diff options
Diffstat (limited to 'tools/testing/selftests/bpf/test_tcp_estats.c')
| -rw-r--r-- | tools/testing/selftests/bpf/test_tcp_estats.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/test_tcp_estats.c b/tools/testing/selftests/bpf/test_tcp_estats.c new file mode 100644 index 000000000..bee3bbecc --- /dev/null +++ b/tools/testing/selftests/bpf/test_tcp_estats.c @@ -0,0 +1,258 @@ +/* Copyright (c) 2017 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ + +/* This program shows clang/llvm is able to generate code pattern + * like: + * _tcp_send_active_reset: + * 0: bf 16 00 00 00 00 00 00 r6 = r1 + * ...... + * 335: b7 01 00 00 0f 00 00 00 r1 = 15 + * 336: 05 00 48 00 00 00 00 00 goto 72 + * + * LBB0_3: + * 337: b7 01 00 00 01 00 00 00 r1 = 1 + * 338: 63 1a d0 ff 00 00 00 00 *(u32 *)(r10 - 48) = r1 + * 408: b7 01 00 00 03 00 00 00 r1 = 3 + * + * LBB0_4: + * 409: 71 a2 fe ff 00 00 00 00 r2 = *(u8 *)(r10 - 2) + * 410: bf a7 00 00 00 00 00 00 r7 = r10 + * 411: 07 07 00 00 b8 ff ff ff r7 += -72 + * 412: bf 73 00 00 00 00 00 00 r3 = r7 + * 413: 0f 13 00 00 00 00 00 00 r3 += r1 + * 414: 73 23 2d 00 00 00 00 00 *(u8 *)(r3 + 45) = r2 + * + * From the above code snippet, the code generated by the compiler + * is reasonable. The "r1" is assigned to different values in basic + * blocks "_tcp_send_active_reset" and "LBB0_3", and used in "LBB0_4". + * The verifier should be able to handle such code patterns. + */ +#include <string.h> +#include <linux/bpf.h> +#include <linux/ipv6.h> +#include <linux/version.h> +#include <sys/socket.h> +#include "bpf_helpers.h" + +#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;}) +#define TCP_ESTATS_MAGIC 0xBAADBEEF + +/* This test case needs "sock" and "pt_regs" data structure. + * Recursively, "sock" needs "sock_common" and "inet_sock". + * However, this is a unit test case only for + * verifier purpose without bpf program execution. + * We can safely mock much simpler data structures, basically + * only taking the necessary fields from kernel headers. + */ +typedef __u32 __bitwise __portpair; +typedef __u64 __bitwise __addrpair; + +struct sock_common { + unsigned short skc_family; + union { + __addrpair skc_addrpair; + struct { + __be32 skc_daddr; + __be32 skc_rcv_saddr; + }; + }; + union { + __portpair skc_portpair; + struct { + __be16 skc_dport; + __u16 skc_num; + }; + }; + struct in6_addr skc_v6_daddr; + struct in6_addr skc_v6_rcv_saddr; +}; + +struct sock { + struct sock_common __sk_common; +#define sk_family __sk_common.skc_family +#define sk_v6_daddr __sk_common.skc_v6_daddr +#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr +}; + +struct inet_sock { + struct sock sk; +#define inet_daddr sk.__sk_common.skc_daddr +#define inet_dport sk.__sk_common.skc_dport + __be32 inet_saddr; + __be16 inet_sport; +}; + +struct pt_regs { + long di; +}; + +static inline struct inet_sock *inet_sk(const struct sock *sk) +{ + return (struct inet_sock *)sk; +} + +/* Define various data structures for state recording. + * Some fields are not used due to test simplification. + */ +enum tcp_estats_addrtype { + TCP_ESTATS_ADDRTYPE_IPV4 = 1, + TCP_ESTATS_ADDRTYPE_IPV6 = 2 +}; + +enum tcp_estats_event_type { + TCP_ESTATS_ESTABLISH, + TCP_ESTATS_PERIODIC, + TCP_ESTATS_TIMEOUT, + TCP_ESTATS_RETRANSMIT_TIMEOUT, + TCP_ESTATS_RETRANSMIT_OTHER, + TCP_ESTATS_SYN_RETRANSMIT, + TCP_ESTATS_SYNACK_RETRANSMIT, + TCP_ESTATS_TERM, + TCP_ESTATS_TX_RESET, + TCP_ESTATS_RX_RESET, + TCP_ESTATS_WRITE_TIMEOUT, + TCP_ESTATS_CONN_TIMEOUT, + TCP_ESTATS_ACK_LATENCY, + TCP_ESTATS_NEVENTS, +}; + +struct tcp_estats_event { + int pid; + int cpu; + unsigned long ts; + unsigned int