ciphers.pod revision 59191
1=pod 2 3=head1 NAME 4 5ciphers - SSL cipher display and cipher list tool. 6 7=head1 SYNOPSIS 8 9B<openssl> B<ciphers> 10[B<-v>] 11[B<-ssl2>] 12[B<-ssl3>] 13[B<-tls1>] 14[B<cipherlist>] 15 16=head1 DESCRIPTION 17 18The B<cipherlist> command converts OpenSSL cipher lists into ordered 19SSL cipher preference lists. It can be used as a test tool to determine 20the appropriate cipherlist. 21 22=head1 COMMAND OPTIONS 23 24=over 4 25 26=item B<-v> 27 28verbose option. List ciphers with a complete description of the authentication, 29key exchange, encryption and mac algorithms used along with any key size 30restrictions and whether the algorithm is classed as an "export" cipher. 31 32=item B<-ssl3> 33 34only include SSL v3 ciphers. 35 36=item B<-ssl2> 37 38only include SSL v2 ciphers. 39 40=item B<-tls1> 41 42only include TLS v1 ciphers. 43 44=item B<-h>, B<-?> 45 46print a brief usage message. 47 48=item B<cipherlist> 49 50a cipher list to convert to a cipher preference list. If it is not included 51then the default cipher list will be used. The format is described below. 52 53=back 54 55=head1 CIPHER LIST FORMAT 56 57The cipher list consists of one or more I<cipher strings> separated by colons. 58Commas or spaces are also acceptable separators but colons are normally used. 59 60The actual cipher string can take several different forms. 61 62It can consist of a single cipher suite such as B<RC4-SHA>. 63 64It can represent a list of cipher suites containing a certain algorithm, or 65cipher suites of a certain type. For example B<SHA1> represents all ciphers 66suites using the digest algorithm SHA1 and B<SSLv3> represents all SSL v3 67algorithms. 68 69Lists of cipher suites can be combined in a single cipher string using the 70B<+> character. This is used as a logical B<and> operation. For example 71B<SHA1+DES> represents all cipher suites containing the SHA1 B<and> the DES 72algorithms. 73 74Each cipher string can be optionally preceded by the characters B<!>, 75B<-> or B<+>. 76 77If B<!> is used then the ciphers are permanently deleted from the list. 78The ciphers deleted can never reappear in the list even if they are 79explicitly stated. 80 81If B<-> is used then the ciphers are deleted from the list, but some or 82all of the ciphers can be added again by later options. 83 84If B<+> is used then the ciphers are moved to the end of the list. This 85option doesn't add any new ciphers it just moves matching existing ones. 86 87If none of these characters is present then the string is just interpreted 88as a list of ciphers to be appended to the current preference list. If the 89list includes any ciphers already present they will be ignored: that is they 90will not moved to the end of the list. 91 92Additionally the cipher string B<@STRENGTH> can be used at any point to sort 93the current cipher list in order of encryption algorithm key length. 94 95=head1 CIPHER STRINGS 96 97The following is a list of all permitted cipher strings and their meanings. 98 99=over 4 100 101=item B<DEFAULT> 102 103the default cipher list. This is determined at compile time and is normally 104B<ALL:!ADH:RC4+RSA:+SSLv2:@STRENGTH>. This must be the first cipher string 105specified. 106 107=item B<ALL> 108 109all ciphers suites except the B<eNULL> ciphers which must be explicitly enabled. 110 111=item B<HIGH> 112 113"high" encryption cipher suites. This currently means those with key lengths larger 114than 128 bits. 115 116=item B<MEDIUM> 117 118"medium" encryption cipher suites, currently those using 128 bit encryption. 