#define AES_CT_SIZE_ECB 2
#define AES_CT_SIZE_CBC 3
#define AES_CT_SIZE_CTR 3
+#define AES_CT_SIZE_GCM_OUT 5
+#define AES_CT_SIZE_GCM_IN 6
#define AES_CT_CTRL_HDR cpu_to_le32(0x00220000)
/* AES-CBC/ECB/CTR command token */
#define AES_CMD0 cpu_to_le32(0x05000000)
#define AES_CMD1 cpu_to_le32(0x2d060000)
#define AES_CMD2 cpu_to_le32(0xe4a63806)
+/* AES-GCM command token */
+#define AES_GCM_CMD0 cpu_to_le32(0x0b000000)
+#define AES_GCM_CMD1 cpu_to_le32(0xa0800000)
+#define AES_GCM_CMD2 cpu_to_le32(0x25000010)
+#define AES_GCM_CMD3 cpu_to_le32(0x0f020000)
+#define AES_GCM_CMD4 cpu_to_le32(0x21e60000)
+#define AES_GCM_CMD5 cpu_to_le32(0x40e60000)
+#define AES_GCM_CMD6 cpu_to_le32(0xd0070000)
/* AES transform information word 0 fields */
#define AES_TFM_BASIC_OUT cpu_to_le32(0x4 << 0)
#define AES_TFM_BASIC_IN cpu_to_le32(0x5 << 0)
+#define AES_TFM_GCM_OUT cpu_to_le32(0x6 << 0)
+#define AES_TFM_GCM_IN cpu_to_le32(0xf << 0)
#define AES_TFM_SIZE(x) cpu_to_le32((x) << 8)
#define AES_TFM_128BITS cpu_to_le32(0xb << 16)
#define AES_TFM_192BITS cpu_to_le32(0xd << 16)
/* AES transform information word 1 fields */
#define AES_TFM_ECB cpu_to_le32(0x0 << 0)
#define AES_TFM_CBC cpu_to_le32(0x1 << 0)
+#define AES_TFM_CTR_INIT cpu_to_le32(0x2 << 0) /* init counter to 1 */
#define AES_TFM_CTR_LOAD cpu_to_le32(0x6 << 0) /* load/reuse counter */
+#define AES_TFM_3IV cpu_to_le32(0x7 << 5) /* using IV 0-2 */
#define AES_TFM_FULL_IV cpu_to_le32(0xf << 5) /* using IV 0-3 */
+#define AES_TFM_IV_CTR_MODE cpu_to_le32(0x1 << 10)
+#define AES_TFM_ENC_HASH cpu_to_le32(0x1 << 17)
+#define AES_TFM_GHASH_DIG cpu_to_le32(0x2 << 21)
+#define AES_TFM_GHASH cpu_to_le32(0x4 << 23)
/* AES flags */
#define AES_FLAGS_ECB BIT(0)
#define AES_FLAGS_CBC BIT(1)
#define AES_FLAGS_CTR BIT(2)
-#define AES_FLAGS_ENCRYPT BIT(3)
-#define AES_FLAGS_BUSY BIT(4)
+#define AES_FLAGS_GCM BIT(3)
+#define AES_FLAGS_ENCRYPT BIT(4)
+#define AES_FLAGS_BUSY BIT(5)
/**
* Command token(CT) is a set of hardware instructions that
* - Commands decoding and control of the engine's data path.
* - Coordinating hardware data fetch and store operations.
* - Result token construction and output.
+ *
+ * Memory map of GCM's TFM:
+ * /-----------\
+ * | AES KEY | 128/196/256 bits
+ * |-----------|
+ * | HASH KEY | a string 128 zero bits encrypted using the block cipher
+ * |-----------|
+ * | IVs | 4 * 4 bytes
+ * \-----------/
*/
struct mtk_aes_ct {
- __le32 cmd[AES_CT_SIZE_CBC];
+ __le32 cmd[AES_CT_SIZE_GCM_IN];
};
struct mtk_aes_tfm {
__le32 ctrl[2];
- __le32 state[SIZE_IN_WORDS(AES_KEYSIZE_256 + AES_BLOCK_SIZE)];
+ __le32 state[SIZE_IN_WORDS(AES_KEYSIZE_256 + AES_BLOCK_SIZE * 2)];
};
struct mtk_aes_reqctx {
struct scatterlist dst[2];
};
+struct mtk_aes_gcm_ctx {
+ struct mtk_aes_base_ctx base;
+
+ u32 authsize;
+ size_t textlen;
+
+ struct crypto_skcipher *ctr;
+};
+
+struct mtk_aes_gcm_setkey_result {
+ int err;
+ struct completion completion;
+};
+
struct mtk_aes_drv {
struct list_head dev_list;
/* Device list lock */
}
res->hdr |= MTK_DESC_LAST;
+ /* Prepare enough space for authenticated tag */
+ if (aes->flags & AES_FLAGS_GCM)
+ res->hdr += AES_BLOCK_SIZE;
+
/*
* Make sure that all changes to the DMA ring are done before we
* start engine.
