NSS tools : ssltap

Name

   ssltap — Tap into SSL connections and display the data going by

Synopsis

   libssltap [-vhfsxl] [-p port] [hostname:port]

Description

   The SSL Debugging Tool ssltap is an SSL-aware command-line proxy. It
   watches TCP connections and displays the data going by. If a connection is
   SSL, the data display includes interpreted SSL records and handshaking

Options

   -v

           Print a version string for the tool.

   -h

           Turn on hex/ASCII printing. Instead of outputting raw data, the
           command interprets each record as a numbered line of hex values,
           followed by the same data as ASCII characters. The two parts are
           separated by a vertical bar. Nonprinting characters are replaced
           by dots.

   -f

           Turn on fancy printing. Output is printed in colored HTML. Data
           sent from the client to the server is in blue; the server's reply
           is in red. When used with looping mode, the different connections
           are separated with horizontal lines. You can use this option to
           upload the output into a browser.

   -s

           Turn on SSL parsing and decoding. The tool does not automatically
           detect SSL sessions. If you are intercepting an SSL connection,
           use this option so that the tool can detect and decode SSL
           structures.

           If the tool detects a certificate chain, it saves the DER-encoded
           certificates into files in the current directory. The files are
           named cert.0x, where x is the sequence number of the certificate.

           If the -s option is used with -h, two separate parts are printed
           for each record: the plain hex/ASCII output, and the parsed SSL
           output.

   -x

           Turn on hex/ASCII printing of undecoded data inside parsed SSL
           records. Used only with the -s option. This option uses the same
           output format as the -h option.

   -l prefix

           Turn on looping; that is, continue to accept connections rather
           than stopping after the first connection is complete.

   -p port

           Change the default rendezvous port (1924) to another port.

           The following are well-known port numbers:

           * HTTP 80

           * HTTPS 443

           * SMTP 25

           * FTP 21

           * IMAP 143

           * IMAPS 993 (IMAP over SSL)

           * NNTP 119

           * NNTPS 563 (NNTP over SSL)

Usage and Examples

   You can use the SSL Debugging Tool to intercept any connection
   information. Although you can run the tool at its most basic by issuing
   the ssltap command with no options other than hostname:port, the
   information you get in this way is not very useful. For example, assume
   your development machine is called intercept. The simplest way to use the
   debugging tool is to execute the following command from a command shell:

 $ ssltap www.netscape.com

   The program waits for an incoming connection on the default port 1924. In
   your browser window, enter the URL http://intercept:1924. The browser
   retrieves the requested page from the server at www.netscape.com, but the
   page is intercepted and passed on to the browser by the debugging tool on
   intercept. On its way to the browser, the data is printed to the command
   shell from which you issued the command. Data sent from the client to the
   server is surrounded by the following symbols: --> [ data ] Data sent from
   the server to the client is surrounded by the following symbols: "left
   arrow"-- [ data ] The raw data stream is sent to standard output and is
   not interpreted in any way. This can result in peculiar effects, such as
   sounds, flashes, and even crashes of the command shell window. To output a
   basic, printable interpretation of the data, use the -h option, or, if you
   are looking at an SSL connection, the -s option. You will notice that the
   page you retrieved looks incomplete in the browser. This is because, by
   default, the tool closes down after the first connection is complete, so
   the browser is not able to load images. To make the tool continue to
   accept connections, switch on looping mode with the -l option. The
   following examples show the output from commonly used combinations of
   options.

   Example 1

 $ ssltap.exe -sx -p 444 interzone.mcom.com:443 > sx.txt

   Output

 Connected to interzone.mcom.com:443
 -->; [
 alloclen = 66 bytes
    [ssl2]  ClientHelloV2 {
             version = {0x03, 0x00}
             cipher-specs-length = 39 (0x27)
             sid-length = 0 (0x00)
             challenge-length = 16 (0x10)
             cipher-suites = {

                 (0x010080) SSL2/RSA/RC4-128/MD5
                   (0x020080) SSL2/RSA/RC4-40/MD5
                   (0x030080) SSL2/RSA/RC2CBC128/MD5
                   (0x040080) SSL2/RSA/RC2CBC40/MD5
                   (0x060040) SSL2/RSA/DES64CBC/MD5
                   (0x0700c0) SSL2/RSA/3DES192EDE-CBC/MD5
                   (0x000004) SSL3/RSA/RC4-128/MD5
                   (0x00ffe0) SSL3/RSA-FIPS/3DES192EDE-CBC/SHA
                   (0x00000a) SSL3/RSA/3DES192EDE-CBC/SHA
                   (0x00ffe1) SSL3/RSA-FIPS/DES64CBC/SHA
                   (0x000009) SSL3/RSA/DES64CBC/SHA
                   (0x000003) SSL3/RSA/RC4-40/MD5
                   (0x000006) SSL3/RSA/RC2CBC40/MD5
                   }
             session-id = { }
             challenge = { 0xec5d 0x8edb 0x37c9 0xb5c9 0x7b70 0x8fe9 0xd1d3

