OpenSSL::PKey::RSA

Class

RSA is an asymmetric public key algorithm that has been formalized in RFC 3447. It is in widespread use in public key infrastructures (PKI) where certificates (cf. OpenSSL::X509::Certificate) often are issued on the basis of a public/private RSA key pair. RSA is used in a wide field of applications such as secure (symmetric) key exchange, e.g. when establishing a secure TLS/SSL connection. It is also used in various digital signature schemes.

Constants

PKCS1_PADDING

No documentation available

SSLV23_PADDING

No documentation available

NO_PADDING

No documentation available

PKCS1_OAEP_PADDING

No documentation available

Class Methods

RSA.generate(size, exponent = 65537) → RSA

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 343
def generate(size, exp = 0x10001, &blk)
  OpenSSL::PKey.generate_key("RSA", {
    "rsa_keygen_bits" => size,
    "rsa_keygen_pubexp" => exp,
  }, &blk)
end

Generates an RSA keypair.

RSA.new → rsa

RSA.new(encoded_key [, password ]) → rsa

RSA.new(encoded_key) { password } → rsa

RSA.new(size [, exponent]) → rsa

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_initialize(int argc, VALUE *argv, VALUE self)
{
    EVP_PKEY *pkey;
    RSA *rsa;
    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 RSA.new(size, generator) form is handled by lib/openssl/pkey.rb */
    rb_scan_args(argc, argv, "02", &arg, &pass);
    if (argc == 0) {
        rsa = RSA_new();
        if (!rsa)
            ossl_raise(eRSAError, "RSA_new");
        goto legacy;
    }

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

    /* First try RSAPublicKey format */
    rsa = d2i_RSAPublicKey_bio(in, NULL);
    if (rsa)
        goto legacy;
    OSSL_BIO_reset(in);
    rsa = PEM_read_bio_RSAPublicKey(in, NULL, NULL, NULL);
    if (rsa)
        goto legacy;
    OSSL_BIO_reset(in);

    /* Use the generic routine */
    pkey = ossl_pkey_read_generic(in, pass);
    BIO_free(in);
    if (!pkey)
        ossl_raise(eRSAError, "Neither PUB key nor PRIV key");

    type = EVP_PKEY_base_id(pkey);
    if (type != EVP_PKEY_RSA) {
        EVP_PKEY_free(pkey);
        rb_raise(eRSAError, "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_RSA(pkey, rsa) != 1) {
        EVP_PKEY_free(pkey);
        RSA_free(rsa);
        ossl_raise(eRSAError, "EVP_PKEY_assign_RSA");
    }
    RTYPEDDATA_DATA(self) = pkey;
    return self;
}

Generates or loads an RSA keypair.

If called without arguments, creates a new instance with no key components set. They can be set individually by set_key, set_factors, and set_crt_params.

If called with a String, tries to parse as DER or PEM encoding of an RSA key. Note that if password is not specified, but the key is encrypted with a password, OpenSSL will prompt for it. See also OpenSSL::PKey.read which can parse keys of any kind.

If called with a number, generates a new key pair. This form works as an alias of RSA.generate.

Examples:

OpenSSL::PKey::RSA.new 2048
OpenSSL::PKey::RSA.new File.read 'rsa.pem'
OpenSSL::PKey::RSA.new File.read('rsa.pem'), 'my password'

Instance Methods

rsa.export([cipher, password]) => PEM-format String

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_export(int argc, VALUE *argv, VALUE self)
{
    if (can_export_rsaprivatekey(self))
        return ossl_pkey_export_traditional(argc, argv, self, 0);
    else
        return ossl_pkey_export_spki(self, 0);
}

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 the key is a public key or a private key.

When the key contains private components, and no parameters are given

Serializes it into a PKCS #1 RSAPrivateKey.