},
};
+static inline struct mtk_aes_gcm_ctx *
+mtk_aes_gcm_ctx_cast(struct mtk_aes_base_ctx *ctx)
+{
+ return container_of(ctx, struct mtk_aes_gcm_ctx, base);
+}
+
+/* Initialize transform information of GCM mode */
+static void mtk_aes_gcm_info_init(struct mtk_cryp *cryp,
+ struct mtk_aes_rec *aes,
+ size_t len)
+{
+ struct aead_request *req = aead_request_cast(aes->areq);
+ struct mtk_aes_base_ctx *ctx = aes->ctx;
+ struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx);
+ const u32 *iv = (const u32 *)req->iv;
+ u32 *iv_state = ctx->tfm.state + ctx->keylen +
+ SIZE_IN_WORDS(AES_BLOCK_SIZE);
+ u32 ivsize = crypto_aead_ivsize(crypto_aead_reqtfm(req));
+ int i;
+
+ ctx->ct_hdr = AES_CT_CTRL_HDR | len;
+
+ ctx->ct.cmd[0] = AES_GCM_CMD0 | cpu_to_le32(req->assoclen);
+ ctx->ct.cmd[1] = AES_GCM_CMD1 | cpu_to_le32(req->assoclen);
+ ctx->ct.cmd[2] = AES_GCM_CMD2;
+ ctx->ct.cmd[3] = AES_GCM_CMD3 | cpu_to_le32(gctx->textlen);
+
+ if (aes->flags & AES_FLAGS_ENCRYPT) {
+ ctx->ct.cmd[4] = AES_GCM_CMD4 | cpu_to_le32(gctx->authsize);
+ ctx->ct_size = AES_CT_SIZE_GCM_OUT;
+ ctx->tfm.ctrl[0] = AES_TFM_GCM_OUT;
+ } else {
+ ctx->ct.cmd[4] = AES_GCM_CMD5 | cpu_to_le32(gctx->authsize);
+ ctx->ct.cmd[5] = AES_GCM_CMD6 | cpu_to_le32(gctx->authsize);
+ ctx->ct_size = AES_CT_SIZE_GCM_IN;
+ ctx->tfm.ctrl[0] = AES_TFM_GCM_IN;
+ }
+
+ if (ctx->keylen == SIZE_IN_WORDS(AES_KEYSIZE_128))
+ ctx->tfm.ctrl[0] |= AES_TFM_128BITS;
+ else if (ctx->keylen == SIZE_IN_WORDS(AES_KEYSIZE_256))
+ ctx->tfm.ctrl[0] |= AES_TFM_256BITS;
+ else
+ ctx->tfm.ctrl[0] |= AES_TFM_192BITS;
+
+ ctx->tfm.ctrl[0] |= AES_TFM_GHASH_DIG | AES_TFM_GHASH |
+ AES_TFM_SIZE(ctx->keylen + SIZE_IN_WORDS(
+ AES_BLOCK_SIZE + ivsize));
+ ctx->tfm.ctrl[1] = AES_TFM_CTR_INIT | AES_TFM_IV_CTR_MODE |
+ AES_TFM_3IV | AES_TFM_ENC_HASH;
+
+ for (i = 0; i < SIZE_IN_WORDS(ivsize); i++)
+ iv_state[i] = cpu_to_le32(iv[i]);
+}
+
+static int mtk_aes_gcm_dma(struct mtk_cryp *cryp, struct mtk_aes_rec *aes,
+ struct scatterlist *src, struct scatterlist *dst,
+ size_t len)
+{
+ bool src_aligned, dst_aligned;
+
+ aes->src.sg = src;
+ aes->dst.sg = dst;
+ aes->real_dst = dst;
+
+ src_aligned = mtk_aes_check_aligned(src, len, &aes->src);
+ if (src == dst)
+ dst_aligned = src_aligned;
+ else
+ dst_aligned = mtk_aes_check_aligned(dst, len, &aes->dst);
+
+ if (!src_aligned || !dst_aligned) {
+ if (aes->total > AES_BUF_SIZE)
+ return -ENOMEM;
+
+ if (!src_aligned) {
+ sg_copy_to_buffer(src, sg_nents(src), aes->buf, len);
+ aes->src.sg = &aes->aligned_sg;
+ aes->src.nents = 1;
+ aes->src.remainder = 0;
+ }
+
+ if (!dst_aligned) {
+ aes->dst.sg = &aes->aligned_sg;
+ aes->dst.nents = 1;
+ aes->dst.remainder = 0;
+ }
+
+ sg_init_table(&aes->aligned_sg, 1);
+ sg_set_buf(&aes->aligned_sg, aes->buf, aes->total);
+ }
+
+ mtk_aes_gcm_info_init(cryp, aes, len);
+
+ return mtk_aes_map(cryp, aes);
+}
+
+/* Todo: GMAC */
+static int mtk_aes_gcm_start(struct mtk_cryp *cryp, struct mtk_aes_rec *aes)
