/*	$OpenBSD: ike.c,v 1.50 2006/09/18 13:45:45 hshoexer Exp $	*/
/*
 * Copyright (c) 2005 Hans-Joerg Hoexer <hshoexer@openbsd.org>
 *
 * 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/stat.h>
#include <sys/queue.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/inet.h>

#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ipsecctl.h"

static void	ike_section_general(struct ipsec_rule *, FILE *);
static void	ike_section_peer(struct ipsec_addr_wrap *,
		    struct ipsec_addr_wrap *, FILE *, struct ike_auth *);
static void	ike_section_ids(struct ipsec_addr_wrap *, struct ipsec_auth *,
		    FILE *, u_int8_t);
static int	ike_get_id_type(char *);
static void	ike_section_ipsec(struct ipsec_addr_wrap *, struct
		    ipsec_addr_wrap *, struct ipsec_addr_wrap *, FILE *);
static int	ike_section_qm(struct ipsec_addr_wrap *, struct
		    ipsec_addr_wrap *, u_int8_t, u_int8_t, struct
		    ipsec_transforms *, FILE *);
static int	ike_section_mm(struct ipsec_addr_wrap *, struct
		    ipsec_transforms *, FILE *, struct ike_auth *);
static void	ike_section_qmids(u_int8_t, struct ipsec_addr_wrap *,
		    u_int16_t, struct ipsec_addr_wrap *, u_int16_t, FILE *);
static int	ike_connect(u_int8_t, struct ipsec_addr_wrap *, struct
		    ipsec_addr_wrap *, FILE *);
static int	ike_gen_config(struct ipsec_rule *, FILE *);
static int	ike_delete_config(struct ipsec_rule *, FILE *);

int		ike_print_config(struct ipsec_rule *, int);
int		ike_ipsec_establish(int, struct ipsec_rule *);

#define	SET	"C set "
#define	ADD	"C add "
#define	DELETE	"C rms "

#define ISAKMPD_FIFO	"/var/run/isakmpd.fifo"

#define CONF_DFLT_DYNAMIC_DPD_CHECK_INTERVAL	5
#define CONF_DFLT_DYNAMIC_CHECK_INTERVAL	30

char *ike_id_types[] = { "", "", "FQDN", "USER_FQDN" };

static void
ike_section_general(struct ipsec_rule *r, FILE *fd)
{
	if (r->ikemode == IKE_DYNAMIC) {
		fprintf(fd, SET "[General]:Check-interval=%d force\n",
		    CONF_DFLT_DYNAMIC_CHECK_INTERVAL);
		fprintf(fd, SET "[General]:DPD-check-interval=%d force\n",
		    CONF_DFLT_DYNAMIC_DPD_CHECK_INTERVAL);
	}
	if (r->mmlife && r->mmlife->lifetime != -1)
		fprintf(fd, SET "[General]:Default-phase-1-lifetime=%d force\n",
		    r->mmlife->lifetime);
	if (r->qmlife && r->qmlife->lifetime != -1)
		fprintf(fd, SET "[General]:Default-phase-2-lifetime=%d force\n",
		    r->qmlife->lifetime);
}

static void
ike_section_peer(struct ipsec_addr_wrap *peer, struct ipsec_addr_wrap *local,
    FILE *fd, struct ike_auth *auth)
{
	if (peer) {
		fprintf(fd, SET "[Phase 1]:%s=peer-%s force\n", peer->name,
		    peer->name);
		fprintf(fd, SET "[peer-%s]:Phase=1 force\n", peer->name);
		fprintf(fd, SET "[peer-%s]:Address=%s force\n", peer->name,
		    peer->name);
		if (local)
			fprintf(fd, SET "[peer-%s]:Local-address=%s force\n",
			    peer->name, local->name);
		if (auth->type == IKE_AUTH_PSK)
			fprintf(fd, SET "[peer-%s]:Authentication=%s force\n",
			    peer->name, auth->string);
	} else {
		fprintf(fd, SET "[Phase 1]:Default=peer-default force\n");
		fprintf(fd, SET "[peer-default]:Phase=1 force\n");
		if (local)
			fprintf(fd, SET
			    "[peer-default]:Local-address=%s force\n",
			    local->name);
		if (auth->type == IKE_AUTH_PSK)
			fprintf(fd, SET
			    "[peer-default]:Authentication=%s force\n",
			    auth->string);
	}
}

