af_key.c

linux 内核源代码

{
	struct sk_buff *skb;
	int size;

	size = pfkey_xfrm_policy2msg_size(xp);

	skb =  alloc_skb(size + 16, GFP_ATOMIC);
	if (skb == NULL)
		return ERR_PTR(-ENOBUFS);

	return skb;
}

static int pfkey_xfrm_policy2msg(struct sk_buff *skb, struct xfrm_policy *xp, int dir)
{
	struct sadb_msg *hdr;
	struct sadb_address *addr;
	struct sadb_lifetime *lifetime;
	struct sadb_x_policy *pol;
	struct sockaddr_in   *sin;
	struct sadb_x_sec_ctx *sec_ctx;
	struct xfrm_sec_ctx *xfrm_ctx;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	struct sockaddr_in6  *sin6;
#endif
	int i;
	int size;
	int sockaddr_size = pfkey_sockaddr_size(xp->family);
	int socklen = (xp->family == AF_INET ?
		       sizeof(struct sockaddr_in) :
		       sizeof(struct sockaddr_in6));

	size = pfkey_xfrm_policy2msg_size(xp);

	/* call should fill header later */
	hdr = (struct sadb_msg *) skb_put(skb, sizeof(struct sadb_msg));
	memset(hdr, 0, size);	/* XXX do we need this ? */

	/* src address */
	addr = (struct sadb_address*) skb_put(skb,
					      sizeof(struct sadb_address)+sockaddr_size);
	addr->sadb_address_len =
		(sizeof(struct sadb_address)+sockaddr_size)/
			sizeof(uint64_t);
	addr->sadb_address_exttype = SADB_EXT_ADDRESS_SRC;
	addr->sadb_address_proto = pfkey_proto_from_xfrm(xp->selector.proto);
	addr->sadb_address_prefixlen = xp->selector.prefixlen_s;
	addr->sadb_address_reserved = 0;
	/* src address */
	if (xp->family == AF_INET) {
		sin = (struct sockaddr_in *) (addr + 1);
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = xp->selector.saddr.a4;
		sin->sin_port = xp->selector.sport;
		memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
	}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	else if (xp->family == AF_INET6) {
		sin6 = (struct sockaddr_in6 *) (addr + 1);
		sin6->sin6_family = AF_INET6;
		sin6->sin6_port = xp->selector.sport;
		sin6->sin6_flowinfo = 0;
		memcpy(&sin6->sin6_addr, xp->selector.saddr.a6,
		       sizeof(struct in6_addr));
		sin6->sin6_scope_id = 0;
	}
#endif
	else
		BUG();

	/* dst address */
	addr = (struct sadb_address*) skb_put(skb,
					      sizeof(struct sadb_address)+sockaddr_size);
	addr->sadb_address_len =
		(sizeof(struct sadb_address)+sockaddr_size)/
			sizeof(uint64_t);
	addr->sadb_address_exttype = SADB_EXT_ADDRESS_DST;
	addr->sadb_address_proto = pfkey_proto_from_xfrm(xp->selector.proto);
	addr->sadb_address_prefixlen = xp->selector.prefixlen_d;
	addr->sadb_address_reserved = 0;
	if (xp->family == AF_INET) {
		sin = (struct sockaddr_in *) (addr + 1);
		sin->sin_family = AF_INET;
		sin->sin_addr.s_addr = xp->selector.daddr.a4;
		sin->sin_port = xp->selector.dport;
		memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
	}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
	else if (xp->family == AF_INET6) {
		sin6 = (struct sockaddr_in6 *) (addr + 1);
		sin6->sin6_family = AF_INET6;
		sin6->sin6_port = xp->selector.dport;
		sin6->sin6_flowinfo = 0;
		memcpy(&sin6->sin6_addr, xp->selector.daddr.a6,
		       sizeof(struct in6_addr));
		sin6->sin6_scope_id = 0;
	}
#endif
	else
		BUG();

