From patchwork Sat Apr 18 14:52:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sabrina Dubroca X-Patchwork-Id: 221048 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNWANTED_LANGUAGE_BODY, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F34DDC38A29 for ; Sat, 18 Apr 2020 14:53:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7B06206D6 for ; Sat, 18 Apr 2020 14:53:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728841AbgDROxd convert rfc822-to-8bit (ORCPT ); Sat, 18 Apr 2020 10:53:33 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:36940 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726720AbgDROxa (ORCPT ); Sat, 18 Apr 2020 10:53:30 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-409-wGqbWrdCN56cc0WRf9ifiA-1; Sat, 18 Apr 2020 10:53:24 -0400 X-MC-Unique: wGqbWrdCN56cc0WRf9ifiA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E14848018A6; Sat, 18 Apr 2020 14:53:23 +0000 (UTC) Received: from hog.localdomain, (unknown [10.40.192.14]) by smtp.corp.redhat.com (Postfix) with ESMTP id 723BF5C1C3; Sat, 18 Apr 2020 14:53:22 +0000 (UTC) From: Sabrina Dubroca To: netdev@vger.kernel.org Cc: Steffen Klassert , Sabrina Dubroca Subject: [PATCH ipsec-next 1/2] xfrm: add support for UDPv6 encapsulation of ESP Date: Sat, 18 Apr 2020 16:52:55 +0200 Message-Id: <171a0c14575013cbd634fbb634b82eaa6423a994.1587219054.git.sd@queasysnail.net> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: queasysnail.net Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch adds support for encapsulation of ESP over UDPv6. The code is very similar to the IPv4 encapsulation implementation, and allows to easily add espintcp on IPv6 as a follow-up. Signed-off-by: Sabrina Dubroca --- include/net/ipv6_stubs.h | 3 + include/net/xfrm.h | 5 + net/ipv4/udp.c | 10 +- net/ipv6/af_inet6.c | 4 + net/ipv6/ah6.c | 1 + net/ipv6/esp6.c | 225 +++++++++++++++++++++++++++++++++----- net/ipv6/esp6_offload.c | 7 +- net/ipv6/ip6_vti.c | 18 ++- net/ipv6/ipcomp6.c | 1 + net/ipv6/xfrm6_input.c | 106 +++++++++++++++++- net/ipv6/xfrm6_protocol.c | 48 ++++++++ net/xfrm/xfrm_interface.c | 3 + 12 files changed, 394 insertions(+), 37 deletions(-) diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h index 3e7d2c0e79ca..f033a17b53b6 100644 --- a/include/net/ipv6_stubs.h +++ b/include/net/ipv6_stubs.h @@ -56,6 +56,9 @@ struct ipv6_stub { void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr, const struct in6_addr *solicited_addr, bool router, bool solicited, bool override, bool inc_opt); +#if IS_ENABLED(CONFIG_XFRM) + int (*xfrm6_udp_encap_rcv)(struct sock *sk, struct sk_buff *skb); +#endif struct neigh_table *nd_tbl; }; extern const struct ipv6_stub *ipv6_stub __read_mostly; diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 8f71c111e65a..2577666c34c8 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1406,6 +1406,8 @@ struct xfrm4_protocol { struct xfrm6_protocol { int (*handler)(struct sk_buff *skb); + int (*input_handler)(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type); int (*cb_handler)(struct sk_buff *skb, int err); int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info); @@ -1590,6 +1592,8 @@ int xfrm6_extract_header(struct sk_buff *skb); int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb); int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi, struct ip6_tnl *t); +int xfrm6_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type); int xfrm6_transport_finish(struct sk_buff *skb, int async); int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t); int xfrm6_rcv(struct sk_buff *skb); @@ -1610,6 +1614,7 @@ int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb, #ifdef CONFIG_XFRM int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb); +int xfrm6_udp_encap_rcv(struct sock *sk, struct sk_buff *skb); int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen); #else diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index db76b9609299..23732210aade 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -112,6 +112,9 @@ #include #include #include +#if IS_ENABLED(CONFIG_IPV6) +#include +#endif struct udp_table