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Tcl

Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

See more OpenSSL Examples

How to create a PKCS12 (.p12 or .pfx) from a certificate file and private key file: Demonstrates how to duplicate this OpenSSL command:
Duplicate openssl pkcs12 –export –in certfile.cer –inkey certfile.key –out certfile.pfx

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 the file.
set success [CkPrivateKey_LoadAnyFormatFile $pkey "certFile.key" ""]
if {$success != 1} then {
    puts [CkPrivateKey_lastErrorText $pkey]
    delete_CkPrivateKey $pkey
    exit
}

set cert [new_CkCert]

# The LoadFromFile method auto-recognizes the format...
set success [CkCert_LoadFromFile $cert "certfile.cer"]
if {$success != 1} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkPrivateKey $pkey
    delete_CkCert $cert
    exit
}

# We'll need a cert chain object to create the PKCS12, so get it
# from the cert.  
# certChain is a CkCertChain

set certChain [CkCert_GetCertChain $cert]
if {![CkCert_get_LastMethodSuccess $cert]} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkPrivateKey $pkey
    delete_CkCert $cert
    exit
}

# Create the PFX object, add the cert and private key, and write to a .pfx file.
set pfx [new_CkPfx]

# The cert(s) are automatically added in the call to AddPrivateKey
set success [CkPfx_AddPrivateKey $pfx $pkey $certChain]
if {$success != 1} then {
    puts [CkPfx_lastErrorText $pfx]
    delete_CkPrivateKey $pkey
    delete_CkCert $cert
    delete_CkPfx $pfx
    exit
}

# Write the .pfx to a file.
set password "myPassword"
set success [CkPfx_ToFile $pfx $password "certfile.pfx"]
if {$success != 1} then {
    puts [CkPfx_lastErrorText $pfx]
    delete_CkPrivateKey $pkey
    delete_CkCert $cert
    delete_CkPfx $pfx
    exit
}

puts "Success."

delete_CkPrivateKey $pkey
delete_CkCert $cert
delete_CkPfx $pfx