class OpenSSL::PKey::DSA
DSA
, the Digital Signature Algorithm, is specified in NIST’s FIPS 186-3. It is an asymmetric public key algorithm that may be used similar to e.g. RSA
.
Public Class Methods
Creates a new DSA
instance by generating a private/public key pair from scratch.
See also OpenSSL::PKey.generate_parameters
and OpenSSL::PKey.generate_key
.
size
-
The desired key size in bits.
# File openssl/lib/openssl/pkey.rb, line 169 def generate(size, &blk) # FIPS 186-4 specifies four (L,N) pairs: (1024,160), (2048,224), # (2048,256), and (3072,256). # # q size is derived here with compatibility with # DSA_generator_parameters_ex() which previous versions of ruby/openssl # used to call. qsize = size >= 2048 ? 256 : 160 dsaparams = OpenSSL::PKey.generate_parameters("DSA", { "dsa_paramgen_bits" => size, "dsa_paramgen_q_bits" => qsize, }, &blk) OpenSSL::PKey.generate_key(dsaparams) end
Creates a new DSA
instance by reading an existing key from string.
If called without arguments, creates a new instance with no key components set. They can be set individually by set_pqg
and set_key
.
If called with a String, tries to parse as DER or PEM encoding of a DSA key. See also OpenSSL::PKey.read
which can parse keys of any kinds.
If called with a number, generates random parameters and a key pair. This form works as an alias of DSA.generate
.
string
-
A String that contains a DER or PEM encoded key.
pass
-
A String that contains an optional password.
size
-
See
DSA.generate
.
Examples:
p OpenSSL::PKey::DSA.new(1024) #=> #<OpenSSL::PKey::DSA:0x000055a8d6025bf0 oid=DSA> p OpenSSL::PKey::DSA.new(File.read('dsa.pem')) #=> #<OpenSSL::PKey::DSA:0x000055555d6b8110 oid=DSA> p OpenSSL::PKey::DSA.new(File.read('dsa.pem'), 'mypassword') #=> #<OpenSSL::PKey::DSA:0x0000556f973c40b8 oid=DSA>
static VALUE ossl_dsa_initialize(int argc, VALUE *argv, VALUE self) { EVP_PKEY *pkey; DSA *dsa; BIO *in = NULL; VALUE arg, pass; int type; TypedData_Get_Struct(self, EVP_PKEY, &ossl_evp_pkey_type, pkey); if (pkey) rb_raise(rb_eTypeError, "pkey already initialized"); /* The DSA.new(size, generator) form is handled by lib/openssl/pkey.rb */ rb_scan_args(argc, argv, "02", &arg, &pass); if (argc == 0) { dsa = DSA_new(); if (!dsa) ossl_raise(eDSAError, "DSA_new"); goto legacy; } pass = ossl_pem_passwd_value(pass); arg = ossl_to_der_if_possible(arg); in = ossl_obj2bio(&arg); /* DER-encoded DSAPublicKey format isn't supported by the generic routine */ dsa = (DSA *)PEM_ASN1_read_bio((d2i_of_void *)d2i_DSAPublicKey, PEM_STRING_DSA_PUBLIC, in, NULL, NULL, NULL); if (dsa) goto legacy; OSSL_BIO_reset(in); pkey = ossl_pkey_read_generic(in, pass); BIO_free(in); if (!pkey) ossl_raise(eDSAError, "Neither PUB key nor PRIV key"); type = EVP_PKEY_base_id(pkey); if (type != EVP_PKEY_DSA) { EVP_PKEY_free(pkey); rb_raise(eDSAError, "incorrect pkey type: %s", OBJ_nid2sn(type)); } RTYPEDDATA_DATA(self) = pkey; return self; legacy: BIO_free(in); pkey = EVP_PKEY_new(); if (!pkey || EVP_PKEY_assign_DSA(pkey, dsa) != 1) { EVP_PKEY_free(pkey); DSA_free(dsa); ossl_raise(eDSAError, "EVP_PKEY_assign_DSA"); } RTYPEDDATA_DATA(self) = pkey; return self; }
Public Instance Methods
Serializes a private or public key to a PEM-encoding.
- When the key contains public components only
-
Serializes it into an X.509 SubjectPublicKeyInfo. The parameters cipher and password are ignored.
A PEM-encoded key will look like:
-----BEGIN PUBLIC KEY----- [...] -----END PUBLIC KEY-----
Consider using
public_to_pem
instead. This serializes the key into an X.509 SubjectPublicKeyInfo regardless of whether it is a public key or a private key. - When the key contains private components, and no parameters are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey.
A PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- [...] -----END DSA PRIVATE KEY-----
- When the key contains private components, and cipher and password are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey and encrypts it in OpenSSL’s traditional PEM encryption format. cipher must be a cipher name understood by
OpenSSL::Cipher.new
or an instance ofOpenSSL::Cipher
.An encrypted PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- Proc-Type: 4,ENCRYPTED DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0 [...] -----END DSA PRIVATE KEY-----
Note that this format uses MD5 to derive the encryption key, and hence will not be available on FIPS-compliant systems.
This method is kept for compatibility. This should only be used when the traditional, non-standard OpenSSL format is required.
Consider using public_to_pem
(X.509 SubjectPublicKeyInfo) or private_to_pem
(PKCS #8 PrivateKeyInfo or EncryptedPrivateKeyInfo) instead.
static VALUE ossl_dsa_export(int argc, VALUE *argv, VALUE self) { OSSL_3_const DSA *dsa; GetDSA(self, dsa); if (DSA_HAS_PRIVATE(dsa)) return ossl_pkey_export_traditional(argc, argv, self, 0); else return ossl_pkey_export_spki(self, 0); }
static VALUE ossl_dsa_initialize_copy(VALUE self, VALUE other) { EVP_PKEY *pkey; DSA *dsa, *dsa_new; TypedData_Get_Struct(self, EVP_PKEY, &ossl_evp_pkey_type, pkey); if (pkey) rb_raise(rb_eTypeError, "pkey already initialized"); GetDSA(other, dsa); dsa_new = (DSA *)ASN1_dup((i2d_of_void *)i2d_DSAPrivateKey, (d2i_of_void *)d2i_DSAPrivateKey, (char *)dsa); if (!dsa_new) ossl_raise(eDSAError, "ASN1_dup"); pkey = EVP_PKEY_new(); if (!pkey || EVP_PKEY_assign_DSA(pkey, dsa_new) != 1) { EVP_PKEY_free(pkey); DSA_free(dsa_new); ossl_raise(eDSAError, "EVP_PKEY_assign_DSA"); } RTYPEDDATA_DATA(self) = pkey; return self; }
Stores all parameters of key to the hash INSECURE: PRIVATE INFORMATIONS CAN LEAK OUT!!! Don’t use :-)) (I’s up to you)
static VALUE ossl_dsa_get_params(VALUE self) { OSSL_3_const DSA *dsa; VALUE hash; const BIGNUM *p, *q, *g, *pub_key, *priv_key; GetDSA(self, dsa); DSA_get0_pqg(dsa, &p, &q, &g); DSA_get0_key(dsa, &pub_key, &priv_key); hash = rb_hash_new(); rb_hash_aset(hash, rb_str_new2("p"), ossl_bn_new(p)); rb_hash_aset(hash, rb_str_new2("q"), ossl_bn_new(q)); rb_hash_aset(hash, rb_str_new2("g"), ossl_bn_new(g)); rb_hash_aset(hash, rb_str_new2("pub_key"), ossl_bn_new(pub_key)); rb_hash_aset(hash, rb_str_new2("priv_key"), ossl_bn_new(priv_key)); return hash; }
Indicates whether this DSA
instance has a private key associated with it or not. The private key may be retrieved with DSA#private_key.
static VALUE ossl_dsa_is_private(VALUE self) { OSSL_3_const DSA *dsa; GetDSA(self, dsa); return DSA_PRIVATE(self, dsa) ? Qtrue : Qfalse; }
Indicates whether this DSA
instance has a public key associated with it or not. The public key may be retrieved with DSA#public_key
.
static VALUE ossl_dsa_is_public(VALUE self) { const DSA *dsa; const BIGNUM *bn; GetDSA(self, dsa); DSA_get0_key(dsa, &bn, NULL); return bn ? Qtrue : Qfalse; }
Returns a new DSA
instance that carries just the DSA parameters and the public key.
This method is provided for backwards compatibility. In most cases, there is no need to call this method.
For the purpose of serializing the public key, to PEM or DER encoding of X.509 SubjectPublicKeyInfo format, check PKey#public_to_pem
and PKey#public_to_der
.
# File openssl/lib/openssl/pkey.rb, line 153 def public_key OpenSSL::PKey.read(public_to_der) end
Sets pub_key and priv_key for the DSA
instance. priv_key may be nil
.
Sets p, q, g to the DSA
instance.
Computes and returns the DSA signature of string
, where string
is expected to be an already-computed message digest of the original input data. The signature is issued using the private key of this DSA
instance.
Deprecated in version 3.0. Consider using PKey::PKey#sign_raw
and PKey::PKey#verify_raw
instead.
string
-
A message digest of the original input data to be signed.
