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CIPHERS

Section: OpenSSL (1SSL)
Updated: 2007-04-25
Index Return to Main Contents
 

NAME

ciphers - SSL cipher display and cipher list tool.  

SYNOPSIS

openssl ciphers [-v] [-ssl2] [-ssl3] [-tls1] [cipherlist]  

DESCRIPTION

The cipherlist command converts OpenSSL cipher lists into ordered SSL cipher preference lists. It can be used as a test tool to determine the appropriate cipherlist.  

COMMAND OPTIONS

-v
verbose option. List ciphers with a complete description of protocol version (SSLv2 or SSLv3; the latter includes TLS), key exchange, authentication, encryption and mac algorithms used along with any key size restrictions and whether the algorithm is classed as an export cipher. Note that without the -v option, ciphers may seem to appear twice in a cipher list; this is when similar ciphers are available for SSL v2 and for SSL v3/TLS v1.
-ssl3
only include SSL v3 ciphers.
-ssl2
only include SSL v2 ciphers.
-tls1
only include TLS v1 ciphers.
-h, -?
print a brief usage message.
cipherlist
a cipher list to convert to a cipher preference list. If it is not included then the default cipher list will be used. The format is described below.
 

CIPHER LIST FORMAT

The cipher list consists of one or more cipher strings separated by colons. Commas or spaces are also acceptable separators but colons are normally used.

The actual cipher string can take several different forms.

It can consist of a single cipher suite such as RC4-SHA.

It can represent a list of cipher suites containing a certain algorithm, or cipher suites of a certain type. For example SHA1 represents all ciphers suites using the digest algorithm SHA1 and SSLv3 represents all SSL v3 algorithms.

Lists of cipher suites can be combined in a single cipher string using the + character. This is used as a logical and operation. For example SHA1+DES represents all cipher suites containing the SHA1 and the DES algorithms.

Each cipher string can be optionally preceded by the characters !, - or +.

If ! is used then the ciphers are permanently deleted from the list. The ciphers deleted can never reappear in the list even if they are explicitly stated.

If - is used then the ciphers are deleted from the list, but some or all of the ciphers can be added again by later options.

If + is used then the ciphers are moved to the end of the list. This option doesn't add any new ciphers it just moves matching existing ones.

If none of these characters is present then the string is just interpreted as a list of ciphers to be appended to the current preference list. If the list includes any ciphers already present they will be ignored: that is they will not moved to the end of the list.

Additionally the cipher string @STRENGTH can be used at any point to sort the current cipher list in order of encryption algorithm key length.  

CIPHER STRINGS

The following is a list of all permitted cipher strings and their meanings.
DEFAULT
the default cipher list. This is determined at compile time and is normally AES:ALL:!aNULL:!eNULL:+RC4:@STRENGTH. This must be the first cipher string specified.
COMPLEMENTOFDEFAULT
the ciphers included in ALL, but not enabled by default. Currently this is ADH. Note that this rule does not cover eNULL, which is not included by ALL (use COMPLEMENTOFALL if necessary).
ALL
all ciphers suites except the eNULL ciphers which must be explicitly enabled.
COMPLEMENTOFALL
the cipher suites not enabled by ALL, currently being eNULL.
HIGH
high encryption cipher suites. This currently means those with key lengths larger than 128 bits, and some cipher suites with 128-bit keys.
MEDIUM
medium encryption cipher suites, currently some of those using 128 bit encryption.
LOW
low encryption cipher suites, currently those using 64 or 56 bit encryption algorithms but excluding export cipher suites.
EXP, EXPORT
export encryption algorithms. Including 40 and 56 bits algorithms.
EXPORT40
40 bit export encryption algorithms
EXPORT56
56 bit export encryption algorithms. In OpenSSL 0.9.8c and later the set of 56 bit export ciphers is empty unless OpenSSL has been explicitly configured with support for experimental ciphers.
eNULL, NULL
the NULL ciphers that is those offering no encryption. Because these offer no encryption at all and are a security risk they are disabled unless explicitly included.
aNULL
the cipher suites offering no authentication. This is currently the anonymous DH algorithms. These cipher suites are vulnerable to a man in the middle attack and so their use is normally discouraged.
kRSA, RSA
cipher suites using RSA key exchange.
kEDH
cipher suites using ephemeral DH key agreement.
kDHr, kDHd
cipher suites using DH key agreement and DH certificates signed by CAs with RSA and DSS keys respectively. Not implemented.
aRSA
cipher suites using RSA authentication, i.e. the certificates carry RSA keys.
aDSS, DSS
cipher suites using DSS authentication, i.e. the certificates carry DSS keys.
aDH
cipher suites effectively using DH authentication, i.e. the certificates carry DH keys. Not implemented.
kFZA, aFZA, eFZA, FZA
ciphers suites using FORTEZZA key exchange, authentication, encryption or all FORTEZZA algorithms. Not implemented.
TLSv1, SSLv3, SSLv2
TLS v1.0, SSL v3.0 or SSL v2.0 cipher suites respectively.
DH
cipher suites using DH, including anonymous DH.
ADH
anonymous DH cipher suites.
AES
cipher suites using AES.
CAMELLIA
cipher suites using Camellia.
3DES
cipher suites using triple DES.
DES
cipher suites using DES (not triple DES).
RC4
cipher suites using RC4.
RC2
cipher suites using RC2.
IDEA
cipher suites using IDEA.
SEED
cipher suites using SEED.
MD5
cipher suites using MD5.
SHA1, SHA
cipher suites using SHA1.
 

