Bounds-check the individual components of a SAP reply.

[tcpdump] / tcpdump.1

diff --git a/tcpdump.1 b/tcpdump.1
index 045415a3b080e8b897b15f11686b6e0c6887fa5b..b7cc99c6bd1910598c007f15d5c70d0b0473681f 100644 (file)
--- a/tcpdump.1
+++ b/tcpdump.1
@@ -1,4 +1,4 @@
-.\" @(#) $Header: /tcpdump/master/tcpdump/Attic/tcpdump.1,v 1.158 2004-01-22 09:35:50 hannes Exp $ (LBL)
+.\" @(#) $Header: /tcpdump/master/tcpdump/Attic/tcpdump.1,v 1.167.2.4 2005-05-02 21:27:34 guy Exp $ (LBL)

 .\"
 .\"    $NetBSD: tcpdump.8,v 1.9 2003/03/31 00:18:17 perry Exp $
 .\"
 .\"
 .\"    $NetBSD: tcpdump.8,v 1.9 2003/03/31 00:18:17 perry Exp $
 .\"


@@ -22,7 +22,7 @@
 .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 .\"
 .\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 .\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 .\"

-.TH TCPDUMP 1  "23 November 2003"
+.TH TCPDUMP 1  "18 April 2005"

 .SH NAME
 tcpdump \- dump traffic on a network
 .SH SYNOPSIS
 .SH NAME
 tcpdump \- dump traffic on a network
 .SH SYNOPSIS


@@ -54,12 +54,16 @@ tcpdump \- dump traffic on a network
 .I module
 ]
 [
 .I module
 ]
 [

-.B \-r
-.I file
+.B \-M
+.I secret

 ]
 .br
 .ti +8
 [
 ]
 .br
 .ti +8
 [

+.B \-r
+.I file
+]
+[

 .B \-s
 .I snaplen
 ]
 .B \-s
 .I snaplen
 ]


@@ -74,6 +78,12 @@ tcpdump \- dump traffic on a network
 .br
 .ti +8
 [
 .br
 .ti +8
 [

+.B \-W
+.I filecount
+]
+.br
+.ti +8
+[

 .B \-E
 .I spi@ipaddr algo:secret,...
 ]
 .B \-E
 .I spi@ipaddr algo:secret,...
 ]


@@ -247,7 +257,7 @@ currently larger than \fIfile_size\fP and, if so, close the current
 savefile and open a new one.  Savefiles after the first savefile will
 have the name specified with the
 .B \-w
 savefile and open a new one.  Savefiles after the first savefile will
 have the name specified with the
 .B \-w

-flag, with a number after it, starting at 2 and continuing upward.
+flag, with a number after it, starting at 1 and continuing upward.

 The units of \fIfile_size\fP are millions of bytes (1,000,000 bytes,
 not 1,048,576 bytes).
 .TP
 The units of \fIfile_size\fP are millions of bytes (1,000,000 bytes,
 not 1,048,576 bytes).
 .TP


@@ -381,6 +391,10 @@ Load SMI MIB module definitions from file \fImodule\fR.
 This option
 can be used several times to load several MIB modules into \fItcpdump\fP.
 .TP
 This option
 can be used several times to load several MIB modules into \fItcpdump\fP.
 .TP

+.B \-M
+Use \fIsecret\fP as a shared secret for validating the digests found in
+TCP segments with the TCP-MD5 option (RFC 2385), if present.
+.TP

 .B \-n
 Don't convert addresses (i.e., host addresses, port numbers, etc.) to names.
 .TP
 .B \-n
 Don't convert addresses (i.e., host addresses, port numbers, etc.) to names.
 .TP


@@ -520,6 +534,16 @@ them out.
 They can later be printed with the \-r option.
 Standard output is used if \fIfile\fR is ``-''.
 .TP
 They can later be printed with the \-r option.
 Standard output is used if \fIfile\fR is ``-''.
 .TP

+.B \-W
+Used in conjunction with the 
+.I \-C 
+option, this will limit the number
+of files created to the specified number, and begin overwriting files
+from the beginning, thus creating a 'rotating' buffer. 
+In addition, it will name
+the files with enough leading 0s to support the maximum number of
+files, allowing them to sort correctly.
+.TP

 .B \-x
 Print each packet (minus its link level header) in hex.
 The smaller of the entire packet or
 .B \-x
 Print each packet (minus its link level header) in hex.
 The smaller of the entire packet or


@@ -551,6 +575,8 @@ Drops privileges (if root) and changes user ID to
 .I user
 and the group ID to the primary group of
 .IR user .
 .I user
 and the group ID to the primary group of
 .IR user .

