class OpenSSL::PKey::RSA
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
- NO_PADDING
- PKCS1_OAEP_PADDING
- PKCS1_PADDING
- SSLV23_PADDING
Public Class Methods
Generates an RSA keypair.
See also OpenSSL::PKey.generate_key
.
size
-
The desired key size in bits.
exponent
-
An odd
Integer
, normally 3, 17, or 65537.
# File 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 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'
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; }
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 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 ofOpenSSL::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.
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); }
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; }
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)
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; }
Does this keypair contain a private key?
static VALUE ossl_rsa_is_private(VALUE self) { OSSL_3_const RSA *rsa; GetRSA(self, rsa); return RSA_PRIVATE(self, rsa) ? Qtrue : Qfalse; }
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.
# File 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
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.
# File 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
The return value is always true
since every private key is also a public key.
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; }
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.
# File 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
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.
# File 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
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
.
# File openssl/lib/openssl/pkey.rb, line 327 def public_key OpenSSL::PKey.read(public_to_der) end
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.
Sets p, q for the RSA
instance.
Sets n, e, d for the RSA
instance.
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
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); }
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.
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 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 ofOpenSSL::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.
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 ofOpenSSL::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.
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.
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); }
Private Instance Methods
# File 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