1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #ifndef _KERNEL
27 #include <strings.h>
28 #include <limits.h>
29 #include <assert.h>
30 #include <security/cryptoki.h>
31 #endif
32
33 #include <sys/types.h>
34 #include <sys/kmem.h>
35 #include <modes/modes.h>
36 #include <sys/crypto/common.h>
37 #include <sys/crypto/impl.h>
38
39 #if defined(__i386) || defined(__amd64)
40 #include <sys/byteorder.h>
41 #define UNALIGNED_POINTERS_PERMITTED
42 #endif
43
44 /*
45 * Encrypt multiple blocks of data in CCM mode. Decrypt for CCM mode
46 * is done in another function.
47 */
48 int
49 ccm_mode_encrypt_contiguous_blocks(ccm_ctx_t *ctx, char *data, size_t length,
50 crypto_data_t *out, size_t block_size,
51 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
52 void (*copy_block)(uint8_t *, uint8_t *),
53 void (*xor_block)(uint8_t *, uint8_t *))
54 {
55 size_t remainder = length;
56 size_t need;
57 uint8_t *datap = (uint8_t *)data;
58 uint8_t *blockp;
59 uint8_t *lastp;
60 void *iov_or_mp;
61 offset_t offset;
62 uint8_t *out_data_1;
63 uint8_t *out_data_2;
64 size_t out_data_1_len;
65 uint64_t counter;
66 uint8_t *mac_buf;
67
68 if (length + ctx->ccm_remainder_len < block_size) {
69 /* accumulate bytes here and return */
70 bcopy(datap,
71 (uint8_t *)ctx->ccm_remainder + ctx->ccm_remainder_len,
72 length);
73 ctx->ccm_remainder_len += length;
74 ctx->ccm_copy_to = datap;
75 return (CRYPTO_SUCCESS);
76 }
77
78 lastp = (uint8_t *)ctx->ccm_cb;
79 if (out != NULL)
80 crypto_init_ptrs(out, &iov_or_mp, &offset);
81
82 mac_buf = (uint8_t *)ctx->ccm_mac_buf;
83
84 do {
85 /* Unprocessed data from last call. */
86 if (ctx->ccm_remainder_len > 0) {
87 need = block_size - ctx->ccm_remainder_len;
88
89 if (need > remainder)
90 return (CRYPTO_DATA_LEN_RANGE);
91
92 bcopy(datap, &((uint8_t *)ctx->ccm_remainder)
93 [ctx->ccm_remainder_len], need);
94
95 blockp = (uint8_t *)ctx->ccm_remainder;
96 } else {
97 blockp = datap;
98 }
99
100 /*
101 * do CBC MAC
102 *
103 * XOR the previous cipher block current clear block.
104 * mac_buf always contain previous cipher block.
105 */
106 xor_block(blockp, mac_buf);
107 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
108
109 /* ccm_cb is the counter block */
110 encrypt_block(ctx->ccm_keysched, (uint8_t *)ctx->ccm_cb,
111 (uint8_t *)ctx->ccm_tmp);
112
113 lastp = (uint8_t *)ctx->ccm_tmp;
114
115 /*
116 * Increment counter. Counter bits are confined
117 * to the bottom 64 bits of the counter block.
118 */
119 #ifdef _LITTLE_ENDIAN
120 counter = ntohll(ctx->ccm_cb[1] & ctx->ccm_counter_mask);
121 counter = htonll(counter + 1);
122 #else
123 counter = ctx->ccm_cb[1] & ctx->ccm_counter_mask;
124 counter++;
125 #endif /* _LITTLE_ENDIAN */
126 counter &= ctx->ccm_counter_mask;
127 ctx->ccm_cb[1] =
128 (ctx->ccm_cb[1] & ~(ctx->ccm_counter_mask)) | counter;
129
130 /*
131 * XOR encrypted counter block with the current clear block.
