Tcl
Tcl
Create a JWS into a StringBuilder
See more JSON Web Signatures (JWS) Examples
Demonstrates Jws.CreateJwsSb, which creates a JWS and writes it into a StringBuilder.
Background. JWS (JSON Web Signature) integrity-protects a payload with a signature or MAC. The header
alg names the algorithm; this example uses HMAC-SHA256 (HS256) with a symmetric MAC key.Chilkat Tcl Downloads
load ./chilkat.dll
set success 0
set jws [new_CkJws]
# Set the protected header for signer 0, specifying the signature algorithm (alg).
set header [new_CkJsonObject]
CkJsonObject_UpdateString $header "alg" "HS256"
set success [CkJws_SetProtectedHeader $jws 0 $header]
if {$success == 0} then {
puts [CkJws_lastErrorText $jws]
delete_CkJws $jws
delete_CkJsonObject $header
exit
}
# Set the payload to be signed.
set bIncludeBom 0
set success [CkJws_SetPayload $jws "This is the content to sign." "utf-8" $bIncludeBom]
if {$success == 0} then {
puts [CkJws_lastErrorText $jws]
delete_CkJws $jws
delete_CkJsonObject $header
exit
}
# Provide the HMAC key (base64) for signer 0. In production, obtain the key from a secure source
# rather than hard-coding it.
set base64Key "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
set success [CkJws_SetMacKey $jws 0 $base64Key "base64"]
if {$success == 0} then {
puts [CkJws_lastErrorText $jws]
delete_CkJws $jws
delete_CkJsonObject $header
exit
}
# Create the JWS and write it into a StringBuilder.
set sbJws [new_CkStringBuilder]
set success [CkJws_CreateJwsSb $jws $sbJws]
if {$success == 0} then {
puts [CkJws_lastErrorText $jws]
delete_CkJws $jws
delete_CkJsonObject $header
delete_CkStringBuilder $sbJws
exit
}
puts [CkStringBuilder_getAsString $sbJws]
delete_CkJws $jws
delete_CkJsonObject $header
delete_CkStringBuilder $sbJws