1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 #include <vmlinux.h> 4 #include "bpf_tracing_net.h" 5 #include <bpf/bpf_helpers.h> 6 #include <bpf/bpf_endian.h> 7 8 char _license[] SEC("license") = "GPL"; 9 10 static int hlist_unhashed_lockless(const struct hlist_node *h) 11 { 12 return !(h->pprev); 13 } 14 15 static int timer_pending(const struct timer_list * timer) 16 { 17 return !hlist_unhashed_lockless(&timer->entry); 18 } 19 20 extern unsigned CONFIG_HZ __kconfig; 21 22 #define USER_HZ 100 23 #define NSEC_PER_SEC 1000000000ULL 24 static clock_t jiffies_to_clock_t(unsigned long x) 25 { 26 /* The implementation here tailored to a particular 27 * setting of USER_HZ. 28 */ 29 u64 tick_nsec = (NSEC_PER_SEC + CONFIG_HZ/2) / CONFIG_HZ; 30 u64 user_hz_nsec = NSEC_PER_SEC / USER_HZ; 31 32 if ((tick_nsec % user_hz_nsec) == 0) { 33 if (CONFIG_HZ < USER_HZ) 34 return x * (USER_HZ / CONFIG_HZ); 35 else 36 return x / (CONFIG_HZ / USER_HZ); 37 } 38 return x * tick_nsec/user_hz_nsec; 39 } 40 41 static clock_t jiffies_delta_to_clock_t(long delta) 42 { 43 if (delta <= 0) 44 return 0; 45 46 return jiffies_to_clock_t(delta); 47 } 48 49 static long sock_i_ino(const struct sock *sk) 50 { 51 const struct socket *sk_socket = sk->sk_socket; 52 const struct inode *inode; 53 unsigned long ino; 54 55 if (!sk_socket) 56 return 0; 57 58 inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; 59 bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino); 60 return ino; 61 } 62 63 static bool 64 inet_csk_in_pingpong_mode(const struct inet_connection_sock *icsk) 65 { 66 return icsk->icsk_ack.pingpong >= TCP_PINGPONG_THRESH; 67 } 68 69 static bool tcp_in_initial_slowstart(const struct tcp_sock *tcp) 70 { 71 return tcp->snd_ssthresh >= TCP_INFINITE_SSTHRESH; 72 } 73 74 static int dump_tcp6_sock(struct seq_file *seq, struct tcp6_sock *tp, 75 uid_t uid, __u32 seq_num) 76 { 77 const struct inet_connection_sock *icsk; 78 const struct fastopen_queue *fastopenq; 79 const struct in6_addr *dest, *src; 80 const struct inet_sock *inet; 81 unsigned long timer_expires; 82 const struct sock *sp; 83 __u16 destp, srcp; 84 int timer_active; 85 int rx_queue; 86 int state; 87 88 icsk = &tp->tcp.inet_conn; 89 inet = &icsk->icsk_inet; 90 sp = &inet->sk; 91 fastopenq = &icsk->icsk_accept_queue.fastopenq; 92 93 dest = &sp->sk_v6_daddr; 94 src = &sp->sk_v6_rcv_saddr; 95 destp = bpf_ntohs(inet->inet_dport); 96 srcp = bpf_ntohs(inet->inet_sport); 97 98 if (icsk->icsk_pending == ICSK_TIME_RETRANS || 99 icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT || 100 icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) { 101 timer_active = 1; 102 timer_expires = icsk->icsk_timeout; 103 } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { 104 timer_active = 4; 105 timer_expires = icsk->icsk_timeout; 106 } else if (timer_pending(&sp->sk_timer)) { 107 timer_active = 2; 108 timer_expires = sp->sk_timer.expires; 109 } else { 110 timer_active = 0; 111 timer_expires = bpf_jiffies64(); 112 } 113 114 state = sp->sk_state; 115 if (state == TCP_LISTEN) { 116 rx_queue = sp->sk_ack_backlog; 117 } else { 118 rx_queue = tp->tcp.rcv_nxt - tp->tcp.copied_seq; 119 if (rx_queue < 0) 120 rx_queue = 0; 121 } 122 123 BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ", 124 seq_num, 125 src->s6_addr32[0], src->s6_addr32[1], 126 src->s6_addr32[2], src->s6_addr32[3], srcp, 127 dest->s6_addr32[0], dest->s6_addr32[1], 128 dest->s6_addr32[2], dest->s6_addr32[3], destp); 129 BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d ", 130 state, 131 tp->tcp.write_seq - tp->tcp.snd_una, rx_queue, 132 timer_active, 133 jiffies_delta_to_clock_t(timer_expires - bpf_jiffies64()), 134 icsk->icsk_retransmits, uid, 135 icsk->icsk_probes_out, 136 sock_i_ino(sp), 137 sp->sk_refcnt.refs.counter); 138 BPF_SEQ_PRINTF(seq, "%pK %lu %lu %u %u %d\n", 139 tp, 140 jiffies_to_clock_t(icsk->icsk_rto), 141 jiffies_to_clock_t(icsk->icsk_ack.ato), 142 (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(icsk), 143 tp->tcp.snd_cwnd, 144 state == TCP_LISTEN ? fastopenq->max_qlen 145 : (tcp_in_initial_slowstart(&tp->tcp) ? -1 146 : tp->tcp.snd_ssthresh) 147 ); 148 149 return 0; 150 } 151 152 static int dump_tw_sock(struct seq_file *seq, struct tcp_timewait_sock *ttw, 153 uid_t uid, __u32 seq_num) 154 { 155 struct inet_timewait_sock *tw = &ttw->tw_sk; 156 const struct in6_addr *dest, *src; 157 __u16 destp, srcp; 158 long delta; 159 160 delta = tw->tw_timer.expires - bpf_jiffies64(); 161 dest = &tw->tw_v6_daddr; 162 src = &tw->tw_v6_rcv_saddr; 163 destp = bpf_ntohs(tw->tw_dport); 164 srcp = bpf_ntohs(tw->tw_sport); 165 166 BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ", 167 seq_num, 168 src->s6_addr32[0], src->s6_addr32[1], 169 src->s6_addr32[2], src->s6_addr32[3], srcp, 170 dest->s6_addr32[0], dest->s6_addr32[1], 171 dest->s6_addr32[2], dest->s6_addr32[3], destp); 172 173 BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 174 tw->tw_substate, 0, 0, 175 3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0, 176 tw->tw_refcnt.refs.counter, tw); 177 178 return 0; 179 } 180 181 static int dump_req_sock(struct seq_file *seq, struct tcp_request_sock *treq, 182 uid_t uid, __u32 seq_num) 183 { 184 struct inet_request_sock *irsk = &treq->req; 185 struct request_sock *req = &irsk->req; 186 struct in6_addr *src, *dest; 187 long ttd; 188 189 ttd = req->rsk_timer.expires - bpf_jiffies64(); 190 src = &irsk->ir_v6_loc_addr; 191 dest = &irsk->ir_v6_rmt_addr; 192 193 if (ttd < 0) 194 ttd = 0; 195 196 BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ", 197 seq_num, 198 src->s6_addr32[0], src->s6_addr32[1], 199 src->s6_addr32[2], src->s6_addr32[3], 200 irsk->ir_num, 201 dest->s6_addr32[0], dest->s6_addr32[1], 202 dest->s6_addr32[2], dest->s6_addr32[3], 203 bpf_ntohs(irsk->ir_rmt_port)); 204 BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n", 205 TCP_SYN_RECV, 0, 0, 1, jiffies_to_clock_t(ttd), 206 req->num_timeout, uid, 0, 0, 0, req); 207 208 return 0; 209 } 210 211 SEC("iter/tcp") 212 int dump_tcp6(struct bpf_iter__tcp *ctx) 213 { 214 struct sock_common *sk_common = ctx->sk_common; 215 struct seq_file *seq = ctx->meta->seq; 216 struct tcp_timewait_sock *tw; 217 struct tcp_request_sock *req; 218 struct tcp6_sock *tp; 219 uid_t uid = ctx->uid; 220 __u32 seq_num; 221 222 if (sk_common == (void *)0) 223 return 0; 224 225 seq_num = ctx->meta->seq_num; 226 if (seq_num == 0) 227 BPF_SEQ_PRINTF(seq, " sl " 228 "local_address " 229 "remote_address " 230 "st tx_queue rx_queue tr tm->when retrnsmt" 231 " uid timeout inode\n"); 232 233 if (sk_common->skc_family != AF_INET6) 234 return 0; 235 236 tp = bpf_skc_to_tcp6_sock(sk_common); 237 if (tp) 238 return dump_tcp6_sock(seq, tp, uid, seq_num); 239 240 tw = bpf_skc_to_tcp_timewait_sock(sk_common); 241 if (tw) 242 return dump_tw_sock(seq, tw, uid, seq_num); 243 244 req = bpf_skc_to_tcp_request_sock(sk_common); 245 if (req) 246 return dump_req_sock(seq, req, uid, seq_num); 247 248 return 0; 249 } 250