 0x2592 }
 }
 ]
 <-- [
 SSLRecord {
    0: 16 03 00 03  e5                                   |.....
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 997 (0x3e5)
    handshake {
    0: 02 00 00 46                                      |...F
       type = 2 (server_hello)
       length = 70 (0x000046)
             ServerHello {
             server_version = {3, 0}
             random = {...}
    0: 77 8c 6e 26  6c 0c ec c0  d9 58 4f 47  d3 2d 01 45  |
 wn&l.ì..XOG.-.E
    10: 5c 17 75 43  a7 4c 88 c7  88 64 3c 50  41 48 4f 7f  |

 \.uC§L.Ç.d<PAHO.
                   session ID = {
                   length = 32

                 contents = {..}
    0: 14 11 07 a8  2a 31 91 29  11 94 40 37  57 10 a7 32  | ...¨*1.)..@7W.§2
    10: 56 6f 52 62  fe 3d b3 65  b1 e4 13 0f  52 a3 c8 f6  | VoRbþ=³e±...R£È.
          }
                cipher_suite = (0x0003) SSL3/RSA/RC4-40/MD5
          }
    0: 0b 00 02 c5                                      |...Å
       type = 11 (certificate)
       length = 709 (0x0002c5)
             CertificateChain {
             chainlength = 706 (0x02c2)
                Certificate {
             size = 703 (0x02bf)
                data = { saved in file 'cert.001' }
             }
          }
    0: 0c 00 00 ca                                      |....
          type = 12 (server_key_exchange)
          length = 202 (0x0000ca)
    0: 0e 00 00 00                                      |....
          type = 14 (server_hello_done)
          length = 0 (0x000000)
    }
 }
 ]
 --> [
 SSLRecord {
    0: 16 03 00 00  44                                   |....D
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 68 (0x44)
    handshake {
    0: 10 00 00 40                                      |...@
    type = 16 (client_key_exchange)
    length = 64 (0x000040)
          ClientKeyExchange {
             message = {...}
          }
    }
 }
 ]
 --> [
 SSLRecord {
    0: 14 03 00 00  01                                   |.....
    type    = 20 (change_cipher_spec)
    version = { 3,0 }
    length  = 1 (0x1)
    0: 01                                               |.
 }
 SSLRecord {
    0: 16 03 00 00  38                                   |....8
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 56 (0x38)
                < encrypted >

 }
 ]
 <-- [
 SSLRecord {
    0: 14 03 00 00  01                                   |.....
    type    = 20 (change_cipher_spec)
    version = { 3,0 }
    length  = 1 (0x1)
    0: 01                                               |.
 }
 ]
 <-- [
 SSLRecord {
    0: 16 03 00 00  38                                   |....8
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 56 (0x38)
                   < encrypted >

 }
 ]
 --> [
 SSLRecord {
    0: 17 03 00 01  1f                                   |.....
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 287 (0x11f)
                < encrypted >
 }
 ]
 <-- [
 SSLRecord {
    0: 17 03 00 00  a0                                   |....
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 160 (0xa0)
                < encrypted >

 }
 ]
 <-- [
 SSLRecord {
 0: 17 03 00 00  df                                   |....ß
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 223 (0xdf)
                < encrypted >

 }
 SSLRecord {
    0: 15 03 00 00  12                                   |.....
    type    = 21 (alert)
    version = { 3,0 }
    length  = 18 (0x12)
                < encrypted >
 }
 ]
 Server socket closed.

   Example 2

   The -s option turns on SSL parsing. Because the -x option is not used in
   this example, undecoded values are output as raw data. The output is
   routed to a text file.

