Set a Per-Recipient JWE Header

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.SetRecipientHeader, which sets the per-recipient unprotected header for a recipient index.

load ./chilkat.dll

set success 0

set jwe [new_CkJwe]

#  Protected header: AES key-wrap with AES-256-GCM content encryption.
set header [new_CkJsonObject]

CkJsonObject_UpdateString $header "alg" "A256KW"
CkJsonObject_UpdateString $header "enc" "A256GCM"
set success [CkJwe_SetProtectedHeader $jwe $header]
if {$success == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    delete_CkJsonObject $header
    exit
}

#  The 256-bit key-wrapping key (base64) for recipient index 0.  In production, obtain the key from a
#  secure source rather than hard-coding it.
set base64Key "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
set success [CkJwe_SetWrappingKey $jwe 0 $base64Key "base64"]
if {$success == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    delete_CkJsonObject $header
    exit
}

#  Set the per-recipient unprotected header for recipient 0, for example a key id used to identify
#  which key a recipient should use.
set recipHeader [new_CkJsonObject]

CkJsonObject_UpdateString $recipHeader "kid" "recipient-key-1"
set success [CkJwe_SetRecipientHeader $jwe 0 $recipHeader]
if {$success == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    delete_CkJsonObject $header
    delete_CkJsonObject $recipHeader
    exit
}

set sbContent [new_CkStringBuilder]

CkStringBuilder_Append $sbContent "This is the secret content."
set sbJwe [new_CkStringBuilder]

set success [CkJwe_EncryptSb $jwe $sbContent "utf-8" $sbJwe]
if {$success == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    delete_CkJsonObject $header
    delete_CkJsonObject $recipHeader
    delete_CkStringBuilder $sbContent
    delete_CkStringBuilder $sbJwe
    exit
}

puts [CkStringBuilder_getAsString $sbJwe]

delete_CkJwe $jwe
delete_CkJsonObject $header
delete_CkJsonObject $recipHeader
delete_CkStringBuilder $sbContent
delete_CkStringBuilder $sbJwe