// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/key/af_key.c     An implementation of PF_KEYv2 sockets.
 *
 * Authors:     Maxim Giryaev   <gem@asplinux.ru>
 *              David S. Miller <davem@redhat.com>
 *              Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 *              Kunihiro Ishiguro <kunihiro@ipinfusion.com>
 *              Kazunori MIYAZAWA / USAGI Project <miyazawa@linux-ipv6.org>
 *              Derek Atkins <derek@ihtfp.com>
 */

#include <linux/capability.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/socket.h>
#include <linux/pfkeyv2.h>
#include <linux/ipsec.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/xfrm.h>

#include <net/sock.h>

#define _X2KEY(x) ((x) == XFRM_INF ? 0 : (x))
#define _KEY2X(x) ((x) == 0 ? XFRM_INF : (x))

static unsigned int pfkey_net_id __read_mostly;
struct netns_pfkey {
        /* List of all pfkey sockets. */
        struct hlist_head table;
        atomic_t socks_nr;
};
static DEFINE_MUTEX(pfkey_mutex);

#define DUMMY_MARK 0
static const struct xfrm_mark dummy_mark = {0, 0};
struct pfkey_sock {
        /* struct sock must be the first member of struct pfkey_sock */
        struct sock     sk;
        int             registered;
        int             promisc;

        struct {
                uint8_t         msg_version;
                uint32_t        msg_portid;
                int             (*dump)(struct pfkey_sock *sk);
                void            (*done)(struct pfkey_sock *sk);
                union {
                        struct xfrm_policy_walk policy;
                        struct xfrm_state_walk  state;
                } u;
                struct sk_buff  *skb;
        } dump;
        struct mutex dump_lock;
};

static int parse_sockaddr_pair(struct sockaddr *sa, int ext_len,
                               xfrm_address_t *saddr, xfrm_address_t *daddr,
                               u16 *family);

static inline struct pfkey_sock *pfkey_sk(struct sock *sk)
{
        return (struct pfkey_sock *)sk;
}

static int pfkey_can_dump(const struct sock *sk)
{
        if (3 * atomic_read(&sk->sk_rmem_alloc) <= 2 * sk->sk_rcvbuf)
                return 1;
        return 0;
}

static void pfkey_terminate_dump(struct pfkey_sock *pfk)
{
        if (pfk->dump.dump) {
                if (pfk->dump.skb) {
                        kfree_skb(pfk->dump.skb);
                        pfk->dump.skb = NULL;
                }
                pfk->dump.done(pfk);
                pfk->dump.dump = NULL;
                pfk->dump.done = NULL;
        }
}

static void pfkey_sock_destruct(struct sock *sk)
{
        struct net *net = sock_net(sk);
        struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);

        pfkey_terminate_dump(pfkey_sk(sk));
        skb_queue_purge(&sk->sk_receive_queue);

        if (!sock_flag(sk, SOCK_DEAD)) {
                pr_err("Attempt to release alive pfkey socket: %p\n", sk);
                return;
        }

        WARN_ON(atomic_read(&sk->sk_rmem_alloc));
        WARN_ON(refcount_read(&sk->sk_wmem_alloc));

        atomic_dec(&net_pfkey->socks_nr);
}

static const struct proto_ops pfkey_ops;

static void pfkey_insert(struct sock *sk)
{
        struct net *net = sock_net(sk);
        struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);

        mutex_lock(&pfkey_mutex);
        sk_add_node_rcu(sk, &net_pfkey->table);
        mutex_unlock(&pfkey_mutex);
}

static void pfkey_remove(struct sock *sk)
{
        mutex_lock(&pfkey_mutex);
        sk_del_node_init_rcu(sk);
        mutex_unlock(&pfkey_mutex);
}

static struct proto key_proto = {
        .name     = "KEY",
        .owner    = THIS_MODULE,
        .obj_size = sizeof(struct pfkey_sock),
};

static int pfkey_create(struct net *net, struct socket *sock, int protocol,
                        int kern)
{
        struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);
        struct sock *sk;
        struct pfkey_sock *pfk;
        int err;

        if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
                return -EPERM;
        if (sock->type != SOCK_RAW)
                return -ESOCKTNOSUPPORT;
        if (protocol != PF_KEY_V2)
                return -EPROTONOSUPPORT;

        err = -ENOMEM;
        sk = sk_alloc(net, PF_KEY, GFP_KERNEL, &key_proto, kern);
        if (sk == NULL)
                goto out;

        pfk = pfkey_sk(sk);
        mutex_init(&pfk->dump_lock);

        sock->ops = &pfkey_ops;
        sock_init_data(sock, sk);

        sk->sk_family = PF_KEY;
        sk->sk_destruct = pfkey_sock_destruct;

        atomic_inc(&net_pfkey->socks_nr);

        pfkey_insert(sk);

        return 0;
out:
        return err;
}

static int pfkey_release(struct socket *sock)
{
        struct sock *sk = sock->sk;

        if (!sk)
                return 0;

        pfkey_remove(sk);

        sock_orphan(sk);
        sock->sk = NULL;
        skb_queue_purge(&sk->sk_write_queue);

        synchronize_rcu();
        sock_put(sk);

        return 0;
}

static int pfkey_broadcast_one(struct sk_buff *skb, gfp_t allocation,
                               struct sock *sk)
{
        int err = -ENOBUFS;

        if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf)
                return err;

        skb = skb_clone(skb, allocation);

        if (skb) {
                skb_set_owner_r(skb, sk);
                skb_queue_tail(&sk->sk_receive_queue, skb);
                sk->sk_data_ready(sk);
                err = 0;
        }
        return err;
}

/* Send SKB to all pfkey sockets matching selected criteria.  */
#define BROADCAST_ALL           0
#define BROADCAST_ONE           1
#define BROADCAST_REGISTERED    2
#define BROADCAST_PROMISC_ONLY  4
static int pfkey_broadcast(struct sk_buff *skb, gfp_t allocation,
                           int broadcast_flags, struct sock *one_sk,
                           struct net *net)
{
        struct netns_pfkey *net_pfkey = net_generic(net, pfkey_net_id);
        struct sock *sk;
        int err = -ESRCH;

        /* XXX Do we need something like netlink_overrun?  I think
         * XXX PF_KEY socket apps will not mind current behavior.
         */
        if (!skb)
                return -ENOMEM;

        rcu_read_lock();
        sk_for_each_rcu(sk, &net_pfkey->table) {
                struct pfkey_sock *pfk = pfkey_sk(sk);
                int err2;

                /* Yes, it means that if you are meant to receive this
                 * pfkey message you receive it twice as promiscuous
                 * socket.
                 */
                if (pfk->promisc)
                        pfkey_broadcast_one(skb, GFP_ATOMIC, sk);

                /* the exact target will be processed later */
                if (sk == one_sk)
                        continue;
                if (broadcast_flags != BROADCAST_ALL) {
                        if (broadcast_flags & BROADCAST_PROMISC_ONLY)
                                continue;
                        if ((broadcast_flags & BROADCAST_REGISTERED) &&
                            !pfk->registered)
                                continue;
                        if (broadcast_flags & BROADCAST_ONE)
                                continue;
                }

                err2 = pfkey_broadcast_one(skb, GFP_ATOMIC, sk);

                /* Error is cleared after successful sending to at least one
                 * registered KM */
                if ((broadcast_flags & BROADCAST_REGISTERED) && err)
                        err = err2;
        }
        rcu_read_unlock();

        if (one_sk != NULL)
                err = pfkey_broadcast_one(skb, allocation, one_sk);

        kfree_skb(skb);
        return err;
}

static int pfkey_do_dump(struct pfkey_sock *pfk)
{
        struct sadb_msg *hdr;
        int rc;

        mutex_lock(&pfk->dump_lock);
        if (!pfk->dump.dump) {
                rc = 0;
                goto out;
        }

        rc = pfk->dump.dump(pfk);
        if (rc == -ENOBUFS) {
                rc = 0;
                goto out;
        }

        if (pfk->dump.skb) {
                if (!pfkey_can_dump(&pfk->sk)) {
                        rc = 0;
                        goto out;
                }

                hdr = (struct sadb_msg *) pfk->dump.skb->data;
                hdr->sadb_msg_seq = 0;
                hdr->sadb_msg_errno = rc;
                pfkey_broadcast(pfk->dump.skb, GFP_ATOMIC, BROADCAST_ONE,
                                &pfk->sk, sock_net(&pfk->sk));
                pfk->dump.skb = NULL;
        }

        pfkey_terminate_dump(pfk);

out:
        mutex_unlock(&pfk->dump_lock);
        return rc;
}

static inline void pfkey_hdr_dup(struct sadb_msg *new,
                                 const struct sadb_msg *orig)
{
        *new = *orig;
}

static int pfkey_error(const struct sadb_msg *orig, int err, struct sock *sk)
{
        struct sk_buff *skb = alloc_skb(sizeof(struct sadb_msg) + 16, GFP_KERNEL);
        struct sadb_msg *hdr;

        if (!skb)
                return -ENOBUFS;

        /* Woe be to the platform trying to support PFKEY yet
         * having normal errnos outside the 1-255 range, inclusive.
         */
        err = -err;
        if (err == ERESTARTSYS ||
            err == ERESTARTNOHAND ||
            err == ERESTARTNOINTR)
                err = EINTR;
        if (err >= 512)
                err = EINVAL;
        BUG_ON(err <= 0 || err >= 256);

        hdr = skb_put(skb, sizeof(struct sadb_msg));
        pfkey_hdr_dup(hdr, orig);
        hdr->sadb_msg_errno = (uint8_t) err;
        hdr->sadb_msg_len = (sizeof(struct sadb_msg) /
                             sizeof(uint64_t));

        pfkey_broadcast(skb, GFP_KERNEL, BROADCAST_ONE, sk, sock_net(sk));

        return 0;
}

static const u8 sadb_ext_min_len[] = {
        [SADB_EXT_RESERVED]             = (u8) 0,
        [SADB_EXT_SA]                   = (u8) sizeof(struct sadb_sa),
        [SADB_EXT_LIFETIME_CURRENT]     = (u8) sizeof(struct sadb_lifetime),
        [SADB_EXT_LIFETIME_HARD]        = (u8) sizeof(struct sadb_lifetime),
        [SADB_EXT_LIFETIME_SOFT]        = (u8) sizeof(struct sadb_lifetime),
        [SADB_EXT_ADDRESS_SRC]          = (u8) sizeof(struct sadb_address),
        [SADB_EXT_ADDRESS_DST]          = (u8) sizeof(struct sadb_address),
        [SADB_EXT_ADDRESS_PROXY]        = (u8) sizeof(struct sadb_address),
        [SADB_EXT_KEY_AUTH]             = (u8) sizeof(struct sadb_key),
        [SADB_EXT_KEY_ENCRYPT]          = (u8) sizeof(struct sadb_key),
        [SADB_EXT_IDENTITY_SRC]         = (u8) sizeof(struct sadb_ident),
        [SADB_EXT_IDENTITY_DST]         = (u8) sizeof(struct sadb_ident),
        [SADB_EXT_SENSITIVITY]          = (u8) sizeof(struct sadb_sens),
        [SADB_EXT_PROPOSAL]             = (u8) sizeof(struct sadb_prop),
        [SADB_EXT_SUPPORTED_AUTH]       = (u8) sizeof(struct sadb_supported),
        [SADB_EXT_SUPPORTED_ENCRYPT]    = (u8) sizeof(struct sadb_supported),
        [SADB_EXT_SPIRANGE]             = (u8) sizeof(struct sadb_spirange),
        [SADB_X_EXT_KMPRIVATE]          = (u8) sizeof(struct sadb_x_kmprivate),
        [SADB_X_EXT_POLICY]             = (u8) sizeof(struct sadb_x_policy),
        [SADB_X_EXT_SA2]                = (u8) sizeof(struct sadb_x_sa2),
        [SADB_X_EXT_NAT_T_TYPE]         = (u8) sizeof(struct sadb_x_nat_t_type),
        [SADB_X_EXT_NAT_T_SPORT]        = (u8) sizeof(struct sadb_x_nat_t_port),
        [SADB_X_EXT_NAT_T_DPORT]        = (u8) sizeof(struct sadb_x_nat_t_port),
        [SADB_X_EXT_NAT_T_OA]           = (u8) sizeof(struct sadb_address),
        [SADB_X_EXT_SEC_CTX]            = (u8) sizeof(struct sadb_x_sec_ctx),
        [SADB_X_EXT_KMADDRESS]          = (u8) sizeof(struct sadb_x_kmaddress),
        [SADB_X_EXT_FILTER]             = (u8) sizeof(struct sadb_x_filter),
};

