text: /* xfrm_user.c: User interface to configure xfrm engine.
   *
   * Copyright (C) 2002 David S. Miller (davem@redhat.com)
   *
   * Changes:
   *	Mitsuru KANDA @USAGI
   * 	Kazunori MIYAZAWA @USAGI
   * 	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
   * 		IPv6 support
   *
   */
  
  #include <linux/crypto.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/socket.h>
  #include <linux/string.h>
  #include <linux/net.h>
  #include <linux/skbuff.h>
  #include <linux/pfkeyv2.h>
  #include <linux/ipsec.h>
  #include <linux/init.h>
  #include <linux/security.h>
  #include <net/sock.h>
  #include <net/xfrm.h>
  #include <net/netlink.h>
  #include <net/ah.h>
  #include <asm/uaccess.h>
  #if IS_ENABLED(CONFIG_IPV6)
  #include <linux/in6.h>
  #endif
  
  static inline int aead_len(struct xfrm_algo_aead *alg)
  {
  	return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
  }
  
  static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
  {
  	struct nlattr *rt = attrs[type];
  	struct xfrm_algo *algp;
  
  	if (!rt)
  		return 0;
  
  	algp = nla_data(rt);
  	if (nla_len(rt) < xfrm_alg_len(algp))
  		return -EINVAL;
  
  	switch (type) {
  	case XFRMA_ALG_AUTH:
  	case XFRMA_ALG_CRYPT:
  	case XFRMA_ALG_COMP:
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	algp->alg_name[CRYPTO_MAX_ALG_NAME - 1] = '\0';
  	return 0;
  }
  
  static int verify_auth_trunc(struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_ALG_AUTH_TRUNC];
  	struct xfrm_algo_auth *algp;
  
  	if (!rt)
  		return 0;
  
  	algp = nla_data(rt);
  	if (nla_len(rt) < xfrm_alg_auth_len(algp))
  		return -EINVAL;
  
  	algp->alg_name[CRYPTO_MAX_ALG_NAME - 1] = '\0';
  	return 0;
  }
  
  static int verify_aead(struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_ALG_AEAD];
  	struct xfrm_algo_aead *algp;
  
  	if (!rt)
  		return 0;
  
  	algp = nla_data(rt);
  	if (nla_len(rt) < aead_len(algp))
  		return -EINVAL;
  
  	algp->alg_name[CRYPTO_MAX_ALG_NAME - 1] = '\0';
  	return 0;
  }
  
  static void verify_one_addr(struct nlattr **attrs, enum xfrm_attr_type_t type,
  			   xfrm_address_t **addrp)
  {
  	struct nlattr *rt = attrs[type];
  
  	if (rt && addrp)
  		*addrp = nla_data(rt);
  }
  
  static inline int verify_sec_ctx_len(struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_SEC_CTX];
  	struct xfrm_user_sec_ctx *uctx;
  
  	if (!rt)
  		return 0;
  
  	uctx = nla_data(rt);
  	if (uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len))
  		return -EINVAL;
  
  	return 0;
  }
  
  static inline int verify_replay(struct xfrm_usersa_info *p,
  				struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_REPLAY_ESN_VAL];
  	struct xfrm_replay_state_esn *rs;
  
  	if (p->flags & XFRM_STATE_ESN) {
  		if (!rt)
  			return -EINVAL;
  
  		rs = nla_data(rt);
  
  		if (rs->bmp_len > XFRMA_REPLAY_ESN_MAX / sizeof(rs->bmp[0]) / 8)
  			return -EINVAL;
  
  		if (nla_len(rt) < xfrm_replay_state_esn_len(rs) &&
  		    nla_len(rt) != sizeof(*rs))
  			return -EINVAL;
  	}
  
  	if (!rt)
  		return 0;
  
  	if (p->id.proto != IPPROTO_ESP)
  		return -EINVAL;
  
  	if (p->replay_window != 0)
  		return -EINVAL;
  
  	return 0;
  }
  
  static int verify_newsa_info(struct xfrm_usersa_info *p,
  			     struct nlattr **attrs)
  {
  	int err;
  
  	err = -EINVAL;
  	switch (p->family) {
  	case AF_INET:
  		break;
  
  	case AF_INET6:
  #if IS_ENABLED(CONFIG_IPV6)
  		break;
  #else
  		err = -EAFNOSUPPORT;
  		goto out;
  #endif
  
  	default:
  		goto out;
  	}
  
  	err = -EINVAL;
  	switch (p->id.proto) {
  	case IPPROTO_AH:
  		if ((!attrs[XFRMA_ALG_AUTH]	&&
  		     !attrs[XFRMA_ALG_AUTH_TRUNC]) ||
  		    attrs[XFRMA_ALG_AEAD]	||
  		    attrs[XFRMA_ALG_CRYPT]	||
  		    attrs[XFRMA_ALG_COMP]	||
  		    attrs[XFRMA_TFCPAD])
  			goto out;
  		break;
  
  	case IPPROTO_ESP:
  		if (attrs[XFRMA_ALG_COMP])
  			goto out;
  		if (!attrs[XFRMA_ALG_AUTH] &&
  		    !attrs[XFRMA_ALG_AUTH_TRUNC] &&
  		    !attrs[XFRMA_ALG_CRYPT] &&
  		    !attrs[XFRMA_ALG_AEAD])
  			goto out;
  		if ((attrs[XFRMA_ALG_AUTH] ||
  		     attrs[XFRMA_ALG_AUTH_TRUNC] ||
  		     attrs[XFRMA_ALG_CRYPT]) &&
  		    attrs[XFRMA_ALG_AEAD])
  			goto out;
  		if (attrs[XFRMA_TFCPAD] &&
  		    p->mode != XFRM_MODE_TUNNEL)
  			goto out;
  		break;
  
  	case IPPROTO_COMP:
  		if (!attrs[XFRMA_ALG_COMP]	||
  		    attrs[XFRMA_ALG_AEAD]	||
  		    attrs[XFRMA_ALG_AUTH]	||
  		    attrs[XFRMA_ALG_AUTH_TRUNC]	||
  		    attrs[XFRMA_ALG_CRYPT]	||
  		    attrs[XFRMA_TFCPAD])
  			goto out;
  		break;
  
  #if IS_ENABLED(CONFIG_IPV6)
  	case IPPROTO_DSTOPTS:
  	case IPPROTO_ROUTING:
  		if (attrs[XFRMA_ALG_COMP]	||
  		    attrs[XFRMA_ALG_AUTH]	||
  		    attrs[XFRMA_ALG_AUTH_TRUNC]	||
  		    attrs[XFRMA_ALG_AEAD]	||
  		    attrs[XFRMA_ALG_CRYPT]	||
  		    attrs[XFRMA_ENCAP]		||
  		    attrs[XFRMA_SEC_CTX]	||
  		    attrs[XFRMA_TFCPAD]		||
  		    !attrs[XFRMA_COADDR])
  			goto out;
  		break;
  #endif
  
  	default:
  		goto out;
  	}
  
  	if ((err = verify_aead(attrs)))
  		goto out;
  	if ((err = verify_auth_trunc(attrs)))
  		goto out;
  	if ((err = verify_one_alg(attrs, XFRMA_ALG_AUTH)))
  		goto out;
  	if ((err = verify_one_alg(attrs, XFRMA_ALG_CRYPT)))
  		goto out;
  	if ((err = verify_one_alg(attrs, XFRMA_ALG_COMP)))
  		goto out;
  	if ((err = verify_sec_ctx_len(attrs)))
  		goto out;
  	if ((err = verify_replay(p, attrs)))
  		goto out;
  
  	err = -EINVAL;
  	switch (p->mode) {
  	case XFRM_MODE_TRANSPORT:
  	case XFRM_MODE_TUNNEL:
  	case XFRM_MODE_ROUTEOPTIMIZATION:
  	case XFRM_MODE_BEET:
  		break;
  
  	default:
  		goto out;
  	}
  
  	err = 0;
  
  out:
  	return err;
  }
  
  static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
  			   struct xfrm_algo_desc *(*get_byname)(const char *, int),
  			   struct nlattr *rta)
  {
  	struct xfrm_algo *p, *ualg;
  	struct xfrm_algo_desc *algo;
  
  	if (!rta)
  		return 0;
  
  	ualg = nla_data(rta);
  
  	algo = get_byname(ualg->alg_name, 1);
  	if (!algo)
  		return -ENOSYS;
  	*props = algo->desc.sadb_alg_id;
  
  	p = kmemdup(ualg, xfrm_alg_len(ualg), GFP_KERNEL);
  	if (!p)
  		return -ENOMEM;
  
  	strcpy(p->alg_name, algo->name);
  	*algpp = p;
  	return 0;
  }
  
  static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
  		       struct nlattr *rta)
  {
  	struct xfrm_algo *ualg;
  	struct xfrm_algo_auth *p;
  	struct xfrm_algo_desc *algo;
  
  	if (!rta)
  		return 0;
  
  	ualg = nla_data(rta);
  
  	algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
  	if (!algo)
  		return -ENOSYS;
  	*props = algo->desc.sadb_alg_id;
  
  	p = kmalloc(sizeof(*p) + (ualg->alg_key_len + 7) / 8, GFP_KERNEL);
  	if (!p)
  		return -ENOMEM;
  
  	strcpy(p->alg_name, algo->name);
  	p->alg_key_len = ualg->alg_key_len;
  	p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;
  	memcpy(p->alg_key, ualg->alg_key, (ualg->alg_key_len + 7) / 8);
  
  	*algpp = p;
  	return 0;
  }
  
  static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
  			     struct nlattr *rta)
  {
  	struct xfrm_algo_auth *p, *ualg;
  	struct xfrm_algo_desc *algo;
  
  	if (!rta)
  		return 0;
  
  	ualg = nla_data(rta);
  
  	algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
  	if (!algo)
  		return -ENOSYS;
  	if ((ualg->alg_trunc_len / 8) > MAX_AH_AUTH_LEN ||
  	    ualg->alg_trunc_len > algo->uinfo.auth.icv_fullbits)
  		return -EINVAL;
  	*props = algo->desc.sadb_alg_id;
  
  	p = kmemdup(ualg, xfrm_alg_auth_len(ualg), GFP_KERNEL);
  	if (!p)
  		return -ENOMEM;
  
  	strcpy(p->alg_name, algo->name);
  	if (!p->alg_trunc_len)
  		p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;
  
  	*algpp = p;
  	return 0;
  }
  
  static int attach_aead(struct xfrm_algo_aead **algpp, u8 *props,
  		       struct nlattr *rta)
  {
  	struct xfrm_algo_aead *p, *ualg;
  	struct xfrm_algo_desc *algo;
  
  	if (!rta)
  		return 0;
  
  	ualg = nla_data(rta);
  
  	algo = xfrm_aead_get_byname(ualg->alg_name, ualg->alg_icv_len, 1);
  	if (!algo)
  		return -ENOSYS;
  	*props = algo->desc.sadb_alg_id;
  
  	p = kmemdup(ualg, aead_len(ualg), GFP_KERNEL);
  	if (!p)
  		return -ENOMEM;
  
  	strcpy(p->alg_name, algo->name);
  	*algpp = p;
  	return 0;
  }
  
  static inline int xfrm_replay_verify_len(struct xfrm_replay_state_esn *replay_esn,
  					 struct nlattr *rp)
  {
  	struct xfrm_replay_state_esn *up;
  	int ulen;
  
  	if (!replay_esn || !rp)
  		return 0;
  
  	up = nla_data(rp);
  	ulen = xfrm_replay_state_esn_len(up);
  
  	if (nla_len(rp) < ulen || xfrm_replay_state_esn_len(replay_esn) != ulen)
  		return -EINVAL;
  
  	return 0;
  }
  
  static int xfrm_alloc_replay_state_esn(struct xfrm_replay_state_esn **replay_esn,
  				       struct xfrm_replay_state_esn **preplay_esn,
  				       struct nlattr *rta)
  {
  	struct xfrm_replay_state_esn *p, *pp, *up;
  	int klen, ulen;
  
  	if (!rta)
  		return 0;
  
  	up = nla_data(rta);
  	klen = xfrm_replay_state_esn_len(up);
  	ulen = nla_len(rta) >= klen ? klen : sizeof(*up);
  
  	p = kzalloc(klen, GFP_KERNEL);
  	if (!p)
  		return -ENOMEM;
  
  	pp = kzalloc(klen, GFP_KERNEL);
  	if (!pp) {
  		kfree(p);
  		return -ENOMEM;
  	}
  
  	memcpy(p, up, ulen);
  	memcpy(pp, up, ulen);
  
