From c2d305e51038167dd9de8d476c72f667d84cad8b Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 29 Mar 2019 21:16:24 +0100 Subject: xfrm: remove input indirection from xfrm_mode No need for any indirection or abstraction here, both functions are pretty much the same and quite small, they also have no external dependencies. xfrm_prepare_input can then be made static. With allmodconfig build, size increase of vmlinux is 25 byte: Before: text data bss dec filename 15730207 6936924 4046908 26714039 vmlinux After: 15730208 6936948 4046908 26714064 vmlinux v2: Fix INET_XFRM_MODE_TRANSPORT name in is-enabled test (Sabrina Dubroca) change copied comment to refer to transport and network header, not skb->{h,nh}, which don't exist anymore. (Sabrina) make xfrm_prepare_input static (Eyal Birger) Signed-off-by: Florian Westphal Reviewed-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_input.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 72 insertions(+), 3 deletions(-) (limited to 'net/xfrm') diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c index ea5ac053c15d..0edf3fb73585 100644 --- a/net/xfrm/xfrm_input.c +++ b/net/xfrm/xfrm_input.c @@ -166,7 +166,7 @@ int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq) } EXPORT_SYMBOL(xfrm_parse_spi); -int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) +static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) { struct xfrm_mode *inner_mode = x->inner_mode; int err; @@ -184,7 +184,76 @@ int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) skb->protocol = inner_mode->afinfo->eth_proto; return inner_mode->input2(x, skb); } -EXPORT_SYMBOL(xfrm_prepare_input); + +/* Remove encapsulation header. + * + * The IP header will be moved over the top of the encapsulation header. + * + * On entry, skb_transport_header() shall point to where the IP header + * should be and skb_network_header() shall be set to where the IP header + * currently is. skb->data shall point to the start of the payload. + */ +static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb) +{ +#if IS_ENABLED(CONFIG_INET_XFRM_MODE_TRANSPORT) + int ihl = skb->data - skb_transport_header(skb); + + if (skb->transport_header != skb->network_header) { + memmove(skb_transport_header(skb), + skb_network_header(skb), ihl); + skb->network_header = skb->transport_header; + } + ip_hdr(skb)->tot_len = htons(skb->len + ihl); + skb_reset_transport_header(skb); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + +static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb) +{ +#if IS_ENABLED(CONFIG_INET6_XFRM_MODE_TRANSPORT) + int ihl = skb->data - skb_transport_header(skb); + + if (skb->transport_header != skb->network_header) { + memmove(skb_transport_header(skb), + skb_network_header(skb), ihl); + skb->network_header = skb->transport_header; + } + ipv6_hdr(skb)->payload_len = htons(skb->len + ihl - + sizeof(struct ipv6hdr)); + skb_reset_transport_header(skb); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + +static int xfrm_inner_mode_input(struct xfrm_state *x, + const struct xfrm_mode *inner_mode, + struct sk_buff *skb) +{ + switch (inner_mode->encap) { + case XFRM_MODE_BEET: + case XFRM_MODE_TUNNEL: + return xfrm_prepare_input(x, skb); + case XFRM_MODE_TRANSPORT: + if (inner_mode->family == AF_INET) + return xfrm4_transport_input(x, skb); + if (inner_mode->family == AF_INET6) + return xfrm6_transport_input(x, skb); + break; + case XFRM_MODE_ROUTEOPTIMIZATION: + WARN_ON_ONCE(1); + break; + default: + WARN_ON_ONCE(1); + break; + } + + return -EOPNOTSUPP; +} int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { @@ -410,7 +479,7 @@ resume: } } - if (inner_mode->input(x, skb)) { + if (xfrm_inner_mode_input(x, inner_mode, skb)) { XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); goto drop; } -- cgit v1.2.3-59-g8ed1b