Correct typo and improve documentation
diff --git a/include/mbedtls/rsa.h b/include/mbedtls/rsa.h
index bc2f810..54a1f25 100644
--- a/include/mbedtls/rsa.h
+++ b/include/mbedtls/rsa.h
@@ -230,11 +230,11 @@
* \note The input and output buffers must be large
* enough (eg. 128 bytes if RSA-1024 is used).
*
- * \note Blinding is used if and onlf if a PRNG is provided.
+ * \note Blinding is used if and only if a PRNG is provided.
*
* \note If blinding is used, both the base of exponentation
- * and the exponent are blinded, preventing both statistical
- * timing and power analysis attacks.
+ * and the exponent are blinded, providing protection
+ * against some side-channel attacks.
*
* \warning It is deprecated and a security risk to not provide
* a PRNG here and thereby prevent the use of blinding.