1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
2  * project 2000.
3  */
4 /* ====================================================================
5  * Copyright (c) 2000-2005 The OpenSSL Project.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  *
19  * 3. All advertising materials mentioning features or use of this
20  *    software must display the following acknowledgment:
21  *    "This product includes software developed by the OpenSSL Project
22  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
23  *
24  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25  *    endorse or promote products derived from this software without
26  *    prior written permission. For written permission, please contact
27  *    licensing@OpenSSL.org.
28  *
29  * 5. Products derived from this software may not be called "OpenSSL"
30  *    nor may "OpenSSL" appear in their names without prior written
31  *    permission of the OpenSSL Project.
32  *
33  * 6. Redistributions of any form whatsoever must retain the following
34  *    acknowledgment:
35  *    "This product includes software developed by the OpenSSL Project
36  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
37  *
38  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
42  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49  * OF THE POSSIBILITY OF SUCH DAMAGE.
50  * ====================================================================
51  *
52  * This product includes cryptographic software written by Eric Young
53  * (eay@cryptsoft.com).  This product includes software written by Tim
54  * Hudson (tjh@cryptsoft.com). */
55 
56 #include <openssl/rsa.h>
57 
58 #include <assert.h>
59 #include <limits.h>
60 #include <string.h>
61 
62 #include <openssl/asn1.h>
63 #include <openssl/asn1t.h>
64 #include <openssl/bn.h>
65 #include <openssl/bytestring.h>
66 #include <openssl/err.h>
67 #include <openssl/mem.h>
68 
69 #include "internal.h"
70 
71 
parse_integer_buggy(CBS * cbs,BIGNUM ** out,int buggy)72 static int parse_integer_buggy(CBS *cbs, BIGNUM **out, int buggy) {
73   assert(*out == NULL);
74   *out = BN_new();
75   if (*out == NULL) {
76     return 0;
77   }
78   if (buggy) {
79     return BN_cbs2unsigned_buggy(cbs, *out);
80   }
81   return BN_cbs2unsigned(cbs, *out);
82 }
83 
parse_integer(CBS * cbs,BIGNUM ** out)84 static int parse_integer(CBS *cbs, BIGNUM **out) {
85   return parse_integer_buggy(cbs, out, 0 /* not buggy */);
86 }
87 
marshal_integer(CBB * cbb,BIGNUM * bn)88 static int marshal_integer(CBB *cbb, BIGNUM *bn) {
89   if (bn == NULL) {
90     /* An RSA object may be missing some components. */
91     OPENSSL_PUT_ERROR(RSA, RSA_R_VALUE_MISSING);
92     return 0;
93   }
94   return BN_bn2cbb(cbb, bn);
95 }
96 
parse_public_key(CBS * cbs,int buggy)97 static RSA *parse_public_key(CBS *cbs, int buggy) {
98   RSA *ret = RSA_new();
99   if (ret == NULL) {
100     return NULL;
101   }
102   CBS child;
103   if (!CBS_get_asn1(cbs, &child, CBS_ASN1_SEQUENCE) ||
104       !parse_integer_buggy(&child, &ret->n, buggy) ||
105       !parse_integer(&child, &ret->e) ||
106       CBS_len(&child) != 0) {
107     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
108     RSA_free(ret);
109     return NULL;
110   }
111 
112   if (!BN_is_odd(ret->e) ||
113       BN_num_bits(ret->e) < 2) {
114     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_RSA_PARAMETERS);
115     RSA_free(ret);
116     return NULL;
117   }
118 
119   return ret;
120 }
121 
RSA_parse_public_key(CBS * cbs)122 RSA *RSA_parse_public_key(CBS *cbs) {
123   return parse_public_key(cbs, 0 /* not buggy */);
124 }
125 
RSA_parse_public_key_buggy(CBS * cbs)126 RSA *RSA_parse_public_key_buggy(CBS *cbs) {
127   /* Estonian IDs issued between September 2014 to September 2015 are
128    * broken. See https://crbug.com/532048 and https://crbug.com/534766.
