| /* |
| * QEMU network structures definitions and helper functions |
| * |
| * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com) |
| * |
| * Developed by Daynix Computing LTD (http://www.daynix.com) |
| * |
| * Authors: |
| * Dmitry Fleytman <dmitry@daynix.com> |
| * Tamir Shomer <tamirs@daynix.com> |
| * Yan Vugenfirer <yan@daynix.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| * See the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include "net/eth.h" |
| #include "net/checksum.h" |
| #include "qemu-common.h" |
| #include "net/tap.h" |
| |
| void eth_setup_vlan_headers(struct eth_header *ehdr, uint16_t vlan_tag, |
| bool *is_new) |
| { |
| struct vlan_header *vhdr = PKT_GET_VLAN_HDR(ehdr); |
| |
| switch (be16_to_cpu(ehdr->h_proto)) { |
| case ETH_P_VLAN: |
| case ETH_P_DVLAN: |
| /* vlan hdr exists */ |
| *is_new = false; |
| break; |
| |
| default: |
| /* No VLAN header, put a new one */ |
| vhdr->h_proto = ehdr->h_proto; |
| ehdr->h_proto = cpu_to_be16(ETH_P_VLAN); |
| *is_new = true; |
| break; |
| } |
| vhdr->h_tci = cpu_to_be16(vlan_tag); |
| } |
| |
| uint8_t |
| eth_get_gso_type(uint16_t l3_proto, uint8_t *l3_hdr, uint8_t l4proto) |
| { |
| uint8_t ecn_state = 0; |
| |
| if (l3_proto == ETH_P_IP) { |
| struct ip_header *iphdr = (struct ip_header *) l3_hdr; |
| |
| if (IP_HEADER_VERSION(iphdr) == IP_HEADER_VERSION_4) { |
| if (IPTOS_ECN(iphdr->ip_tos) == IPTOS_ECN_CE) { |
| ecn_state = VIRTIO_NET_HDR_GSO_ECN; |
| } |
| if (l4proto == IP_PROTO_TCP) { |
| return VIRTIO_NET_HDR_GSO_TCPV4 | ecn_state; |
| } else if (l4proto == IP_PROTO_UDP) { |
| return VIRTIO_NET_HDR_GSO_UDP | ecn_state; |
| } |
| } |
| } else if (l3_proto == ETH_P_IPV6) { |
| struct ip6_header *ip6hdr = (struct ip6_header *) l3_hdr; |
| |
| if (IP6_ECN(ip6hdr->ip6_ecn_acc) == IP6_ECN_CE) { |
| ecn_state = VIRTIO_NET_HDR_GSO_ECN; |
| } |
| |
| if (l4proto == IP_PROTO_TCP) { |
| return VIRTIO_NET_HDR_GSO_TCPV6 | ecn_state; |
| } |
| } |
| |
| /* Unsupported offload */ |
| g_assert_not_reached(); |
| |
| return VIRTIO_NET_HDR_GSO_NONE | ecn_state; |
| } |
| |
| void eth_get_protocols(const uint8_t *headers, |
| uint32_t hdr_length, |
| bool *isip4, bool *isip6, |
| bool *isudp, bool *istcp) |
| { |
| int proto; |
| size_t l2hdr_len = eth_get_l2_hdr_length(headers); |
| assert(hdr_length >= eth_get_l2_hdr_length(headers)); |
| *isip4 = *isip6 = *isudp = *istcp = false; |
| |
| proto = eth_get_l3_proto(headers, l2hdr_len); |
| if (proto == ETH_P_IP) { |
| *isip4 = true; |
| |
| struct ip_header *iphdr; |
| |
| assert(hdr_length >= |
| eth_get_l2_hdr_length(headers) + sizeof(struct ip_header)); |
| |
| iphdr = PKT_GET_IP_HDR(headers); |
| |
| if (IP_HEADER_VERSION(iphdr) == IP_HEADER_VERSION_4) { |
| if (iphdr->ip_p == IP_PROTO_TCP) { |
| *istcp = true; |
| } else if (iphdr->ip_p == IP_PROTO_UDP) { |
| *isudp = true; |
| } |
| } |
| } else if (proto == ETH_P_IPV6) { |
| uint8_t l4proto; |