 $ ssltap -s  -p 444 interzone.mcom.com:443 > s.txt

   Output

 Connected to interzone.mcom.com:443
 --> [
 alloclen = 63 bytes
    [ssl2]  ClientHelloV2 {
             version = {0x03, 0x00}
             cipher-specs-length = 36 (0x24)
             sid-length = 0 (0x00)
             challenge-length = 16 (0x10)
             cipher-suites = {
                   (0x010080) SSL2/RSA/RC4-128/MD5
                   (0x020080) SSL2/RSA/RC4-40/MD5
                   (0x030080) SSL2/RSA/RC2CBC128/MD5
                   (0x060040) SSL2/RSA/DES64CBC/MD5
                   (0x0700c0) SSL2/RSA/3DES192EDE-CBC/MD5
                   (0x000004) SSL3/RSA/RC4-128/MD5
                   (0x00ffe0) SSL3/RSA-FIPS/3DES192EDE-CBC/SHA
                   (0x00000a) SSL3/RSA/3DES192EDE-CBC/SHA
                   (0x00ffe1) SSL3/RSA-FIPS/DES64CBC/SHA
                   (0x000009) SSL3/RSA/DES64CBC/SHA
                   (0x000003) SSL3/RSA/RC4-40/MD5
                   }
                session-id = { }
             challenge = { 0x713c 0x9338 0x30e1 0xf8d6 0xb934 0x7351 0x200c
 0x3fd0 }
 ]
 >-- [
 SSLRecord {
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 997 (0x3e5)
    handshake {
          type = 2 (server_hello)
          length = 70 (0x000046)
             ServerHello {
             server_version = {3, 0}
             random = {...}
             session ID = {
                length = 32
                contents = {..}
                }
                cipher_suite = (0x0003) SSL3/RSA/RC4-40/MD5
             }
          type = 11 (certificate)
          length = 709 (0x0002c5)
             CertificateChain {
                chainlength = 706 (0x02c2)
                Certificate {
                   size = 703 (0x02bf)
                   data = { saved in file 'cert.001' }
                }
             }
          type = 12 (server_key_exchange)
          length = 202 (0x0000ca)
          type = 14 (server_hello_done)
          length = 0 (0x000000)
    }
 }
 ]
 --> [
 SSLRecord {
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 68 (0x44)
    handshake {
          type = 16 (client_key_exchange)
          length = 64 (0x000040)
             ClientKeyExchange {
                message = {...}
             }
    }
 }
 ]
 --> [
 SSLRecord {
    type    = 20 (change_cipher_spec)
    version = { 3,0 }
    length  = 1 (0x1)
 }
 SSLRecord {
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 56 (0x38)
                > encrypted >
 }
 ]
 >-- [
 SSLRecord {
    type    = 20 (change_cipher_spec)
    version = { 3,0 }
    length  = 1 (0x1)
 }
 ]
 >-- [
 SSLRecord {
    type    = 22 (handshake)
    version = { 3,0 }
    length  = 56 (0x38)
                > encrypted >
 }
 ]
 --> [
 SSLRecord {
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 287 (0x11f)
                > encrypted >
 }
 ]
 [
 SSLRecord {
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 160 (0xa0)
                > encrypted >
 }
 ]
 >-- [
 SSLRecord {
    type    = 23 (application_data)
    version = { 3,0 }
    length  = 223 (0xdf)
                > encrypted >
 }
 SSLRecord {
    type    = 21 (alert)
    version = { 3,0 }
    length  = 18 (0x12)
                > encrypted >
 }
 ]
 Server socket closed.

   Example 3

   In this example, the -h option turns hex/ASCII format. There is no SSL
   parsing or decoding. The output is routed to a text file.

 $ ssltap -h  -p 444 interzone.mcom.com:443 > h.txt

   Output

 Connected to interzone.mcom.com:443
 --> [
    0: 80 40 01 03  00 00 27 00  00 00 10 01  00 80 02 00  | .@....'.........
    10: 80 03 00 80  04 00 80 06  00 40 07 00  c0 00 00 04  | .........@......
    20: 00 ff e0 00  00 0a 00 ff  e1 00 00 09  00 00 03 00  | ........á.......
    30: 00 06 9b fe  5b 56 96 49  1f 9f ca dd  d5 ba b9 52  | ..þ[V.I.\xd9 ...º¹R
    40: 6f 2d                                            |o-
 ]
 <-- [
    0: 16 03 00 03  e5 02 00 00  46 03 00 7f  e5 0d 1b 1d  | ........F.......
    10: 68 7f 3a 79  60 d5 17 3c  1d 9c 96 b3  88 d2 69 3b  | h.:y`..<..³.Òi;
    20: 78 e2 4b 8b  a6 52 12 4b  46 e8 c2 20  14 11 89 05  | x.K.¦R.KFè. ...
    30: 4d 52 91 fd  93 e0 51 48  91 90 08 96  c1 b6 76 77  | MR.ý..QH.....¶vw
    40: 2a f4 00 08  a1 06 61 a2  64 1f 2e 9b  00 03 00 0b  | *ô..¡.a¢d......
    50: 00 02 c5 00  02 c2 00 02  bf 30 82 02  bb 30 82 02  | ..Å......0...0..
    60: 24 a0 03 02  01 02 02 02  01 36 30 0d  06 09 2a 86  | $ .......60...*.
    70: 48 86 f7 0d  01 01 04 05  00 30 77 31  0b 30 09 06  | H.÷......0w1.0..
    80: 03 55 04 06  13 02 55 53  31 2c 30 2a  06 03 55 04  | .U....US1,0*..U.
    90: 0a 13 23 4e  65 74 73 63  61 70 65 20  43 6f 6d 6d  | ..#Netscape Comm
    a0: 75 6e 69 63  61 74 69 6f  6e 73 20 43  6f 72 70 6f  | unications Corpo
    b0: 72 61 74 69  6f 6e 31 11  30 0f 06 03  55 04 0b 13  | ration1.0...U...
    c0: 08 48 61 72  64 63 6f 72  65 31 27 30  25 06 03 55  | .Hardcore1'0%..U
    d0: 04 03 13 1e  48 61 72 64  63 6f 72 65  20 43 65 72  | ....Hardcore Cer
    e0: 74 69 66 69  63 61 74 65  20 53 65 72  76 65 72 20  | tificate Server
    f0: 49 49 30 1e  17 0d 39 38  30 35 31 36  30 31 30 33  | II0...9805160103
 <additional data lines>
 ]
 <additional records in same format>
 Server socket closed.

