diff options
author | 2020-09-21 15:36:55 +0100 | |
---|---|---|
committer | 2020-09-24 08:53:03 +0200 | |
commit | 5106f4a8acff480e244300bc5097c0ad7048c3a2 (patch) | |
tree | 0f5319f64a61020eb78646b75ccdc6b52d424fe3 /net | |
parent | netlink/compat: Append NLMSG_DONE/extack to frag_list (diff) | |
download | linux-5106f4a8acff.tar.gz linux-5106f4a8acff.tar.bz2 linux-5106f4a8acff.zip |
xfrm/compat: Add 32=>64-bit messages translator
Provide the user-to-kernel translator under XFRM_USER_COMPAT, that
creates for 32-bit xfrm-user message a 64-bit translation.
The translation is afterwards reused by xfrm_user code just as if
userspace had sent 64-bit message.
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/xfrm/Kconfig | 3 | ||||
-rw-r--r-- | net/xfrm/xfrm_compat.c | 274 | ||||
-rw-r--r-- | net/xfrm/xfrm_user.c | 57 |
3 files changed, 315 insertions, 19 deletions
diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig index e79b48dab61b..3adf31a83a79 100644 --- a/net/xfrm/Kconfig +++ b/net/xfrm/Kconfig @@ -30,7 +30,8 @@ config XFRM_USER config XFRM_USER_COMPAT tristate "Compatible ABI support" - depends on XFRM_USER && COMPAT_FOR_U64_ALIGNMENT + depends on XFRM_USER && COMPAT_FOR_U64_ALIGNMENT && \ + HAVE_EFFICIENT_UNALIGNED_ACCESS select WANT_COMPAT_NETLINK_MESSAGES help Transformation(XFRM) user configuration interface like IPsec diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c index aece41b44ff2..b1b5f972538d 100644 --- a/net/xfrm/xfrm_compat.c +++ b/net/xfrm/xfrm_compat.c @@ -96,6 +96,39 @@ static const int compat_msg_min[XFRM_NR_MSGTYPES] = { [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_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 struct nlmsghdr *xfrm_nlmsg_put_compat(struct sk_buff *skb, const struct nlmsghdr *nlh_src, u16 type) { @@ -303,9 +336,250 @@ static int xfrm_alloc_compat(struct sk_buff *skb, const struct nlmsghdr *nlh_src 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]) +{ + 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; + default: + break; + } + + 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; + + 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(payload); + 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_IF_ID); + NL_SET_ERR_MSG(extack, "Bad attribute"); + return -EOPNOTSUPP; + } + 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, 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; + + 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); + /* The message doesn't need translation */ + if (len == nlmsg_len(h32)) + return NULL; + + len += NLMSG_HDRLEN; + h64 = kvmalloc(len, GFP_KERNEL | __GFP_ZERO); + if (!h64) + return ERR_PTR(-ENOMEM); + + err = xfrm_xlate32(h64, h32, attrs, len, type, extack); + if (err < 0) { + kvfree(h64); + return ERR_PTR(err); + } + + return h64; +} + static struct xfrm_translator xfrm_translator = { .owner = THIS_MODULE, .alloc_compat = xfrm_alloc_compat, + .rcv_msg_compat = xfrm_user_rcv_msg_compat, }; static int __init xfrm_compat_init(void) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 7fd7b16a8805..d0c32a8fcc4a 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1019,7 +1019,6 @@ static int xfrm_dump_sa_done(struct netlink_callback *cb) 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); @@ -2610,7 +2609,7 @@ EXPORT_SYMBOL_GPL(xfrm_msg_min); #undef XMSGSIZE -static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = { +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}, @@ -2642,6 +2641,7 @@ static const struct nla_policy xfrma_policy[XFRMA_MAX+1] = { [XFRMA_SET_MARK_MASK] = { .type = NLA_U32 }, [XFRMA_IF_ID] = { .type = NLA_U32 }, }; +EXPORT_SYMBOL_GPL(xfrma_policy); static const struct nla_policy xfrma_spd_policy[XFRMA_SPD_MAX+1] = { [XFRMA_SPD_IPV4_HTHRESH] = { .len = sizeof(struct xfrmu_spdhthresh) }, @@ -2691,11 +2691,9 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, struct net *net = sock_net(skb->sk); struct nlattr *attrs[XFRMA_MAX+1]; const struct xfrm_link *link; + struct nlmsghdr *nlh64 = NULL; int type, err; - if (in_compat_syscall()) - return -EOPNOTSUPP; - type = nlh->nlmsg_type; if (type > XFRM_MSG_MAX) return -EINVAL; @@ -2707,32 +2705,55 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, if (!netlink_net_capable(skb, CAP_NET_ADMIN)) return -EPERM; + if (in_compat_syscall()) { + struct xfrm_translator *xtr = xfrm_get_translator(); + + if (!xtr) + return -EOPNOTSUPP; + + nlh64 = xtr->rcv_msg_compat(nlh, link->nla_max, + link->nla_pol, extack); + xfrm_put_translator(xtr); + if (IS_ERR(nlh64)) + return PTR_ERR(nlh64); + if (nlh64) + nlh = nlh64; + } + 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, + }; - { - struct netlink_dump_control c = { - .start = link->start, - .dump = link->dump, - .done = link->done, - }; - return netlink_dump_start(net->xfrm.nlsk, skb, nlh, &c); + if (link->dump == NULL) { + err = -EINVAL; + goto err; } + + err = netlink_dump_start(net->xfrm.nlsk, skb, nlh, &c); + goto err; } 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; + goto err; - if (link->doit == NULL) - return -EINVAL; + if (link->doit == NULL) { + err = -EINVAL; + goto err; + } + + err = link->doit(skb, nlh, attrs); - return link->doit(skb, nlh, attrs); +err: + kvfree(nlh64); + return err; } static void xfrm_netlink_rcv(struct sk_buff *skb) |