/* Verify sadb_address_{len,prefixlen} against sa_family.  */
static int verify_address_len(const void *p)
{
        const struct sadb_address *sp = p;
        const struct sockaddr *addr = (const struct sockaddr *)(sp + 1);
        const struct sockaddr_in *sin;
#if IS_ENABLED(CONFIG_IPV6)
        const struct sockaddr_in6 *sin6;
#endif
        int len;

        if (sp->sadb_address_len <
            DIV_ROUND_UP(sizeof(*sp) + offsetofend(typeof(*addr), sa_family),
                         sizeof(uint64_t)))
                return -EINVAL;

        switch (addr->sa_family) {
        case AF_INET:
                len = DIV_ROUND_UP(sizeof(*sp) + sizeof(*sin), sizeof(uint64_t));
                if (sp->sadb_address_len != len ||
                    sp->sadb_address_prefixlen > 32)
                        return -EINVAL;
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                len = DIV_ROUND_UP(sizeof(*sp) + sizeof(*sin6), sizeof(uint64_t));
                if (sp->sadb_address_len != len ||
                    sp->sadb_address_prefixlen > 128)
                        return -EINVAL;
                break;
#endif
        default:
                /* It is user using kernel to keep track of security
                 * associations for another protocol, such as
                 * OSPF/RSVP/RIPV2/MIP.  It is user's job to verify
                 * lengths.
                 *
                 * XXX Actually, association/policy database is not yet
                 * XXX able to cope with arbitrary sockaddr families.
                 * XXX When it can, remove this -EINVAL.  -DaveM
                 */
                return -EINVAL;
        }

        return 0;
}

static inline int sadb_key_len(const struct sadb_key *key)
{
        int key_bytes = DIV_ROUND_UP(key->sadb_key_bits, 8);

        return DIV_ROUND_UP(sizeof(struct sadb_key) + key_bytes,
                            sizeof(uint64_t));
}

static int verify_key_len(const void *p)
{
        const struct sadb_key *key = p;

        if (sadb_key_len(key) > key->sadb_key_len)
                return -EINVAL;

        return 0;
}

static inline int pfkey_sec_ctx_len(const struct sadb_x_sec_ctx *sec_ctx)
{
        return DIV_ROUND_UP(sizeof(struct sadb_x_sec_ctx) +
                            sec_ctx->sadb_x_ctx_len,
                            sizeof(uint64_t));
}

static inline int verify_sec_ctx_len(const void *p)
{
        const struct sadb_x_sec_ctx *sec_ctx = p;
        int len = sec_ctx->sadb_x_ctx_len;

        if (len > PAGE_SIZE)
                return -EINVAL;

        len = pfkey_sec_ctx_len(sec_ctx);

        if (sec_ctx->sadb_x_sec_len != len)
                return -EINVAL;

        return 0;
}

static inline struct xfrm_user_sec_ctx *pfkey_sadb2xfrm_user_sec_ctx(const struct sadb_x_sec_ctx *sec_ctx,
                                                                     gfp_t gfp)
{
        struct xfrm_user_sec_ctx *uctx = NULL;
        int ctx_size = sec_ctx->sadb_x_ctx_len;

        uctx = kmalloc((sizeof(*uctx)+ctx_size), gfp);

        if (!uctx)
                return NULL;

        uctx->len = pfkey_sec_ctx_len(sec_ctx);
        uctx->exttype = sec_ctx->sadb_x_sec_exttype;
        uctx->ctx_doi = sec_ctx->sadb_x_ctx_doi;
        uctx->ctx_alg = sec_ctx->sadb_x_ctx_alg;
        uctx->ctx_len = sec_ctx->sadb_x_ctx_len;
        memcpy(uctx + 1, sec_ctx + 1,
               uctx->ctx_len);

        return uctx;
}

static int present_and_same_family(const struct sadb_address *src,
                                   const struct sadb_address *dst)
{
        const struct sockaddr *s_addr, *d_addr;

        if (!src || !dst)
                return 0;

        s_addr = (const struct sockaddr *)(src + 1);
        d_addr = (const struct sockaddr *)(dst + 1);
        if (s_addr->sa_family != d_addr->sa_family)
                return 0;
        if (s_addr->sa_family != AF_INET
#if IS_ENABLED(CONFIG_IPV6)
            && s_addr->sa_family != AF_INET6
#endif
                )
                return 0;

        return 1;
}

static int parse_exthdrs(struct sk_buff *skb, const struct sadb_msg *hdr, void **ext_hdrs)
{
        const char *p = (char *) hdr;
        int len = skb->len;

        len -= sizeof(*hdr);
        p += sizeof(*hdr);
        while (len > 0) {
                const struct sadb_ext *ehdr = (const struct sadb_ext *) p;
                uint16_t ext_type;
                int ext_len;

                if (len < sizeof(*ehdr))
                        return -EINVAL;

                ext_len  = ehdr->sadb_ext_len;
                ext_len *= sizeof(uint64_t);
                ext_type = ehdr->sadb_ext_type;
                if (ext_len < sizeof(uint64_t) ||
                    ext_len > len ||
                    ext_type == SADB_EXT_RESERVED)
                        return -EINVAL;

                if (ext_type <= SADB_EXT_MAX) {
                        int min = (int) sadb_ext_min_len[ext_type];
                        if (ext_len < min)
                                return -EINVAL;
                        if (ext_hdrs[ext_type-1] != NULL)
                                return -EINVAL;
                        switch (ext_type) {
                        case SADB_EXT_ADDRESS_SRC:
                        case SADB_EXT_ADDRESS_DST:
                        case SADB_EXT_ADDRESS_PROXY:
                        case SADB_X_EXT_NAT_T_OA:
                                if (verify_address_len(p))
                                        return -EINVAL;
                                break;
                        case SADB_X_EXT_SEC_CTX:
                                if (verify_sec_ctx_len(p))
                                        return -EINVAL;
                                break;
                        case SADB_EXT_KEY_AUTH:
                        case SADB_EXT_KEY_ENCRYPT:
                                if (verify_key_len(p))
                                        return -EINVAL;
                                break;
                        default:
                                break;
                        }
                        ext_hdrs[ext_type-1] = (void *) p;
                }
                p   += ext_len;
                len -= ext_len;
        }

        return 0;
}

static uint16_t
pfkey_satype2proto(uint8_t satype)
{
        switch (satype) {
        case SADB_SATYPE_UNSPEC:
                return IPSEC_PROTO_ANY;
        case SADB_SATYPE_AH:
                return IPPROTO_AH;
        case SADB_SATYPE_ESP:
                return IPPROTO_ESP;
        case SADB_X_SATYPE_IPCOMP:
                return IPPROTO_COMP;
        default:
                return 0;
        }
        /* NOTREACHED */
}

static uint8_t
pfkey_proto2satype(uint16_t proto)
{
        switch (proto) {
        case IPPROTO_AH:
                return SADB_SATYPE_AH;
        case IPPROTO_ESP:
                return SADB_SATYPE_ESP;
        case IPPROTO_COMP:
                return SADB_X_SATYPE_IPCOMP;
        default:
                return 0;
        }
        /* NOTREACHED */
}

/* BTW, this scheme means that there is no way with PFKEY2 sockets to
 * say specifically 'just raw sockets' as we encode them as 255.
 */

static uint8_t pfkey_proto_to_xfrm(uint8_t proto)
{
        return proto == IPSEC_PROTO_ANY ? 0 : proto;
}

static uint8_t pfkey_proto_from_xfrm(uint8_t proto)
{
        return proto ? proto : IPSEC_PROTO_ANY;
}

static inline int pfkey_sockaddr_len(sa_family_t family)
{
        switch (family) {
        case AF_INET:
                return sizeof(struct sockaddr_in);
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                return sizeof(struct sockaddr_in6);
#endif
        }
        return 0;
}

static
int pfkey_sockaddr_extract(const struct sockaddr *sa, xfrm_address_t *xaddr)
{
        switch (sa->sa_family) {
        case AF_INET:
                xaddr->a4 =
                        ((struct sockaddr_in *)sa)->sin_addr.s_addr;
                return AF_INET;
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                memcpy(xaddr->a6,
                       &((struct sockaddr_in6 *)sa)->sin6_addr,
                       sizeof(struct in6_addr));
                return AF_INET6;
#endif
        }
        return 0;
}

static
int pfkey_sadb_addr2xfrm_addr(const struct sadb_address *addr, xfrm_address_t *xaddr)
{
        return pfkey_sockaddr_extract((struct sockaddr *)(addr + 1),
                                      xaddr);
}

static struct  xfrm_state *pfkey_xfrm_state_lookup(struct net *net, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        const struct sadb_sa *sa;
        const struct sadb_address *addr;
        uint16_t proto;
        unsigned short family;
        xfrm_address_t *xaddr;

        sa = ext_hdrs[SADB_EXT_SA - 1];
        if (sa == NULL)
                return NULL;

        proto = pfkey_satype2proto(hdr->sadb_msg_satype);
        if (proto == 0)
                return NULL;

        /* sadb_address_len should be checked by caller */
        addr = ext_hdrs[SADB_EXT_ADDRESS_DST - 1];
        if (addr == NULL)
                return NULL;

        family = ((const struct sockaddr *)(addr + 1))->sa_family;
        switch (family) {
        case AF_INET:
                xaddr = (xfrm_address_t *)&((const struct sockaddr_in *)(addr + 1))->sin_addr;
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                xaddr = (xfrm_address_t *)&((const struct sockaddr_in6 *)(addr + 1))->sin6_addr;
                break;
#endif
        default:
                xaddr = NULL;
        }

        if (!xaddr)
                return NULL;

        return xfrm_state_lookup(net, DUMMY_MARK, xaddr, sa->sadb_sa_spi, proto, family);
}

#define PFKEY_ALIGN8(a) (1 + (((a) - 1) | (8 - 1)))

static int
pfkey_sockaddr_size(sa_family_t family)
{
        return PFKEY_ALIGN8(pfkey_sockaddr_len(family));
}

static inline int pfkey_mode_from_xfrm(int mode)
{
        switch(mode) {
        case XFRM_MODE_TRANSPORT:
                return IPSEC_MODE_TRANSPORT;
        case XFRM_MODE_TUNNEL:
                return IPSEC_MODE_TUNNEL;
        case XFRM_MODE_BEET:
                return IPSEC_MODE_BEET;
        default:
                return -1;
        }
}

static inline int pfkey_mode_to_xfrm(int mode)
{
        switch(mode) {
        case IPSEC_MODE_ANY:    /*XXX*/
        case IPSEC_MODE_TRANSPORT:
                return XFRM_MODE_TRANSPORT;
        case IPSEC_MODE_TUNNEL:
                return XFRM_MODE_TUNNEL;
        case IPSEC_MODE_BEET:
                return XFRM_MODE_BEET;
        default:
                return -1;
        }
}

static unsigned int pfkey_sockaddr_fill(const xfrm_address_t *xaddr, __be16 port,
                                        struct sockaddr *sa,
                                        unsigned short family)
{
        switch (family) {
        case AF_INET:
            {
                struct sockaddr_in *sin = (struct sockaddr_in *)sa;
                sin->sin_family = AF_INET;
                sin->sin_port = port;
                sin->sin_addr.s_addr = xaddr->a4;
                memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
                return 32;
            }
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
            {
                struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
                sin6->sin6_family = AF_INET6;
                sin6->sin6_port = port;
                sin6->sin6_flowinfo = 0;
                sin6->sin6_addr = xaddr->in6;
                sin6->sin6_scope_id = 0;
                return 128;
            }
#endif
        }
        return 0;
}

static struct sk_buff *__pfkey_xfrm_state2msg(const struct xfrm_state *x,
                                              int add_keys, int hsc)
{
        struct sk_buff *skb;
        struct sadb_msg *hdr;
        struct sadb_sa *sa;
        struct sadb_lifetime *lifetime;
        struct sadb_address *addr;
        struct sadb_key *key;
        struct sadb_x_sa2 *sa2;
        struct sadb_x_sec_ctx *sec_ctx;
        struct xfrm_sec_ctx *xfrm_ctx;
        int ctx_size = 0;
        int size;
        int auth_key_size = 0;
        int encrypt_key_size = 0;
        int sockaddr_size;
        struct xfrm_encap_tmpl *natt = NULL;
        int mode;