132 */
133 xor_block(blockp, lastp);
134
135 ctx->ccm_processed_data_len += block_size;
136
137 if (out == NULL) {
138 if (ctx->ccm_remainder_len > 0) {
139 bcopy(blockp, ctx->ccm_copy_to,
140 ctx->ccm_remainder_len);
141 bcopy(blockp + ctx->ccm_remainder_len, datap,
142 need);
143 }
144 } else {
145 crypto_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
146 &out_data_1_len, &out_data_2, block_size);
147
148 /* copy block to where it belongs */
149 if (out_data_1_len == block_size) {
150 copy_block(lastp, out_data_1);
151 } else {
152 bcopy(lastp, out_data_1, out_data_1_len);
153 if (out_data_2 != NULL) {
154 bcopy(lastp + out_data_1_len,
155 out_data_2,
156 block_size - out_data_1_len);
157 }
158 }
159 /* update offset */
160 out->cd_offset += block_size;
161 }
162
163 /* Update pointer to next block of data to be processed. */
164 if (ctx->ccm_remainder_len != 0) {
165 datap += need;
166 ctx->ccm_remainder_len = 0;
167 } else {
168 datap += block_size;
169 }
170
171 remainder = (size_t)&data[length] - (size_t)datap;
172
173 /* Incomplete last block. */
174 if (remainder > 0 && remainder < block_size) {
175 bcopy(datap, ctx->ccm_remainder, remainder);
176 ctx->ccm_remainder_len = remainder;
177 ctx->ccm_copy_to = datap;
178 goto out;
179 }
180 ctx->ccm_copy_to = NULL;
181
182 } while (remainder > 0);
183
184 out:
185 return (CRYPTO_SUCCESS);
186 }
187
188 void
189 calculate_ccm_mac(ccm_ctx_t *ctx, uint8_t *ccm_mac,
190 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *))
191 {
192 uint64_t counter;
193 uint8_t *counterp, *mac_buf;
194 int i;
195
196 mac_buf = (uint8_t *)ctx->ccm_mac_buf;
197
198 /* first counter block start with index 0 */
199 counter = 0;
200 ctx->ccm_cb[1] = (ctx->ccm_cb[1] & ~(ctx->ccm_counter_mask)) | counter;
201
202 counterp = (uint8_t *)ctx->ccm_tmp;
203 encrypt_block(ctx->ccm_keysched, (uint8_t *)ctx->ccm_cb, counterp);
204
205 /* calculate XOR of MAC with first counter block */
206 for (i = 0; i < ctx->ccm_mac_len; i++) {
207 ccm_mac[i] = mac_buf[i] ^ counterp[i];
208 }
209 }
210
211 /* ARGSUSED */
212 int
213 ccm_encrypt_final(ccm_ctx_t *ctx, crypto_data_t *out, size_t block_size,
214 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
215 void (*xor_block)(uint8_t *, uint8_t *))
216 {
217 uint8_t *lastp, *mac_buf, *ccm_mac_p, *macp;
218 void *iov_or_mp;
219 offset_t offset;
220 uint8_t *out_data_1;
221 uint8_t *out_data_2;
222 size_t out_data_1_len;
223 int i;
224
225 if (out->cd_length < (ctx->ccm_remainder_len + ctx->ccm_mac_len)) {
226 return (CRYPTO_DATA_LEN_RANGE);
227 }
228
229 /*
230 * When we get here, the number of bytes of payload processed
231 * plus whatever data remains, if any,
232 * should be the same as the number of bytes that's being
233 * passed in the argument during init time.
234 */
235 if ((ctx->ccm_processed_data_len + ctx->ccm_remainder_len)
236 != (ctx->ccm_data_len)) {
237 return (CRYPTO_DATA_LEN_RANGE);
238 }
239
240 mac_buf = (uint8_t *)ctx->ccm_mac_buf;
241
242 if (ctx->ccm_remainder_len > 0) {
243
244 /* ccm_mac_input_buf is not used for encryption */
245 macp = (uint8_t *)ctx->ccm_mac_input_buf;
246 bzero(macp, block_size);
247
248 /* copy remainder to temporary buffer */
249 bcopy(ctx->ccm_remainder, macp, ctx->ccm_remainder_len);
250
251 /* calculate the CBC MAC */
252 xor_block(macp, mac_buf);
253 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
254
255 /* calculate the counter mode */
256 lastp = (uint8_t *)ctx->ccm_tmp;
257 encrypt_block(ctx->ccm_keysched, (uint8_t *)ctx->ccm_cb, lastp);
258
259 /* XOR with counter block */
260 for (i = 0; i < ctx->ccm_remainder_len; i++) {
261 macp[i] ^= lastp[i];
262 }
263 ctx->ccm_processed_data_len += ctx->ccm_remainder_len;
264 }
265
266 /* Calculate the CCM MAC */
267 ccm_mac_p = (uint8_t *)ctx->ccm_tmp;
268 calculate_ccm_mac(ctx, ccm_mac_p, encrypt_block);
269
