diff options
Diffstat (limited to 'net/xfrm/xfrm_compat.c')
| -rw-r--r-- | net/xfrm/xfrm_compat.c | 675 |
1 files changed, 675 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c new file mode 100644 index 000000000..655fe4ff8 --- /dev/null +++ b/net/xfrm/xfrm_compat.c @@ -0,0 +1,675 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * XFRM compat layer + * Author: Dmitry Safonov <dima@arista.com> + * Based on code and translator idea by: Florian Westphal <fw@strlen.de> + */ +#include <linux/compat.h> +#include <linux/nospec.h> +#include <linux/xfrm.h> +#include <net/xfrm.h> + +struct compat_xfrm_lifetime_cfg { + compat_u64 soft_byte_limit, hard_byte_limit; + compat_u64 soft_packet_limit, hard_packet_limit; + compat_u64 soft_add_expires_seconds, hard_add_expires_seconds; + compat_u64 soft_use_expires_seconds, hard_use_expires_seconds; +}; /* same size on 32bit, but only 4 byte alignment required */ + +struct compat_xfrm_lifetime_cur { + compat_u64 bytes, packets, add_time, use_time; +}; /* same size on 32bit, but only 4 byte alignment required */ + +struct compat_xfrm_userpolicy_info { + struct xfrm_selector sel; + struct compat_xfrm_lifetime_cfg lft; + struct compat_xfrm_lifetime_cur curlft; + __u32 priority, index; + u8 dir, action, flags, share; + /* 4 bytes additional padding on 64bit */ +}; + +struct compat_xfrm_usersa_info { + struct xfrm_selector sel; + struct xfrm_id id; + xfrm_address_t saddr; + struct compat_xfrm_lifetime_cfg lft; + struct compat_xfrm_lifetime_cur curlft; + struct xfrm_stats stats; + __u32 seq, reqid; + u16 family; + u8 mode, replay_window, flags; + /* 4 bytes additional padding on 64bit */ +}; + +struct compat_xfrm_user_acquire { + struct xfrm_id id; + xfrm_address_t saddr; + struct xfrm_selector sel; + struct compat_xfrm_userpolicy_info policy; + /* 4 bytes additional padding on 64bit */ + __u32 aalgos, ealgos, calgos, seq; +}; + +struct compat_xfrm_userspi_info { + struct compat_xfrm_usersa_info info; + /* 4 bytes additional padding on 64bit */ + __u32 min, max; +}; + +struct compat_xfrm_user_expire { + struct compat_xfrm_usersa_info state; + /* 8 bytes additional padding on 64bit */ + u8 hard; +}; + +struct compat_xfrm_user_polexpire { + struct compat_xfrm_userpolicy_info pol; + /* 8 bytes additional padding on 64bit */ + u8 hard; +}; + +#define XMSGSIZE(type) sizeof(struct type) + +static const int compat_msg_min[XFRM_NR_MSGTYPES] = { + [XFRM_MSG_NEWSA - XFRM_MSG_BASE] = XMSGSIZE(compat_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(compat_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(compat_xfrm_userspi_info), + [XFRM_MSG_ACQUIRE - XFRM_MSG_BASE] = XMSGSIZE(compat_xfrm_user_acquire), + [XFRM_MSG_EXPIRE - XFRM_MSG_BASE] = XMSGSIZE(compat_xfrm_user_expire), + [XFRM_MSG_UPDPOLICY - XFRM_MSG_BASE] = XMSGSIZE(compat_xfrm_userpolicy_info), + [XFRM_MSG_UPDSA - XFRM_MSG_BASE] = XMSGSIZE(compat_xfrm_usersa_info), + [XFRM_MSG_POLEXPIRE - XFRM_MSG_BASE] = XMSGSIZE(compat_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_NEWSADINFO - XFRM_MSG_BASE] = sizeof(u32), + [XFRM_MSG_GETSADINFO - XFRM_MSG_BASE] = sizeof(u32), + [XFRM_MSG_NEWSPDINFO - XFRM_MSG_BASE] = sizeof(u32), + [XFRM_MSG_GETSPDINFO - XFRM_MSG_BASE] = sizeof(u32), + [XFRM_MSG_MAPPING - XFRM_MSG_BASE] = XMSGSIZE(xfrm_user_mapping) +}; + +static const struct nla_policy compat_policy[XFRMA_MAX+1] = { + [XFRMA_SA] = { .len = XMSGSIZE(compat_xfrm_usersa_info)}, + [XFRMA_POLICY] = { .len = XMSGSIZE(compat_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_user_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 }, + [XFRMA_MTIMER_THRESH] = { .type = NLA_U32 }, +}; + +static struct nlmsghdr *xfrm_nlmsg_put_compat(struct sk_buff *skb, + const struct nlmsghdr *nlh_src, u16 type) +{ + int payload = compat_msg_min[type]; + int src_len = xfrm_msg_min[type]; + struct nlmsghdr *nlh_dst; + + /* Compat messages are shorter or equal to native (+padding) */ + if (WARN_ON_ONCE(src_len < payload)) + return ERR_PTR(-EMSGSIZE); + + nlh_dst = nlmsg_put(skb, nlh_src->nlmsg_pid, nlh_src->nlmsg_seq, + nlh_src->nlmsg_type, payload, nlh_src->nlmsg_flags); + if (!nlh_dst) + return ERR_PTR(-EMSGSIZE); + + memset(nlmsg_data(nlh_dst), 0, payload); + + switch (nlh_src->nlmsg_type) { + /* Compat message has the same layout as native */ + case XFRM_MSG_DELSA: + case XFRM_MSG_DELPOLICY: + case XFRM_MSG_FLUSHSA: + case XFRM_MSG_FLUSHPOLICY: + case XFRM_MSG_NEWAE: + case XFRM_MSG_REPORT: + case XFRM_MSG_MIGRATE: + case XFRM_MSG_NEWSADINFO: + case XFRM_MSG_NEWSPDINFO: + case XFRM_MSG_MAPPING: + WARN_ON_ONCE(src_len != payload); + memcpy(nlmsg_data(nlh_dst), nlmsg_data(nlh_src), src_len); + break; + /* 4 byte alignment for trailing u64 on native, but not on compat */ + case XFRM_MSG_NEWSA: + case XFRM_MSG_NEWPOLICY: + case XFRM_MSG_UPDSA: + case XFRM_MSG_UPDPOLICY: + WARN_ON_ONCE(src_len != payload + 4); + memcpy(nlmsg_data(nlh_dst), nlmsg_data(nlh_src), payload); + break; + case XFRM_MSG_EXPIRE: { + const struct xfrm_user_expire *src_ue = nlmsg_data(nlh_src); + struct compat_xfrm_user_expire *dst_ue = nlmsg_data(nlh_dst); + + /* compat_xfrm_user_expire has 4-byte smaller state */ + memcpy(dst_ue, src_ue, sizeof(dst_ue->state)); + dst_ue->hard = src_ue->hard; + break; + } + case XFRM_MSG_ACQUIRE: { + const struct xfrm_user_acquire *src_ua = nlmsg_data(nlh_src); + struct compat_xfrm_user_acquire *dst_ua = nlmsg_data(nlh_dst); + + memcpy(dst_ua, src_ua, offsetof(struct compat_xfrm_user_acquire, aalgos)); + dst_ua->aalgos = src_ua->aalgos; + dst_ua->ealgos = src_ua->ealgos; + dst_ua->calgos = src_ua->calgos; + dst_ua->seq = src_ua->seq; + break; + } + case XFRM_MSG_POLEXPIRE: { + const struct xfrm_user_polexpire *src_upe = nlmsg_data(nlh_src); + struct compat_xfrm_user_polexpire *dst_upe = nlmsg_data(nlh_dst); + + /* compat_xfrm_user_polexpire has 4-byte smaller state */ + memcpy(dst_upe, src_upe, sizeof(dst_upe->pol)); + dst_upe->hard = src_upe->hard; + break; + } + case XFRM_MSG_ALLOCSPI: { + const struct xfrm_userspi_info *src_usi = nlmsg_data(nlh_src); + struct compat_xfrm_userspi_info *dst_usi = nlmsg_data(nlh_dst); + + /* compat_xfrm_user_polexpire