Tcl

Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

See more OpenSSL Examples

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

The in.dat file can contain text or binary data of any type. The OpenSSL command does the following:

1. Creates a SHA256 digest of the contents of the input file
2. Signs the SHA256 digest using the private key.

Tcl

load ./chilkat.dll

set success 0

# This example requires 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 PEM file:
set success [CkPrivateKey_LoadPemFile $pkey "private.pem"]
if {$success == 0} then {
    puts [CkPrivateKey_lastErrorText $pkey]
    delete_CkPrivateKey $pkey
    exit
}

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 big-endian.
CkRsa_put_LittleEndian $rsa 0

# Load the file to be signed.
set bdFileData [new_CkBinData]

set success [CkBinData_LoadFile $bdFileData "in.dat"]

set bdSig [new_CkBinData]

set success [CkRsa_SignBd $rsa $bdFileData "sha256" $bdSig]
if {$success == 0} then {
    puts [CkRsa_lastErrorText $rsa]
    delete_CkPrivateKey $pkey
    delete_CkRsa $rsa
    delete_CkBinData $bdFileData
    delete_CkBinData $bdSig
    exit
}

# Save the binary signature to a file.
set success [CkBinData_WriteFile $bdSig "signature.sig"]
if {$success != 1} then {
    puts "Failed to write signature.sig."
    delete_CkPrivateKey $pkey
    delete_CkRsa $rsa
    delete_CkBinData $bdFileData
    delete_CkBinData $bdSig
    exit
}

puts "Success."

delete_CkPrivateKey $pkey
delete_CkRsa $rsa
delete_CkBinData $bdFileData
delete_CkBinData $bdSig