119 120=item B<LOW> 121 122"low" encryption cipher suites, currently those using 64 or 56 bit encryption algorithms 123but excluding export cipher suites. 124 125=item B<EXP>, B<EXPORT> 126 127export encryption algorithms. Including 40 and 56 bits algorithms. 128 129=item B<EXPORT40> 130 13140 bit export encryption algorithms 132 133=item B<EXPORT56> 134 13556 bit export encryption algorithms. 136 137=item B<eNULL>, B<NULL> 138 139the "NULL" ciphers that is those offering no encryption. Because these offer no 140encryption at all and are a security risk they are disabled unless explicitly 141included. 142 143=item B<aNULL> 144 145the cipher suites offering no authentication. This is currently the anonymous 146DH algorithms. These cipher suites are vulnerable to a "man in the middle" 147attack and so their use is normally discouraged. 148 149=item B<kRSA>, B<RSA> 150 151cipher suites using RSA key exchange. 152 153=item B<kEDH> 154 155cipher suites using ephemeral DH key agreement. 156 157=item B<kDHr>, B<kDHd> 158 159cipher suites using DH key agreement and DH certificates signed by CAs with RSA 160and DSS keys respectively. Not implemented. 161 162=item B<aRSA> 163 164cipher suites using RSA authentication, i.e. the certificates carry RSA keys. 165 166=item B<aDSS>, B<DSS> 167 168cipher suites using DSS authentication, i.e. the certificates carry DSS keys. 169 170=item B<aDH> 171 172cipher suites effectively using DH authentication, i.e. the certificates carry 173DH keys. Not implemented. 174 175=item B<kFZA>, B<aFZA>, B<eFZA>, B<FZA> 176 177ciphers suites using FORTEZZA key exchange, authentication, encryption or all 178FORTEZZA algorithms. Not implemented. 179 180=item B<TLSv1>, B<SSLv3>, B<SSLv2> 181 182TLS v1.0, SSL v3.0 or SSL v2.0 cipher suites respectively. 183 184=item B<DH> 185 186cipher suites using DH, including anonymous DH. 187 188=item B<ADH> 189 190anonymous DH cipher suites. 191 192=item B<3DES> 193 194cipher suites using triple DES. 195 196=item B<DES> 197 198cipher suites using DES (not triple DES). 199 200=item B<RC4> 201 202cipher suites using RC4. 203 204=item B<RC2> 205 206cipher suites using RC2. 207 208=item B<IDEA> 209 210cipher suites using IDEA. 211 212=item B<MD5> 213 214cipher suites using MD5. 215 216=item B<SHA1>, B<SHA> 217 218cipher suites using SHA1. 219 220=back 221 222=head1 CIPHER SUITE NAMES 223 224The following lists give the SSL or TLS cipher suites names from the 225relevant specification and their OpenSSL equivalents. 226 227=head2 SSL v3.0 cipher suites. 228 229 SSL_RSA_WITH_NULL_MD5 NULL-MD5 230 SSL_RSA_WITH_NULL_SHA NULL-SHA 231 SSL_RSA_EXPORT_WITH_RC4_40_MD5 EXP-RC4-MD5 232 SSL_RSA_WITH_RC4_128_MD5 RC4-MD5 233 SSL_RSA_WITH_RC4_128_SHA RC4-SHA 234 SSL_RSA_EXPORT_WITH_RC2_CBC_40_MD5 EXP-RC2-CBC-MD5 235 SSL_RSA_WITH_IDEA_CBC_SHA IDEA-CBC-SHA 236 SSL_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-DES-CBC-SHA 237 SSL_RSA_WITH_DES_CBC_SHA DES-CBC-SHA 238 SSL_RSA_WITH_3DES_EDE_CBC_SHA DES-CBC3-SHA 239 240 SSL_DH_DSS_EXPORT_WITH_DES40_CBC_SHA Not implemented. 241 SSL_DH_DSS_WITH_DES_CBC_SHA Not implemented. 242 SSL_DH_DSS_WITH_3DES_EDE_CBC_SHA Not implemented. 243 SSL_DH_RSA_EXPORT_WITH_DES40_CBC_SHA Not implemented. 244 SSL_DH_RSA_WITH_DES_CBC_SHA Not implemented. 245 SSL_DH_RSA_WITH_3DES_EDE_CBC_SHA Not implemented. 