/* xfrm_user.c: User interface to configure xfrm engine.
 *
 * Copyright (C) 2002 David S. Miller (davem@redhat.com)
 *
 * Changes:
 *      Mitsuru KANDA @USAGI
 *      Kazunori MIYAZAWA @USAGI
 *      Kunihiro Ishiguro <kunihiro@ipinfusion.com>
 *              IPv6 support
 *
 */

#include <linux/crypto.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/pfkeyv2.h>
#include <linux/ipsec.h>
#include <linux/init.h>
#include <linux/security.h>
#include <net/sock.h>
#include <net/xfrm.h>
#include <net/netlink.h>
#include <net/ah.h>
#include <linux/uaccess.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <linux/in6.h>
#endif
#include <asm/unaligned.h>

static int verify_one_alg(struct nlattr **attrs, enum xfrm_attr_type_t type)
{
        struct nlattr *rt = attrs[type];
        struct xfrm_algo *algp;

        if (!rt)
                return 0;

        algp = nla_data(rt);
        if (nla_len(rt) < (int)xfrm_alg_len(algp))
                return -EINVAL;

        switch (type) {
        case XFRMA_ALG_AUTH:
        case XFRMA_ALG_CRYPT:
        case XFRMA_ALG_COMP:
                break;

        default:
                return -EINVAL;
        }

        algp->alg_name[sizeof(algp->alg_name) - 1] = '\0';
        return 0;
}

static int verify_auth_trunc(struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_ALG_AUTH_TRUNC];
        struct xfrm_algo_auth *algp;

        if (!rt)
                return 0;

        algp = nla_data(rt);
        if (nla_len(rt) < (int)xfrm_alg_auth_len(algp))
                return -EINVAL;

        algp->alg_name[sizeof(algp->alg_name) - 1] = '\0';
        return 0;
}

static int verify_aead(struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_ALG_AEAD];
        struct xfrm_algo_aead *algp;

        if (!rt)
                return 0;

        algp = nla_data(rt);
        if (nla_len(rt) < (int)aead_len(algp))
                return -EINVAL;

        algp->alg_name[sizeof(algp->alg_name) - 1] = '\0';
        return 0;
}

static void verify_one_addr(struct nlattr **attrs, enum xfrm_attr_type_t type,
                           xfrm_address_t **addrp)
{
        struct nlattr *rt = attrs[type];

        if (rt && addrp)
                *addrp = nla_data(rt);
}

static inline int verify_sec_ctx_len(struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_SEC_CTX];
        struct xfrm_user_sec_ctx *uctx;

        if (!rt)
                return 0;

        uctx = nla_data(rt);
        if (uctx->len > nla_len(rt) ||
            uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len))
                return -EINVAL;

        return 0;
}

static inline int verify_replay(struct xfrm_usersa_info *p,
                                struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_REPLAY_ESN_VAL];
        struct xfrm_replay_state_esn *rs;

        if (!rt)
                return (p->flags & XFRM_STATE_ESN) ? -EINVAL : 0;

        rs = nla_data(rt);

        if (rs->bmp_len > XFRMA_REPLAY_ESN_MAX / sizeof(rs->bmp[0]) / 8)
                return -EINVAL;

        if (nla_len(rt) < (int)xfrm_replay_state_esn_len(rs) &&
            nla_len(rt) != sizeof(*rs))
                return -EINVAL;

        /* As only ESP and AH support ESN feature. */
        if ((p->id.proto != IPPROTO_ESP) && (p->id.proto != IPPROTO_AH))
                return -EINVAL;

        if (p->replay_window != 0)
                return -EINVAL;

        return 0;
}

static int verify_newsa_info(struct xfrm_usersa_info *p,
                             struct nlattr **attrs)
{
        int err;

        err = -EINVAL;
        switch (p->family) {
        case AF_INET:
                break;

        case AF_INET6:
#if IS_ENABLED(CONFIG_IPV6)
                break;
#else
                err = -EAFNOSUPPORT;
                goto out;
#endif

        default:
                goto out;
        }

        switch (p->sel.family) {
        case AF_UNSPEC:
                break;

        case AF_INET:
                if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
                        goto out;

                break;

        case AF_INET6:
#if IS_ENABLED(CONFIG_IPV6)
                if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
                        goto out;

                break;
#else
                err = -EAFNOSUPPORT;
                goto out;
#endif

        default:
                goto out;
        }

        err = -EINVAL;
        switch (p->id.proto) {
        case IPPROTO_AH:
                if ((!attrs[XFRMA_ALG_AUTH]     &&
                     !attrs[XFRMA_ALG_AUTH_TRUNC]) ||
                    attrs[XFRMA_ALG_AEAD]       ||
                    attrs[XFRMA_ALG_CRYPT]      ||
                    attrs[XFRMA_ALG_COMP]       ||
                    attrs[XFRMA_TFCPAD])
                        goto out;
                break;

        case IPPROTO_ESP:
                if (attrs[XFRMA_ALG_COMP])
                        goto out;
                if (!attrs[XFRMA_ALG_AUTH] &&
                    !attrs[XFRMA_ALG_AUTH_TRUNC] &&
                    !attrs[XFRMA_ALG_CRYPT] &&
                    !attrs[XFRMA_ALG_AEAD])
                        goto out;
                if ((attrs[XFRMA_ALG_AUTH] ||
                     attrs[XFRMA_ALG_AUTH_TRUNC] ||
                     attrs[XFRMA_ALG_CRYPT]) &&
                    attrs[XFRMA_ALG_AEAD])
                        goto out;
                if (attrs[XFRMA_TFCPAD] &&
                    p->mode != XFRM_MODE_TUNNEL)
                        goto out;
                break;

        case IPPROTO_COMP:
                if (!attrs[XFRMA_ALG_COMP]      ||
                    attrs[XFRMA_ALG_AEAD]       ||
                    attrs[XFRMA_ALG_AUTH]       ||
                    attrs[XFRMA_ALG_AUTH_TRUNC] ||
                    attrs[XFRMA_ALG_CRYPT]      ||
                    attrs[XFRMA_TFCPAD]         ||
                    (ntohl(p->id.spi) >= 0x10000))
                        goto out;
                break;

#if IS_ENABLED(CONFIG_IPV6)
        case IPPROTO_DSTOPTS:
        case IPPROTO_ROUTING:
                if (attrs[XFRMA_ALG_COMP]       ||
                    attrs[XFRMA_ALG_AUTH]       ||
                    attrs[XFRMA_ALG_AUTH_TRUNC] ||
                    attrs[XFRMA_ALG_AEAD]       ||
                    attrs[XFRMA_ALG_CRYPT]      ||
                    attrs[XFRMA_ENCAP]          ||
                    attrs[XFRMA_SEC_CTX]        ||
                    attrs[XFRMA_TFCPAD]         ||
                    !attrs[XFRMA_COADDR])
                        goto out;
                break;
#endif

        default:
                goto out;
        }

        if ((err = verify_aead(attrs)))
                goto out;
        if ((err = verify_auth_trunc(attrs)))
                goto out;
        if ((err = verify_one_alg(attrs, XFRMA_ALG_AUTH)))
                goto out;
        if ((err = verify_one_alg(attrs, XFRMA_ALG_CRYPT)))
                goto out;
        if ((err = verify_one_alg(attrs, XFRMA_ALG_COMP)))
                goto out;
        if ((err = verify_sec_ctx_len(attrs)))
                goto out;
        if ((err = verify_replay(p, attrs)))
                goto out;

        err = -EINVAL;
        switch (p->mode) {
        case XFRM_MODE_TRANSPORT:
        case XFRM_MODE_TUNNEL:
        case XFRM_MODE_ROUTEOPTIMIZATION:
        case XFRM_MODE_BEET:
                break;

        default:
                goto out;
        }

        err = 0;

out:
        return err;
}

static int attach_one_algo(struct xfrm_algo **algpp, u8 *props,
                           struct xfrm_algo_desc *(*get_byname)(const char *, int),
                           struct nlattr *rta)
{
        struct xfrm_algo *p, *ualg;
        struct xfrm_algo_desc *algo;

        if (!rta)
                return 0;

        ualg = nla_data(rta);

        algo = get_byname(ualg->alg_name, 1);
        if (!algo)
                return -ENOSYS;
        *props = algo->desc.sadb_alg_id;

        p = kmemdup(ualg, xfrm_alg_len(ualg), GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        strcpy(p->alg_name, algo->name);
        *algpp = p;
        return 0;
}

static int attach_crypt(struct xfrm_state *x, struct nlattr *rta)
{
        struct xfrm_algo *p, *ualg;
        struct xfrm_algo_desc *algo;

        if (!rta)
                return 0;

        ualg = nla_data(rta);

        algo = xfrm_ealg_get_byname(ualg->alg_name, 1);
        if (!algo)
                return -ENOSYS;
        x->props.ealgo = algo->desc.sadb_alg_id;

        p = kmemdup(ualg, xfrm_alg_len(ualg), GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        strcpy(p->alg_name, algo->name);
        x->ealg = p;
        x->geniv = algo->uinfo.encr.geniv;
        return 0;
}

static int attach_auth(struct xfrm_algo_auth **algpp, u8 *props,
                       struct nlattr *rta)
{
        struct xfrm_algo *ualg;
        struct xfrm_algo_auth *p;
        struct xfrm_algo_desc *algo;

        if (!rta)
                return 0;

        ualg = nla_data(rta);

        algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
        if (!algo)
                return -ENOSYS;
        *props = algo->desc.sadb_alg_id;

        p = kmalloc(sizeof(*p) + (ualg->alg_key_len + 7) / 8, GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        strcpy(p->alg_name, algo->name);
        p->alg_key_len = ualg->alg_key_len;
        p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;
        memcpy(p->alg_key, ualg->alg_key, (ualg->alg_key_len + 7) / 8);

        *algpp = p;
        return 0;
}

static int attach_auth_trunc(struct xfrm_algo_auth **algpp, u8 *props,
                             struct nlattr *rta)
{
        struct xfrm_algo_auth *p, *ualg;
        struct xfrm_algo_desc *algo;

        if (!rta)
                return 0;

        ualg = nla_data(rta);

        algo = xfrm_aalg_get_byname(ualg->alg_name, 1);
        if (!algo)
                return -ENOSYS;
        if (ualg->alg_trunc_len > algo->uinfo.auth.icv_fullbits)
                return -EINVAL;
        *props = algo->desc.sadb_alg_id;

        p = kmemdup(ualg, xfrm_alg_auth_len(ualg), GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        strcpy(p->alg_name, algo->name);
        if (!p->alg_trunc_len)
                p->alg_trunc_len = algo->uinfo.auth.icv_truncbits;

        *algpp = p;
        return 0;
}

static int attach_aead(struct xfrm_state *x, struct nlattr *rta)
{
        struct xfrm_algo_aead *p, *ualg;
        struct xfrm_algo_desc *algo;

        if (!rta)
                return 0;

        ualg = nla_data(rta);

        algo = xfrm_aead_get_byname(ualg->alg_name, ualg->alg_icv_len, 1);
        if (!algo)
                return -ENOSYS;
        x->props.ealgo = algo->desc.sadb_alg_id;

        p = kmemdup(ualg, aead_len(ualg), GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        strcpy(p->alg_name, algo->name);
        x->aead = p;
        x->geniv = algo->uinfo.aead.geniv;
        return 0;
}

static inline int xfrm_replay_verify_len(struct xfrm_replay_state_esn *replay_esn,
                                         struct nlattr *rp)
{
        struct xfrm_replay_state_esn *up;
        unsigned int ulen;

        if (!replay_esn || !rp)
                return 0;

        up = nla_data(rp);
        ulen = xfrm_replay_state_esn_len(up);