static void
ike_section_ids(struct ipsec_addr_wrap *peer, struct ipsec_auth *auth, FILE *fd,
    u_int8_t ikemode)
{
	char myname[MAXHOSTNAMELEN];

	if (auth == NULL)
		return;

	if (ikemode == IKE_DYNAMIC && auth->srcid == NULL) {
		if (gethostname(myname, sizeof(myname)) == -1)
			err(1, "ike_section_ids: gethostname");
		if ((auth->srcid = strdup(myname)) == NULL)
			err(1, "ike_section_ids: strdup");
	}
	if (auth->srcid) {
		int idtype = ike_get_id_type(auth->srcid);

		if (peer)
			fprintf(fd, SET "[peer-%s]:ID=%s-ID force\n",
			    peer->name, auth->srcid);
		else
			fprintf(fd, SET "[peer-default]:ID=%s-ID force\n",
			    auth->srcid);

		fprintf(fd, SET "[%s-ID]:ID-type=%s force\n", auth->srcid,
		    ike_id_types[idtype]);
		fprintf(fd, SET "[%s-ID]:Name=%s force\n", auth->srcid,
		    auth->srcid);
	}
	if (auth->dstid) {
		int idtype = ike_get_id_type(auth->dstid);

		if (peer) {
			fprintf(fd, SET "[peer-%s]:Remote-ID=%s-ID force\n",
			    peer->name, peer->name);
			fprintf(fd, SET "[%s-ID]:ID-type=%s force\n",
			    peer->name, ike_id_types[idtype]);
			fprintf(fd, SET "[%s-ID]:Name=%s force\n", peer->name,
			    auth->dstid);
		} else {
			fprintf(fd, SET
			    "[peer-default]:Remote-ID=default-ID force\n");
			fprintf(fd, SET "[default-ID]:ID-type=%s force\n",
			    ike_id_types[idtype]);
			fprintf(fd, SET "[default-ID]:Name=%s force\n",
			    auth->dstid);
		}
	}
}

static int
ike_get_id_type(char *string)
{
	if (strchr(string, '@'))
		return ID_UFQDN;
	else
		return ID_FQDN;
}

static void
ike_section_ipsec(struct ipsec_addr_wrap *src, struct ipsec_addr_wrap *dst,
    struct ipsec_addr_wrap *peer, FILE *fd)
{
	fprintf(fd, SET "[IPsec-%s-%s]:Phase=2 force\n", src->name, dst->name);

	if (peer)
		fprintf(fd, SET "[IPsec-%s-%s]:ISAKMP-peer=peer-%s force\n",
		    src->name, dst->name, peer->name);
	else
		fprintf(fd, SET
		    "[IPsec-%s-%s]:ISAKMP-peer=peer-default force\n",
		    src->name, dst->name);

	fprintf(fd, SET "[IPsec-%s-%s]:Configuration=qm-%s-%s force\n",
	    src->name, dst->name, src->name, dst->name);
	fprintf(fd, SET "[IPsec-%s-%s]:Local-ID=lid-%s force\n", src->name,
	    dst->name, src->name);
	fprintf(fd, SET "[IPsec-%s-%s]:Remote-ID=rid-%s force\n", src->name,
	    dst->name, dst->name);
}

static int
ike_section_qm(struct ipsec_addr_wrap *src, struct ipsec_addr_wrap *dst,
    u_int8_t satype, u_int8_t tmode, struct ipsec_transforms *qmxfs, FILE *fd)
{
	fprintf(fd, SET "[qm-%s-%s]:EXCHANGE_TYPE=QUICK_MODE force\n",
	    src->name, dst->name);
	fprintf(fd, SET "[qm-%s-%s]:Suites=QM-", src->name, dst->name);