  	*replay_esn = p;
  	*preplay_esn = pp;
  
  	return 0;
  }
  
  static inline int xfrm_user_sec_ctx_size(struct xfrm_sec_ctx *xfrm_ctx)
  {
  	int len = 0;
  
  	if (xfrm_ctx) {
  		len += sizeof(struct xfrm_user_sec_ctx);
  		len += xfrm_ctx->ctx_len;
  	}
  	return len;
  }
  
  static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
  {
  	memcpy(&x->id, &p->id, sizeof(x->id));
  	memcpy(&x->sel, &p->sel, sizeof(x->sel));
  	memcpy(&x->lft, &p->lft, sizeof(x->lft));
  	x->props.mode = p->mode;
  	x->props.replay_window = min_t(unsigned int, p->replay_window,
  					sizeof(x->replay.bitmap) * 8);
  	x->props.reqid = p->reqid;
  	x->props.family = p->family;
  	memcpy(&x->props.saddr, &p->saddr, sizeof(x->props.saddr));
  	x->props.flags = p->flags;
  
  	if (!x->sel.family && !(p->flags & XFRM_STATE_AF_UNSPEC))
  		x->sel.family = p->family;
  }
  
  /*
   * someday when pfkey also has support, we could have the code
   * somehow made shareable and move it to xfrm_state.c - JHS
   *
  */
  static void xfrm_update_ae_params(struct xfrm_state *x, struct nlattr **attrs,
  				  int update_esn)
  {
  	struct nlattr *rp = attrs[XFRMA_REPLAY_VAL];
  	struct nlattr *re = update_esn ? attrs[XFRMA_REPLAY_ESN_VAL] : NULL;
  	struct nlattr *lt = attrs[XFRMA_LTIME_VAL];
  	struct nlattr *et = attrs[XFRMA_ETIMER_THRESH];
  	struct nlattr *rt = attrs[XFRMA_REPLAY_THRESH];
  
  	if (re) {
  		struct xfrm_replay_state_esn *replay_esn;
  		replay_esn = nla_data(re);
  		memcpy(x->replay_esn, replay_esn,
  		       xfrm_replay_state_esn_len(replay_esn));
  		memcpy(x->preplay_esn, replay_esn,
  		       xfrm_replay_state_esn_len(replay_esn));
  	}
  
  	if (rp) {
  		struct xfrm_replay_state *replay;
  		replay = nla_data(rp);
  		memcpy(&x->replay, replay, sizeof(*replay));
  		memcpy(&x->preplay, replay, sizeof(*replay));
  	}
  
  	if (lt) {
  		struct xfrm_lifetime_cur *ltime;
  		ltime = nla_data(lt);
  		x->curlft.bytes = ltime->bytes;
  		x->curlft.packets = ltime->packets;
  		x->curlft.add_time = ltime->add_time;
  		x->curlft.use_time = ltime->use_time;
  	}
  
  	if (et)
  		x->replay_maxage = nla_get_u32(et);
  
  	if (rt)
  		x->replay_maxdiff = nla_get_u32(rt);
  }
  
  static struct xfrm_state *xfrm_state_construct(struct net *net,
  					       struct xfrm_usersa_info *p,
  					       struct nlattr **attrs,
  					       int *errp)
  {
  	struct xfrm_state *x = xfrm_state_alloc(net);
  	int err = -ENOMEM;
  
  	if (!x)
  		goto error_no_put;
  
  	copy_from_user_state(x, p);
  
  	if (attrs[XFRMA_SA_EXTRA_FLAGS])
  		x->props.extra_flags = nla_get_u32(attrs[XFRMA_SA_EXTRA_FLAGS]);
  
  	if ((err = attach_aead(&x->aead, &x->props.ealgo,
  			       attrs[XFRMA_ALG_AEAD])))
  		goto error;
  	if ((err = attach_auth_trunc(&x->aalg, &x->props.aalgo,
  				     attrs[XFRMA_ALG_AUTH_TRUNC])))
  		goto error;
  	if (!x->props.aalgo) {
  		if ((err = attach_auth(&x->aalg, &x->props.aalgo,
  				       attrs[XFRMA_ALG_AUTH])))
  			goto error;
  	}
  	if ((err = attach_one_algo(&x->ealg, &x->props.ealgo,
  				   xfrm_ealg_get_byname,
  				   attrs[XFRMA_ALG_CRYPT])))
  		goto error;
  	if ((err = attach_one_algo(&x->calg, &x->props.calgo,
  				   xfrm_calg_get_byname,
  				   attrs[XFRMA_ALG_COMP])))
  		goto error;
  
  	if (attrs[XFRMA_ENCAP]) {
  		x->encap = kmemdup(nla_data(attrs[XFRMA_ENCAP]),
  				   sizeof(*x->encap), GFP_KERNEL);
  		if (x->encap == NULL)
  			goto error;
  	}
  
  	if (attrs[XFRMA_TFCPAD])
  		x->tfcpad = nla_get_u32(attrs[XFRMA_TFCPAD]);
  
  	if (attrs[XFRMA_COADDR]) {
  		x->coaddr = kmemdup(nla_data(attrs[XFRMA_COADDR]),
  				    sizeof(*x->coaddr), GFP_KERNEL);
  		if (x->coaddr == NULL)
  			goto error;
  	}
  
  	xfrm_mark_get(attrs, &x->mark);
  
  	err = __xfrm_init_state(x, false);
  	if (err)
  		goto error;
  
  	if (attrs[XFRMA_SEC_CTX] &&
  	    security_xfrm_state_alloc(x, nla_data(attrs[XFRMA_SEC_CTX])))
  		goto error;
  
  	if ((err = xfrm_alloc_replay_state_esn(&x->replay_esn, &x->preplay_esn,
  					       attrs[XFRMA_REPLAY_ESN_VAL])))
  		goto error;
  
  	x->km.seq = p->seq;
  	x->replay_maxdiff = net->xfrm.sysctl_aevent_rseqth;
  	/* sysctl_xfrm_aevent_etime is in 100ms units */
  	x->replay_maxage = (net->xfrm.sysctl_aevent_etime*HZ)/XFRM_AE_ETH_M;
  
  	if ((err = xfrm_init_replay(x)))
  		goto error;
  
  	/* override default values from above */
  	xfrm_update_ae_params(x, attrs, 0);
  
  	return x;
  
  error:
  	x->km.state = XFRM_STATE_DEAD;
  	xfrm_state_put(x);
  error_no_put:
  	*errp = err;
  	return NULL;
  }
  
  static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_usersa_info *p = nlmsg_data(nlh);
  	struct xfrm_state *x;
  	int err;
  	struct km_event c;
  	kuid_t loginuid = audit_get_loginuid(current);
  	u32 sessionid = audit_get_sessionid(current);
  	u32 sid;
  
  	err = verify_newsa_info(p, attrs);
  	if (err)
  		return err;
  
  	x = xfrm_state_construct(net, p, attrs, &err);
  	if (!x)
  		return err;
  
  	xfrm_state_hold(x);
  	if (nlh->nlmsg_type == XFRM_MSG_NEWSA)
  		err = xfrm_state_add(x);
  	else
  		err = xfrm_state_update(x);
  
  	security_task_getsecid(current, &sid);
  	xfrm_audit_state_add(x, err ? 0 : 1, loginuid, sessionid, sid);
  
  	if (err < 0) {
  		x->km.state = XFRM_STATE_DEAD;
  		__xfrm_state_put(x);
  		goto out;
  	}
  
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	c.event = nlh->nlmsg_type;
  
  	km_state_notify(x, &c);
  out:
  	xfrm_state_put(x);
  	return err;
  }
  
  static struct xfrm_state *xfrm_user_state_lookup(struct net *net,
  						 struct xfrm_usersa_id *p,
  						 struct nlattr **attrs,
  						 int *errp)
  {
  	struct xfrm_state *x = NULL;
  	struct xfrm_mark m;
  	int err;
  	u32 mark = xfrm_mark_get(attrs, &m);
  
  	if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY)) {
  		err = -ESRCH;
  		x = xfrm_state_lookup(net, mark, &p->daddr, p->spi, p->proto, p->family);
  	} else {
  		xfrm_address_t *saddr = NULL;
  
  		verify_one_addr(attrs, XFRMA_SRCADDR, &saddr);
  		if (!saddr) {
  			err = -EINVAL;
  			goto out;
  		}
  
  		err = -ESRCH;
  		x = xfrm_state_lookup_byaddr(net, mark,
  					     &p->daddr, saddr,
  					     p->proto, p->family);
  	}
  
   out:
  	if (!x && errp)
  		*errp = err;
  	return x;
  }
  
  static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state *x;
  	int err = -ESRCH;
  	struct km_event c;
  	struct xfrm_usersa_id *p = nlmsg_data(nlh);
  	kuid_t loginuid = audit_get_loginuid(current);
  	u32 sessionid = audit_get_sessionid(current);
  	u32 sid;
  
  	x = xfrm_user_state_lookup(net, p, attrs, &err);
  	if (x == NULL)
  		return err;
  
  	if ((err = security_xfrm_state_delete(x)) != 0)
  		goto out;
  
  	if (xfrm_state_kern(x)) {
  		err = -EPERM;
  		goto out;
  	}
  
  	err = xfrm_state_delete(x);
  
  	if (err < 0)
  		goto out;
  
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	c.event = nlh->nlmsg_type;
  	km_state_notify(x, &c);
  
  out:
  	security_task_getsecid(current, &sid);
  	xfrm_audit_state_delete(x, err ? 0 : 1, loginuid, sessionid, sid);
  	xfrm_state_put(x);
  	return err;
  }
  
  static void copy_to_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
  {
  	memset(p, 0, sizeof(*p));
  	memcpy(&p->id, &x->id, sizeof(p->id));
  	memcpy(&p->sel, &x->sel, sizeof(p->sel));
  	memcpy(&p->lft, &x->lft, sizeof(p->lft));
  	memcpy(&p->curlft, &x->curlft, sizeof(p->curlft));
  	memcpy(&p->stats, &x->stats, sizeof(p->stats));
  	memcpy(&p->saddr, &x->props.saddr, sizeof(p->saddr));
  	p->mode = x->props.mode;
  	p->replay_window = x->props.replay_window;
  	p->reqid = x->props.reqid;
  	p->family = x->props.family;
  	p->flags = x->props.flags;
  	p->seq = x->km.seq;
  }
  
  struct xfrm_dump_info {
  	struct sk_buff *in_skb;
  	struct sk_buff *out_skb;
  	u32 nlmsg_seq;
  	u16 nlmsg_flags;
  };
  
  static int copy_sec_ctx(struct xfrm_sec_ctx *s, struct sk_buff *skb)
  {
  	struct xfrm_user_sec_ctx *uctx;
  	struct nlattr *attr;
  	int ctx_size = sizeof(*uctx) + s->ctx_len;
  
  	attr = nla_reserve(skb, XFRMA_SEC_CTX, ctx_size);
  	if (attr == NULL)
  		return -EMSGSIZE;
  
  	uctx = nla_data(attr);
  	uctx->exttype = XFRMA_SEC_CTX;
  	uctx->len = ctx_size;
  	uctx->ctx_doi = s->ctx_doi;
  	uctx->ctx_alg = s->ctx_alg;
  	uctx->ctx_len = s->ctx_len;
  	memcpy(uctx + 1, s->ctx_str, s->ctx_len);
  
  	return 0;
  }
  
  static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff *skb)
  {
  	struct xfrm_algo *algo;
  	struct nlattr *nla;
  
  	nla = nla_reserve(skb, XFRMA_ALG_AUTH,
  			  sizeof(*algo) + (auth->alg_key_len + 7) / 8);
  	if (!nla)
  		return -EMSGSIZE;
  