	/* hard time */
	lifetime = (struct sadb_lifetime *)  skb_put(skb,
						     sizeof(struct sadb_lifetime));
	lifetime->sadb_lifetime_len =
		sizeof(struct sadb_lifetime)/sizeof(uint64_t);
	lifetime->sadb_lifetime_exttype = SADB_EXT_LIFETIME_HARD;
	lifetime->sadb_lifetime_allocations =  _X2KEY(xp->lft.hard_packet_limit);
	lifetime->sadb_lifetime_bytes = _X2KEY(xp->lft.hard_byte_limit);
	lifetime->sadb_lifetime_addtime = xp->lft.hard_add_expires_seconds;
	lifetime->sadb_lifetime_usetime = xp->lft.hard_use_expires_seconds;
	/* soft time */
	lifetime = (struct sadb_lifetime *)  skb_put(skb,
						     sizeof(struct sadb_lifetime));
	lifetime->sadb_lifetime_len =
		sizeof(struct sadb_lifetime)/sizeof(uint64_t);
	lifetime->sadb_lifetime_exttype = SADB_EXT_LIFETIME_SOFT;
	lifetime->sadb_lifetime_allocations =  _X2KEY(xp->lft.soft_packet_limit);
	lifetime->sadb_lifetime_bytes = _X2KEY(xp->lft.soft_byte_limit);
	lifetime->sadb_lifetime_addtime = xp->lft.soft_add_expires_seconds;
	lifetime->sadb_lifetime_usetime = xp->lft.soft_use_expires_seconds;
	/* current time */
	lifetime = (struct sadb_lifetime *)  skb_put(skb,
						     sizeof(struct sadb_lifetime));
	lifetime->sadb_lifetime_len =
		sizeof(struct sadb_lifetime)/sizeof(uint64_t);
	lifetime->sadb_lifetime_exttype = SADB_EXT_LIFETIME_CURRENT;
	lifetime->sadb_lifetime_allocations = xp->curlft.packets;
	lifetime->sadb_lifetime_bytes = xp->curlft.bytes;
	lifetime->sadb_lifetime_addtime = xp->curlft.add_time;
	lifetime->sadb_lifetime_usetime = xp->curlft.use_time;

	pol = (struct sadb_x_policy *)  skb_put(skb, sizeof(struct sadb_x_policy));
	pol->sadb_x_policy_len = sizeof(struct sadb_x_policy)/sizeof(uint64_t);
	pol->sadb_x_policy_exttype = SADB_X_EXT_POLICY;
	pol->sadb_x_policy_type = IPSEC_POLICY_DISCARD;
	if (xp->action == XFRM_POLICY_ALLOW) {
		if (xp->xfrm_nr)
			pol->sadb_x_policy_type = IPSEC_POLICY_IPSEC;
		else
			pol->sadb_x_policy_type = IPSEC_POLICY_NONE;
	}
	pol->sadb_x_policy_dir = dir+1;
	pol->sadb_x_policy_id = xp->index;
	pol->sadb_x_policy_priority = xp->priority;

	for (i=0; i<xp->xfrm_nr; i++) {
		struct sadb_x_ipsecrequest *rq;
		struct xfrm_tmpl *t = xp->xfrm_vec + i;
		int req_size;
		int mode;

