| /* XDP redirect to CPUs via cpumap (BPF_MAP_TYPE_CPUMAP) |
| * |
| * GPLv2, Copyright(c) 2017 Jesper Dangaard Brouer, Red Hat, Inc. |
| */ |
| #include "vmlinux.h" |
| #include "xdp_sample.bpf.h" |
| #include "xdp_sample_shared.h" |
| #include "hash_func01.h" |
| |
| /* Special map type that can XDP_REDIRECT frames to another CPU */ |
| struct { |
| __uint(type, BPF_MAP_TYPE_CPUMAP); |
| __uint(key_size, sizeof(u32)); |
| __uint(value_size, sizeof(struct bpf_cpumap_val)); |
| } cpu_map SEC(".maps"); |
| |
| /* Set of maps controlling available CPU, and for iterating through |
| * selectable redirect CPUs. |
| */ |
| struct { |
| __uint(type, BPF_MAP_TYPE_ARRAY); |
| __type(key, u32); |
| __type(value, u32); |
| } cpus_available SEC(".maps"); |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_ARRAY); |
| __type(key, u32); |
| __type(value, u32); |
| __uint(max_entries, 1); |
| } cpus_count SEC(".maps"); |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); |
| __type(key, u32); |
| __type(value, u32); |
| __uint(max_entries, 1); |
| } cpus_iterator SEC(".maps"); |
| |
| struct { |
| __uint(type, BPF_MAP_TYPE_DEVMAP); |
| __uint(key_size, sizeof(int)); |
| __uint(value_size, sizeof(struct bpf_devmap_val)); |
| __uint(max_entries, 1); |
| } tx_port SEC(".maps"); |
| |
| char tx_mac_addr[ETH_ALEN]; |
| |
| /* Helper parse functions */ |
| |
| static __always_inline |
| bool parse_eth(struct ethhdr *eth, void *data_end, |
| u16 *eth_proto, u64 *l3_offset) |
| { |
| u16 eth_type; |
| u64 offset; |
| |
| offset = sizeof(*eth); |
| if ((void *)eth + offset > data_end) |
| return false; |
| |
| eth_type = eth->h_proto; |
| |
| /* Skip non 802.3 Ethertypes */ |
| if (__builtin_expect(bpf_ntohs(eth_type) < ETH_P_802_3_MIN, 0)) |
| return false; |
| |
| /* Handle VLAN tagged packet */ |
| if (eth_type == bpf_htons(ETH_P_8021Q) || |
| eth_type == bpf_htons(ETH_P_8021AD)) { |
| struct vlan_hdr *vlan_hdr; |
| |
| vlan_hdr = (void *)eth + offset; |
| offset += sizeof(*vlan_hdr); |
| if ((void *)eth + offset > data_end) |
| return false; |
| eth_type = vlan_hdr->h_vlan_encapsulated_proto; |
| } |
| /* Handle double VLAN tagged packet */ |
| if (eth_type == bpf_htons(ETH_P_8021Q) || |
| eth_type == bpf_htons(ETH_P_8021AD)) { |
| struct vlan_hdr *vlan_hdr; |
| |
| vlan_hdr = (void *)eth + offset; |
| offset += sizeof(*vlan_hdr); |
| if ((void *)eth + offset > data_end) |
| return false; |
| eth_type = vlan_hdr->h_vlan_encapsulated_proto; |
| } |
| |
| *eth_proto = bpf_ntohs(eth_type); |
| *l3_offset = offset; |
| return true; |
| } |
| |
| static __always_inline |
| u16 get_dest_port_ipv4_udp(struct xdp_md *ctx, u64 nh_off) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct iphdr *iph = data + nh_off; |
| struct udphdr *udph; |
| |
| if (iph + 1 > data_end) |
| return 0; |
| if (!(iph->protocol == IPPROTO_UDP)) |
| return 0; |
| |
| udph = (void *)(iph + 1); |
| if (udph + 1 > data_end) |
| return 0; |
| |
| return bpf_ntohs(udph->dest); |
| } |
| |
| static __always_inline |