270 crypto_init_ptrs(out, &iov_or_mp, &offset);
271 crypto_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
272 &out_data_1_len, &out_data_2,
273 ctx->ccm_remainder_len + ctx->ccm_mac_len);
274
275 if (ctx->ccm_remainder_len > 0) {
276
277 /* copy temporary block to where it belongs */
278 if (out_data_2 == NULL) {
279 /* everything will fit in out_data_1 */
280 bcopy(macp, out_data_1, ctx->ccm_remainder_len);
281 bcopy(ccm_mac_p, out_data_1 + ctx->ccm_remainder_len,
282 ctx->ccm_mac_len);
283 } else {
284
285 if (out_data_1_len < ctx->ccm_remainder_len) {
286
287 size_t data_2_len_used;
288
289 bcopy(macp, out_data_1, out_data_1_len);
290
291 data_2_len_used = ctx->ccm_remainder_len
292 - out_data_1_len;
293
294 bcopy((uint8_t *)macp + out_data_1_len,
295 out_data_2, data_2_len_used);
296 bcopy(ccm_mac_p, out_data_2 + data_2_len_used,
297 ctx->ccm_mac_len);
298 } else {
299 bcopy(macp, out_data_1, out_data_1_len);
300 if (out_data_1_len == ctx->ccm_remainder_len) {
301 /* mac will be in out_data_2 */
302 bcopy(ccm_mac_p, out_data_2,
303 ctx->ccm_mac_len);
304 } else {
305 size_t len_not_used = out_data_1_len -
306 ctx->ccm_remainder_len;
307 /*
308 * part of mac in will be in
309 * out_data_1, part of the mac will be
310 * in out_data_2
311 */
312 bcopy(ccm_mac_p,
313 out_data_1 + ctx->ccm_remainder_len,
314 len_not_used);
315 bcopy(ccm_mac_p + len_not_used,
316 out_data_2,
317 ctx->ccm_mac_len - len_not_used);
318
319 }
320 }
321 }
322 } else {
323 /* copy block to where it belongs */
324 bcopy(ccm_mac_p, out_data_1, out_data_1_len);
325 if (out_data_2 != NULL) {
326 bcopy(ccm_mac_p + out_data_1_len, out_data_2,
327 block_size - out_data_1_len);
328 }
329 }
330 out->cd_offset += ctx->ccm_remainder_len + ctx->ccm_mac_len;
331 ctx->ccm_remainder_len = 0;
332 return (CRYPTO_SUCCESS);
333 }
334
335 /*
336 * This will only deal with decrypting the last block of the input that
337 * might not be a multiple of block length.
338 */
339 void
340 ccm_decrypt_incomplete_block(ccm_ctx_t *ctx,
341 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *))
342 {
343 uint8_t *datap, *outp, *counterp;
344 int i;
345
346 datap = (uint8_t *)ctx->ccm_remainder;
347 outp = &((ctx->ccm_pt_buf)[ctx->ccm_processed_data_len]);
348
349 counterp = (uint8_t *)ctx->ccm_tmp;
350 encrypt_block(ctx->ccm_keysched, (uint8_t *)ctx->ccm_cb, counterp);
351
352 /* XOR with counter block */
353 for (i = 0; i < ctx->ccm_remainder_len; i++) {
354 outp[i] = datap[i] ^ counterp[i];
355 }
356 }
357
358 /*
359 * This will decrypt the cipher text. However, the plaintext won't be
360 * returned to the caller. It will be returned when decrypt_final() is
361 * called if the MAC matches
362 */
363 /* ARGSUSED */
364 int
365 ccm_mode_decrypt_contiguous_blocks(ccm_ctx_t *ctx, char *data, size_t length,
366 crypto_data_t *out, size_t block_size,
367 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
368 void (*copy_block)(uint8_t *, uint8_t *),
369 void (*xor_block)(uint8_t *, uint8_t *))
370 {
371 size_t remainder = length;
372 size_t need;
373 uint8_t *datap = (uint8_t *)data;
374 uint8_t *blockp;
375 uint8_t *cbp;
376 uint64_t counter;
377 size_t pt_len, total_decrypted_len, mac_len, pm_len, pd_len;
378 uint8_t *resultp;
379 #ifdef _LITTLE_ENDIAN
380 uint8_t *p;
381 #endif /* _LITTLE_ENDIAN */
382
383
384 pm_len = ctx->ccm_processed_mac_len;
385
386 if (pm_len > 0) {
387 uint8_t *tmp;
388 /*
389 * all ciphertext has been processed, just waiting for
390 * part of the value of the mac
391 */
392 if ((pm_len + length) > ctx->ccm_mac_len) {
393 return (CRYPTO_ENCRYPTED_DATA_LEN_RANGE);
394 }
395 tmp = (uint8_t *)ctx->ccm_mac_input_buf;
396
397 bcopy(datap, tmp + pm_len, length);
398
399 ctx->ccm_processed_mac_len += length;
400 return (CRYPTO_SUCCESS);
401 }
402
403 /*
404 * If we decrypt the given data, what total amount of data would
405 * have been decrypted?
