2 * AES CCM routines supporting the Power 7+ Nest Accelerators driver
4 * Copyright (C) 2012 International Business Machines Inc.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 only.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 * Author: Kent Yoder <yoder1@us.ibm.com>
22 #include <crypto/internal/aead.h>
23 #include <crypto/aes.h>
24 #include <crypto/algapi.h>
25 #include <crypto/scatterwalk.h>
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/crypto.h>
31 #include "nx_csbcpb.h"
35 static int ccm_aes_nx_set_key(struct crypto_aead *tfm,
39 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
40 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
41 struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;
43 nx_ctx_init(nx_ctx, HCOP_FC_AES);
47 NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
48 NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128);
49 nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
55 csbcpb->cpb.hdr.mode = NX_MODE_AES_CCM;
56 memcpy(csbcpb->cpb.aes_ccm.key, in_key, key_len);
58 csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_CCA;
59 memcpy(csbcpb_aead->cpb.aes_cca.key, in_key, key_len);
65 static int ccm4309_aes_nx_set_key(struct crypto_aead *tfm,
69 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base);
76 memcpy(nx_ctx->priv.ccm.nonce, in_key + key_len, 3);
78 return ccm_aes_nx_set_key(tfm, in_key, key_len);
81 static int ccm_aes_nx_setauthsize(struct crypto_aead *tfm,
82 unsigned int authsize)
97 crypto_aead_crt(tfm)->authsize = authsize;
102 static int ccm4309_aes_nx_setauthsize(struct crypto_aead *tfm,
103 unsigned int authsize)
114 crypto_aead_crt(tfm)->authsize = authsize;
119 /* taken from crypto/ccm.c */
120 static int set_msg_len(u8 *block, unsigned int msglen, int csize)
124 memset(block, 0, csize);
129 else if (msglen > (unsigned int)(1 << (8 * csize)))
132 data = cpu_to_be32(msglen);
133 memcpy(block - csize, (u8 *)&data + 4 - csize, csize);
138 /* taken from crypto/ccm.c */
139 static inline int crypto_ccm_check_iv(const u8 *iv)
141 /* 2 <= L <= 8, so 1 <= L' <= 7. */
142 if (1 > iv[0] || iv[0] > 7)
148 /* based on code from crypto/ccm.c */
149 static int generate_b0(u8 *iv, unsigned int assoclen, unsigned int authsize,
150 unsigned int cryptlen, u8 *b0)
152 unsigned int l, lp, m = authsize;
160 /* set m, bits 3-5 */
161 *b0 |= (8 * ((m - 2) / 2));
163 /* set adata, bit 6, if associated data is used */
167 rc = set_msg_len(b0 + 16 - l, cryptlen, l);
172 static int generate_pat(u8 *iv,
173 struct aead_request *req,
174 struct nx_crypto_ctx *nx_ctx,
175 unsigned int authsize,
179 struct nx_sg *nx_insg = nx_ctx->in_sg;
180 struct nx_sg *nx_outsg = nx_ctx->out_sg;
181 unsigned int iauth_len = 0;
182 u8 tmp[16], *b1 = NULL, *b0 = NULL, *result = NULL;
185 /* zero the ctr value */
186 memset(iv + 15 - iv[0], 0, iv[0] + 1);
188 /* page 78 of nx_wb.pdf has,
189 * Note: RFC3610 allows the AAD data to be up to 2^64 -1 bytes
190 * in length. If a full message is used, the AES CCA implementation
191 * restricts the maximum AAD length to 2^32 -1 bytes.
192 * If partial messages are used, the implementation supports
193 * 2^64 -1 bytes maximum AAD length.
195 * However, in the cryptoapi's aead_request structure,
196 * assoclen is an unsigned int, thus it cannot hold a length
197 * value greater than 2^32 - 1.