CIPHER SUITE NAMES

The following lists give the SSL or TLS cipher suites names from the relevant specification and their OpenSSL equivalents. It should be noted, that several cipher suite names do not include the authentication used, e.g. DES-CBC3-SHA. In these cases, RSA authentication is used.  

SSL v3.0 cipher suites.

SSL_RSA_WITH_NULL_MD5 NULL-MD5 SSL_RSA_WITH_NULL_SHA NULL-SHA SSL_RSA_EXPORT_WITH_RC4_40_MD5 EXP-RC4-MD5 SSL_RSA_WITH_RC4_128_MD5 RC4-MD5 SSL_RSA_WITH_RC4_128_SHA RC4-SHA SSL_RSA_EXPORT_WITH_RC2_CBC_40_MD5 EXP-RC2-CBC-MD5 SSL_RSA_WITH_IDEA_CBC_SHA IDEA-CBC-SHA SSL_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-DES-CBC-SHA SSL_RSA_WITH_DES_CBC_SHA DES-CBC-SHA SSL_RSA_WITH_3DES_EDE_CBC_SHA DES-CBC3-SHA SSL_DH_DSS_EXPORT_WITH_DES40_CBC_SHA Not implemented. SSL_DH_DSS_WITH_DES_CBC_SHA Not implemented. SSL_DH_DSS_WITH_3DES_EDE_CBC_SHA Not implemented. SSL_DH_RSA_EXPORT_WITH_DES40_CBC_SHA Not implemented. SSL_DH_RSA_WITH_DES_CBC_SHA Not implemented. SSL_DH_RSA_WITH_3DES_EDE_CBC_SHA Not implemented. SSL_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-DSS-DES-CBC-SHA SSL_DHE_DSS_WITH_DES_CBC_SHA EDH-DSS-CBC-SHA SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA EDH-DSS-DES-CBC3-SHA SSL_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-RSA-DES-CBC-SHA SSL_DHE_RSA_WITH_DES_CBC_SHA EDH-RSA-DES-CBC-SHA SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA EDH-RSA-DES-CBC3-SHA SSL_DH_anon_EXPORT_WITH_RC4_40_MD5 EXP-ADH-RC4-MD5 SSL_DH_anon_WITH_RC4_128_MD5 ADH-RC4-MD5 SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA EXP-ADH-DES-CBC-SHA SSL_DH_anon_WITH_DES_CBC_SHA ADH-DES-CBC-SHA SSL_DH_anon_WITH_3DES_EDE_CBC_SHA ADH-DES-CBC3-SHA SSL_FORTEZZA_KEA_WITH_NULL_SHA Not implemented. SSL_FORTEZZA_KEA_WITH_FORTEZZA_CBC_SHA Not implemented. SSL_FORTEZZA_KEA_WITH_RC4_128_SHA Not implemented.  

