diff options
Diffstat (limited to 'drivers/crypto/nx/nx-aes-gcm.c')
| -rw-r--r-- | drivers/crypto/nx/nx-aes-gcm.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/drivers/crypto/nx/nx-aes-gcm.c b/drivers/crypto/nx/nx-aes-gcm.c new file mode 100644 index 000000000..a810596b9 --- /dev/null +++ b/drivers/crypto/nx/nx-aes-gcm.c @@ -0,0 +1,526 @@ +/** + * 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/gcm.h> +#include <crypto/scatterwalk.h> +#include <linux/module.h> +#include <linux/types.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_aead_ctx(tfm); + 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_aead_ctx(tfm); + 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 gcm4106_aes_nx_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 8: + case 12: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + +static int nx_gca(struct nx_crypto_ctx *nx_ctx, + struct aead_request *req, + u8 *out, + unsigned int assoclen) +{ + int rc; + struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead; + struct scatter_walk walk; + struct nx_sg *nx_sg = nx_ctx->in_sg; + unsigned int nbytes = assoclen; + unsigned int processed = 0, to_process; + unsigned int max_sg_len; + + if (nbytes <= AES_BLOCK_SIZE) { + scatterwalk_start(&walk, req->src); + scatterwalk_copychunks(out, &walk, nbytes, SCATTERWALK_FROM_SG); + scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0); + return 0; + } + + NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_CONTINUATION; + + /* page_limit: number of sg entries that fit on one page */ + max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), + nx_ctx->ap->sglen); + max_sg_len = min_t(u64, max_sg_len, + nx_ctx->ap->databytelen/NX_PAGE_SIZE); + + do { + /* + * to_process: the data chunk to process in this update. + * This value is bound by sg list limits. + */ + to_process = min_t(u64, nbytes - processed, + nx_ctx->ap->databytelen); + to_process = min_t(u64, to_process, + NX_PAGE_SIZE * (max_sg_len - 1)); + + nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, + req->src, processed, &to_process); + + if ((to_process + processed) < nbytes) + NX_CPB_FDM(csbcpb_aead) |= NX_FDM_INTERMEDIATE; + else + NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_INTERMEDIATE; + + 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) + return rc; + + memcpy(csbcpb_aead->cpb.aes_gca.in_pat, + csbcpb_aead->cpb.aes_gca.out_pat, + AES_BLOCK_SIZE); + NX_CPB_FDM(csbcpb_aead) |= NX_FDM_CONTINUATION; + + atomic_inc(&(nx_ctx->stats->aes_ops)); + atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); + + processed += to_process; + } while (processed < nbytes); + + memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE); + + return rc; +} + +static int gmac(struct aead_request *req, struct blkcipher_desc *desc, + unsigned int assoclen) +{ + int rc; + struct nx_crypto_ctx *nx_ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; + struct nx_sg *nx_sg; + unsigned int nbytes = assoclen; + unsigned int processed = 0, to_process; + unsigned int max_sg_len; + + /* Set GMAC mode */ + csbcpb->cpb.hdr.mode = NX_MODE_AES_GMAC; + + NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; + + /* page_limit: number of sg entries that fit on one page */ + max_sg_len = min_t(u64, nx_driver.of.max_sg_len/sizeof(struct nx_sg), + nx_ctx->ap->sglen); + max_sg_len = min_t(u64, max_sg_len, + nx_ctx->ap->databytelen/NX_PAGE_SIZE); + + /* Copy IV */ + memcpy(csbcpb->cpb.aes_gcm.iv_or_cnt, desc->info, AES_BLOCK_SIZE); + + do { + /* + * to_process: the data chunk to process in this update. + * This value is bound by sg list limits. + */ + to_process = min_t(u64, nbytes - processed, + nx_ctx->ap->databytelen); + to_process = min_t(u64, to_process, + NX_PAGE_SIZE * (max_sg_len - 1)); + + nx_sg = nx_walk_and_build(nx_ctx->in_sg, max_sg_len, + req->src, processed, &to_process); + + if ((to_process + processed) < nbytes) + NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; + else + NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; + + nx_ctx->op.inlen = (nx_ctx->in_sg - nx_sg) + * sizeof(struct nx_sg); + + csbcpb->cpb.aes_gcm.bit_length_data = 0; + csbcpb->cpb.aes_gcm.bit_length_aad = 8 * nbytes; + + rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, + req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); + if (rc) + goto out; + + memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, + csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); + memcpy(csbcpb->cpb.aes_gcm.in_s0, + csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); + + NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; + + atomic_inc(&(nx_ctx->stats->aes_ops)); + atomic64_add(assoclen, &(nx_ctx->stats->aes_bytes)); + + processed += to_process; + } while (processed < nbytes); + +out: + /* Restore GCM mode */ + csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; + return rc; +} + +static int gcm_empty(struct aead_request *req, struct blkcipher_desc *desc, + int enc) +{ + int rc; + struct nx_crypto_ctx *nx_ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; + char out[AES_BLOCK_SIZE]; + struct nx_sg *in_sg, *out_sg; + int len; + + /* 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 */ + + /* Change to ECB mode */ + csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB; + memcpy(csbcpb->cpb.aes_ecb.key, csbcpb->cpb.aes_gcm.key, + sizeof(csbcpb->cpb.aes_ecb.key)); + if (enc) + NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; + else + NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; + + len = AES_BLOCK_SIZE; + + /* Encrypt the counter/IV */ + in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) desc->info, + &len, nx_ctx->ap->sglen); + + if (len != AES_BLOCK_SIZE) + return -EINVAL; + + len = sizeof(out); + out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) out, &len, + nx_ctx->ap->sglen); + + if (len != sizeof(out)) + return -EINVAL; + + nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg); + nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg); + + rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, + desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP); + if (rc) + goto out; + atomic_inc(&(nx_ctx->stats->aes_ops)); + + /* Copy out the auth tag */ + memcpy(csbcpb->cpb.aes_gcm.out_pat_or_mac, out, + crypto_aead_authsize(crypto_aead_reqtfm(req))); +out: + /* Restore XCBC mode */ + csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM; + + /* + * ECB key uses the same region that GCM AAD and counter, so it's safe + * to just fill it with zeroes. + */ + memset(csbcpb->cpb.aes_ecb.key, 0, sizeof(csbcpb->cpb.aes_ecb.key)); + + return rc; +} + +static int gcm_aes_nx_crypt(struct aead_request *req, int enc, + unsigned int assoclen) +{ + struct nx_crypto_ctx *nx_ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct nx_gcm_rctx *rctx = aead_request_ctx(req); + struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; + struct blkcipher_desc desc; + unsigned int nbytes = req->cryptlen; + unsigned int processed = 0, to_process; + unsigned long irq_flags; + int rc = -EINVAL; + + spin_lock_irqsave(&nx_ctx->lock, irq_flags); + + desc.info = rctx->iv; + /* initialize the counter */ + *(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1; + + if (nbytes == 0) { + if (assoclen == 0) + rc = gcm_empty(req, &desc, enc); + else + rc = gmac(req, &desc, assoclen); + if (rc) + goto out; + else + goto mac; + } + + /* Process associated data */ + csbcpb->cpb.aes_gcm.bit_length_aad = assoclen * 8; + if (assoclen) { + rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad, + assoclen); + if (rc) + goto out; + } + + /* Set flags for encryption */ + NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION; + if (enc) { + NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT; + } else { + NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT; + nbytes -= crypto_aead_authsize(crypto_aead_reqtfm(req)); + } + + do { + to_process = nbytes - processed; + + csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8; + rc = nx_build_sg_lists(nx_ctx, &desc, req->dst, + req->src, &to_process, + processed + req->assoclen, + csbcpb->cpb.aes_gcm.iv_or_cnt); + + if (rc) + goto out; + + if ((to_process + processed) < nbytes) + NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; + else + NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; + + + rc = nx_hcall_sync(nx_ctx, &nx_ctx->op, + req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); + if (rc) + goto out; + + memcpy(desc.info, csbcpb->cpb.aes_gcm.out_cnt, AES_BLOCK_SIZE); + memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad, + csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE); + memcpy(csbcpb->cpb.aes_gcm.in_s0, + csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE); + + NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; + + atomic_inc(&(nx_ctx->stats->aes_ops)); + atomic64_add(csbcpb->csb.processed_byte_count, + &(nx_ctx->stats->aes_bytes)); + + processed += to_process; + } while (processed < nbytes); + +mac: + if (enc) { + /* copy out the auth tag */ + scatterwalk_map_and_copy( + csbcpb->cpb.aes_gcm.out_pat_or_mac, + req->dst, req->assoclen + nbytes, + crypto_aead_authsize(crypto_aead_reqtfm(req)), + SCATTERWALK_TO_SG); + } else { + u8 *itag = nx_ctx->priv.gcm.iauth_tag; + u8 *otag = csbcpb->cpb.aes_gcm.out_pat_or_mac; + + scatterwalk_map_and_copy( + itag, req->src, req->assoclen + nbytes, + crypto_aead_authsize(crypto_aead_reqtfm(req)), + SCATTERWALK_FROM_SG); + rc = crypto_memneq(itag, otag, + crypto_aead_authsize(crypto_aead_reqtfm(req))) ? + -EBADMSG : 0; + } +out: + spin_unlock_irqrestore(&nx_ctx->lock, irq_flags); + return rc; +} + +static int gcm_aes_nx_encrypt(struct aead_request *req) +{ + struct nx_gcm_rctx *rctx = aead_request_ctx(req); + char *iv = rctx->iv; + + memcpy(iv, req->iv, GCM_AES_IV_SIZE); + + return gcm_aes_nx_crypt(req, 1, req->assoclen); +} + +static int gcm_aes_nx_decrypt(struct aead_request *req) +{ + struct nx_gcm_rctx *rctx = aead_request_ctx(req); + char *iv = rctx->iv; + + memcpy(iv, req->iv, GCM_AES_IV_SIZE); + + return gcm_aes_nx_crypt(req, 0, req->assoclen); +} + +static int gcm4106_aes_nx_encrypt(struct aead_request *req) +{ + struct nx_crypto_ctx *nx_ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct nx_gcm_rctx *rctx = aead_request_ctx(req); + char *iv = rctx->iv; + char *nonce = nx_ctx->priv.gcm.nonce; + + memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); + memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); + + if (req->assoclen < 8) + return -EINVAL; + + return gcm_aes_nx_crypt(req, 1, req->assoclen - 8); +} + +static int gcm4106_aes_nx_decrypt(struct aead_request *req) +{ + struct nx_crypto_ctx *nx_ctx = + crypto_aead_ctx(crypto_aead_reqtfm(req)); + struct nx_gcm_rctx *rctx = aead_request_ctx(req); + char *iv = rctx->iv; + char *nonce = nx_ctx->priv.gcm.nonce; + + memcpy(iv, nonce, NX_GCM4106_NONCE_LEN); + memcpy(iv + NX_GCM4106_NONCE_LEN, req->iv, 8); + + if (req->assoclen < 8) + return -EINVAL; + + return gcm_aes_nx_crypt(req, 0, req->assoclen - 8); +} + +/* 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 aead_alg nx_gcm_aes_alg = { + .base = { + .cra_name = "gcm(aes)", + .cra_driver_name = "gcm-aes-nx", + .cra_priority = 300, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct nx_crypto_ctx), + .cra_module = THIS_MODULE, + }, + .init = nx_crypto_ctx_aes_gcm_init, + .exit = nx_crypto_ctx_aead_exit, + .ivsize = GCM_AES_IV_SIZE, + .maxauthsize = AES_BLOCK_SIZE, + .setkey = gcm_aes_nx_set_key, + .encrypt = gcm_aes_nx_encrypt, + .decrypt = gcm_aes_nx_decrypt, +}; + +struct aead_alg nx_gcm4106_aes_alg = { + .base = { + .cra_name = "rfc4106(gcm(aes))", + .cra_driver_name = "rfc4106-gcm-aes-nx", + .cra_priority = 300, + .cra_blocksize = 1, + .cra_ctxsize = sizeof(struct nx_crypto_ctx), + .cra_module = THIS_MODULE, + }, + .init = nx_crypto_ctx_aes_gcm_init, + .exit = nx_crypto_ctx_aead_exit, + .ivsize = GCM_RFC4106_IV_SIZE, + .maxauthsize = AES_BLOCK_SIZE, + .setkey = gcm4106_aes_nx_set_key, + .setauthsize = gcm4106_aes_nx_setauthsize, + .encrypt = gcm4106_aes_nx_encrypt, + .decrypt = gcm4106_aes_nx_decrypt, +}; |