icmp46_header_t *icmp;
ip_csum_t csum;
int rv;
+ ip6_address_t old_src, old_dst;
ip6 = vlib_buffer_get_current (p);
ip6_pay_len = clib_net_to_host_u16 (ip6->payload_length);
else if (inner_protocol == IP_PROTOCOL_ICMP6)
{
icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4;
- csum = inner_icmp->checksum;
- csum = ip_csum_sub_even (csum, *((u16 *) inner_icmp));
//It cannot be of a different type as ip6_icmp_to_icmp6_in_place succeeded
inner_icmp->type = (inner_icmp->type == ICMP6_echo_request) ?
ICMP4_echo_request : ICMP4_echo_reply;
- csum = ip_csum_add_even (csum, *((u16 *) inner_icmp));
- inner_icmp->checksum = ip_csum_fold (csum);
inner_protocol = IP_PROTOCOL_ICMP; //Will be copied to ip6 later
inner_L4_checksum = &inner_icmp->checksum;
}
return -1;
}
- csum = *inner_L4_checksum;
- csum = ip_csum_sub_even (csum, inner_ip6->src_address.as_u64[0]);
- csum = ip_csum_sub_even (csum, inner_ip6->src_address.as_u64[1]);
- csum = ip_csum_sub_even (csum, inner_ip6->dst_address.as_u64[0]);
- csum = ip_csum_sub_even (csum, inner_ip6->dst_address.as_u64[1]);
+ old_src.as_u64[0] = inner_ip6->src_address.as_u64[0];
+ old_src.as_u64[1] = inner_ip6->src_address.as_u64[1];
+ old_dst.as_u64[0] = inner_ip6->dst_address.as_u64[0];
+ old_dst.as_u64[1] = inner_ip6->dst_address.as_u64[1];
if ((rv = inner_fn (inner_ip6, inner_ip4, inner_ctx)) != 0)
return rv;
if (inner_ip4->protocol == IP_PROTOCOL_ICMP)
{
- //Remove remainings of the pseudo-header in the csum
- csum =
- ip_csum_sub_even (csum, clib_host_to_net_u16 (IP_PROTOCOL_ICMP6));
+ //Recompute ICMP checksum
+ icmp46_header_t *inner_icmp = (icmp46_header_t *) inner_l4;
+ inner_icmp->checksum = 0;
csum =
- ip_csum_sub_even (csum, inner_ip4->length - sizeof (*inner_ip4));
+ ip_incremental_checksum (0, inner_icmp,
+ clib_net_to_host_u16 (inner_ip4->length)
+ - sizeof (*inner_ip4));
+ inner_icmp->checksum = ~ip_csum_fold (csum);
}
else
{
//Update to new pseudo-header
+ csum = *inner_L4_checksum;
+ csum = ip_csum_sub_even (csum, old_src.as_u64[0]);
+ csum = ip_csum_sub_even (csum, old_src.as_u64[1]);
+ csum = ip_csum_sub_even (csum, old_dst.as_u64[0]);
+ csum = ip_csum_sub_even (csum, old_dst.as_u64[1]);
csum = ip_csum_add_even (csum, inner_ip4->src_address.as_u32);
csum = ip_csum_add_even (csum, inner_ip4->dst_address.as_u32);
+ *inner_L4_checksum = ip_csum_fold (csum);
}
- *inner_L4_checksum = ip_csum_fold (csum);
//Move up icmp header
ip4 = (ip4_header_t *) u8_ptr_add (inner_l4, -2 * sizeof (*ip4) - 8);
- clib_memcpy (u8_ptr_add (inner_l4, -sizeof (*ip4) - 8), icmp, 8);
+ clib_memcpy_fast (u8_ptr_add (inner_l4, -sizeof (*ip4) - 8), icmp, 8);
icmp = (icmp46_header_t *) u8_ptr_add (inner_l4, -sizeof (*ip4) - 8);
}
else
{
ip6_header_t *ip6;
u16 *checksum;
- ip_csum_t csum;
+ ip_csum_t csum = 0;
ip4_header_t *ip4;
u16 fragment_id;
u16 flags;
u8 l4_protocol;
