1.\" Copyright (c) 2015 Mark Johnston <markj@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd April 18, 2015 28.Dt DTRACE_UDP 4 29.Os 30.Sh NAME 31.Nm dtrace_udp 32.Nd a DTrace provider for tracing events related to the UDP protocol 33.Sh SYNOPSIS 34.Fn udp:::receive "pktinfo_t *" "csinfo_t *" "ipinfo_t *" "udpsinfo_t *" \ 35 "udpinfo_t *" 36.Fn udp:::send "pktinfo_t *" "csinfo_t *" "ipinfo_t *" "udpsinfo_t *" \ 37 "udpinfo_t *" 38.Sh DESCRIPTION 39The DTrace 40.Nm udp 41provider allows users to trace events in the 42.Xr udp 4 43protocol implementation. 44The 45.Fn udp:::send 46probe fires whenever the kernel prepares to transmit a UDP packet, and the 47.Fn udp:::receive 48probe fires whenever the kernel receives a UDP packet. 49The arguments to these probes can be used to obtain detailed information about 50the IP and UDP headers of the corresponding packet. 51.Sh ARGUMENTS 52The 53.Vt pktinfo_t 54argument is currently unimplemented and is included for compatibility with other 55implementations of this provider. 56Its fields are: 57.Bl -tag -width "uintptr_t pkt_addr" -offset indent 58.It Vt uintptr_t pkt_addr 59Always set to 0. 60.El 61.Pp 62The 63.Vt csinfo_t 64argument is currently unimplemented and is included for compatibility with other 65implementations of this provider. 66Its fields are: 67.Bl -tag -width "uintptr_t cs_addr" -offset indent 68.It Vt uintptr_t cs_addr 69Always set to 0. 70.It Vt uint64_t cs_cid 71A pointer to the 72.Vt struct inpcb 73for this packet, or 74.Dv NULL . 75.It Vt pid_t cs_pid 76Always set to 0. 77.El 78.Pp 79The 80.Vt ipinfo_t 81argument contains IP fields common to both IPv4 and IPv6 packets. 82Its fields are: 83.Bl -tag -width "uint32_t ip_plength" -offset indent 84.It Vt uint8_t ip_ver 85IP version of the packet, 4 for IPv4 packets and 6 for IPv6 packets. 86.It Vt uint32_t ip_plength 87IP payload size. 88This does not include the size of the IP header or IPv6 option headers. 89.It Vt string ip_saddr 90IP source address. 91.It Vt string ip_daddr 92IP destination address. 93.El 94.Pp 95The 96.Vt udpsinfo_t 97argument contains the state of the UDP connection associated with the packet. 98Its fields are: 99.Bl -tag -width "uintptr_t udps_addr" -offset indent 100.It Vt uintptr_t udps_addr 101Pointer to the 102.Vt struct inpcb 103containing the IP state for the associated socket. 104.It Vt uint16_t udps_lport 105Local UDP port. 106.It Vt uint16_t udps_rport 107Remote UDP port. 108.It Vt string udps_laddr 109Local IPv4 or IPv6 address. 110.It Vt string udps_raddr 111Remote IPv4 or IPv6 address. 112.El 113.Pp 114The 115.Vt udpinfo_t 116argument is the raw UDP header of the packet, with all fields in host order. 117Its fields are: 118.Bl -tag -width "struct udphdr *udp_hdr" -offset indent 119.It Vt uint16_t udp_sport 120Source UDP port. 121.It Vt uint16_t udp_dport 122Destination UDP port. 123.It Vt uint16_t udp_length 124Length of the UDP header and payload, in bytes. 125.It Vt uint16_t udp_checksum 126A checksum of the UDP header and payload, or 0 if no checksum was calculated. 127.It Vt struct udphdr *udp_hdr 128A pointer to the raw UDP header. 129.El 130.Sh FILES 131.Bl -tag -width "/usr/lib/dtrace/udp.d" -compact 132.It Pa /usr/lib/dtrace/udp.d 133DTrace type and translator definitions for the 134.Nm udp 135provider. 136.El 137.Sh EXAMPLES 138The following script counts transmitted packets by destination port. 139.Bd -literal -offset indent 140udp:::send 141{ 142 @num[args[4]->udp_dport] = count(); 143} 144.Ed 145.Pp 146This script will print some details of each UDP packet as it is sent or received 147by the kernel: 148.Bd -literal -offset indent 149#pragma D option quiet 150#pragma D option switchrate=10Hz 151 152dtrace:::BEGIN 153{ 154 printf(" %10s %36s %-36s %6s\\n", "DELTA(us)", "SOURCE", 155 "DEST", "BYTES"); 156 last = timestamp; 157} 158 159udp:::send 160{ 161 this->elapsed = (timestamp - last) / 1000; 162 self->dest = strjoin(strjoin(args[2]->ip_daddr, ":"), 163 lltostr(args[4]->udp_dport)); 164 printf(" %10d %30s:%-5d -> %-36s %6d\\n", this->elapsed, 165 args[2]->ip_saddr, args[4]->udp_sport, 166 self->dest, args[4]->udp_length); 167 last = timestamp; 168} 169 170udp:::receive 171{ 172 this->elapsed = (timestamp - last) / 1000; 173 self->dest = strjoin(strjoin(args[2]->ip_saddr, ":"), 174 lltostr(args[4]->udp_sport)); 175 printf(" %10d %30s:%-5d <- %-36s %6d\\n", this->elapsed, 176 args[2]->ip_daddr, args[4]->udp_dport, 177 self->dest, args[4]->udp_length); 178 last = timestamp; 179} 180.Ed 181.Sh COMPATIBILITY 182This provider is compatible with the 183.Nm udp 184provider in Solaris. 185.Sh SEE ALSO 186.Xr dtrace 1 , 187.Xr dtrace_ip 4 , 188.Xr dtrace_tcp 4 , 189.Xr udp 4 , 190.Xr SDT 9 191.Sh HISTORY 192The 193.Nm udp 194provider first appeared in 195.Fx 19610.0. 197.Sh AUTHORS 198This manual page was written by 199.An Mark Johnston Aq Mt markj@FreeBSD.org . 200