Set the Shared JWE Unprotected Header

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.SetUnprotectedHeader, which sets the shared JWE unprotected header from a JsonObject.

local chilkat = require("chilkat")

local jwe = chilkat.Jwe.new()

-- Protected header: AES key-wrap with AES-256-GCM content encryption.
local header = chilkat.JsonObject.new()
header:update_string("alg", "A256KW")
header:update_string("enc", "A256GCM")
local success = jwe:set_protected_header(header)
if not success then
    print(jwe.last_error_text)
    return
end

-- 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.
local base64Key = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU="
success = jwe:set_wrapping_key(0, base64Key, "base64")
if not success then
    print(jwe.last_error_text)
    return
end

-- Set the shared JWE unprotected header.  It is shared by all recipients but, unlike the protected
-- header, is not integrity-protected.
local unprotected = chilkat.JsonObject.new()
unprotected:update_string("cty", "text/plain")
success = jwe:set_unprotected_header(unprotected)
if not success then
    print(jwe.last_error_text)
    return
end

local sbContent = chilkat.StringBuilder.new()
sbContent:append("This is the secret content.")
local sbJwe = chilkat.StringBuilder.new()
success = jwe:encrypt_sb(sbContent, "utf-8", sbJwe)
if not success then
    print(jwe.last_error_text)
    return
end

print(sbJwe:get_as_string())