  	algo = nla_data(nla);
  	strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name));
  	memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8);
  	algo->alg_key_len = auth->alg_key_len;
  
  	return 0;
  }
  
  /* Don't change this without updating xfrm_sa_len! */
  static int copy_to_user_state_extra(struct xfrm_state *x,
  				    struct xfrm_usersa_info *p,
  				    struct sk_buff *skb)
  {
  	int ret = 0;
  
  	copy_to_user_state(x, p);
  
  	if (x->props.extra_flags) {
  		ret = nla_put_u32(skb, XFRMA_SA_EXTRA_FLAGS,
  				  x->props.extra_flags);
  		if (ret)
  			goto out;
  	}
  
  	if (x->coaddr) {
  		ret = nla_put(skb, XFRMA_COADDR, sizeof(*x->coaddr), x->coaddr);
  		if (ret)
  			goto out;
  	}
  	if (x->lastused) {
  		ret = nla_put_u64(skb, XFRMA_LASTUSED, x->lastused);
  		if (ret)
  			goto out;
  	}
  	if (x->aead) {
  		ret = nla_put(skb, XFRMA_ALG_AEAD, aead_len(x->aead), x->aead);
  		if (ret)
  			goto out;
  	}
  	if (x->aalg) {
  		ret = copy_to_user_auth(x->aalg, skb);
  		if (!ret)
  			ret = nla_put(skb, XFRMA_ALG_AUTH_TRUNC,
  				      xfrm_alg_auth_len(x->aalg), x->aalg);
  		if (ret)
  			goto out;
  	}
  	if (x->ealg) {
  		ret = nla_put(skb, XFRMA_ALG_CRYPT, xfrm_alg_len(x->ealg), x->ealg);
  		if (ret)
  			goto out;
  	}
  	if (x->calg) {
  		ret = nla_put(skb, XFRMA_ALG_COMP, sizeof(*(x->calg)), x->calg);
  		if (ret)
  			goto out;
  	}
  	if (x->encap) {
  		ret = nla_put(skb, XFRMA_ENCAP, sizeof(*x->encap), x->encap);
  		if (ret)
  			goto out;
  	}
  	if (x->tfcpad) {
  		ret = nla_put_u32(skb, XFRMA_TFCPAD, x->tfcpad);
  		if (ret)
  			goto out;
  	}
  	ret = xfrm_mark_put(skb, &x->mark);
  	if (ret)
  		goto out;
  	if (x->replay_esn) {
  		ret = nla_put(skb, XFRMA_REPLAY_ESN_VAL,
  			      xfrm_replay_state_esn_len(x->replay_esn),
  			      x->replay_esn);
  		if (ret)
  			goto out;
  	}
  	if (x->security)
  		ret = copy_sec_ctx(x->security, skb);
  out:
  	return ret;
  }
  
  static int dump_one_state(struct xfrm_state *x, int count, void *ptr)
  {
  	struct xfrm_dump_info *sp = ptr;
  	struct sk_buff *in_skb = sp->in_skb;
  	struct sk_buff *skb = sp->out_skb;
  	struct xfrm_usersa_info *p;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, sp->nlmsg_seq,
  			XFRM_MSG_NEWSA, sizeof(*p), sp->nlmsg_flags);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	p = nlmsg_data(nlh);
  
  	err = copy_to_user_state_extra(x, p, skb);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  	nlmsg_end(skb, nlh);
  	return 0;
  }
  
  static int xfrm_dump_sa_done(struct netlink_callback *cb)
  {
  	struct xfrm_state_walk *walk = (struct xfrm_state_walk *) &cb->args[1];
  	xfrm_state_walk_done(walk);
  	return 0;
  }
  
  static int xfrm_dump_sa(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state_walk *walk = (struct xfrm_state_walk *) &cb->args[1];
  	struct xfrm_dump_info info;
  
  	BUILD_BUG_ON(sizeof(struct xfrm_state_walk) >
  		     sizeof(cb->args) - sizeof(cb->args[0]));
  
  	info.in_skb = cb->skb;
  	info.out_skb = skb;
  	info.nlmsg_seq = cb->nlh->nlmsg_seq;
  	info.nlmsg_flags = NLM_F_MULTI;
  
  	if (!cb->args[0]) {
  		cb->args[0] = 1;
  		xfrm_state_walk_init(walk, 0);
  	}
  
  	(void) xfrm_state_walk(net, walk, dump_one_state, &info);
  
  	return skb->len;
  }
  
  static struct sk_buff *xfrm_state_netlink(struct sk_buff *in_skb,
  					  struct xfrm_state *x, u32 seq)
  {
  	struct xfrm_dump_info info;
  	struct sk_buff *skb;
  	int err;
  
  	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
  	if (!skb)
  		return ERR_PTR(-ENOMEM);
  
  	info.in_skb = in_skb;
  	info.out_skb = skb;
  	info.nlmsg_seq = seq;
  	info.nlmsg_flags = 0;
  
  	err = dump_one_state(x, 0, &info);
  	if (err) {
  		kfree_skb(skb);
  		return ERR_PTR(err);
  	}
  
  	return skb;
  }
  
  static inline size_t xfrm_spdinfo_msgsize(void)
  {
  	return NLMSG_ALIGN(4)
  	       + nla_total_size(sizeof(struct xfrmu_spdinfo))
  	       + nla_total_size(sizeof(struct xfrmu_spdhinfo));
  }
  
  static int build_spdinfo(struct sk_buff *skb, struct net *net,
  			 u32 portid, u32 seq, u32 flags)
  {
  	struct xfrmk_spdinfo si;
  	struct xfrmu_spdinfo spc;
  	struct xfrmu_spdhinfo sph;
  	struct nlmsghdr *nlh;
  	int err;
  	u32 *f;
  
  	nlh = nlmsg_put(skb, portid, seq, XFRM_MSG_NEWSPDINFO, sizeof(u32), 0);
  	if (nlh == NULL) /* shouldn't really happen ... */
  		return -EMSGSIZE;
  
  	f = nlmsg_data(nlh);
  	*f = flags;
  	xfrm_spd_getinfo(net, &si);
  	spc.incnt = si.incnt;
  	spc.outcnt = si.outcnt;
  	spc.fwdcnt = si.fwdcnt;
  	spc.inscnt = si.inscnt;
  	spc.outscnt = si.outscnt;
  	spc.fwdscnt = si.fwdscnt;
  	sph.spdhcnt = si.spdhcnt;
  	sph.spdhmcnt = si.spdhmcnt;
  
  	err = nla_put(skb, XFRMA_SPD_INFO, sizeof(spc), &spc);
  	if (!err)
  		err = nla_put(skb, XFRMA_SPD_HINFO, sizeof(sph), &sph);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_get_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct sk_buff *r_skb;
  	u32 *flags = nlmsg_data(nlh);
  	u32 sportid = NETLINK_CB(skb).portid;
  	u32 seq = nlh->nlmsg_seq;
  
  	r_skb = nlmsg_new(xfrm_spdinfo_msgsize(), GFP_ATOMIC);
  	if (r_skb == NULL)
  		return -ENOMEM;
  
  	if (build_spdinfo(r_skb, net, sportid, seq, *flags) < 0)
  		BUG();
  
  	return nlmsg_unicast(net->xfrm.nlsk, r_skb, sportid);
  }
  
  static inline size_t xfrm_sadinfo_msgsize(void)
  {
  	return NLMSG_ALIGN(4)
  	       + nla_total_size(sizeof(struct xfrmu_sadhinfo))
  	       + nla_total_size(4); /* XFRMA_SAD_CNT */
  }
  
  static int build_sadinfo(struct sk_buff *skb, struct net *net,
  			 u32 portid, u32 seq, u32 flags)
  {
  	struct xfrmk_sadinfo si;
  	struct xfrmu_sadhinfo sh;
  	struct nlmsghdr *nlh;
  	int err;
  	u32 *f;
  
  	nlh = nlmsg_put(skb, portid, seq, XFRM_MSG_NEWSADINFO, sizeof(u32), 0);
  	if (nlh == NULL) /* shouldn't really happen ... */
  		return -EMSGSIZE;
  
  	f = nlmsg_data(nlh);
  	*f = flags;
  	xfrm_sad_getinfo(net, &si);
  
  	sh.sadhmcnt = si.sadhmcnt;
  	sh.sadhcnt = si.sadhcnt;
  
  	err = nla_put_u32(skb, XFRMA_SAD_CNT, si.sadcnt);
  	if (!err)
  		err = nla_put(skb, XFRMA_SAD_HINFO, sizeof(sh), &sh);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_get_sadinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct sk_buff *r_skb;
  	u32 *flags = nlmsg_data(nlh);
  	u32 sportid = NETLINK_CB(skb).portid;
  	u32 seq = nlh->nlmsg_seq;
  
  	r_skb = nlmsg_new(xfrm_sadinfo_msgsize(), GFP_ATOMIC);
  	if (r_skb == NULL)
  		return -ENOMEM;
  
  	if (build_sadinfo(r_skb, net, sportid, seq, *flags) < 0)
  		BUG();
  
  	return nlmsg_unicast(net->xfrm.nlsk, r_skb, sportid);
  }
  
  static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_usersa_id *p = nlmsg_data(nlh);
  	struct xfrm_state *x;
  	struct sk_buff *resp_skb;
  	int err = -ESRCH;
  
  	x = xfrm_user_state_lookup(net, p, attrs, &err);
  	if (x == NULL)
  		goto out_noput;
  
  	resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
  	if (IS_ERR(resp_skb)) {
  		err = PTR_ERR(resp_skb);
  	} else {
  		err = nlmsg_unicast(net->xfrm.nlsk, resp_skb, NETLINK_CB(skb).portid);
  	}
  	xfrm_state_put(x);
  out_noput:
  	return err;
  }
  
  static int verify_userspi_info(struct xfrm_userspi_info *p)
  {
  	switch (p->info.id.proto) {
  	case IPPROTO_AH:
  	case IPPROTO_ESP:
  		break;
  
  	case IPPROTO_COMP:
  		/* IPCOMP spi is 16-bits. */
  		if (p->max >= 0x10000)
  			return -EINVAL;
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	if (p->min > p->max)
  		return -EINVAL;
  
  	return 0;
  }
  
  static int xfrm_alloc_userspi(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state *x;
  	struct xfrm_userspi_info *p;
  	struct sk_buff *resp_skb;
  	xfrm_address_t *daddr;
  	int family;
  	int err;
  	u32 mark;
  	struct xfrm_mark m;
  
  	p = nlmsg_data(nlh);
  	err = verify_userspi_info(p);
  	if (err)
  		goto out_noput;
  
  	family = p->info.family;
  	daddr = &p->info.id.daddr;
  
  	x = NULL;
  
  	mark = xfrm_mark_get(attrs, &m);
  	if (p->info.seq) {
  		x = xfrm_find_acq_byseq(net, mark, p->info.seq);
  		if (x && !xfrm_addr_equal(&x->id.daddr, daddr, family)) {
  			xfrm_state_put(x);
  			x = NULL;
  		}
  	}
  
  	if (!x)
  		x = xfrm_find_acq(net, &m, p->info.mode, p->info.reqid,
  				  p->info.id.proto, daddr,
  				  &p->info.saddr, 1,
  				  family);
  	err = -ENOENT;
  	if (x == NULL)
  		goto out_noput;
  
  	err = xfrm_alloc_spi(x, p->min, p->max);
  	if (err)
  		goto out;
  
  	resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
  	if (IS_ERR(resp_skb)) {
  		err = PTR_ERR(resp_skb);
  		goto out;
  	}
  
  	err = nlmsg_unicast(net->xfrm.nlsk, resp_skb, NETLINK_CB(skb).portid);
  
  out:
  	xfrm_state_put(x);
  out_noput:
  	return err;
  }
  
  static int verify_policy_dir(u8 dir)
  {
  	switch (dir) {
  	case XFRM_POLICY_IN:
  	case XFRM_POLICY_OUT:
  	case XFRM_POLICY_FWD:
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	return 0;
  }
  
  static int verify_policy_type(u8 type)
  {
  	switch (type) {
  	case XFRM_POLICY_TYPE_MAIN:
  #ifdef CONFIG_XFRM_SUB_POLICY
  	case XFRM_POLICY_TYPE_SUB:
  #endif
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	return 0;
  }
  