        /* address family check */
        sockaddr_size = pfkey_sockaddr_size(x->props.family);
        if (!sockaddr_size)
                return ERR_PTR(-EINVAL);

        /* base, SA, (lifetime (HSC),) address(SD), (address(P),)
           key(AE), (identity(SD),) (sensitivity)> */
        size = sizeof(struct sadb_msg) +sizeof(struct sadb_sa) +
                sizeof(struct sadb_lifetime) +
                ((hsc & 1) ? sizeof(struct sadb_lifetime) : 0) +
                ((hsc & 2) ? sizeof(struct sadb_lifetime) : 0) +
                        sizeof(struct sadb_address)*2 +
                                sockaddr_size*2 +
                                        sizeof(struct sadb_x_sa2);

        if ((xfrm_ctx = x->security)) {
                ctx_size = PFKEY_ALIGN8(xfrm_ctx->ctx_len);
                size += sizeof(struct sadb_x_sec_ctx) + ctx_size;
        }

        /* identity & sensitivity */
        if (!xfrm_addr_equal(&x->sel.saddr, &x->props.saddr, x->props.family))
                size += sizeof(struct sadb_address) + sockaddr_size;

        if (add_keys) {
                if (x->aalg && x->aalg->alg_key_len) {
                        auth_key_size =
                                PFKEY_ALIGN8((x->aalg->alg_key_len + 7) / 8);
                        size += sizeof(struct sadb_key) + auth_key_size;
                }
                if (x->ealg && x->ealg->alg_key_len) {
                        encrypt_key_size =
                                PFKEY_ALIGN8((x->ealg->alg_key_len+7) / 8);
                        size += sizeof(struct sadb_key) + encrypt_key_size;
                }
        }
        if (x->encap)
                natt = x->encap;

        if (natt && natt->encap_type) {
                size += sizeof(struct sadb_x_nat_t_type);
                size += sizeof(struct sadb_x_nat_t_port);
                size += sizeof(struct sadb_x_nat_t_port);
        }

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

        /* call should fill header later */
        hdr = skb_put(skb, sizeof(struct sadb_msg));
        memset(hdr, 0, size);   /* XXX do we need this ? */
        hdr->sadb_msg_len = size / sizeof(uint64_t);

        /* sa */
        sa = skb_put(skb, sizeof(struct sadb_sa));
        sa->sadb_sa_len = sizeof(struct sadb_sa)/sizeof(uint64_t);
        sa->sadb_sa_exttype = SADB_EXT_SA;
        sa->sadb_sa_spi = x->id.spi;
        sa->sadb_sa_replay = x->props.replay_window;
        switch (x->km.state) {
        case XFRM_STATE_VALID:
                sa->sadb_sa_state = x->km.dying ?
                        SADB_SASTATE_DYING : SADB_SASTATE_MATURE;
                break;
        case XFRM_STATE_ACQ:
                sa->sadb_sa_state = SADB_SASTATE_LARVAL;
                break;
        default:
                sa->sadb_sa_state = SADB_SASTATE_DEAD;
                break;
        }
        sa->sadb_sa_auth = 0;
        if (x->aalg) {
                struct xfrm_algo_desc *a = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
                sa->sadb_sa_auth = (a && a->pfkey_supported) ?
                                        a->desc.sadb_alg_id : 0;
        }
        sa->sadb_sa_encrypt = 0;
        BUG_ON(x->ealg && x->calg);
        if (x->ealg) {
                struct xfrm_algo_desc *a = xfrm_ealg_get_byname(x->ealg->alg_name, 0);
                sa->sadb_sa_encrypt = (a && a->pfkey_supported) ?
                                        a->desc.sadb_alg_id : 0;
        }
        /* KAME compatible: sadb_sa_encrypt is overloaded with calg id */
        if (x->calg) {
                struct xfrm_algo_desc *a = xfrm_calg_get_byname(x->calg->alg_name, 0);
                sa->sadb_sa_encrypt = (a && a->pfkey_supported) ?
                                        a->desc.sadb_alg_id : 0;
        }

        sa->sadb_sa_flags = 0;
        if (x->props.flags & XFRM_STATE_NOECN)
                sa->sadb_sa_flags |= SADB_SAFLAGS_NOECN;
        if (x->props.flags & XFRM_STATE_DECAP_DSCP)
                sa->sadb_sa_flags |= SADB_SAFLAGS_DECAP_DSCP;
        if (x->props.flags & XFRM_STATE_NOPMTUDISC)
                sa->sadb_sa_flags |= SADB_SAFLAGS_NOPMTUDISC;

        /* hard time */
        if (hsc & 2) {
                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(x->lft.hard_packet_limit);
                lifetime->sadb_lifetime_bytes = _X2KEY(x->lft.hard_byte_limit);
                lifetime->sadb_lifetime_addtime = x->lft.hard_add_expires_seconds;
                lifetime->sadb_lifetime_usetime = x->lft.hard_use_expires_seconds;
        }
        /* soft time */
        if (hsc & 1) {
                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(x->lft.soft_packet_limit);
                lifetime->sadb_lifetime_bytes = _X2KEY(x->lft.soft_byte_limit);
                lifetime->sadb_lifetime_addtime = x->lft.soft_add_expires_seconds;
                lifetime->sadb_lifetime_usetime = x->lft.soft_use_expires_seconds;
        }
        /* current time */
        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 = x->curlft.packets;
        lifetime->sadb_lifetime_bytes = x->curlft.bytes;
        lifetime->sadb_lifetime_addtime = x->curlft.add_time;
        lifetime->sadb_lifetime_usetime = x->curlft.use_time;
        /* src address */
        addr = 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;
        /* "if the ports are non-zero, then the sadb_address_proto field,
           normally zero, MUST be filled in with the transport
           protocol's number." - RFC2367 */
        addr->sadb_address_proto = 0;
        addr->sadb_address_reserved = 0;

        addr->sadb_address_prefixlen =
                pfkey_sockaddr_fill(&x->props.saddr, 0,
                                    (struct sockaddr *) (addr + 1),
                                    x->props.family);
        BUG_ON(!addr->sadb_address_prefixlen);

        /* dst address */
        addr = 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 = 0;
        addr->sadb_address_reserved = 0;

        addr->sadb_address_prefixlen =
                pfkey_sockaddr_fill(&x->id.daddr, 0,
                                    (struct sockaddr *) (addr + 1),
                                    x->props.family);
        BUG_ON(!addr->sadb_address_prefixlen);

        if (!xfrm_addr_equal(&x->sel.saddr, &x->props.saddr,
                             x->props.family)) {
                addr = 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_PROXY;
                addr->sadb_address_proto =
                        pfkey_proto_from_xfrm(x->sel.proto);
                addr->sadb_address_prefixlen = x->sel.prefixlen_s;
                addr->sadb_address_reserved = 0;

                pfkey_sockaddr_fill(&x->sel.saddr, x->sel.sport,
                                    (struct sockaddr *) (addr + 1),
                                    x->props.family);
        }

        /* auth key */
        if (add_keys && auth_key_size) {
                key = skb_put(skb, sizeof(struct sadb_key) + auth_key_size);
                key->sadb_key_len = (sizeof(struct sadb_key) + auth_key_size) /
                        sizeof(uint64_t);
                key->sadb_key_exttype = SADB_EXT_KEY_AUTH;
                key->sadb_key_bits = x->aalg->alg_key_len;
                key->sadb_key_reserved = 0;
                memcpy(key + 1, x->aalg->alg_key, (x->aalg->alg_key_len+7)/8);
        }
        /* encrypt key */
        if (add_keys && encrypt_key_size) {
                key = skb_put(skb, sizeof(struct sadb_key) + encrypt_key_size);
                key->sadb_key_len = (sizeof(struct sadb_key) +
                                     encrypt_key_size) / sizeof(uint64_t);
                key->sadb_key_exttype = SADB_EXT_KEY_ENCRYPT;
                key->sadb_key_bits = x->ealg->alg_key_len;
                key->sadb_key_reserved = 0;
                memcpy(key + 1, x->ealg->alg_key,
                       (x->ealg->alg_key_len+7)/8);
        }

        /* sa */
        sa2 = skb_put(skb, sizeof(struct sadb_x_sa2));
        sa2->sadb_x_sa2_len = sizeof(struct sadb_x_sa2)/sizeof(uint64_t);
        sa2->sadb_x_sa2_exttype = SADB_X_EXT_SA2;
        if ((mode = pfkey_mode_from_xfrm(x->props.mode)) < 0) {
                kfree_skb(skb);
                return ERR_PTR(-EINVAL);
        }
        sa2->sadb_x_sa2_mode = mode;
        sa2->sadb_x_sa2_reserved1 = 0;
        sa2->sadb_x_sa2_reserved2 = 0;
        sa2->sadb_x_sa2_sequence = 0;
        sa2->sadb_x_sa2_reqid = x->props.reqid;

        if (natt && natt->encap_type) {
                struct sadb_x_nat_t_type *n_type;
                struct sadb_x_nat_t_port *n_port;

                /* type */
                n_type = skb_put(skb, sizeof(*n_type));
                n_type->sadb_x_nat_t_type_len = sizeof(*n_type)/sizeof(uint64_t);
                n_type->sadb_x_nat_t_type_exttype = SADB_X_EXT_NAT_T_TYPE;
                n_type->sadb_x_nat_t_type_type = natt->encap_type;
                n_type->sadb_x_nat_t_type_reserved[0] = 0;
                n_type->sadb_x_nat_t_type_reserved[1] = 0;
                n_type->sadb_x_nat_t_type_reserved[2] = 0;

                /* source port */
                n_port = skb_put(skb, sizeof(*n_port));
                n_port->sadb_x_nat_t_port_len = sizeof(*n_port)/sizeof(uint64_t);
                n_port->sadb_x_nat_t_port_exttype = SADB_X_EXT_NAT_T_SPORT;
                n_port->sadb_x_nat_t_port_port = natt->encap_sport;
                n_port->sadb_x_nat_t_port_reserved = 0;

                /* dest port */
                n_port = skb_put(skb, sizeof(*n_port));
                n_port->sadb_x_nat_t_port_len = sizeof(*n_port)/sizeof(uint64_t);
                n_port->sadb_x_nat_t_port_exttype = SADB_X_EXT_NAT_T_DPORT;
                n_port->sadb_x_nat_t_port_port = natt->encap_dport;
                n_port->sadb_x_nat_t_port_reserved = 0;
        }