Example:
dsa = OpenSSL::PKey::DSA.new(2048) doc = "Sign me" digest = OpenSSL::Digest.digest('SHA1', doc) # With legacy #syssign and #sysverify: sig = dsa.syssign(digest) p dsa.sysverify(digest, sig) #=> true # With #sign_raw and #verify_raw: sig = dsa.sign_raw(nil, digest) p dsa.verify_raw(nil, sig, digest) #=> true
# File openssl/lib/openssl/pkey.rb, line 220 def syssign(string) q or raise OpenSSL::PKey::DSAError, "incomplete DSA" private? or raise OpenSSL::PKey::DSAError, "Private DSA key needed!" begin sign_raw(nil, string) rescue OpenSSL::PKey::PKeyError raise OpenSSL::PKey::DSAError, $!.message end end
Verifies whether the signature is valid given the message digest input. It does so by validating sig
using the public key of this DSA
instance.
Deprecated in version 3.0. Consider using PKey::PKey#sign_raw
and PKey::PKey#verify_raw
instead.
digest
-
A message digest of the original input data to be signed.
sig
-
A DSA signature value.
# File openssl/lib/openssl/pkey.rb, line 243 def sysverify(digest, sig) verify_raw(nil, sig, digest) rescue OpenSSL::PKey::PKeyError raise OpenSSL::PKey::DSAError, $!.message end
Serializes a private or public key to a DER-encoding.
See to_pem
for details.
This method is kept for compatibility. This should only be used when the traditional, non-standard OpenSSL format is required.
Consider using public_to_der
or private_to_der
instead.
static VALUE ossl_dsa_to_der(VALUE self) { OSSL_3_const DSA *dsa; GetDSA(self, dsa); if (DSA_HAS_PRIVATE(dsa)) return ossl_pkey_export_traditional(0, NULL, self, 1); else return ossl_pkey_export_spki(self, 1); }
Serializes a private or public key to a PEM-encoding.
- When the key contains public components only
-
Serializes it into an X.509 SubjectPublicKeyInfo. The parameters cipher and password are ignored.
A PEM-encoded key will look like:
-----BEGIN PUBLIC KEY----- [...] -----END PUBLIC KEY-----
Consider using
public_to_pem
instead. This serializes the key into an X.509 SubjectPublicKeyInfo regardless of whether it is a public key or a private key. - When the key contains private components, and no parameters are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey.
A PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- [...] -----END DSA PRIVATE KEY-----
- When the key contains private components, and cipher and password are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey and encrypts it in OpenSSL’s traditional PEM encryption format. cipher must be a cipher name understood by
OpenSSL::Cipher.new
or an instance ofOpenSSL::Cipher
.An encrypted PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- Proc-Type: 4,ENCRYPTED DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0 [...] -----END DSA PRIVATE KEY-----
Note that this format uses MD5 to derive the encryption key, and hence will not be available on FIPS-compliant systems.
This method is kept for compatibility. This should only be used when the traditional, non-standard OpenSSL format is required.
Consider using public_to_pem
(X.509 SubjectPublicKeyInfo) or private_to_pem
(PKCS #8 PrivateKeyInfo or EncryptedPrivateKeyInfo) instead.
Serializes a private or public key to a PEM-encoding.
- When the key contains public components only
-
Serializes it into an X.509 SubjectPublicKeyInfo. The parameters cipher and password are ignored.
A PEM-encoded key will look like:
-----BEGIN PUBLIC KEY----- [...] -----END PUBLIC KEY-----
Consider using
public_to_pem
instead. This serializes the key into an X.509 SubjectPublicKeyInfo regardless of whether it is a public key or a private key. - When the key contains private components, and no parameters are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey.
A PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- [...] -----END DSA PRIVATE KEY-----
- When the key contains private components, and cipher and password are given
-
Serializes it into a traditional OpenSSL DSAPrivateKey and encrypts it in OpenSSL’s traditional PEM encryption format. cipher must be a cipher name understood by
OpenSSL::Cipher.new
or an instance ofOpenSSL::Cipher
.An encrypted PEM-encoded key will look like:
-----BEGIN DSA PRIVATE KEY----- Proc-Type: 4,ENCRYPTED DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0 [...] -----END DSA PRIVATE KEY-----
Note that this format uses MD5 to derive the encryption key, and hence will not be available on FIPS-compliant systems.
This method is kept for compatibility. This should only be used when the traditional, non-standard OpenSSL format is required.
Consider using public_to_pem
(X.509 SubjectPublicKeyInfo) or private_to_pem
(PKCS #8 PrivateKeyInfo or EncryptedPrivateKeyInfo) instead.