  static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
  {
  	switch (p->share) {
  	case XFRM_SHARE_ANY:
  	case XFRM_SHARE_SESSION:
  	case XFRM_SHARE_USER:
  	case XFRM_SHARE_UNIQUE:
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	switch (p->action) {
  	case XFRM_POLICY_ALLOW:
  	case XFRM_POLICY_BLOCK:
  		break;
  
  	default:
  		return -EINVAL;
  	}
  
  	switch (p->sel.family) {
  	case AF_INET:
  		break;
  
  	case AF_INET6:
  #if IS_ENABLED(CONFIG_IPV6)
  		break;
  #else
  		return  -EAFNOSUPPORT;
  #endif
  
  	default:
  		return -EINVAL;
  	}
  
  	return verify_policy_dir(p->dir);
  }
  
  static int copy_from_user_sec_ctx(struct xfrm_policy *pol, struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_SEC_CTX];
  	struct xfrm_user_sec_ctx *uctx;
  
  	if (!rt)
  		return 0;
  
  	uctx = nla_data(rt);
  	return security_xfrm_policy_alloc(&pol->security, uctx);
  }
  
  static void copy_templates(struct xfrm_policy *xp, struct xfrm_user_tmpl *ut,
  			   int nr)
  {
  	int i;
  
  	xp->xfrm_nr = nr;
  	for (i = 0; i < nr; i++, ut++) {
  		struct xfrm_tmpl *t = &xp->xfrm_vec[i];
  
  		memcpy(&t->id, &ut->id, sizeof(struct xfrm_id));
  		memcpy(&t->saddr, &ut->saddr,
  		       sizeof(xfrm_address_t));
  		t->reqid = ut->reqid;
  		t->mode = ut->mode;
  		t->share = ut->share;
  		t->optional = ut->optional;
  		t->aalgos = ut->aalgos;
  		t->ealgos = ut->ealgos;
  		t->calgos = ut->calgos;
  		/* If all masks are ~0, then we allow all algorithms. */
  		t->allalgs = !~(t->aalgos & t->ealgos & t->calgos);
  		t->encap_family = ut->family;
  	}
  }
  
  static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
  {
  	int i;
  
  	if (nr > XFRM_MAX_DEPTH)
  		return -EINVAL;
  
  	for (i = 0; i < nr; i++) {
  		/* We never validated the ut->family value, so many
  		 * applications simply leave it at zero.  The check was
  		 * never made and ut->family was ignored because all
  		 * templates could be assumed to have the same family as
  		 * the policy itself.  Now that we will have ipv4-in-ipv6
  		 * and ipv6-in-ipv4 tunnels, this is no longer true.
  		 */
  		if (!ut[i].family)
  			ut[i].family = family;
  
  		switch (ut[i].family) {
  		case AF_INET:
  			break;
  #if IS_ENABLED(CONFIG_IPV6)
  		case AF_INET6:
  			break;
  #endif
  		default:
  			return -EINVAL;
  		}
  	}
  
  	return 0;
  }
  
  static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_TMPL];
  
  	if (!rt) {
  		pol->xfrm_nr = 0;
  	} else {
  		struct xfrm_user_tmpl *utmpl = nla_data(rt);
  		int nr = nla_len(rt) / sizeof(*utmpl);
  		int err;
  
  		err = validate_tmpl(nr, utmpl, pol->family);
  		if (err)
  			return err;
  
  		copy_templates(pol, utmpl, nr);
  	}
  	return 0;
  }
  
  static int copy_from_user_policy_type(u8 *tp, struct nlattr **attrs)
  {
  	struct nlattr *rt = attrs[XFRMA_POLICY_TYPE];
  	struct xfrm_userpolicy_type *upt;
  	u8 type = XFRM_POLICY_TYPE_MAIN;
  	int err;
  
  	if (rt) {
  		upt = nla_data(rt);
  		type = upt->type;
  	}
  
  	err = verify_policy_type(type);
  	if (err)
  		return err;
  
  	*tp = type;
  	return 0;
  }
  
  static void copy_from_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p)
  {
  	xp->priority = p->priority;
  	xp->index = p->index;
  	memcpy(&xp->selector, &p->sel, sizeof(xp->selector));
  	memcpy(&xp->lft, &p->lft, sizeof(xp->lft));
  	xp->action = p->action;
  	xp->flags = p->flags;
  	xp->family = p->sel.family;
  	/* XXX xp->share = p->share; */
  }
  
  static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p, int dir)
  {
  	memset(p, 0, sizeof(*p));
  	memcpy(&p->sel, &xp->selector, sizeof(p->sel));
  	memcpy(&p->lft, &xp->lft, sizeof(p->lft));
  	memcpy(&p->curlft, &xp->curlft, sizeof(p->curlft));
  	p->priority = xp->priority;
  	p->index = xp->index;
  	p->sel.family = xp->family;
  	p->dir = dir;
  	p->action = xp->action;
  	p->flags = xp->flags;
  	p->share = XFRM_SHARE_ANY; /* XXX xp->share */
  }
  
  static struct xfrm_policy *xfrm_policy_construct(struct net *net, struct xfrm_userpolicy_info *p, struct nlattr **attrs, int *errp)
  {
  	struct xfrm_policy *xp = xfrm_policy_alloc(net, GFP_KERNEL);
  	int err;
  
  	if (!xp) {
  		*errp = -ENOMEM;
  		return NULL;
  	}
  
  	copy_from_user_policy(xp, p);
  
  	err = copy_from_user_policy_type(&xp->type, attrs);
  	if (err)
  		goto error;
  
  	if (!(err = copy_from_user_tmpl(xp, attrs)))
  		err = copy_from_user_sec_ctx(xp, attrs);
  	if (err)
  		goto error;
  
  	xfrm_mark_get(attrs, &xp->mark);
  
  	return xp;
   error:
  	*errp = err;
  	xp->walk.dead = 1;
  	xfrm_policy_destroy(xp);
  	return NULL;
  }
  
  static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_userpolicy_info *p = nlmsg_data(nlh);
  	struct xfrm_policy *xp;
  	struct km_event c;
  	int err;
  	int excl;
  	kuid_t loginuid = audit_get_loginuid(current);
  	u32 sessionid = audit_get_sessionid(current);
  	u32 sid;
  
  	err = verify_newpolicy_info(p);
  	if (err)
  		return err;
  	err = verify_sec_ctx_len(attrs);
  	if (err)
  		return err;
  
  	xp = xfrm_policy_construct(net, p, attrs, &err);
  	if (!xp)
  		return err;
  
  	/* shouldn't excl be based on nlh flags??
  	 * Aha! this is anti-netlink really i.e  more pfkey derived
  	 * in netlink excl is a flag and you wouldnt need
  	 * a type XFRM_MSG_UPDPOLICY - JHS */
  	excl = nlh->nlmsg_type == XFRM_MSG_NEWPOLICY;
  	err = xfrm_policy_insert(p->dir, xp, excl);
  	security_task_getsecid(current, &sid);
  	xfrm_audit_policy_add(xp, err ? 0 : 1, loginuid, sessionid, sid);
  
  	if (err) {
  		security_xfrm_policy_free(xp->security);
  		kfree(xp);
  		return err;
  	}
  
  	c.event = nlh->nlmsg_type;
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	km_policy_notify(xp, p->dir, &c);
  
  	xfrm_pol_put(xp);
  
  	return 0;
  }
  
  static int copy_to_user_tmpl(struct xfrm_policy *xp, struct sk_buff *skb)
  {
  	struct xfrm_user_tmpl vec[XFRM_MAX_DEPTH];
  	int i;
  
  	if (xp->xfrm_nr == 0)
  		return 0;
  
  	for (i = 0; i < xp->xfrm_nr; i++) {
  		struct xfrm_user_tmpl *up = &vec[i];
  		struct xfrm_tmpl *kp = &xp->xfrm_vec[i];
  
  		memset(up, 0, sizeof(*up));
  		memcpy(&up->id, &kp->id, sizeof(up->id));
  		up->family = kp->encap_family;
  		memcpy(&up->saddr, &kp->saddr, sizeof(up->saddr));
  		up->reqid = kp->reqid;
  		up->mode = kp->mode;
  		up->share = kp->share;
  		up->optional = kp->optional;
  		up->aalgos = kp->aalgos;
  		up->ealgos = kp->ealgos;
  		up->calgos = kp->calgos;
  	}
  
  	return nla_put(skb, XFRMA_TMPL,
  		       sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr, vec);
  }
  
  static inline int copy_to_user_state_sec_ctx(struct xfrm_state *x, struct sk_buff *skb)
  {
  	if (x->security) {
  		return copy_sec_ctx(x->security, skb);
  	}
  	return 0;
  }
  
  static inline int copy_to_user_sec_ctx(struct xfrm_policy *xp, struct sk_buff *skb)
  {
  	if (xp->security)
  		return copy_sec_ctx(xp->security, skb);
  	return 0;
  }
  static inline size_t userpolicy_type_attrsize(void)
  {
  #ifdef CONFIG_XFRM_SUB_POLICY
  	return nla_total_size(sizeof(struct xfrm_userpolicy_type));
  #else
  	return 0;
  #endif
  }
  
  #ifdef CONFIG_XFRM_SUB_POLICY
  static int copy_to_user_policy_type(u8 type, struct sk_buff *skb)
  {
  	struct xfrm_userpolicy_type upt = {
  		.type = type,
  	};
  
  	return nla_put(skb, XFRMA_POLICY_TYPE, sizeof(upt), &upt);
  }
  
  #else
  static inline int copy_to_user_policy_type(u8 type, struct sk_buff *skb)
  {
  	return 0;
  }
  #endif
  
  static int dump_one_policy(struct xfrm_policy *xp, int dir, int count, void *ptr)
  {
  	struct xfrm_dump_info *sp = ptr;
  	struct xfrm_userpolicy_info *p;
  	struct sk_buff *in_skb = sp->in_skb;
  	struct sk_buff *skb = sp->out_skb;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, sp->nlmsg_seq,
  			XFRM_MSG_NEWPOLICY, sizeof(*p), sp->nlmsg_flags);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	p = nlmsg_data(nlh);
  	copy_to_user_policy(xp, p, dir);
  	err = copy_to_user_tmpl(xp, skb);
  	if (!err)
  		err = copy_to_user_sec_ctx(xp, skb);
  	if (!err)
  		err = copy_to_user_policy_type(xp->type, skb);
  	if (!err)
  		err = xfrm_mark_put(skb, &xp->mark);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  	nlmsg_end(skb, nlh);
  	return 0;
  }
  
  static int xfrm_dump_policy_done(struct netlink_callback *cb)
  {
  	struct xfrm_policy_walk *walk = (struct xfrm_policy_walk *) &cb->args[1];
  
  	xfrm_policy_walk_done(walk);
  	return 0;
  }
  
  static int xfrm_dump_policy(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_policy_walk *walk = (struct xfrm_policy_walk *) &cb->args[1];
  	struct xfrm_dump_info info;
  
  	BUILD_BUG_ON(sizeof(struct xfrm_policy_walk) >
  		     sizeof(cb->args) - sizeof(cb->args[0]));
  
  	info.in_skb = cb->skb;
  	info.out_skb = skb;
  	info.nlmsg_seq = cb->nlh->nlmsg_seq;
  	info.nlmsg_flags = NLM_F_MULTI;
  
  	if (!cb->args[0]) {
  		cb->args[0] = 1;
  		xfrm_policy_walk_init(walk, XFRM_POLICY_TYPE_ANY);
  	}
  
  	(void) xfrm_policy_walk(net, walk, dump_one_policy, &info);
  
  	return skb->len;
  }
  
  static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
  					  struct xfrm_policy *xp,
  					  int dir, u32 seq)
  {
  	struct xfrm_dump_info info;
  	struct sk_buff *skb;
  	int err;
  