has 4-byte smaller state */ + memcpy(dst_usi, src_usi, sizeof(src_usi->info)); + dst_usi->min = src_usi->min; + dst_usi->max = src_usi->max; + break; + } + /* Not being sent by kernel */ + case XFRM_MSG_GETSA: + case XFRM_MSG_GETPOLICY: + case XFRM_MSG_GETAE: + case XFRM_MSG_GETSADINFO: + case XFRM_MSG_GETSPDINFO: + default: + pr_warn_once("unsupported nlmsg_type %d\n", nlh_src->nlmsg_type); + return ERR_PTR(-EOPNOTSUPP); + } + + return nlh_dst; +} + +static int xfrm_nla_cpy(struct sk_buff *dst, const struct nlattr *src, int len) +{ + return nla_put(dst, src->nla_type, len, nla_data(src)); +} + +static int xfrm_xlate64_attr(struct sk_buff *dst, const struct nlattr *src) +{ + switch (src->nla_type) { + case XFRMA_PAD: + /* Ignore */ + return 0; + case XFRMA_UNSPEC: + case XFRMA_ALG_AUTH: + case XFRMA_ALG_CRYPT: + case XFRMA_ALG_COMP: + case XFRMA_ENCAP: + case XFRMA_TMPL: + return xfrm_nla_cpy(dst, src, nla_len(src)); + case XFRMA_SA: + return xfrm_nla_cpy(dst, src, XMSGSIZE(compat_xfrm_usersa_info)); + case XFRMA_POLICY: + return xfrm_nla_cpy(dst, src, XMSGSIZE(compat_xfrm_userpolicy_info)); + case XFRMA_SEC_CTX: + return xfrm_nla_cpy(dst, src, nla_len(src)); + case XFRMA_LTIME_VAL: + return nla_put_64bit(dst, src->nla_type, nla_len(src), + nla_data(src), XFRMA_PAD); + case XFRMA_REPLAY_VAL: + case XFRMA_REPLAY_THRESH: + case XFRMA_ETIMER_THRESH: + case XFRMA_SRCADDR: + case XFRMA_COADDR: + return xfrm_nla_cpy(dst, src, nla_len(src)); + case XFRMA_LASTUSED: + return nla_put_64bit(dst, src->nla_type, nla_len(src), + nla_data(src), XFRMA_PAD); + case XFRMA_POLICY_TYPE: + case XFRMA_MIGRATE: + case XFRMA_ALG_AEAD: + case XFRMA_KMADDRESS: + case XFRMA_ALG_AUTH_TRUNC: + case XFRMA_MARK: + case XFRMA_TFCPAD: + case XFRMA_REPLAY_ESN_VAL: + case XFRMA_SA_EXTRA_FLAGS: + case XFRMA_PROTO: + case XFRMA_ADDRESS_FILTER: + case XFRMA_OFFLOAD_DEV: + case XFRMA_SET_MARK: + case XFRMA_SET_MARK_MASK: + case XFRMA_IF_ID: + case XFRMA_MTIMER_THRESH: + return xfrm_nla_cpy(dst, src, nla_len(src)); + default: + BUILD_BUG_ON(XFRMA_MAX != XFRMA_MTIMER_THRESH); + pr_warn_once("unsupported nla_type %d\n", src->nla_type); + return -EOPNOTSUPP; + } +} + +/* Take kernel-built (64bit layout) and create 32bit layout for userspace */ +static int xfrm_xlate64(struct sk_buff *dst, const struct nlmsghdr *nlh_src) +{ + u16 type = nlh_src->nlmsg_type - XFRM_MSG_BASE; + const struct nlattr *nla, *attrs; + struct nlmsghdr *nlh_dst; + int len, remaining; + + nlh_dst = xfrm_nlmsg_put_compat(dst, nlh_src, type); + if (IS_ERR(nlh_dst)) + return PTR_ERR(nlh_dst); + + attrs = nlmsg_attrdata(nlh_src, xfrm_msg_min[type]); + len = nlmsg_attrlen(nlh_src, xfrm_msg_min[type]); + + nla_for_each_attr(nla, attrs, len, remaining) { + int err; + + switch (nlh_src->nlmsg_type) { + case XFRM_MSG_NEWSPDINFO: + err = xfrm_nla_cpy(dst, nla, nla_len(nla)); + break; + default: + err = xfrm_xlate64_attr(dst, nla); + break; + } + if (err) + return err; + } + + nlmsg_end(dst, nlh_dst); + + return 0; +} + +static int xfrm_alloc_compat(struct