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+Compatibility with standards and other software
+==================================================
+
+Python-RSA implements encryption and signatures according to PKCS#1
+version 1.5. This makes it compatible with the OpenSSL RSA module.
+
+Keys are stored in PEM or DER format according to PKCS#1 v1.5. Private
+keys are compatible with OpenSSL. However, OpenSSL uses X.509 for its
+public keys, which are not supported.
+
+:Encryption:
+ PKCS#1 v1.5 with at least 8 bytes of random padding
+
+:Signatures:
+ PKCS#1 v1.5 using the following hash methods:
+ MD5, SHA-1, SHA-256, SHA-384, SHA-512
+
+:Private keys:
+ PKCS#1 v1.5 in PEM and DER format, ASN.1 type RSAPrivateKey
+
+:Public keys:
+ PKCS#1 v1.5 in PEM and DER format, ASN.1 type RSAPublicKey
+
+
+
+Public keys from OpenSSL
+--------------------------------------------------
+
+To get a Python-RSA-compatible public key from OpenSSL, you need the
+private key. Get the private key in PEM or DER format and run it
+through the ``pyrsa-priv2pub`` command::
+
+
+ Usage: pyrsa-priv2pub [options]
+
+ Reads a private key and outputs the corresponding public key. Both
+ private and public keys use the format described in PKCS#1 v1.5
+
+ Options:
+ -h, --help show this help message and exit
+ --in=INFILENAME Input filename. Reads from stdin if not specified
+ --out=OUTFILENAME Output filename. Writes to stdout of not specified
+ --inform=INFORM key format of input - default PEM
+ --outform=OUTFORM key format of output - default PEM