aboutsummaryrefslogtreecommitdiffstats
path: root/src/lib/pubkey/pkcs8.cpp
blob: 8d3eba6dc742912d5ef7b927bbbb96700452a89d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
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
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
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
379
380
381
382
383
384
385
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
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
/*
* PKCS #8
* (C) 1999-2010,2014,2018 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include <botan/pkcs8.h>
#include <botan/rng.h>
#include <botan/der_enc.h>
#include <botan/ber_dec.h>
#include <botan/alg_id.h>
#include <botan/oids.h>
#include <botan/pem.h>
#include <botan/scan_name.h>
#include <botan/pk_algs.h>

#if defined(BOTAN_HAS_PKCS5_PBES2)
   #include <botan/pbes2.h>
#endif

namespace Botan {

namespace PKCS8 {

namespace {

/*
* Get info from an EncryptedPrivateKeyInfo
*/
secure_vector<uint8_t> PKCS8_extract(DataSource& source,
                                  AlgorithmIdentifier& pbe_alg_id)
   {
   secure_vector<uint8_t> key_data;

   BER_Decoder(source)
      .start_cons(SEQUENCE)
         .decode(pbe_alg_id)
         .decode(key_data, OCTET_STRING)
      .verify_end();

   return key_data;
   }

/*
* PEM decode and/or decrypt a private key
*/
secure_vector<uint8_t> PKCS8_decode(
   DataSource& source,
   std::function<std::string ()> get_passphrase,
   AlgorithmIdentifier& pk_alg_id,
   bool is_encrypted)
   {
   AlgorithmIdentifier pbe_alg_id;
   secure_vector<uint8_t> key_data, key;

   try {
      if(ASN1::maybe_BER(source) && !PEM_Code::matches(source))
         {
         if(is_encrypted)
            {
            key_data = PKCS8_extract(source, pbe_alg_id);
            }
         else
            {
            // todo read more efficiently
            while(!source.end_of_data())
               {
               uint8_t b;
               size_t read = source.read_byte(b);
               if(read)
                  {
                  key_data.push_back(b);
                  }
               }
            }
         }
      else
         {
         std::string label;
         key_data = PEM_Code::decode(source, label);

         // todo remove autodetect for pem as well?
         if(label == "PRIVATE KEY")
            is_encrypted = false;
         else if(label == "ENCRYPTED PRIVATE KEY")
            {
            DataSource_Memory key_source(key_data);
            key_data = PKCS8_extract(key_source, pbe_alg_id);
            }
         else
            throw PKCS8_Exception("Unknown PEM label " + label);
         }

      if(key_data.empty())
         throw PKCS8_Exception("No key data found");
      }
   catch(Decoding_Error& e)
      {
      throw Decoding_Error("PKCS #8 private key decoding failed: " + std::string(e.what()));
      }

   try
      {
      if(is_encrypted)
         {
         if(OIDS::lookup(pbe_alg_id.get_oid()) != "PBE-PKCS5v20")
            throw Exception("Unknown PBE type " + pbe_alg_id.get_oid().as_string());
#if defined(BOTAN_HAS_PKCS5_PBES2)
         key = pbes2_decrypt(key_data, get_passphrase(), pbe_alg_id.get_parameters());
#else
         BOTAN_UNUSED(get_passphrase);
         throw Decoding_Error("Private key is encrypted but PBES2 was disabled in build");
#endif
         }
      else
         key = key_data;

      BER_Decoder(key)
         .start_cons(SEQUENCE)
            .decode_and_check<size_t>(0, "Unknown PKCS #8 version number")
            .decode(pk_alg_id)
            .decode(key, OCTET_STRING)
            .discard_remaining()
         .end_cons();
      }
   catch(std::exception& e)
      {
      throw Decoding_Error("PKCS #8 private key decoding failed: " + std::string(e.what()));
      }
   return key;
   }

}

/*
* BER encode a PKCS #8 private key, unencrypted
*/
secure_vector<uint8_t> BER_encode(const Private_Key& key)
   {
   // keeping around for compat
   return key.private_key_info();
   }

/*
* PEM encode a PKCS #8 private key, unencrypted
*/
std::string PEM_encode(const Private_Key& key)
   {
   return PEM_Code::encode(PKCS8::BER_encode(key), "PRIVATE KEY");
   }

#if defined(BOTAN_HAS_PKCS5_PBES2)

namespace {

std::pair<std::string, std::string>
choose_pbe_params(const std::string& pbe_algo, const std::string& key_algo)
   {
   if(pbe_algo.empty())
      {
      // Defaults:
      if(key_algo == "Curve25519" || key_algo == "McEliece")
         return std::make_pair("AES-256/GCM", "SHA-512");
      else // for everything else (RSA, DSA, ECDSA, GOST, ...)
         return std::make_pair("AES-256/CBC", "SHA-256");
      }