+.IP
+This behavior can also be enabled by default at compile time.

 .IP "\fI expression\fP"
 .RS
 selects which packets will be dumped.
 .IP "\fI expression\fP"
 .RS
 selects which packets will be dumped.


@@ -570,10 +596,11 @@ different kinds of qualifier:
 qualifiers say what kind of thing the id name or number refers to.
 Possible types are
 .BR host ,
 qualifiers say what kind of thing the id name or number refers to.
 Possible types are
 .BR host ,

-.B net
+.B net ,
+.B port

 and
 and

-.BR port .
-E.g., `host foo', `net 128.3', `port 20'.
+.BR portrange .
+E.g., `host foo', `net 128.3', `port 20', `portrange 6000-6008'.

 If there is no type
 qualifier,
 .B host
 If there is no type
 qualifier,
 .B host


@@ -615,7 +642,8 @@ protos are:
 .B tcp
 and
 .BR udp .
 .B tcp
 and
 .BR udp .

-E.g., `ether src foo', `arp net 128.3', `tcp port 21'.
+E.g., `ether src foo', `arp net 128.3', `tcp port 21', `udp portrange
+7000-7009'.

 If there is
 no proto qualifier, all protocols consistent with the type are
 assumed.
 If there is
 no proto qualifier, all protocols consistent with the type are
 assumed.


@@ -667,6 +695,7 @@ which may be either an address or a name.
 True if the IPv4/v6 source field of the packet is \fIhost\fP.
 .IP "\fBhost \fIhost\fP
 True if either the IPv4/v6 source or destination of the packet is \fIhost\fP.
 True if the IPv4/v6 source field of the packet is \fIhost\fP.
 .IP "\fBhost \fIhost\fP
 True if either the IPv4/v6 source or destination of the packet is \fIhost\fP.

+.IP

 Any of the above host expressions can be prepended with the keywords,
 \fBip\fP, \fBarp\fP, \fBrarp\fP, or \fBip6\fP as in:
 .in +.5i
 Any of the above host expressions can be prepended with the keywords,
 \fBip\fP, \fBarp\fP, \fBrarp\fP, or \fBip6\fP as in:
 .in +.5i


@@ -683,18 +712,18 @@ which is equivalent to:
 If \fIhost\fR is a name with multiple IP addresses, each address will
 be checked for a match.
 .IP "\fBether dst \fIehost\fP
 If \fIhost\fR is a name with multiple IP addresses, each address will
 be checked for a match.
 .IP "\fBether dst \fIehost\fP

-True if the ethernet destination address is \fIehost\fP.
+True if the Ethernet destination address is \fIehost\fP.

 \fIEhost\fP
 may be either a name from /etc/ethers or a number (see
 .IR ethers (3N)
 for numeric format).
 .IP "\fBether src \fIehost\fP
 \fIEhost\fP
 may be either a name from /etc/ethers or a number (see
 .IR ethers (3N)
 for numeric format).
 .IP "\fBether src \fIehost\fP

-True if the ethernet source address is \fIehost\fP.
+True if the Ethernet source address is \fIehost\fP.

 .IP "\fBether host \fIehost\fP
 .IP "\fBether host \fIehost\fP

-True if either the ethernet source or destination address is \fIehost\fP.
+True if either the Ethernet source or destination address is \fIehost\fP.

 .IP "\fBgateway\fP \fIhost\fP
 True if the packet used \fIhost\fP as a gateway.
 .IP "\fBgateway\fP \fIhost\fP
 True if the packet used \fIhost\fP as a gateway.

