diff options
Diffstat (limited to 'samples')
| -rw-r--r-- | samples/bpf/Makefile | 4 | ||||
| -rw-r--r-- | samples/bpf/sockex2_kern.c | 215 | ||||
| -rw-r--r-- | samples/bpf/sockex2_user.c | 44 |
3 files changed, 263 insertions, 0 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 770d145186c..b5b3600dcdf 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -5,20 +5,24 @@ obj- := dummy.o hostprogs-y := test_verifier test_maps hostprogs-y += sock_example hostprogs-y += sockex1 +hostprogs-y += sockex2 test_verifier-objs := test_verifier.o libbpf.o test_maps-objs := test_maps.o libbpf.o sock_example-objs := sock_example.o libbpf.o sockex1-objs := bpf_load.o libbpf.o sockex1_user.o +sockex2-objs := bpf_load.o libbpf.o sockex2_user.o # Tell kbuild to always build the programs always := $(hostprogs-y) always += sockex1_kern.o +always += sockex2_kern.o HOSTCFLAGS += -I$(objtree)/usr/include HOSTCFLAGS_bpf_load.o += -I$(objtree)/usr/include -Wno-unused-variable HOSTLOADLIBES_sockex1 += -lelf +HOSTLOADLIBES_sockex2 += -lelf # point this to your LLVM backend with bpf support LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc diff --git a/samples/bpf/sockex2_kern.c b/samples/bpf/sockex2_kern.c new file mode 100644 index 00000000000..6f0135f0f21 --- /dev/null +++ b/samples/bpf/sockex2_kern.c @@ -0,0 +1,215 @@ +#include <uapi/linux/bpf.h> +#include "bpf_helpers.h" +#include <uapi/linux/in.h> +#include <uapi/linux/if.h> +#include <uapi/linux/if_ether.h> +#include <uapi/linux/ip.h> +#include <uapi/linux/ipv6.h> +#include <uapi/linux/if_tunnel.h> +#define IP_MF 0x2000 +#define IP_OFFSET 0x1FFF + +struct vlan_hdr { + __be16 h_vlan_TCI; + __be16 h_vlan_encapsulated_proto; +}; + +struct flow_keys { + __be32 src; + __be32 dst; + union { + __be32 ports; + __be16 port16[2]; + }; + __u16 thoff; + __u8 ip_proto; +}; + +static inline int proto_ports_offset(__u64 proto) +{ + switch (proto) { + case IPPROTO_TCP: + case IPPROTO_UDP: + case IPPROTO_DCCP: + case IPPROTO_ESP: + case IPPROTO_SCTP: + case IPPROTO_UDPLITE: + return 0; + case IPPROTO_AH: + return 4; + default: + return 0; + } +} + +static inline int ip_is_fragment(struct sk_buff *ctx, __u64 nhoff) +{ + return load_half(ctx, nhoff + offsetof(struct iphdr, frag_off)) + & (IP_MF | IP_OFFSET); +} + +static inline __u32 ipv6_addr_hash(struct sk_buff *ctx, __u64 off) +{ + __u64 w0 = load_word(ctx, off); + __u64 w1 = load_word(ctx, off + 4); + __u64 w2 = load_word(ctx, off + 8); + __u64 w3 = load_word(ctx, off + 12); + + return (__u32)(w0 ^ w1 ^ w2 ^ w3); +} + +static inline __u64 parse_ip(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto, + struct flow_keys *flow) +{ + __u64 verlen; + + if (unlikely(ip_is_fragment(skb, nhoff))) + *ip_proto = 0; + else + *ip_proto = load_byte(skb, nhoff + offsetof(struct iphdr, protocol)); + + if (*ip_proto != IPPROTO_GRE) { + flow->src = load_word(skb, nhoff + offsetof(struct iphdr, saddr)); + flow->dst = load_word(skb, nhoff + offsetof(struct iphdr, daddr)); + } + + verlen = load_byte(skb, nhoff + 0/*offsetof(struct iphdr, ihl)*/); + if (likely(verlen == 0x45)) + nhoff += 20; + else + nhoff += (verlen & 0xF) << 2; + + return nhoff; +} + +static inline __u64 parse_ipv6(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto, + struct flow_keys *flow) +{ + *ip_proto = load_byte(skb, + nhoff + offsetof(struct ipv6hdr, nexthdr)); + flow->src = ipv6_addr_hash(skb, + nhoff + offsetof(struct ipv6hdr, saddr)); + flow->dst = ipv6_addr_hash(skb, + nhoff + offsetof(struct ipv6hdr, daddr)); + nhoff += sizeof(struct ipv6hdr); + + return