A PEM-encoded key will look like:

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

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

Serializes it into a PKCS #1 RSAPrivateKey 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 RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,733F5302505B34701FC41F5C0746E4C0

[...]
-----END RSA 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 PKCS #1 RSAPrivateKey format is required.

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

initialize_copy(p1)

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            HAVE_EVP_PKEY_DUP
static VALUE
ossl_rsa_initialize_copy(VALUE self, VALUE other)
{
    EVP_PKEY *pkey;
    RSA *rsa, *rsa_new;

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

    rsa_new = (RSA *)ASN1_dup((i2d_of_void *)i2d_RSAPrivateKey,
                              (d2i_of_void *)d2i_RSAPrivateKey,
                              (char *)rsa);
    if (!rsa_new)
        ossl_raise(eRSAError, "ASN1_dup");

    pkey = EVP_PKEY_new();
    if (!pkey || EVP_PKEY_assign_RSA(pkey, rsa_new) != 1) {
        RSA_free(rsa_new);
        ossl_raise(eRSAError, "EVP_PKEY_assign_RSA");
    }
    RTYPEDDATA_DATA(self) = pkey;

    return self;
}

No documentation available

rsa.params => hash

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_get_params(VALUE self)
{
    OSSL_3_const RSA *rsa;
    VALUE hash;
    const BIGNUM *n, *e, *d, *p, *q, *dmp1, *dmq1, *iqmp;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &n, &e, &d);
    RSA_get0_factors(rsa, &p, &q);
    RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);

    hash = rb_hash_new();
    rb_hash_aset(hash, rb_str_new2("n"), ossl_bn_new(n));
    rb_hash_aset(hash, rb_str_new2("e"), ossl_bn_new(e));
    rb_hash_aset(hash, rb_str_new2("d"), ossl_bn_new(d));
    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("dmp1"), ossl_bn_new(dmp1));
    rb_hash_aset(hash, rb_str_new2("dmq1"), ossl_bn_new(dmq1));
    rb_hash_aset(hash, rb_str_new2("iqmp"), ossl_bn_new(iqmp));

    return hash;
}

THIS METHOD IS INSECURE, PRIVATE INFORMATION CAN LEAK OUT!!!

Stores all parameters of key to the hash. The hash has keys ‘n’, ‘e’, ‘d’, ‘p’, ‘q’, ‘dmp1’, ‘dmq1’, ‘iqmp’.

Don’t use :-)) (It’s up to you)

rsa.private? => true | false

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_is_private(VALUE self)
{
    OSSL_3_const RSA *rsa;

    GetRSA(self, rsa);

    return RSA_PRIVATE(self, rsa) ? Qtrue : Qfalse;
}

Does this keypair contain a private key?

rsa.private_decrypt(string) → String

rsa.private_decrypt(string, padding) → String

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 439
def private_decrypt(data, padding = PKCS1_PADDING)
  n or raise OpenSSL::PKey::RSAError, "incomplete RSA"
  private? or raise OpenSSL::PKey::RSAError, "private key needed."
  begin
    decrypt(data, {
      "rsa_padding_mode" => translate_padding_mode(padding),
    })
  rescue OpenSSL::PKey::PKeyError
    raise OpenSSL::PKey::RSAError, $!.message
  end
end

Decrypt string, which has been encrypted with the public key, with the private key. padding defaults to PKCS1_PADDING, which is known to be insecure but is kept for backwards compatibility.

Deprecated in version 3.0. Consider using PKey::PKey#encrypt and PKey::PKey#decrypt instead.

rsa.private_encrypt(string) → String

rsa.private_encrypt(string, padding) → String

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 373
def private_encrypt(string, padding = PKCS1_PADDING)
  n or raise OpenSSL::PKey::RSAError, "incomplete RSA"
  private? or raise OpenSSL::PKey::RSAError, "private key needed."
  begin
    sign_raw(nil, string, {
      "rsa_padding_mode" => translate_padding_mode(padding),
    })
  rescue OpenSSL::PKey::PKeyError
    raise OpenSSL::PKey::RSAError, $!.message
  end
end

Encrypt string with the private key. padding defaults to PKCS1_PADDING, which is known to be insecure but is kept for backwards compatibility. The encrypted string output can be decrypted using public_decrypt.