406 */
407 pd_len = ctx->ccm_processed_data_len;
408 total_decrypted_len = pd_len + length + ctx->ccm_remainder_len;
409
410 if (total_decrypted_len >
411 (ctx->ccm_data_len + ctx->ccm_mac_len)) {
412 return (CRYPTO_ENCRYPTED_DATA_LEN_RANGE);
413 }
414
415 pt_len = ctx->ccm_data_len;
416
417 if (total_decrypted_len > pt_len) {
418 /*
419 * part of the input will be the MAC, need to isolate that
420 * to be dealt with later. The left-over data in
421 * ccm_remainder_len from last time will not be part of the
422 * MAC. Otherwise, it would have already been taken out
423 * when this call is made last time.
424 */
425 size_t pt_part = pt_len - pd_len - ctx->ccm_remainder_len;
426
427 mac_len = length - pt_part;
428
429 ctx->ccm_processed_mac_len = mac_len;
430 bcopy(data + pt_part, ctx->ccm_mac_input_buf, mac_len);
431
432 if (pt_part + ctx->ccm_remainder_len < block_size) {
433 /*
434 * since this is last of the ciphertext, will
435 * just decrypt with it here
436 */
437 bcopy(datap, &((uint8_t *)ctx->ccm_remainder)
438 [ctx->ccm_remainder_len], pt_part);
439 ctx->ccm_remainder_len += pt_part;
440 ccm_decrypt_incomplete_block(ctx, encrypt_block);
441 ctx->ccm_remainder_len = 0;
442 ctx->ccm_processed_data_len += pt_part;
443 return (CRYPTO_SUCCESS);
444 } else {
445 /* let rest of the code handle this */
446 length = pt_part;
447 }
448 } else if (length + ctx->ccm_remainder_len < block_size) {
449 /* accumulate bytes here and return */
450 bcopy(datap,
451 (uint8_t *)ctx->ccm_remainder + ctx->ccm_remainder_len,
452 length);
453 ctx->ccm_remainder_len += length;
454 ctx->ccm_copy_to = datap;
455 return (CRYPTO_SUCCESS);
456 }
457
458 do {
459 /* Unprocessed data from last call. */
460 if (ctx->ccm_remainder_len > 0) {
461 need = block_size - ctx->ccm_remainder_len;
462
463 if (need > remainder)
464 return (CRYPTO_ENCRYPTED_DATA_LEN_RANGE);
465
466 bcopy(datap, &((uint8_t *)ctx->ccm_remainder)
467 [ctx->ccm_remainder_len], need);
468
469 blockp = (uint8_t *)ctx->ccm_remainder;
470 } else {
471 blockp = datap;
472 }
473
474 /* Calculate the counter mode, ccm_cb is the counter block */
475 cbp = (uint8_t *)ctx->ccm_tmp;
476 encrypt_block(ctx->ccm_keysched, (uint8_t *)ctx->ccm_cb, cbp);
477
478 /*
479 * Increment counter.
