Tcl

Combine Timestamp Reply and Content File into a TimeStampData

See more ASN.1 Examples

Demonstrates how to combine a timestamp reply (RFC 3161) with a data file (any type of file) to create a TimeStampData structure (RFC 5544). 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.

# Also see this example:
# Send a TimeStamp Request to a TimeStamp Authority and get the Response

# Load a timestamp reply file
set bdTsr [new_CkBinData]

set success [CkBinData_LoadFile $bdTsr "qa_data/tsd/sample.tsr"]
if {$success != 1} then {
    puts "Failed to load timestamp reply file."
    delete_CkBinData $bdTsr
    exit
}

# Load the tsr into an ASN.1 object.
set asnTsr [new_CkAsn]

set success [CkAsn_LoadEncoded $asnTsr [CkBinData_getEncoded $bdTsr "base64"] "base64"]
if {$success != 1} then {
    puts [CkAsn_lastErrorText $asnTsr]
    delete_CkBinData $bdTsr
    delete_CkAsn $asnTsr
    exit
}

# Get the timestamp reply as XML.
set xmlTsr [new_CkXml]

CkXml_LoadXml $xmlTsr [CkAsn_asnToXml $asnTsr]

# The timestamp reply XML begins like this:
# We'll want to remove the 1st "sequence" subtree.

#     <?xml version="1.0" encoding="utf-8"?>
#     <sequence>
#         <sequence>       <---- Remove this sub-tree.
#             <int>00</int>
#             <sequence>
#                 <utf8>Operation Okay</utf8>
#             </sequence>
#         </sequence>
#         <sequence>   
#             <oid>1.2.840.113549.1.7.2</oid>
#             <contextSpecific tag="0" constructed="1">
#             ...

# Remove the 1st sub-tree..
CkXml_RemoveChildByIndex $xmlTsr 0

# In this example, the data file we're combining with the timestamp into a timestampData is a .p7m.
# However, it can be any type of file (text or binary), it doesn't matter..
set bdContent [new_CkBinData]

set success [CkBinData_LoadFile $bdContent "qa_data/tsd/sample.p7m"]
if {$success != 1} then {
    puts "Failed to load content file."
    delete_CkBinData $bdTsr
    delete_CkAsn $asnTsr
    delete_CkXml $xmlTsr
    delete_CkBinData $bdContent
    exit
}

# Begin building the TimeStampData.  
# We'll build as XML and then convert to ASN.1
set xml [new_CkXml]

CkXml_put_Tag $xml "sequence"
CkXml_UpdateChildContent $xml "oid" "1.2.840.113549.1.9.16.1.31"
CkXml_UpdateAttrAt $xml "contextSpecific" 1 "tag" "0"
CkXml_UpdateAttrAt $xml "contextSpecific" 1 "constructed" "1"
CkXml_UpdateChildContent $xml "contextSpecific|sequence|int" "01"
CkXml_UpdateChildContent $xml "contextSpecific|sequence|octets" [CkBinData_getEncoded $bdContent "base64"]
CkXml_UpdateAttrAt $xml "contextSpecific|sequence|contextSpecific" 1 "tag" "0"
CkXml_UpdateAttrAt $xml "contextSpecific|sequence|contextSpecific" 1 "constructed" "1"

# xContext is a CkXml
set xContext [CkXml_GetChildWithTag $xml "contextSpecific|sequence|contextSpecific"]
CkXml_AddChildTree $xContext $xmlTsr
delete_CkXml $xContext

# Convert the XML to ASN.1
set tsd [new_CkAsn]

CkAsn_LoadAsnXml $tsd [CkXml_getXml $xml]

# Write the timestamped data to a file.
set success [CkAsn_WriteBinaryDer $tsd "qa_output/sample.tsd"]

# Alternatively, get the tsd ASN.1 as base64..
set tsdBase64 [CkAsn_getEncodedDer $tsd "base64_mime"]
puts "$tsdBase64"

delete_CkBinData $bdTsr
delete_CkAsn $asnTsr
delete_CkXml $xmlTsr
delete_CkBinData $bdContent
delete_CkXml $xml
delete_CkAsn $tsd