Class: OpenSSL::PKey::DSA

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, `PKey`
Instance Chain: self, `PKey`
Inherits:	OpenSSL::PKey::PKey `::Object` OpenSSL::PKey::PKey OpenSSL::PKey::DSA
Defined in:	ext/openssl/ossl_pkey_dsa.c

Overview

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.

Class Method Summary

.generate(size) ⇒ DSA

Creates a new DSA instance by generating a private/public key pair from scratch.
.new ⇒ DSA constructor

Creates a new DSA instance by reading an existing key from string.

`PKey` - Inherited

.new	Because PKey is an abstract class, actually calling this method explicitly will raise a NotImplementedError.

Instance Attribute Summary

#private? ⇒ Boolean readonly

Indicates whether this DSA instance has a private key associated with it or not.
#public? ⇒ Boolean readonly

Indicates whether this DSA instance has a public key associated with it or not.

Instance Method Summary

#export([cipher, password]) ⇒ String

Alias for #to_s.
#initialize_copy(other)
#params ⇒ Hash

Stores all parameters of key to the hash INSECURE: PRIVATE INFORMATIONS CAN LEAK OUT!!! Don’t use :-)) (I’s up to you).
#public_key ⇒ DSA

Returns a new DSA instance that carries just the public key information.
#set_key(pub_key, priv_key) ⇒ self

Sets pub_key and priv_key for the DSA instance.
#set_pqg(p, q, g) ⇒ self

Sets p, q, g to the DSA instance.
#syssign(string) ⇒ String

Computes and returns the DSA signature of string, where string is expected to be an already-computed message digest of the original input data.
#sysverify(digest, sig) ⇒ Boolean

Verifies whether the signature is valid given the message digest input.
#to_der ⇒ String

Encodes this DSA to its DER encoding.
#to_pem([cipher, password]) ⇒ String

Alias for #to_s.
#to_s([cipher, password]) ⇒ String (also: #export, #to_pem)

Encodes this DSA to its PEM encoding.
#to_text ⇒ String

Prints all parameters of key to buffer INSECURE: PRIVATE INFORMATIONS CAN LEAK OUT!!! Don’t use :-)) (I’s up to you).

`PKey` - Inherited

#sign	To sign the String data, digest, an instance of `::OpenSSL::Digest`, must be provided.
#verify	To verify the String signature, digest, an instance of `::OpenSSL::Digest`, must be provided to re-compute the message digest of the original data, also a String.

Constructor Details

.new ⇒ `DSA` .new(size) ⇒ `DSA` .new(string [, pass]) ⇒ `DSA`

Creates a new DSA instance by reading an existing key from string.

Parameters

size is an integer representing the desired key size.
string contains a DER or PEM encoded key.
pass is a string that contains an optional password.

Examples

DSA.new -> dsa
DSA.new(1024) -> dsa
DSA.new(File.read('dsa.pem')) -> dsa
DSA.new(File.read('dsa.pem'), 'mypassword') -> dsa

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 212


static VALUE
ossl_dsa_initialize(int argc, VALUE *argv, VALUE self)
{
    EVP_PKEY *pkey;
    DSA *dsa;
    BIO *in;
    VALUE arg, pass;

    GetPKey(self, pkey);
    if(rb_scan_args(argc, argv, "02", &arg, &pass) == 0) {
        dsa = DSA_new();
    }
    else if (RB_INTEGER_TYPE_P(arg)) {
	if (!(dsa = dsa_generate(NUM2INT(arg)))) {
	    ossl_raise(eDSAError, NULL);
	}
    }
    else {
	pass = ossl_pem_passwd_value(pass);
	arg = ossl_to_der_if_possible(arg);
	in = ossl_obj2bio(&arg);
	dsa = PEM_read_bio_DSAPrivateKey(in, NULL, ossl_pem_passwd_cb, (void *)pass);
	if (!dsa) {
	    OSSL_BIO_reset(in);
	    dsa = PEM_read_bio_DSA_PUBKEY(in, NULL, NULL, NULL);
	}
	if (!dsa) {
	    OSSL_BIO_reset(in);
	    dsa = d2i_DSAPrivateKey_bio(in, NULL);
	}
	if (!dsa) {
	    OSSL_BIO_reset(in);
	    dsa = d2i_DSA_PUBKEY_bio(in, NULL);
	}
	if (!dsa) {
	    OSSL_BIO_reset(in);
#define PEM_read_bio_DSAPublicKey(bp,x,cb,u) (DSA *)PEM_ASN1_read_bio( \
	(d2i_of_void *)d2i_DSAPublicKey, PEM_STRING_DSA_PUBLIC, (bp), (void **)(x), (cb), (u))
	    dsa = PEM_read_bio_DSAPublicKey(in, NULL, NULL, NULL);
#undef PEM_read_bio_DSAPublicKey
	}
	BIO_free(in);
	if (!dsa) {
	    ossl_clear_error();
	    ossl_raise(eDSAError, "Neither PUB key nor PRIV key");
	}
    }
    if (!EVP_PKEY_assign_DSA(pkey, dsa)) {
	DSA_free(dsa);
	ossl_raise(eDSAError, NULL);
    }

