| /** |
| * AES GCM routines supporting the Power 7+ Nest Accelerators driver |
| * |
| * Copyright (C) 2012 International Business Machines Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; version 2 only. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| * Author: Kent Yoder <yoder1@us.ibm.com> |
| */ |
| |
| #include <crypto/internal/aead.h> |
| #include <crypto/aes.h> |
| #include <crypto/algapi.h> |
| #include <crypto/scatterwalk.h> |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/crypto.h> |
| #include <asm/vio.h> |
| |
| #include "nx_csbcpb.h" |
| #include "nx.h" |
| |
| |
| static int gcm_aes_nx_set_key(struct crypto_aead *tfm, |
| const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base); |
| struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; |
| struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; |
| |
| nx_ctx_init(nx_ctx, HCOP_FC_AES); |
| |
| switch (key_len) { |
| case AES_KEYSIZE_128: |
| NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128); |
| NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_128); |
| nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128]; |
| break; |
| case AES_KEYSIZE_192: |
| NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192); |
| NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_192); |
| nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192]; |
| break; |
| case AES_KEYSIZE_256: |
| NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256); |
| NX_CPB_SET_KEY_SIZE(csbcpb_aead, NX_KS_AES_256); |
| nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256]; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; |
| memcpy(csbcpb->cpb.aes_gcm.key, in_key, key_len); |
| |
| csbcpb_aead->cpb.hdr.mode = NX_MODE_AES_GCA; |
| memcpy(csbcpb_aead->cpb.aes_gca.key, in_key, key_len); |
| |
| return 0; |
| } |
| |
| static int gcm4106_aes_nx_set_key(struct crypto_aead *tfm, |
| const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&tfm->base); |
| char *nonce = nx_ctx->priv.gcm.nonce; |
| int rc; |
| |
| if (key_len < 4) |
| return -EINVAL; |
| |
| key_len -= 4; |
| |
| rc = gcm_aes_nx_set_key(tfm, in_key, key_len); |
| if (rc) |
| goto out; |
| |
| memcpy(nonce, in_key + key_len, 4); |
| out: |
| return rc; |
| } |
| |
| static int gcm_aes_nx_setauthsize(struct crypto_aead *tfm, |
| unsigned int authsize) |
| { |
| if (authsize > crypto_aead_alg(tfm)->maxauthsize) |
| return -EINVAL; |
| |
| crypto_aead_crt(tfm)->authsize = authsize; |
| |
| return 0; |
| } |
| |
| static int gcm4106_aes_nx_setauthsize(struct crypto_aead *tfm, |
| unsigned int authsize) |
| { |
| switch (authsize) { |
| case 8: |
| case 12: |
| case 16: |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| crypto_aead_crt(tfm)->authsize = authsize; |
| |
| return 0; |
| } |
| |
| static int nx_gca(struct nx_crypto_ctx *nx_ctx, |
| struct aead_request *req, |
| u8 *out) |
| { |
| struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; |
| int rc = -EINVAL; |
| struct scatter_walk walk; |
| struct nx_sg *nx_sg = nx_ctx->in_sg; |
| |
| if (req->assoclen > nx_ctx->ap->databytelen) |
| goto out; |
| |
| if (req->assoclen <= AES_BLOCK_SIZE) { |
| scatterwalk_start(&walk, req->assoc); |
| scatterwalk_copychunks(out, &walk, req->assoclen, |
| SCATTERWALK_FROM_SG); |
| scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0); |
| |
| rc = 0; |
| goto out; |
| } |
| |
| nx_sg = nx_walk_and_build(nx_sg, nx_ctx->ap->sglen, req->assoc, 0, |
| req->assoclen); |
| nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_sg) * sizeof(struct nx_sg); |
| |
| rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead, |
| req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); |
| if (rc) |
| goto out; |
| |
| atomic_inc(&(nx_ctx->stats->aes_ops)); |
| atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes)); |
| |
| memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE); |
| out: |
| return rc; |
| } |
| |
| static int gcm_aes_nx_crypt(struct aead_request *req, int enc) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm); |
| struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; |
| struct blkcipher_desc desc; |
| unsigned int nbytes = req->cryptlen; |
| int rc = -EINVAL; |
| |
| if (nbytes > nx_ctx->ap->databytelen) |
| goto out; |
| |
| desc.info = nx_ctx->priv.gcm.iv; |
| /* initialize the counter */ |
| *(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1; |
| |
| /* For scenarios where the input message is zero length, AES CTR mode |
| * may be used. Set the source data to be a single block (16B) of all |
| * zeros, and set the input IV value to be the same as the GMAC IV |
| * value. - nx_wb 4.8.1.3 */ |
| if (nbytes == 0) { |
| char src[AES_BLOCK_SIZE] = {}; |
| struct scatterlist sg; |
| |
| desc.tfm = crypto_alloc_blkcipher("ctr(aes)", 0, 0); |