-I.e., the ethernet
+I.e., the Ethernet

 source or destination address was \fIhost\fP but neither the IP source
 nor the IP destination was \fIhost\fP.
 \fIHost\fP must be a name and
 source or destination address was \fIhost\fP but neither the IP source
 nor the IP destination was \fIhost\fP.
 \fIHost\fP must be a name and


@@ -721,7 +750,7 @@ number of \fInet\fP.
 True if either the IPv4/v6 source or destination address of the packet has a network
 number of \fInet\fP.
 .IP "\fBnet \fInet\fR \fBmask \fInetmask\fR"
 True if either the IPv4/v6 source or destination address of the packet has a network
 number of \fInet\fP.
 .IP "\fBnet \fInet\fR \fBmask \fInetmask\fR"

-True if the IP address matches \fInet\fR with the specific \fInetmask\fR.
+True if the IPv4 address matches \fInet\fR with the specific \fInetmask\fR.

 May be qualified with \fBsrc\fR or \fBdst\fR.
 Note that this syntax is not valid for IPv6 \fInet\fR.
 .IP "\fBnet \fInet\fR/\fIlen\fR"
 May be qualified with \fBsrc\fR or \fBdst\fR.
 Note that this syntax is not valid for IPv6 \fInet\fR.
 .IP "\fBnet \fInet\fR/\fIlen\fR"


@@ -745,8 +774,25 @@ both tcp/domain and udp/domain traffic).
 True if the packet has a source port value of \fIport\fP.
 .IP "\fBport \fIport\fR"
 True if either the source or destination port of the packet is \fIport\fP.
 True if the packet has a source port value of \fIport\fP.
 .IP "\fBport \fIport\fR"
 True if either the source or destination port of the packet is \fIport\fP.

-Any of the above port expressions can be prepended with the keywords,
-\fBtcp\fP or \fBudp\fP, as in:
+.IP "\fBdst portrange \fIport1\fB-\fIport2\fR"
+True if the packet is ip/tcp, ip/udp, ip6/tcp or ip6/udp and has a
+destination port value between \fIport1\fP and \fIport2\fP.
+.I port1
+and
+.I port2
+are interpreted in the same fashion as the
+.I port
+parameter for
+.BR port .
+.IP "\fBsrc portrange \fIport1\fB-\fIport2\fR"
+True if the packet has a source port value between \fIport1\fP and
+\fIport2\fP.
+.IP "\fBportrange \fIport1\fB-\fIport2\fR"
+True if either the source or destination port of the packet is between
+\fIport1\fP and \fIport2\fP.
+.IP
+Any of the above port or port range expressions can be prepended with
+the keywords, \fBtcp\fP or \fBudp\fP, as in:

 .in +.5i
 .nf
 \fBtcp src port \fIport\fR
 .in +.5i
 .nf
 \fBtcp src port \fIport\fR


@@ -770,13 +816,13 @@ This is equivalent to:
 .fi
 .in -.5i
 .IP "\fBip proto \fIprotocol\fR"
 .fi
 .in -.5i
 .IP "\fBip proto \fIprotocol\fR"

-True if the packet is an IP packet (see
+True if the packet is an IPv4 packet (see

 .IR ip (4P))
 of protocol type \fIprotocol\fP.
 \fIProtocol\fP can be a number or one of the names
 .IR ip (4P))
 of protocol type \fIprotocol\fP.
 \fIProtocol\fP can be a number or one of the names

-\fIicmp\fP, \fIicmp6\fP, \fIigmp\fP, \fIigrp\fP, \fIpim\fP, \fIah\fP,
-\fIesp\fP, \fIvrrp\fP, \fIudp\fP, or \fItcp\fP.
-Note that the identifiers \fItcp\fP, \fIudp\fP, and \fIicmp\fP are also
+\fBicmp\fP, \fBicmp6\fP, \fBigmp\fP, \fBigrp\fP, \fBpim\fP, \fBah\fP,
+\fBesp\fP, \fBvrrp\fP, \fBudp\fP, or \fBtcp\fP.
+Note that the identifiers \fBtcp\fP, \fBudp\fP, and \fBicmp\fP are also

 keywords and must be escaped via backslash (\\), which is \\\\ in the C-shell.
 Note that this primitive does not chase the protocol header chain.
 .IP "\fBip6 proto \fIprotocol\fR"
 keywords and must be escaped via backslash (\\), which is \\\\ in the C-shell.
 Note that this primitive does not chase the protocol header chain.
 .IP "\fBip6 proto \fIprotocol\fR"


