From: Ivan Boule Date: Thu, 28 May 2015 15:05:23 +0000 (+0200) Subject: app/testpmd: fix reply to a multicast ICMP request X-Git-Tag: spdx-start~9111 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=8443ce81935358111e078ade559c3c75cd5f7871;p=dpdk.git app/testpmd: fix reply to a multicast ICMP request Set the IP source and destination addresses in the IP header of the ICMP reply as follows: - Use the request IP source address as the reply IP destination address - If the request IP destination address is a multicast IP address - choose a reply IP source address different from the request IP source address, - re-compute the IP header checksum. Otherwise - switch the request IP source and destination addresses in the reply, - keep the IP header checksum unchanged. Signed-off-by: Ivan Boule --- diff --git a/app/test-pmd/icmpecho.c b/app/test-pmd/icmpecho.c index e249e7157e..29aef71115 100644 --- a/app/test-pmd/icmpecho.c +++ b/app/test-pmd/icmpecho.c @@ -272,6 +272,30 @@ ipv4_addr_dump(const char *what, uint32_t be_ipv4_addr) printf("%s", buf); } +static uint16_t +ipv4_hdr_cksum(struct ipv4_hdr *ip_h) +{ + uint16_t *v16_h; + uint32_t ip_cksum; + + /* + * Compute the sum of successive 16-bit words of the IPv4 header, + * skipping the checksum field of the header. + */ + v16_h = (uint16_t *) ip_h; + ip_cksum = v16_h[0] + v16_h[1] + v16_h[2] + v16_h[3] + + v16_h[4] + v16_h[6] + v16_h[7] + v16_h[8] + v16_h[9]; + + /* reduce 32 bit checksum to 16 bits and complement it */ + ip_cksum = (ip_cksum & 0xffff) + (ip_cksum >> 16); + ip_cksum = (ip_cksum & 0xffff) + (ip_cksum >> 16); + ip_cksum = (~ip_cksum) & 0x0000FFFF; + return (ip_cksum == 0) ? 0xFFFF : (uint16_t) ip_cksum; +} + +#define is_multicast_ipv4_addr(ipv4_addr) \ + (((rte_be_to_cpu_32((ipv4_addr)) >> 24) & 0x000000FF) == 0xE0) + /* * Receive a burst of packets, lookup for ICMP echo requets, and, if any, * send back ICMP echo replies. @@ -443,9 +467,18 @@ reply_to_icmp_echo_rqsts(struct fwd_stream *fs) /* * Prepare ICMP echo reply to be sent back. * - switch ethernet source and destinations addresses, - * - switch IPv4 source and destinations addresses, + * - use the request IP source address as the reply IP + * destination address, + * - if the request IP destination address is a multicast + * address: + * - choose a reply IP source address different from the + * request IP source address, + * - re-compute the IP header checksum. + * Otherwise: + * - switch the request IP source and destination + * addresses in the reply IP header, + * - keep the IP header checksum unchanged. * - set IP_ICMP_ECHO_REPLY in ICMP header. - * No need to re-compute the IP header checksum. * ICMP checksum is computed by assuming it is valid in the * echo request and not verified. */ @@ -453,8 +486,21 @@ reply_to_icmp_echo_rqsts(struct fwd_stream *fs) ether_addr_copy(ð_h->d_addr, ð_h->s_addr); ether_addr_copy(ð_addr, ð_h->d_addr); ip_addr = ip_h->src_addr; - ip_h->src_addr = ip_h->dst_addr; - ip_h->dst_addr = ip_addr; + if (is_multicast_ipv4_addr(ip_h->dst_addr)) { + uint32_t ip_src; + + ip_src = rte_be_to_cpu_32(ip_addr); + if ((ip_src & 0x00000003) == 1) + ip_src = (ip_src & 0xFFFFFFFC) | 0x00000002; + else + ip_src = (ip_src & 0xFFFFFFFC) | 0x00000001; + ip_h->src_addr = rte_cpu_to_be_32(ip_src); + ip_h->dst_addr = ip_addr; + ip_h->hdr_checksum = ipv4_hdr_cksum(ip_h); + } else { + ip_h->src_addr = ip_h->dst_addr; + ip_h->dst_addr = ip_addr; + } icmp_h->icmp_type = IP_ICMP_ECHO_REPLY; cksum = ~icmp_h->icmp_cksum & 0xffff; cksum += ~htons(IP_ICMP_ECHO_REQUEST << 8) & 0xffff;