  	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  	if (!skb)
  		return ERR_PTR(-ENOMEM);
  
  	info.in_skb = in_skb;
  	info.out_skb = skb;
  	info.nlmsg_seq = seq;
  	info.nlmsg_flags = 0;
  
  	err = dump_one_policy(xp, dir, 0, &info);
  	if (err) {
  		kfree_skb(skb);
  		return ERR_PTR(err);
  	}
  
  	return skb;
  }
  
  static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_policy *xp;
  	struct xfrm_userpolicy_id *p;
  	u8 type = XFRM_POLICY_TYPE_MAIN;
  	int err;
  	struct km_event c;
  	int delete;
  	struct xfrm_mark m;
  	u32 mark = xfrm_mark_get(attrs, &m);
  
  	p = nlmsg_data(nlh);
  	delete = nlh->nlmsg_type == XFRM_MSG_DELPOLICY;
  
  	err = copy_from_user_policy_type(&type, attrs);
  	if (err)
  		return err;
  
  	err = verify_policy_dir(p->dir);
  	if (err)
  		return err;
  
  	if (p->index)
  		xp = xfrm_policy_byid(net, mark, type, p->dir, p->index, delete, &err);
  	else {
  		struct nlattr *rt = attrs[XFRMA_SEC_CTX];
  		struct xfrm_sec_ctx *ctx;
  
  		err = verify_sec_ctx_len(attrs);
  		if (err)
  			return err;
  
  		ctx = NULL;
  		if (rt) {
  			struct xfrm_user_sec_ctx *uctx = nla_data(rt);
  
  			err = security_xfrm_policy_alloc(&ctx, uctx);
  			if (err)
  				return err;
  		}
  		xp = xfrm_policy_bysel_ctx(net, mark, type, p->dir, &p->sel,
  					   ctx, delete, &err);
  		security_xfrm_policy_free(ctx);
  	}
  	if (xp == NULL)
  		return -ENOENT;
  
  	if (!delete) {
  		struct sk_buff *resp_skb;
  
  		resp_skb = xfrm_policy_netlink(skb, xp, p->dir, nlh->nlmsg_seq);
  		if (IS_ERR(resp_skb)) {
  			err = PTR_ERR(resp_skb);
  		} else {
  			err = nlmsg_unicast(net->xfrm.nlsk, resp_skb,
  					    NETLINK_CB(skb).portid);
  		}
  	} else {
  		kuid_t loginuid = audit_get_loginuid(current);
  		u32 sessionid = audit_get_sessionid(current);
  		u32 sid;
  
  		security_task_getsecid(current, &sid);
  		xfrm_audit_policy_delete(xp, err ? 0 : 1, loginuid, sessionid,
  					 sid);
  
  		if (err != 0)
  			goto out;
  
  		c.data.byid = p->index;
  		c.event = nlh->nlmsg_type;
  		c.seq = nlh->nlmsg_seq;
  		c.portid = nlh->nlmsg_pid;
  		km_policy_notify(xp, p->dir, &c);
  	}
  
  out:
  	xfrm_pol_put(xp);
  	if (delete && err == 0)
  		xfrm_garbage_collect(net);
  	return err;
  }
  
  static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct km_event c;
  	struct xfrm_usersa_flush *p = nlmsg_data(nlh);
  	struct xfrm_audit audit_info;
  	int err;
  
  	audit_info.loginuid = audit_get_loginuid(current);
  	audit_info.sessionid = audit_get_sessionid(current);
  	security_task_getsecid(current, &audit_info.secid);
  	err = xfrm_state_flush(net, p->proto, &audit_info);
  	if (err) {
  		if (err == -ESRCH) /* empty table */
  			return 0;
  		return err;
  	}
  	c.data.proto = p->proto;
  	c.event = nlh->nlmsg_type;
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	c.net = net;
  	km_state_notify(NULL, &c);
  
  	return 0;
  }
  
  static inline size_t xfrm_aevent_msgsize(struct xfrm_state *x)
  {
  	size_t replay_size = x->replay_esn ?
  			      xfrm_replay_state_esn_len(x->replay_esn) :
  			      sizeof(struct xfrm_replay_state);
  
  	return NLMSG_ALIGN(sizeof(struct xfrm_aevent_id))
  	       + nla_total_size(replay_size)
  	       + nla_total_size(sizeof(struct xfrm_lifetime_cur))
  	       + nla_total_size(sizeof(struct xfrm_mark))
  	       + nla_total_size(4) /* XFRM_AE_RTHR */
  	       + nla_total_size(4); /* XFRM_AE_ETHR */
  }
  
  static int build_aevent(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c)
  {
  	struct xfrm_aevent_id *id;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, c->portid, c->seq, XFRM_MSG_NEWAE, sizeof(*id), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	id = nlmsg_data(nlh);
  	memcpy(&id->sa_id.daddr, &x->id.daddr,sizeof(x->id.daddr));
  	id->sa_id.spi = x->id.spi;
  	id->sa_id.family = x->props.family;
  	id->sa_id.proto = x->id.proto;
  	memcpy(&id->saddr, &x->props.saddr,sizeof(x->props.saddr));
  	id->reqid = x->props.reqid;
  	id->flags = c->data.aevent;
  
  	if (x->replay_esn) {
  		err = nla_put(skb, XFRMA_REPLAY_ESN_VAL,
  			      xfrm_replay_state_esn_len(x->replay_esn),
  			      x->replay_esn);
  	} else {
  		err = nla_put(skb, XFRMA_REPLAY_VAL, sizeof(x->replay),
  			      &x->replay);
  	}
  	if (err)
  		goto out_cancel;
  	err = nla_put(skb, XFRMA_LTIME_VAL, sizeof(x->curlft), &x->curlft);
  	if (err)
  		goto out_cancel;
  
  	if (id->flags & XFRM_AE_RTHR) {
  		err = nla_put_u32(skb, XFRMA_REPLAY_THRESH, x->replay_maxdiff);
  		if (err)
  			goto out_cancel;
  	}
  	if (id->flags & XFRM_AE_ETHR) {
  		err = nla_put_u32(skb, XFRMA_ETIMER_THRESH,
  				  x->replay_maxage * 10 / HZ);
  		if (err)
  			goto out_cancel;
  	}
  	err = xfrm_mark_put(skb, &x->mark);
  	if (err)
  		goto out_cancel;
  
  	return nlmsg_end(skb, nlh);
  
  out_cancel:
  	nlmsg_cancel(skb, nlh);
  	return err;
  }
  
  static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state *x;
  	struct sk_buff *r_skb;
  	int err;
  	struct km_event c;
  	u32 mark;
  	struct xfrm_mark m;
  	struct xfrm_aevent_id *p = nlmsg_data(nlh);
  	struct xfrm_usersa_id *id = &p->sa_id;
  
  	mark = xfrm_mark_get(attrs, &m);
  
  	x = xfrm_state_lookup(net, mark, &id->daddr, id->spi, id->proto, id->family);
  	if (x == NULL)
  		return -ESRCH;
  
  	r_skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC);
  	if (r_skb == NULL) {
  		xfrm_state_put(x);
  		return -ENOMEM;
  	}
  
  	/*
  	 * XXX: is this lock really needed - none of the other
  	 * gets lock (the concern is things getting updated
  	 * while we are still reading) - jhs
  	*/
  	spin_lock_bh(&x->lock);
  	c.data.aevent = p->flags;
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  
  	if (build_aevent(r_skb, x, &c) < 0)
  		BUG();
  	err = nlmsg_unicast(net->xfrm.nlsk, r_skb, NETLINK_CB(skb).portid);
  	spin_unlock_bh(&x->lock);
  	xfrm_state_put(x);
  	return err;
  }
  
  static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state *x;
  	struct km_event c;
  	int err = - EINVAL;
  	u32 mark = 0;
  	struct xfrm_mark m;
  	struct xfrm_aevent_id *p = nlmsg_data(nlh);
  	struct nlattr *rp = attrs[XFRMA_REPLAY_VAL];
  	struct nlattr *re = attrs[XFRMA_REPLAY_ESN_VAL];
  	struct nlattr *lt = attrs[XFRMA_LTIME_VAL];
  
  	if (!lt && !rp && !re)
  		return err;
  
  	/* pedantic mode - thou shalt sayeth replaceth */
  	if (!(nlh->nlmsg_flags&NLM_F_REPLACE))
  		return err;
  
  	mark = xfrm_mark_get(attrs, &m);
  
  	x = xfrm_state_lookup(net, mark, &p->sa_id.daddr, p->sa_id.spi, p->sa_id.proto, p->sa_id.family);
  	if (x == NULL)
  		return -ESRCH;
  
  	if (x->km.state != XFRM_STATE_VALID)
  		goto out;
  
  	err = xfrm_replay_verify_len(x->replay_esn, re);
  	if (err)
  		goto out;
  
  	spin_lock_bh(&x->lock);
  	xfrm_update_ae_params(x, attrs, 1);
  	spin_unlock_bh(&x->lock);
  
  	c.event = nlh->nlmsg_type;
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	c.data.aevent = XFRM_AE_CU;
  	km_state_notify(x, &c);
  	err = 0;
  out:
  	xfrm_state_put(x);
  	return err;
  }
  
  static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct km_event c;
  	u8 type = XFRM_POLICY_TYPE_MAIN;
  	int err;
  	struct xfrm_audit audit_info;
  
  	err = copy_from_user_policy_type(&type, attrs);
  	if (err)
  		return err;
  
  	audit_info.loginuid = audit_get_loginuid(current);
  	audit_info.sessionid = audit_get_sessionid(current);
  	security_task_getsecid(current, &audit_info.secid);
  	err = xfrm_policy_flush(net, type, &audit_info);
  	if (err) {
  		if (err == -ESRCH) /* empty table */
  			return 0;
  		return err;
  	}
  
  	c.data.type = type;
  	c.event = nlh->nlmsg_type;
  	c.seq = nlh->nlmsg_seq;
  	c.portid = nlh->nlmsg_pid;
  	c.net = net;
  	km_policy_notify(NULL, 0, &c);
  	return 0;
  }
  
  static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_policy *xp;
  	struct xfrm_user_polexpire *up = nlmsg_data(nlh);
  	struct xfrm_userpolicy_info *p = &up->pol;
  	u8 type = XFRM_POLICY_TYPE_MAIN;
  	int err = -ENOENT;
  	struct xfrm_mark m;
  	u32 mark = xfrm_mark_get(attrs, &m);
  
  	err = copy_from_user_policy_type(&type, attrs);
  	if (err)
  		return err;
  
  	err = verify_policy_dir(p->dir);
  	if (err)
  		return err;
  
  	if (p->index)
  		xp = xfrm_policy_byid(net, mark, type, p->dir, p->index, 0, &err);
  	else {
  		struct nlattr *rt = attrs[XFRMA_SEC_CTX];
  		struct xfrm_sec_ctx *ctx;
  
  		err = verify_sec_ctx_len(attrs);
  		if (err)
  			return err;
  
  		ctx = NULL;
  		if (rt) {
  			struct xfrm_user_sec_ctx *uctx = nla_data(rt);
  
  			err = security_xfrm_policy_alloc(&ctx, uctx);
  			if (err)
  				return err;
  		}
  		xp = xfrm_policy_bysel_ctx(net, mark, type, p->dir,
  					   &p->sel, ctx, 0, &err);
  		security_xfrm_policy_free(ctx);
  	}
  	if (xp == NULL)
  		return -ENOENT;
  
  	if (unlikely(xp->walk.dead))
  		goto out;
  
  	err = 0;
  	if (up->hard) {
  		kuid_t loginuid = audit_get_loginuid(current);
  		u32 sessionid = audit_get_sessionid(current);
  		u32 sid;
  
  		security_task_getsecid(current, &sid);
  		xfrm_policy_delete(xp, p->dir);
  		xfrm_audit_policy_delete(xp, 1, loginuid, sessionid, sid);
  
