From: Alexei Starovoitov Date: Fri, 13 Mar 2015 18:57:43 +0000 (-0700) Subject: samples: bpf: add skb->field examples and tests X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=614cd3bd3758a806cea497d493b584e6157561f7;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git samples: bpf: add skb->field examples and tests - modify sockex1 example to count number of bytes in outgoing packets - modify sockex2 example to count number of bytes and packets per flow - add 4 stress tests that exercise 'skb->field' code path of verifier Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller --- diff --git a/samples/bpf/sockex1_kern.c b/samples/bpf/sockex1_kern.c index 066892662915..ed18e9a4909c 100644 --- a/samples/bpf/sockex1_kern.c +++ b/samples/bpf/sockex1_kern.c @@ -1,5 +1,6 @@ #include #include +#include #include #include "bpf_helpers.h" @@ -11,14 +12,17 @@ struct bpf_map_def SEC("maps") my_map = { }; SEC("socket1") -int bpf_prog1(struct sk_buff *skb) +int bpf_prog1(struct __sk_buff *skb) { int index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)); long *value; + if (skb->pkt_type != PACKET_OUTGOING) + return 0; + value = bpf_map_lookup_elem(&my_map, &index); if (value) - __sync_fetch_and_add(value, 1); + __sync_fetch_and_add(value, skb->len); return 0; } diff --git a/samples/bpf/sockex1_user.c b/samples/bpf/sockex1_user.c index 34a443ff3831..678ce4693551 100644 --- a/samples/bpf/sockex1_user.c +++ b/samples/bpf/sockex1_user.c @@ -40,7 +40,7 @@ int main(int ac, char **argv) key = IPPROTO_ICMP; assert(bpf_lookup_elem(map_fd[0], &key, &icmp_cnt) == 0); - printf("TCP %lld UDP %lld ICMP %lld packets\n", + printf("TCP %lld UDP %lld ICMP %lld bytes\n", tcp_cnt, udp_cnt, icmp_cnt); sleep(1); } diff --git a/samples/bpf/sockex2_kern.c b/samples/bpf/sockex2_kern.c index 6f0135f0f217..ba0e177ff561 100644 --- a/samples/bpf/sockex2_kern.c +++ b/samples/bpf/sockex2_kern.c @@ -42,13 +42,13 @@ static inline int proto_ports_offset(__u64 proto) } } -static inline int ip_is_fragment(struct sk_buff *ctx, __u64 nhoff) +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) +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); @@ -58,7 +58,7 @@ static inline __u32 ipv6_addr_hash(struct sk_buff *ctx, __u64 off) return (__u32)(w0 ^ w1 ^ w2 ^ w3); } -static inline __u64 parse_ip(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto, +static inline __u64 parse_ip(struct __sk_buff *skb, __u64 nhoff, __u64 *ip_proto, struct flow_keys *flow) { __u64 verlen; @@ -82,7 +82,7 @@ static inline __u64 parse_ip(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto, return nhoff; } -static inline __u64 parse_ipv6(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto, +static inline __u64 parse_ipv6(struct __sk_buff *skb, __u64 nhoff, __u64 *ip_proto, struct flow_keys *flow) { *ip_proto = load_byte(skb, @@ -96,7 +96,7 @@ static inline __u64 parse_ipv6(struct sk_buff *skb, __u64 nhoff, __u64 *ip_proto return nhoff; } -static inline bool flow_dissector(struct sk_buff *skb, struct flow_keys *flow) +static inline bool flow_dissector(struct __sk_buff *skb, struct flow_keys *flow) { __u64 nhoff = ETH_HLEN; __u64 ip_proto; @@ -183,18 +183,23 @@ static inline bool flow_dissector(struct sk_buff *skb, struct flow_keys *flow) return true; } +struct pair { + long packets; + long bytes; +}; + struct bpf_map_def SEC("maps") hash_map = { .type = BPF_MAP_TYPE_HASH, .key_size = sizeof(__be32), - .value_size = sizeof(long), + .value_size = sizeof(struct pair), .max_entries = 1024, }; SEC("socket2") -int bpf_prog2(struct sk_buff *skb) +int bpf_prog2(struct __sk_buff *skb) { struct flow_keys flow; - long *value; + struct pair *value; u32 key; if (!flow_dissector(skb, &flow)) @@ -203,9 +208,10 @@ int bpf_prog2(struct sk_buff *skb) key = flow.dst; value = bpf_map_lookup_elem(&hash_map, &key); if (value) { - __sync_fetch_and_add(value, 1); + __sync_fetch_and_add(&value->packets, 1); + __sync_fetch_and_add(&value->bytes, skb->len); } else { - long val = 1; + struct pair val = {1, skb->len}; bpf_map_update_elem(&hash_map, &key, &val, BPF_ANY); } diff --git a/samples/bpf/sockex2_user.c b/samples/bpf/sockex2_user.c index d2d5f5a790d3..29a276d766fc 100644 --- a/samples/bpf/sockex2_user.c +++ b/samples/bpf/sockex2_user.c @@ -6,6 +6,11 @@ #include #include +struct pair { + __u64 packets; + __u64 bytes; +}; + int main(int ac, char **argv) { char filename[256]; @@ -29,13 +34,13 @@ int main(int ac, char **argv) for (i = 0; i < 5; i++) { int key = 0, next_key; - long long value; + struct pair 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", + printf("ip %s bytes %lld packets %lld\n", inet_ntoa((struct in_addr){htonl(next_key)}), - value); + value.bytes, value.packets); key = next_key; } sleep(1); diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c index 7b56b59fad8e..df6dbb6576f6 100644 --- a/samples/bpf/test_verifier.c +++ b/samples/bpf/test_verifier.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "libbpf.h" #define MAX_INSNS 512 @@ -642,6 +643,75 @@ static struct bpf_test tests[] = { }, .result = ACCEPT, }, + { + "access skb fields ok", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, len)), + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, mark)), + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, pkt_type)), + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, queue_mapping)), + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 0), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + }, + { + "access skb fields bad1", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, -4), + BPF_EXIT_INSN(), + }, + .errstr = "invalid bpf_context access", + .result = REJECT, + }, + { + "access skb fields bad2", + .insns = { + BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 9), + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, pkt_type)), + BPF_EXIT_INSN(), + }, + .fixup = {4}, + .errstr = "different pointers", + .result = REJECT, + }, + { + "access skb fields bad3", + .insns = { + BPF_JMP_IMM(BPF_JGE, BPF_REG_1, 0, 2), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, + offsetof(struct __sk_buff, pkt_type)), + BPF_EXIT_INSN(), + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_LD_MAP_FD(BPF_REG_1, 0), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem), + BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1), + BPF_EXIT_INSN(), + BPF_MOV64_REG(BPF_REG_1, BPF_REG_0), + BPF_JMP_IMM(BPF_JA, 0, 0, -12), + }, + .fixup = {6}, + .errstr = "different pointers", + .result = REJECT, + }, }; static int probe_filter_length(struct bpf_insn *fp)