        /* security context */
        if (xfrm_ctx) {
                sec_ctx = skb_put(skb,
                                  sizeof(struct sadb_x_sec_ctx) + ctx_size);
                sec_ctx->sadb_x_sec_len =
                  (sizeof(struct sadb_x_sec_ctx) + 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);
        }

        return skb;
}


static inline struct sk_buff *pfkey_xfrm_state2msg(const struct xfrm_state *x)
{
        struct sk_buff *skb;

        skb = __pfkey_xfrm_state2msg(x, 1, 3);

        return skb;
}

static inline struct sk_buff *pfkey_xfrm_state2msg_expire(const struct xfrm_state *x,
                                                          int hsc)
{
        return __pfkey_xfrm_state2msg(x, 0, hsc);
}

static struct xfrm_state * pfkey_msg2xfrm_state(struct net *net,
                                                const struct sadb_msg *hdr,
                                                void * const *ext_hdrs)
{
        struct xfrm_state *x;
        const struct sadb_lifetime *lifetime;
        const struct sadb_sa *sa;
        const struct sadb_key *key;
        const struct sadb_x_sec_ctx *sec_ctx;
        uint16_t proto;
        int err;


        sa = ext_hdrs[SADB_EXT_SA - 1];
        if (!sa ||
            !present_and_same_family(ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
                                     ext_hdrs[SADB_EXT_ADDRESS_DST-1]))
                return ERR_PTR(-EINVAL);
        if (hdr->sadb_msg_satype == SADB_SATYPE_ESP &&
            !ext_hdrs[SADB_EXT_KEY_ENCRYPT-1])
                return ERR_PTR(-EINVAL);
        if (hdr->sadb_msg_satype == SADB_SATYPE_AH &&
            !ext_hdrs[SADB_EXT_KEY_AUTH-1])
                return ERR_PTR(-EINVAL);
        if (!!ext_hdrs[SADB_EXT_LIFETIME_HARD-1] !=
            !!ext_hdrs[SADB_EXT_LIFETIME_SOFT-1])
                return ERR_PTR(-EINVAL);

        proto = pfkey_satype2proto(hdr->sadb_msg_satype);
        if (proto == 0)
                return ERR_PTR(-EINVAL);

        /* default error is no buffer space */
        err = -ENOBUFS;

        /* RFC2367:

   Only SADB_SASTATE_MATURE SAs may be submitted in an SADB_ADD message.
   SADB_SASTATE_LARVAL SAs are created by SADB_GETSPI and it is not
   sensible to add a new SA in the DYING or SADB_SASTATE_DEAD state.
   Therefore, the sadb_sa_state field of all submitted SAs MUST be
   SADB_SASTATE_MATURE and the kernel MUST return an error if this is
   not true.

           However, KAME setkey always uses SADB_SASTATE_LARVAL.
           Hence, we have to _ignore_ sadb_sa_state, which is also reasonable.
         */
        if (sa->sadb_sa_auth > SADB_AALG_MAX ||
            (hdr->sadb_msg_satype == SADB_X_SATYPE_IPCOMP &&
             sa->sadb_sa_encrypt > SADB_X_CALG_MAX) ||
            sa->sadb_sa_encrypt > SADB_EALG_MAX)
                return ERR_PTR(-EINVAL);
        key = ext_hdrs[SADB_EXT_KEY_AUTH - 1];
        if (key != NULL &&
            sa->sadb_sa_auth != SADB_X_AALG_NULL &&
            key->sadb_key_bits == 0)
                return ERR_PTR(-EINVAL);
        key = ext_hdrs[SADB_EXT_KEY_ENCRYPT-1];
        if (key != NULL &&
            sa->sadb_sa_encrypt != SADB_EALG_NULL &&
            key->sadb_key_bits == 0)
                return ERR_PTR(-EINVAL);

        x = xfrm_state_alloc(net);
        if (x == NULL)
                return ERR_PTR(-ENOBUFS);

        x->id.proto = proto;
        x->id.spi = sa->sadb_sa_spi;
        x->props.replay_window = min_t(unsigned int, sa->sadb_sa_replay,
                                        (sizeof(x->replay.bitmap) * 8));
        if (sa->sadb_sa_flags & SADB_SAFLAGS_NOECN)
                x->props.flags |= XFRM_STATE_NOECN;
        if (sa->sadb_sa_flags & SADB_SAFLAGS_DECAP_DSCP)
                x->props.flags |= XFRM_STATE_DECAP_DSCP;
        if (sa->sadb_sa_flags & SADB_SAFLAGS_NOPMTUDISC)
                x->props.flags |= XFRM_STATE_NOPMTUDISC;

        lifetime = ext_hdrs[SADB_EXT_LIFETIME_HARD - 1];
        if (lifetime != NULL) {
                x->lft.hard_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
                x->lft.hard_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
                x->lft.hard_add_expires_seconds = lifetime->sadb_lifetime_addtime;
                x->lft.hard_use_expires_seconds = lifetime->sadb_lifetime_usetime;
        }
        lifetime = ext_hdrs[SADB_EXT_LIFETIME_SOFT - 1];
        if (lifetime != NULL) {
                x->lft.soft_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
                x->lft.soft_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
                x->lft.soft_add_expires_seconds = lifetime->sadb_lifetime_addtime;
                x->lft.soft_use_expires_seconds = lifetime->sadb_lifetime_usetime;
        }

        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, GFP_KERNEL);

                if (!uctx)
                        goto out;

                err = security_xfrm_state_alloc(x, uctx);
                kfree(uctx);

                if (err)
                        goto out;
        }

        err = -ENOBUFS;
        key = ext_hdrs[SADB_EXT_KEY_AUTH - 1];
        if (sa->sadb_sa_auth) {
                int keysize = 0;
                struct xfrm_algo_desc *a = xfrm_aalg_get_byid(sa->sadb_sa_auth);
                if (!a || !a->pfkey_supported) {
                        err = -ENOSYS;
                        goto out;
                }
                if (key)
                        keysize = (key->sadb_key_bits + 7) / 8;
                x->aalg = kmalloc(sizeof(*x->aalg) + keysize, GFP_KERNEL);
                if (!x->aalg) {
                        err = -ENOMEM;
                        goto out;
                }
                strcpy(x->aalg->alg_name, a->name);
                x->aalg->alg_key_len = 0;
                if (key) {
                        x->aalg->alg_key_len = key->sadb_key_bits;
                        memcpy(x->aalg->alg_key, key+1, keysize);
                }
                x->aalg->alg_trunc_len = a->uinfo.auth.icv_truncbits;
                x->props.aalgo = sa->sadb_sa_auth;
                /* x->algo.flags = sa->sadb_sa_flags; */
        }
        if (sa->sadb_sa_encrypt) {
                if (hdr->sadb_msg_satype == SADB_X_SATYPE_IPCOMP) {
                        struct xfrm_algo_desc *a = xfrm_calg_get_byid(sa->sadb_sa_encrypt);
                        if (!a || !a->pfkey_supported) {
                                err = -ENOSYS;
                                goto out;
                        }
                        x->calg = kmalloc(sizeof(*x->calg), GFP_KERNEL);
                        if (!x->calg) {
                                err = -ENOMEM;
                                goto out;
                        }
                        strcpy(x->calg->alg_name, a->name);
                        x->props.calgo = sa->sadb_sa_encrypt;
                } else {
                        int keysize = 0;
                        struct xfrm_algo_desc *a = xfrm_ealg_get_byid(sa->sadb_sa_encrypt);
                        if (!a || !a->pfkey_supported) {
                                err = -ENOSYS;
                                goto out;
                        }
                        key = (struct sadb_key*) ext_hdrs[SADB_EXT_KEY_ENCRYPT-1];
                        if (key)
                                keysize = (key->sadb_key_bits + 7) / 8;
                        x->ealg = kmalloc(sizeof(*x->ealg) + keysize, GFP_KERNEL);
                        if (!x->ealg) {
                                err = -ENOMEM;
                                goto out;
                        }
                        strcpy(x->ealg->alg_name, a->name);
                        x->ealg->alg_key_len = 0;
                        if (key) {
                                x->ealg->alg_key_len = key->sadb_key_bits;
                                memcpy(x->ealg->alg_key, key+1, keysize);
                        }
                        x->props.ealgo = sa->sadb_sa_encrypt;
                        x->geniv = a->uinfo.encr.geniv;
                }
        }
        /* x->algo.flags = sa->sadb_sa_flags; */

        x->props.family = pfkey_sadb_addr2xfrm_addr((struct sadb_address *) ext_hdrs[SADB_EXT_ADDRESS_SRC-1],
                                                    &x->props.saddr);
        pfkey_sadb_addr2xfrm_addr((struct sadb_address *) ext_hdrs[SADB_EXT_ADDRESS_DST-1],
                                  &x->id.daddr);

        if (ext_hdrs[SADB_X_EXT_SA2-1]) {
                const struct sadb_x_sa2 *sa2 = ext_hdrs[SADB_X_EXT_SA2-1];
                int mode = pfkey_mode_to_xfrm(sa2->sadb_x_sa2_mode);
                if (mode < 0) {
                        err = -EINVAL;
                        goto out;
                }
                x->props.mode = mode;
                x->props.reqid = sa2->sadb_x_sa2_reqid;
        }

        if (ext_hdrs[SADB_EXT_ADDRESS_PROXY-1]) {
                const struct sadb_address *addr = ext_hdrs[SADB_EXT_ADDRESS_PROXY-1];

                /* Nobody uses this, but we try. */
                x->sel.family = pfkey_sadb_addr2xfrm_addr(addr, &x->sel.saddr);
                x->sel.prefixlen_s = addr->sadb_address_prefixlen;
        }

        if (!x->sel.family)
                x->sel.family = x->props.family;

        if (ext_hdrs[SADB_X_EXT_NAT_T_TYPE-1]) {
                const struct sadb_x_nat_t_type* n_type;
                struct xfrm_encap_tmpl *natt;

                x->encap = kmalloc(sizeof(*x->encap), GFP_KERNEL);
                if (!x->encap) {
                        err = -ENOMEM;
                        goto out;
                }

                natt = x->encap;
                n_type = ext_hdrs[SADB_X_EXT_NAT_T_TYPE-1];
                natt->encap_type = n_type->sadb_x_nat_t_type_type;

                if (ext_hdrs[SADB_X_EXT_NAT_T_SPORT-1]) {
                        const struct sadb_x_nat_t_port *n_port =
                                ext_hdrs[SADB_X_EXT_NAT_T_SPORT-1];
                        natt->encap_sport = n_port->sadb_x_nat_t_port_port;
                }
                if (ext_hdrs[SADB_X_EXT_NAT_T_DPORT-1]) {
                        const struct sadb_x_nat_t_port *n_port =
                                ext_hdrs[SADB_X_EXT_NAT_T_DPORT-1];
                        natt->encap_dport = n_port->sadb_x_nat_t_port_port;
                }
                memset(&natt->encap_oa, 0, sizeof(natt->encap_oa));
        }

        err = xfrm_init_state(x);
        if (err)
                goto out;

        x->km.seq = hdr->sadb_msg_seq;
        return x;

out:
        x->km.state = XFRM_STATE_DEAD;
        xfrm_state_put(x);
        return ERR_PTR(err);
}

static int pfkey_reserved(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        return -EOPNOTSUPP;
}

static int pfkey_getspi(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        struct sk_buff *resp_skb;
        struct sadb_x_sa2 *sa2;
        struct sadb_address *saddr, *daddr;
        struct sadb_msg *out_hdr;
        struct sadb_spirange *range;
        struct xfrm_state *x = NULL;
        int mode;
        int err;
        u32 min_spi, max_spi;
        u32 reqid;
        u8 proto;
        unsigned short family;
        xfrm_address_t *xsaddr = NULL, *xdaddr = NULL;