        /* Check the overall length and the internal bitmap length to avoid
         * potential overflow. */
        if (nla_len(rp) < (int)ulen ||
            xfrm_replay_state_esn_len(replay_esn) != ulen ||
            replay_esn->bmp_len != up->bmp_len)
                return -EINVAL;

        if (up->replay_window > up->bmp_len * sizeof(__u32) * 8)
                return -EINVAL;

        return 0;
}

static int xfrm_alloc_replay_state_esn(struct xfrm_replay_state_esn **replay_esn,
                                       struct xfrm_replay_state_esn **preplay_esn,
                                       struct nlattr *rta)
{
        struct xfrm_replay_state_esn *p, *pp, *up;
        unsigned int klen, ulen;

        if (!rta)
                return 0;

        up = nla_data(rta);
        klen = xfrm_replay_state_esn_len(up);
        ulen = nla_len(rta) >= (int)klen ? klen : sizeof(*up);

        p = kzalloc(klen, GFP_KERNEL);
        if (!p)
                return -ENOMEM;

        pp = kzalloc(klen, GFP_KERNEL);
        if (!pp) {
                kfree(p);
                return -ENOMEM;
        }

        memcpy(p, up, ulen);
        memcpy(pp, up, ulen);

        *replay_esn = p;
        *preplay_esn = pp;

        return 0;
}

static inline unsigned int xfrm_user_sec_ctx_size(struct xfrm_sec_ctx *xfrm_ctx)
{
        unsigned int len = 0;

        if (xfrm_ctx) {
                len += sizeof(struct xfrm_user_sec_ctx);
                len += xfrm_ctx->ctx_len;
        }
        return len;
}

static void copy_from_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
{
        memcpy(&x->id, &p->id, sizeof(x->id));
        memcpy(&x->sel, &p->sel, sizeof(x->sel));
        memcpy(&x->lft, &p->lft, sizeof(x->lft));
        x->props.mode = p->mode;
        x->props.replay_window = min_t(unsigned int, p->replay_window,
                                        sizeof(x->replay.bitmap) * 8);
        x->props.reqid = p->reqid;
        x->props.family = p->family;
        memcpy(&x->props.saddr, &p->saddr, sizeof(x->props.saddr));
        x->props.flags = p->flags;

        if (!x->sel.family && !(p->flags & XFRM_STATE_AF_UNSPEC))
                x->sel.family = p->family;
}

/*
 * someday when pfkey also has support, we could have the code
 * somehow made shareable and move it to xfrm_state.c - JHS
 *
*/
static void xfrm_update_ae_params(struct xfrm_state *x, struct nlattr **attrs,
                                  int update_esn)
{
        struct nlattr *rp = attrs[XFRMA_REPLAY_VAL];
        struct nlattr *re = update_esn ? attrs[XFRMA_REPLAY_ESN_VAL] : NULL;
        struct nlattr *lt = attrs[XFRMA_LTIME_VAL];
        struct nlattr *et = attrs[XFRMA_ETIMER_THRESH];
        struct nlattr *rt = attrs[XFRMA_REPLAY_THRESH];

        if (re) {
                struct xfrm_replay_state_esn *replay_esn;
                replay_esn = nla_data(re);
                memcpy(x->replay_esn, replay_esn,
                       xfrm_replay_state_esn_len(replay_esn));
                memcpy(x->preplay_esn, replay_esn,
                       xfrm_replay_state_esn_len(replay_esn));
        }

        if (rp) {
                struct xfrm_replay_state *replay;
                replay = nla_data(rp);
                memcpy(&x->replay, replay, sizeof(*replay));
                memcpy(&x->preplay, replay, sizeof(*replay));
        }

        if (lt) {
                struct xfrm_lifetime_cur *ltime;
                ltime = nla_data(lt);
                x->curlft.bytes = ltime->bytes;
                x->curlft.packets = ltime->packets;
                x->curlft.add_time = ltime->add_time;
                x->curlft.use_time = ltime->use_time;
        }

        if (et)
                x->replay_maxage = nla_get_u32(et);

        if (rt)
                x->replay_maxdiff = nla_get_u32(rt);
}

static void xfrm_smark_init(struct nlattr **attrs, struct xfrm_mark *m)
{
        if (attrs[XFRMA_SET_MARK]) {
                m->v = nla_get_u32(attrs[XFRMA_SET_MARK]);
                if (attrs[XFRMA_SET_MARK_MASK])
                        m->m = nla_get_u32(attrs[XFRMA_SET_MARK_MASK]);
                else
                        m->m = 0xffffffff;
        } else {
                m->v = m->m = 0;
        }
}

static struct xfrm_state *xfrm_state_construct(struct net *net,
                                               struct xfrm_usersa_info *p,
                                               struct nlattr **attrs,
                                               int *errp)
{
        struct xfrm_state *x = xfrm_state_alloc(net);
        struct xfrm_mark smark;
        int err = -ENOMEM;

        if (!x)
                goto error_no_put;

        copy_from_user_state(x, p);

        if (attrs[XFRMA_SA_EXTRA_FLAGS])
                x->props.extra_flags = nla_get_u32(attrs[XFRMA_SA_EXTRA_FLAGS]);

        if ((err = attach_aead(x, attrs[XFRMA_ALG_AEAD])))
                goto error;
        if ((err = attach_auth_trunc(&x->aalg, &x->props.aalgo,
                                     attrs[XFRMA_ALG_AUTH_TRUNC])))
                goto error;
        if (!x->props.aalgo) {
                if ((err = attach_auth(&x->aalg, &x->props.aalgo,
                                       attrs[XFRMA_ALG_AUTH])))
                        goto error;
        }
        if ((err = attach_crypt(x, attrs[XFRMA_ALG_CRYPT])))
                goto error;
        if ((err = attach_one_algo(&x->calg, &x->props.calgo,
                                   xfrm_calg_get_byname,
                                   attrs[XFRMA_ALG_COMP])))
                goto error;

        if (attrs[XFRMA_ENCAP]) {
                x->encap = kmemdup(nla_data(attrs[XFRMA_ENCAP]),
                                   sizeof(*x->encap), GFP_KERNEL);
                if (x->encap == NULL)
                        goto error;
        }

        if (attrs[XFRMA_TFCPAD])
                x->tfcpad = nla_get_u32(attrs[XFRMA_TFCPAD]);

        if (attrs[XFRMA_COADDR]) {
                x->coaddr = kmemdup(nla_data(attrs[XFRMA_COADDR]),
                                    sizeof(*x->coaddr), GFP_KERNEL);
                if (x->coaddr == NULL)
                        goto error;
        }

        xfrm_mark_get(attrs, &x->mark);

        xfrm_smark_init(attrs, &smark);
        x->props.output_mark = smark.v;
        x->output_mark_mask = smark.m;

        if (attrs[XFRMA_IF_ID])
                x->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);

        err = __xfrm_init_state(x, false, attrs[XFRMA_OFFLOAD_DEV]);
        if (err)
                goto error;

        if (attrs[XFRMA_SEC_CTX]) {
                err = security_xfrm_state_alloc(x,
                                                nla_data(attrs[XFRMA_SEC_CTX]));
                if (err)
                        goto error;
        }

        if ((err = xfrm_alloc_replay_state_esn(&x->replay_esn, &x->preplay_esn,
                                               attrs[XFRMA_REPLAY_ESN_VAL])))
                goto error;

        x->km.seq = p->seq;
        x->replay_maxdiff = net->xfrm.sysctl_aevent_rseqth;
        /* sysctl_xfrm_aevent_etime is in 100ms units */
        x->replay_maxage = (net->xfrm.sysctl_aevent_etime*HZ)/XFRM_AE_ETH_M;

        if ((err = xfrm_init_replay(x)))
                goto error;

        /* override default values from above */
        xfrm_update_ae_params(x, attrs, 0);

        /* configure the hardware if offload is requested */
        if (attrs[XFRMA_OFFLOAD_DEV]) {
                err = xfrm_dev_state_add(net, x,
                                         nla_data(attrs[XFRMA_OFFLOAD_DEV]));
                if (err)
                        goto error;
        }

        return x;

error:
        x->km.state = XFRM_STATE_DEAD;
        xfrm_state_put(x);
error_no_put:
        *errp = err;
        return NULL;
}

static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_usersa_info *p = nlmsg_data(nlh);
        struct xfrm_state *x;
        int err;
        struct km_event c;

        err = verify_newsa_info(p, attrs);
        if (err)
                return err;

        x = xfrm_state_construct(net, p, attrs, &err);
        if (!x)
                return err;

        xfrm_state_hold(x);
        if (nlh->nlmsg_type == XFRM_MSG_NEWSA)
                err = xfrm_state_add(x);
        else
                err = xfrm_state_update(x);

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

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

        if (x->km.state == XFRM_STATE_VOID)
                x->km.state = XFRM_STATE_VALID;

        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        c.event = nlh->nlmsg_type;

        km_state_notify(x, &c);
out:
        xfrm_state_put(x);
        return err;
}

static struct xfrm_state *xfrm_user_state_lookup(struct net *net,
                                                 struct xfrm_usersa_id *p,
                                                 struct nlattr **attrs,
                                                 int *errp)
{
        struct xfrm_state *x = NULL;
        struct xfrm_mark m;
        int err;
        u32 mark = xfrm_mark_get(attrs, &m);

        if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY)) {
                err = -ESRCH;
                x = xfrm_state_lookup(net, mark, &p->daddr, p->spi, p->proto, p->family);
        } else {
                xfrm_address_t *saddr = NULL;

                verify_one_addr(attrs, XFRMA_SRCADDR, &saddr);
                if (!saddr) {
                        err = -EINVAL;
                        goto out;
                }

                err = -ESRCH;
                x = xfrm_state_lookup_byaddr(net, mark,
                                             &p->daddr, saddr,
                                             p->proto, p->family);
        }

 out:
        if (!x && errp)
                *errp = err;
        return x;
}

static int xfrm_del_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state *x;
        int err = -ESRCH;
        struct km_event c;
        struct xfrm_usersa_id *p = nlmsg_data(nlh);

        x = xfrm_user_state_lookup(net, p, attrs, &err);
        if (x == NULL)
                return err;

        if ((err = security_xfrm_state_delete(x)) != 0)
                goto out;

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

        err = xfrm_state_delete(x);

        if (err < 0)
                goto out;