480 * Counter bits are confined to the bottom 64 bits
481 */
482 #ifdef _LITTLE_ENDIAN
483 counter = ntohll(ctx->ccm_cb[1] & ctx->ccm_counter_mask);
484 counter = htonll(counter + 1);
485 #else
486 counter = ctx->ccm_cb[1] & ctx->ccm_counter_mask;
487 counter++;
488 #endif /* _LITTLE_ENDIAN */
489 counter &= ctx->ccm_counter_mask;
490 ctx->ccm_cb[1] =
491 (ctx->ccm_cb[1] & ~(ctx->ccm_counter_mask)) | counter;
492
493 /* XOR with the ciphertext */
494 xor_block(blockp, cbp);
495
496 /* Copy the plaintext to the "holding buffer" */
497 resultp = (uint8_t *)ctx->ccm_pt_buf +
498 ctx->ccm_processed_data_len;
499 copy_block(cbp, resultp);
500
501 ctx->ccm_processed_data_len += block_size;
502
503 ctx->ccm_lastp = blockp;
504
505 /* Update pointer to next block of data to be processed. */
506 if (ctx->ccm_remainder_len != 0) {
507 datap += need;
508 ctx->ccm_remainder_len = 0;
509 } else {
510 datap += block_size;
511 }
512
513 remainder = (size_t)&data[length] - (size_t)datap;
514
515 /* Incomplete last block */
516 if (remainder > 0 && remainder < block_size) {
517 bcopy(datap, ctx->ccm_remainder, remainder);
518 ctx->ccm_remainder_len = remainder;
519 ctx->ccm_copy_to = datap;
520 if (ctx->ccm_processed_mac_len > 0) {
521 /*
522 * not expecting anymore ciphertext, just
523 * compute plaintext for the remaining input
524 */
525 ccm_decrypt_incomplete_block(ctx,
526 encrypt_block);
527 ctx->ccm_processed_data_len += remainder;
528 ctx->ccm_remainder_len = 0;
529 }
530 goto out;
531 }
532 ctx->ccm_copy_to = NULL;
533
534 } while (remainder > 0);
535
536 out:
537 return (CRYPTO_SUCCESS);
538 }
539
540 int
541 ccm_decrypt_final(ccm_ctx_t *ctx, crypto_data_t *out, size_t block_size,
542 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
543 void (*copy_block)(uint8_t *, uint8_t *),
544 void (*xor_block)(uint8_t *, uint8_t *))
545 {
546 size_t mac_remain, pt_len;
547 uint8_t *pt, *mac_buf, *macp, *ccm_mac_p;
548 void *iov_or_mp;
549 offset_t offset;
550 uint8_t *out_data_1, *out_data_2;
551 size_t out_data_1_len;
552
553 pt_len = ctx->ccm_data_len;
554
555 /* Make sure output buffer can fit all of the plaintext */
556 if (out->cd_length < pt_len) {
557 return (CRYPTO_DATA_LEN_RANGE);
558 }
559
560 pt = ctx->ccm_pt_buf;
561 mac_remain = ctx->ccm_processed_data_len;
562 mac_buf = (uint8_t *)ctx->ccm_mac_buf;
563
564 macp = (uint8_t *)ctx->ccm_tmp;
565
566 while (mac_remain > 0) {
567
568 if (mac_remain < block_size) {
569 bzero(macp, block_size);
570 bcopy(pt, macp, mac_remain);
571 mac_remain = 0;
572 } else {
573 copy_block(pt, macp);
574 mac_remain -= block_size;
575 pt += block_size;
576 }
577
578 /* calculate the CBC MAC */
579 xor_block(macp, mac_buf);
580 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
581 }
582
583 /* Calculate the CCM MAC */
584 ccm_mac_p = (uint8_t *)ctx->ccm_tmp;
585 calculate_ccm_mac((ccm_ctx_t *)ctx, ccm_mac_p, encrypt_block);
586
587 /* compare the input CCM MAC value with what we calculated */
588 if (bcmp(ctx->ccm_mac_input_buf, ccm_mac_p, ctx->ccm_mac_len)) {
589 /* They don't match */
590 return (CRYPTO_INVALID_MAC);
591 } else {
592 crypto_init_ptrs(out, &iov_or_mp, &offset);
593 crypto_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
594 &out_data_1_len, &out_data_2, pt_len);
595 bcopy(ctx->ccm_pt_buf, out_data_1, out_data_1_len);
596 if (out_data_2 != NULL) {
597 bcopy((ctx->ccm_pt_buf) + out_data_1_len,
598 out_data_2, pt_len - out_data_1_len);
599 }
600 out->cd_offset += pt_len;
601 }
602 return (CRYPTO_SUCCESS);