   SCAN_Name request(pbe_algo);
   if(request.algo_name() != "PBE-PKCS5v20" || request.arg_count() != 2)
      throw Exception("Unsupported PBE " + pbe_algo);
   return std::make_pair(request.arg(0), request.arg(1));
   }

}

#endif

/*
* BER encode a PKCS #8 private key, encrypted
*/
std::vector<uint8_t> BER_encode(const Private_Key& key,
                             RandomNumberGenerator& rng,
                             const std::string& pass,
                             std::chrono::milliseconds msec,
                             const std::string& pbe_algo)
   {
#if defined(BOTAN_HAS_PKCS5_PBES2)
   const auto pbe_params = choose_pbe_params(pbe_algo, key.algo_name());

   const std::pair<AlgorithmIdentifier, std::vector<uint8_t>> pbe_info =
      pbes2_encrypt_msec(PKCS8::BER_encode(key), pass, msec, nullptr,
                         pbe_params.first, pbe_params.second, rng);

   std::vector<uint8_t> output;
   DER_Encoder der(output);
   der.start_cons(SEQUENCE)
         .encode(pbe_info.first)
         .encode(pbe_info.second, OCTET_STRING)
      .end_cons();

   return output;
#else
   BOTAN_UNUSED(key, rng, pass, msec, pbe_algo);
   throw Encoding_Error("PKCS8::BER_encode cannot encrypt because PBES2 was disabled in build");
#endif
   }

/*
* PEM encode a PKCS #8 private key, encrypted
*/
std::string PEM_encode(const Private_Key& key,
                       RandomNumberGenerator& rng,
                       const std::string& pass,
                       std::chrono::milliseconds msec,
                       const std::string& pbe_algo)
   {
   if(pass.empty())
      return PEM_encode(key);

   return PEM_Code::encode(PKCS8::BER_encode(key, rng, pass, msec, pbe_algo),
                           "ENCRYPTED PRIVATE KEY");
   }

/*
* BER encode a PKCS #8 private key, encrypted
*/
std::vector<uint8_t> BER_encode_encrypted_pbkdf_iter(const Private_Key& key,
                                                     RandomNumberGenerator& rng,
                                                     const std::string& pass,
                                                     size_t pbkdf_iterations,
                                                     const std::string& cipher,
                                                     const std::string& pbkdf_hash)
   {
#if defined(BOTAN_HAS_PKCS5_PBES2)
   const std::pair<AlgorithmIdentifier, std::vector<uint8_t>> pbe_info =
      pbes2_encrypt_iter(key.private_key_info(),
                         pass, pbkdf_iterations,
                         cipher.empty() ? "AES-256/CBC" : cipher,
                         pbkdf_hash.empty() ? "SHA-256" : pbkdf_hash,
                         rng);

   std::vector<uint8_t> output;
   DER_Encoder der(output);
   der.start_cons(SEQUENCE)
         .encode(pbe_info.first)
         .encode(pbe_info.second, OCTET_STRING)
      .end_cons();

   return output;

#else
   BOTAN_UNUSED(key, rng, pass, pbkdf_iterations, cipher, pbkdf_hash);
   throw Encoding_Error("PKCS8::BER_encode_encrypted_pbkdf_iter cannot encrypt because PBES2 disabled in build");
#endif
   }

/*
* PEM encode a PKCS #8 private key, encrypted
*/
std::string PEM_encode_encrypted_pbkdf_iter(const Private_Key& key,
                                            RandomNumberGenerator& rng,
                                            const std::string& pass,
                                            size_t pbkdf_iterations,
                                            const std::string& cipher,
                                            const std::string& pbkdf_hash)
   {
   return PEM_Code::encode(
      PKCS8::BER_encode_encrypted_pbkdf_iter(key, rng, pass, pbkdf_iterations, cipher, pbkdf_hash),
      "ENCRYPTED PRIVATE KEY");
   }

/*
* BER encode a PKCS #8 private key, encrypted
*/
std::vector<uint8_t> BER_encode_encrypted_pbkdf_msec(const Private_Key& key,
                                                     RandomNumberGenerator& rng,
                                                     const std::string& pass,
                                                     std::chrono::milliseconds pbkdf_msec,
                                                     size_t* pbkdf_iterations,
                                                     const std::string& cipher,
                                                     const std::string& pbkdf_hash)
   {
#if defined(BOTAN_HAS_PKCS5_PBES2)
   const std::pair<AlgorithmIdentifier, std::vector<uint8_t>> pbe_info =
      pbes2_encrypt_msec(key.private_key_info(), pass,
                         pbkdf_msec, pbkdf_iterations,
                         cipher.empty() ? "AES-256/CBC" : cipher,
                         pbkdf_hash.empty() ? "SHA-256" : pbkdf_hash,
                         rng);

   std::vector<uint8_t> output;
   DER_Encoder(output)
      .start_cons(SEQUENCE)
         .encode(pbe_info.first)
         .encode(pbe_info.second, OCTET_STRING)
      .end_cons();

   return output;
#else
   BOTAN_UNUSED(key, rng, pass, pbkdf_msec, pbkdf_iterations, cipher, pbkdf_hash);
   throw Encoding_Error("BER_encode_encrypted_pbkdf_msec cannot encrypt because PBES2 disabled in build");
#endif
   }

