1 files changed, 395 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..ad3358e74
--- /dev/null
+++ b/drivers/crypto/nx/nx-aes-xcbc.c
@@ -0,0 +1,395 @@
+/**
+ * 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);
+	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
+
+	switch (key_len) {
+	case AES_KEYSIZE_128:
+		nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	memcpy(csbcpb->cpb.aes_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_crypto_ctx_aes_xcbc_init2(struct crypto_tfm *tfm)
+{
+	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
+	struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
+	int err;
+
+	err = nx_crypto_ctx_aes_xcbc_init(tfm);
+	if (err)
+		return err;
+
+	nx_ctx_init(nx_ctx, HCOP_FC_AES);
+
+	NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
+	csbcpb->cpb.hdr.mode = NX_MODE_AES_XCBC_MAC;
+
+	return 0;
+}
+
+static int nx_xcbc_init(struct shash_desc *desc)
+{
+	struct xcbc_state *sctx = shash_desc_ctx(desc);
+
+	memset(sctx, 0, sizeof *sctx);
+
+	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;
+	struct nx_sg *out_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);
+
+	data_len = AES_BLOCK_SIZE;
+	out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *)sctx->state,
+				  &len, nx_ctx->ap->sglen);
+
+	if (data_len != AES_BLOCK_SIZE) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
+
+	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) {
+				rc = -EINVAL;
+				goto out;
+			}
+		}
+
+		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) {
+			rc = -EINVAL;
+			goto out;
+		}
+
+		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) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	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) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	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_blocksize   = AES_BLOCK_SIZE,
+		.cra_module      = THIS_MODULE,
+		.cra_ctxsize     = sizeof(struct nx_crypto_ctx),
+		.cra_init        = nx_crypto_ctx_aes_xcbc_init2,
+		.cra_exit        = nx_crypto_ctx_exit,
+	}
+};