@@ -802,7 +848,7 @@ so this can be somewhat slow.
 .IP "\fBip protochain \fIprotocol\fR"
 Equivalent to \fBip6 protochain \fIprotocol\fR, but this is for IPv4.
 .IP "\fBether broadcast\fR"
 .IP "\fBip protochain \fIprotocol\fR"
 Equivalent to \fBip6 protochain \fIprotocol\fR, but this is for IPv4.
 .IP "\fBether broadcast\fR"

-True if the packet is an ethernet broadcast packet.
+True if the packet is an Ethernet broadcast packet.

 The \fIether\fP
 keyword is optional.
 .IP "\fBip broadcast\fR"
 The \fIether\fP
 keyword is optional.
 .IP "\fBip broadcast\fR"


@@ -817,20 +863,20 @@ done has no netmask or because the capture is being done on the Linux
 "any" interface, which can capture on more than one interface, this
 check will not work correctly.
 .IP "\fBether multicast\fR"
 "any" interface, which can capture on more than one interface, this
 check will not work correctly.
 .IP "\fBether multicast\fR"

-True if the packet is an ethernet multicast packet.
-The \fIether\fP
+True if the packet is an Ethernet multicast packet.
+The \fBether\fP

 keyword is optional.
 This is shorthand for `\fBether[0] & 1 != 0\fP'.
 .IP "\fBip multicast\fR"
 keyword is optional.
 This is shorthand for `\fBether[0] & 1 != 0\fP'.
 .IP "\fBip multicast\fR"

-True if the packet is an IP multicast packet.
+True if the packet is an IPv4 multicast packet.

 .IP "\fBip6 multicast\fR"
 True if the packet is an IPv6 multicast packet.
 .IP  "\fBether proto \fIprotocol\fR"
 True if the packet is of ether type \fIprotocol\fR.
 \fIProtocol\fP can be a number or one of the names
 .IP "\fBip6 multicast\fR"
 True if the packet is an IPv6 multicast packet.
 .IP  "\fBether proto \fIprotocol\fR"
 True if the packet is of ether type \fIprotocol\fR.
 \fIProtocol\fP can be a number or one of the names

-\fIip\fP, \fIip6\fP, \fIarp\fP, \fIrarp\fP, \fIatalk\fP, \fIaarp\fP,
-\fIdecnet\fP, \fIsca\fP, \fIlat\fP, \fImopdl\fP, \fImoprc\fP,
-\fIiso\fP, \fIstp\fP, \fIipx\fP, or \fInetbeui\fP.
+\fBip\fP, \fBip6\fP, \fBarp\fP, \fBrarp\fP, \fBatalk\fP, \fBaarp\fP,
+\fBdecnet\fP, \fBsca\fP, \fBlat\fP, \fBmopdl\fP, \fBmoprc\fP,
+\fBiso\fP, \fBstp\fP, \fBipx\fP, or \fBnetbeui\fP.

 Note these identifiers are also keywords
 and must be escaped via backslash (\\).
 .IP
 Note these identifiers are also keywords
 and must be escaped via backslash (\\).
 .IP


@@ -853,10 +899,10 @@ The exceptions are:
 \fItcpdump\fR checks the DSAP (Destination Service Access Point) and
 SSAP (Source Service Access Point) fields of the LLC header;
 .TP
 \fItcpdump\fR checks the DSAP (Destination Service Access Point) and
 SSAP (Source Service Access Point) fields of the LLC header;
 .TP

-\fBstp\fP and \fInetbeui\fP
+\fBstp\fP and \fBnetbeui\fP

 \fItcpdump\fR checks the DSAP of the LLC header;
 .TP
 \fItcpdump\fR checks the DSAP of the LLC header;
 .TP

-\fIatalk\fP
+\fBatalk\fP

 \fItcpdump\fR checks for a SNAP-format packet with an OUI of 0x080007
 and the AppleTalk etype.
 .RE
 \fItcpdump\fR checks for a SNAP-format packet with an OUI of 0x080007
 and the AppleTalk etype.
 .RE


