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1// SPDX-License-Identifier: GPL-2.02#include "bpf_tracing_net.h"3#include <bpf/bpf_helpers.h>4#include <bpf/bpf_endian.h>5#include "test_tcpbpf.h"6 7struct tcpbpf_globals global = {};8 9/**10 * SOL_TCP is defined in <netinet/tcp.h> while11 * TCP_SAVED_SYN is defined in already included <linux/tcp.h>12 */13#ifndef SOL_TCP14#define SOL_TCP 615#endif16 17static __always_inline int get_tp_window_clamp(struct bpf_sock_ops *skops)18{19 struct bpf_sock *sk;20 struct tcp_sock *tp;21 22 sk = skops->sk;23 if (!sk)24 return -1;25 tp = bpf_skc_to_tcp_sock(sk);26 if (!tp)27 return -1;28 return tp->window_clamp;29}30 31SEC("sockops")32int bpf_testcb(struct bpf_sock_ops *skops)33{34 char header[sizeof(struct ipv6hdr) + sizeof(struct tcphdr)];35 struct bpf_sock_ops *reuse = skops;36 struct tcphdr *thdr;37 int window_clamp = 9216;38 int save_syn = 1;39 int rv = -1;40 int v = 0;41 int op;42 43 /* Test reading fields in bpf_sock_ops using single register */44 asm volatile (45 "%[reuse] = *(u32 *)(%[reuse] +96)"46 : [reuse] "+r"(reuse)47 :);48 49 asm volatile (50 "%[op] = *(u32 *)(%[skops] +96)"51 : [op] "=r"(op)52 : [skops] "r"(skops)53 :);54 55 asm volatile (56 "r9 = %[skops];\n"57 "r8 = *(u32 *)(r9 +164);\n"58 "*(u32 *)(r9 +164) = r8;\n"59 :: [skops] "r"(skops)60 : "r9", "r8");61 62 asm volatile (63 "r1 = %[skops];\n"64 "r1 = *(u64 *)(r1 +184);\n"65 "if r1 == 0 goto +1;\n"66 "r1 = *(u32 *)(r1 +4);\n"67 :: [skops] "r"(skops):"r1");68 69 asm volatile (70 "r9 = %[skops];\n"71 "r9 = *(u64 *)(r9 +184);\n"72 "if r9 == 0 goto +1;\n"73 "r9 = *(u32 *)(r9 +4);\n"74 :: [skops] "r"(skops):"r9");75 76 asm volatile (77 "r1 = %[skops];\n"78 "r2 = *(u64 *)(r1 +184);\n"79 "if r2 == 0 goto +1;\n"80 "r2 = *(u32 *)(r2 +4);\n"81 :: [skops] "r"(skops):"r1", "r2");82 83 op = (int) skops->op;84 85 global.event_map |= (1 << op);86 87 switch (op) {88 case BPF_SOCK_OPS_TCP_CONNECT_CB:89 rv = bpf_setsockopt(skops, SOL_TCP, TCP_WINDOW_CLAMP,90 &window_clamp, sizeof(window_clamp));91 global.window_clamp_client = get_tp_window_clamp(skops);92 break;93 case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:94 /* Test failure to set largest cb flag (assumes not defined) */95 global.bad_cb_test_rv = bpf_sock_ops_cb_flags_set(skops, 0x80);96 /* Set callback */97 global.good_cb_test_rv = bpf_sock_ops_cb_flags_set(skops,98 BPF_SOCK_OPS_STATE_CB_FLAG);99 break;100 case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:101 skops->sk_txhash = 0x12345f;102 v = 0xff;103 rv = bpf_setsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v,104 sizeof(v));105 if (skops->family == AF_INET6) {106 v = bpf_getsockopt(skops, IPPROTO_TCP, TCP_SAVED_SYN,107 header, (sizeof(struct ipv6hdr) +108 sizeof(struct tcphdr)));109 if (!v) {110 int offset = sizeof(struct ipv6hdr);111 112 thdr = (struct tcphdr *)(header + offset);113 v = thdr->syn;114 115 global.tcp_saved_syn = v;116 }117 }118 rv = bpf_setsockopt(skops, SOL_TCP, TCP_WINDOW_CLAMP,119 &window_clamp, sizeof(window_clamp));120 121 global.window_clamp_server = get_tp_window_clamp(skops);122 break;123 case BPF_SOCK_OPS_RTO_CB:124 break;125 case BPF_SOCK_OPS_RETRANS_CB:126 break;127 case BPF_SOCK_OPS_STATE_CB:128 if (skops->args[1] == BPF_TCP_CLOSE) {129 if (skops->args[0] == BPF_TCP_LISTEN) {130 global.num_listen++;131 } else {132 global.total_retrans = skops->total_retrans;133 global.data_segs_in = skops->data_segs_in;134 global.data_segs_out = skops->data_segs_out;135 global.bytes_received = skops->bytes_received;136 global.bytes_acked = skops->bytes_acked;137 }138 global.num_close_events++;139 }140 break;141 case BPF_SOCK_OPS_TCP_LISTEN_CB:142 bpf_sock_ops_cb_flags_set(skops, BPF_SOCK_OPS_STATE_CB_FLAG);143 v = bpf_setsockopt(skops, IPPROTO_TCP, TCP_SAVE_SYN,144 &save_syn, sizeof(save_syn));145 /* Update global map w/ result of setsock opt */146 global.tcp_save_syn = v;147 break;148 default:149 rv = -1;150 }151 skops->reply = rv;152 return 1;153}154char _license[] SEC("license") = "GPL";155