continue;
  		module->writeready = false;
  		if (ret == 0 && errno == EAGAIN)
  			break;
  		log_warn("Failed to write to module `%s': msgbuf_write()",
  		    module->name);
  		goto on_error;
  	}
  	radiusd_module_reset_ev_handler(module);
  
  	return;
  on_error:
  	radiusd_module_close(module);
  }
  
  static void
  radiusd_module_reset_ev_handler(struct radiusd_module *module)
  {
  	short		 evmask;
  	struct timeval	*tvp = NULL, tv = { 0, 0 };
  
  	RADIUSD_ASSERT(module->fd >= 0);
  	event_del(&module->ev);
  
  	evmask = EV_READ;
  	if (module->ibuf.w.queued) {
  		if (!module->writeready)
  			evmask |= EV_WRITE;
  		else
  			tvp = &tv;	/* fire immediately */
  	} else if (module->ibuf.r.wpos > IMSG_HEADER_SIZE)
  		tvp = &tv;		/* fire immediately */
  
  	/* module stopped and no event handler is set */
  	if (evmask & EV_WRITE && tvp == NULL && module->stopped) {
  		/* stop requested and no more to write */
  		radiusd_module_close(module);
  		return;
  	}
  
  	event_set(&module->ev, module->fd, evmask, radiusd_module_on_imsg_io,
  	    module);
  	if (event_add(&module->ev, tvp) == -1) {
  		log_warn("Could not set event handlers for module `%s': "
  		    "event_add()", module->name);
  		radiusd_module_close(module);
  	}
  }
  
  static int
  radiusd_module_imsg_read(struct radiusd_module *module, bool doread)
  {
  	int		 n;
  	struct imsg	 imsg;
  
  	if (doread) {
  		if ((n = imsg_read(&module->ibuf)) == -1 || n == 0) {
  			if (n == -1 && errno == EAGAIN)
  				return (0);
  			if (n == -1)
  				log_warn("Receiving a message from module `%s' "
  				    "failed: imsg_read", module->name);
  			/* else closed */
  			radiusd_module_close(module);
  			return (-1);
  		}
  	}
  	for (;;) {
  		if ((n = imsg_get(&module->ibuf, &imsg)) == -1) {
  			log_warn("Receiving a message from module `%s' failed: "
  			    "imsg_get", module->name);
  			return (-1);
  		}
  		if (n == 0)
  			return (0);
  		radiusd_module_imsg(module, &imsg);
  	}
  
  	return (0);
  }
  
  static void
  radiusd_module_imsg(struct radiusd_module *module, struct imsg *imsg)
  {
  	int			 datalen;
  	struct radius_query	*q;
  	u_int			 q_id;
  
  	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
  	switch (imsg->hdr.type) {
  	case IMSG_RADIUSD_MODULE_NOTIFY_SECRET:
  		if (datalen > 0) {
  			module->secret = strdup(imsg->data);
  			if (module->secret == NULL)
  				log_warn("Could not handle NOTIFY_SECRET "
  				    "from `%s'", module->name);
  		}
  		break;
  	case IMSG_RADIUSD_MODULE_USERPASS_OK:
  	case IMSG_RADIUSD_MODULE_USERPASS_FAIL:
  	    {
  		char			*msg = NULL;
  		const char		*msgtypestr;
  
  		msgtypestr = (imsg->hdr.type == IMSG_RADIUSD_MODULE_USERPASS_OK)
  		    ? "USERPASS_OK" : "USERPASS_NG";
  
  		q_id = *(u_int *)imsg->data;
  		if (datalen > (ssize_t)sizeof(u_int))
  			msg = (char *)(((u_int *)imsg->data) + 1);
  
  		q = radiusd_find_query(module->radiusd, q_id);
  		if (q == NULL) {
  			log_warnx("Received %s from `%s', but query id=%u "
  			    "unknown", msgtypestr, module->name, q_id);
  			break;
  		}
  
