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.
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
ALL:!ADH:RC4+RSA:+SSLv2:@STRENGTH. This must be the
first cipher string specified.
ALL all ciphers suites except the eNULL ciphers which must
be explicitly enabled.
HIGH
"high" encryption cipher suites. This currently means
those with key lengths larger than 128 bits.
MEDIUM
"medium" encryption cipher suites, currently those
using 128 bit encryption.
LOW "low" encryption cipher suites, currently those using
64 or 56 bit encryption algorithms but excluding
export cipher suites.
export encryption algorithms. Including 40 and 56 bits
algorithms.
EXPORT40
40 bit export encryption algorithms
EXPORT56
56 bit export encryption algorithms.
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.
ADH anonymous DH cipher suites.
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.
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.
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_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
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_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'
SEE ALSO
s_client(1), s_server(1), ssl(3)
Man(1) output converted with
man2html