tools/testing/selftests/bpf/progs/bpf_iter_tcp6.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_tracing.h>
   7 #include <bpf/bpf_endian.h>
   8
   9 char _license[] SEC("license") = "GPL";
  10
  11 static int hlist_unhashed_lockless(const struct hlist_node *h)
  12 {
  13         return !(h->pprev);
  14 }
  15
  16 static int timer_pending(const struct timer_list * timer)
  17 {
  18         return !hlist_unhashed_lockless(&timer->entry);
  19 }
  20
  21 extern unsigned CONFIG_HZ __kconfig;
  22
  23 #define USER_HZ         100
  24 #define NSEC_PER_SEC    1000000000ULL
  25 static clock_t jiffies_to_clock_t(unsigned long x)
  26 {
  27         /* The implementation here tailored to a particular
  28          * setting of USER_HZ.
  29          */
  30         u64 tick_nsec = (NSEC_PER_SEC + CONFIG_HZ/2) / CONFIG_HZ;
  31         u64 user_hz_nsec = NSEC_PER_SEC / USER_HZ;
  32
  33         if ((tick_nsec % user_hz_nsec) == 0) {
  34                 if (CONFIG_HZ < USER_HZ)
  35                         return x * (USER_HZ / CONFIG_HZ);
  36                 else
  37                         return x / (CONFIG_HZ / USER_HZ);
  38         }
  39         return x * tick_nsec/user_hz_nsec;
  40 }
  41
  42 static clock_t jiffies_delta_to_clock_t(long delta)
  43 {
  44         if (delta <= 0)
  45                 return 0;
  46
  47         return jiffies_to_clock_t(delta);
  48 }
  49
  50 static long sock_i_ino(const struct sock *sk)
  51 {
  52         const struct socket *sk_socket = sk->sk_socket;
  53         const struct inode *inode;
  54         unsigned long ino;
  55
  56         if (!sk_socket)
  57                 return 0;
  58
  59         inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
  60         bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
  61         return ino;
  62 }
  63
  64 static bool
  65 inet_csk_in_pingpong_mode(const struct inet_connection_sock *icsk)
  66 {
  67         return icsk->icsk_ack.pingpong >= TCP_PINGPONG_THRESH;
  68 }
  69
  70 static bool tcp_in_initial_slowstart(const struct tcp_sock *tcp)
  71 {
  72         return tcp->snd_ssthresh >= TCP_INFINITE_SSTHRESH;
  73 }
  74
  75 static int dump_tcp6_sock(struct seq_file *seq, struct tcp6_sock *tp,
  76                          uid_t uid, __u32 seq_num)
  77 {
  78         const struct inet_connection_sock *icsk;
  79         const struct fastopen_queue *fastopenq;
  80         const struct in6_addr *dest, *src;
  81         const struct inet_sock *inet;
  82         unsigned long timer_expires;
  83         const struct sock *sp;
  84         __u16 destp, srcp;
  85         int timer_active;
  86         int rx_queue;
  87         int state;
  88
  89         icsk = &tp->tcp.inet_conn;
  90         inet = &icsk->icsk_inet;
  91         sp = &inet->sk;
  92         fastopenq = &icsk->icsk_accept_queue.fastopenq;
  93
  94         dest = &sp->sk_v6_daddr;
  95         src = &sp->sk_v6_rcv_saddr;
  96         destp = bpf_ntohs(inet->inet_dport);
  97         srcp = bpf_ntohs(inet->inet_sport);
  98
  99         if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
 100             icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
 101             icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
 102                 timer_active = 1;
 103                 timer_expires = icsk->icsk_timeout;
 104         } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
 105                 timer_active = 4;
 106                 timer_expires = icsk->icsk_timeout;
 107         } else if (timer_pending(&sp->sk_timer)) {
 108                 timer_active = 2;
 109                 timer_expires = sp->sk_timer.expires;
 110         } else {
 111                 timer_active = 0;
 112                 timer_expires = bpf_jiffies64();
 113         }
 114
 115         state = sp->sk_state;
 116         if (state == TCP_LISTEN) {
 117                 rx_queue = sp->sk_ack_backlog;
 118         } else {
 119                 rx_queue = tp->tcp.rcv_nxt - tp->tcp.copied_seq;
 120                 if (rx_queue < 0)
 121                         rx_queue = 0;
 122         }
 123
 124         BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ",
 125                        seq_num,
 126                        src->s6_addr32[0], src->s6_addr32[1],
 127                        src->s6_addr32[2], src->s6_addr32[3], srcp,
 128                        dest->s6_addr32[0], dest->s6_addr32[1],
 129                        dest->s6_addr32[2], dest->s6_addr32[3], destp);
 130         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d ",
 131                        state,
 132                        tp->tcp.write_seq - tp->tcp.snd_una, rx_queue,
 133                        timer_active,
 134                        jiffies_delta_to_clock_t(timer_expires - bpf_jiffies64()),
