class OpenSSL::PKey::EC

OpenSSL::PKey::EC provides access to Elliptic Curve Digital Signature Algorithm (ECDSA) and Elliptic Curve Diffie-Hellman (ECDH).

Key exchange¶ ↑

ec1 = OpenSSL::PKey::EC.generate("prime256v1")
ec2 = OpenSSL::PKey::EC.generate("prime256v1")
# ec1 and ec2 have own private key respectively
shared_key1 = ec1.dh_compute_key(ec2.public_key)
shared_key2 = ec2.dh_compute_key(ec1.public_key)

p shared_key1 == shared_key2 #=> true

Constants

EXPLICIT_CURVE
NAMED_CURVE

Public Class Methods

builtin_curves → [[sn, comment], ...]

Obtains a list of all predefined curves by the OpenSSL. Curve names are returned as sn.

See the OpenSSL documentation for EC_get_builtin_curves().

static VALUE ossl_s_builtin_curves(VALUE self)
{
    EC_builtin_curve *curves = NULL;
    int n;
    int crv_len = rb_long2int(EC_get_builtin_curves(NULL, 0));
    VALUE ary, ret;

    curves = ALLOCA_N(EC_builtin_curve, crv_len);
    if (curves == NULL)
        return Qnil;
    if (!EC_get_builtin_curves(curves, crv_len))
        ossl_raise(rb_eRuntimeError, "EC_get_builtin_curves");

    ret = rb_ary_new2(crv_len);

    for (n = 0; n < crv_len; n++) {
        const char *sname = OBJ_nid2sn(curves[n].nid);
        const char *comment = curves[n].comment;

        ary = rb_ary_new2(2);
        rb_ary_push(ary, rb_str_new2(sname));
        rb_ary_push(ary, comment ? rb_str_new2(comment) : Qnil);
        rb_ary_push(ret, ary);
    }

    return ret;
}

generate(ec_group) → ec

generate(string) → ec

Creates a new EC instance with a new random private and public key.

static VALUE
ossl_ec_key_s_generate(VALUE klass, VALUE arg)
{
    EVP_PKEY *pkey;
    EC_KEY *ec;
    VALUE obj;

    obj = rb_obj_alloc(klass);

    ec = ec_key_new_from_group(arg);
    pkey = EVP_PKEY_new();
    if (!pkey || EVP_PKEY_assign_EC_KEY(pkey, ec) != 1) {
        EVP_PKEY_free(pkey);
        EC_KEY_free(ec);
        ossl_raise(eECError, "EVP_PKEY_assign_EC_KEY");
    }
    RTYPEDDATA_DATA(obj) = pkey;

    if (!EC_KEY_generate_key(ec))
        ossl_raise(eECError, "EC_KEY_generate_key");

    return obj;
}

OpenSSL::PKey::EC.new

OpenSSL::PKey::EC.new(ec_key)

OpenSSL::PKey::EC.new(ec_group)

OpenSSL::PKey::EC.new("secp112r1")

OpenSSL::PKey::EC.new(pem_string [, pwd])

OpenSSL::PKey::EC.new(der_string)

Creates a new EC object from given arguments.

static VALUE ossl_ec_key_initialize(int argc, VALUE *argv, VALUE self)
{
    EVP_PKEY *pkey;
    EC_KEY *ec;
    BIO *in;
    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");

    rb_scan_args(argc, argv, "02", &arg, &pass);
    if (NIL_P(arg)) {
        if (!(ec = EC_KEY_new()))
            ossl_raise(eECError, "EC_KEY_new");
        goto legacy;
    }
    else if (rb_obj_is_kind_of(arg, cEC_GROUP)) {
        ec = ec_key_new_from_group(arg);
        goto legacy;
    }

    pass = ossl_pem_passwd_value(pass);
    arg = ossl_to_der_if_possible(arg);
    in = ossl_obj2bio(&arg);

    pkey = ossl_pkey_read_generic(in, pass);
    BIO_free(in);
    if (!pkey) {
        ossl_clear_error();
        ec = ec_key_new_from_group(arg);
        goto legacy;
    }

