[PATCH 4/6] crypto: ccp - Add RSA support for a v5 ccp

[Gary R Hook <gary.hook@amd.com>]

Take into account device implementation differences for
RSA.

Signed-off-by: Gary R Hook <gary.hook@amd.com>
---
 drivers/crypto/ccp/ccp-crypto-rsa.c |   14 +++--
 drivers/crypto/ccp/ccp-crypto.h     |    3 -
 drivers/crypto/ccp/ccp-dev.h        |    2 -
 drivers/crypto/ccp/ccp-ops.c        |   97 +++++++++++++++++++++++------------
 4 files changed, 73 insertions(+), 43 deletions(-)

diff --git a/drivers/crypto/ccp/ccp-crypto-rsa.c b/drivers/crypto/ccp/ccp-crypto-rsa.c
index 7dab43b..94411de 100644
--- a/drivers/crypto/ccp/ccp-crypto-rsa.c
+++ b/drivers/crypto/ccp/ccp-crypto-rsa.c
@@ -125,7 +125,7 @@ static void ccp_rsa_free_key_bufs(struct ccp_ctx *ctx)
 }
 
 static int ccp_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
-			  unsigned int keylen, bool public)
+			  unsigned int keylen, bool private)
 {
 	struct ccp_ctx *ctx = akcipher_tfm_ctx(tfm);
 	struct rsa_key raw_key;
@@ -139,10 +139,10 @@ static int ccp_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
 	memset(&raw_key, 0, sizeof(raw_key));
 
 	/* Code borrowed from crypto/rsa.c */
-	if (public)
-		ret = rsa_parse_pub_key(&raw_key, key, keylen);
-	else
+	if (private)
 		ret = rsa_parse_priv_key(&raw_key, key, keylen);
+	else
+		ret = rsa_parse_pub_key(&raw_key, key, keylen);
 	if (ret)
 		goto e_ret;
 
@@ -169,7 +169,7 @@ static int ccp_rsa_setkey(struct crypto_akcipher *tfm, const void *key,
 		goto e_nkey;
 	sg_init_one(&ctx->u.rsa.n_sg, ctx->u.rsa.n_buf, ctx->u.rsa.n_len);
 
-	if (!public) {
+	if (private) {
 		ctx->u.rsa.pkey.d = mpi_read_raw_data(raw_key.d, raw_key.d_sz);
 		if (!ctx->u.rsa.pkey.d)
 			goto e_nkey;
@@ -196,13 +196,13 @@ e_ret:
 static int ccp_rsa_setprivkey(struct crypto_akcipher *tfm, const void *key,
 			      unsigned int keylen)
 {
-	return ccp_rsa_setkey(tfm, key, keylen, false);
+	return ccp_rsa_setkey(tfm, key, keylen, true);
 }
 
 static int ccp_rsa_setpubkey(struct crypto_akcipher *tfm, const void *key,
 			     unsigned int keylen)
 {
-	return ccp_rsa_setkey(tfm, key, keylen, true);
+	return ccp_rsa_setkey(tfm, key, keylen, false);
 }
 
 static int ccp_rsa_init_tfm(struct crypto_akcipher *tfm)
diff --git a/drivers/crypto/ccp/ccp-crypto.h b/drivers/crypto/ccp/ccp-crypto.h
index 4a1d206..c6cf318 100644
--- a/drivers/crypto/ccp/ccp-crypto.h
+++ b/drivers/crypto/ccp/ccp-crypto.h
@@ -138,8 +138,7 @@ struct ccp_aes_cmac_exp_ctx {
 	u8 buf[AES_BLOCK_SIZE];
 };
 
-/*
- * SHA-related defines
+/* SHA-related defines
  * These values must be large enough to accommodate any variant
  */
 #define MAX_SHA_CONTEXT_SIZE	SHA512_DIGEST_SIZE
diff --git a/drivers/crypto/ccp/ccp-dev.h b/drivers/crypto/ccp/ccp-dev.h
index 0d996fe..143f00f 100644
--- a/drivers/crypto/ccp/ccp-dev.h
+++ b/drivers/crypto/ccp/ccp-dev.h
@@ -193,6 +193,7 @@
 #define CCP_SHA_SB_COUNT		1
 
