summaryrefslogtreecommitdiff
path: root/drivers/crypto/nx/nx-aes-gcm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/crypto/nx/nx-aes-gcm.c')
-rw-r--r--drivers/crypto/nx/nx-aes-gcm.c525
1 files changed, 525 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..88c562434
--- /dev/null
+++ b/drivers/crypto/nx/nx-aes-gcm.c
@@ -0,0 +1,525 @@
+/**
+ * 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)
+{
+ 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 = req->assoclen;
+ unsigned int processed = 0, to_process;
+ unsigned int max_sg_len;
+
+ if (nbytes <= AES_BLOCK_SIZE) {
+ scatterwalk_start(&walk, req->assoc);
+ 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->assoc, 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(req->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)
+{
+ int rc;
+ struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
+ struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
+ struct nx_sg *nx_sg;
+ unsigned int nbytes = req->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->assoc, 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(req->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_tfm_ctx(req->base.tfm);
+ 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)
+{
+ 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;
+ unsigned int processed = 0, to_process;
+ unsigned long irq_flags;
+ int rc = -EINVAL;
+
+ spin_lock_irqsave(&nx_ctx->lock, irq_flags);
+
+ desc.info = nx_ctx->priv.gcm.iv;
+ /* initialize the counter */
+ *(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1;
+
+ if (nbytes == 0) {
+ if (req->assoclen == 0)
+ rc = gcm_empty(req, &desc, enc);
+ else
+ rc = gmac(req, &desc);
+ if (rc)
+ goto out;
+ else
+ goto mac;
+ }
+
+ /* Process associated data */
+ 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;
+ }
+
+ /* 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;
+ desc.tfm = (struct crypto_blkcipher *) req->base.tfm;
+ rc = nx_build_sg_lists(nx_ctx, &desc, req->dst,
+ req->src, &to_process, processed,
+ 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, 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, 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:
+ spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
+ 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,
+ }
+};