    type = EVP_PKEY_base_id(pkey);
    if (type != EVP_PKEY_EC) {
        EVP_PKEY_free(pkey);
        rb_raise(eDSAError, "incorrect pkey type: %s", OBJ_nid2sn(type));
    }
    RTYPEDDATA_DATA(self) = pkey;
    return self;

  legacy:
    pkey = EVP_PKEY_new();
    if (!pkey || EVP_PKEY_assign_EC_KEY(pkey, ec) != 1) {
        EVP_PKEY_free(pkey);
        EC_KEY_free(ec);
        ossl_raise(eECError, "EVP_PKEY_assign_EC_KEY");
    }
    RTYPEDDATA_DATA(self) = pkey;
    return self;
}

Public Instance Methods

check_key → true

Raises an exception if the key is invalid.

See also the man page EVP_PKEY_public_check(3).

static VALUE ossl_ec_key_check_key(VALUE self)
{
#ifdef HAVE_EVP_PKEY_CHECK
    EVP_PKEY *pkey;
    EVP_PKEY_CTX *pctx;
    const EC_KEY *ec;

    GetPKey(self, pkey);
    GetEC(self, ec);
    pctx = EVP_PKEY_CTX_new(pkey, /* engine */NULL);
    if (!pctx)
        ossl_raise(eECError, "EVP_PKEY_CTX_new");

    if (EC_KEY_get0_private_key(ec) != NULL) {
        if (EVP_PKEY_check(pctx) != 1) {
            EVP_PKEY_CTX_free(pctx);
            ossl_raise(eECError, "EVP_PKEY_check");
        }
    }
    else {
        if (EVP_PKEY_public_check(pctx) != 1) {
            EVP_PKEY_CTX_free(pctx);
            ossl_raise(eECError, "EVP_PKEY_public_check");
        }
    }

    EVP_PKEY_CTX_free(pctx);
#else
    EC_KEY *ec;

    GetEC(self, ec);
    if (EC_KEY_check_key(ec) != 1)
        ossl_raise(eECError, "EC_KEY_check_key");
#endif

    return Qtrue;
}

dh_compute_key(pubkey) → string

Derives a shared secret by ECDH. pubkey must be an instance of OpenSSL::PKey::EC::Point and must belong to the same group.

This method is provided for backwards compatibility, and calls derive internally.

# File ext/openssl/lib/openssl/pkey.rb, line 284
def dh_compute_key(pubkey)
  obj = OpenSSL::ASN1.Sequence([
    OpenSSL::ASN1.Sequence([
      OpenSSL::ASN1.ObjectId("id-ecPublicKey"),
      group.to_der,
    ]),
    OpenSSL::ASN1.BitString(pubkey.to_octet_string(:uncompressed)),
  ])
  derive(OpenSSL::PKey.read(obj.to_der))
end

dsa_sign_asn1(data) → String

Deprecated in version 3.0. Consider using PKey::PKey#sign_raw and PKey::PKey#verify_raw instead.

# File ext/openssl/lib/openssl/pkey.rb, line 259
def dsa_sign_asn1(data)
  sign_raw(nil, data)
rescue OpenSSL::PKey::PKeyError
  raise OpenSSL::PKey::ECError, $!.message
end

dsa_verify_asn1(data, sig) → true | false

Deprecated in version 3.0. Consider using PKey::PKey#sign_raw and PKey::PKey#verify_raw instead.

# File ext/openssl/lib/openssl/pkey.rb, line 270
def dsa_verify_asn1(data, sig)
  verify_raw(nil, sig, data)
rescue OpenSSL::PKey::PKeyError
  raise OpenSSL::PKey::ECError, $!.message
end

export([cipher, password]) → String

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 SEC 1/RFC 5915 ECPrivateKey.

A PEM-encoded key will look like:

-----BEGIN EC PRIVATE KEY-----
[...]
-----END EC PRIVATE KEY-----

When the key contains private components, and cipher and password are given

Serializes it into a SEC 1/RFC 5915 ECPrivateKey and encrypts it in OpenSSL’s traditional PEM encryption format. cipher must be a cipher name understood by OpenSSL::Cipher.new or an instance of OpenSSL::Cipher.

