diff mbox series

[net-next,v4,10/13] flow_dissector: Parse GUE in UDP

Message ID 20240823201557.1794985-11-tom@herbertland.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series flow_dissector: Dissect UDP encapsulation protocols | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 2 maintainers not CCed: pabeni@redhat.com ast@fiberby.net
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 17 this patch: 17
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 72 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 3 this patch: 3
netdev/source_inline success Was 0 now: 0

Commit Message

Tom Herbert Aug. 23, 2024, 8:15 p.m. UTC 
Parse both version 0 and 1 of GUE encapsulated in UDP. Add helper
function __skb_direct_ip_dissect to convert an IP header to
IPPROTO_IPIP or IPPROTO_IPV6 (by looking just at the version
number)

Signed-off-by: Tom Herbert <tom@herbertland.com>
---
 net/core/flow_dissector.c | 60 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)
diff mbox series

Patch

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 1deb9c3a75aa..b59a9e896a31 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -821,6 +821,61 @@  __skb_flow_dissect_geneve(const struct sk_buff *skb,
 	return FLOW_DISSECT_RET_PROTO_AGAIN;
 }
 
+static __u8
+__skb_direct_ip_dissect(void *hdr)
+{
+	/* Direct encapsulation of IPv4 or IPv6 */
+
+	switch (((struct iphdr *)hdr)->version) {
+	case 4:
+		return IPPROTO_IPIP;
+	case 6:
+		return IPPROTO_IPV6;
+	default:
+		return 0;
+	}
+}
+
+static enum flow_dissect_ret
+__skb_flow_dissect_gue(const struct sk_buff *skb,
+		       struct flow_dissector *flow_dissector,
+		       void *target_container, const void *data,
+		       __u8 *p_ip_proto, int *p_nhoff,
+		       int hlen, unsigned int flags)
+{
+	struct guehdr *hdr, _hdr;
+	__u8 proto;
+
+	hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
+				   &_hdr);
+	if (!hdr)
+		return FLOW_DISSECT_RET_OUT_BAD;
+
+	switch (hdr->version) {
+	case 0:
+		if (unlikely(hdr->control))
+			return FLOW_DISSECT_RET_OUT_GOOD;
+
+		*p_nhoff += sizeof(struct guehdr) + (hdr->hlen << 2);
+		*p_ip_proto = hdr->proto_ctype;
+
+		break;
+	case 1:
+		/* Direct encapsulation of IPv4 or IPv6 */
+
+		proto = __skb_direct_ip_dissect(hdr);
+		if (proto) {
+			*p_ip_proto = proto;
+			break;
+		}
+		fallthrough;
+	default:
+		return FLOW_DISSECT_RET_OUT_GOOD;
+	}
+
+	return FLOW_DISSECT_RET_IPPROTO_AGAIN;
+}
+
 /**
  * __skb_flow_dissect_batadv() - dissect batman-adv header
  * @skb: sk_buff to with the batman-adv header
@@ -1002,6 +1057,11 @@  __skb_flow_dissect_udp(const struct sk_buff *skb, const struct net *net,
 		*p_ip_proto = fou_protocol;
 		ret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
 		break;
+	case UDP_ENCAP_GUE:
+		ret = __skb_flow_dissect_gue(skb, flow_dissector,
+					     target_container, data,
+					     p_ip_proto, p_nhoff, hlen, flags);
+		break;
 	case UDP_ENCAP_SCTP:
 		*p_ip_proto = IPPROTO_SCTP;
 		ret = FLOW_DISSECT_RET_IPPROTO_AGAIN;