    return self;
}

Class Method Details

.generate(size) ⇒ `DSA`

Creates a new DSA instance by generating a private/public key pair from scratch.

Parameters

size is an integer representing the desired key size.

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 178


static VALUE
ossl_dsa_s_generate(VALUE klass, VALUE size)
{
    DSA *dsa = dsa_generate(NUM2INT(size)); /* err handled by dsa_instance */
    VALUE obj = dsa_instance(klass, dsa);

    if (obj == Qfalse) {
	DSA_free(dsa);
	ossl_raise(eDSAError, NULL);
    }

    return obj;
}

Instance Attribute Details

#private? ⇒ `Boolean` (readonly)

Indicates whether this DSA instance has a private key associated with it or not. The private key may be retrieved with DSA#private_key.

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 313


static VALUE
ossl_dsa_is_private(VALUE self)
{
    DSA *dsa;

    GetDSA(self, dsa);

    return DSA_PRIVATE(self, dsa) ? Qtrue : Qfalse;
}

#public? ⇒ `Boolean` (readonly)

Indicates whether this DSA instance has a public key associated with it or not. The public key may be retrieved with #public_key.

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 294


static VALUE
ossl_dsa_is_public(VALUE self)
{
    DSA *dsa;
    const BIGNUM *bn;

    GetDSA(self, dsa);
    DSA_get0_key(dsa, &bn, NULL);

    return bn ? Qtrue : Qfalse;
}

Instance Method Details

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`

Alias for #to_s.

#initialize_copy(other)

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 267


static VALUE
ossl_dsa_initialize_copy(VALUE self, VALUE other)
{
    EVP_PKEY *pkey;
    DSA *dsa, *dsa_new;

    GetPKey(self, pkey);
    if (EVP_PKEY_base_id(pkey) != EVP_PKEY_NONE)
	ossl_raise(eDSAError, "DSA already initialized");
    GetDSA(other, dsa);

    dsa_new = ASN1_dup((i2d_of_void *)i2d_DSAPrivateKey, (d2i_of_void *)d2i_DSAPrivateKey, (char *)dsa);
    if (!dsa_new)
	ossl_raise(eDSAError, "ASN1_dup");

    EVP_PKEY_assign_DSA(pkey, dsa_new);

    return self;
}

#params ⇒ `Hash`

Stores all parameters of key to the hash INSECURE: PRIVATE INFORMATIONS CAN LEAK OUT!!! Don’t use :-)) (I’s up to you)

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 415


static VALUE
ossl_dsa_get_params(VALUE self)
{
    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;
}

#public_key ⇒ `DSA`

Returns a new DSA instance that carries just the public key information. If the current instance has also private key information, this will no longer be present in the new instance. This feature is helpful for publishing the public key information without leaking any of the private information.

Example

dsa = OpenSSL::PKey::DSA.new(2048) # has public and private information
pub_key = dsa.public_key # has only the public part available
pub_key_der = pub_key.to_der # it's safe to publish this

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 481


static VALUE
ossl_dsa_to_public_key(VALUE self)
{
    EVP_PKEY *pkey;
    DSA *dsa;
    VALUE obj;

    GetPKeyDSA(self, pkey);
    /* err check performed by dsa_instance */
#define DSAPublicKey_dup(dsa) (DSA *)ASN1_dup( \
	(i2d_of_void *)i2d_DSAPublicKey, (d2i_of_void *)d2i_DSAPublicKey, (char *)(dsa))
    dsa = DSAPublicKey_dup(EVP_PKEY_get0_DSA(pkey));
#undef DSAPublicKey_dup
    obj = dsa_instance(rb_obj_class(self), dsa);
    if (obj == Qfalse) {
	DSA_free(dsa);
	ossl_raise(eDSAError, NULL);
    }
    return obj;
}

#set_key(pub_key, priv_key) ⇒ `self`

Sets pub_key and priv_key for the DSA instance. priv_key may be nil.