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

rsa.public? => true

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_is_public(VALUE self)
{
    OSSL_3_const RSA *rsa;

    GetRSA(self, rsa);
    /*
     * This method should check for n and e.  BUG.
     */
    (void)rsa;
    return Qtrue;
}

The return value is always true since every private key is also a public key.

rsa.public_decrypt(string) → String

rsa.public_decrypt(string, padding) → String

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 396
def public_decrypt(string, padding = PKCS1_PADDING)
  n or raise OpenSSL::PKey::RSAError, "incomplete RSA"
  begin
    verify_recover(nil, string, {
      "rsa_padding_mode" => translate_padding_mode(padding),
    })
  rescue OpenSSL::PKey::PKeyError
    raise OpenSSL::PKey::RSAError, $!.message
  end
end

Decrypt string, which has been encrypted with the private key, with the public key. padding defaults to PKCS1_PADDING which is known to be insecure but is kept for backwards compatibility.

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

rsa.public_encrypt(string) → String

rsa.public_encrypt(string, padding) → String

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 418
def public_encrypt(data, padding = PKCS1_PADDING)
  n or raise OpenSSL::PKey::RSAError, "incomplete RSA"
  begin
    encrypt(data, {
      "rsa_padding_mode" => translate_padding_mode(padding),
    })
  rescue OpenSSL::PKey::PKeyError
    raise OpenSSL::PKey::RSAError, $!.message
  end
end

Encrypt string with the public key. padding defaults to PKCS1_PADDING, which is known to be insecure but is kept for backwards compatibility. The encrypted string output can be decrypted using private_decrypt.

Deprecated in version 3.0. Consider using PKey::PKey#encrypt and PKey::PKey#decrypt instead.

rsa.public_key → rsanew

ext/openssl/lib/openssl/pkey.rb View on GitHub

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 327
def public_key
  OpenSSL::PKey.read(public_to_der)
end

Returns a new RSA instance that carries just the public key components.

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.

rsa.set_crt_params(dmp1, dmq1, iqmp) → self

ext/openssl/ossl_pkey_rsa.c View on GitHub

Sets dmp1, dmq1, iqmp for the RSA instance. They are calculated by d mod (p - 1), d mod (q - 1) and q^(-1) mod p respectively.

rsa.set_factors(p, q) → self

ext/openssl/ossl_pkey_rsa.c View on GitHub

Sets p, q for the RSA instance.

rsa.set_key(n, e, d) → self

ext/openssl/ossl_pkey_rsa.c View on GitHub

Sets n, e, d for the RSA instance.

rsa.sign_pss(digest, data, salt_length:, mgf1_hash:) → String

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_sign_pss(int argc, VALUE *argv, VALUE self)
{
    VALUE digest, data, options, kwargs[2], signature;
    static ID kwargs_ids[2];
    EVP_PKEY *pkey;
    EVP_PKEY_CTX *pkey_ctx;
    const EVP_MD *md, *mgf1md;
    EVP_MD_CTX *md_ctx;
    size_t buf_len;
    int salt_len;

    if (!kwargs_ids[0]) {
        kwargs_ids[0] = rb_intern_const("salt_length");
        kwargs_ids[1] = rb_intern_const("mgf1_hash");
    }
    rb_scan_args(argc, argv, "2:", &digest, &data, &options);
    rb_get_kwargs(options, kwargs_ids, 2, 0, kwargs);
    if (kwargs[0] == ID2SYM(rb_intern("max")))
        salt_len = -2; /* RSA_PSS_SALTLEN_MAX_SIGN */
    else if (kwargs[0] == ID2SYM(rb_intern("digest")))
        salt_len = -1; /* RSA_PSS_SALTLEN_DIGEST */
    else
        salt_len = NUM2INT(kwargs[0]);
    mgf1md = ossl_evp_get_digestbyname(kwargs[1]);