| int get_proto_ipv4(struct xdp_md *ctx, u64 nh_off) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct iphdr *iph = data + nh_off; |
| |
| if (iph + 1 > data_end) |
| return 0; |
| return iph->protocol; |
| } |
| |
| static __always_inline |
| int get_proto_ipv6(struct xdp_md *ctx, u64 nh_off) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct ipv6hdr *ip6h = data + nh_off; |
| |
| if (ip6h + 1 > data_end) |
| return 0; |
| return ip6h->nexthdr; |
| } |
| |
| SEC("xdp") |
| int xdp_prognum0_no_touch(struct xdp_md *ctx) |
| { |
| u32 key = bpf_get_smp_processor_id(); |
| struct datarec *rec; |
| u32 *cpu_selected; |
| u32 cpu_dest = 0; |
| u32 key0 = 0; |
| |
| /* Only use first entry in cpus_available */ |
| cpu_selected = bpf_map_lookup_elem(&cpus_available, &key0); |
| if (!cpu_selected) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_selected; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| SEC("xdp") |
| int xdp_prognum1_touch_data(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| u32 key = bpf_get_smp_processor_id(); |
| struct ethhdr *eth = data; |
| struct datarec *rec; |
| u32 *cpu_selected; |
| u32 cpu_dest = 0; |
| u32 key0 = 0; |
| u16 eth_type; |
| |
| /* Only use first entry in cpus_available */ |
| cpu_selected = bpf_map_lookup_elem(&cpus_available, &key0); |
| if (!cpu_selected) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_selected; |
| |
| /* Validate packet length is minimum Eth header size */ |
| if (eth + 1 > data_end) |
| return XDP_ABORTED; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| /* Read packet data, and use it (drop non 802.3 Ethertypes) */ |
| eth_type = eth->h_proto; |
| if (bpf_ntohs(eth_type) < ETH_P_802_3_MIN) { |
| NO_TEAR_INC(rec->dropped); |
| return XDP_DROP; |
| } |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| SEC("xdp") |
| int xdp_prognum2_round_robin(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| u32 key = bpf_get_smp_processor_id(); |
| struct datarec *rec; |
| u32 cpu_dest = 0; |
| u32 key0 = 0; |
| |
| u32 *cpu_selected; |
| u32 *cpu_iterator; |
| u32 *cpu_max; |
| u32 cpu_idx; |
| |
| cpu_max = bpf_map_lookup_elem(&cpus_count, &key0); |
| if (!cpu_max) |
| return XDP_ABORTED; |
| |
| cpu_iterator = bpf_map_lookup_elem(&cpus_iterator, &key0); |
| if (!cpu_iterator) |
| return XDP_ABORTED; |
| cpu_idx = *cpu_iterator; |
| |
| *cpu_iterator += 1; |
| if (*cpu_iterator == *cpu_max) |
| *cpu_iterator = 0; |
| |
| cpu_selected = bpf_map_lookup_elem(&cpus_available, &cpu_idx); |
| if (!cpu_selected) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_selected; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| SEC("xdp") |
| int xdp_prognum3_proto_separate(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| u32 key = bpf_get_smp_processor_id(); |
| struct ethhdr *eth = data; |
| u8 ip_proto = IPPROTO_UDP; |
| struct datarec *rec; |
| u16 eth_proto = 0; |
| u64 l3_offset = 0; |
| u32 cpu_dest = 0; |
| u32 *cpu_lookup; |
| u32 cpu_idx = 0; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| if (!(parse_eth(eth, data_end, ð_proto, &l3_offset))) |