@@ -865,7 +911,7 @@ In the case of Ethernet, \fItcpdump\fR checks the Ethernet type field
 for most of those protocols.  The exceptions are:
 .RS
 .TP
 for most of those protocols.  The exceptions are:
 .RS
 .TP

-\fBiso\fP, \fBsap\fP, and \fBnetbeui\fP
+\fBiso\fP, \fBstp\fP, and \fBnetbeui\fP

 \fItcpdump\fR checks for an 802.3 frame and then checks the LLC header as
 it does for FDDI, Token Ring, and 802.11;
 .TP
 \fItcpdump\fR checks for an 802.3 frame and then checks the LLC header as
 it does for FDDI, Token Ring, and 802.11;
 .TP


@@ -923,6 +969,22 @@ and
 .B memory
 (applies only to packets logged by OpenBSD's
 .BR pf (4)).
 .B memory
 (applies only to packets logged by OpenBSD's
 .BR pf (4)).

+.IP "\fBrset \fIname\fR"
+True if the packet was logged as matching the specified PF ruleset
+name of an anchored ruleset (applies only to packets logged by
+.BR pf (4)).
+.IP "\fBruleset \fIname\fR"
+Synonomous with the
+.B rset
+modifier.
+.IP "\fBsrnr \fInum\fR"
+True if the packet was logged as matching the specified PF rule number
+of an anchored ruleset (applies only to packets logged by
+.BR pf (4)).
+.IP "\fBsubrulenum \fInum\fR"
+Synonomous with the
+.B srnr
+modifier.

 .IP "\fBaction \fIact\fR"
 True if PF took the specified action when the packet was logged.  Known actions
 are:
 .IP "\fBaction \fIact\fR"
 True if PF took the specified action when the packet was logged.  Known actions
 are:


@@ -930,7 +992,7 @@ are:
 and
 .B block
 (applies only to packets logged by OpenBSD's
 and
 .B block
 (applies only to packets logged by OpenBSD's

-.BR pf(4)).
+.BR pf (4)).

 .IP "\fBip\fR, \fBip6\fR, \fBarp\fR, \fBrarp\fR, \fBatalk\fR, \fBaarp\fR, \fBdecnet\fR, \fBiso\fR, \fBstp\fR, \fBipx\fR, \fInetbeui\fP"
 Abbreviations for:
 .in +.5i
 .IP "\fBip\fR, \fBip6\fR, \fBarp\fR, \fBrarp\fR, \fBatalk\fR, \fBaarp\fR, \fBdecnet\fR, \fBiso\fR, \fBstp\fR, \fBipx\fR, \fInetbeui\fP"
 Abbreviations for:
 .in +.5i


@@ -956,6 +1018,15 @@ If \fI[vlan_id]\fR is specified, only true is the packet has the specified
 Note that the first \fBvlan\fR keyword encountered in \fIexpression\fR
 changes the decoding offsets for the remainder of \fIexpression\fR
 on the assumption that the packet is a VLAN packet.
 Note that the first \fBvlan\fR keyword encountered in \fIexpression\fR
 changes the decoding offsets for the remainder of \fIexpression\fR
 on the assumption that the packet is a VLAN packet.

+the \fI[vlan_id]\fR statement may be used more than once, to filter on vlan hierarchies.
+each use of the \fI[vlan_id]\fR \fIexpression\fR increments the filter offsets by 4.
+.fi
+example(s):
+.fi
+"vlan 100 && vlan 200" filters on vlan 200 encapsulated within vlan 100
+.fi
+"vlan && vlan 300 && ip" filters IPv4 protocols encapsulated in vlan 300 encapsulated within any higher order vlan
+.fi

 .IP  "\fBtcp\fR, \fBudp\fR, \fBicmp\fR"
 Abbreviations for:
 .in +.5i
 .IP  "\fBtcp\fR, \fBudp\fR, \fBicmp\fR"
 Abbreviations for:
 .in +.5i


@@ -967,7 +1038,7 @@ where \fIp\fR is one of the above protocols.
 .IP "\fBiso proto \fIprotocol\fR"
 True if the packet is an OSI packet of protocol type \fIprotocol\fP.
 \fIProtocol\fP can be a number or one of the names
 .IP "\fBiso proto \fIprotocol\fR"
 True if the packet is an OSI packet of protocol type \fIprotocol\fP.
 \fIProtocol\fP can be a number or one of the names

-\fIclnp\fP, \fIesis\fP, or \fIisis\fP.
+\fBclnp\fP, \fBesis\fP, or \fBisis\fP.

