Tcl

PKCS11 Find Certificate with Key Usage on Smart Card or USB Token

See more PKCS11 Examples

Demonstrates how to find and return the 1st certificate on a smart card or USB token with a desired intended key usage.

Note: This example requires Chilkat v9.5.0.91 or later.

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.

# Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

set pkcs11 [new_CkPkcs11]

CkPkcs11_put_SharedLibPath $pkcs11 "aetpkss1.dll"

set success [CkPkcs11_Initialize $pkcs11]
if {$success == 0} then {
    puts [CkPkcs11_lastErrorText $pkcs11]
    delete_CkPkcs11 $pkcs11
    exit
}

# Pass -1 for the slotID to open a session on the first non-empty slot.
set slotID -1

# Open a session.
set readWrite 1
set success [CkPkcs11_OpenSession $pkcs11 $slotID $readWrite]
if {$success == 0} then {
    puts [CkPkcs11_lastErrorText $pkcs11]
    delete_CkPkcs11 $pkcs11
    exit
}

# Make it an authenticated session by calling Login.
# 
# If we don't authenticate, then we won't be able to see the private keys, and thus
# we won't know which certificates have an associated private key stored on the smart card.

# The smart card PIN is passed to the Login method.
# userType 1 indicates a "Normal User".
set userType 1
set pin "0000"
set success [CkPkcs11_Login $pkcs11 $userType $pin]
if {$success == 0} then {
    puts [CkPkcs11_lastErrorText $pkcs11]
    set success [CkPkcs11_CloseSession $pkcs11]
    delete_CkPkcs11 $pkcs11
    exit
}

# --------------------------------------------------------------------------

set cert [new_CkCert]

# Find a certificate with an intended key usage.
# Possible key usages to find are:
# 
# DigitalSignature
# NonRepudiation
# KeyEncipherment
# DataEncipherment
# CertificateSigning
# CrlSigning
# 
# To find a cert having any one of several usages, pass a comma-separated list of usages:
set success [CkPkcs11_FindCert $pkcs11 "keyUsage" "NonRepudiation,DigitalSignature" $cert]
if {$success == 1} then {
    puts "Cert with private key: [CkCert_subjectCN $cert]"
} else {
    puts "No certificates having the intended key usage were found."
}

# --------------------------------------------------------------------------

# Revert to an unauthenticated session by calling Logout.
set success [CkPkcs11_Logout $pkcs11]
if {$success == 0} then {
    puts [CkPkcs11_lastErrorText $pkcs11]
    set success [CkPkcs11_CloseSession $pkcs11]
    delete_CkPkcs11 $pkcs11
    delete_CkCert $cert
    exit
}

# When finished, close the session.
# It is important to close the session (memory leaks will occur if the session is not properly closed).
set success [CkPkcs11_CloseSession $pkcs11]
if {$success == 0} then {
    puts [CkPkcs11_lastErrorText $pkcs11]
    delete_CkPkcs11 $pkcs11
    delete_CkCert $cert
    exit
}

puts "Success."

delete_CkPkcs11 $pkcs11
delete_CkCert $cert