Class: OpenSSL::PKey::RSA

Inherits:
PKey
  • Object
show all
Includes:
Marshal
Defined in:
ext/openssl/ossl_pkey_rsa.c,
lib/openssl/pkey.rb,
ext/openssl/ossl_pkey_rsa.c

Overview

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.

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Marshal

#_dump, included

Methods inherited from PKey

#inspect, #oid, #private_to_der, #private_to_pem, #public_to_der, #public_to_pem, #sign, #verify

Constructor Details

#new(key_size) ⇒ Object #new(encoded_key) ⇒ Object #new(encoded_key, pass_phrase) ⇒ Object

Generates or loads an RSA keypair. If an integer key_size is given it represents the desired key size. Keys less than 1024 bits should be considered insecure.

A key can instead be loaded from an encoded_key which must be PEM or DER encoded. A pass_phrase can be used to decrypt the key. If none is given OpenSSL will prompt for the pass phrase.

Examples

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



220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 220

static VALUE
ossl_rsa_initialize(int argc, VALUE *argv, VALUE self)
{
    EVP_PKEY *pkey;
    RSA *rsa;
    BIO *in;
    VALUE arg, pass;

    GetPKey(self, pkey);
    if(rb_scan_args(argc, argv, "02", &arg, &pass) == 0) {
	rsa = RSA_new();
    }
    else if (RB_INTEGER_TYPE_P(arg)) {
	rsa = rsa_generate(NUM2INT(arg), NIL_P(pass) ? RSA_F4 : NUM2ULONG(pass));
	if (!rsa) ossl_raise(eRSAError, NULL);
    }
    else {
	pass = ossl_pem_passwd_value(pass);
	arg = ossl_to_der_if_possible(arg);
	in = ossl_obj2bio(&arg);
	rsa = PEM_read_bio_RSAPrivateKey(in, NULL, ossl_pem_passwd_cb, (void *)pass);
	if (!rsa) {
	    OSSL_BIO_reset(in);
	    rsa = PEM_read_bio_RSA_PUBKEY(in, NULL, NULL, NULL);
	}
	if (!rsa) {
	    OSSL_BIO_reset(in);
	    rsa = d2i_RSAPrivateKey_bio(in, NULL);
	}
	if (!rsa) {
	    OSSL_BIO_reset(in);
	    rsa = d2i_RSA_PUBKEY_bio(in, NULL);
	}
	if (!rsa) {
	    OSSL_BIO_reset(in);
	    rsa = PEM_read_bio_RSAPublicKey(in, NULL, NULL, NULL);
	}
	if (!rsa) {
	    OSSL_BIO_reset(in);
	    rsa = d2i_RSAPublicKey_bio(in, NULL);
	}
	BIO_free(in);
	if (!rsa) {
	    ossl_raise(eRSAError, "Neither PUB key nor PRIV key");
	}
    }
    if (!EVP_PKEY_assign_RSA(pkey, rsa)) {
	RSA_free(rsa);
	ossl_raise(eRSAError, NULL);
    }

    return self;
}

Class Method Details

.generate(size) ⇒ Object .generate(size, exponent) ⇒ Object

Generates an RSA keypair. size is an integer representing the desired key size. Keys smaller than 1024 should be considered insecure. exponent is an odd number normally 3, 17, or 65537.



179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 179

static VALUE
ossl_rsa_s_generate(int argc, VALUE *argv, VALUE klass)
{
/* why does this method exist?  why can't initialize take an optional exponent? */
    RSA *rsa;
    VALUE size, exp;
    VALUE obj;

    rb_scan_args(argc, argv, "11", &size, &exp);

    rsa = rsa_generate(NUM2INT(size), NIL_P(exp) ? RSA_F4 : NUM2ULONG(exp)); /* err handled by rsa_instance */
    obj = rsa_instance(klass, rsa);

    if (obj == Qfalse) {
	RSA_free(rsa);
	ossl_raise(eRSAError, NULL);
    }

    return obj;
}

Instance Method Details

#export([cipher, pass_phrase]) ⇒ PEM-format String #to_pem([cipher, pass_phrase]) ⇒ PEM-format String #to_s([cipher, pass_phrase]) ⇒ PEM-format String Also known as: to_pem, to_s

Outputs this keypair in PEM encoding. If cipher and pass_phrase are given they will be used to encrypt the key. cipher must be an OpenSSL::Cipher instance.