sk_buff *skb, const struct nlmsghdr *nlh_src) +{ + u16 type = nlh_src->nlmsg_type - XFRM_MSG_BASE; + struct sk_buff *new = NULL; + int err; + + if (type >= ARRAY_SIZE(xfrm_msg_min)) { + pr_warn_once("unsupported nlmsg_type %d\n", nlh_src->nlmsg_type); + return -EOPNOTSUPP; + } + + if (skb_shinfo(skb)->frag_list == NULL) { + new = alloc_skb(skb->len + skb_tailroom(skb), GFP_ATOMIC); + if (!new) + return -ENOMEM; + skb_shinfo(skb)->frag_list = new; + } + + err = xfrm_xlate64(skb_shinfo(skb)->frag_list, nlh_src); + if (err) { + if (new) { + kfree_skb(new); + skb_shinfo(skb)->frag_list = NULL; + } + return err; + } + + return 0; +} + +/* Calculates len of translated 64-bit message. */ +static size_t xfrm_user_rcv_calculate_len64(const struct nlmsghdr *src, + struct nlattr *attrs[XFRMA_MAX + 1], + int maxtype) +{ + size_t len = nlmsg_len(src); + + switch (src->nlmsg_type) { + case XFRM_MSG_NEWSA: + case XFRM_MSG_NEWPOLICY: + case XFRM_MSG_ALLOCSPI: + case XFRM_MSG_ACQUIRE: + case XFRM_MSG_UPDPOLICY: + case XFRM_MSG_UPDSA: + len += 4; + break; + case XFRM_MSG_EXPIRE: + case XFRM_MSG_POLEXPIRE: + len += 8; + break; + case XFRM_MSG_NEWSPDINFO: + /* attirbutes are xfrm_spdattr_type_t, not xfrm_attr_type_t */ + return len; + default: + break; + } + + /* Unexpected for anything, but XFRM_MSG_NEWSPDINFO, please + * correct both 64=>32-bit and 32=>64-bit translators to copy + * new attributes. + */ + if (WARN_ON_ONCE(maxtype)) + return len; + + if (attrs[XFRMA_SA]) + len += 4; + if (attrs[XFRMA_POLICY]) + len += 4; + + /* XXX: some attrs may need to be realigned + * if !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + */ + + return len; +} + +static int xfrm_attr_cpy32(void *dst, size_t *pos, const struct nlattr *src, + size_t size, int copy_len, int payload) +{ + struct nlmsghdr *nlmsg = dst; + struct nlattr *nla; + + /* xfrm_user_rcv_msg_compat() relies on fact that 32-bit messages + * have the same len or shorted than 64-bit ones. + * 32-bit translation that is bigger than 64-bit original is unexpected. + */ + if (WARN_ON_ONCE(copy_len > payload)) + copy_len = payload; + + if (size - *pos < nla_attr_size(payload)) + return -ENOBUFS; + + nla = dst + *pos; + + memcpy(nla, src, nla_attr_size(copy_len)); + nla->nla_len = nla_attr_size(payload); + *pos += nla_attr_size(copy_len); + nlmsg->nlmsg_len += nla->nla_len; + + memset(dst + *pos, 0, payload - copy_len); + *pos += payload - copy_len; + + return 0; +} + +static int xfrm_xlate32_attr(void *dst, const struct nlattr *nla, + size_t *pos, size_t size, + struct netlink_ext_ack *extack) +{ + int type = nla_type(nla); + u16 pol_len32, pol_len64; + int err; + + if (type > XFRMA_MAX) { + BUILD_BUG_ON(XFRMA_MAX != XFRMA_MTIMER_THRESH); + NL_SET_ERR_MSG(extack, "Bad attribute"); + return -EOPNOTSUPP; + } + type = array_index_nospec(type, XFRMA_MAX + 1); + if (nla_len(nla) < compat_policy[type].len) { + NL_SET_ERR_MSG(extack, "Attribute bad length"); + return -EOPNOTSUPP; + } + + pol_len32 = compat_policy[type].len; + pol_len64 = xfrma_policy[type].len; + + /* XFRMA_SA