  	} else {
  		// reset the timers here?
  		WARN(1, "Dont know what to do with soft policy expire\n");
  	}
  	km_policy_expired(xp, p->dir, up->hard, nlh->nlmsg_pid);
  
  out:
  	xfrm_pol_put(xp);
  	return err;
  }
  
  static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_state *x;
  	int err;
  	struct xfrm_user_expire *ue = nlmsg_data(nlh);
  	struct xfrm_usersa_info *p = &ue->state;
  	struct xfrm_mark m;
  	u32 mark = xfrm_mark_get(attrs, &m);
  
  	x = xfrm_state_lookup(net, mark, &p->id.daddr, p->id.spi, p->id.proto, p->family);
  
  	err = -ENOENT;
  	if (x == NULL)
  		return err;
  
  	spin_lock_bh(&x->lock);
  	err = -EINVAL;
  	if (x->km.state != XFRM_STATE_VALID)
  		goto out;
  	km_state_expired(x, ue->hard, nlh->nlmsg_pid);
  
  	if (ue->hard) {
  		kuid_t loginuid = audit_get_loginuid(current);
  		u32 sessionid = audit_get_sessionid(current);
  		u32 sid;
  
  		security_task_getsecid(current, &sid);
  		__xfrm_state_delete(x);
  		xfrm_audit_state_delete(x, 1, loginuid, sessionid, sid);
  	}
  	err = 0;
  out:
  	spin_unlock_bh(&x->lock);
  	xfrm_state_put(x);
  	return err;
  }
  
  static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
  		struct nlattr **attrs)
  {
  	struct net *net = sock_net(skb->sk);
  	struct xfrm_policy *xp;
  	struct xfrm_user_tmpl *ut;
  	int i;
  	struct nlattr *rt = attrs[XFRMA_TMPL];
  	struct xfrm_mark mark;
  
  	struct xfrm_user_acquire *ua = nlmsg_data(nlh);
  	struct xfrm_state *x = xfrm_state_alloc(net);
  	int err = -ENOMEM;
  
  	if (!x)
  		goto nomem;
  
  	xfrm_mark_get(attrs, &mark);
  
  	err = verify_newpolicy_info(&ua->policy);
  	if (err)
  		goto bad_policy;
  
  	/*   build an XP */
  	xp = xfrm_policy_construct(net, &ua->policy, attrs, &err);
  	if (!xp)
  		goto free_state;
  
  	memcpy(&x->id, &ua->id, sizeof(ua->id));
  	memcpy(&x->props.saddr, &ua->saddr, sizeof(ua->saddr));
  	memcpy(&x->sel, &ua->sel, sizeof(ua->sel));
  	xp->mark.m = x->mark.m = mark.m;
  	xp->mark.v = x->mark.v = mark.v;
  	ut = nla_data(rt);
  	/* extract the templates and for each call km_key */
  	for (i = 0; i < xp->xfrm_nr; i++, ut++) {
  		struct xfrm_tmpl *t = &xp->xfrm_vec[i];
  		memcpy(&x->id, &t->id, sizeof(x->id));
  		x->props.mode = t->mode;
  		x->props.reqid = t->reqid;
  		x->props.family = ut->family;
  		t->aalgos = ua->aalgos;
  		t->ealgos = ua->ealgos;
  		t->calgos = ua->calgos;
  		err = km_query(x, t, xp);
  
  	}
  
  	kfree(x);
  	kfree(xp);
  
  	return 0;
  
  bad_policy:
  	WARN(1, "BAD policy passed\n");
  free_state:
  	kfree(x);
  nomem:
  	return err;
  }
  
  #ifdef CONFIG_XFRM_MIGRATE
  static int copy_from_user_migrate(struct xfrm_migrate *ma,
  				  struct xfrm_kmaddress *k,
  				  struct nlattr **attrs, int *num)
  {
  	struct nlattr *rt = attrs[XFRMA_MIGRATE];
  	struct xfrm_user_migrate *um;
  	int i, num_migrate;
  
  	if (k != NULL) {
  		struct xfrm_user_kmaddress *uk;
  
  		uk = nla_data(attrs[XFRMA_KMADDRESS]);
  		memcpy(&k->local, &uk->local, sizeof(k->local));
  		memcpy(&k->remote, &uk->remote, sizeof(k->remote));
  		k->family = uk->family;
  		k->reserved = uk->reserved;
  	}
  
  	um = nla_data(rt);
  	num_migrate = nla_len(rt) / sizeof(*um);
  
  	if (num_migrate <= 0 || num_migrate > XFRM_MAX_DEPTH)
  		return -EINVAL;
  
  	for (i = 0; i < num_migrate; i++, um++, ma++) {
  		memcpy(&ma->old_daddr, &um->old_daddr, sizeof(ma->old_daddr));
  		memcpy(&ma->old_saddr, &um->old_saddr, sizeof(ma->old_saddr));
  		memcpy(&ma->new_daddr, &um->new_daddr, sizeof(ma->new_daddr));
  		memcpy(&ma->new_saddr, &um->new_saddr, sizeof(ma->new_saddr));
  
  		ma->proto = um->proto;
  		ma->mode = um->mode;
  		ma->reqid = um->reqid;
  
  		ma->old_family = um->old_family;
  		ma->new_family = um->new_family;
  	}
  
  	*num = i;
  	return 0;
  }
  
  static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
  			   struct nlattr **attrs)
  {
  	struct xfrm_userpolicy_id *pi = nlmsg_data(nlh);
  	struct xfrm_migrate m[XFRM_MAX_DEPTH];
  	struct xfrm_kmaddress km, *kmp;
  	u8 type;
  	int err;
  	int n = 0;
  
  	if (attrs[XFRMA_MIGRATE] == NULL)
  		return -EINVAL;
  
  	kmp = attrs[XFRMA_KMADDRESS] ? &km : NULL;
  
  	err = copy_from_user_policy_type(&type, attrs);
  	if (err)
  		return err;
  
  	err = copy_from_user_migrate((struct xfrm_migrate *)m, kmp, attrs, &n);
  	if (err)
  		return err;
  
  	if (!n)
  		return 0;
  
  	xfrm_migrate(&pi->sel, pi->dir, type, m, n, kmp);
  
  	return 0;
  }
  #else
  static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
  			   struct nlattr **attrs)
  {
  	return -ENOPROTOOPT;
  }
  #endif
  
  #ifdef CONFIG_XFRM_MIGRATE
  static int copy_to_user_migrate(const struct xfrm_migrate *m, struct sk_buff *skb)
  {
  	struct xfrm_user_migrate um;
  
  	memset(&um, 0, sizeof(um));
  	um.proto = m->proto;
  	um.mode = m->mode;
  	um.reqid = m->reqid;
  	um.old_family = m->old_family;
  	memcpy(&um.old_daddr, &m->old_daddr, sizeof(um.old_daddr));
  	memcpy(&um.old_saddr, &m->old_saddr, sizeof(um.old_saddr));
  	um.new_family = m->new_family;
  	memcpy(&um.new_daddr, &m->new_daddr, sizeof(um.new_daddr));
  	memcpy(&um.new_saddr, &m->new_saddr, sizeof(um.new_saddr));
  
  	return nla_put(skb, XFRMA_MIGRATE, sizeof(um), &um);
  }
  
  static int copy_to_user_kmaddress(const struct xfrm_kmaddress *k, struct sk_buff *skb)
  {
  	struct xfrm_user_kmaddress uk;
  
  	memset(&uk, 0, sizeof(uk));
  	uk.family = k->family;
  	uk.reserved = k->reserved;
  	memcpy(&uk.local, &k->local, sizeof(uk.local));
  	memcpy(&uk.remote, &k->remote, sizeof(uk.remote));
  
  	return nla_put(skb, XFRMA_KMADDRESS, sizeof(uk), &uk);
  }
  
  static inline size_t xfrm_migrate_msgsize(int num_migrate, int with_kma)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_userpolicy_id))
  	      + (with_kma ? nla_total_size(sizeof(struct xfrm_kmaddress)) : 0)
  	      + nla_total_size(sizeof(struct xfrm_user_migrate) * num_migrate)
  	      + userpolicy_type_attrsize();
  }
  
  static int build_migrate(struct sk_buff *skb, const struct xfrm_migrate *m,
  			 int num_migrate, const struct xfrm_kmaddress *k,
  			 const struct xfrm_selector *sel, u8 dir, u8 type)
  {
  	const struct xfrm_migrate *mp;
  	struct xfrm_userpolicy_id *pol_id;
  	struct nlmsghdr *nlh;
  	int i, err;
  
  	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_MIGRATE, sizeof(*pol_id), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	pol_id = nlmsg_data(nlh);
  	/* copy data from selector, dir, and type to the pol_id */
  	memset(pol_id, 0, sizeof(*pol_id));
  	memcpy(&pol_id->sel, sel, sizeof(pol_id->sel));
  	pol_id->dir = dir;
  
  	if (k != NULL) {
  		err = copy_to_user_kmaddress(k, skb);
  		if (err)
  			goto out_cancel;
  	}
  	err = copy_to_user_policy_type(type, skb);
  	if (err)
  		goto out_cancel;
  	for (i = 0, mp = m ; i < num_migrate; i++, mp++) {
  		err = copy_to_user_migrate(mp, skb);
  		if (err)
  			goto out_cancel;
  	}
  
  	return nlmsg_end(skb, nlh);
  
  out_cancel:
  	nlmsg_cancel(skb, nlh);
  	return err;
  }
  
  static int xfrm_send_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
  			     const struct xfrm_migrate *m, int num_migrate,
  			     const struct xfrm_kmaddress *k)
  {
  	struct net *net = &init_net;
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_migrate_msgsize(num_migrate, !!k), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	/* build migrate */
  	if (build_migrate(skb, m, num_migrate, k, sel, dir, type) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_MIGRATE, GFP_ATOMIC);
  }
  #else
  static int xfrm_send_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
  			     const struct xfrm_migrate *m, int num_migrate,
  			     const struct xfrm_kmaddress *k)
  {
  	return -ENOPROTOOPT;
  }
  #endif
  
  #define XMSGSIZE(type) sizeof(struct type)
  
  static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
  	[XFRM_MSG_NEWSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_info),
  	[XFRM_MSG_DELSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_id),
  	[XFRM_MSG_GETSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_id),
  	[XFRM_MSG_NEWPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_info),
  	[XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
  	[XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
  	[XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userspi_info),
  	[XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_acquire),
  	[XFRM_MSG_EXPIRE      - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_expire),
  	[XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_info),
  	[XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_info),
  	[XFRM_MSG_POLEXPIRE   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_polexpire),
  	[XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_flush),
  	[XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = 0,
  	[XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
  	[XFRM_MSG_GETAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
  	[XFRM_MSG_REPORT      - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_report),
  	[XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
  	[XFRM_MSG_GETSADINFO  - XFRM_MSG_BASE] = sizeof(u32),
  	[XFRM_MSG_GETSPDINFO  - XFRM_MSG_BASE] = sizeof(u32),
  };
  