Overloads:

  • #export([cipher, pass_phrase]) ⇒ PEM-format String

    Returns:

    • (PEM-format String)
  • #to_pem([cipher, pass_phrase]) ⇒ PEM-format String

    Returns:

    • (PEM-format String)
  • #to_s([cipher, pass_phrase]) ⇒ PEM-format String

    Returns:

    • (PEM-format String) 


340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 340

static VALUE
ossl_rsa_export(int argc, VALUE *argv, VALUE self)
{
    RSA *rsa;
    const BIGNUM *n, *e, *d, *p, *q, *dmp1, *dmq1, *iqmp;
    BIO *out;
    const EVP_CIPHER *ciph = NULL;
    VALUE cipher, pass, str;

    GetRSA(self, rsa);

    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(eRSAError, NULL);
    }
    RSA_get0_key(rsa, &n, &e, &d);
    RSA_get0_factors(rsa, &p, &q);
    RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
    if (n && e && d && p && q && dmp1 && dmq1 && iqmp) {
	if (!PEM_write_bio_RSAPrivateKey(out, rsa, ciph, NULL, 0,
					 ossl_pem_passwd_cb, (void *)pass)) {
	    BIO_free(out);
	    ossl_raise(eRSAError, NULL);
	}
    } else {
	if (!PEM_write_bio_RSA_PUBKEY(out, rsa)) {
	    BIO_free(out);
	    ossl_raise(eRSAError, NULL);
	}
    }
    str = ossl_membio2str(out);

    return str;
}

#initialize_copy(other) ⇒ Object 



274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 274

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

    GetPKey(self, pkey);
    if (EVP_PKEY_base_id(pkey) != EVP_PKEY_NONE)
	ossl_raise(eRSAError, "RSA already initialized");
    GetRSA(other, rsa);

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

    EVP_PKEY_assign_RSA(pkey, rsa_new);

    return self;
}

#params ⇒ 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)

Returns:

  • (Hash) 


748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 748

static VALUE
ossl_rsa_get_params(VALUE self)
{
    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;
}

#private? ⇒ Boolean

Does this keypair contain a private key?

Returns:

  • (Boolean) 


320
321
322
323
324
325
326
327
328
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 320

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

    GetRSA(self, rsa);

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

#private_decrypt(string) ⇒ String #private_decrypt(string, padding) ⇒ String

Decrypt string, which has been encrypted with the public key, with the private key. padding defaults to PKCS1_PADDING.

Overloads:

  • #private_decrypt(string) ⇒ String

    Returns:

    • (String)
  • #private_decrypt(string, padding) ⇒ String

    Returns:

    • (String) 


521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 521

static VALUE
ossl_rsa_private_decrypt(int argc, VALUE *argv, VALUE self)
{
    RSA *rsa;
    const BIGNUM *rsa_n;
    int buf_len, pad;
    VALUE str, buffer, padding;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &rsa_n, NULL, NULL);
    if (!rsa_n)
	ossl_raise(eRSAError, "incomplete RSA");
    if (!RSA_PRIVATE(self, rsa))
	ossl_raise(eRSAError, "private key needed.");
    rb_scan_args(argc, argv, "11", &buffer, &padding);
    pad = (argc == 1) ? RSA_PKCS1_PADDING : NUM2INT(padding);
    StringValue(buffer);
    str = rb_str_new(0, RSA_size(rsa));
    buf_len = RSA_private_decrypt(RSTRING_LENINT(buffer), (unsigned char *)RSTRING_PTR(buffer),
				  (unsigned char *)RSTRING_PTR(str), rsa, pad);
    if (buf_len < 0) ossl_raise(eRSAError, NULL);
    rb_str_set_len(str, buf_len);

    return str;
}

#private_encrypt(string) ⇒ String #private_encrypt(string, padding) ⇒ String

Encrypt string with the private key. padding defaults to PKCS1_PADDING. The encrypted string output can be decrypted using #public_decrypt.