 135                        icsk->icsk_retransmits, uid,
 136                        icsk->icsk_probes_out,
 137                        sock_i_ino(sp),
 138                        sp->sk_refcnt.refs.counter);
 139         BPF_SEQ_PRINTF(seq, "%pK %lu %lu %u %u %d\n",
 140                        tp,
 141                        jiffies_to_clock_t(icsk->icsk_rto),
 142                        jiffies_to_clock_t(icsk->icsk_ack.ato),
 143                        (icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(icsk),
 144                        tp->tcp.snd_cwnd,
 145                        state == TCP_LISTEN ? fastopenq->max_qlen
 146                                 : (tcp_in_initial_slowstart(&tp->tcp) ? -1
 147                                                                       : tp->tcp.snd_ssthresh)
 148                       );
 149
 150         return 0;
 151 }
 152
 153 static int dump_tw_sock(struct seq_file *seq, struct tcp_timewait_sock *ttw,
 154                         uid_t uid, __u32 seq_num)
 155 {
 156         struct inet_timewait_sock *tw = &ttw->tw_sk;
 157         const struct in6_addr *dest, *src;
 158         __u16 destp, srcp;
 159         long delta;
 160
 161         delta = tw->tw_timer.expires - bpf_jiffies64();
 162         dest = &tw->tw_v6_daddr;
 163         src  = &tw->tw_v6_rcv_saddr;
 164         destp = bpf_ntohs(tw->tw_dport);
 165         srcp  = bpf_ntohs(tw->tw_sport);
 166
 167         BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ",
 168                        seq_num,
 169                        src->s6_addr32[0], src->s6_addr32[1],
 170                        src->s6_addr32[2], src->s6_addr32[3], srcp,
 171                        dest->s6_addr32[0], dest->s6_addr32[1],
 172                        dest->s6_addr32[2], dest->s6_addr32[3], destp);
 173
 174         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
 175                        tw->tw_substate, 0, 0,
 176                        3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
 177                        tw->tw_refcnt.refs.counter, tw);
 178
 179         return 0;
 180 }
 181
 182 static int dump_req_sock(struct seq_file *seq, struct tcp_request_sock *treq,
 183                          uid_t uid, __u32 seq_num)
 184 {
 185         struct inet_request_sock *irsk = &treq->req;
 186         struct request_sock *req = &irsk->req;
 187         struct in6_addr *src, *dest;
 188         long ttd;
 189
 190         ttd = req->rsk_timer.expires - bpf_jiffies64();
 191         src = &irsk->ir_v6_loc_addr;
 192         dest = &irsk->ir_v6_rmt_addr;
 193
 194         if (ttd < 0)
 195                 ttd = 0;
 196
 197         BPF_SEQ_PRINTF(seq, "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ",
 198                        seq_num,
 199                        src->s6_addr32[0], src->s6_addr32[1],
 200                        src->s6_addr32[2], src->s6_addr32[3],
 201                        irsk->ir_num,
 202                        dest->s6_addr32[0], dest->s6_addr32[1],
 203                        dest->s6_addr32[2], dest->s6_addr32[3],
 204                        bpf_ntohs(irsk->ir_rmt_port));
 205         BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK\n",
 206                        TCP_SYN_RECV, 0, 0, 1, jiffies_to_clock_t(ttd),
 207                        req->num_timeout, uid, 0, 0, 0, req);
 208
 209         return 0;
 210 }
 211
 212 SEC("iter/tcp")
 213 int dump_tcp6(struct bpf_iter__tcp *ctx)
 214 {
 215         struct sock_common *sk_common = ctx->sk_common;
 216         struct seq_file *seq = ctx->meta->seq;
 217         struct tcp_timewait_sock *tw;
 218         struct tcp_request_sock *req;
 219         struct tcp6_sock *tp;
 220         uid_t uid = ctx->uid;
 221         __u32 seq_num;
 222
 223         if (sk_common == (void *)0)
 224                 return 0;
 225
 226         seq_num = ctx->meta->seq_num;
 227         if (seq_num == 0)
 228                 BPF_SEQ_PRINTF(seq, "  sl  "
 229                                     "local_address                         "
 230                                     "remote_address                        "
 231                                     "st tx_queue rx_queue tr tm->when retrnsmt"
 232                                     "   uid  timeout inode\n");
 233
 234         if (sk_common->skc_family != AF_INET6)
 235                 return 0;
 236
 237         tp = bpf_skc_to_tcp6_sock(sk_common);
 238         if (tp)
 239                 return dump_tcp6_sock(seq, tp, uid, seq_num);
 240
 241         tw = bpf_skc_to_tcp_timewait_sock(sk_common);
 242         if (tw)
 243                 return dump_tw_sock(seq, tw, uid, seq_num);
 244
 245         req = bpf_skc_to_tcp_request_sock(sk_common);
 246         if (req)
 247                 return dump_req_sock(seq, req, uid, seq_num);
 248
 249         return 0;
 250 }