When requesting Powercard, add merchantid=pre-registered merchantId in http header, e.g. merchantid=uu

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1. Generate RSA Key Pairs

Powercard uses AES(AES/ECB/PKCS5Padding) + RSA(RSA/ECB/PKCS1Padding) for service communication encryption/decryption. Merchants must apply for merchantId and keys before integration.

1. Powercard generates RSA Key Pair A (PKCS8 format, 2048-bit). A-publicKey is provided to merchant, A-privateKey is kept by Powercard

# Example: Pre-registered A-publicKey from Powercard:

# Example: Powercard's A-privateKey:

2. Merchant generates RSA Key Pair B (PKCS8 format, 2048-bit). B-publicKey is provided to Powercard, B-privateKey is kept by merchant

# Example: Merchant generates Key Pair B, provides B-publicKey to Powercard:

# Example: Merchant keeps B-privateKey securely:

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2. AES Encryption Process

Merchant must AES-encrypt requestBody with 32-character random string for each API call

1. Generate random string as AES key (32 characters):

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Encrypt AES key with RSA public key

# RequestBody Example:
{
	"channel": "merchantCards",
	"merchantId": "uu",
	"merchantUserId": "testUser123",
	"powerCardId": "a9f4cb3bfa8649b88853eded3ad853dd"
}

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3. RSA Encryption for AES Key

After completing the first two steps, the merchant uses A’s publicKey from the first step to RSA encrypt the AES Key from the second step, obtaining the final request key

# Encrypt AES key with RSA public key
aesRandomKey = 38859e263747adad524566278efa64c6

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4. Construct Final Request

After completing the first three steps, the merchant uses the data generated in the second step and the key generated in the third step to construct the final requestBody

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5. Response Decryption Process

Powercard encrypts responses using same method. Merchant should decrypt with B-privateKey to get pw-aesRandomkey, then decrypt data with AES key

1. Decrypt response with merchant’s B-privateKey to retrieve AES key: pw-aesRandomkey = RSADecrypt(response.key, B-privateKey)

2. Decrypt response data with obtained AES key: responseBody = AESDecrypt(response.data, pw-aesRandomkey)

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