TLS v1.0 cipher suites.

TLS_RSA_WITH_NULL_MD5 NULL-MD5 TLS_RSA_WITH_NULL_SHA NULL-SHA TLS_RSA_EXPORT_WITH_RC4_40_MD5 EXP-RC4-MD5 TLS_RSA_WITH_RC4_128_MD5 RC4-MD5 TLS_RSA_WITH_RC4_128_SHA RC4-SHA TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 EXP-RC2-CBC-MD5 TLS_RSA_WITH_IDEA_CBC_SHA IDEA-CBC-SHA TLS_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-DES-CBC-SHA TLS_RSA_WITH_DES_CBC_SHA DES-CBC-SHA TLS_RSA_WITH_3DES_EDE_CBC_SHA DES-CBC3-SHA TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA Not implemented. TLS_DH_DSS_WITH_DES_CBC_SHA Not implemented. TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA Not implemented. TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA Not implemented. TLS_DH_RSA_WITH_DES_CBC_SHA Not implemented. TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA Not implemented. TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-DSS-DES-CBC-SHA TLS_DHE_DSS_WITH_DES_CBC_SHA EDH-DSS-CBC-SHA TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA EDH-DSS-DES-CBC3-SHA TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-RSA-DES-CBC-SHA TLS_DHE_RSA_WITH_DES_CBC_SHA EDH-RSA-DES-CBC-SHA TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA EDH-RSA-DES-CBC3-SHA TLS_DH_anon_EXPORT_WITH_RC4_40_MD5 EXP-ADH-RC4-MD5 TLS_DH_anon_WITH_RC4_128_MD5 ADH-RC4-MD5 TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA EXP-ADH-DES-CBC-SHA TLS_DH_anon_WITH_DES_CBC_SHA ADH-DES-CBC-SHA TLS_DH_anon_WITH_3DES_EDE_CBC_SHA ADH-DES-CBC3-SHA  

AES ciphersuites from RFC3268, extending TLS v1.0

TLS_RSA_WITH_AES_128_CBC_SHA AES128-SHA TLS_RSA_WITH_AES_256_CBC_SHA AES256-SHA TLS_DH_DSS_WITH_AES_128_CBC_SHA Not implemented. TLS_DH_DSS_WITH_AES_256_CBC_SHA Not implemented. TLS_DH_RSA_WITH_AES_128_CBC_SHA Not implemented. TLS_DH_RSA_WITH_AES_256_CBC_SHA Not implemented. TLS_DHE_DSS_WITH_AES_128_CBC_SHA DHE-DSS-AES128-SHA TLS_DHE_DSS_WITH_AES_256_CBC_SHA DHE-DSS-AES256-SHA TLS_DHE_RSA_WITH_AES_128_CBC_SHA DHE-RSA-AES128-SHA TLS_DHE_RSA_WITH_AES_256_CBC_SHA DHE-RSA-AES256-SHA TLS_DH_anon_WITH_AES_128_CBC_SHA ADH-AES128-SHA TLS_DH_anon_WITH_AES_256_CBC_SHA ADH-AES256-SHA  

Camellia ciphersuites from RFC4132, extending TLS v1.0

TLS_RSA_WITH_CAMELLIA_128_CBC_SHA CAMELLIA128-SHA TLS_RSA_WITH_CAMELLIA_256_CBC_SHA CAMELLIA256-SHA TLS_DH_DSS_WITH_CAMELLIA_128_CBC_SHA Not implemented. TLS_DH_DSS_WITH_CAMELLIA_256_CBC_SHA Not implemented. TLS_DH_RSA_WITH_CAMELLIA_128_CBC_SHA Not implemented. TLS_DH_RSA_WITH_CAMELLIA_256_CBC_SHA Not implemented. TLS_DHE_DSS_WITH_CAMELLIA_128_CBC_SHA DHE-DSS-CAMELLIA128-SHA TLS_DHE_DSS_WITH_CAMELLIA_256_CBC_SHA DHE-DSS-CAMELLIA256-SHA TLS_DHE_RSA_WITH_CAMELLIA_128_CBC_SHA DHE-RSA-CAMELLIA128-SHA TLS_DHE_RSA_WITH_CAMELLIA_256_CBC_SHA DHE-RSA-CAMELLIA256-SHA TLS_DH_anon_WITH_CAMELLIA_128_CBC_SHA ADH-CAMELLIA128-SHA TLS_DH_anon_WITH_CAMELLIA_256_CBC_SHA ADH-CAMELLIA256-SHA  

