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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 | // SPDX-License-Identifier: GPL-2.0 #include <stddef.h> #include <string.h> #include <netinet/in.h> #include <linux/bpf.h> #include <linux/if_ether.h> #include <linux/if_packet.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/tcp.h> #include <bpf/bpf_helpers.h> #include <bpf/bpf_endian.h> #include "bpf_tcp_helpers.h" #include "test_tcpbpf.h" struct tcpbpf_globals global = {}; /** * SOL_TCP is defined in <netinet/tcp.h> while * TCP_SAVED_SYN is defined in already included <linux/tcp.h> */ #ifndef SOL_TCP #define SOL_TCP 6 #endif static __always_inline int get_tp_window_clamp(struct bpf_sock_ops *skops) { struct bpf_sock *sk; struct tcp_sock *tp; sk = skops->sk; if (!sk) return -1; tp = bpf_skc_to_tcp_sock(sk); if (!tp) return -1; return tp->window_clamp; } SEC("sockops") int bpf_testcb(struct bpf_sock_ops *skops) { char header[sizeof(struct ipv6hdr) + sizeof(struct tcphdr)]; struct bpf_sock_ops *reuse = skops; struct tcphdr *thdr; int window_clamp = 9216; int save_syn = 1; int rv = -1; int v = 0; int op; /* Test reading fields in bpf_sock_ops using single register */ asm volatile ( "%[reuse] = *(u32 *)(%[reuse] +96)" : [reuse] "+r"(reuse) :); asm volatile ( "%[op] = *(u32 *)(%[skops] +96)" : [op] "+r"(op) : [skops] "r"(skops) :); asm volatile ( "r9 = %[skops];\n" "r8 = *(u32 *)(r9 +164);\n" "*(u32 *)(r9 +164) = r8;\n" :: [skops] "r"(skops) : "r9", "r8"); asm volatile ( "r1 = %[skops];\n" "r1 = *(u64 *)(r1 +184);\n" "if r1 == 0 goto +1;\n" "r1 = *(u32 *)(r1 +4);\n" :: [skops] "r"(skops):"r1"); asm volatile ( "r9 = %[skops];\n" "r9 = *(u64 *)(r9 +184);\n" "if r9 == 0 goto +1;\n" "r9 = *(u32 *)(r9 +4);\n" :: [skops] "r"(skops):"r9"); asm volatile ( "r1 = %[skops];\n" "r2 = *(u64 *)(r1 +184);\n" "if r2 == 0 goto +1;\n" "r2 = *(u32 *)(r2 +4);\n" :: [skops] "r"(skops):"r1", "r2"); op = (int) skops->op; global.event_map |= (1 << op); switch (op) { case BPF_SOCK_OPS_TCP_CONNECT_CB: rv = bpf_setsockopt(skops, SOL_TCP, TCP_WINDOW_CLAMP, &window_clamp, sizeof(window_clamp)); global.window_clamp_client = get_tp_window_clamp(skops); break; case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: /* Test failure to set largest cb flag (assumes not defined) */ global.bad_cb_test_rv = bpf_sock_ops_cb_flags_set(skops, 0x80); /* Set callback */ global.good_cb_test_rv = bpf_sock_ops_cb_flags_set(skops, BPF_SOCK_OPS_STATE_CB_FLAG); break; case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: skops->sk_txhash = 0x12345f; v = 0xff; rv = bpf_setsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v, sizeof(v)); if (skops->family == AF_INET6) { v = bpf_getsockopt(skops, IPPROTO_TCP, TCP_SAVED_SYN, header, (sizeof(struct ipv6hdr) + sizeof(struct tcphdr))); if (!v) { int offset = sizeof(struct ipv6hdr); thdr = (struct tcphdr *)(header + offset); v = thdr->syn; global.tcp_saved_syn = v; } } rv = bpf_setsockopt(skops, SOL_TCP, TCP_WINDOW_CLAMP, &window_clamp, sizeof(window_clamp)); global.window_clamp_server = get_tp_window_clamp(skops); break; case BPF_SOCK_OPS_RTO_CB: break; case BPF_SOCK_OPS_RETRANS_CB: break; case BPF_SOCK_OPS_STATE_CB: if (skops->args[1] == BPF_TCP_CLOSE) { if (skops->args[0] == BPF_TCP_LISTEN) { global.num_listen++; } else { global.total_retrans = skops->total_retrans; global.data_segs_in = skops->data_segs_in; global.data_segs_out = skops->data_segs_out; global.bytes_received = skops->bytes_received; global.bytes_acked = skops->bytes_acked; } global.num_close_events++; } break; case BPF_SOCK_OPS_TCP_LISTEN_CB: bpf_sock_ops_cb_flags_set(skops, BPF_SOCK_OPS_STATE_CB_FLAG); v = bpf_setsockopt(skops, IPPROTO_TCP, TCP_SAVE_SYN, &save_syn, sizeof(save_syn)); /* Update global map w/ result of setsock opt */ global.tcp_save_syn = v; break; default: rv = -1; } skops->reply = rv; return 1; } char _license[] SEC("license") = "GPL"; |