Tcl

Load a JWE from a String

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.LoadJwe, which loads a JWE from its compact serialization string so it can be decrypted.

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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Tcl


load ./chilkat.dll

set success 0

set jwe [new_CkJwe]

#  Load a JWE from its compact serialization string.
set jweCompact "eyJhbGciOiJBMjU2S1ciLCJlbmMiOiJBMjU2R0NNIn0.<...>.<iv>.<ciphertext>.<tag>"
set success [CkJwe_LoadJwe $jwe $jweCompact]
if {$success == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    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
    exit
}

#  The loaded JWE can now be decrypted.
set content [CkJwe_decrypt $jwe 0 "utf-8"]
if {[CkJwe_get_LastMethodSuccess $jwe] == 0} then {
    puts [CkJwe_lastErrorText $jwe]
    delete_CkJwe $jwe
    exit
}

puts "$content"

delete_CkJwe $jwe