diff options
Diffstat (limited to 'tools/ebpf/rss.bpf.c')
| -rw-r--r-- | tools/ebpf/rss.bpf.c | 571 |
1 files changed, 571 insertions, 0 deletions
diff --git a/tools/ebpf/rss.bpf.c b/tools/ebpf/rss.bpf.c new file mode 100644 index 0000000000..e85ec55f9b --- /dev/null +++ b/tools/ebpf/rss.bpf.c @@ -0,0 +1,571 @@ +/* + * eBPF RSS program + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Andrew Melnychenko <andrew@daynix.com> + * Yuri Benditovich <yuri.benditovich@daynix.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + * Prepare: + * Requires llvm, clang, bpftool, linux kernel tree + * + * Build rss.bpf.skeleton.h: + * make -f Makefile.ebpf clean all + */ + +#include <stddef.h> +#include <stdbool.h> +#include <linux/bpf.h> + +#include <linux/in.h> +#include <linux/if_ether.h> +#include <linux/ip.h> +#include <linux/ipv6.h> + +#include <linux/udp.h> +#include <linux/tcp.h> + +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> +#include <linux/virtio_net.h> + +#define INDIRECTION_TABLE_SIZE 128 +#define HASH_CALCULATION_BUFFER_SIZE 36 + +struct rss_config_t { + __u8 redirect; + __u8 populate_hash; + __u32 hash_types; + __u16 indirections_len; + __u16 default_queue; +} __attribute__((packed)); + +struct toeplitz_key_data_t { + __u32 leftmost_32_bits; + __u8 next_byte[HASH_CALCULATION_BUFFER_SIZE]; +}; + +struct packet_hash_info_t { + __u8 is_ipv4; + __u8 is_ipv6; + __u8 is_udp; + __u8 is_tcp; + __u8 is_ipv6_ext_src; + __u8 is_ipv6_ext_dst; + __u8 is_fragmented; + + __u16 src_port; + __u16 dst_port; + + union { + struct { + __be32 in_src; + __be32 in_dst; + }; + + struct { + struct in6_addr in6_src; + struct in6_addr in6_dst; + struct in6_addr in6_ext_src; + struct in6_addr in6_ext_dst; + }; + }; +}; + +struct bpf_map_def SEC("maps") +tap_rss_map_configurations = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(struct rss_config_t), + .max_entries = 1, +}; + +struct bpf_map_def SEC("maps") +tap_rss_map_toeplitz_key = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(struct toeplitz_key_data_t), + .max_entries = 1, +}; + +struct bpf_map_def SEC("maps") +tap_rss_map_indirection_table = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(__u32), + .value_size = sizeof(__u16), + .max_entries = INDIRECTION_TABLE_SIZE, +}; + +static inline void net_rx_rss_add_chunk(__u8 *rss_input, size_t *bytes_written, + const void *ptr, size_t size) { + __builtin_memcpy(&rss_input[*bytes_written], ptr, size); + *bytes_written += size; +} + +static inline +void net_toeplitz_add(__u32 *result, + __u8 *input, + __u32 len + , struct toeplitz_key_data_t *key) { + + __u32 accumulator = *result; + __u32 leftmost_32_bits = key->leftmost_32_bits; + __u32 byte; + + for (byte = 0; byte < HASH_CALCULATION_BUFFER_SIZE; byte++) { + __u8 input_byte = input[byte]; + __u8 key_byte = key->next_byte[byte]; + __u8 bit; + + for (bit = 0; bit < 8; bit++) { + if (input_byte & (1 << 7)) { + accumulator ^= leftmost_32_bits; + } + + leftmost_32_bits = + (leftmost_32_bits << 1) | ((key_byte & (1 << 7)) >> 7); + + input_byte <<= 1; + key_byte <<= 1; + } + } + + *result = accumulator; +} + + +static inline int ip6_extension_header_type(__u8 hdr_type) +{ + switch (hdr_type) { + case IPPROTO_HOPOPTS: + case IPPROTO_ROUTING: + case IPPROTO_FRAGMENT: + case IPPROTO_ICMPV6: + case IPPROTO_NONE: + case IPPROTO_DSTOPTS: + case IPPROTO_MH: + return 1; + default: + return 0; + } +} +/* + * According to + * https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml + * we expect that there are would be no more than 11 extensions in IPv6 header, + * also there is 27 TLV options for Destination and Hop-by-hop extensions. + * Need to choose reasonable amount of maximum extensions/options we may + * check to find ext src/dst. + */ +#define IP6_EXTENSIONS_COUNT 11 +#define IP6_OPTIONS_COUNT 30 + +static inline int parse_ipv6_ext(struct __sk_buff *skb, + struct packet_hash_info_t *info, + __u8 *l4_protocol, size_t *l4_offset) +{ + int err = 0; + + if (!ip6_extension_header_type(*l4_protocol)) { + return 0; + } + + struct ipv6_opt_hdr ext_hdr = {}; + + for (unsigned int i = 0; i < IP6_EXTENSIONS_COUNT; ++i) { + + err = bpf_skb_load_bytes_relative(skb, *l4_offset, &ext_hdr, + sizeof(ext_hdr), BPF_HDR_START_NET); + if (err) { + goto error; + } + + if (*l4_protocol == IPPROTO_ROUTING) { + struct ipv6_rt_hdr ext_rt = {}; + + err = bpf_skb_load_bytes_relative(skb, *l4_offset, &ext_rt, + sizeof(ext_rt), BPF_HDR_START_NET); + if (err) { + goto error; + } + + if ((ext_rt.type == IPV6_SRCRT_TYPE_2) && + (ext_rt.hdrlen == sizeof(struct in6_addr) / 8) && + (ext_rt.segments_left == 1)) { + + err = bpf_skb_load_bytes_relative(skb, + *l4_offset + offsetof(struct rt2_hdr, addr), + &info->in6_ext_dst, sizeof(info->in6_ext_dst), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->is_ipv6_ext_dst = 1; + } + + } else if (*l4_protocol == IPPROTO_DSTOPTS) { + struct ipv6_opt_t { + __u8 type; + __u8 length; + } __attribute__((packed)) opt = {}; + + size_t opt_offset = sizeof(ext_hdr); + + for (unsigned int j = 0; j < IP6_OPTIONS_COUNT; ++j) { + err = bpf_skb_load_bytes_relative(skb, *l4_offset + opt_offset, + &opt, sizeof(opt), BPF_HDR_START_NET); + if (err) { + goto error; + } + + if (opt.type == IPV6_TLV_HAO) { + err = bpf_skb_load_bytes_relative(skb, + *l4_offset + opt_offset + + offsetof(struct ipv6_destopt_hao, addr), + &info->in6_ext_src, sizeof(info->in6_ext_src), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->is_ipv6_ext_src = 1; + break; + } + + opt_offset += (opt.type == IPV6_TLV_PAD1) ? + 1 : opt.length + sizeof(opt); + + if (opt_offset + 1 >= ext_hdr.hdrlen * 8) { + break; + } + } + } else if (*l4_protocol == IPPROTO_FRAGMENT) { + info->is_fragmented = true; + } + + *l4_protocol = ext_hdr.nexthdr; + *l4_offset += (ext_hdr.hdrlen + 1) * 8; + + if (!ip6_extension_header_type(ext_hdr.nexthdr)) { + return 0; + } + } + + return 0; +error: + return err; +} + +static __be16 parse_eth_type(struct __sk_buff *skb) +{ + unsigned int offset = 12; + __be16 ret = 0; + int err = 0; + + err = bpf_skb_load_bytes_relative(skb, offset, &ret, sizeof(ret), + BPF_HDR_START_MAC); + if (err) { + return 0; + } + + switch (bpf_ntohs(ret)) { + case ETH_P_8021AD: + offset += 4; + case ETH_P_8021Q: + offset += 4; + err = bpf_skb_load_bytes_relative(skb, offset, &ret, sizeof(ret), + BPF_HDR_START_MAC); + default: + break; + } + + if (err) { + return 0; + } + + return ret; +} + +static inline int parse_packet(struct __sk_buff *skb, + struct packet_hash_info_t *info) +{ + int err = 0; + + if (!info || !skb) { + return -1; + } + + size_t l4_offset = 0; + __u8 l4_protocol = 0; + __u16 l3_protocol = bpf_ntohs(parse_eth_type(skb)); + if (l3_protocol == 0) { + err = -1; + goto error; + } + + if (l3_protocol == ETH_P_IP) { + info->is_ipv4 = 1; + + struct iphdr ip = {}; + err = bpf_skb_load_bytes_relative(skb, 0, &ip, sizeof(ip), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->in_src = ip.saddr; + info->in_dst = ip.daddr; + info->is_fragmented = !!ip.frag_off; + + l4_protocol = ip.protocol; + l4_offset = ip.ihl * 4; + } else if (l3_protocol == ETH_P_IPV6) { + info->is_ipv6 = 1; + + struct ipv6hdr ip6 = {}; + err = bpf_skb_load_bytes_relative(skb, 0, &ip6, sizeof(ip6), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->in6_src = ip6.saddr; + info->in6_dst = ip6.daddr; + + l4_protocol = ip6.nexthdr; + l4_offset = sizeof(ip6); + + err = parse_ipv6_ext(skb, info, &l4_protocol, &l4_offset); + if (err) { + goto error; + } + } + + if (l4_protocol != 0 && !info->is_fragmented) { + if (l4_protocol == IPPROTO_TCP) { + info->is_tcp = 1; + + struct tcphdr tcp = {}; + err = bpf_skb_load_bytes_relative(skb, l4_offset, &tcp, sizeof(tcp), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->src_port = tcp.source; + info->dst_port = tcp.dest; + } else if (l4_protocol == IPPROTO_UDP) { /* TODO: add udplite? */ + info->is_udp = 1; + + struct udphdr udp = {}; + err = bpf_skb_load_bytes_relative(skb, l4_offset, &udp, sizeof(udp), + BPF_HDR_START_NET); + if (err) { + goto error; + } + + info->src_port = udp.source; + info->dst_port = udp.dest; + } + } + + return 0; + +error: + return err; +} + +static inline __u32 calculate_rss_hash(struct __sk_buff *skb, + struct rss_config_t *config, struct toeplitz_key_data_t *toe) +{ + __u8 rss_input[HASH_CALCULATION_BUFFER_SIZE] = {}; + size_t bytes_written = 0; + __u32 result = 0; + int err = 0; + struct packet_hash_info_t packet_info = {}; + + err = parse_packet(skb, &packet_info); + if (err) { + return 0; + } + + if (packet_info.is_ipv4) { + if (packet_info.is_tcp && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_TCPv4) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_src, + sizeof(packet_info.in_src)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_dst, + sizeof(packet_info.in_dst)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.src_port, + sizeof(packet_info.src_port)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.dst_port, + sizeof(packet_info.dst_port)); + } else if (packet_info.is_udp && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_UDPv4) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_src, + sizeof(packet_info.in_src)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_dst, + sizeof(packet_info.in_dst)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.src_port, + sizeof(packet_info.src_port)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.dst_port, + sizeof(packet_info.dst_port)); + } else if (config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_IPv4) { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_src, + sizeof(packet_info.in_src)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in_dst, + sizeof(packet_info.in_dst)); + } + } else if (packet_info.is_ipv6) { + if (packet_info.is_tcp && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_TCPv6) { + + if (packet_info.is_ipv6_ext_src && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_TCP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_src, + sizeof(packet_info.in6_ext_src)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_src, + sizeof(packet_info.in6_src)); + } + if (packet_info.is_ipv6_ext_dst && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_TCP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_dst, + sizeof(packet_info.in6_ext_dst)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_dst, + sizeof(packet_info.in6_dst)); + } + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.src_port, + sizeof(packet_info.src_port)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.dst_port, + sizeof(packet_info.dst_port)); + } else if (packet_info.is_udp && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_UDPv6) { + + if (packet_info.is_ipv6_ext_src && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_UDP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_src, + sizeof(packet_info.in6_ext_src)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_src, + sizeof(packet_info.in6_src)); + } + if (packet_info.is_ipv6_ext_dst && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_UDP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_dst, + sizeof(packet_info.in6_ext_dst)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_dst, + sizeof(packet_info.in6_dst)); + } + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.src_port, + sizeof(packet_info.src_port)); + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.dst_port, + sizeof(packet_info.dst_port)); + + } else if (config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_IPv6) { + if (packet_info.is_ipv6_ext_src && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_IP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_src, + sizeof(packet_info.in6_ext_src)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_src, + sizeof(packet_info.in6_src)); + } + if (packet_info.is_ipv6_ext_dst && + config->hash_types & VIRTIO_NET_RSS_HASH_TYPE_IP_EX) { + + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_ext_dst, + sizeof(packet_info.in6_ext_dst)); + } else { + net_rx_rss_add_chunk(rss_input, &bytes_written, + &packet_info.in6_dst, + sizeof(packet_info.in6_dst)); + } + } + } + + if (bytes_written) { + net_toeplitz_add(&result, rss_input, bytes_written, toe); + } + + return result; +} + +SEC("tun_rss_steering") +int tun_rss_steering_prog(struct __sk_buff *skb) +{ + + struct rss_config_t *config; + struct toeplitz_key_data_t *toe; + + __u32 key = 0; + __u32 hash = 0; + + config = bpf_map_lookup_elem(&tap_rss_map_configurations, &key); + toe = bpf_map_lookup_elem(&tap_rss_map_toeplitz_key, &key); + + if (config && toe) { + if (!config->redirect) { + return config->default_queue; + } + + hash = calculate_rss_hash(skb, config, toe); + if (hash) { + __u32 table_idx = hash % config->indirections_len; + __u16 *queue = 0; + + queue = bpf_map_lookup_elem(&tap_rss_map_indirection_table, + &table_idx); + + if (queue) { + return *queue; + } + } + + return config->default_queue; + } + + return -1; +} + +char _license[] SEC("license") = "GPL v2"; 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