/*
* PEM encode a PKCS #8 private key, encrypted
*/
std::string PEM_encode_encrypted_pbkdf_msec(const Private_Key& key,
                                            RandomNumberGenerator& rng,
                                            const std::string& pass,
                                            std::chrono::milliseconds pbkdf_msec,
                                            size_t* pbkdf_iterations,
                                            const std::string& cipher,
                                            const std::string& pbkdf_hash)
   {
   return PEM_Code::encode(
      PKCS8::BER_encode_encrypted_pbkdf_msec(key, rng, pass, pbkdf_msec, pbkdf_iterations, cipher, pbkdf_hash),
      "ENCRYPTED PRIVATE KEY");
   }

namespace {

/*
* Extract a private key (encrypted/unencrypted) and return it
*/
std::unique_ptr<Private_Key>
load_key(DataSource& source,
         std::function<std::string ()> get_pass,
         bool is_encrypted)
   {
   AlgorithmIdentifier alg_id;
   secure_vector<uint8_t> pkcs8_key = PKCS8_decode(source, get_pass, alg_id, is_encrypted);

   const std::string alg_name = OIDS::lookup(alg_id.get_oid());
   if(alg_name.empty() || alg_name == alg_id.get_oid().as_string())
      throw PKCS8_Exception("Unknown algorithm OID: " +
                            alg_id.get_oid().as_string());

   return load_private_key(alg_id, pkcs8_key);
   }

}

/*
* Extract an encrypted private key and return it
*/
std::unique_ptr<Private_Key> load_key(DataSource& source,
                      std::function<std::string ()> get_pass)
   {
   return load_key(source, get_pass, true);
   }

/*
* Extract an encrypted private key and return it
*/
std::unique_ptr<Private_Key> load_key(DataSource& source,
                      const std::string& pass)
   {
   return load_key(source, [pass]() { return pass; }, true);
   }

/*
* Extract an unencrypted private key and return it
*/
std::unique_ptr<Private_Key> load_key(DataSource& source)
   {
   auto fail_fn = []() -> std::string {
      throw PKCS8_Exception("Internal error: Attempt to read password for unencrypted key");
   };

   return load_key(source, fail_fn, false);
   }

/*
* Make a copy of this private key
*/
std::unique_ptr<Private_Key> copy_key(const Private_Key& key)
   {
   DataSource_Memory source(PEM_encode(key));
   return PKCS8::load_key(source);
   }

/*
* Extract an encrypted private key and return it
*/
Private_Key* load_key(DataSource& source,
                      RandomNumberGenerator& rng,
                      std::function<std::string ()> get_pass)
   {
   BOTAN_UNUSED(rng);
   return PKCS8::load_key(source, get_pass).release();
   }

/*
* Extract an encrypted private key and return it
*/
Private_Key* load_key(DataSource& source,
                      RandomNumberGenerator& rng,
                      const std::string& pass)
   {
   BOTAN_UNUSED(rng);
   return PKCS8::load_key(source, pass).release();
   }

/*
* Extract an unencrypted private key and return it
*/
Private_Key* load_key(DataSource& source,
                      RandomNumberGenerator& rng)
   {
   BOTAN_UNUSED(rng);
   return PKCS8::load_key(source).release();
   }

#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)

/*
* Extract an encrypted private key and return it
*/
Private_Key* load_key(const std::string& fsname,
                      RandomNumberGenerator& rng,
                      std::function<std::string ()> get_pass)
   {
   BOTAN_UNUSED(rng);
   DataSource_Stream in(fsname);
   return PKCS8::load_key(in, get_pass).release();
   }

/*
* Extract an encrypted private key and return it
*/
Private_Key* load_key(const std::string& fsname,
                      RandomNumberGenerator& rng,
                      const std::string& pass)
   {
   BOTAN_UNUSED(rng);
   DataSource_Stream in(fsname);
   return PKCS8::load_key(in, [pass]() { return pass; }).release();
   }

/*
* Extract an unencrypted private key and return it
*/
Private_Key* load_key(const std::string& fsname,
                      RandomNumberGenerator& rng)
   {
   BOTAN_UNUSED(rng);
   DataSource_Stream in(fsname);
   return PKCS8::load_key(in).release();
   }
#endif

/*
* Make a copy of this private key
*/
Private_Key* copy_key(const Private_Key& key,
                      RandomNumberGenerator& rng)
   {
   BOTAN_UNUSED(rng);
   return PKCS8::copy_key(key).release();
   }



}

}