crypto: ccp - CCP AES crypto API support

These routines provide crypto API support for AES on the AMD CCP.

Support for AES modes: ECB, CBC, OFB, CFB and CTR

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 375 insertions, 0 deletions

diff --git a/drivers/crypto/ccp/ccp-crypto-aes.c b/drivers/crypto/ccp/ccp-crypto-aes.c
new file mode 100644
index 000000000000..f302a5b7473b
--- /dev/null
+++ b/drivers/crypto/ccp/ccp-crypto-aes.c
@@ -0,0 +1,375 @@
+/*
+ * AMD Cryptographic Coprocessor (CCP) AES crypto API support
+ *
+ * Copyright (C) 2013 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/scatterlist.h>
+#include <linux/crypto.h>
+#include <crypto/algapi.h>
+#include <crypto/aes.h>
+#include <crypto/ctr.h>
+#include <crypto/scatterwalk.h>
+
+#include "ccp-crypto.h"
+
+
+static int ccp_aes_complete(struct crypto_async_request *async_req, int ret)
+{
+        struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
+        struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+        struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
+
+        if (ret)
+                return ret;
+
+        if (ctx->u.aes.mode != CCP_AES_MODE_ECB)
+                memcpy(req->info, rctx->iv, AES_BLOCK_SIZE);
+
+        return 0;
+}
+
+static int ccp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+                          unsigned int key_len)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
+        struct ccp_crypto_ablkcipher_alg *alg =
+                ccp_crypto_ablkcipher_alg(crypto_ablkcipher_tfm(tfm));
+
+        switch (key_len) {
+        case AES_KEYSIZE_128:
+                ctx->u.aes.type = CCP_AES_TYPE_128;
+                break;
+        case AES_KEYSIZE_192:
+                ctx->u.aes.type = CCP_AES_TYPE_192;
+                break;
+        case AES_KEYSIZE_256:
+                ctx->u.aes.type = CCP_AES_TYPE_256;
+                break;
+        default:
+                crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+                return -EINVAL;
+        }
+        ctx->u.aes.mode = alg->mode;
+        ctx->u.aes.key_len = key_len;
+
+        memcpy(ctx->u.aes.key, key, key_len);
+        sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
+
+        return 0;
+}
+
+static int ccp_aes_crypt(struct ablkcipher_request *req, bool encrypt)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+        struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
+        struct scatterlist *iv_sg = NULL;
+        unsigned int iv_len = 0;
+        int ret;
+
+        if (!ctx->u.aes.key_len) {
+                pr_err("AES key not set\n");
+                return -EINVAL;
+        }
+
+        if (((ctx->u.aes.mode == CCP_AES_MODE_ECB) ||
+             (ctx->u.aes.mode == CCP_AES_MODE_CBC) ||
+             (ctx->u.aes.mode == CCP_AES_MODE_CFB)) &&
+            (req->nbytes & (AES_BLOCK_SIZE - 1))) {
+                pr_err("AES request size is not a multiple of the block size\n");
+                return -EINVAL;
+        }
+
+        if (ctx->u.aes.mode != CCP_AES_MODE_ECB) {
+                if (!req->info) {
+                        pr_err("AES IV not supplied");
+                        return -EINVAL;
+                }
+
+                memcpy(rctx->iv, req->info, AES_BLOCK_SIZE);
+                iv_sg = &rctx->iv_sg;
+                iv_len = AES_BLOCK_SIZE;
+                sg_init_one(iv_sg, rctx->iv, iv_len);
+        }
+
+        memset(&rctx->cmd, 0, sizeof(rctx->cmd));
+        INIT_LIST_HEAD(&rctx->cmd.entry);
+        rctx->cmd.engine = CCP_ENGINE_AES;
+        rctx->cmd.u.aes.type = ctx->u.aes.type;
+        rctx->cmd.u.aes.mode = ctx->u.aes.mode;
+        rctx->cmd.u.aes.action =
+                (encrypt) ? CCP_AES_ACTION_ENCRYPT : CCP_AES_ACTION_DECRYPT;
+        rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
+        rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
+        rctx->cmd.u.aes.iv = iv_sg;
+        rctx->cmd.u.aes.iv_len = iv_len;
+        rctx->cmd.u.aes.src = req->src;
+        rctx->cmd.u.aes.src_len = req->nbytes;
+        rctx->cmd.u.aes.dst = req->dst;
+
+        ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
+