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

        proto = pfkey_satype2proto(hdr->sadb_msg_satype);
        if (proto == 0)
                return -EINVAL;

        if ((sa2 = ext_hdrs[SADB_X_EXT_SA2-1]) != NULL) {
                mode = pfkey_mode_to_xfrm(sa2->sadb_x_sa2_mode);
                if (mode < 0)
                        return -EINVAL;
                reqid = sa2->sadb_x_sa2_reqid;
        } else {
                mode = 0;
                reqid = 0;
        }

        saddr = ext_hdrs[SADB_EXT_ADDRESS_SRC-1];
        daddr = ext_hdrs[SADB_EXT_ADDRESS_DST-1];

        family = ((struct sockaddr *)(saddr + 1))->sa_family;
        switch (family) {
        case AF_INET:
                xdaddr = (xfrm_address_t *)&((struct sockaddr_in *)(daddr + 1))->sin_addr.s_addr;
                xsaddr = (xfrm_address_t *)&((struct sockaddr_in *)(saddr + 1))->sin_addr.s_addr;
                break;
#if IS_ENABLED(CONFIG_IPV6)
        case AF_INET6:
                xdaddr = (xfrm_address_t *)&((struct sockaddr_in6 *)(daddr + 1))->sin6_addr;
                xsaddr = (xfrm_address_t *)&((struct sockaddr_in6 *)(saddr + 1))->sin6_addr;
                break;
#endif
        }

        if (hdr->sadb_msg_seq) {
                x = xfrm_find_acq_byseq(net, DUMMY_MARK, hdr->sadb_msg_seq);
                if (x && !xfrm_addr_equal(&x->id.daddr, xdaddr, family)) {
                        xfrm_state_put(x);
                        x = NULL;
                }
        }

        if (!x)
                x = xfrm_find_acq(net, &dummy_mark, mode, reqid, 0, proto, xdaddr, xsaddr, 1, family);

        if (x == NULL)
                return -ENOENT;

        min_spi = 0x100;
        max_spi = 0x0fffffff;

        range = ext_hdrs[SADB_EXT_SPIRANGE-1];
        if (range) {
                min_spi = range->sadb_spirange_min;
                max_spi = range->sadb_spirange_max;
        }

        err = verify_spi_info(x->id.proto, min_spi, max_spi);
        if (err) {
                xfrm_state_put(x);
                return err;
        }

        err = xfrm_alloc_spi(x, min_spi, max_spi);
        resp_skb = err ? ERR_PTR(err) : pfkey_xfrm_state2msg(x);

        if (IS_ERR(resp_skb)) {
                xfrm_state_put(x);
                return  PTR_ERR(resp_skb);
        }

        out_hdr = (struct sadb_msg *) resp_skb->data;
        out_hdr->sadb_msg_version = hdr->sadb_msg_version;
        out_hdr->sadb_msg_type = SADB_GETSPI;
        out_hdr->sadb_msg_satype = pfkey_proto2satype(proto);
        out_hdr->sadb_msg_errno = 0;
        out_hdr->sadb_msg_reserved = 0;
        out_hdr->sadb_msg_seq = hdr->sadb_msg_seq;
        out_hdr->sadb_msg_pid = hdr->sadb_msg_pid;

        xfrm_state_put(x);

        pfkey_broadcast(resp_skb, GFP_KERNEL, BROADCAST_ONE, sk, net);

        return 0;
}

static int pfkey_acquire(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        struct xfrm_state *x;

        if (hdr->sadb_msg_len != sizeof(struct sadb_msg)/8)
                return -EOPNOTSUPP;

        if (hdr->sadb_msg_seq == 0 || hdr->sadb_msg_errno == 0)
                return 0;

        x = xfrm_find_acq_byseq(net, DUMMY_MARK, hdr->sadb_msg_seq);
        if (x == NULL)
                return 0;

        spin_lock_bh(&x->lock);
        if (x->km.state == XFRM_STATE_ACQ)
                x->km.state = XFRM_STATE_ERROR;

        spin_unlock_bh(&x->lock);
        xfrm_state_put(x);
        return 0;
}

static inline int event2poltype(int event)
{
        switch (event) {
        case XFRM_MSG_DELPOLICY:
                return SADB_X_SPDDELETE;
        case XFRM_MSG_NEWPOLICY:
                return SADB_X_SPDADD;
        case XFRM_MSG_UPDPOLICY:
                return SADB_X_SPDUPDATE;
        case XFRM_MSG_POLEXPIRE:
        //      return SADB_X_SPDEXPIRE;
        default:
                pr_err("pfkey: Unknown policy event %d\n", event);
                break;
        }

        return 0;
}

static inline int event2keytype(int event)
{
        switch (event) {
        case XFRM_MSG_DELSA:
                return SADB_DELETE;
        case XFRM_MSG_NEWSA:
                return SADB_ADD;
        case XFRM_MSG_UPDSA:
                return SADB_UPDATE;
        case XFRM_MSG_EXPIRE:
                return SADB_EXPIRE;
        default:
                pr_err("pfkey: Unknown SA event %d\n", event);
                break;
        }

        return 0;
}

/* ADD/UPD/DEL */
static int key_notify_sa(struct xfrm_state *x, const struct km_event *c)
{
        struct sk_buff *skb;
        struct sadb_msg *hdr;

        skb = pfkey_xfrm_state2msg(x);

        if (IS_ERR(skb))
                return PTR_ERR(skb);

        hdr = (struct sadb_msg *) skb->data;
        hdr->sadb_msg_version = PF_KEY_V2;
        hdr->sadb_msg_type = event2keytype(c->event);
        hdr->sadb_msg_satype = pfkey_proto2satype(x->id.proto);
        hdr->sadb_msg_errno = 0;
        hdr->sadb_msg_reserved = 0;
        hdr->sadb_msg_seq = c->seq;
        hdr->sadb_msg_pid = c->portid;

        pfkey_broadcast(skb, GFP_ATOMIC, BROADCAST_ALL, NULL, xs_net(x));

        return 0;
}

static int pfkey_add(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        struct xfrm_state *x;
        int err;
        struct km_event c;

        x = pfkey_msg2xfrm_state(net, hdr, ext_hdrs);
        if (IS_ERR(x))
                return PTR_ERR(x);

        xfrm_state_hold(x);
        if (hdr->sadb_msg_type == SADB_ADD)
                err = xfrm_state_add(x);
        else
                err = xfrm_state_update(x);

        xfrm_audit_state_add(x, err ? 0 : 1, true);

        if (err < 0) {
                x->km.state = XFRM_STATE_DEAD;
                __xfrm_state_put(x);
                goto out;
        }

        if (hdr->sadb_msg_type == SADB_ADD)
                c.event = XFRM_MSG_NEWSA;
        else
                c.event = XFRM_MSG_UPDSA;
        c.seq = hdr->sadb_msg_seq;
        c.portid = hdr->sadb_msg_pid;
        km_state_notify(x, &c);
out:
        xfrm_state_put(x);
        return err;
}

static int pfkey_delete(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        struct xfrm_state *x;
        struct km_event c;
        int err;

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

        x = pfkey_xfrm_state_lookup(net, hdr, ext_hdrs);
        if (x == NULL)
                return -ESRCH;

        if ((err = security_xfrm_state_delete(x)))
                goto out;

        if (xfrm_state_kern(x)) {
                err = -EPERM;
                goto out;
        }

        err = xfrm_state_delete(x);

        if (err < 0)
                goto out;

        c.seq = hdr->sadb_msg_seq;
        c.portid = hdr->sadb_msg_pid;
        c.event = XFRM_MSG_DELSA;
        km_state_notify(x, &c);
out:
        xfrm_audit_state_delete(x, err ? 0 : 1, true);
        xfrm_state_put(x);

        return err;
}

static int pfkey_get(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        __u8 proto;
        struct sk_buff *out_skb;
        struct sadb_msg *out_hdr;
        struct xfrm_state *x;

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

        x = pfkey_xfrm_state_lookup(net, hdr, ext_hdrs);
        if (x == NULL)
                return -ESRCH;

        out_skb = pfkey_xfrm_state2msg(x);
        proto = x->id.proto;
        xfrm_state_put(x);
        if (IS_ERR(out_skb))
                return  PTR_ERR(out_skb);

        out_hdr = (struct sadb_msg *) out_skb->data;
        out_hdr->sadb_msg_version = hdr->sadb_msg_version;
        out_hdr->sadb_msg_type = SADB_GET;
        out_hdr->sadb_msg_satype = pfkey_proto2satype(proto);
        out_hdr->sadb_msg_errno = 0;
        out_hdr->sadb_msg_reserved = 0;
        out_hdr->sadb_msg_seq = hdr->sadb_msg_seq;
        out_hdr->sadb_msg_pid = hdr->sadb_msg_pid;
        pfkey_broadcast(out_skb, GFP_ATOMIC, BROADCAST_ONE, sk, sock_net(sk));

        return 0;
}

static struct sk_buff *compose_sadb_supported(const struct sadb_msg *orig,
                                              gfp_t allocation)
{
        struct sk_buff *skb;
        struct sadb_msg *hdr;
        int len, auth_len, enc_len, i;

        auth_len = xfrm_count_pfkey_auth_supported();
        if (auth_len) {
                auth_len *= sizeof(struct sadb_alg);
                auth_len += sizeof(struct sadb_supported);
        }

        enc_len = xfrm_count_pfkey_enc_supported();
        if (enc_len) {
                enc_len *= sizeof(struct sadb_alg);
                enc_len += sizeof(struct sadb_supported);
        }

        len = enc_len + auth_len + sizeof(struct sadb_msg);

        skb = alloc_skb(len + 16, allocation);
        if (!skb)
                goto out_put_algs;

        hdr = skb_put(skb, sizeof(*hdr));
        pfkey_hdr_dup(hdr, orig);
        hdr->sadb_msg_errno = 0;
        hdr->sadb_msg_len = len / sizeof(uint64_t);

        if (auth_len) {
                struct sadb_supported *sp;
                struct sadb_alg *ap;

                sp = skb_put(skb, auth_len);
                ap = (struct sadb_alg *) (sp + 1);

                sp->sadb_supported_len = auth_len / sizeof(uint64_t);
                sp->sadb_supported_exttype = SADB_EXT_SUPPORTED_AUTH;

                for (i = 0; ; i++) {
                        struct xfrm_algo_desc *aalg = xfrm_aalg_get_byidx(i);
                        if (!aalg)
                                break;
                        if (!aalg->pfkey_supported)
                                continue;
                        if (aalg->available)
                                *ap++ = aalg->desc;
                }
        }

        if (enc_len) {
                struct sadb_supported *sp;
                struct sadb_alg *ap;

                sp = skb_put(skb, enc_len);
                ap = (struct sadb_alg *) (sp + 1);

                sp->sadb_supported_len = enc_len / sizeof(uint64_t);
                sp->sadb_supported_exttype = SADB_EXT_SUPPORTED_ENCRYPT;

                for (i = 0; ; i++) {
                        struct xfrm_algo_desc *ealg = xfrm_ealg_get_byidx(i);
                        if (!ealg)
                                break;
                        if (!ealg->pfkey_supported)
                                continue;
                        if (ealg->available)
                                *ap++ = ealg->desc;
                }
        }

out_put_algs:
        return skb;
}

static int pfkey_register(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct pfkey_sock *pfk = pfkey_sk(sk);
        struct sk_buff *supp_skb;

        if (hdr->sadb_msg_satype > SADB_SATYPE_MAX)
                return -EINVAL;

        if (hdr->sadb_msg_satype != SADB_SATYPE_UNSPEC) {
                if (pfk->registered&(1<<hdr->sadb_msg_satype))
                        return -EEXIST;
                pfk->registered |= (1<<hdr->sadb_msg_satype);
        }

        xfrm_probe_algs();

        supp_skb = compose_sadb_supported(hdr, GFP_KERNEL);
        if (!supp_skb) {
                if (hdr->sadb_msg_satype != SADB_SATYPE_UNSPEC)
                        pfk->registered &= ~(1<<hdr->sadb_msg_satype);