129    *
130    * TODO(davidben): Remove this code and callers in March 2016. */
131   return parse_public_key(cbs, 1 /* buggy */);
132 }
133 
RSA_public_key_from_bytes(const uint8_t * in,size_t in_len)134 RSA *RSA_public_key_from_bytes(const uint8_t *in, size_t in_len) {
135   CBS cbs;
136   CBS_init(&cbs, in, in_len);
137   RSA *ret = RSA_parse_public_key(&cbs);
138   if (ret == NULL || CBS_len(&cbs) != 0) {
139     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
140     RSA_free(ret);
141     return NULL;
142   }
143   return ret;
144 }
145 
RSA_marshal_public_key(CBB * cbb,const RSA * rsa)146 int RSA_marshal_public_key(CBB *cbb, const RSA *rsa) {
147   CBB child;
148   if (!CBB_add_asn1(cbb, &child, CBS_ASN1_SEQUENCE) ||
149       !marshal_integer(&child, rsa->n) ||
150       !marshal_integer(&child, rsa->e) ||
151       !CBB_flush(cbb)) {
152     OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
153     return 0;
154   }
155   return 1;
156 }
157 
RSA_public_key_to_bytes(uint8_t ** out_bytes,size_t * out_len,const RSA * rsa)158 int RSA_public_key_to_bytes(uint8_t **out_bytes, size_t *out_len,
159                             const RSA *rsa) {
160   CBB cbb;
161   CBB_zero(&cbb);
162   if (!CBB_init(&cbb, 0) ||
163       !RSA_marshal_public_key(&cbb, rsa) ||
164       !CBB_finish(&cbb, out_bytes, out_len)) {
165     OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
166     CBB_cleanup(&cbb);
167     return 0;
168   }
169   return 1;
170 }
171 
172 /* kVersionTwoPrime and kVersionMulti are the supported values of the version
173  * field of an RSAPrivateKey structure (RFC 3447). */
174 static const uint64_t kVersionTwoPrime = 0;
175 static const uint64_t kVersionMulti = 1;
176 
177 /* rsa_parse_additional_prime parses a DER-encoded OtherPrimeInfo from |cbs| and
178  * advances |cbs|. It returns a newly-allocated |RSA_additional_prime| on
179  * success or NULL on error. The |r| and |mont| fields of the result are set to
180  * NULL. */
rsa_parse_additional_prime(CBS * cbs)181 static RSA_additional_prime *rsa_parse_additional_prime(CBS *cbs) {
182   RSA_additional_prime *ret = OPENSSL_malloc(sizeof(RSA_additional_prime));
183   if (ret == NULL) {
184     OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
185     return 0;
186   }
187   memset(ret, 0, sizeof(RSA_additional_prime));
188 
189   CBS child;
190   if (!CBS_get_asn1(cbs, &child, CBS_ASN1_SEQUENCE) ||
191       !parse_integer(&child, &ret->prime) ||
192       !parse_integer(&child, &ret->exp) ||
193       !parse_integer(&child, &ret->coeff) ||
194       CBS_len(&child) != 0) {
195     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
196     RSA_additional_prime_free(ret);
197     return NULL;
198   }
199 
200   return ret;
201 }
202 
RSA_parse_private_key(CBS * cbs)203 RSA *RSA_parse_private_key(CBS *cbs) {
204   BN_CTX *ctx = NULL;
205   BIGNUM *product_of_primes_so_far = NULL;
206   RSA *ret = RSA_new();
207   if (ret == NULL) {
208     return NULL;
209   }
210 
211   CBS child;
212   uint64_t version;
213   if (!CBS_get_asn1(cbs, &child, CBS_ASN1_SEQUENCE) ||
214       !CBS_get_asn1_uint64(&child, &version)) {
215     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
216     goto err;
217   }
218 
219   if (version != kVersionTwoPrime && version != kVersionMulti) {
220     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_VERSION);
221     goto err;
222   }
223 
224   if (!parse_integer(&child, &ret->n) ||
225       !parse_integer(&child, &ret->e) ||
226       !parse_integer(&child, &ret->d) ||
227       !parse_integer(&child, &ret->p) ||
228       !parse_integer(&child, &ret->q) ||
229       !parse_integer(&child, &ret->dmp1) ||
230       !parse_integer(&child, &ret->dmq1) ||
231       !parse_integer(&child, &ret->iqmp)) {
232     goto err;
233   }
234 
235   /* Multi-prime RSA requires a newer version. */
236   if (version == kVersionMulti &&
237       CBS_peek_asn1_tag(&child, CBS_ASN1_SEQUENCE)) {