+        return ret;
+}
+
+static int ccp_aes_encrypt(struct ablkcipher_request *req)
+{
+        return ccp_aes_crypt(req, true);
+}
+
+static int ccp_aes_decrypt(struct ablkcipher_request *req)
+{
+        return ccp_aes_crypt(req, false);
+}
+
+static int ccp_aes_cra_init(struct crypto_tfm *tfm)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
+
+        ctx->complete = ccp_aes_complete;
+        ctx->u.aes.key_len = 0;
+
+        tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
+
+        return 0;
+}
+
+static void ccp_aes_cra_exit(struct crypto_tfm *tfm)
+{
+}
+
+static int ccp_aes_rfc3686_complete(struct crypto_async_request *async_req,
+                                    int ret)
+{
+        struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
+        struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
+
+        /* Restore the original pointer */
+        req->info = rctx->rfc3686_info;
+
+        return ccp_aes_complete(async_req, ret);
+}
+
+static int ccp_aes_rfc3686_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+                                  unsigned int key_len)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
+
+        if (key_len < CTR_RFC3686_NONCE_SIZE)
+                return -EINVAL;
+
+        key_len -= CTR_RFC3686_NONCE_SIZE;
+        memcpy(ctx->u.aes.nonce, key + key_len, CTR_RFC3686_NONCE_SIZE);
+
+        return ccp_aes_setkey(tfm, key, key_len);
+}
+
+static int ccp_aes_rfc3686_crypt(struct ablkcipher_request *req, bool encrypt)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+        struct ccp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
+        u8 *iv;
+
+        /* Initialize the CTR block */
+        iv = rctx->rfc3686_iv;
+        memcpy(iv, ctx->u.aes.nonce, CTR_RFC3686_NONCE_SIZE);
+
+        iv += CTR_RFC3686_NONCE_SIZE;
+        memcpy(iv, req->info, CTR_RFC3686_IV_SIZE);
+
+        iv += CTR_RFC3686_IV_SIZE;
+        *(__be32 *)iv = cpu_to_be32(1);
+
+        /* Point to the new IV */
+        rctx->rfc3686_info = req->info;
+        req->info = rctx->rfc3686_iv;
+
+        return ccp_aes_crypt(req, encrypt);
+}
+
+static int ccp_aes_rfc3686_encrypt(struct ablkcipher_request *req)
+{
+        return ccp_aes_rfc3686_crypt(req, true);
+}
+
+static int ccp_aes_rfc3686_decrypt(struct ablkcipher_request *req)
+{
+        return ccp_aes_rfc3686_crypt(req, false);
+}
+
+static int ccp_aes_rfc3686_cra_init(struct crypto_tfm *tfm)
+{
+        struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
+
+        ctx->complete = ccp_aes_rfc3686_complete;
+        ctx->u.aes.key_len = 0;
+
+        tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_aes_req_ctx);
+
+        return 0;
+}
+
+static void ccp_aes_rfc3686_cra_exit(struct crypto_tfm *tfm)
+{
+}
+
+static struct crypto_alg ccp_aes_defaults = {
+        .cra_flags      = CRYPTO_ALG_TYPE_ABLKCIPHER |
+                          CRYPTO_ALG_ASYNC |
+                          CRYPTO_ALG_KERN_DRIVER_ONLY |
+                          CRYPTO_ALG_NEED_FALLBACK,
+        .cra_blocksize  = AES_BLOCK_SIZE,
+        .cra_ctxsize    = sizeof(struct ccp_ctx),
+        .cra_priority   = CCP_CRA_PRIORITY,
+        .cra_type       = &crypto_ablkcipher_type,
+        .cra_init       = ccp_aes_cra_init,
+        .cra_exit       = ccp_aes_cra_exit,
+        .cra_module     = THIS_MODULE,
+        .cra_ablkcipher = {
+                .setkey         = ccp_aes_setkey,
+                .encrypt        = ccp_aes_encrypt,
+                .decrypt        = ccp_aes_decrypt,
+                .min_keysize    = AES_MIN_KEY_SIZE,
+                .max_keysize    = AES_MAX_KEY_SIZE,
+        },
+};
+
+static struct crypto_alg ccp_aes_rfc3686_defaults = {
+        .cra_flags      = CRYPTO_ALG_TYPE_ABLKCIPHER |
+                           CRYPTO_ALG_ASYNC |
+                           CRYPTO_ALG_KERN_DRIVER_ONLY |
+                           CRYPTO_ALG_NEED_FALLBACK,
+        .cra_blocksize  = CTR_RFC3686_BLOCK_SIZE,
+        .cra_ctxsize    = sizeof(struct ccp_ctx),
+        .cra_priority   = CCP_CRA_PRIORITY,
+        .cra_type       = &crypto_ablkcipher_type,
+        .cra_init       = ccp_aes_rfc3686_cra_init,