  #undef XMSGSIZE
  
  static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
  	[XFRMA_SA]		= { .len = sizeof(struct xfrm_usersa_info)},
  	[XFRMA_POLICY]		= { .len = sizeof(struct xfrm_userpolicy_info)},
  	[XFRMA_LASTUSED]	= { .type = NLA_U64},
  	[XFRMA_ALG_AUTH_TRUNC]	= { .len = sizeof(struct xfrm_algo_auth)},
  	[XFRMA_ALG_AEAD]	= { .len = sizeof(struct xfrm_algo_aead) },
  	[XFRMA_ALG_AUTH]	= { .len = sizeof(struct xfrm_algo) },
  	[XFRMA_ALG_CRYPT]	= { .len = sizeof(struct xfrm_algo) },
  	[XFRMA_ALG_COMP]	= { .len = sizeof(struct xfrm_algo) },
  	[XFRMA_ENCAP]		= { .len = sizeof(struct xfrm_encap_tmpl) },
  	[XFRMA_TMPL]		= { .len = sizeof(struct xfrm_user_tmpl) },
  	[XFRMA_SEC_CTX]		= { .len = sizeof(struct xfrm_sec_ctx) },
  	[XFRMA_LTIME_VAL]	= { .len = sizeof(struct xfrm_lifetime_cur) },
  	[XFRMA_REPLAY_VAL]	= { .len = sizeof(struct xfrm_replay_state) },
  	[XFRMA_REPLAY_THRESH]	= { .type = NLA_U32 },
  	[XFRMA_ETIMER_THRESH]	= { .type = NLA_U32 },
  	[XFRMA_SRCADDR]		= { .len = sizeof(xfrm_address_t) },
  	[XFRMA_COADDR]		= { .len = sizeof(xfrm_address_t) },
  	[XFRMA_POLICY_TYPE]	= { .len = sizeof(struct xfrm_userpolicy_type)},
  	[XFRMA_MIGRATE]		= { .len = sizeof(struct xfrm_user_migrate) },
  	[XFRMA_KMADDRESS]	= { .len = sizeof(struct xfrm_user_kmaddress) },
  	[XFRMA_MARK]		= { .len = sizeof(struct xfrm_mark) },
  	[XFRMA_TFCPAD]		= { .type = NLA_U32 },
  	[XFRMA_REPLAY_ESN_VAL]	= { .len = sizeof(struct xfrm_replay_state_esn) },
  	[XFRMA_SA_EXTRA_FLAGS]	= { .type = NLA_U32 },
  };
  
  static const struct xfrm_link {
  	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
  	int (*dump)(struct sk_buff *, struct netlink_callback *);
  	int (*done)(struct netlink_callback *);
  } xfrm_dispatch[XFRM_NR_MSGTYPES] = {
  	[XFRM_MSG_NEWSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
  	[XFRM_MSG_DELSA       - XFRM_MSG_BASE] = { .doit = xfrm_del_sa        },
  	[XFRM_MSG_GETSA       - XFRM_MSG_BASE] = { .doit = xfrm_get_sa,
  						   .dump = xfrm_dump_sa,
  						   .done = xfrm_dump_sa_done  },
  	[XFRM_MSG_NEWPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
  	[XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy    },
  	[XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy,
  						   .dump = xfrm_dump_policy,
  						   .done = xfrm_dump_policy_done },
  	[XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = { .doit = xfrm_alloc_userspi },
  	[XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = { .doit = xfrm_add_acquire   },
  	[XFRM_MSG_EXPIRE      - XFRM_MSG_BASE] = { .doit = xfrm_add_sa_expire },
  	[XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
  	[XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
  	[XFRM_MSG_POLEXPIRE   - XFRM_MSG_BASE] = { .doit = xfrm_add_pol_expire},
  	[XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = { .doit = xfrm_flush_sa      },
  	[XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = { .doit = xfrm_flush_policy  },
  	[XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = { .doit = xfrm_new_ae  },
  	[XFRM_MSG_GETAE       - XFRM_MSG_BASE] = { .doit = xfrm_get_ae  },
  	[XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = { .doit = xfrm_do_migrate    },
  	[XFRM_MSG_GETSADINFO  - XFRM_MSG_BASE] = { .doit = xfrm_get_sadinfo   },
  	[XFRM_MSG_GETSPDINFO  - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo   },
  };
  
  static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
  {
  	struct net *net = sock_net(skb->sk);
  	struct nlattr *attrs[XFRMA_MAX+1];
  	const struct xfrm_link *link;
  	int type, err;
  
  	type = nlh->nlmsg_type;
  	if (type > XFRM_MSG_MAX)
  		return -EINVAL;
  
  	type -= XFRM_MSG_BASE;
  	link = &xfrm_dispatch[type];
  
  	/* All operations require privileges, even GET */
  	if (!netlink_net_capable(skb, CAP_NET_ADMIN))
  		return -EPERM;
  
  	if ((type == (XFRM_MSG_GETSA - XFRM_MSG_BASE) ||
  	     type == (XFRM_MSG_GETPOLICY - XFRM_MSG_BASE)) &&
  	    (nlh->nlmsg_flags & NLM_F_DUMP)) {
  		if (link->dump == NULL)
  			return -EINVAL;
  
  		{
  			struct netlink_dump_control c = {
  				.dump = link->dump,
  				.done = link->done,
  			};
  			return netlink_dump_start(net->xfrm.nlsk, skb, nlh, &c);
  		}
  	}
  
  	err = nlmsg_parse(nlh, xfrm_msg_min[type], attrs, XFRMA_MAX,
  			  xfrma_policy);
  	if (err < 0)
  		return err;
  
  	if (link->doit == NULL)
  		return -EINVAL;
  
  	return link->doit(skb, nlh, attrs);
  }
  
  static void xfrm_netlink_rcv(struct sk_buff *skb)
  {
  	mutex_lock(&xfrm_cfg_mutex);
  	netlink_rcv_skb(skb, &xfrm_user_rcv_msg);
  	mutex_unlock(&xfrm_cfg_mutex);
  }
  
  static inline size_t xfrm_expire_msgsize(void)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_user_expire))
  	       + nla_total_size(sizeof(struct xfrm_mark));
  }
  
  static int build_expire(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c)
  {
  	struct xfrm_user_expire *ue;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, c->portid, 0, XFRM_MSG_EXPIRE, sizeof(*ue), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	ue = nlmsg_data(nlh);
  	copy_to_user_state(x, &ue->state);
  	ue->hard = (c->data.hard != 0) ? 1 : 0;
  
  	err = xfrm_mark_put(skb, &x->mark);
  	if (err)
  		return err;
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_exp_state_notify(struct xfrm_state *x, const struct km_event *c)
  {
  	struct net *net = xs_net(x);
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_expire_msgsize(), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_expire(skb, x, c) < 0) {
  		kfree_skb(skb);
  		return -EMSGSIZE;
  	}
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_EXPIRE, GFP_ATOMIC);
  }
  
  static int xfrm_aevent_state_notify(struct xfrm_state *x, const struct km_event *c)
  {
  	struct net *net = xs_net(x);
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_aevent(skb, x, c) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_AEVENTS, GFP_ATOMIC);
  }
  
  static int xfrm_notify_sa_flush(const struct km_event *c)
  {
  	struct net *net = c->net;
  	struct xfrm_usersa_flush *p;
  	struct nlmsghdr *nlh;
  	struct sk_buff *skb;
  	int len = NLMSG_ALIGN(sizeof(struct xfrm_usersa_flush));
  
  	skb = nlmsg_new(len, GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	nlh = nlmsg_put(skb, c->portid, c->seq, XFRM_MSG_FLUSHSA, sizeof(*p), 0);
  	if (nlh == NULL) {
  		kfree_skb(skb);
  		return -EMSGSIZE;
  	}
  
  	p = nlmsg_data(nlh);
  	p->proto = c->data.proto;
  
  	nlmsg_end(skb, nlh);
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_SA, GFP_ATOMIC);
  }
  
  static inline size_t xfrm_sa_len(struct xfrm_state *x)
  {
  	size_t l = 0;
  	if (x->aead)
  		l += nla_total_size(aead_len(x->aead));
  	if (x->aalg) {
  		l += nla_total_size(sizeof(struct xfrm_algo) +
  				    (x->aalg->alg_key_len + 7) / 8);
  		l += nla_total_size(xfrm_alg_auth_len(x->aalg));
  	}
  	if (x->ealg)
  		l += nla_total_size(xfrm_alg_len(x->ealg));
  	if (x->calg)
  		l += nla_total_size(sizeof(*x->calg));
  	if (x->encap)
  		l += nla_total_size(sizeof(*x->encap));
  	if (x->tfcpad)
  		l += nla_total_size(sizeof(x->tfcpad));
  	if (x->replay_esn)
  		l += nla_total_size(xfrm_replay_state_esn_len(x->replay_esn));
  	if (x->security)
  		l += nla_total_size(sizeof(struct xfrm_user_sec_ctx) +
  				    x->security->ctx_len);
  	if (x->coaddr)
  		l += nla_total_size(sizeof(*x->coaddr));
  	if (x->props.extra_flags)
  		l += nla_total_size(sizeof(x->props.extra_flags));
  
  	/* Must count x->lastused as it may become non-zero behind our back. */
  	l += nla_total_size(sizeof(u64));
  
  	return l;
  }
  
  static int xfrm_notify_sa(struct xfrm_state *x, const struct km_event *c)
  {
  	struct net *net = xs_net(x);
  	struct xfrm_usersa_info *p;
  	struct xfrm_usersa_id *id;
  	struct nlmsghdr *nlh;
  	struct sk_buff *skb;
  	int len = xfrm_sa_len(x);
  	int headlen, err;
  
  	headlen = sizeof(*p);
  	if (c->event == XFRM_MSG_DELSA) {
  		len += nla_total_size(headlen);
  		headlen = sizeof(*id);
  		len += nla_total_size(sizeof(struct xfrm_mark));
  	}
  	len += NLMSG_ALIGN(headlen);
  
  	skb = nlmsg_new(len, GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	nlh = nlmsg_put(skb, c->portid, c->seq, c->event, headlen, 0);
  	err = -EMSGSIZE;
  	if (nlh == NULL)
  		goto out_free_skb;
  
  	p = nlmsg_data(nlh);
  	if (c->event == XFRM_MSG_DELSA) {
  		struct nlattr *attr;
  
  		id = nlmsg_data(nlh);
  		memcpy(&id->daddr, &x->id.daddr, sizeof(id->daddr));
  		id->spi = x->id.spi;
  		id->family = x->props.family;
  		id->proto = x->id.proto;
  
  		attr = nla_reserve(skb, XFRMA_SA, sizeof(*p));
  		err = -EMSGSIZE;
  		if (attr == NULL)
  			goto out_free_skb;
  
  		p = nla_data(attr);
  	}
  	err = copy_to_user_state_extra(x, p, skb);
  	if (err)
  		goto out_free_skb;
  
  	nlmsg_end(skb, nlh);
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_SA, GFP_ATOMIC);
  
  out_free_skb:
  	kfree_skb(skb);
  	return err;
  }
  
  static int xfrm_send_state_notify(struct xfrm_state *x, const struct km_event *c)
  {
  
  	switch (c->event) {
  	case XFRM_MSG_EXPIRE:
  		return xfrm_exp_state_notify(x, c);
  	case XFRM_MSG_NEWAE:
  		return xfrm_aevent_state_notify(x, c);
  	case XFRM_MSG_DELSA:
  	case XFRM_MSG_UPDSA:
  	case XFRM_MSG_NEWSA:
  		return xfrm_notify_sa(x, c);
  	case XFRM_MSG_FLUSHSA:
  		return xfrm_notify_sa_flush(c);
  	default:
  		printk(KERN_NOTICE "xfrm_user: Unknown SA event %d\n",
  		       c->event);
  		break;
  	}
  
  	return 0;
  
  }
  
  static inline size_t xfrm_acquire_msgsize(struct xfrm_state *x,
  					  struct xfrm_policy *xp)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_user_acquire))
  	       + nla_total_size(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr)
  	       + nla_total_size(sizeof(struct xfrm_mark))
  	       + nla_total_size(xfrm_user_sec_ctx_size(x->security))
  	       + userpolicy_type_attrsize();
  }
  
  static int build_acquire(struct sk_buff *skb, struct xfrm_state *x,
  			 struct xfrm_tmpl *xt, struct xfrm_policy *xp)
  {
  	__u32 seq = xfrm_get_acqseq();
  	struct xfrm_user_acquire *ua;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_ACQUIRE, sizeof(*ua), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	ua = nlmsg_data(nlh);
  	memcpy(&ua->id, &x->id, sizeof(ua->id));
  	memcpy(&ua->saddr, &x->props.saddr, sizeof(ua->saddr));
  	memcpy(&ua->sel, &x->sel, sizeof(ua->sel));
  	copy_to_user_policy(xp, &ua->policy, XFRM_POLICY_OUT);
  	ua->aalgos = xt->aalgos;
  	ua->ealgos = xt->ealgos;
  	ua->calgos = xt->calgos;
  	ua->seq = x->km.seq = seq;
  
  	err = copy_to_user_tmpl(xp, skb);
  	if (!err)
  		err = copy_to_user_state_sec_ctx(x, skb);
  	if (!err)
  		err = copy_to_user_policy_type(xp->type, skb);
  	if (!err)
  		err = xfrm_mark_put(skb, &xp->mark);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_send_acquire(struct xfrm_state *x, struct xfrm_tmpl *xt,
  			     struct xfrm_policy *xp)
  {
  	struct net *net = xs_net(x);
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_acquire_msgsize(x, xp), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_acquire(skb, x, xt, xp) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_ACQUIRE, GFP_ATOMIC);
  }
  