238     CBS other_prime_infos;
239     if (!CBS_get_asn1(&child, &other_prime_infos, CBS_ASN1_SEQUENCE) ||
240         CBS_len(&other_prime_infos) == 0) {
241       OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
242       goto err;
243     }
244     ret->additional_primes = sk_RSA_additional_prime_new_null();
245     if (ret->additional_primes == NULL) {
246       OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
247       goto err;
248     }
249 
250     ctx = BN_CTX_new();
251     product_of_primes_so_far = BN_new();
252     if (ctx == NULL ||
253         product_of_primes_so_far == NULL ||
254         !BN_mul(product_of_primes_so_far, ret->p, ret->q, ctx)) {
255       goto err;
256     }
257 
258     while (CBS_len(&other_prime_infos) > 0) {
259       RSA_additional_prime *ap = rsa_parse_additional_prime(&other_prime_infos);
260       if (ap == NULL) {
261         goto err;
262       }
263       if (!sk_RSA_additional_prime_push(ret->additional_primes, ap)) {
264         OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
265         RSA_additional_prime_free(ap);
266         goto err;
267       }
268       ap->r = BN_dup(product_of_primes_so_far);
269       if (ap->r == NULL ||
270           !BN_mul(product_of_primes_so_far, product_of_primes_so_far,
271                   ap->prime, ctx)) {
272         goto err;
273       }
274     }
275   }
276 
277   if (CBS_len(&child) != 0) {
278     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
279     goto err;
280   }
281 
282   BN_CTX_free(ctx);
283   BN_free(product_of_primes_so_far);
284   return ret;
285 
286 err:
287   BN_CTX_free(ctx);
288   BN_free(product_of_primes_so_far);
289   RSA_free(ret);
290   return NULL;
291 }
292 
RSA_private_key_from_bytes(const uint8_t * in,size_t in_len)293 RSA *RSA_private_key_from_bytes(const uint8_t *in, size_t in_len) {
294   CBS cbs;
295   CBS_init(&cbs, in, in_len);
296   RSA *ret = RSA_parse_private_key(&cbs);
297   if (ret == NULL || CBS_len(&cbs) != 0) {
298     OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_ENCODING);
299     RSA_free(ret);
300     return NULL;
301   }
302   return ret;
303 }
304 
RSA_marshal_private_key(CBB * cbb,const RSA * rsa)305 int RSA_marshal_private_key(CBB *cbb, const RSA *rsa) {
306   const int is_multiprime =
307       sk_RSA_additional_prime_num(rsa->additional_primes) > 0;
308 
309   CBB child;
310   if (!CBB_add_asn1(cbb, &child, CBS_ASN1_SEQUENCE) ||
311       !CBB_add_asn1_uint64(&child,
312                            is_multiprime ? kVersionMulti : kVersionTwoPrime) ||
313       !marshal_integer(&child, rsa->n) ||
314       !marshal_integer(&child, rsa->e) ||
315       !marshal_integer(&child, rsa->d) ||
316       !marshal_integer(&child, rsa->p) ||
317       !marshal_integer(&child, rsa->q) ||
318       !marshal_integer(&child, rsa->dmp1) ||
319       !marshal_integer(&child, rsa->dmq1) ||
320       !marshal_integer(&child, rsa->iqmp)) {
321     OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
322     return 0;
323   }
324 
325   if (is_multiprime) {
326     CBB other_prime_infos;
327     if (!CBB_add_asn1(&child, &other_prime_infos, CBS_ASN1_SEQUENCE)) {
328       OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
329       return 0;
330     }
331     size_t i;
332     for (i = 0; i < sk_RSA_additional_prime_num(rsa->additional_primes); i++) {
333       RSA_additional_prime *ap =
334               sk_RSA_additional_prime_value(rsa->additional_primes, i);
335       CBB other_prime_info;
336       if (!CBB_add_asn1(&other_prime_infos, &other_prime_info,
337                         CBS_ASN1_SEQUENCE) ||
338           !marshal_integer(&other_prime_info, ap->prime) ||
339           !marshal_integer(&other_prime_info, ap->exp) ||
340           !marshal_integer(&other_prime_info, ap->coeff)) {
341         OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
342         return 0;
343       }
344     }
345   }