        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        c.event = nlh->nlmsg_type;
        km_state_notify(x, &c);

out:
        xfrm_audit_state_delete(x, err ? 0 : 1, true);
        xfrm_state_put(x);
        return err;
}

static void copy_to_user_state(struct xfrm_state *x, struct xfrm_usersa_info *p)
{
        memset(p, 0, sizeof(*p));
        memcpy(&p->id, &x->id, sizeof(p->id));
        memcpy(&p->sel, &x->sel, sizeof(p->sel));
        memcpy(&p->lft, &x->lft, sizeof(p->lft));
        memcpy(&p->curlft, &x->curlft, sizeof(p->curlft));
        put_unaligned(x->stats.replay_window, &p->stats.replay_window);
        put_unaligned(x->stats.replay, &p->stats.replay);
        put_unaligned(x->stats.integrity_failed, &p->stats.integrity_failed);
        memcpy(&p->saddr, &x->props.saddr, sizeof(p->saddr));
        p->mode = x->props.mode;
        p->replay_window = x->props.replay_window;
        p->reqid = x->props.reqid;
        p->family = x->props.family;
        p->flags = x->props.flags;
        p->seq = x->km.seq;
}

struct xfrm_dump_info {
        struct sk_buff *in_skb;
        struct sk_buff *out_skb;
        u32 nlmsg_seq;
        u16 nlmsg_flags;
};

static int copy_sec_ctx(struct xfrm_sec_ctx *s, struct sk_buff *skb)
{
        struct xfrm_user_sec_ctx *uctx;
        struct nlattr *attr;
        int ctx_size = sizeof(*uctx) + s->ctx_len;

        attr = nla_reserve(skb, XFRMA_SEC_CTX, ctx_size);
        if (attr == NULL)
                return -EMSGSIZE;

        uctx = nla_data(attr);
        uctx->exttype = XFRMA_SEC_CTX;
        uctx->len = ctx_size;
        uctx->ctx_doi = s->ctx_doi;
        uctx->ctx_alg = s->ctx_alg;
        uctx->ctx_len = s->ctx_len;
        memcpy(uctx + 1, s->ctx_str, s->ctx_len);

        return 0;
}

static int copy_user_offload(struct xfrm_state_offload *xso, struct sk_buff *skb)
{
        struct xfrm_user_offload *xuo;
        struct nlattr *attr;

        attr = nla_reserve(skb, XFRMA_OFFLOAD_DEV, sizeof(*xuo));
        if (attr == NULL)
                return -EMSGSIZE;

        xuo = nla_data(attr);
        memset(xuo, 0, sizeof(*xuo));
        xuo->ifindex = xso->dev->ifindex;
        xuo->flags = xso->flags;

        return 0;
}

static int copy_to_user_auth(struct xfrm_algo_auth *auth, struct sk_buff *skb)
{
        struct xfrm_algo *algo;
        struct nlattr *nla;

        nla = nla_reserve(skb, XFRMA_ALG_AUTH,
                          sizeof(*algo) + (auth->alg_key_len + 7) / 8);
        if (!nla)
                return -EMSGSIZE;

        algo = nla_data(nla);
        strncpy(algo->alg_name, auth->alg_name, sizeof(algo->alg_name));
        memcpy(algo->alg_key, auth->alg_key, (auth->alg_key_len + 7) / 8);
        algo->alg_key_len = auth->alg_key_len;

        return 0;
}

static int xfrm_smark_put(struct sk_buff *skb, struct xfrm_mark *m)
{
        int ret = 0;

        if (m->v | m->m) {
                ret = nla_put_u32(skb, XFRMA_SET_MARK, m->v);
                if (!ret)
                        ret = nla_put_u32(skb, XFRMA_SET_MARK_MASK, m->m);
        }
        return ret;
}

/* Don't change this without updating xfrm_sa_len! */
static int copy_to_user_state_extra(struct xfrm_state *x,
                                    struct xfrm_usersa_info *p,
                                    struct sk_buff *skb)
{
        struct xfrm_mark smark;
        int ret = 0;

        copy_to_user_state(x, p);

        if (x->props.extra_flags) {
                ret = nla_put_u32(skb, XFRMA_SA_EXTRA_FLAGS,
                                  x->props.extra_flags);
                if (ret)
                        goto out;
        }

        if (x->coaddr) {
                ret = nla_put(skb, XFRMA_COADDR, sizeof(*x->coaddr), x->coaddr);
                if (ret)
                        goto out;
        }
        if (x->lastused) {
                ret = nla_put_u64_64bit(skb, XFRMA_LASTUSED, x->lastused,
                                        XFRMA_PAD);
                if (ret)
                        goto out;
        }
        if (x->aead) {
                ret = nla_put(skb, XFRMA_ALG_AEAD, aead_len(x->aead), x->aead);
                if (ret)
                        goto out;
        }
        if (x->aalg) {
                ret = copy_to_user_auth(x->aalg, skb);
                if (!ret)
                        ret = nla_put(skb, XFRMA_ALG_AUTH_TRUNC,
                                      xfrm_alg_auth_len(x->aalg), x->aalg);
                if (ret)
                        goto out;
        }
        if (x->ealg) {
                ret = nla_put(skb, XFRMA_ALG_CRYPT, xfrm_alg_len(x->ealg), x->ealg);
                if (ret)
                        goto out;
        }
        if (x->calg) {
                ret = nla_put(skb, XFRMA_ALG_COMP, sizeof(*(x->calg)), x->calg);
                if (ret)
                        goto out;
        }
        if (x->encap) {
                ret = nla_put(skb, XFRMA_ENCAP, sizeof(*x->encap), x->encap);
                if (ret)
                        goto out;
        }
        if (x->tfcpad) {
                ret = nla_put_u32(skb, XFRMA_TFCPAD, x->tfcpad);
                if (ret)
                        goto out;
        }
        ret = xfrm_mark_put(skb, &x->mark);
        if (ret)
                goto out;

        smark.v = x->props.output_mark;
        smark.m = x->output_mark_mask;
        ret = xfrm_smark_put(skb, &smark);
        if (ret)
                goto out;

        if (x->replay_esn)
                ret = nla_put(skb, XFRMA_REPLAY_ESN_VAL,
                              xfrm_replay_state_esn_len(x->replay_esn),
                              x->replay_esn);
        else
                ret = nla_put(skb, XFRMA_REPLAY_VAL, sizeof(x->replay),
                              &x->replay);
        if (ret)
                goto out;
        if(x->xso.dev)
                ret = copy_user_offload(&x->xso, skb);
        if (ret)
                goto out;
        if (x->if_id) {
                ret = nla_put_u32(skb, XFRMA_IF_ID, x->if_id);
                if (ret)
                        goto out;
        }
        if (x->security)
                ret = copy_sec_ctx(x->security, skb);
out:
        return ret;
}

static int dump_one_state(struct xfrm_state *x, int count, void *ptr)
{
        struct xfrm_dump_info *sp = ptr;
        struct sk_buff *in_skb = sp->in_skb;
        struct sk_buff *skb = sp->out_skb;
        struct xfrm_usersa_info *p;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, sp->nlmsg_seq,
                        XFRM_MSG_NEWSA, sizeof(*p), sp->nlmsg_flags);
        if (nlh == NULL)
                return -EMSGSIZE;

        p = nlmsg_data(nlh);

        err = copy_to_user_state_extra(x, p, skb);
        if (err) {
                nlmsg_cancel(skb, nlh);
                return err;
        }
        nlmsg_end(skb, nlh);
        return 0;

}

static int xfrm_dump_sa_done(struct netlink_callback *cb)
{
        struct xfrm_state_walk *walk = (struct xfrm_state_walk *) &cb->args[1];
        struct sock *sk = cb->skb->sk;
        struct net *net = sock_net(sk);

        if (cb->args[0])
                xfrm_state_walk_done(walk, net);
        return 0;
}

static const struct nla_policy xfrma_policy[XFRMA_MAX+1];
static int xfrm_dump_sa(struct sk_buff *skb, struct netlink_callback *cb)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state_walk *walk = (struct xfrm_state_walk *) &cb->args[1];
        struct xfrm_dump_info info;

        BUILD_BUG_ON(sizeof(struct xfrm_state_walk) >
                     sizeof(cb->args) - sizeof(cb->args[0]));

        info.in_skb = cb->skb;
        info.out_skb = skb;
        info.nlmsg_seq = cb->nlh->nlmsg_seq;
        info.nlmsg_flags = NLM_F_MULTI;

        if (!cb->args[0]) {
                struct nlattr *attrs[XFRMA_MAX+1];
                struct xfrm_address_filter *filter = NULL;
                u8 proto = 0;
                int err;

                err = nlmsg_parse_deprecated(cb->nlh, 0, attrs, XFRMA_MAX,
                                             xfrma_policy, cb->extack);
                if (err < 0)
                        return err;

                if (attrs[XFRMA_ADDRESS_FILTER]) {
                        filter = kmemdup(nla_data(attrs[XFRMA_ADDRESS_FILTER]),
                                         sizeof(*filter), GFP_KERNEL);
                        if (filter == NULL)
                                return -ENOMEM;
                }

                if (attrs[XFRMA_PROTO])
                        proto = nla_get_u8(attrs[XFRMA_PROTO]);

                xfrm_state_walk_init(walk, proto, filter);
                cb->args[0] = 1;
        }

        (void) xfrm_state_walk(net, walk, dump_one_state, &info);

        return skb->len;
}

static struct sk_buff *xfrm_state_netlink(struct sk_buff *in_skb,
                                          struct xfrm_state *x, u32 seq)
{
        struct xfrm_dump_info info;
        struct sk_buff *skb;
        int err;

        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
        if (!skb)
                return ERR_PTR(-ENOMEM);

        info.in_skb = in_skb;
        info.out_skb = skb;
        info.nlmsg_seq = seq;
        info.nlmsg_flags = 0;

        err = dump_one_state(x, 0, &info);
        if (err) {
                kfree_skb(skb);
                return ERR_PTR(err);
        }

        return skb;
}

/* A wrapper for nlmsg_multicast() checking that nlsk is still available.
 * Must be called with RCU read lock.
 */
static inline int xfrm_nlmsg_multicast(struct net *net, struct sk_buff *skb,
                                       u32 pid, unsigned int group)
{
        struct sock *nlsk = rcu_dereference(net->xfrm.nlsk);

        if (!nlsk) {
                kfree_skb(skb);
                return -EPIPE;
        }

        return nlmsg_multicast(nlsk, skb, pid, group, GFP_ATOMIC);
}

static inline unsigned int xfrm_spdinfo_msgsize(void)
{
        return NLMSG_ALIGN(4)
               + nla_total_size(sizeof(struct xfrmu_spdinfo))
               + nla_total_size(sizeof(struct xfrmu_spdhinfo))
               + nla_total_size(sizeof(struct xfrmu_spdhthresh))
               + nla_total_size(sizeof(struct xfrmu_spdhthresh));
}

static int build_spdinfo(struct sk_buff *skb, struct net *net,
                         u32 portid, u32 seq, u32 flags)
{
        struct xfrmk_spdinfo si;
        struct xfrmu_spdinfo spc;
        struct xfrmu_spdhinfo sph;
        struct xfrmu_spdhthresh spt4, spt6;
        struct nlmsghdr *nlh;
        int err;
        u32 *f;
        unsigned lseq;

        nlh = nlmsg_put(skb, portid, seq, XFRM_MSG_NEWSPDINFO, sizeof(u32), 0);
        if (nlh == NULL) /* shouldn't really happen ... */
                return -EMSGSIZE;

        f = nlmsg_data(nlh);
        *f = flags;
        xfrm_spd_getinfo(net, &si);
        spc.incnt = si.incnt;
        spc.outcnt = si.outcnt;
        spc.fwdcnt = si.fwdcnt;
        spc.inscnt = si.inscnt;
        spc.outscnt = si.outscnt;
        spc.fwdscnt = si.fwdscnt;
        sph.spdhcnt = si.spdhcnt;
        sph.spdhmcnt = si.spdhmcnt;

        do {
                lseq = read_seqbegin(&net->xfrm.policy_hthresh.lock);

                spt4.lbits = net->xfrm.policy_hthresh.lbits4;
                spt4.rbits = net->xfrm.policy_hthresh.rbits4;
                spt6.lbits = net->xfrm.policy_hthresh.lbits6;
                spt6.rbits = net->xfrm.policy_hthresh.rbits6;
        } while (read_seqretry(&net->xfrm.policy_hthresh.lock, lseq));

        err = nla_put(skb, XFRMA_SPD_INFO, sizeof(spc), &spc);
        if (!err)
                err = nla_put(skb, XFRMA_SPD_HINFO, sizeof(sph), &sph);
        if (!err)
                err = nla_put(skb, XFRMA_SPD_IPV4_HTHRESH, sizeof(spt4), &spt4);
        if (!err)
                err = nla_put(skb, XFRMA_SPD_IPV6_HTHRESH, sizeof(spt6), &spt6);
        if (err) {
                nlmsg_cancel(skb, nlh);
                return err;
        }

        nlmsg_end(skb, nlh);
        return 0;
}

static int xfrm_set_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
                            struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrmu_spdhthresh *thresh4 = NULL;
        struct xfrmu_spdhthresh *thresh6 = NULL;