udp_table __read_mostly; EXPORT_SYMBOL(udp_table); @@ -2555,7 +2558,12 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname, #ifdef CONFIG_XFRM case UDP_ENCAP_ESPINUDP: case UDP_ENCAP_ESPINUDP_NON_IKE: - up->encap_rcv = xfrm4_udp_encap_rcv; +#if IS_ENABLED(CONFIG_IPV6) + if (sk->sk_family == AF_INET6) + up->encap_rcv = ipv6_stub->xfrm6_udp_encap_rcv; + else +#endif + up->encap_rcv = xfrm4_udp_encap_rcv; #endif /* FALLTHROUGH */ case UDP_ENCAP_L2TPINUDP: diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index d727c3b41495..65a34c3fa209 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -59,6 +59,7 @@ #endif #include #include +#include #include #include @@ -960,6 +961,9 @@ static const struct ipv6_stub ipv6_stub_impl = { .ip6_del_rt = ip6_del_rt, .udpv6_encap_enable = udpv6_encap_enable, .ndisc_send_na = ndisc_send_na, +#if IS_ENABLED(CONFIG_XFRM) + .xfrm6_udp_encap_rcv = xfrm6_udp_encap_rcv, +#endif .nd_tbl = &nd_tbl, }; diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c index 95835e8d99aa..fc186ff4efd1 100644 --- a/net/ipv6/ah6.c +++ b/net/ipv6/ah6.c @@ -767,6 +767,7 @@ static const struct xfrm_type ah6_type = { static struct xfrm6_protocol ah6_protocol = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = ah6_rcv_cb, .err_handler = ah6_err, .priority = 0, diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c index 11143d039f16..baab0fc35e59 100644 --- a/net/ipv6/esp6.c +++ b/net/ipv6/esp6.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -39,6 +40,11 @@ struct esp_skb_cb { void *tmp; }; +struct esp_output_extra { + __be32 seqhi; + u32 esphoff; +}; + #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) /* @@ -72,9 +78,9 @@ static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) return kmalloc(len, GFP_ATOMIC); } -static inline __be32 *esp_tmp_seqhi(void *tmp) +static inline void *esp_tmp_extra(void *tmp) { - return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); + return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra)); } static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) @@ -104,16 +110,17 @@ static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, static void esp_ssg_unref(struct xfrm_state *x, void *tmp) { + struct esp_output_extra *extra = esp_tmp_extra(tmp); struct crypto_aead *aead = x->data; - int seqhilen = 0; + int extralen = 0; u8 *iv; struct aead_request *req; struct scatterlist *sg; if (x->props.flags & XFRM_STATE_ESN) - seqhilen += sizeof(__be32); + extralen += sizeof(*extra); - iv = esp_tmp_iv(aead, tmp, seqhilen); + iv = esp_tmp_iv(aead, tmp, extralen); req = esp_tmp_req(aead, iv); /* Unref skb_frag_pages in the src scatterlist if necessary. @@ -124,6 +131,23 @@ static void esp_ssg_unref(struct xfrm_state *x, void *tmp) put_page(sg_page(sg)); } +static void esp_output_encap_csum(struct sk_buff *skb) +{ + /* UDP encap with IPv6 requires a valid checksum */ + if (*skb_mac_header(skb) == IPPROTO_UDP) { + struct udphdr *uh = udp_hdr(skb); + struct ipv6hdr *ip6h = ipv6_hdr(skb); + int len = ntohs(uh->len); + unsigned int offset = skb_transport_offset(skb); + __wsum csum = skb_checksum(skb, offset, skb->len - offset, 0); + + uh->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, + len, IPPROTO_UDP, csum); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + } +} + static void esp_output_done(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; @@ -143,6 +167,8 @@ static void esp_output_done(struct crypto_async_request *base, int err) esp_ssg_unref(x, tmp); kfree(tmp); + esp_output_encap_csum(skb); + if (xo && (xo->flags & XFRM_DEV_RESUME)) { if (err) { XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); @@ -163,7 +189,7 @@ static void esp_restore_header(struct sk_buff *skb, unsigned int offset) { struct ip_esp_hdr *esph = (void *)(skb->data + offset); void *tmp = ESP_SKB_CB(skb)->tmp; - __be32 *seqhi = esp_tmp_seqhi(tmp); + __be32 *seqhi = esp_tmp_extra(tmp); esph->seq_no = esph->spi; esph->spi = *seqhi; @@ -171,27 +197,36 @@ static void esp_restore_header(struct sk_buff *skb, unsigned int offset) static void esp_output_restore_header(struct sk_buff *skb) { - esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); + void *tmp = ESP_SKB_CB(skb)->tmp; + struct esp_output_extra *extra = esp_tmp_extra(tmp); + + esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff - + sizeof(__be32)); } static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, struct xfrm_state *x, struct ip_esp_hdr *esph, - __be32 *seqhi) + struct esp_output_extra *extra) { /* For ESN we move the header forward by 4 bytes to * accomodate the high bits. We will move it back after * encryption. */ if ((x->props.flags & XFRM_STATE_ESN)) { + __u32 seqhi; struct xfrm_offload *xo = xfrm_offload(skb); - esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); - *seqhi = esph->spi; if (xo) - esph->seq_no = htonl(xo->seq.hi); + seqhi = xo->seq.hi; else - esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); + seqhi = XFRM_SKB_CB(skb)->seq.output.hi; + + extra->esphoff = (unsigned char *)esph - + skb_transport_header(skb); + esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4); + extra->seqhi = esph->spi; + esph->seq_no = htonl(seqhi); } esph->spi = x->id.spi; @@ -207,15 +242,84 @@ static void esp_output_done_esn(struct crypto_async_request *base, int err) esp_output_done(base, err); } +static struct ip_esp_hdr *esp6_output_udp_encap(struct sk_buff *skb, + int encap_type, + struct esp_info *esp, + __be16 sport, + __be16 dport) +{ + struct udphdr *uh; + __be32 *udpdata32; + unsigned int len; + + len = skb->len + esp->tailen - skb_transport_offset(skb); + if (len > U16_MAX) + return ERR_PTR(-EMSGSIZE); + + uh = (struct udphdr *)esp->esph; + uh->source = sport; + uh->dest = dport; + uh->len = htons(len); + uh->check = 0; + + *skb_mac_header(skb) = IPPROTO_UDP; + + if (encap_type == UDP_ENCAP_ESPINUDP_NON_IKE) { + udpdata32 = (__be32 *)(uh + 1); + udpdata32[0] = udpdata32[1] = 0; + return (struct ip_esp_hdr *)(udpdata32 + 2); + } + + return (struct ip_esp_hdr *)(uh + 1); +} + +static int esp6_output_encap(struct xfrm_state *x, struct sk_buff *skb, + struct esp_info *esp) +{ + struct xfrm_encap_tmpl *encap = x->encap; + struct ip_esp_hdr *esph; + __be16 sport, dport; + int encap_type; + + spin_lock_bh(&x->lock); + sport = encap->encap_sport; + dport = encap->encap_dport; + encap_type = encap->encap_type; + spin_unlock_bh(&x->lock); + + switch (encap_type) { + default: + case UDP_ENCAP_ESPINUDP: + case UDP_ENCAP_ESPINUDP_NON_IKE: + esph = esp6_output_udp_encap(skb, encap_type, esp, sport, dport); + break; + } + + if (IS_ERR(esph)) + return PTR_ERR(esph); + + esp->esph = esph; + + return 0; +} + int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { u8 *tail; u8 *vaddr; int nfrags; + int esph_offset; struct page *page; struct sk_buff *trailer; int tailen = esp->tailen; + if (x->encap) { + int err = esp6_output_encap(x, skb, esp); + + if (err < 0) + return err; + } + if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { nfrags = 1; @@ -274,10 +378,13 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info } cow: + esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb); + nfrags = skb_cow_data(skb, tailen, &trailer); if (nfrags < 0) goto out; tail = skb_tail_pointer(trailer); + esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset); skip_cow: esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); @@ -295,20 +402,20 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info void *tmp; int ivlen; int assoclen; - int seqhilen; - __be32 *seqhi; + int extralen; struct page *page; struct ip_esp_hdr *esph; struct aead_request *req; struct crypto_aead *aead; struct scatterlist *sg, *dsg; + struct esp_output_extra *extra; int err = -ENOMEM; assoclen = sizeof(struct ip_esp_hdr); - seqhilen = 0; + extralen = 0; if (x->props.flags & XFRM_STATE_ESN) { - seqhilen += sizeof(__be32); + extralen += sizeof(*extra); assoclen += sizeof(__be32); } @@ -316,12 +423,12 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info alen = crypto_aead_authsize(aead); ivlen = crypto_aead_ivsize(aead); - tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); + tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen); if (!tmp) goto