3 This engine provides implementation of Russian cryptography standard.
4 This is also an example of adding new cryptoalgorithms into OpenSSL
5 without changing its core. If OpenSSL is compiled with dynamic engine
6 support, new algorithms can be added even without recompilation of
7 OpenSSL and applications which use it.
11 GOST R 34.10-2001 and GOST R 34.10-2012 - digital signature algorithms.
12 Also support key exchange based on public keys. See RFC 4357 for
13 details of VKO key exchange algorithm. These algorithms use
14 256 bit private keys. Public keys are 1024 bit for 94 and 512 bit for
15 2001 (which is elliptic-curve based). Key exchange algorithms
16 (VKO R 34.10) are supported on these keys too.
18 GOST R 34.11-2012 Message digest algorithm. 256- and 512-bit hash values.
20 GOST 28147-89 - Symmetric cipher with 256-bit key. Various modes are
21 defined in the standard, but only CFB and CNT modes are implemented
22 in the engine. To make statistical analysis more difficult, key
23 meshing is supported (see RFC 4357).
25 GOST 28147-89 MAC mode. Message authentication code. While most MAC
26 algorithms out there are based on hash functions using HMAC
27 algorithm, this algoritm is based on symmetric cipher.
28 It has 256-bit symmetric key and only 32 bits of MAC value
29 (while HMAC has same key size and value size).
31 Really, this algorithm supports from 8 to 64 bits of the MAC value
33 It is implemented as combination of EVP_PKEY type and EVP_MD type.
35 GOST R 34.13–2015 - Symmetric cypher Grasshopper ("Kuznechik")
37 USAGE OF THESE ALGORITHMS
39 This engine is designed to allow usage of this algorithms in the
40 high-level openssl functions, such as PKI, S/MIME and TLS.
42 See RFC 4490 for S/MIME with GOST algorithms and RFC 4491 for PKI.
43 TLS support is implemented according IETF
44 draft-chudov-cryptopro-cptls-03.txt and is compatible with
45 CryptoPro CSP 3.0 and 3.6 as well as with MagPro CSP.
46 GOST ciphersuites implemented in CryptoPro CSP 2.0 are not supported
47 because they use ciphersuite numbers used now by AES ciphersuites.
49 To use the engine you have to load it via openssl configuration
50 file. Applications should read openssl configuration file or provide
51 their own means to load engines. Also, applications which operate with
52 private keys, should use generic EVP_PKEY API instead of using RSA or
53 other algorithm-specific API.
57 Configuration file should include following statement in the global
58 section, i.e. before first bracketed section header (see config(5) for details)
60 openssl_conf = openssl_def
62 where openssl_def is name of the section in configuration file which
63 describes global defaults.
65 This section should contain following statement:
68 engines = engine_section
70 which points to the section which describes list of the engines to be
71 loaded. This section should contain:
76 And section which describes configuration of the engine should contain
80 dynamic_path = /usr/lib/ssl/engines/libgost.so
81 default_algorithms = ALL
82 CRYPT_PARAMS = id-Gost28147-89-CryptoPro-A-ParamSet
84 If you want use unmask private key format, you must add:
88 Where engine_id parameter specifies name of engine (should be "gost").
89 dynamic_path is a location of the loadable shared library implementing the
90 engine. If the engine is compiled statically or is located in the OpenSSL
91 engines directory, this line can be omitted.
92 default_algorithms parameter specifies that all algorithms, provided by
93 engine, should be used.
95 The CRYPT_PARAMS parameter is engine-specific. It allows the user to choose
96 between different parameter sets of symmetric cipher algorithm. RFC 4357
97 specifies several parameters for the GOST 28147-89 algorithm, but OpenSSL
98 doesn't provide user interface to choose one when encrypting. So use engine
99 configuration parameter instead.
101 Value of this parameter can be either short name, defined in OpenSSL
102 obj_dat.h header file or numeric representation of OID, defined in RFC
105 USAGE WITH COMMAND LINE openssl UTILITY
107 1. Generation of private key
109 openssl genpkey -algorithm gost2001 -pkeyopt paramset:A -out seckey.pem
111 Use -algorithm option to specify algorithm.
112 Use -pkeyopt option to pass paramset to algorithm. The following paramsets
114 gost94: 0,A,B,C,D,XA,XB,XC
115 gost2001: 0,A,B,C,XA,XB
116 You can also use numeric representation of OID as to destinate
119 Paramsets starting with X are intended to use for key exchange keys.
120 Paramsets without X are for digital signature keys.
122 Paramset for both algorithms 0 is the test paramset which should be used
123 only for test purposes.