An encrypted PEM-encoded key will look like:

-----BEGIN EC PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0

[...]
-----END EC 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 SEC 1/RFC 5915 ECPrivateKey format is required.

Consider using public_to_pem (X.509 SubjectPublicKeyInfo) or private_to_pem (PKCS #8 PrivateKeyInfo or EncryptedPrivateKeyInfo) instead.

static VALUE
ossl_ec_key_export(int argc, VALUE *argv, VALUE self)
{
    OSSL_3_const EC_KEY *ec;

    GetEC(self, ec);
    if (EC_KEY_get0_public_key(ec) == NULL)
        ossl_raise(eECError, "can't export - no public key set");
    if (EC_KEY_get0_private_key(ec))
        return ossl_pkey_export_traditional(argc, argv, self, 0);
    else
        return ossl_pkey_export_spki(self, 0);
}

Also aliased as: to_pem

generate_key

Alias for: generate_key!

generate_key! → self

Generates a new random private and public key.

See also the OpenSSL documentation for EC_KEY_generate_key()

Example¶ ↑

ec = OpenSSL::PKey::EC.new("prime256v1")
p ec.private_key # => nil
ec.generate_key!
p ec.private_key # => #<OpenSSL::BN XXXXXX>

static VALUE ossl_ec_key_generate_key(VALUE self)
{
#if OSSL_OPENSSL_PREREQ(3, 0, 0)
    rb_raise(ePKeyError, "pkeys are immutable on OpenSSL 3.0");
#else
    EC_KEY *ec;

    GetEC(self, ec);
    if (EC_KEY_generate_key(ec) != 1)
        ossl_raise(eECError, "EC_KEY_generate_key");

    return self;
#endif
}

Also aliased as: generate_key

group → group

Returns the EC::Group that the key is associated with. Modifying the returned group does not affect key.

static VALUE
ossl_ec_key_get_group(VALUE self)
{
    OSSL_3_const EC_KEY *ec;
    const EC_GROUP *group;

    GetEC(self, ec);
    group = EC_KEY_get0_group(ec);
    if (!group)
        return Qnil;

    return ec_group_new(group);
}

group = group

Sets the EC::Group for the key. The group structure is internally copied so modification to group after assigning to a key has no effect on the key.

static VALUE
ossl_ec_key_set_group(VALUE self, VALUE group_v)
{
#if OSSL_OPENSSL_PREREQ(3, 0, 0)
    rb_raise(ePKeyError, "pkeys are immutable on OpenSSL 3.0");
#else
    EC_KEY *ec;
    EC_GROUP *group;

    GetEC(self, ec);
    GetECGroup(group_v, group);

    if (EC_KEY_set_group(ec, group) != 1)
        ossl_raise(eECError, "EC_KEY_set_group");

    return group_v;
#endif
}

initialize_copy (p1)

HAVE_EVP_PKEY_DUP
static VALUE
ossl_ec_key_initialize_copy(VALUE self, VALUE other)
{
    EVP_PKEY *pkey;
    EC_KEY *ec, *ec_new;

    TypedData_Get_Struct(self, EVP_PKEY, &ossl_evp_pkey_type, pkey);
    if (pkey)
        rb_raise(rb_eTypeError, "pkey already initialized");
    GetEC(other, ec);

    ec_new = EC_KEY_dup(ec);
    if (!ec_new)
        ossl_raise(eECError, "EC_KEY_dup");

    pkey = EVP_PKEY_new();
    if (!pkey || EVP_PKEY_assign_EC_KEY(pkey, ec_new) != 1) {
        EC_KEY_free(ec_new);
        ossl_raise(eECError, "EVP_PKEY_assign_EC_KEY");
    }
    RTYPEDDATA_DATA(self) = pkey;

    return self;
}

private? → true or false

Returns whether this EC instance has a private key. The private key (BN) can be retrieved with EC#private_key.

static VALUE ossl_ec_key_is_private(VALUE self)
{
    OSSL_3_const EC_KEY *ec;

    GetEC(self, ec);

    return EC_KEY_get0_private_key(ec) ? Qtrue : Qfalse;
}

Also aliased as: private_key?