error; - seqhi = esp_tmp_seqhi(tmp); - iv = esp_tmp_iv(aead, tmp, seqhilen); + extra = esp_tmp_extra(tmp); + iv = esp_tmp_iv(aead, tmp, extralen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); @@ -330,7 +437,8 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info else dsg = &sg[esp->nfrags]; - esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); + esph = esp_output_set_esn(skb, x, esp->esph, extra); + esp->esph = esph; sg_init_table(sg, esp->nfrags); err = skb_to_sgvec(skb, sg, @@ -394,6 +502,7 @@ int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info case 0: if ((x->props.flags & XFRM_STATE_ESN)) esp_output_restore_header(skb); + esp_output_encap_csum(skb); } if (sg != dsg) @@ -438,11 +547,13 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) esp.plen = esp.clen - skb->len - esp.tfclen; esp.tailen = esp.tfclen + esp.plen + alen; + esp.esph = ip_esp_hdr(skb); + esp.nfrags = esp6_output_head(x, skb, &esp); if (esp.nfrags < 0) return esp.nfrags; - esph = ip_esp_hdr(skb); + esph = esp.esph; esph->spi = x->id.spi; esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); @@ -517,6 +628,56 @@ int esp6_input_done2(struct sk_buff *skb, int err) if (unlikely(err < 0)) goto out; + if (x->encap) { + const struct ipv6hdr *ip6h = ipv6_hdr(skb); + struct xfrm_encap_tmpl *encap = x->encap; + struct udphdr *uh = (void *)(skb_network_header(skb) + hdr_len); + __be16 source; + + switch (x->encap->encap_type) { + case UDP_ENCAP_ESPINUDP: + case UDP_ENCAP_ESPINUDP_NON_IKE: + source = uh->source; + break; + default: + WARN_ON_ONCE(1); + err = -EINVAL; + goto out; + } + + /* + * 1) if the NAT-T peer's IP or port changed then + * advertize the change to the keying daemon. + * This is an inbound SA, so just compare + * SRC ports. + */ + if (!ipv6_addr_equal(&ip6h->saddr, &x->props.saddr.in6) || + source != encap->encap_sport) { + xfrm_address_t ipaddr; + + memcpy(&ipaddr.a6, &ip6h->saddr.s6_addr, sizeof(ipaddr.a6)); + km_new_mapping(x, &ipaddr, source); + + /* XXX: perhaps add an extra + * policy check here, to see + * if we should allow or + * reject a packet from a + * different source + * address/port. + */ + } + + /* + * 2) ignore UDP/TCP checksums in case + * of NAT-T in Transport Mode, or + * perform other post-processing fixes + * as per draft-ietf-ipsec-udp-encaps-06, + * section 3.1.2 + */ + if (x->props.mode == XFRM_MODE_TRANSPORT) + skb->ip_summed = CHECKSUM_UNNECESSARY; + } + skb_postpull_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); skb_pull_rcsum(skb, hlen); @@ -632,7 +793,7 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) goto out; ESP_SKB_CB(skb)->tmp = tmp; - seqhi = esp_tmp_seqhi(tmp); + seqhi = esp_tmp_extra(tmp); iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); @@ -836,9 +997,6 @@ static int esp6_init_state(struct xfrm_state *x) u32 align; int err; - if (x->encap) - return -EINVAL; - x->data = NULL; if (x->aead) @@ -867,6 +1025,22 @@ static int esp6_init_state(struct xfrm_state *x) break; } + if (x->encap) { + struct xfrm_encap_tmpl *encap = x->encap; + + switch (encap->encap_type) { + default: + err = -EINVAL; + goto error; + case UDP_ENCAP_ESPINUDP: + x->props.header_len += sizeof(struct udphdr); + break; + case UDP_ENCAP_ESPINUDP_NON_IKE: + x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); + break; + } + } + align = ALIGN(crypto_aead_blocksize(aead), 4); x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); @@ -893,6 +1067,7 @@ static const struct xfrm_type esp6_type = { static struct xfrm6_protocol esp6_protocol = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = esp6_rcv_cb, .err_handler = esp6_err, .priority = 0, diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c index fd535053245b..40b15fbcc2cb 100644 --- a/net/ipv6/esp6_offload.c +++ b/net/ipv6/esp6_offload.c @@ -235,7 +235,6 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features int alen; int blksize; struct xfrm_offload *xo; - struct ip_esp_hdr *esph; struct crypto_aead *aead; struct esp_info esp; bool hw_offload = true; @@ -276,13 +275,13 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features