603 }
604
605 int
606 ccm_validate_args(CK_AES_CCM_PARAMS *ccm_param, boolean_t is_encrypt_init)
607 {
608 size_t macSize, nonceSize;
609 uint8_t q;
610 uint64_t maxValue;
611
612 /*
613 * Check the length of the MAC. The only valid
614 * lengths for the MAC are: 4, 6, 8, 10, 12, 14, 16
615 */
616 macSize = ccm_param->ulMACSize;
617 if ((macSize < 4) || (macSize > 16) || ((macSize % 2) != 0)) {
618 return (CRYPTO_MECHANISM_PARAM_INVALID);
619 }
620
621 /* Check the nonce length. Valid values are 7, 8, 9, 10, 11, 12, 13 */
622 nonceSize = ccm_param->ulNonceSize;
623 if ((nonceSize < 7) || (nonceSize > 13)) {
624 return (CRYPTO_MECHANISM_PARAM_INVALID);
625 }
626
627 /* q is the length of the field storing the length, in bytes */
628 q = (uint8_t)((15 - nonceSize) & 0xFF);
629
630
631 /*
632 * If it is decrypt, need to make sure size of ciphertext is at least
633 * bigger than MAC len
634 */
635 if ((!is_encrypt_init) && (ccm_param->ulDataSize < macSize)) {
636 return (CRYPTO_MECHANISM_PARAM_INVALID);
637 }
638
639 /*
640 * Check to make sure the length of the payload is within the
641 * range of values allowed by q
642 */
643 if (q < 8) {
644 maxValue = (1ULL << (q * 8)) - 1;
645 } else {
646 maxValue = ULONG_MAX;
647 }
648
649 if (ccm_param->ulDataSize > maxValue) {
650 return (CRYPTO_MECHANISM_PARAM_INVALID);
651 }
652 return (CRYPTO_SUCCESS);
653 }
654
655 /*
656 * Format the first block used in CBC-MAC (B0) and the initial counter
657 * block based on formatting functions and counter generation functions
658 * specified in RFC 3610 and NIST publication 800-38C, appendix A
659 *
660 * b0 is the first block used in CBC-MAC
661 * cb0 is the first counter block
662 *
663 * It's assumed that the arguments b0 and cb0 are preallocated AES blocks
664 *
665 */
666 static void
667 ccm_format_initial_blocks(uchar_t *nonce, ulong_t nonceSize,
668 ulong_t authDataSize, uint8_t *b0, ccm_ctx_t *aes_ctx)
669 {
670 uint64_t payloadSize;
671 uint8_t t, q, have_adata = 0;
672 size_t limit;
673 int i, j, k;
674 uint64_t mask = 0;
675 uint8_t *cb;
676
677 q = (uint8_t)((15 - nonceSize) & 0xFF);
678 t = (uint8_t)((aes_ctx->ccm_mac_len) & 0xFF);
679
680 /* Construct the first octet of b0 */
681 if (authDataSize > 0) {
682 have_adata = 1;
683 }
684 b0[0] = (have_adata << 6) | (((t - 2) / 2) << 3) | (q - 1);
685
686 /* copy the nonce value into b0 */
687 bcopy(nonce, &(b0[1]), nonceSize);
688
689 /* store the length of the payload into b0 */
690 bzero(&(b0[1+nonceSize]), q);
691
692 payloadSize = aes_ctx->ccm_data_len;
693 limit = 8 < q ? 8 : q;
694
695 for (i = 0, j = 0, k = 15; i < limit; i++, j += 8, k--) {
696 b0[k] = (uint8_t)((payloadSize >> j) & 0xFF);
697 }
698
699 /* format the counter block */
700
701 cb = (uint8_t *)aes_ctx->ccm_cb;
702
703 cb[0] = 0x07 & (q-1); /* first byte */
704
705 /* copy the nonce value into the counter block */
706 bcopy(nonce, &(cb[1]), nonceSize);
707
708 bzero(&(cb[1+nonceSize]), q);
709
710 /* Create the mask for the counter field based on the size of nonce */
711 q <<= 3;
712 while (q-- > 0) {
713 mask |= (1ULL << q);
714 }
715
716 #ifdef _LITTLE_ENDIAN
717 mask = htonll(mask);
718 #endif
719 aes_ctx->ccm_counter_mask = mask;
720
721 /*
722 * During calculation, we start using counter block 1, we will
723 * set it up right here.
724 * We can just set the last byte to have the value 1, because
725 * even with the biggest nonce of 13, the last byte of the
726 * counter block will be used for the counter value.