        /* selector prefixlen thresholds to hash policies */
        if (attrs[XFRMA_SPD_IPV4_HTHRESH]) {
                struct nlattr *rta = attrs[XFRMA_SPD_IPV4_HTHRESH];

                if (nla_len(rta) < sizeof(*thresh4))
                        return -EINVAL;
                thresh4 = nla_data(rta);
                if (thresh4->lbits > 32 || thresh4->rbits > 32)
                        return -EINVAL;
        }
        if (attrs[XFRMA_SPD_IPV6_HTHRESH]) {
                struct nlattr *rta = attrs[XFRMA_SPD_IPV6_HTHRESH];

                if (nla_len(rta) < sizeof(*thresh6))
                        return -EINVAL;
                thresh6 = nla_data(rta);
                if (thresh6->lbits > 128 || thresh6->rbits > 128)
                        return -EINVAL;
        }

        if (thresh4 || thresh6) {
                write_seqlock(&net->xfrm.policy_hthresh.lock);
                if (thresh4) {
                        net->xfrm.policy_hthresh.lbits4 = thresh4->lbits;
                        net->xfrm.policy_hthresh.rbits4 = thresh4->rbits;
                }
                if (thresh6) {
                        net->xfrm.policy_hthresh.lbits6 = thresh6->lbits;
                        net->xfrm.policy_hthresh.rbits6 = thresh6->rbits;
                }
                write_sequnlock(&net->xfrm.policy_hthresh.lock);

                xfrm_policy_hash_rebuild(net);
        }

        return 0;
}

static int xfrm_get_spdinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct sk_buff *r_skb;
        u32 *flags = nlmsg_data(nlh);
        u32 sportid = NETLINK_CB(skb).portid;
        u32 seq = nlh->nlmsg_seq;
        int err;

        r_skb = nlmsg_new(xfrm_spdinfo_msgsize(), GFP_ATOMIC);
        if (r_skb == NULL)
                return -ENOMEM;

        err = build_spdinfo(r_skb, net, sportid, seq, *flags);
        BUG_ON(err < 0);

        return nlmsg_unicast(net->xfrm.nlsk, r_skb, sportid);
}

static inline unsigned int xfrm_sadinfo_msgsize(void)
{
        return NLMSG_ALIGN(4)
               + nla_total_size(sizeof(struct xfrmu_sadhinfo))
               + nla_total_size(4); /* XFRMA_SAD_CNT */
}

static int build_sadinfo(struct sk_buff *skb, struct net *net,
                         u32 portid, u32 seq, u32 flags)
{
        struct xfrmk_sadinfo si;
        struct xfrmu_sadhinfo sh;
        struct nlmsghdr *nlh;
        int err;
        u32 *f;

        nlh = nlmsg_put(skb, portid, seq, XFRM_MSG_NEWSADINFO, sizeof(u32), 0);
        if (nlh == NULL) /* shouldn't really happen ... */
                return -EMSGSIZE;

        f = nlmsg_data(nlh);
        *f = flags;
        xfrm_sad_getinfo(net, &si);

        sh.sadhmcnt = si.sadhmcnt;
        sh.sadhcnt = si.sadhcnt;

        err = nla_put_u32(skb, XFRMA_SAD_CNT, si.sadcnt);
        if (!err)
                err = nla_put(skb, XFRMA_SAD_HINFO, sizeof(sh), &sh);
        if (err) {
                nlmsg_cancel(skb, nlh);
                return err;
        }

        nlmsg_end(skb, nlh);
        return 0;
}

static int xfrm_get_sadinfo(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct sk_buff *r_skb;
        u32 *flags = nlmsg_data(nlh);
        u32 sportid = NETLINK_CB(skb).portid;
        u32 seq = nlh->nlmsg_seq;
        int err;

        r_skb = nlmsg_new(xfrm_sadinfo_msgsize(), GFP_ATOMIC);
        if (r_skb == NULL)
                return -ENOMEM;

        err = build_sadinfo(r_skb, net, sportid, seq, *flags);
        BUG_ON(err < 0);

        return nlmsg_unicast(net->xfrm.nlsk, r_skb, sportid);
}

static int xfrm_get_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_usersa_id *p = nlmsg_data(nlh);
        struct xfrm_state *x;
        struct sk_buff *resp_skb;
        int err = -ESRCH;

        x = xfrm_user_state_lookup(net, p, attrs, &err);
        if (x == NULL)
                goto out_noput;

        resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
        if (IS_ERR(resp_skb)) {
                err = PTR_ERR(resp_skb);
        } else {
                err = nlmsg_unicast(net->xfrm.nlsk, resp_skb, NETLINK_CB(skb).portid);
        }
        xfrm_state_put(x);
out_noput:
        return err;
}

static int xfrm_alloc_userspi(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state *x;
        struct xfrm_userspi_info *p;
        struct sk_buff *resp_skb;
        xfrm_address_t *daddr;
        int family;
        int err;
        u32 mark;
        struct xfrm_mark m;
        u32 if_id = 0;

        p = nlmsg_data(nlh);
        err = verify_spi_info(p->info.id.proto, p->min, p->max);
        if (err)
                goto out_noput;

        family = p->info.family;
        daddr = &p->info.id.daddr;

        x = NULL;

        mark = xfrm_mark_get(attrs, &m);

        if (attrs[XFRMA_IF_ID])
                if_id = nla_get_u32(attrs[XFRMA_IF_ID]);

        if (p->info.seq) {
                x = xfrm_find_acq_byseq(net, mark, p->info.seq);
                if (x && !xfrm_addr_equal(&x->id.daddr, daddr, family)) {
                        xfrm_state_put(x);
                        x = NULL;
                }
        }

        if (!x)
                x = xfrm_find_acq(net, &m, p->info.mode, p->info.reqid,
                                  if_id, p->info.id.proto, daddr,
                                  &p->info.saddr, 1,
                                  family);
        err = -ENOENT;
        if (x == NULL)
                goto out_noput;

        err = xfrm_alloc_spi(x, p->min, p->max);
        if (err)
                goto out;

        resp_skb = xfrm_state_netlink(skb, x, nlh->nlmsg_seq);
        if (IS_ERR(resp_skb)) {
                err = PTR_ERR(resp_skb);
                goto out;
        }

        err = nlmsg_unicast(net->xfrm.nlsk, resp_skb, NETLINK_CB(skb).portid);

out:
        xfrm_state_put(x);
out_noput:
        return err;
}

static int verify_policy_dir(u8 dir)
{
        switch (dir) {
        case XFRM_POLICY_IN:
        case XFRM_POLICY_OUT:
        case XFRM_POLICY_FWD:
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

static int verify_policy_type(u8 type)
{
        switch (type) {
        case XFRM_POLICY_TYPE_MAIN:
#ifdef CONFIG_XFRM_SUB_POLICY
        case XFRM_POLICY_TYPE_SUB:
#endif
                break;

        default:
                return -EINVAL;
        }

        return 0;
}

static int verify_newpolicy_info(struct xfrm_userpolicy_info *p)
{
        int ret;

        switch (p->share) {
        case XFRM_SHARE_ANY:
        case XFRM_SHARE_SESSION:
        case XFRM_SHARE_USER:
        case XFRM_SHARE_UNIQUE:
                break;

        default:
                return -EINVAL;
        }

        switch (p->action) {
        case XFRM_POLICY_ALLOW:
        case XFRM_POLICY_BLOCK:
                break;

        default:
                return -EINVAL;
        }

        switch (p->sel.family) {
        case AF_INET:
                if (p->sel.prefixlen_d > 32 || p->sel.prefixlen_s > 32)
                        return -EINVAL;

                break;

        case AF_INET6:
#if IS_ENABLED(CONFIG_IPV6)
                if (p->sel.prefixlen_d > 128 || p->sel.prefixlen_s > 128)
                        return -EINVAL;

                break;
#else
                return  -EAFNOSUPPORT;
#endif

        default:
                return -EINVAL;
        }

        ret = verify_policy_dir(p->dir);
        if (ret)
                return ret;
        if (p->index && (xfrm_policy_id2dir(p->index) != p->dir))
                return -EINVAL;

        return 0;
}

static int copy_from_user_sec_ctx(struct xfrm_policy *pol, struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_SEC_CTX];
        struct xfrm_user_sec_ctx *uctx;

        if (!rt)
                return 0;

        uctx = nla_data(rt);
        return security_xfrm_policy_alloc(&pol->security, uctx, GFP_KERNEL);
}

static void copy_templates(struct xfrm_policy *xp, struct xfrm_user_tmpl *ut,
                           int nr)
{
        int i;

        xp->xfrm_nr = nr;
        for (i = 0; i < nr; i++, ut++) {
                struct xfrm_tmpl *t = &xp->xfrm_vec[i];

                memcpy(&t->id, &ut->id, sizeof(struct xfrm_id));
                memcpy(&t->saddr, &ut->saddr,
                       sizeof(xfrm_address_t));
                t->reqid = ut->reqid;
                t->mode = ut->mode;
                t->share = ut->share;
                t->optional = ut->optional;
                t->aalgos = ut->aalgos;
                t->ealgos = ut->ealgos;
                t->calgos = ut->calgos;
                /* If all masks are ~0, then we allow all algorithms. */
                t->allalgs = !~(t->aalgos & t->ealgos & t->calgos);
                t->encap_family = ut->family;
        }
}

static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family)
{
        u16 prev_family;
        int i;

        if (nr > XFRM_MAX_DEPTH)
                return -EINVAL;

        prev_family = family;

        for (i = 0; i < nr; i++) {
                /* We never validated the ut->family value, so many
                 * applications simply leave it at zero.  The check was
                 * never made and ut->family was ignored because all
                 * templates could be assumed to have the same family as
                 * the policy itself.  Now that we will have ipv4-in-ipv6
                 * and ipv6-in-ipv4 tunnels, this is no longer true.
                 */
                if (!ut[i].family)
                        ut[i].family = family;

                switch (ut[i].mode) {
                case XFRM_MODE_TUNNEL:
                case XFRM_MODE_BEET:
                        break;
                default:
                        if (ut[i].family != prev_family)
                                return -EINVAL;
                        break;
                }
                if (ut[i].mode >= XFRM_MODE_MAX)
                        return -EINVAL;

                prev_family = ut[i].family;

                switch (ut[i].family) {
                case AF_INET:
                        break;
#if IS_ENABLED(CONFIG_IPV6)
                case AF_INET6:
                        break;
#endif
                default:
                        return -EINVAL;
                }

                if (!xfrm_id_proto_valid(ut[i].id.proto))
                        return -EINVAL;
        }

        return 0;
}

static int copy_from_user_tmpl(struct xfrm_policy *pol, struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_TMPL];

        if (!rt) {
                pol->xfrm_nr = 0;
        } else {
                struct xfrm_user_tmpl *utmpl = nla_data(rt);
                int nr = nla_len(rt) / sizeof(*utmpl);
                int err;

                err = validate_tmpl(nr, utmpl, pol->family);
                if (err)
                        return err;

                copy_templates(pol, utmpl, nr);
        }
        return 0;
}

static int copy_from_user_policy_type(u8 *tp, struct nlattr **attrs)
{
        struct nlattr *rt = attrs[XFRMA_POLICY_TYPE];
        struct xfrm_userpolicy_type *upt;
        u8 type = XFRM_POLICY_TYPE_MAIN;
        int err;

        if (rt) {
                upt = nla_data(rt);
                type = upt->type;
        }

        err = verify_policy_type(type);
        if (err)
                return err;

