crypto: caam - add support for RSA algorithm

Add RSA support to caam driver.

Initial author is Yashpal Dutta <yashpal.dutta@freescale.com>.

Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/Kconfig

@@ -99,6 +99,18 @@ config CRYPTO_DEV_FSL_CAAM_AHASH_API
 	  To compile this as a module, choose M here: the module
 	  will be called caamhash.
 
+config CRYPTO_DEV_FSL_CAAM_PKC_API
+        tristate "Register public key cryptography implementations with Crypto API"
+        depends on CRYPTO_DEV_FSL_CAAM && CRYPTO_DEV_FSL_CAAM_JR
+        default y
+        select CRYPTO_RSA
+        help
+          Selecting this will allow SEC Public key support for RSA.
+          Supported cryptographic primitives: encryption, decryption,
+          signature and verification.
+          To compile this as a module, choose M here: the module
+          will be called caam_pkc.
+
 config CRYPTO_DEV_FSL_CAAM_RNG_API
 	tristate "Register caam device for hwrng API"
 	depends on CRYPTO_DEV_FSL_CAAM && CRYPTO_DEV_FSL_CAAM_JR

drivers/crypto/caam/Makefile

@@ -10,6 +10,8 @@ obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_JR) += caam_jr.o
 obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API) += caamalg.o
 obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o
 obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API) += caamrng.o
+obj-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caam_pkc.o
 
 caam-objs := ctrl.o
 caam_jr-objs := jr.o key_gen.o error.o
+caam_pkc-y := caampkc.o pkc_desc.o

drivers/crypto/caam/caampkc.h

@@ -0,0 +1,70 @@
+/*
+ * caam - Freescale FSL CAAM support for Public Key Cryptography descriptors
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
+ * all the desired key parameters, input and output pointers.
+ */
+
+#ifndef _PKC_DESC_H_
+#define _PKC_DESC_H_
+#include "compat.h"
+#include "pdb.h"
+
+/**
+ * caam_rsa_key - CAAM RSA key structure. Keys are allocated in DMA zone.
+ * @n           : RSA modulus raw byte stream
+ * @e           : RSA public exponent raw byte stream
+ * @d           : RSA private exponent raw byte stream
+ * @n_sz        : length in bytes of RSA modulus n
+ * @e_sz        : length in bytes of RSA public exponent
+ * @d_sz        : length in bytes of RSA private exponent
+ */
+struct caam_rsa_key {
+	u8 *n;
+	u8 *e;
+	u8 *d;
+	size_t n_sz;
+	size_t e_sz;
+	size_t d_sz;
+};
+
+/**
+ * caam_rsa_ctx - per session context.
+ * @key         : RSA key in DMA zone
+ * @dev         : device structure
+ */
+struct caam_rsa_ctx {
+	struct caam_rsa_key key;
+	struct device *dev;
+};
+
+/**
+ * rsa_edesc - s/w-extended rsa descriptor
+ * @src_nents     : number of segments in input scatterlist
+ * @dst_nents     : number of segments in output scatterlist
+ * @sec4_sg_bytes : length of h/w link table
+ * @sec4_sg_dma   : dma address of h/w link table
+ * @sec4_sg       : pointer to h/w link table
+ * @pdb           : specific RSA Protocol Data Block (PDB)
+ * @hw_desc       : descriptor followed by link tables if any
+ */
+struct rsa_edesc {
+	int src_nents;
+	int dst_nents;
+	int sec4_sg_bytes;
+	dma_addr_t sec4_sg_dma;
+	struct sec4_sg_entry *sec4_sg;
+	union {
+		struct rsa_pub_pdb pub;
+		struct rsa_priv_f1_pdb priv_f1;
+	} pdb;
+	u32 hw_desc[];
+};
+
+/* Descriptor construction primitives. */
+void init_rsa_pub_desc(u32 *desc, struct rsa_pub_pdb *pdb);
+void init_rsa_priv_f1_desc(u32 *desc, struct rsa_priv_f1_pdb *pdb);
+
+#endif

drivers/crypto/caam/compat.h

@@ -35,8 +35,11 @@
 #include <crypto/md5.h>
 #include <crypto/internal/aead.h>
 #include <crypto/authenc.h>
+#include <crypto/akcipher.h>
 #include <crypto/scatterwalk.h>
 #include <crypto/internal/skcipher.h>
 #include <crypto/internal/hash.h>
+#include <crypto/internal/rsa.h>
+#include <crypto/internal/akcipher.h>
 
 #endif /* !defined(CAAM_COMPAT_H) */

drivers/crypto/caam/desc.h

@@ -453,6 +453,8 @@ struct sec4_sg_entry {
 #define OP_PCLID_PUBLICKEYPAIR	(0x14 << OP_PCLID_SHIFT)
 #define OP_PCLID_DSASIGN	(0x15 << OP_PCLID_SHIFT)
 #define OP_PCLID_DSAVERIFY	(0x16 << OP_PCLID_SHIFT)
+#define OP_PCLID_RSAENC_PUBKEY  (0x18 << OP_PCLID_SHIFT)
+#define OP_PCLID_RSADEC_PRVKEY  (0x19 << OP_PCLID_SHIFT)
 