Overloads:

  • #private_encrypt(string) ⇒ String

    Returns:

    • (String)
  • #private_encrypt(string, padding) ⇒ String

    Returns:

    • (String) 


487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 487

static VALUE
ossl_rsa_private_encrypt(int argc, VALUE *argv, VALUE self)
{
    RSA *rsa;
    const BIGNUM *rsa_n;
    int buf_len, pad;
    VALUE str, buffer, padding;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &rsa_n, NULL, NULL);
    if (!rsa_n)
	ossl_raise(eRSAError, "incomplete RSA");
    if (!RSA_PRIVATE(self, rsa))
	ossl_raise(eRSAError, "private key needed.");
    rb_scan_args(argc, argv, "11", &buffer, &padding);
    pad = (argc == 1) ? RSA_PKCS1_PADDING : NUM2INT(padding);
    StringValue(buffer);
    str = rb_str_new(0, RSA_size(rsa));
    buf_len = RSA_private_encrypt(RSTRING_LENINT(buffer), (unsigned char *)RSTRING_PTR(buffer),
				  (unsigned char *)RSTRING_PTR(str), rsa, pad);
    if (buf_len < 0) ossl_raise(eRSAError, NULL);
    rb_str_set_len(str, buf_len);

    return str;
}

#public? ⇒ true

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

Returns:

  • (true) 


301
302
303
304
305
306
307
308
309
310
311
312
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 301

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

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

#public_decrypt(string) ⇒ String #public_decrypt(string, padding) ⇒ String

Decrypt string, which has been encrypted with the private key, with the public key. padding defaults to PKCS1_PADDING.

Overloads:

  • #public_decrypt(string) ⇒ String

    Returns:

    • (String)
  • #public_decrypt(string, padding) ⇒ String

    Returns:

    • (String) 


455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 455

static VALUE
ossl_rsa_public_decrypt(int argc, VALUE *argv, VALUE self)
{
    RSA *rsa;
    const BIGNUM *rsa_n;
    int buf_len, pad;
    VALUE str, buffer, padding;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &rsa_n, NULL, NULL);
    if (!rsa_n)
	ossl_raise(eRSAError, "incomplete RSA");
    rb_scan_args(argc, argv, "11", &buffer, &padding);
    pad = (argc == 1) ? RSA_PKCS1_PADDING : NUM2INT(padding);
    StringValue(buffer);
    str = rb_str_new(0, RSA_size(rsa));
    buf_len = RSA_public_decrypt(RSTRING_LENINT(buffer), (unsigned char *)RSTRING_PTR(buffer),
				 (unsigned char *)RSTRING_PTR(str), rsa, pad);
    if (buf_len < 0) ossl_raise(eRSAError, NULL);
    rb_str_set_len(str, buf_len);

    return str;
}

#public_encrypt(string) ⇒ String #public_encrypt(string, padding) ⇒ String

Encrypt string with the public key. padding defaults to PKCS1_PADDING. The encrypted string output can be decrypted using #private_decrypt.

Overloads:

  • #public_encrypt(string) ⇒ String

    Returns:

    • (String)
  • #public_encrypt(string, padding) ⇒ String

    Returns:

    • (String) 


423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 423

static VALUE
ossl_rsa_public_encrypt(int argc, VALUE *argv, VALUE self)
{
    RSA *rsa;
    const BIGNUM *rsa_n;
    int buf_len, pad;
    VALUE str, buffer, padding;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &rsa_n, NULL, NULL);
    if (!rsa_n)
	ossl_raise(eRSAError, "incomplete RSA");
    rb_scan_args(argc, argv, "11", &buffer, &padding);
    pad = (argc == 1) ? RSA_PKCS1_PADDING : NUM2INT(padding);
    StringValue(buffer);
    str = rb_str_new(0, RSA_size(rsa));
    buf_len = RSA_public_encrypt(RSTRING_LENINT(buffer), (unsigned char *)RSTRING_PTR(buffer),
				 (unsigned char *)RSTRING_PTR(str), rsa, pad);
    if (buf_len < 0) ossl_raise(eRSAError, NULL);
    rb_str_set_len(str, buf_len);

    return str;
}

#public_key ⇒ Object

Makes new RSA instance containing the public key from the private key.