seq = xo->seq.low; - esph = ip_esp_hdr(skb); - esph->spi = x->id.spi; + esp.esph = ip_esp_hdr(skb); + esp.esph->spi = x->id.spi; skb_push(skb, -skb_network_offset(skb)); if (xo->flags & XFRM_GSO_SEGMENT) { - esph->seq_no = htonl(seq); + esp.esph->seq_no = htonl(seq); if (!skb_is_gso(skb)) xo->seq.low++; diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index 524006aa0d78..ffa6f792cdf6 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -296,7 +296,8 @@ static void vti6_dev_uninit(struct net_device *dev) dev_put(dev); } -static int vti6_rcv(struct sk_buff *skb) +static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type) { struct ip6_tnl *t; const struct ipv6hdr *ipv6h = ipv6_hdr(skb); @@ -323,7 +324,10 @@ static int vti6_rcv(struct sk_buff *skb) rcu_read_unlock(); - return xfrm6_rcv_tnl(skb, t); + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; + XFRM_SPI_SKB_CB(skb)->family = AF_INET6; + XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); + return xfrm_input(skb, nexthdr, spi, encap_type); } rcu_read_unlock(); return -EINVAL; @@ -332,6 +336,13 @@ static int vti6_rcv(struct sk_buff *skb) return 0; } +static int vti6_rcv(struct sk_buff *skb) +{ + int nexthdr = skb_network_header(skb)[IP6CB(skb)->nhoff]; + + return vti6_input_proto(skb, nexthdr, 0, 0); +} + static int vti6_rcv_cb(struct sk_buff *skb, int err) { unsigned short family; @@ -1167,6 +1178,7 @@ static struct pernet_operations vti6_net_ops = { static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { .handler = vti6_rcv, + .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, @@ -1174,6 +1186,7 @@ static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { .handler = vti6_rcv, + .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, @@ -1181,6 +1194,7 @@ static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { .handler = vti6_rcv, + .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c index 3752bd3e92ce..99668bfebd85 100644 --- a/net/ipv6/ipcomp6.c +++ b/net/ipv6/ipcomp6.c @@ -183,6 +183,7 @@ static const struct xfrm_type ipcomp6_type = { static struct xfrm6_protocol ipcomp6_protocol = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = ipcomp6_rcv_cb, .err_handler = ipcomp6_err, .priority = 0, diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c index a52cb3fc6df5..56f52353b324 100644 --- a/net/ipv6/xfrm6_input.c +++ b/net/ipv6/xfrm6_input.c @@ -35,9 +35,12 @@ EXPORT_SYMBOL(xfrm6_rcv_spi); static int xfrm6_transport_finish2(struct net *net, struct sock *sk, struct sk_buff *skb) { - if (xfrm_trans_queue(skb, ip6_rcv_finish)) - __kfree_skb(skb); - return -1; + if (xfrm_trans_queue(skb, ip6_rcv_finish)) { + kfree_skb(skb); + return NET_RX_DROP; + } + + return 0; } int xfrm6_transport_finish(struct sk_buff *skb, int async) @@ -60,13 +63,106 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async) if (xo && (xo->flags & XFRM_GRO)) { skb_mac_header_rebuild(skb); skb_reset_transport_header(skb); - return -1; + return 0; } NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, dev_net(skb->dev), NULL, skb, skb->dev, NULL, xfrm6_transport_finish2); - return -1; + return 0; +} + +/* If it's a keepalive packet, then just eat it. + * If it's an encapsulated packet, then pass it to the + * IPsec xfrm input. + * Returns 0 if skb passed to xfrm or was dropped. + * Returns >0 if skb should be passed to UDP. + * Returns <0 if skb should be resubmitted (-ret is protocol) + */ +int xfrm6_udp_encap_rcv(struct sock *sk, struct sk_buff *skb) +{ + struct udp_sock *up = udp_sk(sk); + struct udphdr *uh; + struct ipv6hdr *ip6h; + int len; + int ip6hlen = sizeof(struct ipv6hdr); + + __u8 *udpdata; + __be32 *udpdata32; + __u16 encap_type = up->encap_type; + + /* if this is not encapsulated socket, then just return now */ + if (!encap_type) + return 1; + + /* If this is a paged skb, make sure we pull up + * whatever data we need to look at. */ + len = skb->len - sizeof(struct udphdr); + if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8))) + return 1; + + /* Now we can get the pointers */ + uh = udp_hdr(skb); + udpdata = (__u8 *)uh + sizeof(struct