The SSL Debugging Tool 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.
ssltap command opens a socket on a rendezvous port and waits for an incoming connection from the
client side. Once this connection arrives, the tool makes another connection to the specified host name and port on
the server side. It passes any data sent by the client to the server and vice versa. The tool also displays the data
to the shell window from which it was called. It can do this for plain HTTP connections or any TCP protocol, as well
as for SSL streams, as described here.
The tool cannot and does not decrypt any encrypted message data. You use the tool to look at the plain text and
binary data that are part of the handshake procedure, before the secure connection is established.
ssltap [-vhfsxl] [-p port] hostname:port
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:80The 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:
<-- [ 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.
s and x options in this example turn on SSL parsing and show undecoded values in
hex/ASCII format. The output is routed to a text file.
ssltap.exe -sx -p 444 interzone.mcom.com:443 > sx.txt
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.
-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.exe -s -p 444 interzone.mcom.com:443 > s.txt
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.
-h option turns hex/ASCII format. There is no SSL parsing or decoding. The output
is routed to a text file.
ssltap.exe -h -p 444 interzone.mcom.com:443 > h.txt
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.
-s option turns on SSL parsing, and the -h options turns on hex/ASCII
format. Both formats are shown for each record. The output is routed to a text file.
ssltap.exe -hs -p 444 interzone.mcom.com:443 > hs.txt
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.