| size_t full_ip6hdr_len; |
| |
| struct iovec hdr_vec; |
| hdr_vec.iov_base = (void *) headers; |
| hdr_vec.iov_len = hdr_length; |
| |
| *isip6 = true; |
| if (eth_parse_ipv6_hdr(&hdr_vec, 1, l2hdr_len, |
| &l4proto, &full_ip6hdr_len)) { |
| if (l4proto == IP_PROTO_TCP) { |
| *istcp = true; |
| } else if (l4proto == IP_PROTO_UDP) { |
| *isudp = true; |
| } |
| } |
| } |
| } |
| |
| void |
| eth_setup_ip4_fragmentation(const void *l2hdr, size_t l2hdr_len, |
| void *l3hdr, size_t l3hdr_len, |
| size_t l3payload_len, |
| size_t frag_offset, bool more_frags) |
| { |
| if (eth_get_l3_proto(l2hdr, l2hdr_len) == ETH_P_IP) { |
| uint16_t orig_flags; |
| struct ip_header *iphdr = (struct ip_header *) l3hdr; |
| uint16_t frag_off_units = frag_offset / IP_FRAG_UNIT_SIZE; |
| uint16_t new_ip_off; |
| |
| assert(frag_offset % IP_FRAG_UNIT_SIZE == 0); |
| assert((frag_off_units & ~IP_OFFMASK) == 0); |
| |
| orig_flags = be16_to_cpu(iphdr->ip_off) & ~(IP_OFFMASK|IP_MF); |
| new_ip_off = frag_off_units | orig_flags | (more_frags ? IP_MF : 0); |
| iphdr->ip_off = cpu_to_be16(new_ip_off); |
| iphdr->ip_len = cpu_to_be16(l3payload_len + l3hdr_len); |
| } |
| } |
| |
| void |
| eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len) |
| { |
| struct ip_header *iphdr = (struct ip_header *) l3hdr; |
| iphdr->ip_sum = 0; |
| iphdr->ip_sum = cpu_to_be16(net_raw_checksum(l3hdr, l3hdr_len)); |
| } |
| |
| uint32_t |
| eth_calc_pseudo_hdr_csum(struct ip_header *iphdr, uint16_t csl) |
| { |
| struct ip_pseudo_header ipph; |
| ipph.ip_src = iphdr->ip_src; |
| ipph.ip_dst = iphdr->ip_dst; |
| ipph.ip_payload = cpu_to_be16(csl); |
| ipph.ip_proto = iphdr->ip_p; |
| ipph.zeros = 0; |
| return net_checksum_add(sizeof(ipph), (uint8_t *) &ipph); |
| } |
| |
| static bool |
| eth_is_ip6_extension_header_type(uint8_t hdr_type) |
| { |
| switch (hdr_type) { |
| case IP6_HOP_BY_HOP: |
| case IP6_ROUTING: |
| case IP6_FRAGMENT: |
| case IP6_ESP: |
| case IP6_AUTHENTICATION: |
| case IP6_DESTINATON: |
| case IP6_MOBILITY: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| bool eth_parse_ipv6_hdr(struct iovec *pkt, int pkt_frags, |
| size_t ip6hdr_off, uint8_t *l4proto, |
| size_t *full_hdr_len) |
| { |
| struct ip6_header ip6_hdr; |
| struct ip6_ext_hdr ext_hdr; |
| size_t bytes_read; |
| |
| bytes_read = iov_to_buf(pkt, pkt_frags, ip6hdr_off, |
| &ip6_hdr, sizeof(ip6_hdr)); |
| if (bytes_read < sizeof(ip6_hdr)) { |
| return false; |
| } |
| |
| *full_hdr_len = sizeof(struct ip6_header); |
| |
| if (!eth_is_ip6_extension_header_type(ip6_hdr.ip6_nxt)) { |
| *l4proto = ip6_hdr.ip6_nxt; |
| return true; |
| } |
| |
| do { |
| bytes_read = iov_to_buf(pkt, pkt_frags, ip6hdr_off + *full_hdr_len, |
| &ext_hdr, sizeof(ext_hdr)); |
| *full_hdr_len += (ext_hdr.ip6r_len + 1) * IP6_EXT_GRANULARITY; |
| } while (eth_is_ip6_extension_header_type(ext_hdr.ip6r_nxt)); |
| |
| *l4proto = ext_hdr.ip6r_nxt; |
| return true; |
| } |