		req_size = sizeof(struct sadb_x_ipsecrequest);
		if (t->mode == XFRM_MODE_TUNNEL)
			req_size += ((t->encap_family == AF_INET ?
				     sizeof(struct sockaddr_in) :
				     sizeof(struct sockaddr_in6)) * 2);
		else
			size -= 2*socklen;
		rq = (void*)skb_put(skb, req_size);
		pol->sadb_x_policy_len += req_size/8;
		memset(rq, 0, sizeof(*rq));
		rq->sadb_x_ipsecrequest_len = req_size;
		rq->sadb_x_ipsecrequest_proto = t->id.proto;
		if ((mode = pfkey_mode_from_xfrm(t->mode)) < 0)
			return -EINVAL;
		rq->sadb_x_ipsecrequest_mode = mode;
		rq->sadb_x_ipsecrequest_level = IPSEC_LEVEL_REQUIRE;
		if (t->reqid)
			rq->sadb_x_ipsecrequest_level = IPSEC_LEVEL_UNIQUE;
		if (t->optional)
			rq->sadb_x_ipsecrequest_level = IPSEC_LEVEL_USE;
		rq->sadb_x_ipsecrequest_reqid = t->reqid;
		if (t->mode == XFRM_MODE_TUNNEL) {
			switch (t->encap_family) {
			case AF_INET:
				sin = (void*)(rq+1);
				sin->sin_family = AF_INET;
				sin->sin_addr.s_addr = t->saddr.a4;
				sin->sin_port = 0;
				memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
				sin++;
				sin->sin_family = AF_INET;
				sin->sin_addr.s_addr = t->id.daddr.a4;
				sin->sin_port = 0;
				memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
				break;
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
			case AF_INET6:
				sin6 = (void*)(rq+1);
				sin6->sin6_family = AF_INET6;
				sin6->sin6_port = 0;
				sin6->sin6_flowinfo = 0;
				memcpy(&sin6->sin6_addr, t->saddr.a6,
				       sizeof(struct in6_addr));
				sin6->sin6_scope_id = 0;

				sin6++;
				sin6->sin6_family = AF_INET6;
				sin6->sin6_port = 0;
				sin6->sin6_flowinfo = 0;
				memcpy(&sin6->sin6_addr, t->id.daddr.a6,
				       sizeof(struct in6_addr));
				sin6->sin6_scope_id = 0;
				break;
#endif
			default:
				break;
			}
		}
	}

	/* security context */
	if ((xfrm_ctx = xp->security)) {
		int ctx_size = pfkey_xfrm_policy2sec_ctx_size(xp);

		sec_ctx = (struct sadb_x_sec_ctx *) skb_put(skb, ctx_size);
		sec_ctx->sadb_x_sec_len = ctx_size / sizeof(uint64_t);
		sec_ctx->sadb_x_sec_exttype = SADB_X_EXT_SEC_CTX;
		sec_ctx->sadb_x_ctx_doi = xfrm_ctx->ctx_doi;
		sec_ctx->sadb_x_ctx_alg = xfrm_ctx->ctx_alg;
		sec_ctx->sadb_x_ctx_len = xfrm_ctx->ctx_len;
		memcpy(sec_ctx + 1, xfrm_ctx->ctx_str,
		       xfrm_ctx->ctx_len);
	}

	hdr->sadb_msg_len = size / sizeof(uint64_t);
	hdr->sadb_msg_reserved = atomic_read(&xp->refcnt);

	return 0;
}

static int key_notify_policy(struct xfrm_policy *xp, int dir, struct km_event *c)
{
	struct sk_buff *out_skb;
	struct sadb_msg *out_hdr;
	int err;

	out_skb = pfkey_xfrm_policy2msg_prep(xp);
	if (IS_ERR(out_skb)) {
		err = PTR_ERR(out_skb);
		goto out;
	}
	err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
	if (err < 0)
		return err;

	out_hdr = (struct sadb_msg *) out_skb->data;
	out_hdr->sadb_msg_version = PF_KEY_V2;

	if (c->data.byid && c->event == XFRM_MSG_DELPOLICY)
		out_hdr->sadb_msg_type = SADB_X_SPDDELETE2;
	else
		out_hdr->sadb_msg_type = event2poltype(c->event);
	out_hdr->sadb_msg_errno = 0;
	out_hdr->sadb_msg_seq = c->seq;
	out_hdr->sadb_msg_pid = c->pid;
	pfkey_broadcast(out_skb, GFP_ATOMIC, BROADCAST_ALL, NULL);
out:
	return 0;