	switch (satype) {
	case IPSEC_ESP:
		fprintf(fd, "ESP");
		break;
	case IPSEC_AH:
		fprintf(fd, "AH");
		break;
	default:
		warnx("illegal satype %d", satype);
		return (-1);
	}
	fprintf(fd, "-");

	switch (tmode) {
	case IPSEC_TUNNEL:
		break;
	case IPSEC_TRANSPORT:
		fprintf(fd, "TRP-");
		break;
	default:
		warnx("illegal encapsulation mode %d", tmode);
		return (-1);
	}

	if (qmxfs && qmxfs->encxf) {
		if (satype == IPSEC_ESP) {
			switch (qmxfs->encxf->id) {
			case ENCXF_3DES_CBC:
				fprintf(fd, "3DES");
				break;
			case ENCXF_DES_CBC:
				fprintf(fd, "DES");
				break;
			case ENCXF_AES:
				fprintf(fd, "AES");
				break;
			case ENCXF_AESCTR:
				fprintf(fd, "AESCTR");
				break;
			case ENCXF_BLOWFISH:
				fprintf(fd, "BLF");
				break;
			case ENCXF_CAST128:
				fprintf(fd, "CAST");
				break;
			default:
				warnx("illegal transform %s",
				    qmxfs->encxf->name);
				return (-1);
			}
			fprintf(fd, "-");
		} else {
			warnx("illegal transform %s", qmxfs->encxf->name);
			return (-1);
		}
	} else if (satype == IPSEC_ESP)
		fprintf(fd, "AES-");

	if (qmxfs && qmxfs->authxf) {
		switch (qmxfs->authxf->id) {
		case AUTHXF_HMAC_MD5:
			fprintf(fd, "MD5");
			break;
		case AUTHXF_HMAC_SHA1:
			fprintf(fd, "SHA");
			break;
		case AUTHXF_HMAC_RIPEMD160:
			fprintf(fd, "RIPEMD");
			break;
		case AUTHXF_HMAC_SHA2_256:
			fprintf(fd, "SHA2-256");
			break;
		case AUTHXF_HMAC_SHA2_384:
			fprintf(fd, "SHA2-384");
			break;
		case AUTHXF_HMAC_SHA2_512:
			fprintf(fd, "SHA2-512");
			break;
		default:
			warnx("illegal transform %s", qmxfs->authxf->name);
			return (-1);
		}
	} else
		fprintf(fd, "SHA2-256");

	if (qmxfs && qmxfs->groupxf) {
		switch (qmxfs->groupxf->id) {
		case GROUPXF_NONE:
			break;
		case GROUPXF_768:
			fprintf(fd, "-PFS-GRP1");
			break;
		case GROUPXF_1024:
			fprintf(fd, "-PFS-GRP2");
			break;
		case GROUPXF_1536:
			fprintf(fd, "-PFS-GRP5");
			break;
		case GROUPXF_2048:
			fprintf(fd, "-PFS-GRP14");
			break;
		case GROUPXF_3072:
			fprintf(fd, "-PFS-GRP15");
			break;
		case GROUPXF_4096:
			fprintf(fd, "-PFS-GRP16");
			break;
		case GROUPXF_6144:
			fprintf(fd, "-PFS-GRP17");
			break;
		case GROUPXF_8192:
			fprintf(fd, "-PFS-GRP18");
			break;
		default:
			warnx("illegal group %s", qmxfs->groupxf->name);
			return (-1);
		};
	} else
		fprintf(fd, "-PFS");
	fprintf(fd, "-SUITE force\n");