SEED ciphersuites from RFC4162, extending TLS v1.0

TLS_RSA_WITH_SEED_CBC_SHA SEED-SHA TLS_DH_DSS_WITH_SEED_CBC_SHA Not implemented. TLS_DH_RSA_WITH_SEED_CBC_SHA Not implemented. TLS_DHE_DSS_WITH_SEED_CBC_SHA DHE-DSS-SEED-SHA TLS_DHE_RSA_WITH_SEED_CBC_SHA DHE-RSA-SEED-SHA TLS_DH_anon_WITH_SEED_CBC_SHA ADH-SEED-SHA  

Additional Export 1024 and other cipher suites

Note: these ciphers can also be used in SSL v3.

TLS_RSA_EXPORT1024_WITH_DES_CBC_SHA EXP1024-DES-CBC-SHA TLS_RSA_EXPORT1024_WITH_RC4_56_SHA EXP1024-RC4-SHA TLS_DHE_DSS_EXPORT1024_WITH_DES_CBC_SHA EXP1024-DHE-DSS-DES-CBC-SHA TLS_DHE_DSS_EXPORT1024_WITH_RC4_56_SHA EXP1024-DHE-DSS-RC4-SHA TLS_DHE_DSS_WITH_RC4_128_SHA DHE-DSS-RC4-SHA  

SSL v2.0 cipher suites.

SSL_CK_RC4_128_WITH_MD5 RC4-MD5 SSL_CK_RC4_128_EXPORT40_WITH_MD5 EXP-RC4-MD5 SSL_CK_RC2_128_CBC_WITH_MD5 RC2-MD5 SSL_CK_RC2_128_CBC_EXPORT40_WITH_MD5 EXP-RC2-MD5 SSL_CK_IDEA_128_CBC_WITH_MD5 IDEA-CBC-MD5 SSL_CK_DES_64_CBC_WITH_MD5 DES-CBC-MD5 SSL_CK_DES_192_EDE3_CBC_WITH_MD5 DES-CBC3-MD5  

NOTES

The non-ephemeral DH modes are currently unimplemented in OpenSSL because there is no support for DH certificates.

Some compiled versions of OpenSSL may not include all the ciphers listed here because some ciphers were excluded at compile time.  

EXAMPLES

Verbose listing of all OpenSSL ciphers including NULL ciphers:

openssl ciphers -v ALL:eNULL

Include all ciphers except NULL and anonymous DH then sort by strength:

openssl ciphers -v ALL:!ADH:@STRENGTH

Include only 3DES ciphers and then place RSA ciphers last:

openssl ciphers -v 3DES:+RSA

Include all RC4 ciphers but leave out those without authentication:

openssl ciphers -v RC4:!COMPLEMENTOFDEFAULT

Include all chiphers with RSA authentication but leave out ciphers without encryption.

openssl ciphers -v RSA:!COMPLEMENTOFALL  

SEE ALSO

s_client(1), s_server(1), ssl(3)  

HISTORY

The COMPLENTOFALL and COMPLEMENTOFDEFAULT selection options were added in version 0.9.7.


 

Index

NAME
SYNOPSIS
DESCRIPTION
COMMAND OPTIONS
CIPHER LIST FORMAT
CIPHER STRINGS
CIPHER SUITE NAMES
SSL v3.0 cipher suites.
TLS v1.0 cipher suites.
AES ciphersuites from RFC3268, extending TLS v1.0
Camellia ciphersuites from RFC4132, extending TLS v1.0
SEED ciphersuites from RFC4162, extending TLS v1.0
Additional Export 1024 and other cipher suites
SSL v2.0 cipher suites.
NOTES
EXAMPLES
SEE ALSO
HISTORY

This document was created by man2html, using the manual pages.
 
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