nhoff; +} + +static inline bool flow_dissector(struct sk_buff *skb, struct flow_keys *flow) +{ + __u64 nhoff = ETH_HLEN; + __u64 ip_proto; + __u64 proto = load_half(skb, 12); + int poff; + + if (proto == ETH_P_8021AD) { + proto = load_half(skb, nhoff + offsetof(struct vlan_hdr, + h_vlan_encapsulated_proto)); + nhoff += sizeof(struct vlan_hdr); + } + + if (proto == ETH_P_8021Q) { + proto = load_half(skb, nhoff + offsetof(struct vlan_hdr, + h_vlan_encapsulated_proto)); + nhoff += sizeof(struct vlan_hdr); + } + + if (likely(proto == ETH_P_IP)) + nhoff = parse_ip(skb, nhoff, &ip_proto, flow); + else if (proto == ETH_P_IPV6) + nhoff = parse_ipv6(skb, nhoff, &ip_proto, flow); + else + return false; + + switch (ip_proto) { + case IPPROTO_GRE: { + struct gre_hdr { + __be16 flags; + __be16 proto; + }; + + __u64 gre_flags = load_half(skb, + nhoff + offsetof(struct gre_hdr, flags)); + __u64 gre_proto = load_half(skb, + nhoff + offsetof(struct gre_hdr, proto)); + + if (gre_flags & (GRE_VERSION|GRE_ROUTING)) + break; + + proto = gre_proto; + nhoff += 4; + if (gre_flags & GRE_CSUM) + nhoff += 4; + if (gre_flags & GRE_KEY) + nhoff += 4; + if (gre_flags & GRE_SEQ) + nhoff += 4; + + if (proto == ETH_P_8021Q) { + proto = load_half(skb, + nhoff + offsetof(struct vlan_hdr, + h_vlan_encapsulated_proto)); + nhoff += sizeof(struct vlan_hdr); + } + + if (proto == ETH_P_IP) + nhoff = parse_ip(skb, nhoff, &ip_proto, flow); + else if (proto == ETH_P_IPV6) + nhoff = parse_ipv6(skb, nhoff, &ip_proto, flow); + else + return false; + break; + } + case IPPROTO_IPIP: + nhoff = parse_ip(skb, nhoff, &ip_proto, flow); + break; + case IPPROTO_IPV6: + nhoff = parse_ipv6(skb, nhoff, &ip_proto, flow); + break; + default: + break; + } + + flow->ip_proto = ip_proto; + poff = proto_ports_offset(ip_proto); + if (poff >= 0) { + nhoff += poff; + flow->ports = load_word(skb, nhoff); + } + + flow->thoff = (__u16) nhoff; + + return true; +} + +struct bpf_map_def SEC("maps") hash_map = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(__be32), + .value_size = sizeof(long), + .max_entries = 1024, +}; + +SEC("socket2") +int bpf_prog2(struct sk_buff *skb) +{ + struct flow_keys flow; + long *value; + u32 key; + + if (!flow_dissector(skb, &flow)) + return 0; + + key = flow.dst; + value = bpf_map_lookup_elem(&hash_map, &key); + if (value) { + __sync_fetch_and_add(value, 1); + } else { + long val = 1; + + bpf_map_update_elem(&hash_map, &key, &val, BPF_ANY); + } + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/sockex2_user.c b/samples/bpf/sockex2_user.c new file mode 100644 index 00000000000..d2d5f5a790d --- /dev/null +++ b/samples/bpf/sockex2_user.c @@ -0,0 +1,44 @@ +#include <stdio.h> +#include <assert.h> +#include <linux/bpf.h> +#include "libbpf.h" +#include "bpf_load.h" +#include <unistd.h> +#include <arpa/inet.h> + +int main(int ac, char **argv) +{ + char filename[256]; + FILE *f; + int i, sock; + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + + if (load_bpf_file(filename)) { + printf("%s", bpf_log_buf); + return 1; + } + + sock = open_raw_sock("lo"); + + assert(setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, prog_fd, + sizeof(prog_fd[0])) == 0); + + f = popen("ping -c5 localhost", "r"); + (void) f; + + for (i = 0; i < 5; i++) { + int key = 0, next_key; + long long value; + + while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0) { + bpf_lookup_elem(map_fd[0], &next_key, &value); + printf("ip %s count %lld\n", + inet_ntoa((struct in_addr){htonl(next_key)}), + value); + key = next_key; + } + sleep(1); + } + return 0; +} |