+{
+ struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(aes->ctx);
+ struct aead_request *req = aead_request_cast(aes->areq);
+ struct mtk_aes_reqctx *rctx = aead_request_ctx(req);
+ u32 len = req->assoclen + req->cryptlen;
+
+ mtk_aes_set_mode(aes, rctx);
+
+ if (aes->flags & AES_FLAGS_ENCRYPT) {
+ u32 tag[4];
+ /* Compute total process length. */
+ aes->total = len + gctx->authsize;
+ /* Compute text length. */
+ gctx->textlen = req->cryptlen;
+ /* Hardware will append authenticated tag to output buffer */
+ scatterwalk_map_and_copy(tag, req->dst, len, gctx->authsize, 1);
+ } else {
+ aes->total = len;
+ gctx->textlen = req->cryptlen - gctx->authsize;
+ }
+ aes->resume = mtk_aes_complete;
+
+ return mtk_aes_gcm_dma(cryp, aes, req->src, req->dst, len);
+}
+
+static int mtk_aes_gcm_crypt(struct aead_request *req, u64 mode)
+{
+ struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
+ struct mtk_aes_reqctx *rctx = aead_request_ctx(req);
+
+ rctx->mode = AES_FLAGS_GCM | mode;
+
+ return mtk_aes_handle_queue(ctx->cryp, !!(mode & AES_FLAGS_ENCRYPT),
+ &req->base);
+}
+
+static void mtk_gcm_setkey_done(struct crypto_async_request *req, int err)
+{
+ struct mtk_aes_gcm_setkey_result *result = req->data;
+
+ if (err == -EINPROGRESS)
+ return;
+
+ result->err = err;
+ complete(&result->completion);
+}
+
+/*
+ * Because of the hardware limitation, we need to pre-calculate key(H)
+ * for the GHASH operation. The result of the encryption operation
+ * need to be stored in the transform state buffer.
+ */
+static int mtk_aes_gcm_setkey(struct crypto_aead *aead, const u8 *key,
+ u32 keylen)
+{
+ struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(aead);
+ struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx);
+ struct crypto_skcipher *ctr = gctx->ctr;
+ struct {
+ u32 hash[4];
+ u8 iv[8];
+
+ struct mtk_aes_gcm_setkey_result result;
+
+ struct scatterlist sg[1];
+ struct skcipher_request req;
+ } *data;
+ const u32 *aes_key;
+ u32 *key_state, *hash_state;
+ int err, i;
+
+ if (keylen != AES_KEYSIZE_256 &&
+ keylen != AES_KEYSIZE_192 &&
+ keylen != AES_KEYSIZE_128) {
+ crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+
+ key_state = ctx->tfm.state;
+ aes_key = (u32 *)key;
+ ctx->keylen = SIZE_IN_WORDS(keylen);
+
+ for (i = 0; i < ctx->keylen; i++)
+ ctx->tfm.state[i] = cpu_to_le32(aes_key[i]);
+
+ /* Same as crypto_gcm_setkey() from crypto/gcm.c */
+ crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK);
+ crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) &
+ CRYPTO_TFM_REQ_MASK);
+ err = crypto_skcipher_setkey(ctr, key, keylen);
+ crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) &
+ CRYPTO_TFM_RES_MASK);
+ if (err)
+ return err;
+
+ data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ init_completion(&data->result.completion);
+ sg_init_one(data->sg, &data->hash, AES_BLOCK_SIZE);
+ skcipher_request_set_tfm(&data->req, ctr);
+ skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
+ CRYPTO_TFM_REQ_MAY_BACKLOG,
+ mtk_gcm_setkey_done, &data->result);
+ skcipher_request_set_crypt(&data->req, data->sg, data->sg,
+ AES_BLOCK_SIZE, data->iv);
+
+ err = crypto_skcipher_encrypt(&data->req);
+ if (err == -EINPROGRESS || err == -EBUSY) {
+ err = wait_for_completion_interruptible(
+ &data->result.completion);
+ if (!err)
+ err = data->result.err;
+ }
+ if (err)
+ goto out;
+
+ hash_state = key_state + ctx->keylen;
+
+ for (i = 0; i < 4; i++)
+ hash_state[i] = cpu_to_be32(data->hash[i]);
+out:
+ kzfree(data);
+ return err;
+}
+
+static int mtk_aes_gcm_setauthsize(struct crypto_aead *aead,
+ u32 authsize)
+{
+ struct mtk_aes_base_ctx *ctx = crypto_aead_ctx(aead);
+ struct mtk_aes_gcm_ctx *gctx = mtk_aes_gcm_ctx_cast(ctx);
+
+ /* Same as crypto_gcm_authsize() from crypto/gcm.c */
+ switch (authsize) {
+ case 8:
+ case 12:
+ case 16:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ gctx->authsize = authsize;
+ return 0;
+}
+
+static int mtk_aes_gcm_encrypt(struct aead_request *req)
+{
+ return mtk_aes_gcm_crypt(req, AES_FLAGS_ENCRYPT);
+}
+
+static int mtk_aes_gcm_decrypt(struct aead_request *req)
+{
+ return mtk_aes_gcm_crypt(req, 0);
+}
+
+static int mtk_aes_gcm_init(struct crypto_aead *aead)
+{
+ struct mtk_aes_gcm_ctx *ctx = crypto_aead_ctx(aead);
+ struct mtk_cryp *cryp = NULL;
+
+ cryp = mtk_aes_find_dev(&ctx->base);
+ if (!cryp) {
+ pr_err("can't find crypto device\n");
+ return -ENODEV;
+ }
+
+ ctx->ctr = crypto_alloc_skcipher("ctr(aes)", 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(ctx->ctr)) {
+ pr_err("Error allocating ctr(aes)\n");
+ return PTR_ERR(ctx->ctr);
+ }
+
+ crypto_aead_set_reqsize(aead, sizeof(struct mtk_aes_reqctx));
+ ctx->base.start = mtk_aes_gcm_start;
+ return 0;
+}
+
+static void mtk_aes_gcm_exit(struct crypto_aead *aead)
+{
+ struct mtk_aes_gcm_ctx *ctx = crypto_aead_ctx(aead);
+
+ crypto_free_skcipher(ctx->ctr);
+}
+
+static struct aead_alg aes_gcm_alg = {
+ .setkey = mtk_aes_gcm_setkey,
+ .setauthsize = mtk_aes_gcm_setauthsize,
+ .encrypt = mtk_aes_gcm_encrypt,
+ .decrypt = mtk_aes_gcm_decrypt,
+ .init = mtk_aes_gcm_init,
+ .exit = mtk_aes_gcm_exit,
+ .ivsize = 12,
+ .maxauthsize = AES_BLOCK_SIZE,
+
+ .base = {
+ .cra_name = "gcm(aes)",
+ .cra_driver_name = "gcm-aes-mtk",
+ .cra_priority = 400,
+ .cra_flags = CRYPTO_ALG_ASYNC,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct mtk_aes_gcm_ctx),
+ .cra_alignmask = 0xf,
+ .cra_module = THIS_MODULE,
+ },
+};
+
static void mtk_aes_enc_task(unsigned long data)
{
struct mtk_cryp *cryp = (struct mtk_cryp *)data;
{
int i;
+ crypto_unregister_aead(&aes_gcm_alg);
+
for (i = 0; i < ARRAY_SIZE(aes_algs); i++)
crypto_unregister_alg(&aes_algs[i]);
}
goto err_aes_algs;
}
+ err = crypto_register_aead(&aes_gcm_alg);
+ if (err)
+ goto err_aes_algs;
+
return 0;
err_aes_algs:
projects / kernel.git / commitdiff