198 * Thus the AAD is further constrained by this and is never
202 if (!req->assoclen) {
203 b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
204 } else if (req->assoclen <= 14) {
205 /* if associated data is 14 bytes or less, we do 1 GCM
206 * operation on 2 AES blocks, B0 (stored in the csbcpb) and B1,
207 * which is fed in through the source buffers here */
208 b0 = nx_ctx->csbcpb->cpb.aes_ccm.in_pat_or_b0;
209 b1 = nx_ctx->priv.ccm.iauth_tag;
210 iauth_len = req->assoclen;
211 } else if (req->assoclen <= 65280) {
212 /* if associated data is less than (2^16 - 2^8), we construct
213 * B1 differently and feed in the associated data to a CCA
215 b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
216 b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
219 b0 = nx_ctx->csbcpb_aead->cpb.aes_cca.b0;
220 b1 = nx_ctx->csbcpb_aead->cpb.aes_cca.b1;
225 rc = generate_b0(iv, req->assoclen, authsize, nbytes, b0);
230 * add control info for associated data
231 * RFC 3610 and NIST Special Publication 800-38C
235 if (req->assoclen <= 65280) {
236 *(u16 *)b1 = (u16)req->assoclen;
237 scatterwalk_map_and_copy(b1 + 2, req->assoc, 0,
238 iauth_len, SCATTERWALK_FROM_SG);
240 *(u16 *)b1 = (u16)(0xfffe);
241 *(u32 *)&b1[2] = (u32)req->assoclen;
242 scatterwalk_map_and_copy(b1 + 6, req->assoc, 0,
243 iauth_len, SCATTERWALK_FROM_SG);
247 /* now copy any remaining AAD to scatterlist and call nx... */
248 if (!req->assoclen) {
250 } else if (req->assoclen <= 14) {
251 nx_insg = nx_build_sg_list(nx_insg, b1, 16, nx_ctx->ap->sglen);
252 nx_outsg = nx_build_sg_list(nx_outsg, tmp, 16,
255 /* inlen should be negative, indicating to phyp that its a
256 * pointer to an sg list */
257 nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) *
258 sizeof(struct nx_sg);
259 nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) *
260 sizeof(struct nx_sg);
262 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_ENDE_ENCRYPT;
263 NX_CPB_FDM(nx_ctx->csbcpb) |= NX_FDM_INTERMEDIATE;
265 result = nx_ctx->csbcpb->cpb.aes_ccm.out_pat_or_mac;
267 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
268 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
272 atomic_inc(&(nx_ctx->stats->aes_ops));
273 atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));
277 unsigned int processed = 0, to_process;
279 /* page_limit: number of sg entries that fit on one page */
280 max_sg_len = min_t(u32,
281 nx_driver.of.max_sg_len/sizeof(struct nx_sg),
284 processed += iauth_len;
287 to_process = min_t(u32, req->assoclen - processed,
288 nx_ctx->ap->databytelen);
289 to_process = min_t(u64, to_process,
290 NX_PAGE_SIZE * (max_sg_len - 1));
292 if ((to_process + processed) < req->assoclen) {
293 NX_CPB_FDM(nx_ctx->csbcpb_aead) |=
296 NX_CPB_FDM(nx_ctx->csbcpb_aead) &=
297 ~NX_FDM_INTERMEDIATE;
300 nx_insg = nx_walk_and_build(nx_ctx->in_sg,
302 req->assoc, processed,
305 nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_insg) *
306 sizeof(struct nx_sg);
308 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
310 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
311 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
315 memcpy(nx_ctx->csbcpb_aead->cpb.aes_cca.b0,
316 nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0,
319 NX_CPB_FDM(nx_ctx->csbcpb_aead) |= NX_FDM_CONTINUATION;
321 atomic_inc(&(nx_ctx->stats->aes_ops));
322 atomic64_add(req->assoclen,
323 &(nx_ctx->stats->aes_bytes));
325 processed += to_process;
326 } while (processed < req->assoclen);
328 result = nx_ctx->csbcpb_aead->cpb.aes_cca.out_pat_or_b0;
331 memcpy(out, result, AES_BLOCK_SIZE);
336 static int ccm_nx_decrypt(struct aead_request *req,
337 struct blkcipher_desc *desc)
339 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
340 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
341 unsigned int nbytes = req->cryptlen;
342 unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
343 struct nx_ccm_priv *priv = &nx_ctx->priv.ccm;
344 unsigned long irq_flags;
345 unsigned int processed = 0, to_process;
349 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
353 /* copy out the auth tag to compare with later */
354 scatterwalk_map_and_copy(priv->oauth_tag,
355 req->src, nbytes, authsize,
356 SCATTERWALK_FROM_SG);
358 rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
359 csbcpb->cpb.aes_ccm.in_pat_or_b0);
363 /* page_limit: number of sg entries that fit on one page */
364 max_sg_len = min_t(u32, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
369 /* to_process: the AES_BLOCK_SIZE data chunk to process in this
370 * update. This value is bound by sg list limits.