[ GitHub ]

#set_pqg(p, q, g) ⇒ `self`

Sets p, q, g to the DSA instance.

[ GitHub ]

#syssign(string) ⇒ `String`

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.

Parameters

string is a message digest of the original input data to be signed.

Example

dsa = OpenSSL::PKey::DSA.new(2048)
doc = "Sign me"
digest = OpenSSL::Digest::SHA1.digest(doc)
sig = dsa.syssign(digest)

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 521


static VALUE
ossl_dsa_sign(VALUE self, VALUE data)
{
    DSA *dsa;
    const BIGNUM *dsa_q;
    unsigned int buf_len;
    VALUE str;

    GetDSA(self, dsa);
    DSA_get0_pqg(dsa, NULL, &dsa_q, NULL);
    if (!dsa_q)
	ossl_raise(eDSAError, "incomplete DSA");
    if (!DSA_PRIVATE(self, dsa))
	ossl_raise(eDSAError, "Private DSA key needed!");
    StringValue(data);
    str = rb_str_new(0, DSA_size(dsa));
    if (!DSA_sign(0, (unsigned char *)RSTRING_PTR(data), RSTRING_LENINT(data),
		  (unsigned char *)RSTRING_PTR(str),
		  &buf_len, dsa)) { /* type is ignored (0) */
	ossl_raise(eDSAError, NULL);
    }
    rb_str_set_len(str, buf_len);

    return str;
}

#sysverify(digest, sig) ⇒ `Boolean`

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.

Parameters

digest is a message digest of the original input data to be signed
sig is a DSA signature value

Example

dsa = OpenSSL::PKey::DSA.new(2048)
doc = "Sign me"
digest = OpenSSL::Digest::SHA1.digest(doc)
sig = dsa.syssign(digest)
puts dsa.sysverify(digest, sig) # => true

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 566


static VALUE
ossl_dsa_verify(VALUE self, VALUE digest, VALUE sig)
{
    DSA *dsa;
    int ret;

    GetDSA(self, dsa);
    StringValue(digest);
    StringValue(sig);
    /* type is ignored (0) */
    ret = DSA_verify(0, (unsigned char *)RSTRING_PTR(digest), RSTRING_LENINT(digest),
		     (unsigned char *)RSTRING_PTR(sig), RSTRING_LENINT(sig), dsa);
    if (ret < 0) {
	ossl_raise(eDSAError, NULL);
    }
    else if (ret == 1) {
	return Qtrue;
    }

    return Qfalse;
}

#to_der ⇒ `String`

Encodes this DSA to its DER encoding.

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 381


static VALUE
ossl_dsa_to_der(VALUE self)
{
    DSA *dsa;
    int (*i2d_func)(DSA *, unsigned char **);
    unsigned char *p;
    long len;
    VALUE str;

    GetDSA(self, dsa);
    if(DSA_HAS_PRIVATE(dsa))
	i2d_func = (int (*)(DSA *,unsigned char **))i2d_DSAPrivateKey;
    else
	i2d_func = i2d_DSA_PUBKEY;
    if((len = i2d_func(dsa, NULL)) <= 0)
	ossl_raise(eDSAError, NULL);
    str = rb_str_new(0, len);
    p = (unsigned char *)RSTRING_PTR(str);
    if(i2d_func(dsa, &p) < 0)
	ossl_raise(eDSAError, NULL);
    ossl_str_adjust(str, p);

    return str;
}

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`

Alias for #to_s.

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`
Also known as: #export, #to_pem

Encodes this DSA to its PEM encoding.

Parameters

cipher is an ::OpenSSL::Cipher.
password is a string containing your password.