    pkey = GetPrivPKeyPtr(self);
    buf_len = EVP_PKEY_size(pkey);
    md = ossl_evp_get_digestbyname(digest);
    StringValue(data);
    signature = rb_str_new(NULL, (long)buf_len);

    md_ctx = EVP_MD_CTX_new();
    if (!md_ctx)
        goto err;

    if (EVP_DigestSignInit(md_ctx, &pkey_ctx, md, NULL, pkey) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, salt_len) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkey_ctx, mgf1md) != 1)
        goto err;

    if (EVP_DigestSignUpdate(md_ctx, RSTRING_PTR(data), RSTRING_LEN(data)) != 1)
        goto err;

    if (EVP_DigestSignFinal(md_ctx, (unsigned char *)RSTRING_PTR(signature), &buf_len) != 1)
        goto err;

    rb_str_set_len(signature, (long)buf_len);

    EVP_MD_CTX_free(md_ctx);
    return signature;

  err:
    EVP_MD_CTX_free(md_ctx);
    ossl_raise(eRSAError, NULL);
}

Signs data using the Probabilistic Signature Scheme (RSA-PSS) and returns the calculated signature.

RSAError will be raised if an error occurs.

See verify_pss for the verification operation.

Parameters

digest: A String containing the message digest algorithm name.
data: A String. The data to be signed.
salt_length: The length in octets of the salt. Two special values are reserved: :digest means the digest length, and :max means the maximum possible length for the combination of the private key and the selected message digest algorithm.
mgf1_hash: The hash algorithm used in MGF1 (the currently supported mask generation function (MGF)).

Example

data = "Sign me!"
pkey = OpenSSL::PKey::RSA.new(2048)
signature = pkey.sign_pss("SHA256", data, salt_length: :max, mgf1_hash: "SHA256")
pub_key = OpenSSL::PKey.read(pkey.public_to_der)
puts pub_key.verify_pss("SHA256", signature, data,
                        salt_length: :auto, mgf1_hash: "SHA256") # => true

rsa.to_der => DER-format String

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_to_der(VALUE self)
{
    if (can_export_rsaprivatekey(self))
        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 DER-encoding.

See to_pem for details.

This method is kept for compatibility. This should only be used when the PKCS #1 RSAPrivateKey format is required.

Consider using public_to_der or private_to_der instead.

          
            # File tmp/rubies/ruby-3.3.0/ext/openssl/lib/openssl/pkey.rb, line 456
        def translate_padding_mode(num)
  case num
  when PKCS1_PADDING
    "pkcs1"
  when SSLV23_PADDING
    "sslv23"
  when NO_PADDING
    "none"
  when PKCS1_OAEP_PADDING
    "oaep"
  else
    raise OpenSSL::PKey::PKeyError, "unsupported padding mode"
  end
end

No documentation available

rsa.verify_pss(digest, signature, data, salt_length:, mgf1_hash:) → true | false

ext/openssl/ossl_pkey_rsa.c View on GitHub

          
            static VALUE
ossl_rsa_verify_pss(int argc, VALUE *argv, VALUE self)
{
    VALUE digest, signature, data, options, kwargs[2];
    static ID kwargs_ids[2];
    EVP_PKEY *pkey;
    EVP_PKEY_CTX *pkey_ctx;
    const EVP_MD *md, *mgf1md;
    EVP_MD_CTX *md_ctx;
    int result, salt_len;

    if (!kwargs_ids[0]) {
        kwargs_ids[0] = rb_intern_const("salt_length");
        kwargs_ids[1] = rb_intern_const("mgf1_hash");
    }
    rb_scan_args(argc, argv, "3:", &digest, &signature, &data, &options);
    rb_get_kwargs(options, kwargs_ids, 2, 0, kwargs);
    if (kwargs[0] == ID2SYM(rb_intern("auto")))
        salt_len = -2; /* RSA_PSS_SALTLEN_AUTO */
    else if (kwargs[0] == ID2SYM(rb_intern("digest")))
        salt_len = -1; /* RSA_PSS_SALTLEN_DIGEST */
    else
        salt_len = NUM2INT(kwargs[0]);
    mgf1md = ossl_evp_get_digestbyname(kwargs[1]);

