tcpv4connect
diff --git a/tools/tcpv4connect b/tools/tcpv4connect
new file mode 100755
index 0000000..fdada97
--- /dev/null
+++ b/tools/tcpv4connect
@@ -0,0 +1,122 @@
+#!/usr/bin/python
+#
+# tcpv4connect Trace TCP IPv4 connect()s.
+# For Linux, uses BCC, eBPF. Embedded C.
+#
+# USAGE: tcpv4connect [-h] [-t] [-p PID]
+#
+# Copyright (c) 2015 Brendan Gregg.
+# Licensed under the Apache License, Version 2.0 (the "License")
+#
+# 25-Sep-2015 Brendan Gregg Created this.
+
+from __future__ import print_function
+from bcc import BPF
+import argparse
+
+# arguments
+examples = """examples:
+ ./tcpv4connect # trace all open() syscalls
+ ./tcpv4connect -t # include timestamps
+ ./tcpv4connect -p 181 # only trace PID 181
+"""
+parser = argparse.ArgumentParser(
+ description="Trace TCP IPv4 connects",
+ 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>
+
+BPF_HASH(currsock, u32, struct sock *);
+
+int kprobe__tcp_v4_connect(struct pt_regs *ctx, struct sock *sk)
+{
+ u32 pid = bpf_get_current_pid_tgid();
+ FILTER
+
+ // stash the sock ptr for lookup on return
+ currsock.update(&pid, &sk);
+
+ return 0;
+};
+
+int kretprobe__tcp_v4_connect(struct pt_regs *ctx)
+{
+ int ret = ctx->ax;
+ u32 pid = bpf_get_current_pid_tgid();
+
+ struct sock **skpp;
+ skpp = currsock.lookup(&pid);
+ if (skpp == 0) {
+ return 0; // missed entry
+ }
+
+ // pull in details
+ struct sock *skp = *skpp;
+ u32 saddr = 0, daddr = 0;
+ u16 dport = 0;
+ bpf_probe_read(&saddr, sizeof(saddr), &skp->__sk_common.skc_rcv_saddr);
+ bpf_probe_read(&daddr, sizeof(daddr), &skp->__sk_common.skc_daddr);
+ bpf_probe_read(&dport, sizeof(dport), &skp->__sk_common.skc_dport);
+
+ // output
+ bpf_trace_printk("%x %x %d\\n", saddr, daddr, ntohs(dport));
+
+ currsock.delete(&pid);
+
+ 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 %-16s %-16s %-4s" % ("PID", "COMM", "SADDR", "DADDR",
+ "DPORT"))
+
+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()
+ (saddr_hs, daddr_hs, dport_s) = msg.split(" ")
+
+ if args.timestamp:
+ if start_ts == 0:
+ start_ts = ts
+ print("%-9.3f" % (ts - start_ts), end="")
+ print("%-6d %-12.12s %-16s %-16s %-4s" % (pid, task,
+ inet_ntoa(int(saddr_hs, 16)),
+ inet_ntoa(int(daddr_hs, 16)),
+ dport_s))