 .IP "\fBclnp\fR, \fBesis\fR, \fBisis\fR"
 Abbreviations for:
 .in +.5i
 .IP "\fBclnp\fR, \fBesis\fR, \fBisis\fR"
 Abbreviations for:
 .in +.5i


@@ -1035,7 +1106,8 @@ True if the relation holds, where \fIrelop\fR is one of >, <, >=, <=, =,
 !=, and \fIexpr\fR is an arithmetic expression composed of integer
 constants (expressed in standard C syntax), the normal binary operators
 [+, -, *, /, &, |, <<, >>], a length operator, and special packet data
 !=, and \fIexpr\fR is an arithmetic expression composed of integer
 constants (expressed in standard C syntax), the normal binary operators
 [+, -, *, /, &, |, <<, >>], a length operator, and special packet data

-accessors.
+accessors.  Note that all comparisons are unsigned, so that, for example,
+0x80000000 and 0xffffffff are > 0.

 To access
 data inside the packet, use the following syntax:
 .in +.5i
 To access
 data inside the packet, use the following syntax:
 .in +.5i


@@ -1044,10 +1116,11 @@ data inside the packet, use the following syntax:
 .fi
 .in -.5i
 \fIProto\fR is one of \fBether, fddi, tr, wlan, ppp, slip, link,
 .fi
 .in -.5i
 \fIProto\fR is one of \fBether, fddi, tr, wlan, ppp, slip, link,

-ip, arp, rarp, tcp, udp, icmp\fR or \fBip6\fR, and
+ip, arp, rarp, tcp, udp, icmp, ip6\fR or \fBradio\fR, and

 indicates the protocol layer for the index operation.
 (\fBether, fddi, wlan, tr, ppp, slip\fR and \fBlink\fR all refer to the
 indicates the protocol layer for the index operation.
 (\fBether, fddi, wlan, tr, ppp, slip\fR and \fBlink\fR all refer to the

-link layer.)
+link layer. \fBradio\fR refers to the "radio header" added to some
+802.11 captures.)

 Note that \fItcp, udp\fR and other upper-layer protocol types only
 apply to IPv4, not IPv6 (this will be fixed in the future).
 The byte offset, relative to the indicated protocol layer, is
 Note that \fItcp, udp\fR and other upper-layer protocol types only
 apply to IPv4, not IPv6 (this will be fixed in the future).
 The byte offset, relative to the indicated protocol layer, is


@@ -1059,10 +1132,11 @@ length of the packet.
 
 For example, `\fBether[0] & 1 != 0\fP' catches all multicast traffic.
 The expression `\fBip[0] & 0xf != 5\fP'
 
 For example, `\fBether[0] & 1 != 0\fP' catches all multicast traffic.
 The expression `\fBip[0] & 0xf != 5\fP'

-catches all IP packets with options.
+catches all IPv4 packets with options.

 The expression
 `\fBip[6:2] & 0x1fff = 0\fP'
 The expression
 `\fBip[6:2] & 0x1fff = 0\fP'

-catches only unfragmented datagrams and frag zero of fragmented datagrams.
+catches only unfragmented IPv4 datagrams and frag zero of fragmented
+IPv4 datagrams.

 This check is implicitly applied to the \fBtcp\fP and \fBudp\fP
 index operations.
 For instance, \fBtcp[0]\fP always means the first
 This check is implicitly applied to the \fBtcp\fP and \fBudp\fP
 index operations.
 For instance, \fBtcp[0]\fP always means the first


@@ -1189,6 +1263,16 @@ tcpdump 'tcp[tcpflags] & (tcp-syn|tcp-fin) != 0 and not src and dst net \fIlocal
 .fi
 .RE
 .LP
 .fi
 .RE
 .LP

+To print all IPv4 HTTP packets to and from port 80, i.e. print only
+packets that contain data, not, for example, SYN and FIN packets and
+ACK-only packets.  (IPv6 is left as an exercise for the reader.)
+.RS
+.nf
+.B
+tcpdump 'tcp port 80 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)'
+.fi
+.RE
+.LP