	return (0);
}

static int
ike_section_mm(struct ipsec_addr_wrap *peer, struct ipsec_transforms *mmxfs,
    FILE *fd, struct ike_auth *auth)
{
	if (peer) {
		fprintf(fd, SET "[peer-%s]:Configuration=mm-%s force\n",
		    peer->name, peer->name);
		fprintf(fd, SET "[mm-%s]:EXCHANGE_TYPE=ID_PROT force\n",
		    peer->name);
		fprintf(fd, ADD "[mm-%s]:Transforms=", peer->name);
	} else {
		fprintf(fd, SET
		    "[peer-default]:Configuration=mm-default force\n");
		fprintf(fd, SET "[mm-default]:EXCHANGE_TYPE=ID_PROT force\n");
		fprintf(fd, ADD "[mm-default]:Transforms=");
	}

	if (mmxfs && mmxfs->encxf) {
		switch (mmxfs->encxf->id) {
		case ENCXF_3DES_CBC:
			fprintf(fd, "3DES");
			break;
		case ENCXF_DES_CBC:
			fprintf(fd, "DES");
			break;
		case ENCXF_AES:
			fprintf(fd, "AES");
			break;
		case ENCXF_BLOWFISH:
			fprintf(fd, "BLF");
			break;
		case ENCXF_CAST128:
			fprintf(fd, "CAST");
			break;
		default:
			warnx("illegal transform %s", mmxfs->encxf->name);
			return (-1);
		}
	} else
		fprintf(fd, "AES");
	fprintf(fd, "-");

	if (mmxfs && mmxfs->authxf) {
		switch (mmxfs->authxf->id) {
		case AUTHXF_HMAC_MD5:
			fprintf(fd, "MD5");
			break;
		case AUTHXF_HMAC_SHA1:
			fprintf(fd, "SHA");
			break;
		case AUTHXF_HMAC_SHA2_256:
			fprintf(fd, "SHA2-256");
			break;
		case AUTHXF_HMAC_SHA2_384:
			fprintf(fd, "SHA2-384");
			break;
		case AUTHXF_HMAC_SHA2_512:
			fprintf(fd, "SHA2-512");
			break;
		default:
			warnx("illegal transform %s", mmxfs->authxf->name);
			return (-1);
		}
	} else
		fprintf(fd, "SHA");

	if (mmxfs && mmxfs->groupxf) {
		switch (mmxfs->groupxf->id) {
		case GROUPXF_768:
			fprintf(fd, "-GRP1");
			break;
		case GROUPXF_1024:
			fprintf(fd, "-GRP2");
			break;
		case GROUPXF_1536:
			fprintf(fd, "-GRP5");
			break;
		case GROUPXF_2048:
			fprintf(fd, "-GRP14");
			break;
		case GROUPXF_3072:
			fprintf(fd, "-GRP15");
			break;
		case GROUPXF_4096:
			fprintf(fd, "-GRP16");
			break;
		case GROUPXF_6144:
			fprintf(fd, "-GRP17");
			break;
		case GROUPXF_8192:
			fprintf(fd, "-GRP18");
			break;
		default:
			warnx("illegal group %s", mmxfs->groupxf->name);
			return (-1);
		};
	}

	if (auth->type == IKE_AUTH_RSA)
		fprintf(fd, "-RSA_SIG");
	fprintf(fd, " force\n");

	return (0);
}

static void
ike_section_qmids(u_int8_t proto, struct ipsec_addr_wrap *src,
    u_int16_t sport, struct ipsec_addr_wrap *dst, u_int16_t dport, FILE *fd)
{
	char mask[NI_MAXHOST], *network, *p;
	struct sockaddr_storage sas;
	struct sockaddr *sa = (struct sockaddr *)&sas;