                return -ENOBUFS;
        }

        pfkey_broadcast(supp_skb, GFP_KERNEL, BROADCAST_REGISTERED, sk,
                        sock_net(sk));
        return 0;
}

static int unicast_flush_resp(struct sock *sk, const struct sadb_msg *ihdr)
{
        struct sk_buff *skb;
        struct sadb_msg *hdr;

        skb = alloc_skb(sizeof(struct sadb_msg) + 16, GFP_ATOMIC);
        if (!skb)
                return -ENOBUFS;

        hdr = skb_put_data(skb, ihdr, sizeof(struct sadb_msg));
        hdr->sadb_msg_errno = (uint8_t) 0;
        hdr->sadb_msg_len = (sizeof(struct sadb_msg) / sizeof(uint64_t));

        return pfkey_broadcast(skb, GFP_ATOMIC, BROADCAST_ONE, sk,
                               sock_net(sk));
}

static int key_notify_sa_flush(const struct km_event *c)
{
        struct sk_buff *skb;
        struct sadb_msg *hdr;

        skb = alloc_skb(sizeof(struct sadb_msg) + 16, GFP_ATOMIC);
        if (!skb)
                return -ENOBUFS;
        hdr = skb_put(skb, sizeof(struct sadb_msg));
        hdr->sadb_msg_satype = pfkey_proto2satype(c->data.proto);
        hdr->sadb_msg_type = SADB_FLUSH;
        hdr->sadb_msg_seq = c->seq;
        hdr->sadb_msg_pid = c->portid;
        hdr->sadb_msg_version = PF_KEY_V2;
        hdr->sadb_msg_errno = (uint8_t) 0;
        hdr->sadb_msg_len = (sizeof(struct sadb_msg) / sizeof(uint64_t));
        hdr->sadb_msg_reserved = 0;

        pfkey_broadcast(skb, GFP_ATOMIC, BROADCAST_ALL, NULL, c->net);

        return 0;
}

static int pfkey_flush(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        unsigned int proto;
        struct km_event c;
        int err, err2;

        proto = pfkey_satype2proto(hdr->sadb_msg_satype);
        if (proto == 0)
                return -EINVAL;

        err = xfrm_state_flush(net, proto, true, false);
        err2 = unicast_flush_resp(sk, hdr);
        if (err || err2) {
                if (err == -ESRCH) /* empty table - go quietly */
                        err = 0;
                return err ? err : err2;
        }

        c.data.proto = proto;
        c.seq = hdr->sadb_msg_seq;
        c.portid = hdr->sadb_msg_pid;
        c.event = XFRM_MSG_FLUSHSA;
        c.net = net;
        km_state_notify(NULL, &c);

        return 0;
}

static int dump_sa(struct xfrm_state *x, int count, void *ptr)
{
        struct pfkey_sock *pfk = ptr;
        struct sk_buff *out_skb;
        struct sadb_msg *out_hdr;

        if (!pfkey_can_dump(&pfk->sk))
                return -ENOBUFS;

        out_skb = pfkey_xfrm_state2msg(x);
        if (IS_ERR(out_skb))
                return PTR_ERR(out_skb);

        out_hdr = (struct sadb_msg *) out_skb->data;
        out_hdr->sadb_msg_version = pfk->dump.msg_version;
        out_hdr->sadb_msg_type = SADB_DUMP;
        out_hdr->sadb_msg_satype = pfkey_proto2satype(x->id.proto);
        out_hdr->sadb_msg_errno = 0;
        out_hdr->sadb_msg_reserved = 0;
        out_hdr->sadb_msg_seq = count + 1;
        out_hdr->sadb_msg_pid = pfk->dump.msg_portid;

        if (pfk->dump.skb)
                pfkey_broadcast(pfk->dump.skb, GFP_ATOMIC, BROADCAST_ONE,
                                &pfk->sk, sock_net(&pfk->sk));
        pfk->dump.skb = out_skb;

        return 0;
}

static int pfkey_dump_sa(struct pfkey_sock *pfk)
{
        struct net *net = sock_net(&pfk->sk);
        return xfrm_state_walk(net, &pfk->dump.u.state, dump_sa, (void *) pfk);
}

static void pfkey_dump_sa_done(struct pfkey_sock *pfk)
{
        struct net *net = sock_net(&pfk->sk);

        xfrm_state_walk_done(&pfk->dump.u.state, net);
}

static int pfkey_dump(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        u8 proto;
        struct xfrm_address_filter *filter = NULL;
        struct pfkey_sock *pfk = pfkey_sk(sk);

        mutex_lock(&pfk->dump_lock);
        if (pfk->dump.dump != NULL) {
                mutex_unlock(&pfk->dump_lock);
                return -EBUSY;
        }

        proto = pfkey_satype2proto(hdr->sadb_msg_satype);
        if (proto == 0) {
                mutex_unlock(&pfk->dump_lock);
                return -EINVAL;
        }

        if (ext_hdrs[SADB_X_EXT_FILTER - 1]) {
                struct sadb_x_filter *xfilter = ext_hdrs[SADB_X_EXT_FILTER - 1];

                if ((xfilter->sadb_x_filter_splen >=
                        (sizeof(xfrm_address_t) << 3)) ||
                    (xfilter->sadb_x_filter_dplen >=
                        (sizeof(xfrm_address_t) << 3))) {
                        mutex_unlock(&pfk->dump_lock);
                        return -EINVAL;
                }
                filter = kmalloc(sizeof(*filter), GFP_KERNEL);
                if (filter == NULL) {
                        mutex_unlock(&pfk->dump_lock);
                        return -ENOMEM;
                }

                memcpy(&filter->saddr, &xfilter->sadb_x_filter_saddr,
                       sizeof(xfrm_address_t));
                memcpy(&filter->daddr, &xfilter->sadb_x_filter_daddr,
                       sizeof(xfrm_address_t));
                filter->family = xfilter->sadb_x_filter_family;
                filter->splen = xfilter->sadb_x_filter_splen;
                filter->dplen = xfilter->sadb_x_filter_dplen;
        }

        pfk->dump.msg_version = hdr->sadb_msg_version;
        pfk->dump.msg_portid = hdr->sadb_msg_pid;
        pfk->dump.dump = pfkey_dump_sa;
        pfk->dump.done = pfkey_dump_sa_done;
        xfrm_state_walk_init(&pfk->dump.u.state, proto, filter);
        mutex_unlock(&pfk->dump_lock);

        return pfkey_do_dump(pfk);
}

static int pfkey_promisc(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct pfkey_sock *pfk = pfkey_sk(sk);
        int satype = hdr->sadb_msg_satype;
        bool reset_errno = false;

        if (hdr->sadb_msg_len == (sizeof(*hdr) / sizeof(uint64_t))) {
                reset_errno = true;
                if (satype != 0 && satype != 1)
                        return -EINVAL;
                pfk->promisc = satype;
        }
        if (reset_errno && skb_cloned(skb))
                skb = skb_copy(skb, GFP_KERNEL);
        else
                skb = skb_clone(skb, GFP_KERNEL);

        if (reset_errno && skb) {
                struct sadb_msg *new_hdr = (struct sadb_msg *) skb->data;
                new_hdr->sadb_msg_errno = 0;
        }

        pfkey_broadcast(skb, GFP_KERNEL, BROADCAST_ALL, NULL, sock_net(sk));
        return 0;
}

static int check_reqid(struct xfrm_policy *xp, int dir, int count, void *ptr)
{
        int i;
        u32 reqid = *(u32*)ptr;

        for (i=0; i<xp->xfrm_nr; i++) {
                if (xp->xfrm_vec[i].reqid == reqid)
                        return -EEXIST;
        }
        return 0;
}

static u32 gen_reqid(struct net *net)
{
        struct xfrm_policy_walk walk;
        u32 start;
        int rc;
        static u32 reqid = IPSEC_MANUAL_REQID_MAX;

        start = reqid;
        do {
                ++reqid;
                if (reqid == 0)
                        reqid = IPSEC_MANUAL_REQID_MAX+1;
                xfrm_policy_walk_init(&walk, XFRM_POLICY_TYPE_MAIN);
                rc = xfrm_policy_walk(net, &walk, check_reqid, (void*)&reqid);
                xfrm_policy_walk_done(&walk, net);
                if (rc != -EEXIST)
                        return reqid;
        } while (reqid != start);
        return 0;
}

static int
parse_ipsecrequest(struct xfrm_policy *xp, struct sadb_x_ipsecrequest *rq)
{
        struct net *net = xp_net(xp);
        struct xfrm_tmpl *t = xp->xfrm_vec + xp->xfrm_nr;
        int mode;

        if (xp->xfrm_nr >= XFRM_MAX_DEPTH)
                return -ELOOP;

        if (rq->sadb_x_ipsecrequest_mode == 0)
                return -EINVAL;
        if (!xfrm_id_proto_valid(rq->sadb_x_ipsecrequest_proto))
                return -EINVAL;

        t->id.proto = rq->sadb_x_ipsecrequest_proto;
        if ((mode = pfkey_mode_to_xfrm(rq->sadb_x_ipsecrequest_mode)) < 0)
                return -EINVAL;
        t->mode = mode;
        if (rq->sadb_x_ipsecrequest_level == IPSEC_LEVEL_USE)
                t->optional = 1;
        else if (rq->sadb_x_ipsecrequest_level == IPSEC_LEVEL_UNIQUE) {
                t->reqid = rq->sadb_x_ipsecrequest_reqid;
                if (t->reqid > IPSEC_MANUAL_REQID_MAX)
                        t->reqid = 0;
                if (!t->reqid && !(t->reqid = gen_reqid(net)))
                        return -ENOBUFS;
        }

        /* addresses present only in tunnel mode */
        if (t->mode == XFRM_MODE_TUNNEL) {
                int err;

                err = parse_sockaddr_pair(
                        (struct sockaddr *)(rq + 1),
                        rq->sadb_x_ipsecrequest_len - sizeof(*rq),
                        &t->saddr, &t->id.daddr, &t->encap_family);
                if (err)
                        return err;
        } else
                t->encap_family = xp->family;

        /* No way to set this via kame pfkey */
        t->allalgs = 1;
        xp->xfrm_nr++;
        return 0;
}

static int
parse_ipsecrequests(struct xfrm_policy *xp, struct sadb_x_policy *pol)
{
        int err;
        int len = pol->sadb_x_policy_len*8 - sizeof(struct sadb_x_policy);
        struct sadb_x_ipsecrequest *rq = (void*)(pol+1);

        if (pol->sadb_x_policy_len * 8 < sizeof(struct sadb_x_policy))
                return -EINVAL;

        while (len >= sizeof(*rq)) {
                if (len < rq->sadb_x_ipsecrequest_len ||
                    rq->sadb_x_ipsecrequest_len < sizeof(*rq))
                        return -EINVAL;

                if ((err = parse_ipsecrequest(xp, rq)) < 0)
                        return err;
                len -= rq->sadb_x_ipsecrequest_len;
                rq = (void*)((u8*)rq + rq->sadb_x_ipsecrequest_len);
        }
        return 0;
}

static inline int pfkey_xfrm_policy2sec_ctx_size(const struct xfrm_policy *xp)
{
        struct xfrm_sec_ctx *xfrm_ctx = xp->security;

        if (xfrm_ctx) {
                int len = sizeof(struct sadb_x_sec_ctx);
                len += xfrm_ctx->ctx_len;
                return PFKEY_ALIGN8(len);
        }
        return 0;
}

static int pfkey_xfrm_policy2msg_size(const struct xfrm_policy *xp)
{
        const struct xfrm_tmpl *t;
        int sockaddr_size = pfkey_sockaddr_size(xp->family);
        int socklen = 0;
        int i;

        for (i=0; i<xp->xfrm_nr; i++) {
                t = xp->xfrm_vec + i;
                socklen += pfkey_sockaddr_len(t->encap_family);
        }

        return sizeof(struct sadb_msg) +
                (sizeof(struct sadb_lifetime) * 3) +
                (sizeof(struct sadb_address) * 2) +
                (sockaddr_size * 2) +
                sizeof(struct sadb_x_policy) +
                (xp->xfrm_nr * sizeof(struct sadb_x_ipsecrequest)) +
                (socklen * 2) +
                pfkey_xfrm_policy2sec_ctx_size(xp);
}

static struct sk_buff * pfkey_xfrm_policy2msg_prep(const struct xfrm_policy *xp)
{
        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, const struct xfrm_policy *xp, int dir)
{
        struct sadb_msg *hdr;
        struct sadb_address *addr;
        struct sadb_lifetime *lifetime;
        struct sadb_x_policy *pol;
        struct sadb_x_sec_ctx *sec_ctx;
        struct xfrm_sec_ctx *xfrm_ctx;
        int i;
        int size;
        int sockaddr_size = pfkey_sockaddr_size(xp->family);
        int socklen = pfkey_sockaddr_len(xp->family);

        size = pfkey_xfrm_policy2msg_size(xp);