 #define CCP_RSA_MAX_WIDTH		4096
+#define CCP5_RSA_MAX_WIDTH		16384
 
 #define CCP_PASSTHRU_BLOCKSIZE		256
 #define CCP_PASSTHRU_MASKSIZE		32
@@ -515,7 +516,6 @@ struct ccp_op {
 		struct ccp_passthru_op passthru;
 		struct ccp_ecc_op ecc;
 	} u;
-	struct ccp_mem key;
 };
 
 static inline u32 ccp_addr_lo(struct ccp_dma_info *info)
diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index 826782d..07b8dfb 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c
@@ -1283,49 +1283,72 @@ static int ccp_run_rsa_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 	int i = 0;
 	int ret = 0;
 
-	if (rsa->key_size > CCP_RSA_MAX_WIDTH)
-		return -EINVAL;
+	if (cmd_q->ccp->vdata->version < CCP_VERSION(4, 0)) {
+		if (rsa->key_size > CCP_RSA_MAX_WIDTH)
+			return -EINVAL;
+	} else {
+		if (rsa->key_size > CCP5_RSA_MAX_WIDTH)
+			return -EINVAL;
+	}
 
 	if (!rsa->exp || !rsa->mod || !rsa->src || !rsa->dst)
 		return -EINVAL;
 
-	/* The RSA modulus must precede the message being acted upon, so
-	 * it must be copied to a DMA area where the message and the
-	 * modulus can be concatenated.  Therefore the input buffer
-	 * length required is twice the output buffer length (which
-	 * must be a multiple of 256-bits).
-	 */
-	o_len = ((rsa->key_size + 255) / 256) * 32;
-	i_len = o_len * 2;
-
-	sb_count = o_len / CCP_SB_BYTES;
-
 	memset(&op, 0, sizeof(op));
 	op.cmd_q = cmd_q;
-	op.jobid = ccp_gen_jobid(cmd_q->ccp);
-	op.sb_key = cmd_q->ccp->vdata->perform->sballoc(cmd_q, sb_count);
+	op.jobid = CCP_NEW_JOBID(cmd_q->ccp);
 
-	if (!op.sb_key)
-		return -EIO;
+	if (cmd_q->ccp->vdata->version < CCP_VERSION(4, 0)) {
+		/* The RSA modulus must precede the message being acted upon, so
+		 * it must be copied to a DMA area where the message and the
+		 * modulus can be concatenated.  Therefore the input buffer
+		 * length required is twice the output buffer length (which
+		 * must be a multiple of 256-bits).
+		 */
+		sb_count = (rsa->key_size + CCP_SB_BYTES - 1) / CCP_SB_BYTES;
+		o_len = sb_count * 32; /* bytes */
+		i_len = o_len * 2; /* bytes */
+
+		op.sb_key = cmd_q->ccp->vdata->perform->sballoc(cmd_q,
+								sb_count);
+		if (!op.sb_key)
+			return -EIO;
+	} else {
+		/* A version 5 device allows the key to be in memory */
+		o_len = rsa->mod_len;
+		i_len = o_len * 2; /* bytes */
+		op.sb_key = cmd_q->sb_key;
+	}
 
-	/* The RSA exponent may span multiple (32-byte) SB entries and must
-	 * be in little endian format. Reverse copy each 32-byte chunk
-	 * of the exponent (En chunk to E0 chunk, E(n-1) chunk to E1 chunk)
-	 * and each byte within that chunk and do not perform any byte swap
-	 * operations on the passthru operation.
-	 */
 	ret = ccp_init_dm_workarea(&exp, cmd_q, o_len, DMA_TO_DEVICE);
 	if (ret)
 		goto e_sb;
 
