Lua

Load a JWE from a StringBuilder

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.LoadJweSb, which loads a JWE from a StringBuilder (here read from a file) so it can be decrypted.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

Background. JWE (JSON Web Encryption) protects content with a content-encryption algorithm (the header enc value) while the content-encryption key is managed by the key-management algorithm (the header alg value). This example uses AES key wrapping with a symmetric wrapping key.

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Lua

local chilkat = require("chilkat")

local jwe = chilkat.Jwe.new()

-- The file path is relative to the application's current working directory.  An absolute path may
-- also be used.  Supply the path appropriate to your own environment.

-- Load the JWE text from a file into a StringBuilder.
local sbJwe = chilkat.StringBuilder.new()
local bLoaded = sbJwe:load_file("qa_data/message.jwe", "utf-8")
if not bLoaded then
    print("Failed to load the JWE file.")
    return
end

-- Load the JWE from the StringBuilder.
local success = jwe:load_jwe_sb(sbJwe)
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

local content = jwe:decrypt(0, "utf-8")
if not jwe.last_method_success then
    print(jwe.last_error_text)
    return
end

print(content)