 To print IP packets longer than 576 bytes sent through gateway \fIsnup\fP:
 .RS
 .nf
 To print IP packets longer than 576 bytes sent through gateway \fIsnup\fP:
 .RS
 .nf


@@ -1199,7 +1283,7 @@ tcpdump 'gateway snup and ip[2:2] > 576'
 .LP
 To print IP broadcast or multicast packets that were
 .I not
 .LP
 To print IP broadcast or multicast packets that were
 .I not

-sent via ethernet broadcast or multicast:
+sent via Ethernet broadcast or multicast:

 .RS
 .nf
 .B
 .RS
 .nf
 .B


@@ -1228,7 +1312,7 @@ gives a brief description and examples of most of the formats.
 Link Level Headers
 .LP
 If the '-e' option is given, the link level header is printed out.
 Link Level Headers
 .LP
 If the '-e' option is given, the link level header is printed out.

-On ethernets, the source and destination addresses, protocol,
+On Ethernets, the source and destination addresses, protocol,

 and packet length are printed.
 .LP
 On FDDI networks, the  '-e' option causes \fItcpdump\fP to print
 and packet length are printed.
 .LP
 On FDDI networks, the  '-e' option causes \fItcpdump\fP to print


@@ -1306,9 +1390,9 @@ arp reply csam is-at CSAM\fR
 .fi
 .RE
 The first line says that rtsg sent an arp packet asking
 .fi
 .RE
 The first line says that rtsg sent an arp packet asking

-for the ethernet address of internet host csam.
+for the Ethernet address of internet host csam.

 Csam
 Csam

-replies with its ethernet address (in this example, ethernet addresses
+replies with its Ethernet address (in this example, Ethernet addresses

 are in caps and internet addresses in lower case).
 .LP
 This would look less redundant if we had done \fItcpdump \-n\fP:
 are in caps and internet addresses in lower case).
 .LP
 This would look less redundant if we had done \fItcpdump \-n\fP:


@@ -1330,8 +1414,8 @@ CSAM RTSG 0806  64: arp reply csam is-at CSAM\fR
 .sp .5
 .fi
 .RE
 .sp .5
 .fi
 .RE

-For the first packet this says the ethernet source address is RTSG, the
-destination is the ethernet broadcast address, the type field
+For the first packet this says the Ethernet source address is RTSG, the
+destination is the Ethernet broadcast address, the type field

 contained hex 0806 (type ETHER_ARP) and the total length was 64 bytes.
 .HD
 TCP Packets
 contained hex 0806 (type ETHER_ARP) and the total length was 64 bytes.
 .HD
 TCP Packets


@@ -1759,11 +1843,6 @@ Be warned that with -v a single SMB packet
 may take up a page or more, so only use -v if you really want all the
 gory details.
 
 may take up a page or more, so only use -v if you really want all the
 gory details.
 

-If you are decoding SMB sessions containing unicode strings then you
-may wish to set the environment variable USE_UNICODE to 1.
-A patch to
-auto-detect unicode strings would be welcome.
-

 For information on SMB packet formats and what all te fields mean see
 www.cifs.org or the pub/samba/specs/ directory on your favorite
 samba.org mirror site.
 For information on SMB packet formats and what all te fields mean see
 www.cifs.org or the pub/samba/specs/ directory on your favorite
 samba.org mirror site.


@@ -2118,7 +2197,7 @@ and is as accurate as the kernel's clock.
 The timestamp reflects the time the kernel first saw the packet.
 No attempt
 is made to account for the time lag between when the
 The timestamp reflects the time the kernel first saw the packet.
 No attempt
 is made to account for the time lag between when the

-ethernet interface removed the packet from the wire and when the kernel
+Ethernet interface removed the packet from the wire and when the kernel

 serviced the `new packet' interrupt.
 .SH "SEE ALSO"
 stty(1), pcap(3), bpf(4), nit(4P), pfconfig(8)
 serviced the `new packet' interrupt.
 .SH "SEE ALSO"
 stty(1), pcap(3), bpf(4), nit(4P), pfconfig(8)