809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 809

static VALUE
ossl_rsa_to_public_key(VALUE self)
{
    EVP_PKEY *pkey;
    RSA *rsa;
    VALUE obj;

    GetPKeyRSA(self, pkey);
    /* err check performed by rsa_instance */
    rsa = RSAPublicKey_dup(EVP_PKEY_get0_RSA(pkey));
    obj = rsa_instance(rb_obj_class(self), rsa);
    if (obj == Qfalse) {
	RSA_free(rsa);
	ossl_raise(eRSAError, NULL);
    }
    return obj;
}

#set_crt_params(dmp1, dmq1, iqmp) ⇒ self

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.

Returns:

  • (self)

#set_factors(p, q) ⇒ self

Sets p, q for the RSA instance.

Returns:

  • (self)

#set_key(n, e, d) ⇒ self

Sets n, e, d for the RSA instance.

Returns:

  • (self)

#sign_pss(digest, data, salt_length: , mgf1_hash: ) ⇒ String

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 = pkey.public_key
puts pub_key.verify_pss("SHA256", signature, data,
                        salt_length: :auto, mgf1_hash: "SHA256") # => true

Returns:

  • (String) 


580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 580

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);
}

#to_der ⇒ DER-format String

Outputs this keypair in DER encoding.

Returns:

  • (DER-format String) 


386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 386

static VALUE
ossl_rsa_to_der(VALUE self)
{
    RSA *rsa;
    const BIGNUM *n, *e, *d, *p, *q, *dmp1, *dmq1, *iqmp;
    int (*i2d_func)(const RSA *, unsigned char **);
    unsigned char *ptr;
    long len;
    VALUE str;

    GetRSA(self, rsa);
    RSA_get0_key(rsa, &n, &e, &d);
    RSA_get0_factors(rsa, &p, &q);
    RSA_get0_crt_params(rsa, &dmp1, &dmq1, &iqmp);
    if (n && e && d && p && q && dmp1 && dmq1 && iqmp)
	i2d_func = i2d_RSAPrivateKey;
    else
	i2d_func = (int (*)(const RSA *, unsigned char **))i2d_RSA_PUBKEY;
    if((len = i2d_func(rsa, NULL)) <= 0)
	ossl_raise(eRSAError, NULL);
    str = rb_str_new(0, len);
    ptr = (unsigned char *)RSTRING_PTR(str);
    if(i2d_func(rsa, &ptr) < 0)
	ossl_raise(eRSAError, NULL);
    ossl_str_adjust(str, ptr);

    return str;
}

#to_text ⇒ String

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

Dumps all parameters of a keypair to a String

Don’t use :-)) (It’s up to you)

Returns:

  • (String) 


783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 783

static VALUE
ossl_rsa_to_text(VALUE self)
{
    RSA *rsa;
    BIO *out;
    VALUE str;

    GetRSA(self, rsa);
    if (!(out = BIO_new(BIO_s_mem()))) {
	ossl_raise(eRSAError, NULL);
    }
    if (!RSA_print(out, rsa, 0)) { /* offset = 0 */
	BIO_free(out);
	ossl_raise(eRSAError, NULL);
    }
    str = ossl_membio2str(out);

    return str;
}

#verify_pss(digest, signature, data, salt_length: , mgf1_hash: ) ⇒ Object

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.



667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
 
# File 'ext/openssl/ossl_pkey_rsa.c', line 667

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);
}