udphdr); + udpdata32 = (__be32 *)udpdata; + + switch (encap_type) { + default: + case UDP_ENCAP_ESPINUDP: + /* Check if this is a keepalive packet. If so, eat it. */ + if (len == 1 && udpdata[0] == 0xff) { + goto drop; + } else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) { + /* ESP Packet without Non-ESP header */ + len = sizeof(struct udphdr); + } else + /* Must be an IKE packet.. pass it through */ + return 1; + break; + case UDP_ENCAP_ESPINUDP_NON_IKE: + /* Check if this is a keepalive packet. If so, eat it. */ + if (len == 1 && udpdata[0] == 0xff) { + goto drop; + } else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) && + udpdata32[0] == 0 && udpdata32[1] == 0) { + + /* ESP Packet with Non-IKE marker */ + len = sizeof(struct udphdr) + 2 * sizeof(u32); + } else + /* Must be an IKE packet.. pass it through */ + return 1; + break; + } + + /* At this point we are sure that this is an ESPinUDP packet, + * so we need to remove 'len' bytes from the packet (the UDP + * header and optional ESP marker bytes) and then modify the + * protocol to ESP, and then call into the transform receiver. + */ + if (skb_unclone(skb, GFP_ATOMIC)) + goto drop; + + /* Now we can update and verify the packet length... */ + ip6h = ipv6_hdr(skb); + ip6h->payload_len = htons(ntohs(ip6h->payload_len) - len); + if (skb->len < ip6hlen + len) { + /* packet is too small!?! */ + goto drop; + } + + /* pull the data buffer up to the ESP header and set the + * transport header to point to ESP. Keep UDP on the stack + * for later. + */ + __skb_pull(skb, len); + skb_reset_transport_header(skb); + + /* process ESP */ + return xfrm6_rcv_encap(skb, IPPROTO_ESP, 0, encap_type); + +drop: + kfree_skb(skb); + return 0; } int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t) diff --git a/net/ipv6/xfrm6_protocol.c b/net/ipv6/xfrm6_protocol.c index 34cb65c7d5a7..ea2f805d3b01 100644 --- a/net/ipv6/xfrm6_protocol.c +++ b/net/ipv6/xfrm6_protocol.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -58,6 +59,53 @@ static int xfrm6_rcv_cb(struct sk_buff *skb, u8 protocol, int err) return 0; } +int xfrm6_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type) +{ + int ret; + struct xfrm6_protocol *handler; + struct xfrm6_protocol __rcu **head = proto_handlers(nexthdr); + + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; + XFRM_SPI_SKB_CB(skb)->family = AF_INET6; + XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); + + if (!head) + goto out; + + if (!skb_dst(skb)) { + const struct ipv6hdr *ip6h = ipv6_hdr(skb); + int flags = RT6_LOOKUP_F_HAS_SADDR; + struct dst_entry *dst; + struct flowi6 fl6 = { + .flowi6_iif = skb->dev->ifindex, + .daddr = ip6h->daddr, + .saddr = ip6h->saddr, + .flowlabel = ip6_flowinfo(ip6h), + .flowi6_mark = skb->mark, + .flowi6_proto = ip6h->nexthdr, + }; + + dst = ip6_route_input_lookup(dev_net(skb->dev), skb->dev, &fl6, + skb, flags); + if (dst->error) + goto drop; + skb_dst_set(skb, dst); + } + + for_each_protocol_rcu(*head, handler) + if ((ret = handler->input_handler(skb, nexthdr, spi, encap_type)) != -EINVAL) + return ret; + +out: + icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); + +drop: + kfree_skb(skb); + return 0; +} +EXPORT_SYMBOL(xfrm6_rcv_encap); + static int xfrm6_esp_rcv(struct sk_buff *skb) { int ret; diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c index 3361e3ac5714..ce045cadd00b 100644 --- a/net/xfrm/xfrm_interface.c +++ b/net/xfrm/xfrm_interface.c @@ -757,6 +757,7 @@ static struct pernet_operations xfrmi_net_ops = { static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = xfrmi_rcv_cb, .err_handler = xfrmi6_err, .priority = 10, @@ -764,6 +765,7 @@ static struct xfrm6_protocol xfrmi_esp6_protocol __read_mostly = { static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = xfrmi_rcv_cb, .err_handler = xfrmi6_err, .priority = 10, @@ -771,6 +773,7 @@ static struct xfrm6_protocol xfrmi_ah6_protocol __read_mostly = { static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = { .handler = xfrm6_rcv, + .input_handler = xfrm_input, .cb_handler = xfrmi_rcv_cb, .err_handler = xfrmi6_err, .priority = 10,