 /* Assuming OP_TYPE = OP_TYPE_DECAP_PROTOCOL/ENCAP_PROTOCOL */
 #define OP_PCLID_IPSEC		(0x01 << OP_PCLID_SHIFT)

drivers/crypto/caam/desc_constr.h

@@ -77,6 +77,13 @@ static inline void init_job_desc(u32 *desc, u32 options)
 	init_desc(desc, CMD_DESC_HDR | options);
 }
 
+static inline void init_job_desc_pdb(u32 *desc, u32 options, size_t pdb_bytes)
+{
+	u32 pdb_len = (pdb_bytes + CAAM_CMD_SZ - 1) / CAAM_CMD_SZ;
+
+	init_job_desc(desc, (((pdb_len + 1) << HDR_START_IDX_SHIFT)) | options);
+}
+
 static inline void append_ptr(u32 *desc, dma_addr_t ptr)
 {
 	dma_addr_t *offset = (dma_addr_t *)desc_end(desc);

drivers/crypto/caam/pdb.h

@@ -1,12 +1,13 @@
 /*
  * CAAM Protocol Data Block (PDB) definition header file
  *
- * Copyright 2008-2012 Freescale Semiconductor, Inc.
+ * Copyright 2008-2016 Freescale Semiconductor, Inc.
  *
  */
 
 #ifndef CAAM_PDB_H
 #define CAAM_PDB_H
+#include "compat.h"
 
 /*
  * PDB- IPSec ESP Header Modification Options
@@ -476,4 +477,52 @@ struct dsa_verify_pdb {
 	u8 *ab; /* only used if ECC processing */
 };
 
+/* RSA Protocol Data Block */
+#define RSA_PDB_SGF_SHIFT       28
+#define RSA_PDB_E_SHIFT         12
+#define RSA_PDB_E_MASK          (0xFFF << RSA_PDB_E_SHIFT)
+#define RSA_PDB_D_SHIFT         12
+#define RSA_PDB_D_MASK          (0xFFF << RSA_PDB_D_SHIFT)
+
+#define RSA_PDB_SGF_F           (0x8 << RSA_PDB_SGF_SHIFT)
+#define RSA_PDB_SGF_G           (0x4 << RSA_PDB_SGF_SHIFT)
+#define RSA_PRIV_PDB_SGF_F      (0x4 << RSA_PDB_SGF_SHIFT)
+#define RSA_PRIV_PDB_SGF_G      (0x8 << RSA_PDB_SGF_SHIFT)
+
+#define RSA_PRIV_KEY_FRM_1      0
+
+/**
+ * RSA Encrypt Protocol Data Block
+ * @sgf: scatter-gather field
+ * @f_dma: dma address of input data
+ * @g_dma: dma address of encrypted output data
+ * @n_dma: dma address of RSA modulus
+ * @e_dma: dma address of RSA public exponent
+ * @f_len: length in octets of the input data
+ */
+struct rsa_pub_pdb {
+	u32		sgf;
+	dma_addr_t	f_dma;
+	dma_addr_t	g_dma;
+	dma_addr_t	n_dma;
+	dma_addr_t	e_dma;
+	u32		f_len;
+} __packed;
+
+/**
+ * RSA Decrypt PDB - Private Key Form #1
+ * @sgf: scatter-gather field
+ * @g_dma: dma address of encrypted input data
+ * @f_dma: dma address of output data
+ * @n_dma: dma address of RSA modulus
+ * @d_dma: dma address of RSA private exponent
+ */
+struct rsa_priv_f1_pdb {
+	u32		sgf;
+	dma_addr_t	g_dma;
+	dma_addr_t	f_dma;
+	dma_addr_t	n_dma;
+	dma_addr_t	d_dma;
+} __packed;
+
 #endif

drivers/crypto/caam/pkc_desc.c

@@ -0,0 +1,36 @@
+/*
+ * caam - Freescale FSL CAAM support for Public Key Cryptography descriptors
+ *
+ * Copyright 2016 Freescale Semiconductor, Inc.
+ *
+ * There is no Shared Descriptor for PKC so that the Job Descriptor must carry
+ * all the desired key parameters, input and output pointers.
+ */
+#include "caampkc.h"
+#include "desc_constr.h"
+
+/* Descriptor for RSA Public operation */
+void init_rsa_pub_desc(u32 *desc, struct rsa_pub_pdb *pdb)
+{
+	init_job_desc_pdb(desc, 0, sizeof(*pdb));
+	append_cmd(desc, pdb->sgf);
+	append_ptr(desc, pdb->f_dma);
+	append_ptr(desc, pdb->g_dma);
+	append_ptr(desc, pdb->n_dma);
+	append_ptr(desc, pdb->e_dma);
+	append_cmd(desc, pdb->f_len);
+	append_operation(desc, OP_TYPE_UNI_PROTOCOL | OP_PCLID_RSAENC_PUBKEY);
+}
+
+/* Descriptor for RSA Private operation - Private Key Form #1 */
+void init_rsa_priv_f1_desc(u32 *desc, struct rsa_priv_f1_pdb *pdb)
+{
+	init_job_desc_pdb(desc, 0, sizeof(*pdb));
+	append_cmd(desc, pdb->sgf);
+	append_ptr(desc, pdb->g_dma);
+	append_ptr(desc, pdb->f_dma);
+	append_ptr(desc, pdb->n_dma);
+	append_ptr(desc, pdb->d_dma);
+	append_operation(desc, OP_TYPE_UNI_PROTOCOL | OP_PCLID_RSADEC_PRVKEY |
+			 RSA_PRIV_KEY_FRM_1);
+}