crypto: caam - add support for RSA key form 3

CAAM RSA private key may have either of three representations.

1. The first representation consists of the pair (n, d), where the
   components have the following meanings:
      n      the RSA modulus
      d      the RSA private exponent

2. The second representation consists of the triplet (p, q, d), where
the
   components have the following meanings:
      p      the first prime factor of the RSA modulus n
      q      the second prime factor of the RSA modulus n
      d      the RSA private exponent

3. The third representation consists of the quintuple (p, q, dP, dQ,
qInv),
   where the components have the following meanings:
      p      the first prime factor of the RSA modulus n
      q      the second prime factor of the RSA modulus n
      dP     the first factors's CRT exponent
      dQ     the second factors's CRT exponent
      qInv   the (first) CRT coefficient

The benefit of using the third or the second key form is lower
computational cost for the decryption and signature operations.

This patch adds support for the third RSA private key
representations and extends caampkc to use the fastest key when all
related components are present in the private key.

Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Radu Alexe <radu.alexe@nxp.com>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 21 insertions, 1 deletions

diff --git a/drivers/crypto/caam/caampkc.h b/drivers/crypto/caam/caampkc.h
index 48e408ceaf75..87ab75e9df43 100644
--- a/drivers/crypto/caam/caampkc.h
+++ b/drivers/crypto/caam/caampkc.h
@@ -14,7 +14,7 @@
 
 /**
  * caam_priv_key_form - CAAM RSA private key representation
- * CAAM RSA private key may have either of two forms.
+ * CAAM RSA private key may have either of three forms.
  *
  * 1. The first representation consists of the pair (n, d), where the
  *    components have the following meanings:
@@ -26,10 +26,22 @@
  *        p      the first prime factor of the RSA modulus n
  *        q      the second prime factor of the RSA modulus n
  *        d      the RSA private exponent
+ *
+ * 3. The third representation consists of the quintuple (p, q, dP, dQ, qInv),
+ *    where the components have the following meanings:
+ *        p      the first prime factor of the RSA modulus n
+ *        q      the second prime factor of the RSA modulus n
+ *        dP     the first factors's CRT exponent
+ *        dQ     the second factors's CRT exponent
+ *        qInv   the (first) CRT coefficient
+ *
+ * The benefit of using the third or the second key form is lower computational
+ * cost for the decryption and signature operations.
  */
 enum caam_priv_key_form {
 	FORM1,
 	FORM2,
+	FORM3
 };
 
 /**
@@ -39,6 +51,9 @@ enum caam_priv_key_form {
  * @d           : RSA private exponent raw byte stream
  * @p           : RSA prime factor p of RSA modulus n
  * @q           : RSA prime factor q of RSA modulus n
+ * @dp          : RSA CRT exponent of p
+ * @dp          : RSA CRT exponent of q
+ * @qinv        : RSA CRT coefficient
  * @tmp1        : CAAM uses this temporary buffer as internal state buffer.
  *                It is assumed to be as long as p.
  * @tmp2        : CAAM uses this temporary buffer as internal state buffer.
@@ -56,6 +71,9 @@ struct caam_rsa_key {
 	u8 *d;
 	u8 *p;
 	u8 *q;
+	u8 *dp;
+	u8 *dq;
+	u8 *qinv;
 	u8 *tmp1;
 	u8 *tmp2;
 	size_t n_sz;
@@ -96,6 +114,7 @@ struct rsa_edesc {
 		struct rsa_pub_pdb pub;
 		struct rsa_priv_f1_pdb priv_f1;
 		struct rsa_priv_f2_pdb priv_f2;
+		struct rsa_priv_f3_pdb priv_f3;
 	} pdb;
 	u32 hw_desc[];
 };
@@ -104,5 +123,6 @@ struct rsa_edesc {
 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);
 void init_rsa_priv_f2_desc(u32 *desc, struct rsa_priv_f2_pdb *pdb);
+void init_rsa_priv_f3_desc(u32 *desc, struct rsa_priv_f3_pdb *pdb);
 
 #endif