        *tp = type;
        return 0;
}

static void copy_from_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p)
{
        xp->priority = p->priority;
        xp->index = p->index;
        memcpy(&xp->selector, &p->sel, sizeof(xp->selector));
        memcpy(&xp->lft, &p->lft, sizeof(xp->lft));
        xp->action = p->action;
        xp->flags = p->flags;
        xp->family = p->sel.family;
        /* XXX xp->share = p->share; */
}

static void copy_to_user_policy(struct xfrm_policy *xp, struct xfrm_userpolicy_info *p, int dir)
{
        memset(p, 0, sizeof(*p));
        memcpy(&p->sel, &xp->selector, sizeof(p->sel));
        memcpy(&p->lft, &xp->lft, sizeof(p->lft));
        memcpy(&p->curlft, &xp->curlft, sizeof(p->curlft));
        p->priority = xp->priority;
        p->index = xp->index;
        p->sel.family = xp->family;
        p->dir = dir;
        p->action = xp->action;
        p->flags = xp->flags;
        p->share = XFRM_SHARE_ANY; /* XXX xp->share */
}

static struct xfrm_policy *xfrm_policy_construct(struct net *net, struct xfrm_userpolicy_info *p, struct nlattr **attrs, int *errp)
{
        struct xfrm_policy *xp = xfrm_policy_alloc(net, GFP_KERNEL);
        int err;

        if (!xp) {
                *errp = -ENOMEM;
                return NULL;
        }

        copy_from_user_policy(xp, p);

        err = copy_from_user_policy_type(&xp->type, attrs);
        if (err)
                goto error;

        if (!(err = copy_from_user_tmpl(xp, attrs)))
                err = copy_from_user_sec_ctx(xp, attrs);
        if (err)
                goto error;

        xfrm_mark_get(attrs, &xp->mark);

        if (attrs[XFRMA_IF_ID])
                xp->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);

        return xp;
 error:
        *errp = err;
        xp->walk.dead = 1;
        xfrm_policy_destroy(xp);
        return NULL;
}

static int xfrm_add_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_userpolicy_info *p = nlmsg_data(nlh);
        struct xfrm_policy *xp;
        struct km_event c;
        int err;
        int excl;

        err = verify_newpolicy_info(p);
        if (err)
                return err;
        err = verify_sec_ctx_len(attrs);
        if (err)
                return err;

        xp = xfrm_policy_construct(net, p, attrs, &err);
        if (!xp)
                return err;

        /* shouldn't excl be based on nlh flags??
         * Aha! this is anti-netlink really i.e  more pfkey derived
         * in netlink excl is a flag and you wouldnt need
         * a type XFRM_MSG_UPDPOLICY - JHS */
        excl = nlh->nlmsg_type == XFRM_MSG_NEWPOLICY;
        err = xfrm_policy_insert(p->dir, xp, excl);
        xfrm_audit_policy_add(xp, err ? 0 : 1, true);

        if (err) {
                security_xfrm_policy_free(xp->security);
                kfree(xp);
                return err;
        }

        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        km_policy_notify(xp, p->dir, &c);

        xfrm_pol_put(xp);

        return 0;
}

static int copy_to_user_tmpl(struct xfrm_policy *xp, struct sk_buff *skb)
{
        struct xfrm_user_tmpl vec[XFRM_MAX_DEPTH];
        int i;

        if (xp->xfrm_nr == 0)
                return 0;

        for (i = 0; i < xp->xfrm_nr; i++) {
                struct xfrm_user_tmpl *up = &vec[i];
                struct xfrm_tmpl *kp = &xp->xfrm_vec[i];

                memset(up, 0, sizeof(*up));
                memcpy(&up->id, &kp->id, sizeof(up->id));
                up->family = kp->encap_family;
                memcpy(&up->saddr, &kp->saddr, sizeof(up->saddr));
                up->reqid = kp->reqid;
                up->mode = kp->mode;
                up->share = kp->share;
                up->optional = kp->optional;
                up->aalgos = kp->aalgos;
                up->ealgos = kp->ealgos;
                up->calgos = kp->calgos;
        }

        return nla_put(skb, XFRMA_TMPL,
                       sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr, vec);
}

static inline int copy_to_user_state_sec_ctx(struct xfrm_state *x, struct sk_buff *skb)
{
        if (x->security) {
                return copy_sec_ctx(x->security, skb);
        }
        return 0;
}

static inline int copy_to_user_sec_ctx(struct xfrm_policy *xp, struct sk_buff *skb)
{
        if (xp->security)
                return copy_sec_ctx(xp->security, skb);
        return 0;
}
static inline unsigned int userpolicy_type_attrsize(void)
{
#ifdef CONFIG_XFRM_SUB_POLICY
        return nla_total_size(sizeof(struct xfrm_userpolicy_type));
#else
        return 0;
#endif
}

#ifdef CONFIG_XFRM_SUB_POLICY
static int copy_to_user_policy_type(u8 type, struct sk_buff *skb)
{
        struct xfrm_userpolicy_type upt;

        /* Sadly there are two holes in struct xfrm_userpolicy_type */
        memset(&upt, 0, sizeof(upt));
        upt.type = type;

        return nla_put(skb, XFRMA_POLICY_TYPE, sizeof(upt), &upt);
}

#else
static inline int copy_to_user_policy_type(u8 type, struct sk_buff *skb)
{
        return 0;
}
#endif

static int dump_one_policy(struct xfrm_policy *xp, int dir, int count, void *ptr)
{
        struct xfrm_dump_info *sp = ptr;
        struct xfrm_userpolicy_info *p;
        struct sk_buff *in_skb = sp->in_skb;
        struct sk_buff *skb = sp->out_skb;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, sp->nlmsg_seq,
                        XFRM_MSG_NEWPOLICY, sizeof(*p), sp->nlmsg_flags);
        if (nlh == NULL)
                return -EMSGSIZE;

        p = nlmsg_data(nlh);
        copy_to_user_policy(xp, p, dir);
        err = copy_to_user_tmpl(xp, skb);
        if (!err)
                err = copy_to_user_sec_ctx(xp, skb);
        if (!err)
                err = copy_to_user_policy_type(xp->type, skb);
        if (!err)
                err = xfrm_mark_put(skb, &xp->mark);
        if (!err)
                err = xfrm_if_id_put(skb, xp->if_id);
        if (err) {
                nlmsg_cancel(skb, nlh);
                return err;
        }
        nlmsg_end(skb, nlh);
        return 0;
}

static int xfrm_dump_policy_done(struct netlink_callback *cb)
{
        struct xfrm_policy_walk *walk = (struct xfrm_policy_walk *)cb->args;
        struct net *net = sock_net(cb->skb->sk);

        xfrm_policy_walk_done(walk, net);
        return 0;
}

static int xfrm_dump_policy_start(struct netlink_callback *cb)
{
        struct xfrm_policy_walk *walk = (struct xfrm_policy_walk *)cb->args;

        BUILD_BUG_ON(sizeof(*walk) > sizeof(cb->args));

        xfrm_policy_walk_init(walk, XFRM_POLICY_TYPE_ANY);
        return 0;
}

static int xfrm_dump_policy(struct sk_buff *skb, struct netlink_callback *cb)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_policy_walk *walk = (struct xfrm_policy_walk *)cb->args;
        struct xfrm_dump_info info;

        info.in_skb = cb->skb;
        info.out_skb = skb;
        info.nlmsg_seq = cb->nlh->nlmsg_seq;
        info.nlmsg_flags = NLM_F_MULTI;

        (void) xfrm_policy_walk(net, walk, dump_one_policy, &info);

        return skb->len;
}

static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
                                          struct xfrm_policy *xp,
                                          int dir, u32 seq)
{
        struct xfrm_dump_info info;
        struct sk_buff *skb;
        int err;

        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
        if (!skb)
                return ERR_PTR(-ENOMEM);

        info.in_skb = in_skb;
        info.out_skb = skb;
        info.nlmsg_seq = seq;
        info.nlmsg_flags = 0;

        err = dump_one_policy(xp, dir, 0, &info);
        if (err) {
                kfree_skb(skb);
                return ERR_PTR(err);
        }

        return skb;
}

static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_policy *xp;
        struct xfrm_userpolicy_id *p;
        u8 type = XFRM_POLICY_TYPE_MAIN;
        int err;
        struct km_event c;
        int delete;
        struct xfrm_mark m;
        u32 if_id = 0;

        p = nlmsg_data(nlh);
        delete = nlh->nlmsg_type == XFRM_MSG_DELPOLICY;

        err = copy_from_user_policy_type(&type, attrs);
        if (err)
                return err;

        err = verify_policy_dir(p->dir);
        if (err)
                return err;

        if (attrs[XFRMA_IF_ID])
                if_id = nla_get_u32(attrs[XFRMA_IF_ID]);

        xfrm_mark_get(attrs, &m);

        if (p->index)
                xp = xfrm_policy_byid(net, &m, if_id, type, p->dir,
                                      p->index, delete, &err);
        else {
                struct nlattr *rt = attrs[XFRMA_SEC_CTX];
                struct xfrm_sec_ctx *ctx;

                err = verify_sec_ctx_len(attrs);
                if (err)
                        return err;

                ctx = NULL;
                if (rt) {
                        struct xfrm_user_sec_ctx *uctx = nla_data(rt);

                        err = security_xfrm_policy_alloc(&ctx, uctx, GFP_KERNEL);
                        if (err)
                                return err;
                }
                xp = xfrm_policy_bysel_ctx(net, &m, if_id, type, p->dir,
                                           &p->sel, ctx, delete, &err);
                security_xfrm_policy_free(ctx);
        }
        if (xp == NULL)
                return -ENOENT;

        if (!delete) {
                struct sk_buff *resp_skb;

                resp_skb = xfrm_policy_netlink(skb, xp, p->dir, nlh->nlmsg_seq);
                if (IS_ERR(resp_skb)) {
                        err = PTR_ERR(resp_skb);
                } else {
                        err = nlmsg_unicast(net->xfrm.nlsk, resp_skb,
                                            NETLINK_CB(skb).portid);
                }
        } else {
                xfrm_audit_policy_delete(xp, err ? 0 : 1, true);

                if (err != 0)
                        goto out;

                c.data.byid = p->index;
                c.event = nlh->nlmsg_type;
                c.seq = nlh->nlmsg_seq;
                c.portid = nlh->nlmsg_pid;
                km_policy_notify(xp, p->dir, &c);
        }

out:
        xfrm_pol_put(xp);
        return err;
}

static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct km_event c;
        struct xfrm_usersa_flush *p = nlmsg_data(nlh);
        int err;

        err = xfrm_state_flush(net, p->proto, true, false);
        if (err) {
                if (err == -ESRCH) /* empty table */
                        return 0;
                return err;
        }
        c.data.proto = p->proto;
        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        c.net = net;
        km_state_notify(NULL, &c);

        return 0;
}

static inline unsigned int xfrm_aevent_msgsize(struct xfrm_state *x)
{
        unsigned int replay_size = x->replay_esn ?
                              xfrm_replay_state_esn_len(x->replay_esn) :
                              sizeof(struct xfrm_replay_state);

        return NLMSG_ALIGN(sizeof(struct xfrm_aevent_id))
               + nla_total_size(replay_size)
               + nla_total_size_64bit(sizeof(struct xfrm_lifetime_cur))
               + nla_total_size(sizeof(struct xfrm_mark))
               + nla_total_size(4) /* XFRM_AE_RTHR */
               + nla_total_size(4); /* XFRM_AE_ETHR */
}

static int build_aevent(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c)
{
        struct xfrm_aevent_id *id;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, c->portid, c->seq, XFRM_MSG_NEWAE, sizeof(*id), 0);
        if (nlh == NULL)
                return -EMSGSIZE;

        id = nlmsg_data(nlh);
        memset(&id->sa_id, 0, sizeof(id->sa_id));
        memcpy(&id->sa_id.daddr, &x->id.daddr, sizeof(x->id.daddr));
        id->sa_id.spi = x->id.spi;
        id->sa_id.family = x->props.family;
        id->sa_id.proto = x->id.proto;
        memcpy(&id->saddr, &x->props.saddr, sizeof(x->props.saddr));
        id->reqid = x->props.reqid;
        id->flags = c->data.aevent;

