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, 33 insertions, 0 deletions

diff --git a/drivers/crypto/caam/pdb.h b/drivers/crypto/caam/pdb.h
index 8ea5e612927e..31e59963f4d2 100644
--- a/drivers/crypto/caam/pdb.h
+++ b/drivers/crypto/caam/pdb.h
@@ -493,6 +493,7 @@ struct dsa_verify_pdb {
 
 #define RSA_PRIV_KEY_FRM_1      0
 #define RSA_PRIV_KEY_FRM_2      1
+#define RSA_PRIV_KEY_FRM_3      2
 
 /**
  * RSA Encrypt Protocol Data Block
@@ -554,4 +555,36 @@ struct rsa_priv_f2_pdb {
 	u32		p_q_len;
 } __packed;
 
+/**
+ * RSA Decrypt PDB - Private Key Form #3
+ * This is the RSA Chinese Reminder Theorem (CRT) form for two prime factors of
+ * the RSA modulus.
+ * @sgf     : scatter-gather field
+ * @g_dma   : dma address of encrypted input data
+ * @f_dma   : dma address of output data
+ * @c_dma   : dma address of RSA CRT coefficient
+ * @p_dma   : dma address of RSA prime factor p of RSA modulus n
+ * @q_dma   : dma address of RSA prime factor q of RSA modulus n
+ * @dp_dma  : dma address of RSA CRT exponent of RSA prime factor p
+ * @dp_dma  : dma address of RSA CRT exponent of RSA prime factor q
+ * @tmp1_dma: dma address of temporary buffer. CAAM uses this temporary buffer
+ *            as internal state buffer. It is assumed to be as long as p.
+ * @tmp2_dma: dma address of temporary buffer. CAAM uses this temporary buffer
+ *            as internal state buffer. It is assumed to be as long as q.
+ * @p_q_len : length in bytes of first two prime factors of the RSA modulus n
+ */
+struct rsa_priv_f3_pdb {
+	u32		sgf;
+	dma_addr_t	g_dma;
+	dma_addr_t	f_dma;
+	dma_addr_t	c_dma;
+	dma_addr_t	p_dma;
+	dma_addr_t	q_dma;
+	dma_addr_t	dp_dma;
+	dma_addr_t	dq_dma;
+	dma_addr_t	tmp1_dma;
+	dma_addr_t	tmp2_dma;
+	u32		p_q_len;
+} __packed;
+
 #endif