}

static int pfkey_spdadd(struct sock *sk, struct sk_buff *skb, struct sadb_msg *hdr, void **ext_hdrs)
{
	int err = 0;
	struct sadb_lifetime *lifetime;
	struct sadb_address *sa;
	struct sadb_x_policy *pol;
	struct xfrm_policy *xp;
	struct km_event c;
	struct sadb_x_sec_ctx *sec_ctx;

	if (!present_and_same_family(ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
				     ext_hdrs[SADB_EXT_ADDRESS_DST-1]) ||
	    !ext_hdrs[SADB_X_EXT_POLICY-1])
		return -EINVAL;

	pol = ext_hdrs[SADB_X_EXT_POLICY-1];
	if (pol->sadb_x_policy_type > IPSEC_POLICY_IPSEC)
		return -EINVAL;
	if (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir >= IPSEC_DIR_MAX)
		return -EINVAL;

	xp = xfrm_policy_alloc(GFP_KERNEL);
	if (xp == NULL)
		return -ENOBUFS;

	xp->action = (pol->sadb_x_policy_type == IPSEC_POLICY_DISCARD ?
		      XFRM_POLICY_BLOCK : XFRM_POLICY_ALLOW);
	xp->priority = pol->sadb_x_policy_priority;

	sa = ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
	xp->family = pfkey_sadb_addr2xfrm_addr(sa, &xp->selector.saddr);
	if (!xp->family) {
		err = -EINVAL;
		goto out;
	}
	xp->selector.family = xp->family;
	xp->selector.prefixlen_s = sa->sadb_address_prefixlen;
	xp->selector.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	xp->selector.sport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (xp->selector.sport)
		xp->selector.sport_mask = htons(0xffff);

	sa = ext_hdrs[SADB_EXT_ADDRESS_DST-1],
	pfkey_sadb_addr2xfrm_addr(sa, &xp->selector.daddr);
	xp->selector.prefixlen_d = sa->sadb_address_prefixlen;

	/* Amusing, we set this twice.  KAME apps appear to set same value
	 * in both addresses.
	 */
	xp->selector.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);

	xp->selector.dport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (xp->selector.dport)
		xp->selector.dport_mask = htons(0xffff);

	sec_ctx = (struct sadb_x_sec_ctx *) ext_hdrs[SADB_X_EXT_SEC_CTX-1];
	if (sec_ctx != NULL) {
		struct xfrm_user_sec_ctx *uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx);

		if (!uctx) {
			err = -ENOBUFS;
			goto out;
		}

		err = security_xfrm_policy_alloc(xp, uctx);
		kfree(uctx);

		if (err)
			goto out;
	}

	xp->lft.soft_byte_limit = XFRM_INF;
	xp->lft.hard_byte_limit = XFRM_INF;
	xp->lft.soft_packet_limit = XFRM_INF;
	xp->lft.hard_packet_limit = XFRM_INF;
	if ((lifetime = ext_hdrs[SADB_EXT_LIFETIME_HARD-1]) != NULL) {
		xp->lft.hard_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
		xp->lft.hard_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
		xp->lft.hard_add_expires_seconds = lifetime->sadb_lifetime_addtime;
		xp->lft.hard_use_expires_seconds = lifetime->sadb_lifetime_usetime;
	}
	if ((lifetime = ext_hdrs[SADB_EXT_LIFETIME_SOFT-1]) != NULL) {
		xp->lft.soft_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
		xp->lft.soft_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
		xp->lft.soft_add_expires_seconds = lifetime->sadb_lifetime_addtime;
		xp->lft.soft_use_expires_seconds = lifetime->sadb_lifetime_usetime;
	}
	xp->xfrm_nr = 0;
	if (pol->sadb_x_policy_type == IPSEC_POLICY_IPSEC &&
	    (err = parse_ipsecrequests(xp, pol)) < 0)
		goto out;

	err = xfrm_policy_insert(pol->sadb_x_policy_dir-1, xp,
				 hdr->sadb_msg_type != SADB_X_SPDUPDATE);

	xfrm_audit_policy_add(xp, err ? 0 : 1,
			     audit_get_loginuid(current->audit_context), 0);

