summaryrefslogtreecommitdiffstats
path: root/drivers/crypto/omap-aes-gcm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/crypto/omap-aes-gcm.c')
-rw-r--r--drivers/crypto/omap-aes-gcm.c388
1 files changed, 388 insertions, 0 deletions
diff --git a/drivers/crypto/omap-aes-gcm.c b/drivers/crypto/omap-aes-gcm.c
new file mode 100644
index 0000000000..c498950402
--- /dev/null
+++ b/drivers/crypto/omap-aes-gcm.c
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Cryptographic API.
+ *
+ * Support for OMAP AES GCM HW acceleration.
+ *
+ * Copyright (c) 2016 Texas Instruments Incorporated
+ */
+
+#include <crypto/aes.h>
+#include <crypto/engine.h>
+#include <crypto/gcm.h>
+#include <crypto/internal/aead.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/skcipher.h>
+#include <linux/errno.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/omap-dma.h>
+#include <linux/pm_runtime.h>
+#include <linux/scatterlist.h>
+#include <linux/string.h>
+
+#include "omap-crypto.h"
+#include "omap-aes.h"
+
+static int omap_aes_gcm_handle_queue(struct omap_aes_dev *dd,
+ struct aead_request *req);
+
+static void omap_aes_gcm_finish_req(struct omap_aes_dev *dd, int ret)
+{
+ struct aead_request *req = dd->aead_req;
+
+ dd->in_sg = NULL;
+ dd->out_sg = NULL;
+
+ crypto_finalize_aead_request(dd->engine, req, ret);
+
+ pm_runtime_mark_last_busy(dd->dev);
+ pm_runtime_put_autosuspend(dd->dev);
+}
+
+static void omap_aes_gcm_done_task(struct omap_aes_dev *dd)
+{
+ u8 *tag;
+ int alen, clen, i, ret = 0, nsg;
+ struct omap_aes_reqctx *rctx;
+
+ alen = ALIGN(dd->assoc_len, AES_BLOCK_SIZE);
+ clen = ALIGN(dd->total, AES_BLOCK_SIZE);
+ rctx = aead_request_ctx(dd->aead_req);
+
+ nsg = !!(dd->assoc_len && dd->total);
+
+ dma_sync_sg_for_device(dd->dev, dd->out_sg, dd->out_sg_len,
+ DMA_FROM_DEVICE);
+ dma_unmap_sg(dd->dev, dd->in_sg, dd->in_sg_len, DMA_TO_DEVICE);
+ dma_unmap_sg(dd->dev, dd->out_sg, dd->out_sg_len, DMA_FROM_DEVICE);
+ omap_aes_crypt_dma_stop(dd);
+
+ omap_crypto_cleanup(dd->out_sg, dd->orig_out,
+ dd->aead_req->assoclen, dd->total,
+ FLAGS_OUT_DATA_ST_SHIFT, dd->flags);
+
+ if (dd->flags & FLAGS_ENCRYPT)
+ scatterwalk_map_and_copy(rctx->auth_tag,
+ dd->aead_req->dst,
+ dd->total + dd->aead_req->assoclen,
+ dd->authsize, 1);
+
+ omap_crypto_cleanup(&dd->in_sgl[0], NULL, 0, alen,
+ FLAGS_ASSOC_DATA_ST_SHIFT, dd->flags);
+
+ omap_crypto_cleanup(&dd->in_sgl[nsg], NULL, 0, clen,
+ FLAGS_IN_DATA_ST_SHIFT, dd->flags);
+
+ if (!(dd->flags & FLAGS_ENCRYPT)) {
+ tag = (u8 *)rctx->auth_tag;
+ for (i = 0; i < dd->authsize; i++) {
+ if (tag[i]) {
+ ret = -EBADMSG;
+ }
+ }
+ }
+
+ omap_aes_gcm_finish_req(dd, ret);
+}
+
+static int omap_aes_gcm_copy_buffers(struct omap_aes_dev *dd,
+ struct aead_request *req)
+{
+ int alen, clen, cryptlen, assoclen, ret;
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ unsigned int authlen = crypto_aead_authsize(aead);
+ struct scatterlist *tmp, sg_arr[2];
+ int nsg;
+ u16 flags;
+
+ assoclen = req->assoclen;
+ cryptlen = req->cryptlen;
+
+ if (dd->flags & FLAGS_RFC4106_GCM)
+ assoclen -= 8;
+
+ if (!(dd->flags & FLAGS_ENCRYPT))
+ cryptlen -= authlen;
+
+ alen = ALIGN(assoclen, AES_BLOCK_SIZE);
