From 37b9e7eb55659b270f0e8aebd98308716d935586 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 11 Jun 2021 12:50:11 +0200 Subject: xfrm: ipv6: move mip6_destopt_offset into xfrm core This helper is relatively small, just move this to the xfrm core and call it directly. Next patch does the same for the ROUTING type. Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_output.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) (limited to 'net/xfrm') diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c index 6b44b6e738f7..29959054a535 100644 --- a/net/xfrm/xfrm_output.c +++ b/net/xfrm/xfrm_output.c @@ -77,8 +77,65 @@ static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb) return 0; } +#if IS_ENABLED(CONFIG_IPV6_MIP6) +static int mip6_destopt_offset(struct xfrm_state *x, struct sk_buff *skb, + u8 **nexthdr) +{ + u16 offset = sizeof(struct ipv6hdr); + struct ipv6_opt_hdr *exthdr = + (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); + const unsigned char *nh = skb_network_header(skb); + unsigned int packet_len = skb_tail_pointer(skb) - + skb_network_header(skb); + int found_rhdr = 0; + + *nexthdr = &ipv6_hdr(skb)->nexthdr; + + while (offset + 1 <= packet_len) { + switch (**nexthdr) { + case NEXTHDR_HOP: + break; + case NEXTHDR_ROUTING: + found_rhdr = 1; + break; + case NEXTHDR_DEST: + /* HAO MUST NOT appear more than once. + * XXX: It is better to try to find by the end of + * XXX: packet if HAO exists. + */ + if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) { + net_dbg_ratelimited("mip6: hao exists already, override\n"); + return offset; + } + + if (found_rhdr) + return offset; + + break; + default: + return offset; + } + + offset += ipv6_optlen(exthdr); + *nexthdr = &exthdr->nexthdr; + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + } + + return offset; +} +#endif + static int xfrm6_hdr_offset(struct xfrm_state *x, struct sk_buff *skb, u8 **prevhdr) { + switch (x->type->proto) { +#if IS_ENABLED(CONFIG_IPV6_MIP6) + case IPPROTO_DSTOPTS: + return mip6_destopt_offset(x, skb, prevhdr); +#endif + default: + break; + } + return x->type->hdr_offset(x, skb, prevhdr); } -- cgit v1.2.3