        if (x->replay_esn) {
                err = nla_put(skb, XFRMA_REPLAY_ESN_VAL,
                              xfrm_replay_state_esn_len(x->replay_esn),
                              x->replay_esn);
        } else {
                err = nla_put(skb, XFRMA_REPLAY_VAL, sizeof(x->replay),
                              &x->replay);
        }
        if (err)
                goto out_cancel;
        err = nla_put_64bit(skb, XFRMA_LTIME_VAL, sizeof(x->curlft), &x->curlft,
                            XFRMA_PAD);
        if (err)
                goto out_cancel;

        if (id->flags & XFRM_AE_RTHR) {
                err = nla_put_u32(skb, XFRMA_REPLAY_THRESH, x->replay_maxdiff);
                if (err)
                        goto out_cancel;
        }
        if (id->flags & XFRM_AE_ETHR) {
                err = nla_put_u32(skb, XFRMA_ETIMER_THRESH,
                                  x->replay_maxage * 10 / HZ);
                if (err)
                        goto out_cancel;
        }
        err = xfrm_mark_put(skb, &x->mark);
        if (err)
                goto out_cancel;

        err = xfrm_if_id_put(skb, x->if_id);
        if (err)
                goto out_cancel;

        nlmsg_end(skb, nlh);
        return 0;

out_cancel:
        nlmsg_cancel(skb, nlh);
        return err;
}

static int xfrm_get_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state *x;
        struct sk_buff *r_skb;
        int err;
        struct km_event c;
        u32 mark;
        struct xfrm_mark m;
        struct xfrm_aevent_id *p = nlmsg_data(nlh);
        struct xfrm_usersa_id *id = &p->sa_id;

        mark = xfrm_mark_get(attrs, &m);

        x = xfrm_state_lookup(net, mark, &id->daddr, id->spi, id->proto, id->family);
        if (x == NULL)
                return -ESRCH;

        r_skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC);
        if (r_skb == NULL) {
                xfrm_state_put(x);
                return -ENOMEM;
        }

        /*
         * XXX: is this lock really needed - none of the other
         * gets lock (the concern is things getting updated
         * while we are still reading) - jhs
        */
        spin_lock_bh(&x->lock);
        c.data.aevent = p->flags;
        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;

        err = build_aevent(r_skb, x, &c);
        BUG_ON(err < 0);

        err = nlmsg_unicast(net->xfrm.nlsk, r_skb, NETLINK_CB(skb).portid);
        spin_unlock_bh(&x->lock);
        xfrm_state_put(x);
        return err;
}

static int xfrm_new_ae(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state *x;
        struct km_event c;
        int err = -EINVAL;
        u32 mark = 0;
        struct xfrm_mark m;
        struct xfrm_aevent_id *p = nlmsg_data(nlh);
        struct nlattr *rp = attrs[XFRMA_REPLAY_VAL];
        struct nlattr *re = attrs[XFRMA_REPLAY_ESN_VAL];
        struct nlattr *lt = attrs[XFRMA_LTIME_VAL];
        struct nlattr *et = attrs[XFRMA_ETIMER_THRESH];
        struct nlattr *rt = attrs[XFRMA_REPLAY_THRESH];

        if (!lt && !rp && !re && !et && !rt)
                return err;

        /* pedantic mode - thou shalt sayeth replaceth */
        if (!(nlh->nlmsg_flags&NLM_F_REPLACE))
                return err;

        mark = xfrm_mark_get(attrs, &m);

        x = xfrm_state_lookup(net, mark, &p->sa_id.daddr, p->sa_id.spi, p->sa_id.proto, p->sa_id.family);
        if (x == NULL)
                return -ESRCH;

        if (x->km.state != XFRM_STATE_VALID)
                goto out;

        err = xfrm_replay_verify_len(x->replay_esn, re);
        if (err)
                goto out;

        spin_lock_bh(&x->lock);
        xfrm_update_ae_params(x, attrs, 1);
        spin_unlock_bh(&x->lock);

        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        c.data.aevent = XFRM_AE_CU;
        km_state_notify(x, &c);
        err = 0;
out:
        xfrm_state_put(x);
        return err;
}

static int xfrm_flush_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct km_event c;
        u8 type = XFRM_POLICY_TYPE_MAIN;
        int err;

        err = copy_from_user_policy_type(&type, attrs);
        if (err)
                return err;

        err = xfrm_policy_flush(net, type, true);
        if (err) {
                if (err == -ESRCH) /* empty table */
                        return 0;
                return err;
        }

        c.data.type = type;
        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;
        c.portid = nlh->nlmsg_pid;
        c.net = net;
        km_policy_notify(NULL, 0, &c);
        return 0;
}

static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_policy *xp;
        struct xfrm_user_polexpire *up = nlmsg_data(nlh);
        struct xfrm_userpolicy_info *p = &up->pol;
        u8 type = XFRM_POLICY_TYPE_MAIN;
        int err = -ENOENT;
        struct xfrm_mark m;
        u32 if_id = 0;

        err = copy_from_user_policy_type(&type, attrs);
        if (err)
                return err;

        err = verify_policy_dir(p->dir);
        if (err)
                return err;

        if (attrs[XFRMA_IF_ID])
                if_id = nla_get_u32(attrs[XFRMA_IF_ID]);

        xfrm_mark_get(attrs, &m);

        if (p->index)
                xp = xfrm_policy_byid(net, &m, if_id, type, p->dir, p->index,
                                      0, &err);
        else {
                struct nlattr *rt = attrs[XFRMA_SEC_CTX];
                struct xfrm_sec_ctx *ctx;

                err = verify_sec_ctx_len(attrs);
                if (err)
                        return err;

                ctx = NULL;
                if (rt) {
                        struct xfrm_user_sec_ctx *uctx = nla_data(rt);

                        err = security_xfrm_policy_alloc(&ctx, uctx, GFP_KERNEL);
                        if (err)
                                return err;
                }
                xp = xfrm_policy_bysel_ctx(net, &m, if_id, type, p->dir,
                                           &p->sel, ctx, 0, &err);
                security_xfrm_policy_free(ctx);
        }
        if (xp == NULL)
                return -ENOENT;

        if (unlikely(xp->walk.dead))
                goto out;

        err = 0;
        if (up->hard) {
                xfrm_policy_delete(xp, p->dir);
                xfrm_audit_policy_delete(xp, 1, true);
        }
        km_policy_expired(xp, p->dir, up->hard, nlh->nlmsg_pid);

out:
        xfrm_pol_put(xp);
        return err;
}

static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_state *x;
        int err;
        struct xfrm_user_expire *ue = nlmsg_data(nlh);
        struct xfrm_usersa_info *p = &ue->state;
        struct xfrm_mark m;
        u32 mark = xfrm_mark_get(attrs, &m);

        x = xfrm_state_lookup(net, mark, &p->id.daddr, p->id.spi, p->id.proto, p->family);

        err = -ENOENT;
        if (x == NULL)
                return err;

        spin_lock_bh(&x->lock);
        err = -EINVAL;
        if (x->km.state != XFRM_STATE_VALID)
                goto out;
        km_state_expired(x, ue->hard, nlh->nlmsg_pid);

        if (ue->hard) {
                __xfrm_state_delete(x);
                xfrm_audit_state_delete(x, 1, true);
        }
        err = 0;
out:
        spin_unlock_bh(&x->lock);
        xfrm_state_put(x);
        return err;
}

static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
                struct nlattr **attrs)
{
        struct net *net = sock_net(skb->sk);
        struct xfrm_policy *xp;
        struct xfrm_user_tmpl *ut;
        int i;
        struct nlattr *rt = attrs[XFRMA_TMPL];
        struct xfrm_mark mark;

        struct xfrm_user_acquire *ua = nlmsg_data(nlh);
        struct xfrm_state *x = xfrm_state_alloc(net);
        int err = -ENOMEM;

        if (!x)
                goto nomem;

        xfrm_mark_get(attrs, &mark);

        err = verify_newpolicy_info(&ua->policy);
        if (err)
                goto free_state;
        err = verify_sec_ctx_len(attrs);
        if (err)
                goto free_state;

        /*   build an XP */
        xp = xfrm_policy_construct(net, &ua->policy, attrs, &err);
        if (!xp)
                goto free_state;

        memcpy(&x->id, &ua->id, sizeof(ua->id));
        memcpy(&x->props.saddr, &ua->saddr, sizeof(ua->saddr));
        memcpy(&x->sel, &ua->sel, sizeof(ua->sel));
        xp->mark.m = x->mark.m = mark.m;
        xp->mark.v = x->mark.v = mark.v;
        ut = nla_data(rt);
        /* extract the templates and for each call km_key */
        for (i = 0; i < xp->xfrm_nr; i++, ut++) {
                struct xfrm_tmpl *t = &xp->xfrm_vec[i];
                memcpy(&x->id, &t->id, sizeof(x->id));
                x->props.mode = t->mode;
                x->props.reqid = t->reqid;
                x->props.family = ut->family;
                t->aalgos = ua->aalgos;
                t->ealgos = ua->ealgos;
                t->calgos = ua->calgos;
                err = km_query(x, t, xp);

        }

        xfrm_state_free(x);
        kfree(xp);

        return 0;

free_state:
        xfrm_state_free(x);
nomem:
        return err;
}

#ifdef CONFIG_XFRM_MIGRATE
static int copy_from_user_migrate(struct xfrm_migrate *ma,
                                  struct xfrm_kmaddress *k,
                                  struct nlattr **attrs, int *num)
{
        struct nlattr *rt = attrs[XFRMA_MIGRATE];
        struct xfrm_user_migrate *um;
        int i, num_migrate;

        if (k != NULL) {
                struct xfrm_user_kmaddress *uk;

                uk = nla_data(attrs[XFRMA_KMADDRESS]);
                memcpy(&k->local, &uk->local, sizeof(k->local));
                memcpy(&k->remote, &uk->remote, sizeof(k->remote));
                k->family = uk->family;
                k->reserved = uk->reserved;
        }

        um = nla_data(rt);
        num_migrate = nla_len(rt) / sizeof(*um);

        if (num_migrate <= 0 || num_migrate > XFRM_MAX_DEPTH)
                return -EINVAL;

        for (i = 0; i < num_migrate; i++, um++, ma++) {
                memcpy(&ma->old_daddr, &um->old_daddr, sizeof(ma->old_daddr));
                memcpy(&ma->old_saddr, &um->old_saddr, sizeof(ma->old_saddr));
                memcpy(&ma->new_daddr, &um->new_daddr, sizeof(ma->new_daddr));
                memcpy(&ma->new_saddr, &um->new_saddr, sizeof(ma->new_saddr));

                ma->proto = um->proto;
                ma->mode = um->mode;
                ma->reqid = um->reqid;

                ma->old_family = um->old_family;
                ma->new_family = um->new_family;
        }

        *num = i;
        return 0;
}

static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
                           struct nlattr **attrs)
{
        struct xfrm_userpolicy_id *pi = nlmsg_data(nlh);
        struct xfrm_migrate m[XFRM_MAX_DEPTH];
        struct xfrm_kmaddress km, *kmp;
        u8 type;
        int err;
        int n = 0;
        struct net *net = sock_net(skb->sk);
        struct xfrm_encap_tmpl  *encap = NULL;

        if (attrs[XFRMA_MIGRATE] == NULL)
                return -EINVAL;

        kmp = attrs[XFRMA_KMADDRESS] ? &km : NULL;

        err = copy_from_user_policy_type(&type, attrs);
        if (err)
                return err;

        err = copy_from_user_migrate((struct xfrm_migrate *)m, kmp, attrs, &n);
        if (err)
                return err;

        if (!n)
                return 0;

        if (attrs[XFRMA_ENCAP]) {
                encap = kmemdup(nla_data(attrs[XFRMA_ENCAP]),
                                sizeof(*encap), GFP_KERNEL);
                if (!encap)
                        return 0;
        }

        err = xfrm_migrate(&pi->sel, pi->dir, type, m, n, kmp, net, encap);

        kfree(encap);

        return err;
}
#else
static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
                           struct nlattr **attrs)
{
        return -ENOPROTOOPT;
}
#endif