125 There are no algorithm-specific things with generation of certificate
126 request once you have a private key.
128 2. Generation of certificate request along with private/public keypar
130 openssl req -newkey gost2001 -pkeyopt paramset:A
132 Syntax of -pkeyopt parameter is identical with genpkey command.
134 You can also use oldstyle syntax -newkey gost2001:paramfile, but in
135 this case you should create parameter file first.
137 It can be created with
139 openssl genpkey -genparam -algorithm gost2001 -pkeyopt paramset:A\
144 If you want to send encrypted mail using GOST algorithms, don't forget
145 to specify -gost89 as encryption algorithm for OpenSSL smime command.
146 While OpenSSL is clever enough to find out that GOST R 34.11-94 digest
147 must be used for digital signing with GOST private key, it have no way
148 to derive symmetric encryption algorithm from key exchange keys.
152 OpenSSL supports all four ciphersuites defined in the IETF draft.
153 Once you've loaded GOST key and certificate into your TLS server,
154 ciphersuites which use GOST 28147-89 encryption are enabled.
156 Ciphersuites with NULL encryption should be enabled explicitely if
159 GOST2001-GOST89-GOST89 Uses GOST R 34.10-2001 for auth and key exchange
160 GOST 28147-89 for encryption and GOST 28147-89 MAC
161 GOST94-GOST89-GOST89 Uses GOST R 34.10-94 for auth and key exchange
162 GOST 28147-89 for encryption and GOST 28147-89 MAC
163 GOST2001-NULL-GOST94 Uses GOST R 34.10-2001 for auth and key exchange,
164 no encryption and HMAC, based on GOST R 34.11-94
165 GOST94-NULL-GOST94 Uses GOST R 34.10-94 for auth and key exchange,
166 no encryption and HMAC, based on GOST R 34.11-94
168 Gost 94 and gost 2001 keys can be used simultaneously in the TLS server.
169 RSA, DSA and EC keys can be used simultaneously with GOST keys, if
170 server implementation supports loading more than two private
171 key/certificate pairs. In this case ciphersuites which use any of loaded
172 keys would be supported and clients can negotiate ones they wish.
174 This allows creation of TLS servers which use GOST ciphersuites for
175 Russian clients and RSA/DSA ciphersuites for foreign clients.
177 5. Calculation of digests and symmetric encryption
178 OpenSSL provides specific commands (like sha1, aes etc) for calculation
179 of digests and symmetric encryption. Since such commands cannot be
180 added dynamically, no such commands are provided for GOST algorithms.
181 Use generic commands 'dgst' and 'enc'.
183 Calculation of GOST R 34.11-94 message digest
185 openssl dgst -md_gost94 datafile
187 Note that GOST R 34.11-94 specifies that digest value should be
188 interpreted as little-endian number, but OpenSSL outputs just hex dump
191 So, to obtain correct digest value, such as produced by gostsum utility
192 included in the engine distribution, bytes of output should be
195 Calculation of HMAC based on GOST R 34.11-94
197 openssl dgst -md_gost94 -mac hmac -macopt key:<32 bytes of key> datafile
199 (or use hexkey if key contain NUL bytes)
200 Calculation of GOST 28147 MAC
202 openssl dgst -mac gost-mac -macopt key:<32 bytes of key> datafile
204 Note absence of an option that specifies digest algorithm. gost-mac
205 algorithm supports only one digest (which is actually part of
206 implementation of this mac) and OpenSSL is clever enough to find out
209 Following mac options are supported:
211 key:(32 bytes of key)
213 hexkey:(64 hexadecimal digits of key)
215 Engine support calculation of mac with size different from default 32
216 bits. You can set mac size to any value from 1 to 8 bytes using
218 -sigopt size:(number from 1 to 8 - mac size in bytes)
220 (dgst command uses different EVP_PKEY_CTX for initialization and for
221 finalization of MAC. Option of first are set via -macopt, and for
222 second via -sigopt. Key should be set during initialization and size
223 during finalization. If you use API functions
224 EVP_DigestSignInit/EVP_DigestSignFinal, you can set both options at
227 Encryption with GOST 28147 CFB mode
228 openssl enc -gost89 -out encrypted-file -in plain-text-file -k <passphrase>
229 Encryption with GOST 28147 CNT mode
230 openssl enc -gost89-cnt -out encrypted-file -in plain-text-file -k <passphrase>
231 Encryption with GOST 28147 CBC mode
232 openssl enc -gost89-cbc -out encrypted-file -in plain-text-file -k <passphrase>
234 6. Encrypting private keys and PKCS12
236 To produce PKCS12 files compatible with MagPro CSP, you need to use
237 GOST algorithm for encryption of PKCS12 file and also GOST R 34.11-94
238 hash to derive key from password.