	if (src->netaddress) {
		bzero(&sas, sizeof(struct sockaddr_storage));
		bzero(mask, sizeof(mask));
		sa->sa_family = src->af;
		switch (src->af) {
		case AF_INET:
			sa->sa_len = sizeof(struct sockaddr_in);
			bcopy(&src->mask.ipa,
			    &((struct sockaddr_in *)(sa))->sin_addr,
			    sizeof(struct in6_addr));
			break;
		case AF_INET6:
			sa->sa_len = sizeof(struct sockaddr_in6);
			bcopy(&src->mask.ipa,
			    &((struct sockaddr_in6 *)sa)->sin6_addr,
			    sizeof(struct in6_addr));
			break;
		}
		if (getnameinfo(sa, sa->sa_len, mask, sizeof(mask), NULL, 0,
		    NI_NUMERICHOST))
			errx(1, "could not get a numeric mask");

		if ((network = strdup(src->name)) == NULL)
			err(1, "ike_section_qmids: strdup");
		if ((p = strrchr(network, '/')) != NULL)
			*p = '\0';

		fprintf(fd, SET "[lid-%s]:ID-type=IPV%d_ADDR_SUBNET force\n",
		    src->name, ((src->af == AF_INET) ? 4 : 6));
		fprintf(fd, SET "[lid-%s]:Network=%s force\n", src->name,
		    network);
		fprintf(fd, SET "[lid-%s]:Netmask=%s force\n", src->name, mask);

		free(network);
	} else {
		fprintf(fd, SET "[lid-%s]:ID-type=IPV%d_ADDR force\n",
		    src->name, ((src->af == AF_INET) ? 4 : 6));
		fprintf(fd, SET "[lid-%s]:Address=%s force\n", src->name,
		    src->name);
	}
	if (dst->netaddress) {
		bzero(&sas, sizeof(struct sockaddr_storage));
		bzero(mask, sizeof(mask));
		sa->sa_family = dst->af;
		switch (dst->af) {
		case AF_INET:
			sa->sa_len = sizeof(struct sockaddr_in);
			bcopy(&dst->mask.ipa,
			    &((struct sockaddr_in *)(sa))->sin_addr,
			    sizeof(struct in6_addr));
			break;
		case AF_INET6:
			sa->sa_len = sizeof(struct sockaddr_in6);
			bcopy(&dst->mask.ipa,
			    &((struct sockaddr_in6 *)(sa))->sin6_addr,
			    sizeof(struct in6_addr));
			break;
		}
		if (getnameinfo(sa, sa->sa_len, mask, sizeof(mask), NULL, 0,
		    NI_NUMERICHOST))
			errx(1, "could not get a numeric mask");

		if ((network = strdup(dst->name)) == NULL)
			err(1, "ike_section_qmids: strdup");
		if ((p = strrchr(network, '/')) != NULL)
			*p = '\0';

		fprintf(fd, SET "[rid-%s]:ID-type=IPV%d_ADDR_SUBNET force\n",
		    dst->name, ((dst->af == AF_INET) ? 4 : 6));
		fprintf(fd, SET "[rid-%s]:Network=%s force\n", dst->name,
		    network);
		fprintf(fd, SET "[rid-%s]:Netmask=%s force\n", dst->name, mask);

		free(network);
	} else {
		fprintf(fd, SET "[rid-%s]:ID-type=IPV%d_ADDR force\n",
		    dst->name, ((dst->af == AF_INET) ? 4 : 6));
		fprintf(fd, SET "[rid-%s]:Address=%s force\n", dst->name,
		    dst->name);
	}
	if (proto) {
		fprintf(fd, SET "[lid-%s]:Protocol=%d force\n", src->name, proto);
		fprintf(fd, SET "[rid-%s]:Protocol=%d force\n", dst->name, proto);
	}
	if (sport)
		fprintf(fd, SET "[lid-%s]:Port=%d force\n", src->name,
		    ntohs(sport));
	if (dport)
		fprintf(fd, SET "[rid-%s]:Port=%d force\n", src->name,
		    ntohs(dport));
}

