From 0a69452cb45add0841c2bc1e75c25f6bd4f1d8d9 Mon Sep 17 00:00:00 2001 From: Diego Beltrami Date: Tue, 3 Oct 2006 23:47:05 -0700 Subject: [XFRM]: BEET mode This patch introduces the BEET mode (Bound End-to-End Tunnel) with as specified by the ietf draft at the following link: http://www.ietf.org/internet-drafts/draft-nikander-esp-beet-mode-06.txt The patch provides only single family support (i.e. inner family = outer family). Signed-off-by: Diego Beltrami Signed-off-by: Miika Komu Signed-off-by: Herbert Xu Signed-off-by: Abhinav Pathak Signed-off-by: Jeff Ahrenholz Signed-off-by: David S. Miller --- net/ipv4/Kconfig | 9 +++ net/ipv4/Makefile | 1 + net/ipv4/esp4.c | 26 ++++++--- net/ipv4/ipcomp.c | 5 +- net/ipv4/xfrm4_mode_beet.c | 139 +++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 172 insertions(+), 8 deletions(-) create mode 100644 net/ipv4/xfrm4_mode_beet.c (limited to 'net/ipv4') diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig index d172a980444..5572071af73 100644 --- a/net/ipv4/Kconfig +++ b/net/ipv4/Kconfig @@ -434,6 +434,15 @@ config INET_XFRM_MODE_TUNNEL If unsure, say Y. +config INET_XFRM_MODE_BEET + tristate "IP: IPsec BEET mode" + default y + select XFRM + ---help--- + Support for IPsec BEET mode. + + If unsure, say Y. + config INET_DIAG tristate "INET: socket monitoring interface" default y diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile index f66049e28ae..15645c51520 100644 --- a/net/ipv4/Makefile +++ b/net/ipv4/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_INET_AH) += ah4.o obj-$(CONFIG_INET_ESP) += esp4.o obj-$(CONFIG_INET_IPCOMP) += ipcomp.o obj-$(CONFIG_INET_XFRM_TUNNEL) += xfrm4_tunnel.o +obj-$(CONFIG_INET_XFRM_MODE_BEET) += xfrm4_mode_beet.o obj-$(CONFIG_INET_TUNNEL) += tunnel4.o obj-$(CONFIG_INET_XFRM_MODE_TRANSPORT) += xfrm4_mode_transport.o obj-$(CONFIG_INET_XFRM_MODE_TUNNEL) += xfrm4_mode_tunnel.o diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 13b29360d10..b5c205b5766 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -253,7 +253,8 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) * as per draft-ietf-ipsec-udp-encaps-06, * section 3.1.2 */ - if (x->props.mode == XFRM_MODE_TRANSPORT) + if (x->props.mode == XFRM_MODE_TRANSPORT || + x->props.mode == XFRM_MODE_BEET) skb->ip_summed = CHECKSUM_UNNECESSARY; } @@ -271,17 +272,28 @@ static u32 esp4_get_max_size(struct xfrm_state *x, int mtu) { struct esp_data *esp = x->data; u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4); - - if (x->props.mode == XFRM_MODE_TUNNEL) { - mtu = ALIGN(mtu + 2, blksize); - } else { - /* The worst case. */ + int enclen = 0; + + switch (x->props.mode) { + case XFRM_MODE_TUNNEL: + mtu = ALIGN(mtu +2, blksize); + break; + default: + case XFRM_MODE_TRANSPORT: + /* The worst case */ mtu = ALIGN(mtu + 2, 4) + blksize - 4; + break; + case XFRM_MODE_BEET: + /* The worst case. */ + enclen = IPV4_BEET_PHMAXLEN; + mtu = ALIGN(mtu + enclen + 2, blksize); + break; } + if (esp->conf.padlen) mtu = ALIGN(mtu, esp->conf.padlen); - return mtu + x->props.header_len + esp->auth.icv_trunc_len; + return mtu + x->props.header_len + esp->auth.icv_trunc_len - enclen; } static void esp4_err(struct sk_buff *skb, u32 info) diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c index 2017d36024d..3839b706142 100644 --- a/net/ipv4/ipcomp.c +++ b/net/ipv4/ipcomp.c @@ -206,6 +206,7 @@ static void ipcomp4_err(struct sk_buff *skb, u32 info) static struct xfrm_state *ipcomp_tunnel_create(struct xfrm_state *x) { struct xfrm_state *t; + u8 mode = XFRM_MODE_TUNNEL; t = xfrm_state_alloc(); if (t == NULL) @@ -216,7 +217,9 @@ static struct xfrm_state *ipcomp_tunnel_create(struct