    GetPKey(self, pkey);
    md = ossl_evp_get_digestbyname(digest);
    StringValue(signature);
    StringValue(data);

    md_ctx = EVP_MD_CTX_new();
    if (!md_ctx)
        goto err;

    if (EVP_DigestVerifyInit(md_ctx, &pkey_ctx, md, NULL, pkey) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_padding(pkey_ctx, RSA_PKCS1_PSS_PADDING) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_pss_saltlen(pkey_ctx, salt_len) != 1)
        goto err;

    if (EVP_PKEY_CTX_set_rsa_mgf1_md(pkey_ctx, mgf1md) != 1)
        goto err;

    if (EVP_DigestVerifyUpdate(md_ctx, RSTRING_PTR(data), RSTRING_LEN(data)) != 1)
        goto err;

    result = EVP_DigestVerifyFinal(md_ctx,
                                   (unsigned char *)RSTRING_PTR(signature),
                                   RSTRING_LEN(signature));

    switch (result) {
      case 0:
        ossl_clear_error();
        EVP_MD_CTX_free(md_ctx);
        return Qfalse;
      case 1:
        EVP_MD_CTX_free(md_ctx);
        return Qtrue;
      default:
        goto err;
    }

  err:
    EVP_MD_CTX_free(md_ctx);
    ossl_raise(eRSAError, NULL);
}

Verifies data using the Probabilistic Signature Scheme (RSA-PSS).

The return value is true if the signature is valid, false otherwise. RSAError will be raised if an error occurs.

See sign_pss for the signing operation and an example code.

Parameters

digest: A String containing the message digest algorithm name.
data: A String. The data to be signed.
salt_length: The length in octets of the salt. Two special values are reserved: :digest means the digest length, and :auto means automatically determining the length based on the signature.
mgf1_hash: The hash algorithm used in MGF1.

OpenSSL::PKey::RSA

PKCS1_PADDING

SSLV23_PADDING

NO_PADDING

PKCS1_OAEP_PADDING

RSA.generate(size, exponent = 65537) → RSA

RSA.new → rsa

RSA.new(encoded_key [, password ]) → rsa

RSA.new(encoded_key) { password } → rsa

RSA.new(size [, exponent]) → rsa

rsa.export([cipher, password]) => PEM-format String

initialize_copy(p1)

rsa.params => hash

rsa.private? => true | false

rsa.private_decrypt(string) → String

rsa.private_decrypt(string, padding) → String

rsa.private_encrypt(string) → String

rsa.private_encrypt(string, padding) → String

rsa.public? => true

rsa.public_decrypt(string) → String

rsa.public_decrypt(string, padding) → String

rsa.public_encrypt(string) → String

rsa.public_encrypt(string, padding) → String

rsa.public_key → rsanew

rsa.set_crt_params(dmp1, dmq1, iqmp) → self

rsa.set_factors(p, q) → self

rsa.set_key(n, e, d) → self

rsa.sign_pss(digest, data, salt_length:, mgf1_hash:) → String

Parameters

Example

rsa.to_der => DER-format String

rsa.to_pem([cipher, password]) => PEM-format String

rsa.to_s([cipher, password]) => PEM-format String

translate_padding_mode(num)

rsa.verify_pss(digest, signature, data, salt_length:, mgf1_hash:) → true | false

Parameters