Examples

DSA.to_pem -> aString
DSA.to_pem(cipher, 'mypassword') -> aString

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 340


static VALUE
ossl_dsa_export(int argc, VALUE *argv, VALUE self)
{
    DSA *dsa;
    BIO *out;
    const EVP_CIPHER *ciph = NULL;
    VALUE cipher, pass, str;

    GetDSA(self, dsa);
    rb_scan_args(argc, argv, "02", &cipher, &pass);
    if (!NIL_P(cipher)) {
	ciph = ossl_evp_get_cipherbyname(cipher);
	pass = ossl_pem_passwd_value(pass);
    }
    if (!(out = BIO_new(BIO_s_mem()))) {
	ossl_raise(eDSAError, NULL);
    }
    if (DSA_HAS_PRIVATE(dsa)) {
	if (!PEM_write_bio_DSAPrivateKey(out, dsa, ciph, NULL, 0,
					 ossl_pem_passwd_cb, (void *)pass)){
	    BIO_free(out);
	    ossl_raise(eDSAError, NULL);
	}
    } else {
	if (!PEM_write_bio_DSA_PUBKEY(out, dsa)) {
	    BIO_free(out);
	    ossl_raise(eDSAError, NULL);
	}
    }
    str = ossl_membio2str(out);

    return str;
}

#to_text ⇒ `String`

Prints all parameters of key to buffer INSECURE: PRIVATE INFORMATIONS CAN LEAK OUT!!! Don’t use :-)) (I’s up to you)

[ GitHub ]

# File 'ext/openssl/ossl_pkey_dsa.c', line 444


static VALUE
ossl_dsa_to_text(VALUE self)
{
    DSA *dsa;
    BIO *out;
    VALUE str;

    GetDSA(self, dsa);
    if (!(out = BIO_new(BIO_s_mem()))) {
	ossl_raise(eDSAError, NULL);
    }
    if (!DSA_print(out, dsa, 0)) { /* offset = 0 */
	BIO_free(out);
	ossl_raise(eDSAError, NULL);
    }
    str = ossl_membio2str(out);

    return str;
}

Class: OpenSSL::PKey::DSA

Overview

Class Method Summary

PKey - Inherited

Instance Attribute Summary

Instance Method Summary

PKey - Inherited

Constructor Details

.new ⇒ DSA .new(size) ⇒ DSA .new(string [, pass]) ⇒ DSA

Parameters

Examples

Class Method Details

.generate(size) ⇒ DSA

Parameters

Instance Attribute Details

#private? ⇒ Boolean (readonly)

#public? ⇒ Boolean (readonly)

Instance Method Details

#export([cipher, password]) ⇒ String #to_pem([cipher, password]) ⇒ String #to_s([cipher, password]) ⇒ String

#initialize_copy(other)

#params ⇒ Hash

#public_key ⇒ DSA

Example

#set_key(pub_key, priv_key) ⇒ self

#set_pqg(p, q, g) ⇒ self

#syssign(string) ⇒ String

Parameters

Example

#sysverify(digest, sig) ⇒ Boolean

Parameters

Example

#to_der ⇒ String

#export([cipher, password]) ⇒ String #to_pem([cipher, password]) ⇒ String #to_s([cipher, password]) ⇒ String

#export([cipher, password]) ⇒ String #to_pem([cipher, password]) ⇒ String #to_s([cipher, password]) ⇒ String Also known as: #export, #to_pem

Parameters

Examples

#to_text ⇒ String

`PKey` - Inherited

`PKey` - Inherited

.new ⇒ `DSA` .new(size) ⇒ `DSA` .new(string [, pass]) ⇒ `DSA`

.generate(size) ⇒ `DSA`

#private? ⇒ `Boolean` (readonly)

#public? ⇒ `Boolean` (readonly)

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`

#params ⇒ `Hash`

#public_key ⇒ `DSA`

#set_key(pub_key, priv_key) ⇒ `self`

#set_pqg(p, q, g) ⇒ `self`

#syssign(string) ⇒ `String`

#sysverify(digest, sig) ⇒ `Boolean`

#to_der ⇒ `String`

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`

#export([cipher, password]) ⇒ `String` #to_pem([cipher, password]) ⇒ `String` #to_s([cipher, password]) ⇒ `String`
Also known as: #export, #to_pem

#to_text ⇒ `String`