From 115df3e38ed2389e43e9418d2fa8d3e79e920d40 Mon Sep 17 00:00:00 2001
From: Emmanuel Hocdet <manu@gandi.net>
Date: Mon, 5 Feb 2018 16:23:23 +0100
Subject: [PATCH] MINOR: accept-proxy: support proxy protocol v2 CRC32c
 checksum

When proxy protocol v2 CRC32c tlv is received, check it before accept
connection (as describe in "doc/proxy-protocol.txt").
---
 src/connection.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/connection.c b/src/connection.c
index db5134e6e..1ea96ae3d 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -613,6 +613,14 @@ int conn_recv_proxy(struct connection *conn, int flag)
 				tlv_offset += tlv_len + TLV_HEADER_SIZE;
 
 				switch (tlv_packet->type) {
+				case PP2_TYPE_CRC32C: {
+					void *tlv_crc32c_p = (void *)tlv_packet->value;
+					uint32_t n_crc32c = ntohl(read_u32(tlv_crc32c_p));
+					write_u32(tlv_crc32c_p, 0);
+					if (hash_crc32c(trash.str, PP2_HEADER_LEN + ntohs(hdr_v2->len)) != n_crc32c)
+						goto bad_header;
+					break;
+				}
 #ifdef CONFIG_HAP_NS
 				case PP2_TYPE_NETNS: {
 					const struct netns_entry *ns;