246 SSL_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-DSS-DES-CBC-SHA 247 SSL_DHE_DSS_WITH_DES_CBC_SHA EDH-DSS-CBC-SHA 248 SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA EDH-DSS-DES-CBC3-SHA 249 SSL_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-RSA-DES-CBC-SHA 250 SSL_DHE_RSA_WITH_DES_CBC_SHA EDH-RSA-DES-CBC-SHA 251 SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA EDH-RSA-DES-CBC3-SHA 252 253 SSL_DH_anon_EXPORT_WITH_RC4_40_MD5 EXP-ADH-RC4-MD5 254 SSL_DH_anon_WITH_RC4_128_MD5 ADH-RC4-MD5 255 SSL_DH_anon_EXPORT_WITH_DES40_CBC_SHA EXP-ADH-DES-CBC-SHA 256 SSL_DH_anon_WITH_DES_CBC_SHA ADH-DES-CBC-SHA 257 SSL_DH_anon_WITH_3DES_EDE_CBC_SHA ADH-DES-CBC3-SHA 258 259 SSL_FORTEZZA_KEA_WITH_NULL_SHA Not implemented. 260 SSL_FORTEZZA_KEA_WITH_FORTEZZA_CBC_SHA Not implemented. 261 SSL_FORTEZZA_KEA_WITH_RC4_128_SHA Not implemented. 262 263=head2 TLS v1.0 cipher suites. 264 265 TLS_RSA_WITH_NULL_MD5 NULL-MD5 266 TLS_RSA_WITH_NULL_SHA NULL-SHA 267 TLS_RSA_EXPORT_WITH_RC4_40_MD5 EXP-RC4-MD5 268 TLS_RSA_WITH_RC4_128_MD5 RC4-MD5 269 TLS_RSA_WITH_RC4_128_SHA RC4-SHA 270 TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 EXP-RC2-CBC-MD5 271 TLS_RSA_WITH_IDEA_CBC_SHA IDEA-CBC-SHA 272 TLS_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-DES-CBC-SHA 273 TLS_RSA_WITH_DES_CBC_SHA DES-CBC-SHA 274 TLS_RSA_WITH_3DES_EDE_CBC_SHA DES-CBC3-SHA 275 276 TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA Not implemented. 277 TLS_DH_DSS_WITH_DES_CBC_SHA Not implemented. 278 TLS_DH_DSS_WITH_3DES_EDE_CBC_SHA Not implemented. 279 TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA Not implemented. 280 TLS_DH_RSA_WITH_DES_CBC_SHA Not implemented. 281 TLS_DH_RSA_WITH_3DES_EDE_CBC_SHA Not implemented. 282 TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-DSS-DES-CBC-SHA 283 TLS_DHE_DSS_WITH_DES_CBC_SHA EDH-DSS-CBC-SHA 284 TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA EDH-DSS-DES-CBC3-SHA 285 TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA EXP-EDH-RSA-DES-CBC-SHA 286 TLS_DHE_RSA_WITH_DES_CBC_SHA EDH-RSA-DES-CBC-SHA 287 TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA EDH-RSA-DES-CBC3-SHA 288 289 TLS_DH_anon_EXPORT_WITH_RC4_40_MD5 EXP-ADH-RC4-MD5 290 TLS_DH_anon_WITH_RC4_128_MD5 ADH-RC4-MD5 291 TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA EXP-ADH-DES-CBC-SHA 292 TLS_DH_anon_WITH_DES_CBC_SHA ADH-DES-CBC-SHA 293 TLS_DH_anon_WITH_3DES_EDE_CBC_SHA ADH-DES-CBC3-SHA 294 295=head2 Additional Export 1024 and other cipher suites 296 297Note: these ciphers can also be used in SSL v3. 298 299 TLS_RSA_EXPORT1024_WITH_DES_CBC_SHA EXP1024-DES-CBC-SHA 300 TLS_RSA_EXPORT1024_WITH_RC4_56_SHA EXP1024-RC4-SHA 301 TLS_DHE_DSS_EXPORT1024_WITH_DES_CBC_SHA EXP1024-DHE-DSS-DES-CBC-SHA 302 TLS_DHE_DSS_EXPORT1024_WITH_RC4_56_SHA EXP1024-DHE-DSS-RC4-SHA 303 TLS_DHE_DSS_WITH_RC4_128_SHA DHE-DSS-RC4-SHA 304 305=head2 SSL v2.0 cipher suites. 306 307 SSL_CK_RC4_128_WITH_MD5 RC4-MD5 308 SSL_CK_RC4_128_EXPORT40_WITH_MD5 EXP-RC4-MD5 309 SSL_CK_RC2_128_CBC_WITH_MD5 RC2-MD5 310 SSL_CK_RC2_128_CBC_EXPORT40_WITH_MD5 EXP-RC2-MD5 311 SSL_CK_IDEA_128_CBC_WITH_MD5 IDEA-CBC-MD5 312 SSL_CK_DES_64_CBC_WITH_MD5 DES-CBC-MD5 313 SSL_CK_DES_192_EDE3_CBC_WITH_MD5 DES-CBC3-MD5 314 315=head1 NOTES 316 317The non-ephemeral DH modes are currently unimplemented in OpenSSL 318because there is no support for DH certificates. 319 320Some compiled versions of OpenSSL may not include all the ciphers 321listed here because some ciphers were excluded at compile time. 322 323=head1 EXAMPLES 324 325Verbose listing of all OpenSSL ciphers including NULL ciphers: 326 327 openssl ciphers -v 'ALL:eNULL' 328 329Include all ciphers except NULL and anonymous DH then sort by 330strength: 331 332 openssl ciphers -v 'ALL:!ADH:@STRENGTH' 333 334Include only 3DES ciphers and then place RSA ciphers last: 335 336 openssl ciphers -v '3DES:+RSA' 337 338=head1 SEE ALSO 339 340L<s_client(1)|s_client(1)>, L<s_server(1)|s_server(1)>, L<ssl(3)|ssl(3)> 341 342=cut 343