| return XDP_PASS; /* Just skip */ |
| |
| /* Extract L4 protocol */ |
| switch (eth_proto) { |
| case ETH_P_IP: |
| ip_proto = get_proto_ipv4(ctx, l3_offset); |
| break; |
| case ETH_P_IPV6: |
| ip_proto = get_proto_ipv6(ctx, l3_offset); |
| break; |
| case ETH_P_ARP: |
| cpu_idx = 0; /* ARP packet handled on separate CPU */ |
| break; |
| default: |
| cpu_idx = 0; |
| } |
| |
| /* Choose CPU based on L4 protocol */ |
| switch (ip_proto) { |
| case IPPROTO_ICMP: |
| case IPPROTO_ICMPV6: |
| cpu_idx = 2; |
| break; |
| case IPPROTO_TCP: |
| cpu_idx = 0; |
| break; |
| case IPPROTO_UDP: |
| cpu_idx = 1; |
| break; |
| default: |
| cpu_idx = 0; |
| } |
| |
| cpu_lookup = bpf_map_lookup_elem(&cpus_available, &cpu_idx); |
| if (!cpu_lookup) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_lookup; |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| SEC("xdp") |
| int xdp_prognum4_ddos_filter_pktgen(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| u32 key = bpf_get_smp_processor_id(); |
| struct ethhdr *eth = data; |
| u8 ip_proto = IPPROTO_UDP; |
| struct datarec *rec; |
| u16 eth_proto = 0; |
| u64 l3_offset = 0; |
| u32 cpu_dest = 0; |
| u32 *cpu_lookup; |
| u32 cpu_idx = 0; |
| u16 dest_port; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| if (!(parse_eth(eth, data_end, ð_proto, &l3_offset))) |
| return XDP_PASS; /* Just skip */ |
| |
| /* Extract L4 protocol */ |
| switch (eth_proto) { |
| case ETH_P_IP: |
| ip_proto = get_proto_ipv4(ctx, l3_offset); |
| break; |
| case ETH_P_IPV6: |
| ip_proto = get_proto_ipv6(ctx, l3_offset); |
| break; |
| case ETH_P_ARP: |
| cpu_idx = 0; /* ARP packet handled on separate CPU */ |
| break; |
| default: |
| cpu_idx = 0; |
| } |
| |
| /* Choose CPU based on L4 protocol */ |
| switch (ip_proto) { |
| case IPPROTO_ICMP: |
| case IPPROTO_ICMPV6: |
| cpu_idx = 2; |
| break; |
| case IPPROTO_TCP: |
| cpu_idx = 0; |
| break; |
| case IPPROTO_UDP: |
| cpu_idx = 1; |
| /* DDoS filter UDP port 9 (pktgen) */ |
| dest_port = get_dest_port_ipv4_udp(ctx, l3_offset); |
| if (dest_port == 9) { |
| NO_TEAR_INC(rec->dropped); |
| return XDP_DROP; |
| } |
| break; |
| default: |
| cpu_idx = 0; |
| } |
| |
| cpu_lookup = bpf_map_lookup_elem(&cpus_available, &cpu_idx); |
| if (!cpu_lookup) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_lookup; |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| /* Hashing initval */ |
| #define INITVAL 15485863 |
| |
| static __always_inline |
| u32 get_ipv4_hash_ip_pair(struct xdp_md *ctx, u64 nh_off) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct iphdr *iph = data + nh_off; |
| u32 cpu_hash; |
| |
| if (iph + 1 > data_end) |
| return 0; |
| |
| cpu_hash = iph->saddr + iph->daddr; |
| cpu_hash = SuperFastHash((char *)&cpu_hash, 4, INITVAL + iph->protocol); |
| |
| return cpu_hash; |
| } |
| |
| static __always_inline |
| u32 get_ipv6_hash_ip_pair(struct xdp_md *ctx, u64 nh_off) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct ipv6hdr *ip6h = data + nh_off; |
| u32 cpu_hash; |
| |