+        .cra_exit       = ccp_aes_rfc3686_cra_exit,
+        .cra_module     = THIS_MODULE,
+        .cra_ablkcipher = {
+                .setkey         = ccp_aes_rfc3686_setkey,
+                .encrypt        = ccp_aes_rfc3686_encrypt,
+                .decrypt        = ccp_aes_rfc3686_decrypt,
+                .min_keysize    = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
+                .max_keysize    = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
+        },
+};
+
+struct ccp_aes_def {
+        enum ccp_aes_mode mode;
+        const char *name;
+        const char *driver_name;
+        unsigned int blocksize;
+        unsigned int ivsize;
+        struct crypto_alg *alg_defaults;
+};
+
+static struct ccp_aes_def aes_algs[] = {
+        {
+                .mode           = CCP_AES_MODE_ECB,
+                .name           = "ecb(aes)",
+                .driver_name    = "ecb-aes-ccp",
+                .blocksize      = AES_BLOCK_SIZE,
+                .ivsize         = 0,
+                .alg_defaults   = &ccp_aes_defaults,
+        },
+        {
+                .mode           = CCP_AES_MODE_CBC,
+                .name           = "cbc(aes)",
+                .driver_name    = "cbc-aes-ccp",
+                .blocksize      = AES_BLOCK_SIZE,
+                .ivsize         = AES_BLOCK_SIZE,
+                .alg_defaults   = &ccp_aes_defaults,
+        },
+        {
+                .mode           = CCP_AES_MODE_CFB,
+                .name           = "cfb(aes)",
+                .driver_name    = "cfb-aes-ccp",
+                .blocksize      = AES_BLOCK_SIZE,
+                .ivsize         = AES_BLOCK_SIZE,
+                .alg_defaults   = &ccp_aes_defaults,
+        },
+        {
+                .mode           = CCP_AES_MODE_OFB,
+                .name           = "ofb(aes)",
+                .driver_name    = "ofb-aes-ccp",
+                .blocksize      = 1,
+                .ivsize         = AES_BLOCK_SIZE,
+                .alg_defaults   = &ccp_aes_defaults,
+        },
+        {
+                .mode           = CCP_AES_MODE_CTR,
+                .name           = "ctr(aes)",
+                .driver_name    = "ctr-aes-ccp",
+                .blocksize      = 1,
+                .ivsize         = AES_BLOCK_SIZE,
+                .alg_defaults   = &ccp_aes_defaults,
+        },
+        {
+                .mode           = CCP_AES_MODE_CTR,
+                .name           = "rfc3686(ctr(aes))",
+                .driver_name    = "rfc3686-ctr-aes-ccp",
+                .blocksize      = 1,
+                .ivsize         = CTR_RFC3686_IV_SIZE,
+                .alg_defaults   = &ccp_aes_rfc3686_defaults,
+        },
+};
+
+static int ccp_register_aes_alg(struct list_head *head,
+                                const struct ccp_aes_def *def)
+{
+        struct ccp_crypto_ablkcipher_alg *ccp_alg;
+        struct crypto_alg *alg;
+        int ret;
+
+        ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
+        if (!ccp_alg)
+                return -ENOMEM;
+
+        INIT_LIST_HEAD(&ccp_alg->entry);
+
+        ccp_alg->mode = def->mode;
+
+        /* Copy the defaults and override as necessary */
+        alg = &ccp_alg->alg;
+        memcpy(alg, def->alg_defaults, sizeof(*alg));
+        snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
+        snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
+                 def->driver_name);
+        alg->cra_blocksize = def->blocksize;
+        alg->cra_ablkcipher.ivsize = def->ivsize;
+
+        ret = crypto_register_alg(alg);
+        if (ret) {
+                pr_err("%s ablkcipher algorithm registration error (%d)\n",
+                        alg->cra_name, ret);
+                kfree(ccp_alg);
+                return ret;
+        }
+
+        list_add(&ccp_alg->entry, head);
+
+        return 0;
+}
+
+int ccp_register_aes_algs(struct list_head *head)
+{
+        int i, ret;
+
+        for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
+                ret = ccp_register_aes_alg(head, &aes_algs[i]);
+                if (ret)
+                        return ret;
+        }
+
+        return 0;
+}