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Tcl

Create PKCS1 RSA Signature with PEM Private Key

See more RSA Examples

Demonstrates how to load a private key from a PEM file and create a PKCS1 RSA digital signature.

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 $pkey "pvkey2_rsa.pem"]
if {$success == 0} then {
    puts [CkPrivateKey_lastErrorText $pkey]
    delete_CkPrivateKey $pkey
    exit
}

set rsa [new_CkRsa]

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

# Get the signature as hex.
CkRsa_put_EncodingMode $rsa "hex"

set strData "This is the string to be signed."

# Sign the string using the sha-1 hash algorithm.
# Other valid choices are "md2", "md5", "sha256",
# "sha384", and "sha512".
set hexSig [CkRsa_signStringENC $rsa $strData "sha-1"]

puts "$hexSig"

puts "Success!"

delete_CkPrivateKey $pkey
delete_CkRsa $rsa