s390/zcrypt: enable odd RSA modulus sizes in CRT format

In the past only even modulus sizes were allowed for RSA keys in
CRT format. This restriction was based on limited RSA key generation
on older crypto adapters that provides only even modulus sizes. This
restriction is not valid any more.

Revoke restrictions that crypto requests can be serviced with odd
RSA modulus length in CRT format.
Signed-off-by: NIngo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/crypto/zcrypt_api.c

@@ -472,8 +472,7 @@ static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
 	unsigned long long z1, z2, z3;
 	int rc, copied;
 
-	if (crt->outputdatalength < crt->inputdatalength ||
-	    (crt->inputdatalength & 1))
+	if (crt->outputdatalength < crt->inputdatalength)
 		return -EINVAL;
 	/*
 	 * As long as outputdatalength is big enough, we can set the

drivers/s390/crypto/zcrypt_cca_key.h

@@ -291,7 +291,7 @@ static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt,
 
 	memset(key, 0, sizeof(*key));
 
-	short_len = crt->inputdatalength / 2;
+	short_len = (crt->inputdatalength + 1) / 2;
 	long_len = short_len + 8;
 	pad_len = -(3*long_len + 2*short_len) & 7;
 	key_len = 3*long_len + 2*short_len + pad_len + crt->inputdatalength;

drivers/s390/crypto/zcrypt_msgtype50.c

@@ -248,7 +248,7 @@ static int ICACRT_msg_to_type50CRT_msg(struct zcrypt_device *zdev,
 	unsigned char *p, *q, *dp, *dq, *u, *inp;
 
 	mod_len = crt->inputdatalength;
-	short_len = mod_len / 2;
+	short_len = (mod_len + 1) / 2;
 
 	/*
 	 * CEX2A and CEX3A w/o FW update can handle requests up to

drivers/s390/crypto/zcrypt_pcica.c

@@ -138,7 +138,7 @@ static int ICACRT_msg_to_type4CRT_msg(struct zcrypt_device *zdev,
 	int mod_len, short_len, long_len;
 
 	mod_len = crt->inputdatalength;
-	short_len = mod_len / 2;
+	short_len = (mod_len + 1) / 2;
 	long_len = mod_len / 2 + 8;
 
 	if (mod_len <= 128) {