#ifdef CONFIG_XFRM_MIGRATE
static int copy_to_user_migrate(const struct xfrm_migrate *m, struct sk_buff *skb)
{
        struct xfrm_user_migrate um;

        memset(&um, 0, sizeof(um));
        um.proto = m->proto;
        um.mode = m->mode;
        um.reqid = m->reqid;
        um.old_family = m->old_family;
        memcpy(&um.old_daddr, &m->old_daddr, sizeof(um.old_daddr));
        memcpy(&um.old_saddr, &m->old_saddr, sizeof(um.old_saddr));
        um.new_family = m->new_family;
        memcpy(&um.new_daddr, &m->new_daddr, sizeof(um.new_daddr));
        memcpy(&um.new_saddr, &m->new_saddr, sizeof(um.new_saddr));

        return nla_put(skb, XFRMA_MIGRATE, sizeof(um), &um);
}

static int copy_to_user_kmaddress(const struct xfrm_kmaddress *k, struct sk_buff *skb)
{
        struct xfrm_user_kmaddress uk;

        memset(&uk, 0, sizeof(uk));
        uk.family = k->family;
        uk.reserved = k->reserved;
        memcpy(&uk.local, &k->local, sizeof(uk.local));
        memcpy(&uk.remote, &k->remote, sizeof(uk.remote));

        return nla_put(skb, XFRMA_KMADDRESS, sizeof(uk), &uk);
}

static inline unsigned int xfrm_migrate_msgsize(int num_migrate, int with_kma,
                                                int with_encp)
{
        return NLMSG_ALIGN(sizeof(struct xfrm_userpolicy_id))
              + (with_kma ? nla_total_size(sizeof(struct xfrm_kmaddress)) : 0)
              + (with_encp ? nla_total_size(sizeof(struct xfrm_encap_tmpl)) : 0)
              + nla_total_size(sizeof(struct xfrm_user_migrate) * num_migrate)
              + userpolicy_type_attrsize();
}

static int build_migrate(struct sk_buff *skb, const struct xfrm_migrate *m,
                         int num_migrate, const struct xfrm_kmaddress *k,
                         const struct xfrm_selector *sel,
                         const struct xfrm_encap_tmpl *encap, u8 dir, u8 type)
{
        const struct xfrm_migrate *mp;
        struct xfrm_userpolicy_id *pol_id;
        struct nlmsghdr *nlh;
        int i, err;

        nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_MIGRATE, sizeof(*pol_id), 0);
        if (nlh == NULL)
                return -EMSGSIZE;

        pol_id = nlmsg_data(nlh);
        /* copy data from selector, dir, and type to the pol_id */
        memset(pol_id, 0, sizeof(*pol_id));
        memcpy(&pol_id->sel, sel, sizeof(pol_id->sel));
        pol_id->dir = dir;

        if (k != NULL) {
                err = copy_to_user_kmaddress(k, skb);
                if (err)
                        goto out_cancel;
        }
        if (encap) {
                err = nla_put(skb, XFRMA_ENCAP, sizeof(*encap), encap);
                if (err)
                        goto out_cancel;
        }
        err = copy_to_user_policy_type(type, skb);
        if (err)
                goto out_cancel;
        for (i = 0, mp = m ; i < num_migrate; i++, mp++) {
                err = copy_to_user_migrate(mp, skb);
                if (err)
                        goto out_cancel;
        }

        nlmsg_end(skb, nlh);
        return 0;

out_cancel:
        nlmsg_cancel(skb, nlh);
        return err;
}

static int xfrm_send_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
                             const struct xfrm_migrate *m, int num_migrate,
                             const struct xfrm_kmaddress *k,
                             const struct xfrm_encap_tmpl *encap)
{
        struct net *net = &init_net;
        struct sk_buff *skb;
        int err;

        skb = nlmsg_new(xfrm_migrate_msgsize(num_migrate, !!k, !!encap),
                        GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        /* build migrate */
        err = build_migrate(skb, m, num_migrate, k, sel, encap, dir, type);
        BUG_ON(err < 0);

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_MIGRATE);
}
#else
static int xfrm_send_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
                             const struct xfrm_migrate *m, int num_migrate,
                             const struct xfrm_kmaddress *k,
                             const struct xfrm_encap_tmpl *encap)
{
        return -ENOPROTOOPT;
}
#endif

#define XMSGSIZE(type) sizeof(struct type)

static const int xfrm_msg_min[XFRM_NR_MSGTYPES] = {
        [XFRM_MSG_NEWSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_info),
        [XFRM_MSG_DELSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_id),
        [XFRM_MSG_GETSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_id),
        [XFRM_MSG_NEWPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_info),
        [XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
        [XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
        [XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userspi_info),
        [XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_acquire),
        [XFRM_MSG_EXPIRE      - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_expire),
        [XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_info),
        [XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_info),
        [XFRM_MSG_POLEXPIRE   - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_polexpire),
        [XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_usersa_flush),
        [XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = 0,
        [XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
        [XFRM_MSG_GETAE       - XFRM_MSG_BASE] = XMSGSIZE(xfrm_aevent_id),
        [XFRM_MSG_REPORT      - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_report),
        [XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = XMSGSIZE(xfrm_userpolicy_id),
        [XFRM_MSG_GETSADINFO  - XFRM_MSG_BASE] = sizeof(u32),
        [XFRM_MSG_NEWSPDINFO  - XFRM_MSG_BASE] = sizeof(u32),
        [XFRM_MSG_GETSPDINFO  - XFRM_MSG_BASE] = sizeof(u32),
};

#undef XMSGSIZE

static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = {
        [XFRMA_SA]              = { .len = sizeof(struct xfrm_usersa_info)},
        [XFRMA_POLICY]          = { .len = sizeof(struct xfrm_userpolicy_info)},
        [XFRMA_LASTUSED]        = { .type = NLA_U64},
        [XFRMA_ALG_AUTH_TRUNC]  = { .len = sizeof(struct xfrm_algo_auth)},
        [XFRMA_ALG_AEAD]        = { .len = sizeof(struct xfrm_algo_aead) },
        [XFRMA_ALG_AUTH]        = { .len = sizeof(struct xfrm_algo) },
        [XFRMA_ALG_CRYPT]       = { .len = sizeof(struct xfrm_algo) },
        [XFRMA_ALG_COMP]        = { .len = sizeof(struct xfrm_algo) },
        [XFRMA_ENCAP]           = { .len = sizeof(struct xfrm_encap_tmpl) },
        [XFRMA_TMPL]            = { .len = sizeof(struct xfrm_user_tmpl) },
        [XFRMA_SEC_CTX]         = { .len = sizeof(struct xfrm_sec_ctx) },
        [XFRMA_LTIME_VAL]       = { .len = sizeof(struct xfrm_lifetime_cur) },
        [XFRMA_REPLAY_VAL]      = { .len = sizeof(struct xfrm_replay_state) },
        [XFRMA_REPLAY_THRESH]   = { .type = NLA_U32 },
        [XFRMA_ETIMER_THRESH]   = { .type = NLA_U32 },
        [XFRMA_SRCADDR]         = { .len = sizeof(xfrm_address_t) },
        [XFRMA_COADDR]          = { .len = sizeof(xfrm_address_t) },
        [XFRMA_POLICY_TYPE]     = { .len = sizeof(struct xfrm_userpolicy_type)},
        [XFRMA_MIGRATE]         = { .len = sizeof(struct xfrm_user_migrate) },
        [XFRMA_KMADDRESS]       = { .len = sizeof(struct xfrm_user_kmaddress) },
        [XFRMA_MARK]            = { .len = sizeof(struct xfrm_mark) },
        [XFRMA_TFCPAD]          = { .type = NLA_U32 },
        [XFRMA_REPLAY_ESN_VAL]  = { .len = sizeof(struct xfrm_replay_state_esn) },
        [XFRMA_SA_EXTRA_FLAGS]  = { .type = NLA_U32 },
        [XFRMA_PROTO]           = { .type = NLA_U8 },
        [XFRMA_ADDRESS_FILTER]  = { .len = sizeof(struct xfrm_address_filter) },
        [XFRMA_OFFLOAD_DEV]     = { .len = sizeof(struct xfrm_user_offload) },
        [XFRMA_SET_MARK]        = { .type = NLA_U32 },
        [XFRMA_SET_MARK_MASK]   = { .type = NLA_U32 },
        [XFRMA_IF_ID]           = { .type = NLA_U32 },
};

static const struct nla_policy xfrma_spd_policy[XFRMA_SPD_MAX+1] = {
        [XFRMA_SPD_IPV4_HTHRESH] = { .len = sizeof(struct xfrmu_spdhthresh) },
        [XFRMA_SPD_IPV6_HTHRESH] = { .len = sizeof(struct xfrmu_spdhthresh) },
};

static const struct xfrm_link {
        int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
        int (*start)(struct netlink_callback *);
        int (*dump)(struct sk_buff *, struct netlink_callback *);
        int (*done)(struct netlink_callback *);
        const struct nla_policy *nla_pol;
        int nla_max;
} xfrm_dispatch[XFRM_NR_MSGTYPES] = {
        [XFRM_MSG_NEWSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
        [XFRM_MSG_DELSA       - XFRM_MSG_BASE] = { .doit = xfrm_del_sa        },
        [XFRM_MSG_GETSA       - XFRM_MSG_BASE] = { .doit = xfrm_get_sa,
                                                   .dump = xfrm_dump_sa,
                                                   .done = xfrm_dump_sa_done  },
        [XFRM_MSG_NEWPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
        [XFRM_MSG_DELPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy    },
        [XFRM_MSG_GETPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_get_policy,
                                                   .start = xfrm_dump_policy_start,
                                                   .dump = xfrm_dump_policy,
                                                   .done = xfrm_dump_policy_done },
        [XFRM_MSG_ALLOCSPI    - XFRM_MSG_BASE] = { .doit = xfrm_alloc_userspi },
        [XFRM_MSG_ACQUIRE     - XFRM_MSG_BASE] = { .doit = xfrm_add_acquire   },
        [XFRM_MSG_EXPIRE      - XFRM_MSG_BASE] = { .doit = xfrm_add_sa_expire },
        [XFRM_MSG_UPDPOLICY   - XFRM_MSG_BASE] = { .doit = xfrm_add_policy    },
        [XFRM_MSG_UPDSA       - XFRM_MSG_BASE] = { .doit = xfrm_add_sa        },
        [XFRM_MSG_POLEXPIRE   - XFRM_MSG_BASE] = { .doit = xfrm_add_pol_expire},
        [XFRM_MSG_FLUSHSA     - XFRM_MSG_BASE] = { .doit = xfrm_flush_sa      },
        [XFRM_MSG_FLUSHPOLICY - XFRM_MSG_BASE] = { .doit = xfrm_flush_policy  },
        [XFRM_MSG_NEWAE       - XFRM_MSG_BASE] = { .doit = xfrm_new_ae  },
        [XFRM_MSG_GETAE       - XFRM_MSG_BASE] = { .doit = xfrm_get_ae  },
        [XFRM_MSG_MIGRATE     - XFRM_MSG_BASE] = { .doit = xfrm_do_migrate    },
        [XFRM_MSG_GETSADINFO  - XFRM_MSG_BASE] = { .doit = xfrm_get_sadinfo   },
        [XFRM_MSG_NEWSPDINFO  - XFRM_MSG_BASE] = { .doit = xfrm_set_spdinfo,
                                                   .nla_pol = xfrma_spd_policy,
                                                   .nla_max = XFRMA_SPD_MAX },
        [XFRM_MSG_GETSPDINFO  - XFRM_MSG_BASE] = { .doit = xfrm_get_spdinfo   },
};

static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
                             struct netlink_ext_ack *extack)
{
        struct net *net = sock_net(skb->sk);
        struct nlattr *attrs[XFRMA_MAX+1];
        const struct xfrm_link *link;
        int type, err;