| if (IS_ERR(desc.tfm)) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| crypto_blkcipher_setkey(desc.tfm, csbcpb->cpb.aes_gcm.key, |
| NX_CPB_KEY_SIZE(csbcpb) == NX_KS_AES_128 ? 16 : |
| NX_CPB_KEY_SIZE(csbcpb) == NX_KS_AES_192 ? 24 : 32); |
| |
| sg_init_one(&sg, src, AES_BLOCK_SIZE); |
| if (enc) |
| crypto_blkcipher_encrypt_iv(&desc, req->dst, &sg, |
| AES_BLOCK_SIZE); |
| else |
| crypto_blkcipher_decrypt_iv(&desc, req->dst, &sg, |
| AES_BLOCK_SIZE); |
| crypto_free_blkcipher(desc.tfm); |
| |
| rc = 0; |
| goto out; |
| } |
| |
| desc.tfm = (struct crypto_blkcipher *)req->base.tfm; |
| |
| csbcpb->cpb.aes_gcm.bit_length_aad = req->assoclen * 8; |
| |
| if (req->assoclen) { |
| rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad); |
| if (rc) |
| goto out; |
| } |
| |
| if (enc) |
| NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; |
| else |
| nbytes -= AES_BLOCK_SIZE; |
| |
| csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8; |
| |
| rc = nx_build_sg_lists(nx_ctx, &desc, req->dst, req->src, nbytes, |
| csbcpb->cpb.aes_gcm.iv_or_cnt); |
| if (rc) |
| goto out; |
| |
| rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, |
| req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); |
| if (rc) |
| goto out; |
| |
| atomic_inc(&(nx_ctx->stats->aes_ops)); |
| atomic64_add(csbcpb->csb.processed_byte_count, |
| &(nx_ctx->stats->aes_bytes)); |
| |
| if (enc) { |
| /* copy out the auth tag */ |
| scatterwalk_map_and_copy(csbcpb->cpb.aes_gcm.out_pat_or_mac, |
| req->dst, nbytes, |
| crypto_aead_authsize(crypto_aead_reqtfm(req)), |
| SCATTERWALK_TO_SG); |
| } else if (req->assoclen) { |
| u8 *itag = nx_ctx->priv.gcm.iauth_tag; |
| u8 *otag = csbcpb->cpb.aes_gcm.out_pat_or_mac; |
| |
| scatterwalk_map_and_copy(itag, req->dst, nbytes, |
| crypto_aead_authsize(crypto_aead_reqtfm(req)), |
| SCATTERWALK_FROM_SG); |
| rc = memcmp(itag, otag, |
| crypto_aead_authsize(crypto_aead_reqtfm(req))) ? |
| -EBADMSG : 0; |
| } |
| out: |
| return rc; |
| } |
| |
| static int gcm_aes_nx_encrypt(struct aead_request *req) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm); |
| char *iv = nx_ctx->priv.gcm.iv; |
| |
| memcpy(iv, req->iv, 12); |
| |
| return gcm_aes_nx_crypt(req, 1); |
| } |
| |
| static int gcm_aes_nx_decrypt(struct aead_request *req) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm); |
| char *iv = nx_ctx->priv.gcm.iv; |
| |
| memcpy(iv, req->iv, 12); |
| |
| return gcm_aes_nx_crypt(req, 0); |
| } |
| |
| static int gcm4106_aes_nx_encrypt(struct aead_request *req) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm); |
| char *iv = nx_ctx->priv.gcm.iv; |
| char *nonce = nx_ctx->priv.gcm.nonce; |
| |
| memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); |
| memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); |
| |
| return gcm_aes_nx_crypt(req, 1); |
| } |
| |
| static int gcm4106_aes_nx_decrypt(struct aead_request *req) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm); |
| char *iv = nx_ctx->priv.gcm.iv; |
| char *nonce = nx_ctx->priv.gcm.nonce; |
| |
| memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); |
| memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); |
| |
| return gcm_aes_nx_crypt(req, 0); |
| } |
| |
| /* tell the block cipher walk routines that this is a stream cipher by |
| * setting cra_blocksize to 1. Even using blkcipher_walk_virt_block |
| * during encrypt/decrypt doesn't solve this problem, because it calls |
| * blkcipher_walk_done under the covers, which doesn't use walk->blocksize, |
| * but instead uses this tfm->blocksize. */ |
| struct crypto_alg nx_gcm_aes_alg = { |
| .cra_name = "gcm(aes)", |
| .cra_driver_name = "gcm-aes-nx", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_TYPE_AEAD, |
| .cra_blocksize = 1, |
| .cra_ctxsize = sizeof(struct nx_crypto_ctx), |
| .cra_type = &crypto_aead_type, |
| .cra_module = THIS_MODULE, |
| .cra_init = nx_crypto_ctx_aes_gcm_init, |
| .cra_exit = nx_crypto_ctx_exit, |
| .cra_aead = { |
| .ivsize = AES_BLOCK_SIZE, |
| .maxauthsize = AES_BLOCK_SIZE, |
| .setkey = gcm_aes_nx_set_key, |
| .setauthsize = gcm_aes_nx_setauthsize, |
| .encrypt = gcm_aes_nx_encrypt, |
| .decrypt = gcm_aes_nx_decrypt, |
| } |
| }; |
| |
| struct crypto_alg nx_gcm4106_aes_alg = { |
| .cra_name = "rfc4106(gcm(aes))", |
| .cra_driver_name = "rfc4106-gcm-aes-nx", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_TYPE_AEAD, |
| .cra_blocksize = 1, |
| .cra_ctxsize = sizeof(struct nx_crypto_ctx), |
| .cra_type = &crypto_nivaead_type, |
| .cra_module = THIS_MODULE, |
| .cra_init = nx_crypto_ctx_aes_gcm_init, |
| .cra_exit = nx_crypto_ctx_exit, |
| .cra_aead = { |
| .ivsize = 8, |
| .maxauthsize = AES_BLOCK_SIZE, |
| .geniv = "seqiv", |
| .setkey = gcm4106_aes_nx_set_key, |
| .setauthsize = gcm4106_aes_nx_setauthsize, |
| .encrypt = gcm4106_aes_nx_encrypt, |
| .decrypt = gcm4106_aes_nx_decrypt, |
| } |
| }; |