+ clen = ALIGN(cryptlen, AES_BLOCK_SIZE);
+
+ nsg = !!(assoclen && cryptlen);
+
+ omap_aes_clear_copy_flags(dd);
+
+ sg_init_table(dd->in_sgl, nsg + 1);
+ if (assoclen) {
+ tmp = req->src;
+ ret = omap_crypto_align_sg(&tmp, assoclen,
+ AES_BLOCK_SIZE, dd->in_sgl,
+ OMAP_CRYPTO_COPY_DATA |
+ OMAP_CRYPTO_ZERO_BUF |
+ OMAP_CRYPTO_FORCE_SINGLE_ENTRY,
+ FLAGS_ASSOC_DATA_ST_SHIFT,
+ &dd->flags);
+ if (ret)
+ return ret;
+ }
+
+ if (cryptlen) {
+ tmp = scatterwalk_ffwd(sg_arr, req->src, req->assoclen);
+
+ if (nsg)
+ sg_unmark_end(dd->in_sgl);
+
+ ret = omap_crypto_align_sg(&tmp, cryptlen,
+ AES_BLOCK_SIZE, &dd->in_sgl[nsg],
+ OMAP_CRYPTO_COPY_DATA |
+ OMAP_CRYPTO_ZERO_BUF |
+ OMAP_CRYPTO_FORCE_SINGLE_ENTRY,
+ FLAGS_IN_DATA_ST_SHIFT,
+ &dd->flags);
+ if (ret)
+ return ret;
+ }
+
+ dd->in_sg = dd->in_sgl;
+ dd->total = cryptlen;
+ dd->assoc_len = assoclen;
+ dd->authsize = authlen;
+
+ dd->out_sg = req->dst;
+ dd->orig_out = req->dst;
+
+ dd->out_sg = scatterwalk_ffwd(sg_arr, req->dst, req->assoclen);
+
+ flags = 0;
+ if (req->src == req->dst || dd->out_sg == sg_arr)
+ flags |= OMAP_CRYPTO_FORCE_COPY;
+
+ if (cryptlen) {
+ ret = omap_crypto_align_sg(&dd->out_sg, cryptlen,
+ AES_BLOCK_SIZE, &dd->out_sgl,
+ flags,
+ FLAGS_OUT_DATA_ST_SHIFT, &dd->flags);
+ if (ret)
+ return ret;
+ }
+
+ dd->in_sg_len = sg_nents_for_len(dd->in_sg, alen + clen);
+ dd->out_sg_len = sg_nents_for_len(dd->out_sg, clen);
+
+ return 0;
+}
+
+static int do_encrypt_iv(struct aead_request *req, u32 *tag, u32 *iv)
+{
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+
+ aes_encrypt(&ctx->actx, (u8 *)tag, (u8 *)iv);
+ return 0;
+}
+
+void omap_aes_gcm_dma_out_callback(void *data)
+{
+ struct omap_aes_dev *dd = data;
+ struct omap_aes_reqctx *rctx;
+ int i, val;
+ u32 *auth_tag, tag[4];
+
+ if (!(dd->flags & FLAGS_ENCRYPT))
+ scatterwalk_map_and_copy(tag, dd->aead_req->src,
+ dd->total + dd->aead_req->assoclen,
+ dd->authsize, 0);
+
+ rctx = aead_request_ctx(dd->aead_req);
+ auth_tag = (u32 *)rctx->auth_tag;
+ for (i = 0; i < 4; i++) {
+ val = omap_aes_read(dd, AES_REG_TAG_N(dd, i));
+ auth_tag[i] = val ^ auth_tag[i];
+ if (!(dd->flags & FLAGS_ENCRYPT))
+ auth_tag[i] = auth_tag[i] ^ tag[i];
+ }
+
+ omap_aes_gcm_done_task(dd);
+}
+
+static int omap_aes_gcm_handle_queue(struct omap_aes_dev *dd,
+ struct aead_request *req)
+{
+ if (req)
+ return crypto_transfer_aead_request_to_engine(dd->engine, req);
+
+ return 0;
+}
+
+static int omap_aes_gcm_prepare_req(struct aead_request *req,
+ struct omap_aes_dev *dd)
+{
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ int err;
+
+ dd->aead_req = req;
+
+ rctx->mode &= FLAGS_MODE_MASK;
+ dd->flags = (dd->flags & ~FLAGS_MODE_MASK) | rctx->mode;
+
+ err = omap_aes_gcm_copy_buffers(dd, req);
+ if (err)
+ return err;
+
+ dd->ctx = &ctx->octx;
+
+ return omap_aes_write_ctrl(dd);
+}
+
+static int omap_aes_gcm_crypt(struct aead_request *req, unsigned long mode)
+{
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ unsigned int authlen = crypto_aead_authsize(aead);
+ struct omap_aes_dev *dd;
+ __be32 counter = cpu_to_be32(1);
+ int err, assoclen;
+
+ memset(rctx->auth_tag, 0, sizeof(rctx->auth_tag));