private_key → OpenSSL::BN

See the OpenSSL documentation for EC_KEY_get0_private_key()

static VALUE ossl_ec_key_get_private_key(VALUE self)
{
    OSSL_3_const EC_KEY *ec;
    const BIGNUM *bn;

    GetEC(self, ec);
    if ((bn = EC_KEY_get0_private_key(ec)) == NULL)
        return Qnil;

    return ossl_bn_new(bn);
}

private_key = openssl_bn

See the OpenSSL documentation for EC_KEY_set_private_key()

static VALUE ossl_ec_key_set_private_key(VALUE self, VALUE private_key)
{
#if OSSL_OPENSSL_PREREQ(3, 0, 0)
    rb_raise(ePKeyError, "pkeys are immutable on OpenSSL 3.0");
#else
    EC_KEY *ec;
    BIGNUM *bn = NULL;

    GetEC(self, ec);
    if (!NIL_P(private_key))
        bn = GetBNPtr(private_key);

    switch (EC_KEY_set_private_key(ec, bn)) {
    case 1:
        break;
    case 0:
        if (bn == NULL)
            break;
        /* fallthrough */
    default:
        ossl_raise(eECError, "EC_KEY_set_private_key");
    }

    return private_key;
#endif
}

private_key?

Alias for: private?

public? → true or false

Returns whether this EC instance has a public key. The public key (EC::Point) can be retrieved with EC#public_key.

static VALUE ossl_ec_key_is_public(VALUE self)
{
    OSSL_3_const EC_KEY *ec;

    GetEC(self, ec);

    return EC_KEY_get0_public_key(ec) ? Qtrue : Qfalse;
}

Also aliased as: public_key?

public_key → OpenSSL::PKey::EC::Point

See the OpenSSL documentation for EC_KEY_get0_public_key()

static VALUE ossl_ec_key_get_public_key(VALUE self)
{
    OSSL_3_const EC_KEY *ec;
    const EC_POINT *point;

    GetEC(self, ec);
    if ((point = EC_KEY_get0_public_key(ec)) == NULL)
        return Qnil;

    return ec_point_new(point, EC_KEY_get0_group(ec));
}

public_key = ec_point

See the OpenSSL documentation for EC_KEY_set_public_key()

static VALUE ossl_ec_key_set_public_key(VALUE self, VALUE public_key)
{
#if OSSL_OPENSSL_PREREQ(3, 0, 0)
    rb_raise(ePKeyError, "pkeys are immutable on OpenSSL 3.0");
#else
    EC_KEY *ec;
    EC_POINT *point = NULL;

    GetEC(self, ec);
    if (!NIL_P(public_key))
        GetECPoint(public_key, point);

    switch (EC_KEY_set_public_key(ec, point)) {
    case 1:
        break;
    case 0:
        if (point == NULL)
            break;
        /* fallthrough */
    default:
        ossl_raise(eECError, "EC_KEY_set_public_key");
    }

    return public_key;
#endif
}

public_key?

Alias for: public?

to_der → String

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 SEC 1/RFC 5915 ECPrivateKey format is required.

Consider using public_to_der or private_to_der instead.

static VALUE
ossl_ec_key_to_der(VALUE self)
{
    OSSL_3_const EC_KEY *ec;

    GetEC(self, ec);
    if (EC_KEY_get0_public_key(ec) == NULL)
        ossl_raise(eECError, "can't export - no public key set");
    if (EC_KEY_get0_private_key(ec))
        return ossl_pkey_export_traditional(0, NULL, self, 1);
    else
        return ossl_pkey_export_spki(self, 1);
}

to_pem([cipher, password]) → String

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 SEC 1/RFC 5915 ECPrivateKey.

A PEM-encoded key will look like:

-----BEGIN EC PRIVATE KEY-----
[...]
-----END EC PRIVATE KEY-----

When the key contains private components, and cipher and password are given

An encrypted PEM-encoded key will look like:

-----BEGIN EC PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0

[...]
-----END EC 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 SEC 1/RFC 5915 ECPrivateKey format is required.

Consider using public_to_pem (X.509 SubjectPublicKeyInfo) or private_to_pem (PKCS #8 PrivateKeyInfo or EncryptedPrivateKeyInfo) instead.

Alias for: export