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

        /* src address */
        addr = 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;
        if (!pfkey_sockaddr_fill(&xp->selector.saddr,
                                 xp->selector.sport,
                                 (struct sockaddr *) (addr + 1),
                                 xp->family))
                BUG();

        /* dst address */
        addr = 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;

        pfkey_sockaddr_fill(&xp->selector.daddr, xp->selector.dport,
                            (struct sockaddr *) (addr + 1),
                            xp->family);

        /* hard time */
        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 = 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 = 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 = 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_reserved = 0;
        pol->sadb_x_policy_id = xp->index;
        pol->sadb_x_policy_priority = xp->priority;

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

                req_size = sizeof(struct sadb_x_ipsecrequest);
                if (t->mode == XFRM_MODE_TUNNEL) {
                        socklen = pfkey_sockaddr_len(t->encap_family);
                        req_size += socklen * 2;
                } else {
                        size -= 2*socklen;
                }
                rq = 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) {
                        u8 *sa = (void *)(rq + 1);
                        pfkey_sockaddr_fill(&t->saddr, 0,
                                            (struct sockaddr *)sa,
                                            t->encap_family);
                        pfkey_sockaddr_fill(&t->id.daddr, 0,
                                            (struct sockaddr *) (sa + socklen),
                                            t->encap_family);
                }
        }

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

                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 = refcount_read(&xp->refcnt);

        return 0;
}

static int key_notify_policy(struct xfrm_policy *xp, int dir, const 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))
                return PTR_ERR(out_skb);

        err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
        if (err < 0) {
                kfree_skb(out_skb);
                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->portid;
        pfkey_broadcast(out_skb, GFP_ATOMIC, BROADCAST_ALL, NULL, xp_net(xp));
        return 0;

}

static int pfkey_spdadd(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        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(net, 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);
        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 = 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, GFP_KERNEL);

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

                err = security_xfrm_policy_alloc(&xp->security, uctx, GFP_KERNEL);
                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, true);

        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.portid = hdr->sadb_msg_pid;

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

out:
        xp->walk.dead = 1;
        xfrm_policy_destroy(xp);
        return err;
}

static int pfkey_spddelete(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        int err;
        struct sadb_address *sa;
        struct sadb_x_policy *pol;
        struct xfrm_policy *xp;
        struct xfrm_selector sel;
        struct km_event c;
        struct sadb_x_sec_ctx *sec_ctx;
        struct xfrm_sec_ctx *pol_ctx = NULL;

        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 = 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, GFP_KERNEL);

                if (!uctx)
                        return -ENOMEM;

                err = security_xfrm_policy_alloc(&pol_ctx, uctx, GFP_KERNEL);
                kfree(uctx);
                if (err)
                        return err;
        }

        xp = xfrm_policy_bysel_ctx(net, &dummy_mark, 0, XFRM_POLICY_TYPE_MAIN,
                                   pol->sadb_x_policy_dir - 1, &sel, pol_ctx,
                                   1, &err);
        security_xfrm_policy_free(pol_ctx);
        if (xp == NULL)
                return -ENOENT;

        xfrm_audit_policy_delete(xp, err ? 0 : 1, true);

        if (err)
                goto out;

        c.seq = hdr->sadb_msg_seq;
        c.portid = hdr->sadb_msg_pid;
        c.data.byid = 0;
        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, const 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) {
                kfree_skb(out_skb);
                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_satype = 0;
        out_hdr->sadb_msg_errno = 0;
        out_hdr->sadb_msg_seq = hdr->sadb_msg_seq;
        out_hdr->sadb_msg_pid = hdr->sadb_msg_pid;
        pfkey_broadcast(out_skb, GFP_ATOMIC, BROADCAST_ONE, sk, xp_net(xp));
        err = 0;

out:
        return err;
}

static int pfkey_sockaddr_pair_size(sa_family_t family)
{
        return PFKEY_ALIGN8(pfkey_sockaddr_len(family) * 2);
}

static int parse_sockaddr_pair(struct sockaddr *sa, int ext_len,
                               xfrm_address_t *saddr, xfrm_address_t *daddr,
                               u16 *family)
{
        int af, socklen;

        if (ext_len < 2 || ext_len < pfkey_sockaddr_pair_size(sa->sa_family))
                return -EINVAL;

        af = pfkey_sockaddr_extract(sa, saddr);
        if (!af)
                return -EINVAL;

        socklen = pfkey_sockaddr_len(af);
        if (pfkey_sockaddr_extract((struct sockaddr *) (((u8 *)sa) + socklen),
                                   daddr) != af)
                return -EINVAL;

        *family = af;
        return 0;
}

#ifdef CONFIG_NET_KEY_MIGRATE
static int ipsecrequests_to_migrate(struct sadb_x_ipsecrequest *rq1, int len,
                                    struct xfrm_migrate *m)
{
        int err;
        struct sadb_x_ipsecrequest *rq2;
        int mode;

        if (len < sizeof(*rq1) ||
            len < rq1->sadb_x_ipsecrequest_len ||
            rq1->sadb_x_ipsecrequest_len < sizeof(*rq1))
                return -EINVAL;

        /* old endoints */
        err = parse_sockaddr_pair((struct sockaddr *)(rq1 + 1),
                                  rq1->sadb_x_ipsecrequest_len - sizeof(*rq1),
                                  &m->old_saddr, &m->old_daddr,
                                  &m->old_family);
        if (err)
                return err;

        rq2 = (struct sadb_x_ipsecrequest *)((u8 *)rq1 + rq1->sadb_x_ipsecrequest_len);
        len -= rq1->sadb_x_ipsecrequest_len;

        if (len <= sizeof(*rq2) ||
            len < rq2->sadb_x_ipsecrequest_len ||
            rq2->sadb_x_ipsecrequest_len < sizeof(*rq2))
                return -EINVAL;

        /* new endpoints */
        err = parse_sockaddr_pair((struct sockaddr *)(rq2 + 1),
                                  rq2->sadb_x_ipsecrequest_len - sizeof(*rq2),
                                  &m->new_saddr, &m->new_daddr,
                                  &m->new_family);
        if (err)
                return err;

        if (rq1->sadb_x_ipsecrequest_proto != rq2->sadb_x_ipsecrequest_proto ||
            rq1->sadb_x_ipsecrequest_mode != rq2->sadb_x_ipsecrequest_mode ||
            rq1->sadb_x_ipsecrequest_reqid != rq2->sadb_x_ipsecrequest_reqid)
                return -EINVAL;

        m->proto = rq1->sadb_x_ipsecrequest_proto;
        if ((mode = pfkey_mode_to_xfrm(rq1->sadb_x_ipsecrequest_mode)) < 0)
                return -EINVAL;
        m->mode = mode;
        m->reqid = rq1->sadb_x_ipsecrequest_reqid;

        return ((int)(rq1->sadb_x_ipsecrequest_len +
                      rq2->sadb_x_ipsecrequest_len));
}

static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
                         const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        int i, len, ret, err = -EINVAL;
        u8 dir;
        struct sadb_address *sa;
        struct sadb_x_kmaddress *kma;
        struct sadb_x_policy *pol;
        struct sadb_x_ipsecrequest *rq;
        struct xfrm_selector sel;
        struct xfrm_migrate m[XFRM_MAX_DEPTH];
        struct xfrm_kmaddress k;
        struct net *net = sock_net(sk);

        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]) {
                err = -EINVAL;
                goto out;
        }

        kma = ext_hdrs[SADB_X_EXT_KMADDRESS - 1];
        pol = ext_hdrs[SADB_X_EXT_POLICY - 1];

        if (pol->sadb_x_policy_dir >= IPSEC_DIR_MAX) {
                err = -EINVAL;
                goto out;
        }

        if (kma) {
                /* convert sadb_x_kmaddress to xfrm_kmaddress */
                k.reserved = kma->sadb_x_kmaddress_reserved;
                ret = parse_sockaddr_pair((struct sockaddr *)(kma + 1),
                                          8*(kma->sadb_x_kmaddress_len) - sizeof(*kma),
                                          &k.local, &k.remote, &k.family);
                if (ret < 0) {
                        err = ret;
                        goto out;
                }
        }

        dir = pol->sadb_x_policy_dir - 1;
        memset(&sel, 0, sizeof(sel));

        /* set source address info of selector */
        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);

        /* set destination address info of selector */
        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);

        rq = (struct sadb_x_ipsecrequest *)(pol + 1);

        /* extract ipsecrequests */
        i = 0;
        len = pol->sadb_x_policy_len * 8 - sizeof(struct sadb_x_policy);

        while (len > 0 && i < XFRM_MAX_DEPTH) {
                ret = ipsecrequests_to_migrate(rq, len, &m[i]);
                if (ret < 0) {
                        err = ret;
                        goto out;
                } else {
                        rq = (struct sadb_x_ipsecrequest *)((u8 *)rq + ret);
                        len -= ret;
                        i++;
                }
        }

        if (!i || len > 0) {
                err = -EINVAL;
                goto out;
        }

        return xfrm_migrate(&sel, dir, XFRM_POLICY_TYPE_MAIN, m, i,
                            kma ? &k : NULL, net, NULL);

 out:
        return err;
}
#else
static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
                         const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        return -ENOPROTOOPT;
}
#endif


static int pfkey_spdget(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        unsigned int dir;
        int err = 0, delete;
        struct sadb_x_policy *pol;
        struct xfrm_policy *xp;
        struct km_event c;

        if ((pol = ext_hdrs[SADB_X_EXT_POLICY-1]) == NULL)
                return -EINVAL;

        dir = xfrm_policy_id2dir(pol->sadb_x_policy_id);
        if (dir >= XFRM_POLICY_MAX)
                return -EINVAL;

        delete = (hdr->sadb_msg_type == SADB_X_SPDDELETE2);
        xp = xfrm_policy_byid(net, &dummy_mark, 0, XFRM_POLICY_TYPE_MAIN,
                              dir, pol->sadb_x_policy_id, delete, &err);
        if (xp == NULL)
                return -ENOENT;

        if (delete) {
                xfrm_audit_policy_delete(xp, err ? 0 : 1, true);

                if (err)
                        goto out;
                c.seq = hdr->sadb_msg_seq;
                c.portid = hdr->sadb_msg_pid;
                c.data.byid = 1;
                c.event = XFRM_MSG_DELPOLICY;
                km_policy_notify(xp, dir, &c);
        } else {
                err = key_pol_get_resp(sk, xp, hdr, dir);
        }

out:
        xfrm_pol_put(xp);
        return err;
}

static int dump_sp(struct xfrm_policy *xp, int dir, int count, void *ptr)
{
        struct pfkey_sock *pfk = ptr;
        struct sk_buff *out_skb;
        struct sadb_msg *out_hdr;
        int err;