240 openssl pksc12 -export -inkey gost.pem -in gost_cert.pem -keypbe gost89\
241 -certpbe gost89 -macalg md_gost94
243 7. Testing speed of symmetric ciphers.
245 To test performance of GOST symmetric ciphers you should use -evp switch
246 of the openssl speed command. Engine-provided ciphers couldn't be
247 accessed by cipher-specific functions, only via generic evp interface
249 openssl speed -evp gost89
250 openssl speed -evp gost89-cnt
251 openssl speed -evp gost89-cbc
254 PROGRAMMING INTERFACES DETAILS
256 Applications never should access engine directly. They only use provided
257 EVP_PKEY API. But there are some details, which should be taken into
260 EVP provides two kinds of API for key exchange:
262 1. EVP_PKEY_encrypt/EVP_PKEY_decrypt functions, intended to use with
263 RSA-like public key encryption algorithms
265 2. EVP_PKEY_derive, intended to use with Diffie-Hellman-like shared key
266 computing algorithms.
268 Although VKO R 34.10 algorithms, described in the RFC 4357 are
269 definitely second case, engine provides BOTH API for GOST R 34.10 keys.
271 EVP_PKEY_derive just invokes appropriate VKO algorithm and computes
272 256 bit shared key. VKO R 34.10-2001 requires 64 bits of random user key
273 material (UKM). This UKM should be transmitted to other party, so it is
274 not generated inside derive function.
276 It should be set by EVP_PKEY_CTX_ctrl function using
277 EVP_PKEY_CTRL_SET_IV command after call of EVP_PKEY_derive_init, but
278 before EVP_PKEY_derive.
279 unsigned char ukm[8];
281 EVP_PKEY_CTX_ctrl(ctx, -1, EVP_PKEY_OP_DERIVE, 8, ukm)
283 EVP_PKEY_encrypt encrypts provided session key with VKO shared key and
284 packs it into GOST key transport structure, described in the RFC 4490.
286 It typically uses ephemeral key pair to compute shared key and packs its
287 public part along with encrypted key. So, for most cases use of
288 EVP_PKEY_encrypt/EVP_PKEY_decrypt with GOST keys is almost same as with
291 However, if peerkey field in the EVP_PKEY_CTX structure is set (using
292 EVP_PKEY_derive_set_peerkey function) to EVP_PKEY structure which has private
293 key and uses same parameters as the public key from which this EVP_PKEY_CTX is
294 created, EVP_PKEY_encrypt will use this private key to compute shared key and
295 set ephemeral key in the GOST_key_transport structure to NULL. In this case
296 pkey and peerkey fields in the EVP_PKEY_CTX are used upside-down.
298 If EVP_PKEY_decrypt encounters GOST_key_transport structure with NULL
299 public key field, it tries to use peerkey field from the context to
300 compute shared key. In this case peerkey field should really contain
303 Encrypt operation supports EVP_PKEY_CTRL_SET_IV operation as well.
304 It can be used when some specific restriction on UKM are imposed by
305 higher level protocol. For instance, description of GOST ciphersuites
306 requires UKM to be derived from shared secret.
308 If UKM is not set by this control command, encrypt operation would
312 This sources include implementation of GOST 28147-89 and GOST R 34.11-94
313 which are completely indepentent from OpenSSL and can be used separately
314 (files gost89.c, gost89.h, gosthash.c, gosthash.h) Utility gostsum (file
315 gostsum.c) is provided as example of such separate usage. This is
316 program, simular to md5sum and sha1sum utilities, but calculates GOST R
319 Makefile doesn't include rule for compiling gostsum.
322 $(CC) -o gostsum gostsum.c gost89.c gosthash.c
323 where $(CC) is name of your C compiler.
325 Implementations of GOST R 34.10-xx, including VKO algorithms heavily
326 depends on OpenSSL BIGNUM and Elliptic Curve libraries.