  /* User gives us xfrm_user_policy_info followed by an array of 0
   * or more templates.
   */
  static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt,
  					       u8 *data, int len, int *dir)
  {
  	struct net *net = sock_net(sk);
  	struct xfrm_userpolicy_info *p = (struct xfrm_userpolicy_info *)data;
  	struct xfrm_user_tmpl *ut = (struct xfrm_user_tmpl *) (p + 1);
  	struct xfrm_policy *xp;
  	int nr;
  
  	switch (sk->sk_family) {
  	case AF_INET:
  		if (opt != IP_XFRM_POLICY) {
  			*dir = -EOPNOTSUPP;
  			return NULL;
  		}
  		break;
  #if IS_ENABLED(CONFIG_IPV6)
  	case AF_INET6:
  		if (opt != IPV6_XFRM_POLICY) {
  			*dir = -EOPNOTSUPP;
  			return NULL;
  		}
  		break;
  #endif
  	default:
  		*dir = -EINVAL;
  		return NULL;
  	}
  
  	*dir = -EINVAL;
  
  	if (len < sizeof(*p) ||
  	    verify_newpolicy_info(p))
  		return NULL;
  
  	nr = ((len - sizeof(*p)) / sizeof(*ut));
  	if (validate_tmpl(nr, ut, p->sel.family))
  		return NULL;
  
  	if (p->dir > XFRM_POLICY_OUT)
  		return NULL;
  
  	xp = xfrm_policy_alloc(net, GFP_ATOMIC);
  	if (xp == NULL) {
  		*dir = -ENOBUFS;
  		return NULL;
  	}
  
  	copy_from_user_policy(xp, p);
  	xp->type = XFRM_POLICY_TYPE_MAIN;
  	copy_templates(xp, ut, nr);
  
  	*dir = p->dir;
  
  	return xp;
  }
  
  static inline size_t xfrm_polexpire_msgsize(struct xfrm_policy *xp)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_user_polexpire))
  	       + nla_total_size(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr)
  	       + nla_total_size(xfrm_user_sec_ctx_size(xp->security))
  	       + nla_total_size(sizeof(struct xfrm_mark))
  	       + userpolicy_type_attrsize();
  }
  
  static int build_polexpire(struct sk_buff *skb, struct xfrm_policy *xp,
  			   int dir, const struct km_event *c)
  {
  	struct xfrm_user_polexpire *upe;
  	int hard = c->data.hard;
  	struct nlmsghdr *nlh;
  	int err;
  
  	nlh = nlmsg_put(skb, c->portid, 0, XFRM_MSG_POLEXPIRE, sizeof(*upe), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	upe = nlmsg_data(nlh);
  	copy_to_user_policy(xp, &upe->pol, dir);
  	err = copy_to_user_tmpl(xp, skb);
  	if (!err)
  		err = copy_to_user_sec_ctx(xp, skb);
  	if (!err)
  		err = copy_to_user_policy_type(xp->type, skb);
  	if (!err)
  		err = xfrm_mark_put(skb, &xp->mark);
  	if (err) {
  		nlmsg_cancel(skb, nlh);
  		return err;
  	}
  	upe->hard = !!hard;
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_exp_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c)
  {
  	struct net *net = xp_net(xp);
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_polexpire_msgsize(xp), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_polexpire(skb, xp, dir, c) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_EXPIRE, GFP_ATOMIC);
  }
  
  static int xfrm_notify_policy(struct xfrm_policy *xp, int dir, const struct km_event *c)
  {
  	int len = nla_total_size(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr);
  	struct net *net = xp_net(xp);
  	struct xfrm_userpolicy_info *p;
  	struct xfrm_userpolicy_id *id;
  	struct nlmsghdr *nlh;
  	struct sk_buff *skb;
  	int headlen, err;
  
  	headlen = sizeof(*p);
  	if (c->event == XFRM_MSG_DELPOLICY) {
  		len += nla_total_size(headlen);
  		headlen = sizeof(*id);
  	}
  	len += userpolicy_type_attrsize();
  	len += nla_total_size(sizeof(struct xfrm_mark));
  	len += NLMSG_ALIGN(headlen);
  
  	skb = nlmsg_new(len, GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	nlh = nlmsg_put(skb, c->portid, c->seq, c->event, headlen, 0);
  	err = -EMSGSIZE;
  	if (nlh == NULL)
  		goto out_free_skb;
  
  	p = nlmsg_data(nlh);
  	if (c->event == XFRM_MSG_DELPOLICY) {
  		struct nlattr *attr;
  
  		id = nlmsg_data(nlh);
  		memset(id, 0, sizeof(*id));
  		id->dir = dir;
  		if (c->data.byid)
  			id->index = xp->index;
  		else
  			memcpy(&id->sel, &xp->selector, sizeof(id->sel));
  
  		attr = nla_reserve(skb, XFRMA_POLICY, sizeof(*p));
  		err = -EMSGSIZE;
  		if (attr == NULL)
  			goto out_free_skb;
  
  		p = nla_data(attr);
  	}
  
  	copy_to_user_policy(xp, p, dir);
  	err = copy_to_user_tmpl(xp, skb);
  	if (!err)
  		err = copy_to_user_policy_type(xp->type, skb);
  	if (!err)
  		err = xfrm_mark_put(skb, &xp->mark);
  	if (err)
  		goto out_free_skb;
  
  	nlmsg_end(skb, nlh);
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_POLICY, GFP_ATOMIC);
  
  out_free_skb:
  	kfree_skb(skb);
  	return err;
  }
  
  static int xfrm_notify_policy_flush(const struct km_event *c)
  {
  	struct net *net = c->net;
  	struct nlmsghdr *nlh;
  	struct sk_buff *skb;
  	int err;
  
  	skb = nlmsg_new(userpolicy_type_attrsize(), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	nlh = nlmsg_put(skb, c->portid, c->seq, XFRM_MSG_FLUSHPOLICY, 0, 0);
  	err = -EMSGSIZE;
  	if (nlh == NULL)
  		goto out_free_skb;
  	err = copy_to_user_policy_type(c->data.type, skb);
  	if (err)
  		goto out_free_skb;
  
  	nlmsg_end(skb, nlh);
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_POLICY, GFP_ATOMIC);
  
  out_free_skb:
  	kfree_skb(skb);
  	return err;
  }
  
  static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c)
  {
  
  	switch (c->event) {
  	case XFRM_MSG_NEWPOLICY:
  	case XFRM_MSG_UPDPOLICY:
  	case XFRM_MSG_DELPOLICY:
  		return xfrm_notify_policy(xp, dir, c);
  	case XFRM_MSG_FLUSHPOLICY:
  		return xfrm_notify_policy_flush(c);
  	case XFRM_MSG_POLEXPIRE:
  		return xfrm_exp_policy_notify(xp, dir, c);
  	default:
  		printk(KERN_NOTICE "xfrm_user: Unknown Policy event %d\n",
  		       c->event);
  	}
  
  	return 0;
  
  }
  
  static inline size_t xfrm_report_msgsize(void)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_user_report));
  }
  
  static int build_report(struct sk_buff *skb, u8 proto,
  			struct xfrm_selector *sel, xfrm_address_t *addr)
  {
  	struct xfrm_user_report *ur;
  	struct nlmsghdr *nlh;
  
  	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_REPORT, sizeof(*ur), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	ur = nlmsg_data(nlh);
  	ur->proto = proto;
  	memcpy(&ur->sel, sel, sizeof(ur->sel));
  
  	if (addr) {
  		int err = nla_put(skb, XFRMA_COADDR, sizeof(*addr), addr);
  		if (err) {
  			nlmsg_cancel(skb, nlh);
  			return err;
  		}
  	}
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_send_report(struct net *net, u8 proto,
  			    struct xfrm_selector *sel, xfrm_address_t *addr)
  {
  	struct sk_buff *skb;
  
  	skb = nlmsg_new(xfrm_report_msgsize(), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_report(skb, proto, sel, addr) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_REPORT, GFP_ATOMIC);
  }
  
  static inline size_t xfrm_mapping_msgsize(void)
  {
  	return NLMSG_ALIGN(sizeof(struct xfrm_user_mapping));
  }
  
  static int build_mapping(struct sk_buff *skb, struct xfrm_state *x,
  			 xfrm_address_t *new_saddr, __be16 new_sport)
  {
  	struct xfrm_user_mapping *um;
  	struct nlmsghdr *nlh;
  
  	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_MAPPING, sizeof(*um), 0);
  	if (nlh == NULL)
  		return -EMSGSIZE;
  
  	um = nlmsg_data(nlh);
  
  	memcpy(&um->id.daddr, &x->id.daddr, sizeof(um->id.daddr));
  	um->id.spi = x->id.spi;
  	um->id.family = x->props.family;
  	um->id.proto = x->id.proto;
  	memcpy(&um->new_saddr, new_saddr, sizeof(um->new_saddr));
  	memcpy(&um->old_saddr, &x->props.saddr, sizeof(um->old_saddr));
  	um->new_sport = new_sport;
  	um->old_sport = x->encap->encap_sport;
  	um->reqid = x->props.reqid;
  
  	return nlmsg_end(skb, nlh);
  }
  
  static int xfrm_send_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr,
  			     __be16 sport)
  {
  	struct net *net = xs_net(x);
  	struct sk_buff *skb;
  
  	if (x->id.proto != IPPROTO_ESP)
  		return -EINVAL;
  
  	if (!x->encap)
  		return -EINVAL;
  
  	skb = nlmsg_new(xfrm_mapping_msgsize(), GFP_ATOMIC);
  	if (skb == NULL)
  		return -ENOMEM;
  
  	if (build_mapping(skb, x, ipaddr, sport) < 0)
  		BUG();
  
  	return nlmsg_multicast(net->xfrm.nlsk, skb, 0, XFRMNLGRP_MAPPING, GFP_ATOMIC);
  }
  
  static struct xfrm_mgr netlink_mgr = {
  	.id		= "netlink",
  	.notify		= xfrm_send_state_notify,
  	.acquire	= xfrm_send_acquire,
  	.compile_policy	= xfrm_compile_policy,
  	.notify_policy	= xfrm_send_policy_notify,
  	.report		= xfrm_send_report,
  	.migrate	= xfrm_send_migrate,
  	.new_mapping	= xfrm_send_mapping,
  };
  
  static int __net_init xfrm_user_net_init(struct net *net)
  {
  	struct sock *nlsk;
  	struct netlink_kernel_cfg cfg = {
  		.groups	= XFRMNLGRP_MAX,
  		.input	= xfrm_netlink_rcv,
  	};
  
  	nlsk = netlink_kernel_create(net, NETLINK_XFRM, &cfg);
  	if (nlsk == NULL)
  		return -ENOMEM;
  	net->xfrm.nlsk_stash = nlsk; /* Don't set to NULL */
  	rcu_assign_pointer(net->xfrm.nlsk, nlsk);
  	return 0;
  }
  
  static void __net_exit xfrm_user_net_exit(struct list_head *net_exit_list)
  {
  	struct net *net;
  	list_for_each_entry(net, net_exit_list, exit_list)
  		RCU_INIT_POINTER(net->xfrm.nlsk, NULL);
  	synchronize_net();
  	list_for_each_entry(net, net_exit_list, exit_list)
  		netlink_kernel_release(net->xfrm.nlsk_stash);
  }
  
  static struct pernet_operations xfrm_user_net_ops = {
  	.init	    = xfrm_user_net_init,
  	.exit_batch = xfrm_user_net_exit,
  };
  
  static int __init xfrm_user_init(void)
  {
  	int rv;
  
  	printk(KERN_INFO "Initializing XFRM netlink socket\n");
  
  	rv = register_pernet_subsys(&xfrm_user_net_ops);
  	if (rv < 0)
  		return rv;
  	rv = xfrm_register_km(&netlink_mgr);
  	if (rv < 0)
  		unregister_pernet_subsys(&xfrm_user_net_ops);
  	return rv;
  }
  
  static void __exit xfrm_user_exit(void)
  {
  	xfrm_unregister_km(&netlink_mgr);
  	unregister_pernet_subsys(&xfrm_user_net_ops);
  }
  
  module_init(xfrm_user_init);
  module_exit(xfrm_user_exit);
  MODULE_LICENSE("GPL");
  MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_XFRM);
  
  