| if (ip6h + 1 > data_end) |
| return 0; |
| |
| cpu_hash = ip6h->saddr.in6_u.u6_addr32[0] + ip6h->daddr.in6_u.u6_addr32[0]; |
| cpu_hash += ip6h->saddr.in6_u.u6_addr32[1] + ip6h->daddr.in6_u.u6_addr32[1]; |
| cpu_hash += ip6h->saddr.in6_u.u6_addr32[2] + ip6h->daddr.in6_u.u6_addr32[2]; |
| cpu_hash += ip6h->saddr.in6_u.u6_addr32[3] + ip6h->daddr.in6_u.u6_addr32[3]; |
| cpu_hash = SuperFastHash((char *)&cpu_hash, 4, INITVAL + ip6h->nexthdr); |
| |
| return cpu_hash; |
| } |
| |
| /* Load-Balance traffic based on hashing IP-addrs + L4-proto. The |
| * hashing scheme is symmetric, meaning swapping IP src/dest still hit |
| * same CPU. |
| */ |
| SEC("xdp") |
| int xdp_prognum5_lb_hash_ip_pairs(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| u32 key = bpf_get_smp_processor_id(); |
| struct ethhdr *eth = data; |
| struct datarec *rec; |
| u16 eth_proto = 0; |
| u64 l3_offset = 0; |
| u32 cpu_dest = 0; |
| u32 cpu_idx = 0; |
| u32 *cpu_lookup; |
| u32 key0 = 0; |
| u32 *cpu_max; |
| u32 cpu_hash; |
| |
| rec = bpf_map_lookup_elem(&rx_cnt, &key); |
| if (!rec) |
| return XDP_PASS; |
| NO_TEAR_INC(rec->processed); |
| |
| cpu_max = bpf_map_lookup_elem(&cpus_count, &key0); |
| if (!cpu_max) |
| return XDP_ABORTED; |
| |
| if (!(parse_eth(eth, data_end, ð_proto, &l3_offset))) |
| return XDP_PASS; /* Just skip */ |
| |
| /* Hash for IPv4 and IPv6 */ |
| switch (eth_proto) { |
| case ETH_P_IP: |
| cpu_hash = get_ipv4_hash_ip_pair(ctx, l3_offset); |
| break; |
| case ETH_P_IPV6: |
| cpu_hash = get_ipv6_hash_ip_pair(ctx, l3_offset); |
| break; |
| case ETH_P_ARP: /* ARP packet handled on CPU idx 0 */ |
| default: |
| cpu_hash = 0; |
| } |
| |
| /* Choose CPU based on hash */ |
| cpu_idx = cpu_hash % *cpu_max; |
| |
| cpu_lookup = bpf_map_lookup_elem(&cpus_available, &cpu_idx); |
| if (!cpu_lookup) |
| return XDP_ABORTED; |
| cpu_dest = *cpu_lookup; |
| |
| if (cpu_dest >= nr_cpus) { |
| NO_TEAR_INC(rec->issue); |
| return XDP_ABORTED; |
| } |
| return bpf_redirect_map(&cpu_map, cpu_dest, 0); |
| } |
| |
| SEC("xdp_cpumap/redirect") |
| int xdp_redirect_cpu_devmap(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct ethhdr *eth = data; |
| u64 nh_off; |
| |
| nh_off = sizeof(*eth); |
| if (data + nh_off > data_end) |
| return XDP_DROP; |
| |
| swap_src_dst_mac(data); |
| return bpf_redirect_map(&tx_port, 0, 0); |
| } |
| |
| SEC("xdp_cpumap/pass") |
| int xdp_redirect_cpu_pass(struct xdp_md *ctx) |
| { |
| return XDP_PASS; |
| } |
| |
| SEC("xdp_cpumap/drop") |
| int xdp_redirect_cpu_drop(struct xdp_md *ctx) |
| { |
| return XDP_DROP; |
| } |
| |
| SEC("xdp_devmap/egress") |
| int xdp_redirect_egress_prog(struct xdp_md *ctx) |
| { |
| void *data_end = (void *)(long)ctx->data_end; |
| void *data = (void *)(long)ctx->data; |
| struct ethhdr *eth = data; |
| u64 nh_off; |
| |
| nh_off = sizeof(*eth); |
| if (data + nh_off > data_end) |
| return XDP_DROP; |
| |
| __builtin_memcpy(eth->h_source, (const char *)tx_mac_addr, ETH_ALEN); |
| |
| return XDP_PASS; |
| } |
| |
| char _license[] SEC("license") = "GPL"; |
