File: keyraw.c

package info (click to toggle)
unbound 1.6.0-2~bpo8+1
  • links: PTS, VCS
  • area: main
  • in suites: jessie-backports
  • size: 20,444 kB
  • sloc: ansic: 79,862; sh: 5,040; yacc: 1,900; makefile: 1,315; python: 1,302; perl: 141
file content (408 lines) | stat: -rw-r--r-- 8,740 bytes parent folder | download | duplicates (2)
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
/*
 * keyraw.c - raw key operations and conversions
 *
 * (c) NLnet Labs, 2004-2008
 *
 * See the file LICENSE for the license
 */
/**
 * \file
 * Implementation of raw DNSKEY functions (work on wire rdata).
 */

#include "config.h"
#include "sldns/keyraw.h"
#include "sldns/rrdef.h"

#ifdef HAVE_SSL
#include <openssl/ssl.h>
#include <openssl/evp.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#include <openssl/md5.h>
#ifdef HAVE_OPENSSL_ENGINE_H
#  include <openssl/engine.h>
#endif
#ifdef HAVE_OPENSSL_BN_H
#include <openssl/bn.h>
#endif
#ifdef HAVE_OPENSSL_RSA_H
#include <openssl/rsa.h>
#endif
#ifdef HAVE_OPENSSL_DSA_H
#include <openssl/dsa.h>
#endif
#endif /* HAVE_SSL */

size_t
sldns_rr_dnskey_key_size_raw(const unsigned char* keydata,
	const size_t len, int alg)
{
	/* for DSA keys */
	uint8_t t;
	
	/* for RSA keys */
	uint16_t exp;
	uint16_t int16;
	
	switch ((sldns_algorithm)alg) {
	case LDNS_DSA:
	case LDNS_DSA_NSEC3:
		if (len > 0) {
			t = keydata[0];
			return (64 + t*8)*8;
		} else {
			return 0;
		}
		break;
	case LDNS_RSAMD5:
	case LDNS_RSASHA1:
	case LDNS_RSASHA1_NSEC3:
#ifdef USE_SHA2
	case LDNS_RSASHA256:
	case LDNS_RSASHA512:
#endif
		if (len > 0) {
			if (keydata[0] == 0) {
				/* big exponent */
				if (len > 3) {
					memmove(&int16, keydata + 1, 2);
					exp = ntohs(int16);
					return (len - exp - 3)*8;
				} else {
					return 0;
				}
			} else {
				exp = keydata[0];
				return (len-exp-1)*8;
			}
		} else {
			return 0;
		}
		break;
#ifdef USE_GOST
	case LDNS_ECC_GOST:
		return 512;
#endif
#ifdef USE_ECDSA
        case LDNS_ECDSAP256SHA256:
                return 256;
        case LDNS_ECDSAP384SHA384:
                return 384;
#endif
	default:
		return 0;
	}
}

uint16_t sldns_calc_keytag_raw(uint8_t* key, size_t keysize)
{
	if(keysize < 4) {
		return 0;
	}
	/* look at the algorithm field, copied from 2535bis */
	if (key[3] == LDNS_RSAMD5) {
		uint16_t ac16 = 0;
		if (keysize > 4) {
			memmove(&ac16, key + keysize - 3, 2);
		}
		ac16 = ntohs(ac16);
		return (uint16_t) ac16;
	} else {
		size_t i;
		uint32_t ac32 = 0;
		for (i = 0; i < keysize; ++i) {
			ac32 += (i & 1) ? key[i] : key[i] << 8;
		}
		ac32 += (ac32 >> 16) & 0xFFFF;
		return (uint16_t) (ac32 & 0xFFFF);
	}
}

#ifdef HAVE_SSL
#ifdef USE_GOST
/** store GOST engine reference loaded into OpenSSL library */
ENGINE* sldns_gost_engine = NULL;

int
sldns_key_EVP_load_gost_id(void)
{
	static int gost_id = 0;
	const EVP_PKEY_ASN1_METHOD* meth;
	ENGINE* e;

	if(gost_id) return gost_id;

	/* see if configuration loaded gost implementation from other engine*/
	meth = EVP_PKEY_asn1_find_str(NULL, "gost2001", -1);
	if(meth) {
		EVP_PKEY_asn1_get0_info(&gost_id, NULL, NULL, NULL, NULL, meth);
		return gost_id;
	}

