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Chilkat2-Python

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Chilkat Chilkat2-Python Downloads

Chilkat2-Python
import sys
import chilkat2

success = False

# This example assumes the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

pkey = chilkat2.PrivateKey()

# Load the private key from an RSA PEM file:
success = pkey.LoadPemFile("myKey.pem")

rsa = chilkat2.Rsa()

# Import the private key into the RSA component:
success = rsa.UsePrivateKey(pkey)
if (success == False):
    print(rsa.LastErrorText)
    sys.exit()

# OpenSSL uses BigEndian byte ordering:
rsa.LittleEndian = False

# The resulting signature will be a Base64 string:
rsa.EncodingMode = "base64"

# For simplicity, we're not loading
# the data to be signed from a file.  We are instead simply
# using a literal string value.  
strData = "This is the text to be signed."

# Hash the input using MD5, and then sign the hash:
# Other valid hash algorithm choices are "md2" and "sha-1".
base64Sig = rsa.SignStringENC(strData,"md5")

print(base64Sig)

print("Success!")