and XFRMA_POLICY - need to know how-to translate */ + if (pol_len32 != pol_len64) { + if (nla_len(nla) != compat_policy[type].len) { + NL_SET_ERR_MSG(extack, "Attribute bad length"); + return -EOPNOTSUPP; + } + err = xfrm_attr_cpy32(dst, pos, nla, size, pol_len32, pol_len64); + if (err) + return err; + } + + return xfrm_attr_cpy32(dst, pos, nla, size, nla_len(nla), nla_len(nla)); +} + +static int xfrm_xlate32(struct nlmsghdr *dst, const struct nlmsghdr *src, + struct nlattr *attrs[XFRMA_MAX+1], + size_t size, u8 type, int maxtype, + struct netlink_ext_ack *extack) +{ + size_t pos; + int i; + + memcpy(dst, src, NLMSG_HDRLEN); + dst->nlmsg_len = NLMSG_HDRLEN + xfrm_msg_min[type]; + memset(nlmsg_data(dst), 0, xfrm_msg_min[type]); + + switch (src->nlmsg_type) { + /* Compat message has the same layout as native */ + case XFRM_MSG_DELSA: + case XFRM_MSG_GETSA: + case XFRM_MSG_DELPOLICY: + case XFRM_MSG_GETPOLICY: + case XFRM_MSG_FLUSHSA: + case XFRM_MSG_FLUSHPOLICY: + case XFRM_MSG_NEWAE: + case XFRM_MSG_GETAE: + case XFRM_MSG_REPORT: + case XFRM_MSG_MIGRATE: + case XFRM_MSG_NEWSADINFO: + case XFRM_MSG_GETSADINFO: + case XFRM_MSG_NEWSPDINFO: + case XFRM_MSG_GETSPDINFO: + case XFRM_MSG_MAPPING: + memcpy(nlmsg_data(dst), nlmsg_data(src), compat_msg_min[type]); + break; + /* 4 byte alignment for trailing u64 on native, but not on compat */ + case XFRM_MSG_NEWSA: + case XFRM_MSG_NEWPOLICY: + case XFRM_MSG_UPDSA: + case XFRM_MSG_UPDPOLICY: + memcpy(nlmsg_data(dst), nlmsg_data(src), compat_msg_min[type]); + break; + case XFRM_MSG_EXPIRE: { + const struct compat_xfrm_user_expire *src_ue = nlmsg_data(src); + struct xfrm_user_expire *dst_ue = nlmsg_data(dst); + + /* compat_xfrm_user_expire has 4-byte smaller state */ + memcpy(dst_ue, src_ue, sizeof(src_ue->state)); + dst_ue->hard = src_ue->hard; + break; + } + case XFRM_MSG_ACQUIRE: { + const struct compat_xfrm_user_acquire *src_ua = nlmsg_data(src); + struct xfrm_user_acquire *dst_ua = nlmsg_data(dst); + + memcpy(dst_ua, src_ua, offsetof(struct compat_xfrm_user_acquire, aalgos)); + dst_ua->aalgos = src_ua->aalgos; + dst_ua->ealgos = src_ua->ealgos; + dst_ua->calgos = src_ua->calgos; + dst_ua->seq = src_ua->seq; + break; + } + case XFRM_MSG_POLEXPIRE: { + const struct compat_xfrm_user_polexpire *src_upe = nlmsg_data(src); + struct xfrm_user_polexpire *dst_upe = nlmsg_data(dst); + + /* compat_xfrm_user_polexpire has 4-byte smaller state */ + memcpy(dst_upe, src_upe, sizeof(src_upe->pol)); + dst_upe->hard = src_upe->hard; + break; + } + case XFRM_MSG_ALLOCSPI: { + const struct compat_xfrm_userspi_info *src_usi = nlmsg_data(src); + struct xfrm_userspi_info *dst_usi = nlmsg_data(dst); + + /* compat_xfrm_user_polexpire has 4-byte smaller state */ + memcpy(dst_usi, src_usi, sizeof(src_usi->info)); + dst_usi->min = src_usi->min; + dst_usi->max = src_usi->max; + break; + } + default: + NL_SET_ERR_MSG(extack, "Unsupported message type"); + return -EOPNOTSUPP; + } + pos = dst->nlmsg_len; + + if (maxtype) { + /* attirbutes are xfrm_spdattr_type_t, not xfrm_attr_type_t */ + WARN_ON_ONCE(src->nlmsg_type != XFRM_MSG_NEWSPDINFO); + + for (i = 1; i <= maxtype; i++) { + int err; + + if (!attrs[i]) + continue; + + /* just copy - no need for translation */ + err = xfrm_attr_cpy32(dst, &pos, attrs[i], size, + nla_len(attrs[i]), nla_len(attrs[i])); + if (err) + return err; + } + return 0; + } + + for (i = 1; i < XFRMA_MAX + 1; i++) { + int err; + + if (i == XFRMA_PAD) + continue; + + if (!attrs[i]) + continue; + + err = xfrm_xlate32_attr(dst, attrs[i], &pos, size, extack); + if (err) + return err; + } + + return 0; +} + +static struct nlmsghdr *xfrm_user_rcv_msg_compat(const struct nlmsghdr *h32, + int maxtype, const struct nla_policy *policy, + struct netlink_ext_ack *extack) +{ + /* netlink_rcv_skb() checks if a message has full (struct nlmsghdr) */ + u16 type = h32->nlmsg_type - XFRM_MSG_BASE; + struct nlattr *attrs[XFRMA_MAX+1]; + struct nlmsghdr *h64; + size_t len; + int err; + + BUILD_BUG_ON(ARRAY_SIZE(xfrm_msg_min) != ARRAY_SIZE(compat_msg_min)); + + if (type >= ARRAY_SIZE(xfrm_msg_min)) + return ERR_PTR(-EINVAL); + + /* Don't call parse: the message might have only nlmsg header */ + if ((h32->nlmsg_type == XFRM_MSG_GETSA || + h32->nlmsg_type == XFRM_MSG_GETPOLICY) && + (h32->nlmsg_flags & NLM_F_DUMP)) + return NULL; + + err = nlmsg_parse_deprecated(h32, compat_msg_min[type], attrs, + maxtype ? : XFRMA_MAX, policy ? : compat_policy, extack); + if (err < 0) + return ERR_PTR(err); + + len = xfrm_user_rcv_calculate_len64(h32, attrs, maxtype); + /* The message doesn't need translation */ + if (len == nlmsg_len(h32)) + return NULL; + + len += NLMSG_HDRLEN; + h64 = kvmalloc(len, GFP_KERNEL); + if (!h64) + return ERR_PTR(-ENOMEM); + + err = xfrm_xlate32(h64, h32, attrs, len, type, maxtype, extack); + if (err < 0) { + kvfree(h64); + return ERR_PTR(err); + } + + return h64; +} + +static int xfrm_user_policy_compat(u8 **pdata32, int optlen) +{ + struct compat_xfrm_userpolicy_info *p = (void *)*pdata32; + u8 *src_templates, *dst_templates; + u8 *data64; + + if (optlen < sizeof(*p)) + return -EINVAL; + + data64 = kmalloc_track_caller(optlen + 4, GFP_USER | __GFP_NOWARN); + if (!data64) + return -ENOMEM; + + memcpy(data64, *pdata32, sizeof(*p)); + memset(data64 + sizeof(*p), 0, 4); + + src_templates = *pdata32 + sizeof(*p); + dst_templates = data64 + sizeof(*p) + 4; + memcpy(dst_templates, src_templates, optlen - sizeof(*p)); + + kfree(*pdata32); + *pdata32 = data64; + return 0; +} + +static struct xfrm_translator xfrm_translator = { + .owner = THIS_MODULE, + .alloc_compat = xfrm_alloc_compat, + .rcv_msg_compat = xfrm_user_rcv_msg_compat, + .xlate_user_policy_sockptr = xfrm_user_policy_compat, +}; + +static int __init xfrm_compat_init(void) +{ + return xfrm_register_translator(&xfrm_translator); +} + +static void __exit xfrm_compat_exit(void) +{ + xfrm_unregister_translator(&xfrm_translator); +} + +module_init(xfrm_compat_init); +module_exit(xfrm_compat_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Dmitry Safonov"); +MODULE_DESCRIPTION("XFRM 32-bit compatibility layer"); |