u16 l4_offset;
int rv;
+ ip6_address_t old_src, old_dst;
ip6 = vlib_buffer_get_current (p);
{
udp_header_t *udp = ip6_next_header (ip6);
checksum = &udp->checksum;
- //UDP checksum is optional over IPv4
- if (!udp_checksum)
- goto no_csum;
}
- csum = ip_csum_sub_even (*checksum, ip6->src_address.as_u64[0]);
- csum = ip_csum_sub_even (csum, ip6->src_address.as_u64[1]);
- csum = ip_csum_sub_even (csum, ip6->dst_address.as_u64[0]);
- csum = ip_csum_sub_even (csum, ip6->dst_address.as_u64[1]);
+ old_src.as_u64[0] = ip6->src_address.as_u64[0];
+ old_src.as_u64[1] = ip6->src_address.as_u64[1];
+ old_dst.as_u64[0] = ip6->dst_address.as_u64[0];
+ old_dst.as_u64[1] = ip6->dst_address.as_u64[1];
-no_csum:
ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4));
vlib_buffer_advance (p, l4_offset - sizeof (*ip4));
}
else
{
+ csum = ip_csum_sub_even (*checksum, old_src.as_u64[0]);
+ csum = ip_csum_sub_even (csum, old_src.as_u64[1]);
+ csum = ip_csum_sub_even (csum, old_dst.as_u64[0]);
+ csum = ip_csum_sub_even (csum, old_dst.as_u64[1]);
csum = ip_csum_add_even (csum, ip4->dst_address.as_u32);
csum = ip_csum_add_even (csum, ip4->src_address.as_u32);
*checksum = ip_csum_fold (csum);
return 0;
}
+/**
+ * @brief Translate IPv6 packet to IPv4 (IP header only).
+ *
+ * @param p Buffer to translate.
+ * @param fn The function to translate header.
+ * @param ctx A context passed in the header translate function.
+ *
+ * @returns 0 on success, non-zero value otherwise.
+ */
+always_inline int
+ip6_to_ip4 (vlib_buffer_t * p, ip6_to_ip4_set_fn_t fn, void *ctx)
+{
+ ip6_header_t *ip6;
+ ip4_header_t *ip4;
+ u16 fragment_id;
+ u16 flags;
+ u16 frag_offset;
+ u8 l4_protocol;
+ u16 l4_offset;
+ int rv;
+
+ ip6 = vlib_buffer_get_current (p);
+
+ if (ip6_parse
+ (ip6, p->current_length, &l4_protocol, &l4_offset, &frag_offset))
+ return -1;
+
+ ip4 = (ip4_header_t *) u8_ptr_add (ip6, l4_offset - sizeof (*ip4));
+
+ vlib_buffer_advance (p, l4_offset - sizeof (*ip4));
+
+ if (PREDICT_FALSE (frag_offset))
+ {
+ //Only the first fragment
+ ip6_frag_hdr_t *hdr = (ip6_frag_hdr_t *) u8_ptr_add (ip6, frag_offset);
+ fragment_id = frag_id_6to4 (hdr->identification);
+ flags = clib_host_to_net_u16 (IP4_HEADER_FLAG_MORE_FRAGMENTS);
+ }
+ else
+ {
+ fragment_id = 0;
+ flags = 0;
+ }
+
+ if ((rv = fn (ip6, ip4, ctx)) != 0)
+ return rv;
+
+ ip4->ip_version_and_header_length =
+ IP4_VERSION_AND_HEADER_LENGTH_NO_OPTIONS;
+ ip4->tos = ip6_translate_tos (ip6);
+ ip4->length = u16_net_add (ip6->payload_length,
+ sizeof (*ip4) + sizeof (*ip6) - l4_offset);
+ ip4->fragment_id = fragment_id;
+ ip4->flags_and_fragment_offset = flags;
+ ip4->ttl = ip6->hop_limit;
+ ip4->protocol = l4_protocol;
+ ip4->checksum = ip4_header_checksum (ip4);
+
+ return 0;
+}
+
#endif /* __included_ip6_to_ip4_h__ */
/*
Code Review / vpp.git / blobdiff