diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2021-09-11 00:38:47 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2021-09-11 00:38:47 +0200 |
commit | c2f4954c2d3fc4f77b46c67585e17a58df4ba8e4 (patch) | |
tree | 533a2077028e02a851e51ad509a0aa3a9107999f /samples/bpf/xdp_redirect_cpu.bpf.c | |
parent | drivers: base: cacheinfo: Get rid of DEFINE_SMP_CALL_CACHE_FUNCTION() (diff) | |
parent | Merge tag 'acpi-5.15-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm (diff) | |
download | linux-dev-c2f4954c2d3fc4f77b46c67585e17a58df4ba8e4.tar.xz linux-dev-c2f4954c2d3fc4f77b46c67585e17a58df4ba8e4.zip |
Merge branch 'linus' into smp/urgent
Ensure that all usage sites of get/put_online_cpus() except for the
struggler in drivers/thermal are gone. So the last user and the deprecated
inlines can be removed.
Diffstat (limited to 'samples/bpf/xdp_redirect_cpu.bpf.c')
-rw-r--r-- | samples/bpf/xdp_redirect_cpu.bpf.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/samples/bpf/xdp_redirect_cpu.bpf.c b/samples/bpf/xdp_redirect_cpu.bpf.c new file mode 100644 index 000000000000..f10fe3cf25f6 --- /dev/null +++ b/samples/bpf/xdp_redirect_cpu.bpf.c @@ -0,0 +1,541 @@ +/* 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; + u16 dport; + + 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; + + dport = bpf_ntohs(udph->dest); + return dport; +} + +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"; |