	/* see if engine can be loaded already */
	e = ENGINE_by_id("gost");
	if(!e) {
		/* load it ourself, in case statically linked */
		ENGINE_load_builtin_engines();
		ENGINE_load_dynamic();
		e = ENGINE_by_id("gost");
	}
	if(!e) {
		/* no gost engine in openssl */
		return 0;
	}
	if(!ENGINE_set_default(e, ENGINE_METHOD_ALL)) {
		ENGINE_finish(e);
		ENGINE_free(e);
		return 0;
	}

	meth = EVP_PKEY_asn1_find_str(&e, "gost2001", -1);
	if(!meth) {
		/* algo not found */
		ENGINE_finish(e);
		ENGINE_free(e);
		return 0;
	}
        /* Note: do not ENGINE_finish and ENGINE_free the acquired engine
         * on some platforms this frees up the meth and unloads gost stuff */
        sldns_gost_engine = e;
	
	EVP_PKEY_asn1_get0_info(&gost_id, NULL, NULL, NULL, NULL, meth);
	return gost_id;
} 

void sldns_key_EVP_unload_gost(void)
{
        if(sldns_gost_engine) {
                ENGINE_finish(sldns_gost_engine);
                ENGINE_free(sldns_gost_engine);
                sldns_gost_engine = NULL;
        }
}
#endif /* USE_GOST */

DSA *
sldns_key_buf2dsa_raw(unsigned char* key, size_t len)
{
	uint8_t T;
	uint16_t length;
	uint16_t offset;
	DSA *dsa;
	BIGNUM *Q; BIGNUM *P;
	BIGNUM *G; BIGNUM *Y;

	if(len == 0)
		return NULL;
	T = (uint8_t)key[0];
	length = (64 + T * 8);
	offset = 1;

	if (T > 8) {
		return NULL;
	}
	if(len < (size_t)1 + SHA_DIGEST_LENGTH + 3*length)
		return NULL;

	Q = BN_bin2bn(key+offset, SHA_DIGEST_LENGTH, NULL);
	offset += SHA_DIGEST_LENGTH;

	P = BN_bin2bn(key+offset, (int)length, NULL);
	offset += length;

	G = BN_bin2bn(key+offset, (int)length, NULL);
	offset += length;

	Y = BN_bin2bn(key+offset, (int)length, NULL);

	/* create the key and set its properties */
	if(!Q || !P || !G || !Y || !(dsa = DSA_new())) {
		BN_free(Q);
		BN_free(P);
		BN_free(G);
		BN_free(Y);
		return NULL;
	}
#if OPENSSL_VERSION_NUMBER < 0x10100000 || defined(HAVE_LIBRESSL)
#ifndef S_SPLINT_S
	dsa->p = P;
	dsa->q = Q;
	dsa->g = G;
	dsa->pub_key = Y;
#endif /* splint */

#else /* OPENSSL_VERSION_NUMBER */
	if (!DSA_set0_pqg(dsa, P, Q, G)) {
		/* QPG not yet attached, need to free */
		BN_free(Q);
		BN_free(P);
		BN_free(G);

		DSA_free(dsa);
		BN_free(Y);
		return NULL;
	}
	if (!DSA_set0_key(dsa, Y, NULL)) {
		/* QPG attached, cleaned up by DSA_fre() */
		DSA_free(dsa);
		BN_free(Y);
		return NULL;
	}
#endif

	return dsa;
}

RSA *
sldns_key_buf2rsa_raw(unsigned char* key, size_t len)
{
	uint16_t offset;
	uint16_t exp;
	uint16_t int16;
	RSA *rsa;
	BIGNUM *modulus;
	BIGNUM *exponent;

	if (len == 0)
		return NULL;
	if (key[0] == 0) {
		if(len < 3)
			return NULL;
		memmove(&int16, key+1, 2);
		exp = ntohs(int16);
		offset = 3;
	} else {
		exp = key[0];
		offset = 1;
	}

	/* key length at least one */
	if(len < (size_t)offset + exp + 1)
		return NULL;

	/* Exponent */
	exponent = BN_new();
	if(!exponent) return NULL;
	(void) BN_bin2bn(key+offset, (int)exp, exponent);
	offset += exp;