346 
347   if (!CBB_flush(cbb)) {
348     OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
349     return 0;
350   }
351   return 1;
352 }
353 
RSA_private_key_to_bytes(uint8_t ** out_bytes,size_t * out_len,const RSA * rsa)354 int RSA_private_key_to_bytes(uint8_t **out_bytes, size_t *out_len,
355                              const RSA *rsa) {
356   CBB cbb;
357   CBB_zero(&cbb);
358   if (!CBB_init(&cbb, 0) ||
359       !RSA_marshal_private_key(&cbb, rsa) ||
360       !CBB_finish(&cbb, out_bytes, out_len)) {
361     OPENSSL_PUT_ERROR(RSA, RSA_R_ENCODE_ERROR);
362     CBB_cleanup(&cbb);
363     return 0;
364   }
365   return 1;
366 }
367 
d2i_RSAPublicKey(RSA ** out,const uint8_t ** inp,long len)368 RSA *d2i_RSAPublicKey(RSA **out, const uint8_t **inp, long len) {
369   if (len < 0) {
370     return NULL;
371   }
372   CBS cbs;
373   CBS_init(&cbs, *inp, (size_t)len);
374   RSA *ret = RSA_parse_public_key(&cbs);
375   if (ret == NULL) {
376     return NULL;
377   }
378   if (out != NULL) {
379     RSA_free(*out);
380     *out = ret;
381   }
382   *inp += (size_t)len - CBS_len(&cbs);
383   return ret;
384 }
385 
i2d_RSAPublicKey(const RSA * in,uint8_t ** outp)386 int i2d_RSAPublicKey(const RSA *in, uint8_t **outp) {
387   uint8_t *der;
388   size_t der_len;
389   if (!RSA_public_key_to_bytes(&der, &der_len, in)) {
390     return -1;
391   }
392   if (der_len > INT_MAX) {
393     OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
394     OPENSSL_free(der);
395     return -1;
396   }
397   if (outp != NULL) {
398     if (*outp == NULL) {
399       *outp = der;
400       der = NULL;
401     } else {
402       memcpy(*outp, der, der_len);
403       *outp += der_len;
404     }
405   }
406   OPENSSL_free(der);
407   return (int)der_len;
408 }
409 
d2i_RSAPrivateKey(RSA ** out,const uint8_t ** inp,long len)410 RSA *d2i_RSAPrivateKey(RSA **out, const uint8_t **inp, long len) {
411   if (len < 0) {
412     return NULL;
413   }
414   CBS cbs;
415   CBS_init(&cbs, *inp, (size_t)len);
416   RSA *ret = RSA_parse_private_key(&cbs);
417   if (ret == NULL) {
418     return NULL;
419   }
420   if (out != NULL) {
421     RSA_free(*out);
422     *out = ret;
423   }
424   *inp += (size_t)len - CBS_len(&cbs);
425   return ret;
426 }
427 
i2d_RSAPrivateKey(const RSA * in,uint8_t ** outp)428 int i2d_RSAPrivateKey(const RSA *in, uint8_t **outp) {
429   uint8_t *der;
430   size_t der_len;
431   if (!RSA_private_key_to_bytes(&der, &der_len, in)) {
432     return -1;
433   }
434   if (der_len > INT_MAX) {
435     OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
436     OPENSSL_free(der);
437     return -1;
438   }
439   if (outp != NULL) {
440     if (*outp == NULL) {
441       *outp = der;
442       der = NULL;
443     } else {
444       memcpy(*outp, der, der_len);
445       *outp += der_len;
446     }
447   }
448   OPENSSL_free(der);
449   return (int)der_len;
450 }
451 
452 ASN1_SEQUENCE(RSA_PSS_PARAMS) = {
453   ASN1_EXP_OPT(RSA_PSS_PARAMS, hashAlgorithm, X509_ALGOR,0),
454   ASN1_EXP_OPT(RSA_PSS_PARAMS, maskGenAlgorithm, X509_ALGOR,1),
455   ASN1_EXP_OPT(RSA_PSS_PARAMS, saltLength, ASN1_INTEGER,2),
456   ASN1_EXP_OPT(RSA_PSS_PARAMS, trailerField, ASN1_INTEGER,3),
457 } ASN1_SEQUENCE_END(RSA_PSS_PARAMS);
458 
459 IMPLEMENT_ASN1_FUNCTIONS(RSA_PSS_PARAMS);
460 
RSAPublicKey_dup(const RSA * rsa)461 RSA *RSAPublicKey_dup(const RSA *rsa) {
462   uint8_t *der;
463   size_t der_len;
464   if (!RSA_public_key_to_bytes(&der, &der_len, rsa)) {
465     return NULL;
466   }
467   RSA *ret = RSA_public_key_from_bytes(der, der_len);
468   OPENSSL_free(der);
469   return ret;
470 }
471 
RSAPrivateKey_dup(const RSA * rsa)472 RSA *RSAPrivateKey_dup(const RSA *rsa) {
473   uint8_t *der;
474   size_t der_len;
475   if (!RSA_private_key_to_bytes(&der, &der_len, rsa)) {
476     return NULL;
477   }
478   RSA *ret = RSA_private_key_from_bytes(der, der_len);
479   OPENSSL_free(der);
480   return ret;
481 }
482