727 */
728 cb[15] = 0x01;
729 }
730
731 /*
732 * Encode the length of the associated data as
733 * specified in RFC 3610 and NIST publication 800-38C, appendix A
734 */
735 static void
736 encode_adata_len(ulong_t auth_data_len, uint8_t *encoded, size_t *encoded_len)
737 {
738 #ifdef UNALIGNED_POINTERS_PERMITTED
739 uint32_t *lencoded_ptr;
740 #ifdef _LP64
741 uint64_t *llencoded_ptr;
742 #endif
743 #endif /* UNALIGNED_POINTERS_PERMITTED */
744
745 if (auth_data_len < ((1ULL<<16) - (1ULL<<8))) {
746 /* 0 < a < (2^16-2^8) */
747 *encoded_len = 2;
748 encoded[0] = (auth_data_len & 0xff00) >> 8;
749 encoded[1] = auth_data_len & 0xff;
750
751 } else if ((auth_data_len >= ((1ULL<<16) - (1ULL<<8))) &&
752 (auth_data_len < (1ULL << 31))) {
753 /* (2^16-2^8) <= a < 2^32 */
754 *encoded_len = 6;
755 encoded[0] = 0xff;
756 encoded[1] = 0xfe;
757 #ifdef UNALIGNED_POINTERS_PERMITTED
758 lencoded_ptr = (uint32_t *)&encoded[2];
759 *lencoded_ptr = htonl(auth_data_len);
760 #else
761 encoded[2] = (auth_data_len & 0xff000000) >> 24;
762 encoded[3] = (auth_data_len & 0xff0000) >> 16;
763 encoded[4] = (auth_data_len & 0xff00) >> 8;
764 encoded[5] = auth_data_len & 0xff;
765 #endif /* UNALIGNED_POINTERS_PERMITTED */
766
767 #ifdef _LP64
768 } else {
769 /* 2^32 <= a < 2^64 */
770 *encoded_len = 10;
771 encoded[0] = 0xff;
772 encoded[1] = 0xff;
773 #ifdef UNALIGNED_POINTERS_PERMITTED
774 llencoded_ptr = (uint64_t *)&encoded[2];
775 *llencoded_ptr = htonl(auth_data_len);
776 #else
777 encoded[2] = (auth_data_len & 0xff00000000000000) >> 56;
778 encoded[3] = (auth_data_len & 0xff000000000000) >> 48;
779 encoded[4] = (auth_data_len & 0xff0000000000) >> 40;
780 encoded[5] = (auth_data_len & 0xff00000000) >> 32;
781 encoded[6] = (auth_data_len & 0xff000000) >> 24;
782 encoded[7] = (auth_data_len & 0xff0000) >> 16;
783 encoded[8] = (auth_data_len & 0xff00) >> 8;
784 encoded[9] = auth_data_len & 0xff;
785 #endif /* UNALIGNED_POINTERS_PERMITTED */
786 #endif /* _LP64 */
787 }
788 }
789
790 /*
791 * The following function should be call at encrypt or decrypt init time
792 * for AES CCM mode.
793 */
794 int
795 ccm_init(ccm_ctx_t *ctx, unsigned char *nonce, size_t nonce_len,
796 unsigned char *auth_data, size_t auth_data_len, size_t block_size,
797 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
798 void (*xor_block)(uint8_t *, uint8_t *))
799 {
800 uint8_t *mac_buf, *datap, *ivp, *authp;
801 size_t remainder, processed;
802 uint8_t encoded_a[10]; /* max encoded auth data length is 10 octets */
803 size_t encoded_a_len = 0;
804
805 mac_buf = (uint8_t *)&(ctx->ccm_mac_buf);
806
807 /*
808 * Format the 1st block for CBC-MAC and construct the
809 * 1st counter block.
810 *
811 * aes_ctx->ccm_iv is used for storing the counter block
812 * mac_buf will store b0 at this time.