   Example 4

   In this example, the -s option turns on SSL parsing, and the -h option
   turns on hex/ASCII format. Both formats are shown for each record. The
   output is routed to a text file.

 $ ssltap -hs -p 444 interzone.mcom.com:443 > hs.txt

   Output

 Connected to interzone.mcom.com:443
 --> [
    0: 80 3d 01 03  00 00 24 00  00 00 10 01  00 80 02 00  | .=....$.........
    10: 80 03 00 80  04 00 80 06  00 40 07 00  c0 00 00 04  | .........@......
    20: 00 ff e0 00  00 0a 00 ff  e1 00 00 09  00 00 03 03  | ........á.......
    30: 55 e6 e4 99  79 c7 d7 2c  86 78 96 5d  b5 cf e9     |U..yÇ\xb0 ,.x.]µÏé
 alloclen = 63 bytes
    [ssl2]  ClientHelloV2 {
             version = {0x03, 0x00}
             cipher-specs-length = 36 (0x24)
             sid-length = 0 (0x00)
             challenge-length = 16 (0x10)
             cipher-suites = {
                   (0x010080) SSL2/RSA/RC4-128/MD5
                   (0x020080) SSL2/RSA/RC4-40/MD5
                   (0x030080) SSL2/RSA/RC2CBC128/MD5
                   (0x040080) SSL2/RSA/RC2CBC40/MD5
                   (0x060040) SSL2/RSA/DES64CBC/MD5
                   (0x0700c0) SSL2/RSA/3DES192EDE-CBC/MD5
                   (0x000004) SSL3/RSA/RC4-128/MD5
                   (0x00ffe0) SSL3/RSA-FIPS/3DES192EDE-CBC/SHA
                   (0x00000a) SSL3/RSA/3DES192EDE-CBC/SHA
                   (0x00ffe1) SSL3/RSA-FIPS/DES64CBC/SHA
                   (0x000009) SSL3/RSA/DES64CBC/SHA
                   (0x000003) SSL3/RSA/RC4-40/MD5
                   }
             session-id = { }
             challenge = { 0x0355 0xe6e4 0x9979 0xc7d7 0x2c86 0x7896 0x5db

 0xcfe9 }
 }
 ]
 <additional records in same formats>
 Server socket closed.

Usage Tips

   When SSL restarts a previous session, it makes use of cached information
   to do a partial handshake. If you wish to capture a full SSL handshake,
   restart the browser to clear the session id cache.

   If you run the tool on a machine other than the SSL server to which you
   are trying to connect, the browser will complain that the host name you
   are trying to connect to is different from the certificate. If you are
   using the default BadCert callback, you can still connect through a
   dialog. If you are not using the default BadCert callback, the one you
   supply must allow for this possibility.

See Also

   The NSS Security Tools are also documented at
   [1]http://www.mozilla.org/projects/security/pki/nss/.

Additional Resources

   NSS is maintained in conjunction with PKI and security-related projects
   through Mozilla dn Fedora. The most closely-related project is Dogtag PKI,
   with a project wiki at [2]http://pki.fedoraproject.org/wiki/.

   For information specifically about NSS, the NSS project wiki is located at
   [3]http://www.mozilla.org/projects/security/pki/nss/. The NSS site relates
   directly to NSS code changes and releases.

   Mailing lists: pki-devel@redhat.com and pki-users@redhat.com

   IRC: Freenode at #dogtag-pki

Authors

   The NSS tools were written and maintained by developers with Netscape and
   now with Red Hat and Sun.

   Authors: Elio Maldonado <emaldona@redhat.com>, Deon Lackey
   <dlackey@redhat.com>.

Copyright

   (c) 2010, Red Hat, Inc. Licensed under the GNU Public License version 2.

References

   Visible links
   1. http://www.mozilla.org/projects/secu.../pki/nss/tools
   2. http://pki.fedoraproject.org/wiki/
   3. http://www.mozilla.org/projects/security/pki/nss/

Document Tags and Contributors

 Contributors to this page: fscholz, emaldona@redhat.com
 Last updated by: fscholz,