(Tcl) Sign a Byte Array to Create a Detached Signature in a Byte Array

Signs data contained in a byte array to produce a detached signature (also in a byte array). Also shows how to verify the signature.

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load ./chilkat.dll

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

set cert [new_CkCert]

set success [CkCert_LoadPfxFile $cert "qa_data/pfx/cert_test123.pfx" "test123"]
if {$success == 0} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkCert $cert
    exit
}

set fac [new_CkFileAccess]

set fileBytes [new_CkByteData]

set success [CkFileAccess_ReadEntireFile $fac "qa_data/pdf/sample.pdf" $fileBytes]
if {[CkFileAccess_get_LastMethodSuccess $fac] != 1} then {
    puts [CkFileAccess_lastErrorText $fac]
    delete_CkCert $cert
    delete_CkFileAccess $fac
    delete_CkByteData $fileBytes
    exit
}

set crypt [new_CkCrypt2]

set success [CkCrypt2_SetSigningCert $crypt $cert]

# We can sign any type of file.
# The result is a detached signature (a signature that does not contain the data being signed).

set sigBytes [new_CkByteData]

set success [CkCrypt2_SignBytes $crypt $fileBytes $sigBytes]
if {[CkCrypt2_get_LastMethodSuccess $crypt] != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkCert $cert
    delete_CkFileAccess $fac
    delete_CkByteData $fileBytes
    delete_CkCrypt2 $crypt
    delete_CkByteData $sigBytes
    exit
}

set success [CkFileAccess_WriteEntireFile $fac "qa_output/sample.pdf.p7s" $sigBytes]
if {[CkFileAccess_get_LastMethodSuccess $fac] != 1} then {
    puts [CkFileAccess_lastErrorText $fac]
    delete_CkCert $cert
    delete_CkFileAccess $fac
    delete_CkByteData $fileBytes
    delete_CkCrypt2 $crypt
    delete_CkByteData $sigBytes
    exit
}

# We can verify the detached signature like this
set verified [CkCrypt2_VerifyBytes $crypt $fileBytes $sigBytes]
if {[CkCrypt2_get_LastMethodSuccess $crypt] != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkCert $cert
    delete_CkFileAccess $fac
    delete_CkByteData $fileBytes
    delete_CkCrypt2 $crypt
    delete_CkByteData $sigBytes
    exit
}

puts "Verified = $verified"

delete_CkCert $cert
delete_CkFileAccess $fac
delete_CkByteData $fileBytes
delete_CkCrypt2 $crypt
delete_CkByteData $sigBytes