  		if ((q->res = radius_new_response_packet(
  		    (imsg->hdr.type == IMSG_RADIUSD_MODULE_USERPASS_OK)
  		    ? RADIUS_CODE_ACCESS_ACCEPT : RADIUS_CODE_ACCESS_REJECT,
  		    q->req)) == NULL) {
  			log_warn("radius_new_response_packet() failed");
  			radiusd_access_request_aborted(q);
  		} else {
  			if (msg)
  				radius_put_string_attr(q->res,
  				    RADIUS_TYPE_REPLY_MESSAGE, msg);
  			radius_set_response_authenticator(q->res,
  			    q->client->secret);
  			radiusd_access_request_answer(q);
  		}
  		break;
  	    }
  	case IMSG_RADIUSD_MODULE_ACCSREQ_ANSWER:
  	    {
  		static struct radiusd_module_radpkt_arg *ans;
  		if (datalen <
  		    (ssize_t)sizeof(struct radiusd_module_radpkt_arg)) {
  			log_warnx("Received ACCSREQ_ANSWER message, but "
  			    "length is wrong");
  			break;
  		}
  		q_id = ((struct radiusd_module_radpkt_arg *)imsg->data)->q_id;
  		q = radiusd_find_query(module->radiusd, q_id);
  		if (q == NULL) {
  			log_warnx("Received ACCSREQ_ANSWER from %s, but query "
  			    "id=%u unknown", module->name, q_id);
  			break;
  		}
  		if ((ans = radiusd_module_recv_radpkt(module, imsg,
  		    IMSG_RADIUSD_MODULE_ACCSREQ_ANSWER,
  		    "ACCSREQ_ANSWER")) != NULL) {
  			q->res = radius_convert_packet(
  			    module->radpkt, module->radpktoff);
  			radiusd_access_request_answer(q);
  			module->radpktoff = 0;
  		}
  		break;
  	    }
  	case IMSG_RADIUSD_MODULE_ACCSREQ_ABORTED:
  	    {
  		q_id = *((u_int *)imsg->data);
  		q = radiusd_find_query(module->radiusd, q_id);
  		if (q == NULL) {
  			log_warnx("Received ACCSREQ_ABORT from %s, but query "
  			    "id=%u unknown", module->name, q_id);
  			break;
  		}
  		radiusd_access_request_aborted(q);
  		break;
  	    }
  	default:
  		RADIUSD_DBG(("Unhandled imsg type=%d",
  		    imsg->hdr.type));
  	}
  }
  
  static struct radiusd_module_radpkt_arg *
  radiusd_module_recv_radpkt(struct radiusd_module *module, struct imsg *imsg,
      uint32_t imsg_type, const char *type_str)
  {
  	struct radiusd_module_radpkt_arg	*ans;
  	int					 datalen, chunklen;
  
  	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
  	ans = (struct radiusd_module_radpkt_arg *)imsg->data;
  	if (module->radpktsiz < ans->pktlen) {
  		u_char *nradpkt;
  		if ((nradpkt = realloc(module->radpkt, ans->pktlen)) == NULL) {
  			log_warn("Could not handle received %s message from "
  			    "`%s'", type_str, module->name);
  			goto on_fail;
  		}
  		module->radpkt = nradpkt;
  		module->radpktsiz = ans->pktlen;
  	}
  	chunklen = datalen - sizeof(struct radiusd_module_radpkt_arg);
  	if (chunklen > module->radpktsiz - module->radpktoff) {
  		log_warnx("Could not handle received %s message from `%s': "
  		    "received length is too big", type_str, module->name);
  		goto on_fail;
  	}
  	memcpy(module->radpkt + module->radpktoff,
  	    (caddr_t)(ans + 1), chunklen);
  	module->radpktoff += chunklen;
  	if (!ans->final)
  		return (NULL);	/* again */
  	if (module->radpktoff != ans->pktlen) {
  		log_warnx("Could not handle received %s message from `%s': "
  		    "length is mismatch", type_str, module->name);
  		goto on_fail;
  	}
  
  	return (ans);
  on_fail:
  	module->radpktoff = 0;
  	return (NULL);
  }
  
  int
  radiusd_module_set(struct radiusd_module *module, const char *name,
      int argc, char * const * argv)
  {
  	struct radiusd_module_set_arg	 arg;
  	struct radiusd_module_object	*val;
  	int				 i, niov = 0;
  	u_char				*buf = NULL, *buf0;
  	ssize_t				 n;
  	size_t				 bufsiz = 0, bufoff = 0, bufsiz0;
  	size_t				 vallen, valsiz;
  	struct iovec			 iov[2];
  	struct imsg			 imsg;
  
  	memset(&arg, 0, sizeof(arg));
  	arg.nparamval = argc;
  	strlcpy(arg.paramname, name, sizeof(arg.paramname));
  
  	iov[niov].iov_base = &arg;
  	iov[niov].iov_len = sizeof(struct radiusd_module_set_arg);
  	niov++;
  
  	for (i = 0; i < argc; i++) {
  		vallen = strlen(argv[i]) + 1;
  		valsiz = sizeof(struct radiusd_module_object) + vallen;
  		if (bufsiz < bufoff + valsiz) {
  			bufsiz0 = bufoff + valsiz + 128;
  			if ((buf0 = realloc(buf, bufsiz0)) == NULL) {
  				log_warn("Failed to set config parameter to "
  				    "module `%s': realloc", module->name);
  				goto on_error;
  			}
  			buf = buf0;
  			bufsiz = bufsiz0;
  			memset(buf + bufoff, 0, bufsiz - bufoff);
  		}
  		val = (struct radiusd_module_object *)(buf + bufoff);
  		val->size = valsiz;
  		memcpy(val + 1, argv[i], vallen);
  