magic; + enum tcp_estats_event_type event_type; +}; + +/* The below data structure is packed in order for + * llvm compiler to generate expected code. + */ +struct tcp_estats_conn_id { + unsigned int localaddressType; + struct { + unsigned char data[16]; + } localaddress; + struct { + unsigned char data[16]; + } remaddress; + unsigned short localport; + unsigned short remport; +} __attribute__((__packed__)); + +struct tcp_estats_basic_event { + struct tcp_estats_event event; + struct tcp_estats_conn_id conn_id; +}; + +struct bpf_map_def SEC("maps") ev_record_map = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(__u32), + .value_size = sizeof(struct tcp_estats_basic_event), + .max_entries = 1024, +}; + +struct dummy_tracepoint_args { + unsigned long long pad; + struct sock *sock; +}; + +static __always_inline void tcp_estats_ev_init(struct tcp_estats_event *event, + enum tcp_estats_event_type type) +{ + event->magic = TCP_ESTATS_MAGIC; + event->ts = bpf_ktime_get_ns(); + event->event_type = type; +} + +static __always_inline void unaligned_u32_set(unsigned char *to, __u8 *from) +{ + to[0] = _(from[0]); + to[1] = _(from[1]); + to[2] = _(from[2]); + to[3] = _(from[3]); +} + +static __always_inline void conn_id_ipv4_init(struct tcp_estats_conn_id *conn_id, + __be32 *saddr, __be32 *daddr) +{ + conn_id->localaddressType = TCP_ESTATS_ADDRTYPE_IPV4; + + unaligned_u32_set(conn_id->localaddress.data, (__u8 *)saddr); + unaligned_u32_set(conn_id->remaddress.data, (__u8 *)daddr); +} + +static __always_inline void conn_id_ipv6_init(struct tcp_estats_conn_id *conn_id, + __be32 *saddr, __be32 *daddr) +{ + conn_id->localaddressType = TCP_ESTATS_ADDRTYPE_IPV6; + + unaligned_u32_set(conn_id->localaddress.data, (__u8 *)saddr); + unaligned_u32_set(conn_id->localaddress.data + sizeof(__u32), + (__u8 *)(saddr + 1)); + unaligned_u32_set(conn_id->localaddress.data + sizeof(__u32) * 2, + (__u8 *)(saddr + 2)); + unaligned_u32_set(conn_id->localaddress.data + sizeof(__u32) * 3, + (__u8 *)(saddr + 3)); + + unaligned_u32_set(conn_id->remaddress.data, + (__u8 *)(daddr)); + unaligned_u32_set(conn_id->remaddress.data + sizeof(__u32), + (__u8 *)(daddr + 1)); + unaligned_u32_set(conn_id->remaddress.data + sizeof(__u32) * 2, + (__u8 *)(daddr + 2)); + unaligned_u32_set(conn_id->remaddress.data + sizeof(__u32) * 3, + (__u8 *)(daddr + 3)); +} + +static __always_inline void tcp_estats_conn_id_init(struct tcp_estats_conn_id *conn_id, + struct sock *sk) +{ + conn_id->localport = _(inet_sk(sk)->inet_sport); + conn_id->remport = _(inet_sk(sk)->inet_dport); + + if (_(sk->sk_family) == AF_INET6) + conn_id_ipv6_init(conn_id, + sk->sk_v6_rcv_saddr.s6_addr32, + sk->sk_v6_daddr.s6_addr32); + else + conn_id_ipv4_init(conn_id, + &inet_sk(sk)->inet_saddr, + &inet_sk(sk)->inet_daddr); +} + +static __always_inline void tcp_estats_init(struct sock *sk, + struct tcp_estats_event *event, + struct tcp_estats_conn_id *conn_id, + enum tcp_estats_event_type type) +{ + tcp_estats_ev_init(event, type); + tcp_estats_conn_id_init(conn_id, sk); +} + +static __always_inline void send_basic_event(struct sock *sk, + enum tcp_estats_event_type type) +{ + struct tcp_estats_basic_event ev; + __u32 key = bpf_get_prandom_u32(); + + memset(&ev, 0, sizeof(ev)); + tcp_estats_init(sk, &ev.event, &ev.conn_id, type); + bpf_map_update_elem(&ev_record_map, &key, &ev, BPF_ANY); +} + +SEC("dummy_tracepoint") +int _dummy_tracepoint(struct dummy_tracepoint_args *arg) +{ + if (!arg->sock) + return 0; + + send_basic_event(arg->sock, TCP_ESTATS_TX_RESET); + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1; /* ignored by tracepoints, required by libbpf.a */ |