813 */
814 ccm_format_initial_blocks(nonce, nonce_len,
815 auth_data_len, mac_buf, ctx);
816
817 /* The IV for CBC MAC for AES CCM mode is always zero */
818 ivp = (uint8_t *)ctx->ccm_tmp;
819 bzero(ivp, block_size);
820
821 xor_block(ivp, mac_buf);
822
823 /* encrypt the nonce */
824 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
825
826 /* take care of the associated data, if any */
827 if (auth_data_len == 0) {
828 return (CRYPTO_SUCCESS);
829 }
830
831 encode_adata_len(auth_data_len, encoded_a, &encoded_a_len);
832
833 remainder = auth_data_len;
834
835 /* 1st block: it contains encoded associated data, and some data */
836 authp = (uint8_t *)ctx->ccm_tmp;
837 bzero(authp, block_size);
838 bcopy(encoded_a, authp, encoded_a_len);
839 processed = block_size - encoded_a_len;
840 if (processed > auth_data_len) {
841 /* in case auth_data is very small */
842 processed = auth_data_len;
843 }
844 bcopy(auth_data, authp+encoded_a_len, processed);
845 /* xor with previous buffer */
846 xor_block(authp, mac_buf);
847 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
848 remainder -= processed;
849 if (remainder == 0) {
850 /* a small amount of associated data, it's all done now */
851 return (CRYPTO_SUCCESS);
852 }
853
854 do {
855 if (remainder < block_size) {
856 /*
857 * There's not a block full of data, pad rest of
858 * buffer with zero
859 */
860 bzero(authp, block_size);
861 bcopy(&(auth_data[processed]), authp, remainder);
862 datap = (uint8_t *)authp;
863 remainder = 0;
864 } else {
865 datap = (uint8_t *)(&(auth_data[processed]));
866 processed += block_size;
867 remainder -= block_size;
868 }
869
870 xor_block(datap, mac_buf);
871 encrypt_block(ctx->ccm_keysched, mac_buf, mac_buf);
872
873 } while (remainder > 0);
874
875 return (CRYPTO_SUCCESS);
876 }
877
878 int
879 ccm_init_ctx(ccm_ctx_t *ccm_ctx, char *param, int kmflag,
880 boolean_t is_encrypt_init, size_t block_size,
881 int (*encrypt_block)(const void *, const uint8_t *, uint8_t *),
882 void (*xor_block)(uint8_t *, uint8_t *))
883 {
884 int rv;
885 CK_AES_CCM_PARAMS *ccm_param;
886
887 if (param != NULL) {
888 ccm_param = (CK_AES_CCM_PARAMS *)param;
889
890 if ((rv = ccm_validate_args(ccm_param,
891 is_encrypt_init)) != 0) {
892 return (rv);
893 }
894
895 ccm_ctx->ccm_mac_len = ccm_param->ulMACSize;
896 if (is_encrypt_init) {
897 ccm_ctx->ccm_data_len = ccm_param->ulDataSize;
898 } else {
899 ccm_ctx->ccm_data_len =
900 ccm_param->ulDataSize - ccm_ctx->ccm_mac_len;
901 ccm_ctx->ccm_processed_mac_len = 0;
902 }
903 ccm_ctx->ccm_processed_data_len = 0;
904
905 ccm_ctx->ccm_flags |= CCM_MODE;
906 } else {
907 rv = CRYPTO_MECHANISM_PARAM_INVALID;
908 goto out;
909 }
910
911 if (ccm_init(ccm_ctx, ccm_param->nonce, ccm_param->ulNonceSize,
912 ccm_param->authData, ccm_param->ulAuthDataSize, block_size,
913 encrypt_block, xor_block) != 0) {
914 rv = CRYPTO_MECHANISM_PARAM_INVALID;
915 goto out;
916 }
917 if (!is_encrypt_init) {
918 /* allocate buffer for storing decrypted plaintext */
919 #ifdef _KERNEL
920 ccm_ctx->ccm_pt_buf = kmem_alloc(ccm_ctx->ccm_data_len,
921 kmflag);
922 #else
923 ccm_ctx->ccm_pt_buf = malloc(ccm_ctx->ccm_data_len);
924 #endif
925 if (ccm_ctx->ccm_pt_buf == NULL) {
926 rv = CRYPTO_HOST_MEMORY;
927 }
928 }
929 out:
930 return (rv);
931 }
932
933 void *
934 ccm_alloc_ctx(int kmflag)
935 {
936 ccm_ctx_t *ccm_ctx;
937
938 #ifdef _KERNEL
939 if ((ccm_ctx = kmem_zalloc(sizeof (ccm_ctx_t), kmflag)) == NULL)
940 #else
941 if ((ccm_ctx = calloc(1, sizeof (ccm_ctx_t))) == NULL)
942 #endif
943 return (NULL);
944
945 ccm_ctx->ccm_flags = CCM_MODE;
946 return (ccm_ctx);
947 }