	if (err)
		goto out;

	if (hdr->sadb_msg_type == SADB_X_SPDUPDATE)
		c.event = XFRM_MSG_UPDPOLICY;
	else
		c.event = XFRM_MSG_NEWPOLICY;

	c.seq = hdr->sadb_msg_seq;
	c.pid = hdr->sadb_msg_pid;

	km_policy_notify(xp, pol->sadb_x_policy_dir-1, &c);
	xfrm_pol_put(xp);
	return 0;

out:
	security_xfrm_policy_free(xp);
	kfree(xp);
	return err;
}

static int pfkey_spddelete(struct sock *sk, struct sk_buff *skb, struct sadb_msg *hdr, void **ext_hdrs)
{
	int err;
	struct sadb_address *sa;
	struct sadb_x_policy *pol;
	struct xfrm_policy *xp, tmp;
	struct xfrm_selector sel;
	struct km_event c;
	struct sadb_x_sec_ctx *sec_ctx;

	if (!present_and_same_family(ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
				     ext_hdrs[SADB_EXT_ADDRESS_DST-1]) ||
	    !ext_hdrs[SADB_X_EXT_POLICY-1])
		return -EINVAL;

	pol = ext_hdrs[SADB_X_EXT_POLICY-1];
	if (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir >= IPSEC_DIR_MAX)
		return -EINVAL;

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

	sa = ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
	sel.family = pfkey_sadb_addr2xfrm_addr(sa, &sel.saddr);
	sel.prefixlen_s = sa->sadb_address_prefixlen;
	sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	sel.sport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (sel.sport)
		sel.sport_mask = htons(0xffff);

	sa = ext_hdrs[SADB_EXT_ADDRESS_DST-1],
	pfkey_sadb_addr2xfrm_addr(sa, &sel.daddr);
	sel.prefixlen_d = sa->sadb_address_prefixlen;
	sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	sel.dport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (sel.dport)
		sel.dport_mask = htons(0xffff);

	sec_ctx = (struct sadb_x_sec_ctx *) ext_hdrs[SADB_X_EXT_SEC_CTX-1];
	memset(&tmp, 0, sizeof(struct xfrm_policy));

	if (sec_ctx != NULL) {
		struct xfrm_user_sec_ctx *uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx);

		if (!uctx)
			return -ENOMEM;

		err = security_xfrm_policy_alloc(&tmp, uctx);
		kfree(uctx);

		if (err)
			return err;
	}

	xp = xfrm_policy_bysel_ctx(XFRM_POLICY_TYPE_MAIN, pol->sadb_x_policy_dir-1,
				   &sel, tmp.security, 1, &err);
	security_xfrm_policy_free(&tmp);

	if (xp == NULL)
		return -ENOENT;

	xfrm_audit_policy_delete(xp, err ? 0 : 1,
				audit_get_loginuid(current->audit_context), 0);

	if (err)
		goto out;

	c.seq = hdr->sadb_msg_seq;
	c.pid = hdr->sadb_msg_pid;
	c.event = XFRM_MSG_DELPOLICY;
	km_policy_notify(xp, pol->sadb_x_policy_dir-1, &c);

out:
	xfrm_pol_put(xp);
	return err;
}

static int key_pol_get_resp(struct sock *sk, struct xfrm_policy *xp, struct sadb_msg *hdr, int dir)
{
	int err;
	struct sk_buff *out_skb;
	struct sadb_msg *out_hdr;
	err = 0;

	out_skb = pfkey_xfrm_policy2msg_prep(xp);
	if (IS_ERR(out_skb)) {
		err =  PTR_ERR(out_skb);
		goto out;
	}
	err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
	if (err < 0)
		goto out;

	out_hdr = (struct sadb_msg *) out_skb->data;
	out_hdr->sadb_msg_version = hdr->sadb_msg_version;
	out_hdr->sadb_msg_type = hdr->sadb_msg_type;
	out_hdr->sadb_msg_