From 1de70830066b72b6a8e259e5363f6c0bc4ba7bbc Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 29 Mar 2019 21:16:29 +0100 Subject: xfrm: remove output2 indirection from xfrm_mode similar to previous patch: no external module dependencies, so we can avoid the indirection by placing this in the core. This change removes the last indirection from xfrm_mode and the xfrm4|6_mode_{beet,tunnel}.c modules contain (almost) no code anymore. Before: text data bss dec hex filename 3957 136 0 4093 ffd net/xfrm/xfrm_output.o 587 44 0 631 277 net/ipv4/xfrm4_mode_beet.o 649 32 0 681 2a9 net/ipv4/xfrm4_mode_tunnel.o 625 44 0 669 29d net/ipv6/xfrm6_mode_beet.o 599 32 0 631 277 net/ipv6/xfrm6_mode_tunnel.o After: text data bss dec hex filename 5359 184 0 5543 15a7 net/xfrm/xfrm_output.o 171 24 0 195 c3 net/ipv4/xfrm4_mode_beet.o 171 24 0 195 c3 net/ipv4/xfrm4_mode_tunnel.o 172 24 0 196 c4 net/ipv6/xfrm6_mode_beet.o 172 24 0 196 c4 net/ipv6/xfrm6_mode_tunnel.o v2: fold the *encap_add functions into xfrm*_prepare_output preserve (move) output2 comment (Sabrina) use x->outer_mode->encap, not inner fix a build breakage on ppc (kbuild robot) Signed-off-by: Florian Westphal Reviewed-by: Sabrina Dubroca Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_output.c | 212 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 207 insertions(+), 5 deletions(-) (limited to 'net/xfrm') diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c index 05926dcf5d17..9bdf16f13606 100644 --- a/net/xfrm/xfrm_output.c +++ b/net/xfrm/xfrm_output.c @@ -17,8 +17,11 @@ #include #include #include +#include #include +#include "xfrm_inout.h" + static int xfrm_output2(struct net *net, struct sock *sk, struct sk_buff *skb); static int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb); @@ -141,6 +144,190 @@ static int xfrm6_ro_output(struct xfrm_state *x, struct sk_buff *skb) #endif } +/* Add encapsulation header. + * + * The top IP header will be constructed per draft-nikander-esp-beet-mode-06.txt. + */ +static int xfrm4_beet_encap_add(struct xfrm_state *x, struct sk_buff *skb) +{ + struct ip_beet_phdr *ph; + struct iphdr *top_iph; + int hdrlen, optlen; + + hdrlen = 0; + optlen = XFRM_MODE_SKB_CB(skb)->optlen; + if (unlikely(optlen)) + hdrlen += IPV4_BEET_PHMAXLEN - (optlen & 4); + + skb_set_network_header(skb, -x->props.header_len - hdrlen + + (XFRM_MODE_SKB_CB(skb)->ihl - sizeof(*top_iph))); + if (x->sel.family != AF_INET6) + skb->network_header += IPV4_BEET_PHMAXLEN; + skb->mac_header = skb->network_header + + offsetof(struct iphdr, protocol); + skb->transport_header = skb->network_header + sizeof(*top_iph); + + xfrm4_beet_make_header(skb); + + ph = __skb_pull(skb, XFRM_MODE_SKB_CB(skb)->ihl - hdrlen); + + top_iph = ip_hdr(skb); + + if (unlikely(optlen)) { + if (WARN_ON(optlen < 0)) + return -EINVAL; + + ph->padlen = 4 - (optlen & 4); + ph->hdrlen = optlen / 8; + ph->nexthdr = top_iph->protocol; + if (ph->padlen) + memset(ph + 1, IPOPT_NOP, ph->padlen); + + 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; +} + +/* Add encapsulation header. + * + * The top IP header will be constructed per RFC 2401. + */ +static int xfrm4_tunnel_encap_add(struct xfrm_state *x, struct sk_buff *skb) +{ + struct dst_entry *dst = skb_dst(skb); + struct iphdr *top_iph; + int flags; + + skb_set_inner_network_header(skb, skb_network_offset(skb)); + skb_set_inner_transport_header(skb, skb_transport_offset(skb)); + + skb_set_network_header(skb, -x->props.header_len); + skb->mac_header = skb->network_header + + offsetof(struct iphdr, protocol); + skb->transport_header = skb->network_header + sizeof(*top_iph); + top_iph = ip_hdr(skb); + + top_iph->ihl = 5; + top_iph->version = 4; + + top_iph->protocol = xfrm_af2proto(skb_dst(skb)->ops->family); + + /* DS disclosing depends on XFRM_SA_XFLAG_DONT_ENCAP_DSCP */ + if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP) + top_iph->tos = 0; + else + top_iph->tos = XFRM_MODE_SKB_CB(skb)->tos; + top_iph->tos = INET_ECN_encapsulate(top_iph->tos, + XFRM_MODE_SKB_CB(skb)->tos); + + flags = x->props.flags; + if (flags & XFRM_STATE_NOECN) + IP_ECN_clear(top_iph); + + top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) ? + 0 : (XFRM_MODE_SKB_CB(skb)->frag_off & htons(IP_DF)); + + top_iph->ttl = ip4_dst_hoplimit(xfrm_dst_child(dst)); + + top_iph->saddr = x->props.saddr.a4; + top_iph->daddr = x->id.daddr.a4; + ip_select_ident(dev_net(dst->dev), skb, NULL); + + return 0; +} + +#if IS_ENABLED(CONFIG_IPV6) +static int xfrm6_tunnel_encap_add(struct xfrm_state *x, struct sk_buff *skb) +{ + struct dst_entry *dst = skb_dst(skb); + struct ipv6hdr *top_iph; + int dsfield; + + skb_set_inner_network_header(skb, skb_network_offset(skb)); + skb_set_inner_transport_header(skb, skb_transport_offset(skb)); + + skb_set_network_header(skb, -x->props.header_len); + skb->mac_header = skb->network_header + + offsetof(struct ipv6hdr, nexthdr); + skb->transport_header = skb->network_header + sizeof(*top_iph); + top_iph = ipv6_hdr(skb); + + top_iph->version = 6; + + memcpy(top_iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl, + sizeof(top_iph->flow_lbl)); + top_iph->nexthdr = xfrm_af2proto(skb_dst(skb)->ops->family); + + if (x->props.extra_flags & XFRM_SA_XFLAG_DONT_ENCAP_DSCP) + dsfield = 0; + else + dsfield = XFRM_MODE_SKB_CB(skb)->tos; + dsfield = INET_ECN_encapsulate(dsfield, XFRM_MODE_SKB_CB(skb)->tos); + if (x->props.flags & XFRM_STATE_NOECN) + dsfield &= ~INET_ECN_MASK; + ipv6_change_dsfield(top_iph, 0, dsfield); + top_iph->hop_limit = ip6_dst_hoplimit(xfrm_dst_child(dst)); + top_iph->saddr = *(struct in6_addr *)&x->props.saddr; + top_iph->daddr = *(struct in6_addr *)&x->id.daddr; + return 0; +} + +static int xfrm6_beet_encap_add(struct xfrm_state *x, struct sk_buff *skb) +{ + struct ipv6hdr *top_iph; + struct ip_beet_phdr *ph; + int optlen, hdr_len; + + hdr_len = 0; + optlen = XFRM_MODE_SKB_CB(skb)->optlen; + if (unlikely(optlen)) + hdr_len += IPV4_BEET_PHMAXLEN - (optlen & 4); + + skb_set_network_header(skb, -x->props.header_len - hdr_len); + if (x->sel.family != AF_INET6) + skb->network_header += IPV4_BEET_PHMAXLEN; + skb->mac_header = skb->network_header + + offsetof(struct ipv6hdr, nexthdr); + skb->transport_header = skb->network_header + sizeof(*top_iph); + ph = __skb_pull(skb, XFRM_MODE_SKB_CB(skb)->ihl - hdr_len); + + xfrm6_beet_make_header(skb); + + top_iph = ipv6_hdr(skb); + if (unlikely(optlen)) { + if (WARN_ON(optlen < 0)) + return -EINVAL; + + ph->padlen = 4 - (optlen & 4); + ph->hdrlen = optlen / 8; + ph->nexthdr = top_iph->nexthdr; + if (ph->padlen) + memset(ph + 1, IPOPT_NOP, ph->padlen); + + top_iph->nexthdr = IPPROTO_BEETPH; + } + + top_iph->saddr = *(struct in6_addr *)&x->props.saddr; + top_iph->daddr = *(struct in6_addr *)&x->id.daddr; + return 0; +} +#endif + +/* Add encapsulation header. + * + * On exit, the transport header will be set to the start of the + * encapsulation header to be filled in by x->type->output and the mac + * header will be set to the nextheader (protocol for IPv4) field of the + * extension header directly preceding the encapsulation header, or in + * its absence, that of the top IP header. + * The value of the network header will always point to the top IP header + * while skb->data will point to the payload. + */ static int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb) { int err; @@ -152,7 +339,15 @@ static int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb) IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE; skb->protocol = htons(ETH_P_IP); - return x->outer_mode->output2(x, skb); + switch (x->outer_mode->encap) { + case XFRM_MODE_BEET: + return xfrm4_beet_encap_add(x, skb); + case XFRM_MODE_TUNNEL: + return xfrm4_tunnel_encap_add(x, skb); + } + + WARN_ON_ONCE(1); + return -EOPNOTSUPP; } static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb) @@ -167,11 +362,18 @@ static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb) skb->ignore_df = 1; skb->protocol = htons(ETH_P_IPV6); - return x->outer_mode->output2(x, skb); -#else - WARN_ON_ONCE(1); - return -EOPNOTSUPP; + switch (x->outer_mode->encap) { + case XFRM_MODE_BEET: + return xfrm6_beet_encap_add(x, skb); + case XFRM_MODE_TUNNEL: + return xfrm6_tunnel_encap_add(x, skb); + default: + WARN_ON_ONCE(1); + return -EOPNOTSUPP; + } #endif + WARN_ON_ONCE(1); + return -EAFNOSUPPORT; } static int xfrm_outer_mode_output(struct xfrm_state *x, struct sk_buff *skb) -- cgit v1.2.3