+ memcpy(rctx->iv + GCM_AES_IV_SIZE, &counter, 4);
+
+ err = do_encrypt_iv(req, (u32 *)rctx->auth_tag, (u32 *)rctx->iv);
+ if (err)
+ return err;
+
+ if (mode & FLAGS_RFC4106_GCM)
+ assoclen = req->assoclen - 8;
+ else
+ assoclen = req->assoclen;
+ if (assoclen + req->cryptlen == 0) {
+ scatterwalk_map_and_copy(rctx->auth_tag, req->dst, 0, authlen,
+ 1);
+ return 0;
+ }
+
+ dd = omap_aes_find_dev(rctx);
+ if (!dd)
+ return -ENODEV;
+ rctx->mode = mode;
+
+ return omap_aes_gcm_handle_queue(dd, req);
+}
+
+int omap_aes_gcm_encrypt(struct aead_request *req)
+{
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+
+ memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
+ return omap_aes_gcm_crypt(req, FLAGS_ENCRYPT | FLAGS_GCM);
+}
+
+int omap_aes_gcm_decrypt(struct aead_request *req)
+{
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+
+ memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
+ return omap_aes_gcm_crypt(req, FLAGS_GCM);
+}
+
+int omap_aes_4106gcm_encrypt(struct aead_request *req)
+{
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+
+ memcpy(rctx->iv, ctx->octx.nonce, 4);
+ memcpy(rctx->iv + 4, req->iv, 8);
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ omap_aes_gcm_crypt(req, FLAGS_ENCRYPT | FLAGS_GCM |
+ FLAGS_RFC4106_GCM);
+}
+
+int omap_aes_4106gcm_decrypt(struct aead_request *req)
+{
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+
+ memcpy(rctx->iv, ctx->octx.nonce, 4);
+ memcpy(rctx->iv + 4, req->iv, 8);
+ return crypto_ipsec_check_assoclen(req->assoclen) ?:
+ omap_aes_gcm_crypt(req, FLAGS_GCM | FLAGS_RFC4106_GCM);
+}
+
+int omap_aes_gcm_setkey(struct crypto_aead *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(tfm);
+ int ret;
+
+ ret = aes_expandkey(&ctx->actx, key, keylen);
+ if (ret)
+ return ret;
+
+ memcpy(ctx->octx.key, key, keylen);
+ ctx->octx.keylen = keylen;
+
+ return 0;
+}
+
+int omap_aes_4106gcm_setkey(struct crypto_aead *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct omap_aes_gcm_ctx *ctx = crypto_aead_ctx(tfm);
+ int ret;
+
+ if (keylen < 4)
+ return -EINVAL;
+ keylen -= 4;
+
+ ret = aes_expandkey(&ctx->actx, key, keylen);
+ if (ret)
+ return ret;
+
+ memcpy(ctx->octx.key, key, keylen);
+ memcpy(ctx->octx.nonce, key + keylen, 4);
+ ctx->octx.keylen = keylen;
+
+ return 0;
+}
+
+int omap_aes_gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
+{
+ return crypto_gcm_check_authsize(authsize);
+}
+
+int omap_aes_4106gcm_setauthsize(struct crypto_aead *parent,
+ unsigned int authsize)
+{
+ return crypto_rfc4106_check_authsize(authsize);
+}
+
+int omap_aes_gcm_crypt_req(struct crypto_engine *engine, void *areq)
+{
+ struct aead_request *req = container_of(areq, struct aead_request,
+ base);
+ struct omap_aes_reqctx *rctx = aead_request_ctx(req);
+ struct omap_aes_dev *dd = rctx->dd;
+ int ret;
+
+ if (!dd)
+ return -ENODEV;
+
+ ret = omap_aes_gcm_prepare_req(req, dd);
+ if (ret)
+ return ret;
+
+ if (dd->in_sg_len)
+ ret = omap_aes_crypt_dma_start(dd);
+ else
+ omap_aes_gcm_dma_out_callback(dd);
+
+ return ret;
+}
+
+int omap_aes_gcm_cra_init(struct crypto_aead *tfm)
+{
+ crypto_aead_set_reqsize(tfm, sizeof(struct omap_aes_reqctx));
+
+ return 0;
+}