(Tcl) Sign String to create a CAdES-T Signature, using HTTP Proxy to Access Timestamp Server

This example will sign a string to create a CAdEST-T signature. It will use an HTTP proxy to access the timestamp server.

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load ./chilkat.dll

set crypt [new_CkCrypt2]

set cert [new_CkCert]

CkCert_put_SmartCardPin $cert "123456"
set success [CkCert_LoadFromSmartcard $cert ""]
if {$success != 1} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    exit
}

set success [CkCrypt2_SetSigningCert $crypt $cert]

# Use SHA-256 rather than the default of SHA-1
CkCrypt2_put_HashAlgorithm $crypt "sha256"

# Create JSON that tells Chilkat what signing attributes to include:
set attrs [new_CkJsonObject]

CkJsonObject_UpdateBool $attrs "contentType" 1
CkJsonObject_UpdateBool $attrs "signingTime" 1
CkJsonObject_UpdateBool $attrs "messageDigest" 1
CkJsonObject_UpdateBool $attrs "signingCertificateV2" 1

# A CAdES-T signature is one that includes a timestampToken created by an online TSA (time stamping authority).
# We must include the TSA's URL, as well as a few options to indicate what is desired.
# Except for the TSA URL, the options shown here are typically what you would need.
CkJsonObject_UpdateBool $attrs "timestampToken.enabled" 1
CkJsonObject_UpdateString $attrs "timestampToken.tsaUrl" "https://freetsa.org/tsr"
CkJsonObject_UpdateBool $attrs "timestampToken.addNonce" 0
CkJsonObject_UpdateBool $attrs "timestampToken.requestTsaCert" 1
CkJsonObject_UpdateString $attrs "timestampToken.hashAlg" "sha256"

CkCrypt2_put_SigningAttributes $crypt [CkJsonObject_emit $attrs]

set strToSign "Hello World!"

set bd [new_CkBinData]

CkBinData_AppendString $bd $strToSign "utf-8"

# -------------------------------------------------------------------------
# The purpose of this example is to show how an HTTP object with custom
# settings can be used to access the Internet when signing.
# Access to the Internet is needed to communicate with the timestamp server.
set http [new_CkHttp]

# This can be a domain name, hostname, or IP address.
CkHttp_put_ProxyDomain $http "172.16.16.56"
CkHttp_put_ProxyPort $http 808
CkHttp_put_ProxyLogin $http "myProxyLogin"
CkHttp_put_ProxyPassword $http "myProxyPassword"
CkCrypt2_SetTsaHttpObj $crypt $http
# -------------------------------------------------------------------------

# This creates the CAdES-T signature.  During the signature creation, it
# communicates with the TSA to get a timestampToken.
# The contents of bd are signed and replaced with the CAdES-T signature (which embeds the original content).
set success [CkCrypt2_OpaqueSignBd $crypt $bd]
if {$success != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    delete_CkJsonObject $attrs
    delete_CkBinData $bd
    delete_CkHttp $http
    exit
}

# Get the signature in base64 format:
puts [CkBinData_getEncoded $bd base64_mime]

puts "Success."

delete_CkCrypt2 $crypt
delete_CkCert $cert
delete_CkJsonObject $attrs
delete_CkBinData $bd
delete_CkHttp $http