-	ret = ccp_reverse_set_dm_area(&exp, 0, rsa->exp, 0, rsa->exp_len);
+	if (rsa->mode == CCP_RSA_ENCRYPT)
+		ret = ccp_reverse_set_dm_area(&exp, 0, rsa->exp, 0,
+					      rsa->exp_len);
+	else
+		ret = ccp_reverse_set_dm_area(&exp, 0, rsa->d_sg, 0,
+					      rsa->d_len);
 	if (ret)
 		goto e_exp;
-	ret = ccp_copy_to_sb(cmd_q, &exp, op.jobid, op.sb_key,
-			     CCP_PASSTHRU_BYTESWAP_NOOP);
-	if (ret) {
-		cmd->engine_error = cmd_q->cmd_error;
-		goto e_exp;
+
+	if (cmd_q->ccp->vdata->version < CCP_VERSION(4, 0)) {
+		/* The RSA exponent may span multiple (32-byte) KSB entries and
+		 * must be in little endian format. Reverse copy each 32-byte
+		 * chunk of the exponent (En chunk to E0 chunk, E(n-1) chunk to
+		 * E1 chunk) and each byte within that chunk and do not perform
+		 * any byte swap operations on the passthru operation.
+		 */
+		ret = ccp_copy_to_sb(cmd_q, &exp, op.jobid, op.sb_key,
+				     CCP_PASSTHRU_BYTESWAP_NOOP);
+		if (ret) {
+			cmd->engine_error = cmd_q->cmd_error;
+			goto e_exp;
+		}
+	} else {
+		op.exp.u.dma.address = exp.dma.address;
+		op.exp.u.dma.offset = 0;
 	}
 
 	/* Concatenate the modulus and the message. Both the modulus and
@@ -1345,7 +1368,7 @@ static int ccp_run_rsa_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 	src.address -= o_len;	/* Reset the address to original value */
 
 	/* Prepare the output area for the operation */
-	ret = ccp_init_data(&dst, cmd_q, rsa->dst, rsa->mod_len,
+	ret = ccp_init_data(&dst, cmd_q, rsa->dst, rsa->dst_len,
 			    o_len, DMA_FROM_DEVICE);
 	if (ret)
 		goto e_src;
@@ -1358,7 +1381,10 @@ static int ccp_run_rsa_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 	op.dst.u.dma.offset = 0;
 	op.dst.u.dma.length = o_len;
 
-	op.u.rsa.mod_size = rsa->key_size;
+	if (cmd_q->ccp->vdata->version < CCP_VERSION(4, 0))
+		op.u.rsa.mod_size = rsa->key_size * 8; /* In bits */
+	else
+		op.u.rsa.mod_size = rsa->key_size;
 	op.u.rsa.input_len = i_len;
 
 	ret = cmd_q->ccp->vdata->perform->rsa(&op);
@@ -1366,8 +1392,12 @@ static int ccp_run_rsa_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
 		cmd->engine_error = cmd_q->cmd_error;
 		goto e_dst;
 	}
+	/* Return the length of the result, too */
+	for (i = o_len; !dst.dm_wa.address[--i]; )
+		;
+	rsa->d_len = i + 1;
 
-	ccp_reverse_get_dm_area(&dst.dm_wa, 0, rsa->dst, 0, rsa->mod_len);
+	ccp_reverse_get_dm_area(&dst.dm_wa, 0, rsa->dst, 0, rsa->d_len);
 
 e_dst:
 	ccp_free_data(&dst, cmd_q);
@@ -1379,7 +1409,8 @@ e_exp:
 	ccp_dm_free(&exp);
 
 e_sb:
-	cmd_q->ccp->vdata->perform->sbfree(cmd_q, op.sb_key, sb_count);
+	if (cmd_q->ccp->vdata->version < CCP_VERSION(4, 0))
+		cmd_q->ccp->vdata->perform->sbfree(cmd_q, op.sb_key, sb_count);
 
 	return ret;
 }