xfrm_state *x) t->id.daddr.a4 = x->id.daddr.a4; memcpy(&t->sel, &x->sel, sizeof(t->sel)); t->props.family = AF_INET; - t->props.mode = XFRM_MODE_TUNNEL; + if (x->props.mode == XFRM_MODE_BEET) + mode = x->props.mode; + t->props.mode = mode; t->props.saddr.a4 = x->props.saddr.a4; t->props.flags = x->props.flags; diff --git a/net/ipv4/xfrm4_mode_beet.c b/net/ipv4/xfrm4_mode_beet.c new file mode 100644 index 00000000000..89cf59ea7bb --- /dev/null +++ b/net/ipv4/xfrm4_mode_beet.c @@ -0,0 +1,139 @@ +/* + * xfrm4_mode_beet.c - BEET mode encapsulation for IPv4. + * + * Copyright (c) 2006 Diego Beltrami + * Miika Komu + * Herbert Xu + * Abhinav Pathak + * Jeff Ahrenholz + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/* Add encapsulation header. + * + * The top IP header will be constructed per draft-nikander-esp-beet-mode-06.txt. + * The following fields in it shall be filled in by x->type->output: + * tot_len + * check + * + * On exit, skb->h will be set to the start of the payload to be processed + * by x->type->output and skb->nh will be set to the top IP header. + */ +static int xfrm4_beet_output(struct xfrm_state *x, struct sk_buff *skb) +{ + struct iphdr *iph, *top_iph = NULL; + int hdrlen, optlen; + + iph = skb->nh.iph; + skb->h.ipiph = iph; + + hdrlen = 0; + optlen = iph->ihl * 4 - sizeof(*iph); + if (unlikely(optlen)) + hdrlen += IPV4_BEET_PHMAXLEN - (optlen & 4); + + skb->nh.raw = skb_push(skb, x->props.header_len + hdrlen); + top_iph = skb->nh.iph; + hdrlen = iph->ihl * 4 - optlen; + skb->h.raw += hdrlen; + + memmove(top_iph, iph, hdrlen); + if (unlikely(optlen)) { + struct ip_beet_phdr *ph; + + BUG_ON(optlen < 0); + + ph = (struct ip_beet_phdr *)skb->h.raw; + ph->padlen = 4 - (optlen & 4); + ph->hdrlen = (optlen + ph->padlen + sizeof(*ph)) / 8; + ph->nexthdr = top_iph->protocol; + + top_iph->protocol = IPPROTO_BEETPH; + top_iph->ihl = sizeof(struct iphdr) / 4; + } + + top_iph->saddr = x->props.saddr.a4; + top_iph->daddr = x->id.daddr.a4; + + return 0; +} + +static int xfrm4_beet_input(struct xfrm_state *x, struct sk_buff *skb) +{ + struct iphdr *iph = skb->nh.iph; + int phlen = 0; + int optlen = 0; + __u8 ph_nexthdr = 0, protocol = 0; + int err = -EINVAL; + + protocol = iph->protocol; + + if (unlikely(iph->protocol == IPPROTO_BEETPH)) { + struct ip_beet_phdr *ph = (struct ip_beet_phdr*)(iph + 1); + + if (!pskb_may_pull(skb, sizeof(*ph))) + goto out; + + phlen = ph->hdrlen * 8; + optlen = phlen - ph->padlen - sizeof(*ph); + if (optlen < 0 || optlen & 3 || optlen > 250) + goto out; + + if (!pskb_may_pull(skb, phlen)) + goto out; + + ph_nexthdr = ph->nexthdr; + } + + skb_push(skb, sizeof(*iph) - phlen + optlen); + memmove(skb->data, skb->nh.raw, sizeof(*iph)); + skb->nh.raw = skb->data; + + iph = skb->nh.iph; + iph->ihl = (sizeof(*iph) + optlen) / 4; + iph->tot_len = htons(skb->len); + iph->daddr = x->sel.daddr.a4; + iph->saddr = x->sel.saddr.a4; + if (ph_nexthdr) + iph->protocol = ph_nexthdr; + else + iph->protocol = protocol; + iph->check = 0; + iph->check = ip_fast_csum(skb->nh.raw, iph->ihl); + err = 0; +out: + return err; +} + +static struct xfrm_mode xfrm4_beet_mode = { + .input = xfrm4_beet_input, + .output = xfrm4_beet_output, + .owner = THIS_MODULE, + .encap = XFRM_MODE_BEET, +}; + +static int __init xfrm4_beet_init(void) +{ + return xfrm_register_mode(&xfrm4_beet_mode, AF_INET); +} + +static void __exit xfrm4_beet_exit(void) +{ + int err; + + err = xfrm_unregister_mode(&xfrm4_beet_mode, AF_INET); + BUG_ON(err); +} + +module_init(xfrm4_beet_init); +module_exit(xfrm4_beet_exit); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_XFRM_MODE(AF_INET, XFRM_MODE_BEET); -- cgit v1.2.3