summaryrefslogtreecommitdiff
path: root/drivers/crypto/nx/nx-aes-xcbc.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/crypto/nx/nx-aes-xcbc.c')
-rw-r--r--drivers/crypto/nx/nx-aes-xcbc.c378
1 files changed, 378 insertions, 0 deletions
diff --git a/drivers/crypto/nx/nx-aes-xcbc.c b/drivers/crypto/nx/nx-aes-xcbc.c
new file mode 100644
index 000000000..8c2faffab
--- /dev/null
+++ b/drivers/crypto/nx/nx-aes-xcbc.c
@@ -0,0 +1,378 @@
+/**
+ * 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;
+}
+
+/*
+ * Based on RFC 3566, for a zero-length message:
+ *
+ * n = 1
+ * K1 = E(K, 0x01010101010101010101010101010101)
+ * K3 = E(K, 0x03030303030303030303030303030303)
+ * E[0] = 0x00000000000000000000000000000000
+ * M[1] = 0x80000000000000000000000000000000 (0 length message with padding)
+ * E[1] = (K1, M[1] ^ E[0] ^ K3)
+ * Tag = M[1]
+ */
+static int nx_xcbc_empty(struct shash_desc *desc, u8 *out)
+{
+ 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;
+ u8 keys[2][AES_BLOCK_SIZE];
+ u8 key[32];
+ int rc = 0;
+ int len;
+
+ /* Change to ECB mode */
+ csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB;
+ memcpy(key, csbcpb->cpb.aes_xcbc.key, AES_BLOCK_SIZE);
+ memcpy(csbcpb->cpb.aes_ecb.key, key, AES_BLOCK_SIZE);
+ NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
+
+ /* K1 and K3 base patterns */
+ memset(keys[0], 0x01, sizeof(keys[0]));
+ memset(keys[1], 0x03, sizeof(keys[1]));
+
+ len = sizeof(keys);
+ /* Generate K1 and K3 encrypting the patterns */
+ in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) keys, &len,
+ nx_ctx->ap->sglen);
+
+ if (len != sizeof(keys))
+ return -EINVAL;
+
+ out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) keys, &len,
+ nx_ctx->ap->sglen);
+
+ if (len != sizeof(keys))
+ 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));
+
+ /* XOr K3 with the padding for a 0 length message */
+ keys[1][0] ^= 0x80;
+
+ len = sizeof(keys[1]);
+
+ /* Encrypt the final result */
+ memcpy(csbcpb->cpb.aes_ecb.key, keys[0], AES_BLOCK_SIZE);
+ in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) keys[1], &len,
+ nx_ctx->ap->sglen);
+
+ if (len != sizeof(keys[1]))
+ return -EINVAL;
+
+ len = AES_BLOCK_SIZE;
+ out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len,
+ nx_ctx->ap->sglen);
+
+ if (len != AES_BLOCK_SIZE)
+ 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));
+
+out:
+ /* Restore XCBC mode */
+ csbcpb->cpb.hdr.mode = NX_MODE_AES_XCBC_MAC;
+ memcpy(csbcpb->cpb.aes_xcbc.key, key, AES_BLOCK_SIZE);
+ NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
+
+ return rc;
+}
+
+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;
+ int len;
+
+ 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);
+
+ len = AES_BLOCK_SIZE;
+ out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
+ &len, nx_ctx->ap->sglen);
+
+ if (len != AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ 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 = 0, leftover, total;
+ unsigned int max_sg_len;
+ unsigned long irq_flags;
+ int rc = 0;
+ int data_len;
+
+ spin_lock_irqsave(&nx_ctx->lock, irq_flags);
+
+
+ total = sctx->count + len;
+
+ /* 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 (total <= AES_BLOCK_SIZE) {
+ memcpy(sctx->buffer + sctx->count, data, len);
+ sctx->count += len;
+ goto out;
+ }
+
+ in_sg = nx_ctx->in_sg;
+ 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 = total - to_process;
+ to_process = to_process & ~(AES_BLOCK_SIZE - 1);
+
+ leftover = total - to_process;
+
+ /* 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) {
+ data_len = sctx->count;
+ in_sg = nx_build_sg_list(nx_ctx->in_sg,
+ (u8 *) sctx->buffer,
+ &data_len,
+ max_sg_len);
+ if (data_len != sctx->count)
+ return -EINVAL;
+ }
+
+ data_len = to_process - sctx->count;
+ in_sg = nx_build_sg_list(in_sg,
+ (u8 *) data,
+ &data_len,
+ max_sg_len);
+
+ if (data_len != to_process - sctx->count)
+ return -EINVAL;
+
+ nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) *
+ sizeof(struct nx_sg);
+
+ /* we've hit the nx chip previously and we're updating again,
+ * so copy over the partial digest */
+ if (NX_CPB_FDM(csbcpb) & NX_FDM_CONTINUATION) {
+ memcpy(csbcpb->cpb.aes_xcbc.cv,
+ csbcpb->cpb.aes_xcbc.out_cv_mac,
+ AES_BLOCK_SIZE);
+ }
+
+ 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));
+
+ /* everything after the first update is continuation */
+ NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
+
+ total -= to_process;
+ data += to_process - sctx->count;
+ sctx->count = 0;
+ in_sg = nx_ctx->in_sg;
+ } while (leftover > AES_BLOCK_SIZE);
+
+ /* copy the leftover back into the state struct */
+ memcpy(sctx->buffer, data, leftover);
+ sctx->count = leftover;
+
+out:
+ spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
+ 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;
+ unsigned long irq_flags;
+ int rc = 0;
+ int len;
+
+ spin_lock_irqsave(&nx_ctx->lock, irq_flags);
+
+ 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 ECB to
+ * generate the hash.
+ */
+ rc = nx_xcbc_empty(desc, out);
+ 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;
+
+ len = sctx->count;
+ in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *)sctx->buffer,
+ &len, nx_ctx->ap->sglen);
+
+ if (len != sctx->count)
+ return -EINVAL;
+
+ len = AES_BLOCK_SIZE;
+ out_sg = nx_build_sg_list(nx_ctx->out_sg, out, &len,
+ nx_ctx->ap->sglen);
+
+ if (len != AES_BLOCK_SIZE)
+ 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);
+
+ 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:
+ spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
+ 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,
+ }
+};