372 to_process = min_t(u64, nbytes - processed,
373 nx_ctx->ap->databytelen);
374 to_process = min_t(u64, to_process,
375 NX_PAGE_SIZE * (max_sg_len - 1));
377 if ((to_process + processed) < nbytes)
378 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
380 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
382 NX_CPB_FDM(nx_ctx->csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
384 rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src,
385 to_process, processed,
386 csbcpb->cpb.aes_ccm.iv_or_ctr);
390 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
391 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
395 /* for partial completion, copy following for next
398 memcpy(desc->info, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
399 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
400 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
401 memcpy(csbcpb->cpb.aes_ccm.in_s0,
402 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
404 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
407 atomic_inc(&(nx_ctx->stats->aes_ops));
408 atomic64_add(csbcpb->csb.processed_byte_count,
409 &(nx_ctx->stats->aes_bytes));
411 processed += to_process;
412 } while (processed < nbytes);
414 rc = memcmp(csbcpb->cpb.aes_ccm.out_pat_or_mac, priv->oauth_tag,
415 authsize) ? -EBADMSG : 0;
417 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
421 static int ccm_nx_encrypt(struct aead_request *req,
422 struct blkcipher_desc *desc)
424 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
425 struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
426 unsigned int nbytes = req->cryptlen;
427 unsigned int authsize = crypto_aead_authsize(crypto_aead_reqtfm(req));
428 unsigned long irq_flags;
429 unsigned int processed = 0, to_process;
433 spin_lock_irqsave(&nx_ctx->lock, irq_flags);
435 rc = generate_pat(desc->info, req, nx_ctx, authsize, nbytes,
436 csbcpb->cpb.aes_ccm.in_pat_or_b0);
440 /* page_limit: number of sg entries that fit on one page */
441 max_sg_len = min_t(u32, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
445 /* to process: the AES_BLOCK_SIZE data chunk to process in this
446 * update. This value is bound by sg list limits.