        if (!pfkey_can_dump(&pfk->sk))
                return -ENOBUFS;

        out_skb = pfkey_xfrm_policy2msg_prep(xp);
        if (IS_ERR(out_skb))
                return PTR_ERR(out_skb);

        err = pfkey_xfrm_policy2msg(out_skb, xp, dir);
        if (err < 0) {
                kfree_skb(out_skb);
                return err;
        }

        out_hdr = (struct sadb_msg *) out_skb->data;
        out_hdr->sadb_msg_version = pfk->dump.msg_version;
        out_hdr->sadb_msg_type = SADB_X_SPDDUMP;
        out_hdr->sadb_msg_satype = SADB_SATYPE_UNSPEC;
        out_hdr->sadb_msg_errno = 0;
        out_hdr->sadb_msg_seq = count + 1;
        out_hdr->sadb_msg_pid = pfk->dump.msg_portid;

        if (pfk->dump.skb)
                pfkey_broadcast(pfk->dump.skb, GFP_ATOMIC, BROADCAST_ONE,
                                &pfk->sk, sock_net(&pfk->sk));
        pfk->dump.skb = out_skb;

        return 0;
}

static int pfkey_dump_sp(struct pfkey_sock *pfk)
{
        struct net *net = sock_net(&pfk->sk);
        return xfrm_policy_walk(net, &pfk->dump.u.policy, dump_sp, (void *) pfk);
}

static void pfkey_dump_sp_done(struct pfkey_sock *pfk)
{
        struct net *net = sock_net((struct sock *)pfk);

        xfrm_policy_walk_done(&pfk->dump.u.policy, net);
}

static int pfkey_spddump(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct pfkey_sock *pfk = pfkey_sk(sk);

        mutex_lock(&pfk->dump_lock);
        if (pfk->dump.dump != NULL) {
                mutex_unlock(&pfk->dump_lock);
                return -EBUSY;
        }

        pfk->dump.msg_version = hdr->sadb_msg_version;
        pfk->dump.msg_portid = hdr->sadb_msg_pid;
        pfk->dump.dump = pfkey_dump_sp;
        pfk->dump.done = pfkey_dump_sp_done;
        xfrm_policy_walk_init(&pfk->dump.u.policy, XFRM_POLICY_TYPE_MAIN);
        mutex_unlock(&pfk->dump_lock);

        return pfkey_do_dump(pfk);
}

static int key_notify_policy_flush(const struct km_event *c)
{
        struct sk_buff *skb_out;
        struct sadb_msg *hdr;

        skb_out = alloc_skb(sizeof(struct sadb_msg) + 16, GFP_ATOMIC);
        if (!skb_out)
                return -ENOBUFS;
        hdr = skb_put(skb_out, sizeof(struct sadb_msg));
        hdr->sadb_msg_type = SADB_X_SPDFLUSH;
        hdr->sadb_msg_seq = c->seq;
        hdr->sadb_msg_pid = c->portid;
        hdr->sadb_msg_version = PF_KEY_V2;
        hdr->sadb_msg_errno = (uint8_t) 0;
        hdr->sadb_msg_satype = SADB_SATYPE_UNSPEC;
        hdr->sadb_msg_len = (sizeof(struct sadb_msg) / sizeof(uint64_t));
        hdr->sadb_msg_reserved = 0;
        pfkey_broadcast(skb_out, GFP_ATOMIC, BROADCAST_ALL, NULL, c->net);
        return 0;

}

static int pfkey_spdflush(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
        struct net *net = sock_net(sk);
        struct km_event c;
        int err, err2;

        err = xfrm_policy_flush(net, XFRM_POLICY_TYPE_MAIN, true);
        err2 = unicast_flush_resp(sk, hdr);
        if (err || err2) {
                if (err == -ESRCH) /* empty table - old silent behavior */
                        return 0;
                return err;
        }

        c.data.type = XFRM_POLICY_TYPE_MAIN;
        c.event = XFRM_MSG_FLUSHPOLICY;
        c.portid = hdr->sadb_msg_pid;
        c.seq = hdr->sadb_msg_seq;
        c.net = net;
        km_policy_notify(NULL, 0, &c);

        return 0;
}

typedef int (*pfkey_handler)(struct sock *sk, struct sk_buff *skb,
                             const struct sadb_msg *hdr, void * const *ext_hdrs);
static const pfkey_handler pfkey_funcs[SADB_MAX + 1] = {
        [SADB_RESERVED]         = pfkey_reserved,
        [SADB_GETSPI]           = pfkey_getspi,
        [SADB_UPDATE]           = pfkey_add,
        [SADB_ADD]              = pfkey_add,
        [SADB_DELETE]           = pfkey_delete,
        [SADB_GET]              = pfkey_get,
        [SADB_ACQUIRE]          = pfkey_acquire,
        [SADB_REGISTER]         = pfkey_register,
        [SADB_EXPIRE]           = NULL,
        [SADB_FLUSH]            = pfkey_flush,
        [SADB_DUMP]             = pfkey_dump,
        [SADB_X_PROMISC]        = pfkey_promisc,
        [SADB_X_PCHANGE]        = NULL,
        [SADB_X_SPDUPDATE]      = pfkey_spdadd,
        [SADB_X_SPDADD]         = pfkey_spdadd,
        [SADB_X_SPDDELETE]      = pfkey_spddelete,
        [SADB_X_SPDGET]         = pfkey_spdget,
        [SADB_X_SPDACQUIRE]     = NULL,
        [SADB_X_SPDDUMP]        = pfkey_spddump,
        [SADB_X_SPDFLUSH]       = pfkey_spdflush,
        [SADB_X_SPDSETIDX]      = pfkey_spdadd,
        [SADB_X_SPDDELETE2]     = pfkey_spdget,
        [SADB_X_MIGRATE]        = pfkey_migrate,
};

static int pfkey_process(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr)
{
        void *ext_hdrs[SADB_EXT_MAX];
        int err;

        pfkey_broadcast(skb_clone(skb, GFP_KERNEL), GFP_KERNEL,
                        BROADCAST_PROMISC_ONLY, NULL, sock_net(sk));

        memset(ext_hdrs, 0, sizeof(ext_hdrs));
        err = parse_exthdrs(skb, hdr, ext_hdrs);
        if (!err) {
                err = -EOPNOTSUPP;
                if (pfkey_funcs[hdr->sadb_msg_type])
                        err = pfkey_funcs[hdr->sadb_msg_type](sk, skb, hdr, ext_hdrs);
        }
        return err;
}

static struct sadb_msg *pfkey_get_base_msg(struct sk_buff *skb, int *errp)
{
        struct sadb_msg *hdr = NULL;

        if (skb->len < sizeof(*hdr)) {
                *errp = -EMSGSIZE;
        } else {
                hdr = (struct sadb_msg *) skb->data;
                if (hdr->sadb_msg_version != PF_KEY_V2 ||
                    hdr->sadb_msg_reserved != 0 ||
                    (hdr->sadb_msg_type <= SADB_RESERVED ||
                     hdr->sadb_msg_type > SADB_MAX)) {
                        hdr = NULL;
                        *errp = -EINVAL;
                } else if (hdr->sadb_msg_len != (skb->len /
                                                 sizeof(uint64_t)) ||
                           hdr->sadb_msg_len < (sizeof(struct sadb_msg) /
                                                sizeof(uint64_t))) {
                        hdr = NULL;
                        *errp = -EMSGSIZE;
                } else {
                        *errp = 0;
                }
        }
        return hdr;
}

static inline int aalg_tmpl_set(const struct xfrm_tmpl *t,
                                const struct xfrm_algo_desc *d)
{
        unsigned int id = d->desc.sadb_alg_id;

        if (id >= sizeof(t->aalgos) * 8)
                return 0;

        return (t->aalgos >> id) & 1;
}

static inline int ealg_tmpl_set(const struct xfrm_tmpl *t,
                                const struct xfrm_algo_desc *d)
{
        unsigned int id = d->desc.sadb_alg_id;

        if (id >= sizeof(t->ealgos) * 8)
                return 0;

        return (t->ealgos >> id) & 1;
}

static int count_ah_combs(const struct xfrm_tmpl *t)
{
        int i, sz = 0;

        for (i = 0; ; i++) {
                const struct xfrm_algo_desc *aalg = xfrm_aalg_get_byidx(i);
                if (!aalg)
                        break;
                if (!aalg->pfkey_supported)
                        continue;
                if (aalg_tmpl_set(t, aalg) && aalg->available)
                        sz += sizeof(struct sadb_comb);
        }
        return sz + sizeof(struct sadb_prop);
}

static int count_esp_combs(const struct xfrm_tmpl *t)
{
        int i, k, sz = 0;

        for (i = 0; ; i++) {
                const struct xfrm_algo_desc *ealg = xfrm_ealg_get_byidx(i);
                if (!ealg)
                        break;

                if (!ealg->pfkey_supported)
                        continue;

                if (!(ealg_tmpl_set(t, ealg) && ealg->available))
                        continue;

                for (k = 1; ; k++) {
                        const struct xfrm_algo_desc *aalg = xfrm_aalg_get_byidx(k);
                        if (!aalg)
                                break;

                        if (!aalg->pfkey_supported)
                                continue;

                        if (aalg_tmpl_set(t, aalg) && aalg->available)
                                sz += sizeof(struct sadb_comb);
                }
        }
        return sz + sizeof(struct sadb_prop);
}

static void dump_ah_combs(struct sk_buff *skb, const struct xfrm_tmpl *t)
{
        struct sadb_prop *p;
        int i;

        p = skb_put(skb, sizeof(struct sadb_prop));
        p->sadb_prop_len = sizeof(struct sadb_prop)/8;
        p->sadb_prop_exttype = SADB_EXT_PROPOSAL;
        p->sadb_prop_replay = 32;
        memset(p->sadb_prop_reserved, 0, sizeof(p->sadb_prop_reserved));

        for (i = 0; ; i++) {
                const struct xfrm_algo_desc *aalg = xfrm_aalg_get_byidx(i);
                if (!aalg)
                        break;

                if (!aalg->pfkey_supported)
                        continue;

                if (aalg_tmpl_set(t, aalg) && aalg->available) {
                        struct sadb_comb *c;
                        c = skb_put_zero(skb, sizeof(struct sadb_comb));
                        p->sadb_prop_len += sizeof(struct sadb_comb)/8;
                        c->sadb_comb_auth = aalg->desc.sadb_alg_id;
                        c->sadb_comb_auth_minbits = aalg->desc.sadb_alg_minbits;
                        c->sadb_comb_auth_maxbits = aalg->desc.sadb_alg_maxbits;
                        c->sadb_comb_hard_addtime = 24*60*60;
                        c->sadb_comb_soft_addtime = 20*60*60;
                        c->sadb_comb_hard_usetime = 8*60*60;
                        c->sadb_comb_soft_usetime = 7*60*60;
                }
        }
}

static void dump_esp_combs(struct sk_buff *skb, const struct xfrm_tmpl *t)
{
        struct sadb_prop *p;
        int i, k;

        p = skb_put(skb, sizeof(struct sadb_prop));
        p->sadb_prop_len = sizeof(struct sadb_prop)/8;
        p->sadb_prop_exttype = SADB_EXT_PROPOSAL;
        p->sadb_prop_replay = 32;
        memset(p->sadb_prop_reserved, 0, sizeof(p->sadb_prop_reserved));

        for (i=0; ; i++) {
                const struct xfrm_algo_desc *ealg = xfrm_ealg_get_byidx(i);
                if (!ealg)
                        break;

                if (!ealg->pfkey_supported)
                        continue;

                if (!(ealg_tmpl_set(t, ealg) && ealg->available))
                        continue;

                for (k = 1; ; k++) {
                        struct sadb_comb *c;
                        const struct xfrm_algo_desc *aalg = xfrm_aalg_get_byidx(k);
                        if (!aalg)