tcpaccept
diff --git a/tools/tcpaccept b/tools/tcpaccept
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--- /dev/null
+++ b/tools/tcpaccept
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+#!/usr/bin/python
+#
+# tcpaccept Trace TCP accept()s.
+# For Linux, uses BCC, eBPF. Embedded C.
+#
+# USAGE: tcpaccept [-h] [-t] [-p PID]
+#
+# This uses dynamic tracing of the kernel inet_csk_accept() socket function
+# (from tcp_prot.accept), and will need to be modified to match kernel changes.
+# This also traces DCCP traffic; check for future versions where this should
+# be filtered (should be done via "sk_protocol != IPPROTO_TCP").
+#
+# IPv4 addresses are printed as dotted quads. For IPv6 addresses, the last four
+# bytes are printed after "..."; check for future versions with better IPv6
+# support.
+#
+# Copyright (c) 2015 Brendan Gregg.
+# Licensed under the Apache License, Version 2.0 (the "License")
+#
+# 13-Oct-2015 Brendan Gregg Created this.
+
+from __future__ import print_function
+from bcc import BPF
+import argparse
+
+# arguments
+examples = """examples:
+ ./tcpaccept # trace all open() syscalls
+ ./tcpaccept -t # include timestamps
+ ./tcpaccept -p 181 # only trace PID 181
+"""
+parser = argparse.ArgumentParser(
+ description="Trace TCP accepts",
+ formatter_class=argparse.RawDescriptionHelpFormatter,
+ epilog=examples)
+parser.add_argument("-t", "--timestamp", action="store_true",
+ help="include timestamp on output")
+parser.add_argument("-p", "--pid",
+ help="trace this PID only")
+args = parser.parse_args()
+debug = 0
+
+# define BPF program
+bpf_text = """
+#include <uapi/linux/ptrace.h>
+#include <net/sock.h>
+#include <bcc/proto.h>
+
+int kretprobe__inet_csk_accept(struct pt_regs *ctx)
+{
+ struct sock *newsk = (struct sock *)ctx->ax;
+ u32 pid = bpf_get_current_pid_tgid();
+
+ if (newsk == NULL)
+ return 0;
+
+ // pull in details
+ u16 family = 0, lport = 0;
+ u32 saddr = 0, daddr = 0;
+ bpf_probe_read(&family, sizeof(family), &newsk->__sk_common.skc_family);
+ bpf_probe_read(&lport, sizeof(lport), &newsk->__sk_common.skc_num);
+ if (family == AF_INET) {
+ bpf_probe_read(&saddr, sizeof(saddr),
+ &newsk->__sk_common.skc_rcv_saddr);
+ bpf_probe_read(&daddr, sizeof(daddr),
+ &newsk->__sk_common.skc_daddr);
+
+ // output
+ bpf_trace_printk("4 %x %x %d\\n", daddr, saddr, lport);
+ } else if (family == AF_INET6) {
+ // just grab the last 4 bytes for now
+ bpf_probe_read(&saddr, sizeof(saddr),
+ &newsk->__sk_common.skc_v6_rcv_saddr.in6_u.u6_addr32[3]);
+ bpf_probe_read(&daddr, sizeof(daddr),
+ &newsk->__sk_common.skc_v6_daddr.in6_u.u6_addr32[3]);
+
+ // output and flip byte order of addresses
+ bpf_trace_printk("6 %x %x %d\\n", bpf_ntohl(daddr),
+ bpf_ntohl(saddr), lport);
+ }
+ // else drop
+
+ return 0;
+}
+"""
+
+# code substitutions
+if args.pid:
+ bpf_text = bpf_text.replace('FILTER',
+ 'if (pid != %s) { return 0; }' % args.pid)
+else:
+ bpf_text = bpf_text.replace('FILTER', '')
+if debug:
+ print(bpf_text)
+
+# initialize BPF
+b = BPF(text=bpf_text)
+
+# header
+if args.timestamp:
+ print("%-9s" % ("TIME(s)"), end="")
+print("%-6s %-12s %-2s %-16s %-16s %-4s" % ("PID", "COMM", "IP", "RADDR",
+ "LADDR", "LPORT"))
+
+start_ts = 0
+
+def inet_ntoa(addr):
+ dq = ''
+ for i in range(0, 4):
+ dq = dq + str(addr & 0xff)
+ if (i != 3):
+ dq = dq + '.'
+ addr = addr >> 8
+ return dq
+
+# format output
+while 1:
+ (task, pid, cpu, flags, ts, msg) = b.trace_fields()
+ (ip_s, raddr_hs, laddr_hs, lport_s) = msg.split(" ")
+
+ if args.timestamp:
+ if start_ts == 0:
+ start_ts = ts
+ print("%-9.3f" % (ts - start_ts), end="")
+ print("%-6d %-12.12s %-2s %-16s %-16s %-4s" % (pid, task, ip_s,
+ inet_ntoa(int(raddr_hs, 16)) if ip_s == "4" else "..." + raddr_hs,
+ inet_ntoa(int(laddr_hs, 16)) if ip_s == "4" else "..." + laddr_hs,
+ lport_s))