(Tcl) Load RSA Public Key from JWK Format (JSON Web Key)

Demonstrates how to load an RSA public key from JWK (JSON Web Key) format.

Note: This example requires Chilkat v9.5.0.66 or later.

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load ./chilkat.dll

# Note: This example requires Chilkat v9.5.0.66 or later.

# First build a JWK sample to load..
set json [new_CkJsonObject]

CkJsonObject_UpdateString $json "kty" "RSA"
CkJsonObject_UpdateString $json "n" "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw"
CkJsonObject_UpdateString $json "e" "AQAB"

# The JSON contains the following:
# { 
#   "kty": "RSA",
#   "n": "33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf-kDQiNSe2ZtqC7bnIc8-KSG_qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5-UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3_Q0auBkdbDR_ES2PbgKTJdkjc_rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw",
#   "e": "AQAB",
# } 

# Note: The JSON can contain other members, such as "use", "kid", or anything else.  These will be ignored.
CkJsonObject_put_EmitCompact $json 0

# Show the JWK string to be loaded:
set jwkStr [CkJsonObject_emit $json]

set pubKey [new_CkPublicKey]

# The LoadFromString method will automatically detect the format.
set success [CkPublicKey_LoadFromString $pubKey $jwkStr]
if {$success != 1} then {
    puts [CkPublicKey_lastErrorText $pubKey]
    delete_CkJsonObject $json
    delete_CkPublicKey $pubKey
    exit
}

# OK.. the JWK is loaded.  It can be used in whatever way desired...

# The key can be retrieved in any other format, such as XML or PEM..
puts [CkPublicKey_getXml $pubKey]

# XML output:
# <RSAPublicKey>
#     <Modulus>33TqqLR3eeUmDtHS89qF3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7sJp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwFwnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUEf0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1WSw==</Modulus>
#     <Exponent>AQAB</Exponent>
# </RSAPublicKey>

# Choose PCKS1 or PCKS8 PEM format..
set bPreferPkcs1 0
puts [CkPublicKey_getPem $pubKey $bPreferPkcs1]

# PEM output
# -----BEGIN PUBLIC KEY-----
# MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA33TqqLR3eeUmDtHS89qF
# 3p4MP7Wfqt2Zjj3lZjLjjCGDvwr9cJNlNDiuKboODgUiT4ZdPWbOiMAfDcDzlOxA
# 04DDnEFGAf+kDQiNSe2ZtqC7bnIc8+KSG/qOGQIVaay4Ucr6ovDkykO5Hxn7OU7s
# Jp9TP9H0JH8zMQA6YzijYH9LsupTerrY3U6zyihVEDXXOv08vBHk50BMFJbE9iwF
# wnxCsU5+UZUZYw87Uu0n4LPFS9BT8tUIvAfnRXIEWCha3KbFWmdZQZlyrFw0buUE
# f0YN3/Q0auBkdbDR/ES2PbgKTJdkjc/rEeM0TxvOUf7HuUNOhrtAVEN1D5uuxE1W
# SwIDAQAB
# -----END PUBLIC KEY-----

delete_CkJsonObject $json
delete_CkPublicKey $pubKey