	/* Modulus */
	modulus = BN_new();
	if(!modulus) {
		BN_free(exponent);
		return NULL;
	}
	/* length of the buffer must match the key length! */
	(void) BN_bin2bn(key+offset, (int)(len - offset), modulus);

	rsa = RSA_new();
	if(!rsa) {
		BN_free(exponent);
		BN_free(modulus);
		return NULL;
	}
#if OPENSSL_VERSION_NUMBER < 0x10100000 || defined(HAVE_LIBRESSL)
#ifndef S_SPLINT_S
	rsa->n = modulus;
	rsa->e = exponent;
#endif /* splint */

#else /* OPENSSL_VERSION_NUMBER */
	if (!RSA_set0_key(rsa, modulus, exponent, NULL)) {
		BN_free(exponent);
		BN_free(modulus);
		RSA_free(rsa);
		return NULL;
	}
#endif

	return rsa;
}

#ifdef USE_GOST
EVP_PKEY*
sldns_gost2pkey_raw(unsigned char* key, size_t keylen)
{
	/* prefix header for X509 encoding */
	uint8_t asn[37] = { 0x30, 0x63, 0x30, 0x1c, 0x06, 0x06, 0x2a, 0x85, 
		0x03, 0x02, 0x02, 0x13, 0x30, 0x12, 0x06, 0x07, 0x2a, 0x85, 
		0x03, 0x02, 0x02, 0x23, 0x01, 0x06, 0x07, 0x2a, 0x85, 0x03, 
		0x02, 0x02, 0x1e, 0x01, 0x03, 0x43, 0x00, 0x04, 0x40};
	unsigned char encoded[37+64];
	const unsigned char* pp;
	if(keylen != 64) {
		/* key wrong size */
		return NULL;
	}

	/* create evp_key */
	memmove(encoded, asn, 37);
	memmove(encoded+37, key, 64);
	pp = (unsigned char*)&encoded[0];

	return d2i_PUBKEY(NULL, &pp, (int)sizeof(encoded));
}
#endif /* USE_GOST */

#ifdef USE_ECDSA
EVP_PKEY*
sldns_ecdsa2pkey_raw(unsigned char* key, size_t keylen, uint8_t algo)
{
	unsigned char buf[256+2]; /* sufficient for 2*384/8+1 */
        const unsigned char* pp = buf;
        EVP_PKEY *evp_key;
        EC_KEY *ec;
	/* check length, which uncompressed must be 2 bignums */
        if(algo == LDNS_ECDSAP256SHA256) {
		if(keylen != 2*256/8) return NULL;
                ec = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
        } else if(algo == LDNS_ECDSAP384SHA384) {
		if(keylen != 2*384/8) return NULL;
                ec = EC_KEY_new_by_curve_name(NID_secp384r1);
        } else    ec = NULL;
        if(!ec) return NULL;
	if(keylen+1 > sizeof(buf)) { /* sanity check */
                EC_KEY_free(ec);
		return NULL;
	}
	/* prepend the 0x02 (from docs) (or actually 0x04 from implementation
	 * of openssl) for uncompressed data */
	buf[0] = POINT_CONVERSION_UNCOMPRESSED;
	memmove(buf+1, key, keylen);
        if(!o2i_ECPublicKey(&ec, &pp, (int)keylen+1)) {
                EC_KEY_free(ec);
                return NULL;
        }
        evp_key = EVP_PKEY_new();
        if(!evp_key) {
                EC_KEY_free(ec);
                return NULL;
        }
        if (!EVP_PKEY_assign_EC_KEY(evp_key, ec)) {
		EVP_PKEY_free(evp_key);
		EC_KEY_free(ec);
		return NULL;
	}
        return evp_key;
}
#endif /* USE_ECDSA */

int
sldns_digest_evp(unsigned char* data, unsigned int len, unsigned char* dest,
	const EVP_MD* md)
{
	EVP_MD_CTX* ctx;
	ctx = EVP_MD_CTX_create();
	if(!ctx)
		return 0;
	if(!EVP_DigestInit_ex(ctx, md, NULL) ||
		!EVP_DigestUpdate(ctx, data, len) ||
		!EVP_DigestFinal_ex(ctx, dest, NULL)) {
		EVP_MD_CTX_destroy(ctx);
		return 0;
	}
	EVP_MD_CTX_destroy(ctx);
	return 1;
}
#endif /* HAVE_SSL */