static int
ike_connect(u_int8_t mode, struct ipsec_addr_wrap *src,
    struct ipsec_addr_wrap *dst, FILE *fd)
{
	switch (mode) {
	case IKE_ACTIVE:
	case IKE_DYNAMIC:
		fprintf(fd, ADD "[Phase 2]:Connections=IPsec-%s-%s\n",
		    src->name, dst->name);
		break;
	case IKE_PASSIVE:
		fprintf(fd, ADD "[Phase 2]:Passive-Connections=IPsec-%s-%s\n",
		    src->name, dst->name);
		break;
	default:
		return (-1);
	}
	return (0);
}

static int
ike_gen_config(struct ipsec_rule *r, FILE *fd)
{
	ike_section_general(r, fd);
	ike_section_peer(r->peer, r->local, fd, r->ikeauth);
	if (ike_section_mm(r->peer, r->mmxfs, fd, r->ikeauth) == -1)
		return (-1);
	ike_section_ids(r->peer, r->auth, fd, r->ikemode);
	ike_section_ipsec(r->src, r->dst, r->peer, fd);
	if (ike_section_qm(r->src, r->dst, r->satype, r->tmode, r->qmxfs, fd)
	    == -1)
		return (-1);
	ike_section_qmids(r->proto, r->src, r->sport, r->dst, r->dport, fd);

	if (ike_connect(r->ikemode, r->src, r->dst, fd) == -1)
		return (-1);

	return (0);
}

static int
ike_delete_config(struct ipsec_rule *r, FILE *fd)
{
	switch (r->ikemode) {
	case IKE_ACTIVE:
	case IKE_DYNAMIC:
		fprintf(fd, "t IPsec-%s-%s\n", r->src->name, r->dst->name);
		break;
	case IKE_PASSIVE:
		fprintf(fd, DELETE "[Phase 2]\n");
		fprintf(fd, "t IPsec-%s-%s\n", r->src->name, r->dst->name);
		break;
	default:
		return (-1);
	}

	if (r->peer) {
		fprintf(fd, DELETE "[peer-%s]\n", r->peer->name);
		fprintf(fd, DELETE "[mm-%s]\n", r->peer->name);
	}
	if (r->auth) {
		if (r->auth->srcid)
			fprintf(fd, DELETE "[%s-ID]\n", r->auth->srcid);
		if (r->auth->dstid)
			fprintf(fd, DELETE "[%s-ID]\n", r->auth->dstid);
	}
	fprintf(fd, DELETE "[IPsec-%s-%s]\n", r->src->name, r->dst->name);
	fprintf(fd, DELETE "[qm-%s-%s]\n", r->src->name, r->dst->name);
	fprintf(fd, DELETE "[lid-%s]\n", r->src->name);
	fprintf(fd, DELETE "[rid-%s]\n", r->dst->name);

	return (0);
}

int
ike_print_config(struct ipsec_rule *r, int opts)
{
	if (opts & IPSECCTL_OPT_DELETE)
		return (ike_delete_config(r, stdout));
	else
		return (ike_gen_config(r, stdout));
}

int
ike_ipsec_establish(int action, struct ipsec_rule *r)
{
	struct stat	 sb;
	FILE		*fdp;
	int		 fd, ret = 0;

	if ((fd = open(ISAKMPD_FIFO, O_WRONLY)) == -1)
		err(1, "ike_ipsec_establish: open(%s)", ISAKMPD_FIFO);
	if (fstat(fd, &sb) == -1)
		err(1, "ike_ipsec_establish: fstat(%s)", ISAKMPD_FIFO);
	if (!S_ISFIFO(sb.st_mode))
		errx(1, "ike_ipsec_establish: %s not a fifo", ISAKMPD_FIFO);
	if ((fdp = fdopen(fd, "w")) == NULL)
		err(1, "ike_ipsec_establish: fdopen(%s)", ISAKMPD_FIFO);

	switch (action) {
	case ACTION_ADD:
		ret = ike_gen_config(r, fdp);
		break;
	case ACTION_DELETE:
		ret = ike_delete_config(r, fdp);
		break;
	default:
		ret = -1;
	}

	fclose(fdp);
	return (ret);
}