448 to_process = min_t(u64, nbytes - processed,
449 nx_ctx->ap->databytelen);
450 to_process = min_t(u64, to_process,
451 NX_PAGE_SIZE * (max_sg_len - 1));
453 if ((to_process + processed) < nbytes)
454 NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
456 NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
458 NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
460 rc = nx_build_sg_lists(nx_ctx, desc, req->dst, req->src,
461 to_process, processed,
462 csbcpb->cpb.aes_ccm.iv_or_ctr);
466 rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
467 req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
471 /* for partial completion, copy following for next
474 memcpy(desc->info, csbcpb->cpb.aes_ccm.out_ctr, AES_BLOCK_SIZE);
475 memcpy(csbcpb->cpb.aes_ccm.in_pat_or_b0,
476 csbcpb->cpb.aes_ccm.out_pat_or_mac, AES_BLOCK_SIZE);
477 memcpy(csbcpb->cpb.aes_ccm.in_s0,
478 csbcpb->cpb.aes_ccm.out_s0, AES_BLOCK_SIZE);
480 NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
483 atomic_inc(&(nx_ctx->stats->aes_ops));
484 atomic64_add(csbcpb->csb.processed_byte_count,
485 &(nx_ctx->stats->aes_bytes));
487 processed += to_process;
489 } while (processed < nbytes);
491 /* copy out the auth tag */
492 scatterwalk_map_and_copy(csbcpb->cpb.aes_ccm.out_pat_or_mac,
493 req->dst, nbytes, authsize,
497 spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
501 static int ccm4309_aes_nx_encrypt(struct aead_request *req)
503 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
504 struct blkcipher_desc desc;
505 u8 *iv = nx_ctx->priv.ccm.iv;
508 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
509 memcpy(iv + 4, req->iv, 8);
512 desc.tfm = (struct crypto_blkcipher *)req->base.tfm;
514 return ccm_nx_encrypt(req, &desc);
517 static int ccm_aes_nx_encrypt(struct aead_request *req)
519 struct blkcipher_desc desc;
523 desc.tfm = (struct crypto_blkcipher *)req->base.tfm;
525 rc = crypto_ccm_check_iv(desc.info);
529 return ccm_nx_encrypt(req, &desc);
532 static int ccm4309_aes_nx_decrypt(struct aead_request *req)
534 struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
535 struct blkcipher_desc desc;
536 u8 *iv = nx_ctx->priv.ccm.iv;
539 memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
540 memcpy(iv + 4, req->iv, 8);
543 desc.tfm = (struct crypto_blkcipher *)req->base.tfm;
545 return ccm_nx_decrypt(req, &desc);
548 static int ccm_aes_nx_decrypt(struct aead_request *req)
550 struct blkcipher_desc desc;
554 desc.tfm = (struct crypto_blkcipher *)req->base.tfm;
556 rc = crypto_ccm_check_iv(desc.info);
560 return ccm_nx_decrypt(req, &desc);
563 /* tell the block cipher walk routines that this is a stream cipher by
564 * setting cra_blocksize to 1. Even using blkcipher_walk_virt_block
565 * during encrypt/decrypt doesn't solve this problem, because it calls
566 * blkcipher_walk_done under the covers, which doesn't use walk->blocksize,
567 * but instead uses this tfm->blocksize. */
568 struct crypto_alg nx_ccm_aes_alg = {
569 .cra_name = "ccm(aes)",
570 .cra_driver_name = "ccm-aes-nx",
572 .cra_flags = CRYPTO_ALG_TYPE_AEAD |
573 CRYPTO_ALG_NEED_FALLBACK,
575 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
576 .cra_type = &crypto_aead_type,
577 .cra_module = THIS_MODULE,
578 .cra_init = nx_crypto_ctx_aes_ccm_init,
579 .cra_exit = nx_crypto_ctx_exit,
581 .ivsize = AES_BLOCK_SIZE,
582 .maxauthsize = AES_BLOCK_SIZE,
583 .setkey = ccm_aes_nx_set_key,
584 .setauthsize = ccm_aes_nx_setauthsize,
585 .encrypt = ccm_aes_nx_encrypt,
586 .decrypt = ccm_aes_nx_decrypt,
590 struct crypto_alg nx_ccm4309_aes_alg = {
591 .cra_name = "rfc4309(ccm(aes))",
592 .cra_driver_name = "rfc4309-ccm-aes-nx",
594 .cra_flags = CRYPTO_ALG_TYPE_AEAD |
595 CRYPTO_ALG_NEED_FALLBACK,
597 .cra_ctxsize = sizeof(struct nx_crypto_ctx),
598 .cra_type = &crypto_nivaead_type,
599 .cra_module = THIS_MODULE,
600 .cra_init = nx_crypto_ctx_aes_ccm_init,
601 .cra_exit = nx_crypto_ctx_exit,
604 .maxauthsize = AES_BLOCK_SIZE,
605 .setkey = ccm4309_aes_nx_set_key,
606 .setauthsize = ccm4309_aes_nx_setauthsize,
607 .encrypt = ccm4309_aes_nx_encrypt,
608 .decrypt = ccm4309_aes_nx_decrypt,