  		bufoff += valsiz;
  	}
  	iov[niov].iov_base = buf;
  	iov[niov].iov_len = bufoff;
  	niov++;
  
  	if (imsg_composev(&module->ibuf, IMSG_RADIUSD_MODULE_SET_CONFIG, 0, 0,
  	    -1, iov, niov) == -1) {
  		log_warn("Failed to set config parameter to module `%s': "
  		    "imsg_composev", module->name);
  		goto on_error;
  	}
  	if (imsg_sync_flush(&module->ibuf, MODULE_IO_TIMEOUT) == -1) {
  		log_warn("Failed to set config parameter to module `%s': "
  		    "imsg_flush_timeout", module->name);
  		goto on_error;
  	}
  	for (;;) {
  		if (imsg_sync_read(&module->ibuf, MODULE_IO_TIMEOUT) <= 0) {
  			log_warn("Failed to get reply from module `%s': "
  			    "imsg_sync_read", module->name);
  			goto on_error;
  		}
  		if ((n = imsg_get(&module->ibuf, &imsg)) > 0)
  			break;
  		if (n < 0) {
  			log_warn("Failed to get reply from module `%s': "
  			    "imsg_get", module->name);
  			goto on_error;
  		}
  	}
  	if (imsg.hdr.type == IMSG_NG) {
  		log_warnx("Could not set `%s' for module `%s': %s", name,
  		    module->name, (char *)imsg.data);
  		goto on_error;
  	} else if (imsg.hdr.type != IMSG_OK) {
  		imsg_free(&imsg);
  		log_warnx("Failed to get reply from module `%s': "
  		    "unknown imsg type=%d", module->name, imsg.hdr.type);
  		goto on_error;
  	}
  	imsg_free(&imsg);
  
  	free(buf);
  	return (0);
  
  on_error:
  	free(buf);
  	return (-1);
  }
  
  static void
  radiusd_module_userpass(struct radiusd_module *module, struct radius_query *q)
  {
  	struct radiusd_module_userpass_arg userpass;
  
  	memset(&userpass, 0, sizeof(userpass));
  	userpass.q_id = q->id;
  
  	if (radius_get_user_password_attr(q->req, userpass.pass,
  	    sizeof(userpass.pass), q->client->secret) == 0)
  		userpass.has_pass = true;
  	else
  		userpass.has_pass = false;
  
  	if (strlcpy(userpass.user, q->username, sizeof(userpass.user))
  	    >= sizeof(userpass.user)) {
  		log_warnx("Could request USERPASS to module `%s': "
  		    "User-Name too long", module->name);
  		goto on_error;
  	}
  	imsg_compose(&module->ibuf, IMSG_RADIUSD_MODULE_USERPASS, 0, 0, -1,
  	    &userpass, sizeof(userpass));
  	radiusd_module_reset_ev_handler(module);
  	return;
  on_error:
  	radiusd_access_request_aborted(q);
  }
  
  static void
  radiusd_module_access_request(struct radiusd_module *module,
      struct radius_query *q)
  {
  	struct radiusd_module_radpkt_arg	 accsreq;
  	struct iovec				 iov[2];
  	int					 off = 0, len, siz;
  	const u_char				*pkt;
  	RADIUS_PACKET				*radpkt;
  	char					 pass[256];
  
  	if ((radpkt = radius_convert_packet(radius_get_data(q->req),
  	    radius_get_length(q->req))) == NULL) {
  		log_warn("Could not send ACCSREQ for `%s'", module->name);
  		return;
  	}
  	if (q->client->secret[0] != '\0' && module->secret != NULL &&
  	    radius_get_user_password_attr(radpkt, pass, sizeof(pass),
  		    q->client->secret) == 0) {
  		radius_del_attr_all(radpkt, RADIUS_TYPE_USER_PASSWORD);
  		(void)radius_put_raw_attr(radpkt, RADIUS_TYPE_USER_PASSWORD,
  		    pass, strlen(pass));
  	}
  
  	pkt = radius_get_data(radpkt);
  	len = radius_get_length(radpkt);
  	memset(&accsreq, 0, sizeof(accsreq));
  	accsreq.q_id = q->id;
  	accsreq.pktlen = len;
  	while (off < len) {
  		siz = MAX_IMSGSIZE - sizeof(accsreq);
  		if (len - off > siz)
  			accsreq.final = false;
  		else {
  			accsreq.final = true;
  			siz = len - off;
  		}
  		iov[0].iov_base = &accsreq;
  		iov[0].iov_len = sizeof(accsreq);
  		iov[1].iov_base = (caddr_t)pkt + off;
  		iov[1].iov_len = siz;
  		imsg_composev(&module->ibuf, IMSG_RADIUSD_MODULE_ACCSREQ, 0, 0,
  		    -1, iov, 2);
  		off += siz;
  	}
  	radiusd_module_reset_ev_handler(module);
  	radius_delete_packet(radpkt);
  
  	return;
  }