#ifdef CONFIG_COMPAT
        if (in_compat_syscall())
                return -EOPNOTSUPP;
#endif

        type = nlh->nlmsg_type;
        if (type > XFRM_MSG_MAX)
                return -EINVAL;

        type -= XFRM_MSG_BASE;
        link = &xfrm_dispatch[type];

        /* All operations require privileges, even GET */
        if (!netlink_net_capable(skb, CAP_NET_ADMIN))
                return -EPERM;

        if ((type == (XFRM_MSG_GETSA - XFRM_MSG_BASE) ||
             type == (XFRM_MSG_GETPOLICY - XFRM_MSG_BASE)) &&
            (nlh->nlmsg_flags & NLM_F_DUMP)) {
                if (link->dump == NULL)
                        return -EINVAL;

                {
                        struct netlink_dump_control c = {
                                .start = link->start,
                                .dump = link->dump,
                                .done = link->done,
                        };
                        return netlink_dump_start(net->xfrm.nlsk, skb, nlh, &c);
                }
        }

        err = nlmsg_parse_deprecated(nlh, xfrm_msg_min[type], attrs,
                                     link->nla_max ? : XFRMA_MAX,
                                     link->nla_pol ? : xfrma_policy, extack);
        if (err < 0)
                return err;

        if (link->doit == NULL)
                return -EINVAL;

        return link->doit(skb, nlh, attrs);
}

static void xfrm_netlink_rcv(struct sk_buff *skb)
{
        struct net *net = sock_net(skb->sk);

        mutex_lock(&net->xfrm.xfrm_cfg_mutex);
        netlink_rcv_skb(skb, &xfrm_user_rcv_msg);
        mutex_unlock(&net->xfrm.xfrm_cfg_mutex);
}

static inline unsigned int xfrm_expire_msgsize(void)
{
        return NLMSG_ALIGN(sizeof(struct xfrm_user_expire))
               + nla_total_size(sizeof(struct xfrm_mark));
}

static int build_expire(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c)
{
        struct xfrm_user_expire *ue;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, c->portid, 0, XFRM_MSG_EXPIRE, sizeof(*ue), 0);
        if (nlh == NULL)
                return -EMSGSIZE;

        ue = nlmsg_data(nlh);
        copy_to_user_state(x, &ue->state);
        ue->hard = (c->data.hard != 0) ? 1 : 0;
        /* clear the padding bytes */
        memset(&ue->hard + 1, 0, sizeof(*ue) - offsetofend(typeof(*ue), hard));

        err = xfrm_mark_put(skb, &x->mark);
        if (err)
                return err;

        err = xfrm_if_id_put(skb, x->if_id);
        if (err)
                return err;

        nlmsg_end(skb, nlh);
        return 0;
}

static int xfrm_exp_state_notify(struct xfrm_state *x, const struct km_event *c)
{
        struct net *net = xs_net(x);
        struct sk_buff *skb;

        skb = nlmsg_new(xfrm_expire_msgsize(), GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        if (build_expire(skb, x, c) < 0) {
                kfree_skb(skb);
                return -EMSGSIZE;
        }

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_EXPIRE);
}

static int xfrm_aevent_state_notify(struct xfrm_state *x, const struct km_event *c)
{
        struct net *net = xs_net(x);
        struct sk_buff *skb;
        int err;

        skb = nlmsg_new(xfrm_aevent_msgsize(x), GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        err = build_aevent(skb, x, c);
        BUG_ON(err < 0);

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_AEVENTS);
}

static int xfrm_notify_sa_flush(const struct km_event *c)
{
        struct net *net = c->net;
        struct xfrm_usersa_flush *p;
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        int len = NLMSG_ALIGN(sizeof(struct xfrm_usersa_flush));

        skb = nlmsg_new(len, GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        nlh = nlmsg_put(skb, c->portid, c->seq, XFRM_MSG_FLUSHSA, sizeof(*p), 0);
        if (nlh == NULL) {
                kfree_skb(skb);
                return -EMSGSIZE;
        }

        p = nlmsg_data(nlh);
        p->proto = c->data.proto;

        nlmsg_end(skb, nlh);

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_SA);
}

static inline unsigned int xfrm_sa_len(struct xfrm_state *x)
{
        unsigned int l = 0;
        if (x->aead)
                l += nla_total_size(aead_len(x->aead));
        if (x->aalg) {
                l += nla_total_size(sizeof(struct xfrm_algo) +
                                    (x->aalg->alg_key_len + 7) / 8);
                l += nla_total_size(xfrm_alg_auth_len(x->aalg));
        }
        if (x->ealg)
                l += nla_total_size(xfrm_alg_len(x->ealg));
        if (x->calg)
                l += nla_total_size(sizeof(*x->calg));
        if (x->encap)
                l += nla_total_size(sizeof(*x->encap));
        if (x->tfcpad)
                l += nla_total_size(sizeof(x->tfcpad));
        if (x->replay_esn)
                l += nla_total_size(xfrm_replay_state_esn_len(x->replay_esn));
        else
                l += nla_total_size(sizeof(struct xfrm_replay_state));
        if (x->security)
                l += nla_total_size(sizeof(struct xfrm_user_sec_ctx) +
                                    x->security->ctx_len);
        if (x->coaddr)
                l += nla_total_size(sizeof(*x->coaddr));
        if (x->props.extra_flags)
                l += nla_total_size(sizeof(x->props.extra_flags));
        if (x->xso.dev)
                 l += nla_total_size(sizeof(x->xso));
        if (x->props.output_mark | x->output_mark_mask) {
                l += nla_total_size(sizeof(x->props.output_mark));
                l += nla_total_size(sizeof(x->output_mark_mask));
        }
        if (x->if_id)
                l += nla_total_size(sizeof(x->if_id));

        /* Must count x->lastused as it may become non-zero behind our back. */
        l += nla_total_size_64bit(sizeof(u64));

        return l;
}

static int xfrm_notify_sa(struct xfrm_state *x, const struct km_event *c)
{
        struct net *net = xs_net(x);
        struct xfrm_usersa_info *p;
        struct xfrm_usersa_id *id;
        struct nlmsghdr *nlh;
        struct sk_buff *skb;
        unsigned int len = xfrm_sa_len(x);
        unsigned int headlen;
        int err;

        headlen = sizeof(*p);
        if (c->event == XFRM_MSG_DELSA) {
                len += nla_total_size(headlen);
                headlen = sizeof(*id);
                len += nla_total_size(sizeof(struct xfrm_mark));
        }
        len += NLMSG_ALIGN(headlen);

        skb = nlmsg_new(len, GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        nlh = nlmsg_put(skb, c->portid, c->seq, c->event, headlen, 0);
        err = -EMSGSIZE;
        if (nlh == NULL)
                goto out_free_skb;

        p = nlmsg_data(nlh);
        if (c->event == XFRM_MSG_DELSA) {
                struct nlattr *attr;

                id = nlmsg_data(nlh);
                memset(id, 0, sizeof(*id));
                memcpy(&id->daddr, &x->id.daddr, sizeof(id->daddr));
                id->spi = x->id.spi;
                id->family = x->props.family;
                id->proto = x->id.proto;

                attr = nla_reserve(skb, XFRMA_SA, sizeof(*p));
                err = -EMSGSIZE;
                if (attr == NULL)
                        goto out_free_skb;

                p = nla_data(attr);
        }
        err = copy_to_user_state_extra(x, p, skb);
        if (err)
                goto out_free_skb;

        nlmsg_end(skb, nlh);

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_SA);

out_free_skb:
        kfree_skb(skb);
        return err;
}

static int xfrm_send_state_notify(struct xfrm_state *x, const struct km_event *c)
{

        switch (c->event) {
        case XFRM_MSG_EXPIRE:
                return xfrm_exp_state_notify(x, c);
        case XFRM_MSG_NEWAE:
                return xfrm_aevent_state_notify(x, c);
        case XFRM_MSG_DELSA:
        case XFRM_MSG_UPDSA:
        case XFRM_MSG_NEWSA:
                return xfrm_notify_sa(x, c);
        case XFRM_MSG_FLUSHSA:
                return xfrm_notify_sa_flush(c);
        default:
                printk(KERN_NOTICE "xfrm_user: Unknown SA event %d\n",
                       c->event);
                break;
        }

        return 0;

}

static inline unsigned int xfrm_acquire_msgsize(struct xfrm_state *x,
                                                struct xfrm_policy *xp)
{
        return NLMSG_ALIGN(sizeof(struct xfrm_user_acquire))
               + nla_total_size(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr)
               + nla_total_size(sizeof(struct xfrm_mark))
               + nla_total_size(xfrm_user_sec_ctx_size(x->security))
               + userpolicy_type_attrsize();
}

static int build_acquire(struct sk_buff *skb, struct xfrm_state *x,
                         struct xfrm_tmpl *xt, struct xfrm_policy *xp)
{
        __u32 seq = xfrm_get_acqseq();
        struct xfrm_user_acquire *ua;
        struct nlmsghdr *nlh;
        int err;

        nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_ACQUIRE, sizeof(*ua), 0);
        if (nlh == NULL)
                return -EMSGSIZE;

        ua = nlmsg_data(nlh);
        memcpy(&ua->id, &x->id, sizeof(ua->id));
        memcpy(&ua->saddr, &x->props.saddr, sizeof(ua->saddr));
        memcpy(&ua->sel, &x->sel, sizeof(ua->sel));
        copy_to_user_policy(xp, &ua->policy, XFRM_POLICY_OUT);
        ua->aalgos = xt->aalgos;
        ua->ealgos = xt->ealgos;
        ua->calgos = xt->calgos;
        ua->seq = x->km.seq = seq;

        err = copy_to_user_tmpl(xp, skb);
        if (!err)
                err = copy_to_user_state_sec_ctx(x, skb);
        if (!err)
                err = copy_to_user_policy_type(xp->type, skb);
        if (!err)
                err = xfrm_mark_put(skb, &xp->mark);
        if (!err)
                err = xfrm_if_id_put(skb, xp->if_id);
        if (err) {
                nlmsg_cancel(skb, nlh);
                return err;
        }

        nlmsg_end(skb, nlh);
        return 0;
}

static int xfrm_send_acquire(struct xfrm_state *x, struct xfrm_tmpl *xt,
                             struct xfrm_policy *xp)
{
        struct net *net = xs_net(x);
        struct sk_buff *skb;
        int err;

        skb = nlmsg_new(xfrm_acquire_msgsize(x, xp), GFP_ATOMIC);
        if (skb == NULL)
                return -ENOMEM;

        err = build_acquire(skb, x, xt, xp);
        BUG_ON(err < 0);

        return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_ACQUIRE);
}

/* User gives us xfrm_user_policy_info followed by an array of 0
 * or more templates.
 */
static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt,
                                               u8 *data, int len, int *dir)
{
        struct net *net = sock_net(sk);
        struct xfrm_userpolicy_info *p = (struct xfrm_userpolicy_info *)data;
        struct xfrm_user_tmpl *ut = (struct xfrm_user_tmpl *) (p + 1);
        struct xfrm_policy *xp;
        int nr;