tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2020 Facebook */
   3 #include "bpf_iter.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_tcp_sock(struct seq_file *seq, struct tcp_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 inet_sock *inet;
  80         unsigned long timer_expires;
  81         const struct sock *sp;
  82         __u16 destp, srcp;
  83         __be32 dest, src;
  84         int timer_active;
  85         int rx_queue;
  86         int state;
  87
  88         icsk = &tp->inet_conn;
  89         inet = &icsk->icsk_inet;
  90         sp = &inet->sk;
  91         fastopenq = &icsk->icsk_accept_queue.fastopenq;
  92
  93         dest = inet->inet_daddr;
  94         src = inet->inet_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->rcv_nxt - tp->copied_seq;
 119                 if (rx_queue < 0)
 120                         rx_queue = 0;
 121         }
 122
 123         BPF_SEQ_PRINTF(seq, "%4d: %08X:%04X %08X:%04X ",
 124                        seq_num, src, srcp, dest, destp);
 125         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d ",
 126                        state,
 127                        tp->write_seq - tp->snd_una, rx_queue,
 128                        timer_active,
 129                        jiffies_delta_to_clock_t(timer_expires - bpf_jiffies64()),
 130                        icsk->icsk_retransmits, uid,
 131                        icsk->icsk_probes_out,
 132                        sock_i_ino(sp),
 133                        sp->sk_refcnt.refs.counter);
 134         BPF_SEQ_PRINTF(seq, "%pK %lu %lu %u %u %d\n",
 135                        tp,
 136                        jiffies_to_clock_t(icsk->icsk_rto),
 137                        jiffies_to_clock_t(icsk->icsk_ack.ato),
 138                        (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(icsk),
 139                        tp->snd_cwnd,
 140                        state == TCP_LISTEN ? fastopenq->max_qlen
 141                                 : (tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh)
 142                       );
 143
 144         return 0;
 145 }
 146
 147 static int dump_tw_sock(struct seq_file *seq, struct tcp_timewait_sock *ttw,
 148                         uid_t uid, __u32 seq_num)
 149 {
 150         struct inet_timewait_sock *tw = &ttw->tw_sk;
 151         __u16 destp, srcp;
 152         __be32 dest, src;
 153         long delta;
 154
 155         delta = tw->tw_timer.expires - bpf_jiffies64();
 156         dest = tw->tw_daddr;
 157         src  = tw->tw_rcv_saddr;
 158         destp = bpf_ntohs(tw->tw_dport);
 159         srcp  = bpf_ntohs(tw->tw_sport);
 160
 161         BPF_SEQ_PRINTF(seq, "%4d: %08X:%04X %08X:%04X ",
 162                        seq_num, src, srcp, dest, destp);
 163
 164         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
 165                        tw->tw_substate, 0, 0,
 166                        3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
 167                        tw->tw_refcnt.refs.counter, tw);
 168
 169         return 0;
 170 }
 171
 172 static int dump_req_sock(struct seq_file *seq, struct tcp_request_sock *treq,
 173                          uid_t uid, __u32 seq_num)
 174 {
 175         struct inet_request_sock *irsk = &treq->req;
 176         struct request_sock *req = &irsk->req;
 177         long ttd;
 178
 179         ttd = req->rsk_timer.expires - bpf_jiffies64();
 180
 181         if (ttd < 0)
 182                 ttd = 0;
 183
 184         BPF_SEQ_PRINTF(seq, "%4d: %08X:%04X %08X:%04X ",
 185                        seq_num, irsk->ir_loc_addr,
 186                        irsk->ir_num, irsk->ir_rmt_addr,
 187                        bpf_ntohs(irsk->ir_rmt_port));
 188         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
 189                        TCP_SYN_RECV, 0, 0, 1, jiffies_to_clock_t(ttd),
 190                        req->num_timeout, uid, 0, 0, 0, req);
 191
 192         return 0;
 193 }
 194
 195 SEC("iter/tcp")
 196 int dump_tcp4(struct bpf_iter__tcp *ctx)
 197 {
 198         struct sock_common *sk_common = ctx->sk_common;
 199         struct seq_file *seq = ctx->meta->seq;
 200         struct tcp_timewait_sock *tw;
 201         struct tcp_request_sock *req;
 202         struct tcp_sock *tp;
 203         uid_t uid = ctx->uid;
 204         __u32 seq_num;
 205
 206         if (sk_common == (void *)0)
 207                 return 0;
 208
 209         seq_num = ctx->meta->seq_num;
 210         if (seq_num == 0)
 211                 BPF_SEQ_PRINTF(seq, "  sl  "
 212                                     "local_address "
 213                                     "rem_address   "
 214                                     "st tx_queue rx_queue tr tm->when retrnsmt"
 215                                     "   uid  timeout inode\n");
 216
 217         if (sk_common->skc_family != AF_INET)
 218                 return 0;
 219
 220         tp = bpf_skc_to_tcp_sock(sk_common);
 221         if (tp)
 222                 return dump_tcp_sock(seq, tp, uid, seq_num);
 223
 224         tw = bpf_skc_to_tcp_timewait_sock(sk_common);
 225         if (tw)
 226                 return dump_tw_sock(seq, tw, uid, seq_num);
 227
 228         req = bpf_skc_to_tcp_request_sock(sk_common);
 229         if (req)
 230                 return dump_req_sock(seq, req, uid, seq_num);
 231
 232         return 0;
 233 }