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Tcl

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 Tcl Downloads

Tcl

load ./chilkat.dll

set success 0

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

set pkey [new_CkPrivateKey]

# Load the private key from an RSA PEM file:
set success [CkPrivateKey_LoadPemFile $pkey "myKey.pem"]

set rsa [new_CkRsa]

# Import the private key into the RSA component:
set success [CkRsa_UsePrivateKey $rsa $pkey]
if {$success == 0} then {
    puts [CkRsa_lastErrorText $rsa]
    delete_CkPrivateKey $pkey
    delete_CkRsa $rsa
    exit
}

# OpenSSL uses BigEndian byte ordering:
CkRsa_put_LittleEndian $rsa 0

# The resulting signature will be a Base64 string:
CkRsa_put_EncodingMode $rsa "base64"

# For simplicity, we're not loading
# the data to be signed from a file.  We are instead simply
# using a literal string value.  
set 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".
set base64Sig [CkRsa_signStringENC $rsa $strData "md5"]

puts "$base64Sig"

puts "Success!"

delete_CkPrivateKey $pkey
delete_CkRsa $rsa