diff options
Diffstat (limited to 'src/libnet_checksum.c')
| -rw-r--r-- | src/libnet_checksum.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/src/libnet_checksum.c b/src/libnet_checksum.c index 16995de..3bbcc36 100644 --- a/src/libnet_checksum.c +++ b/src/libnet_checksum.c @@ -526,6 +526,32 @@ libnet_inet_checksum(libnet_t *l, uint8_t *iphdr, int protocol, int h_len, const * the ISL frame itself. Use the libnet_crc function. */ } + case LIBNET_PROTO_UDLD: + { + /** + * Once again. + * iphdr points to the packet, which has the following structure: + * IEEE 802.3 Ethernet 14 bytes + * LLC 8 bytes + * UDLD <<<<---- udld_hdr_offset + */ + /* FIXME: should we use ptrdiff_t for pointer arithmetics? */ + int whole_packet_length = (end - iphdr); /* The length of IEEE 802.3 Ethernet + LLC + UDLD(include TLVs) */ + if (whole_packet_length < 0) + { + snprintf(l->err_buf, LIBNET_ERRBUF_SIZE, + "%s(): cannot calculate packet lenght", __func__); + return (-1); + } + const uint8_t udld_hdr_offset = (LIBNET_802_3_H + LIBNET_802_2SNAP_H); + int udld_packet_length = (whole_packet_length - udld_hdr_offset); + + const uint16_t checksum = libnet_ip_check((uint16_t *)iphdr + (udld_hdr_offset/sizeof(uint16_t)), udld_packet_length); + + struct libnet_udld_hdr *udld_hdr = (struct libnet_udld_hdr *)(iphdr + udld_hdr_offset); + udld_hdr->checksum = checksum; + break; + } default: { snprintf(l->err_buf, LIBNET_ERRBUF_SIZE, |