| /** |
| * AES XCBC routines supporting the Power 7+ Nest Accelerators driver |
| * |
| * Copyright (C) 2011-2012 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/hash.h> |
| #include <crypto/aes.h> |
| #include <crypto/algapi.h> |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/crypto.h> |
| #include <asm/vio.h> |
| |
| #include "nx_csbcpb.h" |
| #include "nx.h" |
| |
| |
| struct xcbc_state { |
| u8 state[AES_BLOCK_SIZE]; |
| unsigned int count; |
| u8 buffer[AES_BLOCK_SIZE]; |
| }; |
| |
| static int nx_xcbc_set_key(struct crypto_shash *desc, |
| const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct nx_crypto_ctx *nx_ctx = crypto_shash_ctx(desc); |
| |
| switch (key_len) { |
| case AES_KEYSIZE_128: |
| nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128]; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| memcpy(nx_ctx->priv.xcbc.key, in_key, key_len); |
| |
| return 0; |
| } |
| |
| static int nx_xcbc_init(struct shash_desc *desc) |
| { |
| struct xcbc_state *sctx = shash_desc_ctx(desc); |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base); |
| struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; |
| struct nx_sg *out_sg; |
| |
| nx_ctx_init(nx_ctx, HCOP_FC_AES); |
| |
| memset(sctx, 0, sizeof *sctx); |
| |
| NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128); |
| csbcpb->cpb.hdr.mode = NX_MODE_AES_XCBC_MAC; |
| |
| memcpy(csbcpb->cpb.aes_xcbc.key, nx_ctx->priv.xcbc.key, AES_BLOCK_SIZE); |
| memset(nx_ctx->priv.xcbc.key, 0, sizeof *nx_ctx->priv.xcbc.key); |
| |
| out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state, |
| AES_BLOCK_SIZE, nx_ctx->ap->sglen); |
| nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg); |
| |
| return 0; |
| } |
| |
| static int nx_xcbc_update(struct shash_desc *desc, |
| const u8 *data, |
| unsigned int len) |
| { |
| struct xcbc_state *sctx = shash_desc_ctx(desc); |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base); |
| struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; |
| struct nx_sg *in_sg; |
| u32 to_process, leftover; |
| int rc = 0; |
| |
| if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) { |
| /* we've hit the nx chip previously and we're updating again, |
| * so copy over the partial digest */ |
| memcpy(csbcpb->cpb.aes_xcbc.cv, |
| csbcpb->cpb.aes_xcbc.out_cv_mac, AES_BLOCK_SIZE); |
| } |
| |
| /* 2 cases for total data len: |
| * 1: <= AES_BLOCK_SIZE: copy into state, return 0 |
| * 2: > AES_BLOCK_SIZE: process X blocks, copy in leftover |
| */ |
| if (len + sctx->count <= AES_BLOCK_SIZE) { |
| memcpy(sctx->buffer + sctx->count, data, len); |
| sctx->count += len; |
| goto out; |
| } |
| |
| /* to_process: the AES_BLOCK_SIZE data chunk to process in this |
| * update */ |
| to_process = (sctx->count + len) & ~(AES_BLOCK_SIZE - 1); |
| leftover = (sctx->count + len) & (AES_BLOCK_SIZE - 1); |
| |
| /* the hardware will not accept a 0 byte operation for this algorithm |
| * and the operation MUST be finalized to be correct. So if we happen |
| * to get an update that falls on a block sized boundary, we must |
| * save off the last block to finalize with later. */ |
| if (!leftover) { |
| to_process -= AES_BLOCK_SIZE; |
| leftover = AES_BLOCK_SIZE; |
| } |
| |
| if (sctx->count) { |
| in_sg = nx_build_sg_list(nx_ctx->in_sg, sctx->buffer, |
| sctx->count, nx_ctx->ap->sglen); |
| in_sg = nx_build_sg_list(in_sg, (u8 *)data, |
| to_process - sctx->count, |
| nx_ctx->ap->sglen); |
| nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * |
| sizeof(struct nx_sg); |
| } else { |
| in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)data, to_process, |
| nx_ctx->ap->sglen); |
| nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * |
| sizeof(struct nx_sg); |
| } |
| |
| NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE; |
| |
| if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) { |
| rc = -EINVAL; |
| goto out; |
| } |
| |
| 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 the leftover back into the state struct */ |
| memcpy(sctx->buffer, data + len - leftover, leftover); |
| sctx->count = leftover; |
| |
| /* everything after the first update is continuation */ |
| NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION; |
| out: |
| return rc; |
| } |
| |
| static int nx_xcbc_final(struct shash_desc *desc, u8 *out) |
| { |
| struct xcbc_state *sctx = shash_desc_ctx(desc); |
| struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(&desc->tfm->base); |
| struct nx_csbcpb *csbcpb = nx_ctx->csbcpb; |
| struct nx_sg *in_sg, *out_sg; |
| int rc = 0; |
| |
| if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) { |
| /* we've hit the nx chip previously, now we're finalizing, |
| * so copy over the partial digest */ |
| memcpy(csbcpb->cpb.aes_xcbc.cv, |
| csbcpb->cpb.aes_xcbc.out_cv_mac, AES_BLOCK_SIZE); |
| } else if (sctx->count == 0) { |
| /* we've never seen an update, so this is a 0 byte op. The |
| * hardware cannot handle a 0 byte op, so just copy out the |
| * known 0 byte result. This is cheaper than allocating a |
| * software context to do a 0 byte op */ |
| u8 data[] = { 0x75, 0xf0, 0x25, 0x1d, 0x52, 0x8a, 0xc0, 0x1c, |
| 0x45, 0x73, 0xdf, 0xd5, 0x84, 0xd7, 0x9f, 0x29 }; |
| memcpy(out, data, sizeof(data)); |
| goto out; |
| } |
| |
| /* final is represented by continuing the operation and indicating that |
| * this is not an intermediate operation */ |
| NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE; |
| |
| in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buffer, |
| sctx->count, nx_ctx->ap->sglen); |
| out_sg = nx_build_sg_list(nx_ctx->out_sg, out, AES_BLOCK_SIZE, |
| nx_ctx->ap->sglen); |
| |
| 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); |
| |
| if (!nx_ctx->op.outlen) { |
| rc = -EINVAL; |
| goto out; |
| } |
| |
| 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)); |
| |
| memcpy(out, csbcpb->cpb.aes_xcbc.out_cv_mac, AES_BLOCK_SIZE); |
| out: |
| return rc; |
| } |
| |
| struct shash_alg nx_shash_aes_xcbc_alg = { |
| .digestsize = AES_BLOCK_SIZE, |
| .init = nx_xcbc_init, |
| .update = nx_xcbc_update, |
| .final = nx_xcbc_final, |
| .setkey = nx_xcbc_set_key, |
| .descsize = sizeof(struct xcbc_state), |
| .statesize = sizeof(struct xcbc_state), |
| .base = { |
| .cra_name = "xcbc(aes)", |
| .cra_driver_name = "xcbc-aes-nx", |
| .cra_priority = 300, |
| .cra_flags = CRYPTO_ALG_TYPE_SHASH, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_module = THIS_MODULE, |
| .cra_ctxsize = sizeof(struct nx_crypto_ctx), |
| .cra_init = nx_crypto_ctx_aes_xcbc_init, |
| .cra_exit = nx_crypto_ctx_exit, |
| } |
| }; |