RSA Crypto Algo information

1. RSA Encryption
• RSA is an asymmetric cryptography algorithm.
 Key Generation: Generating the keys to be used for encrypting and decrypting the data to be exchanged.
 Encryption/Decryption Function: The steps that need to be run when scrambling and recovering the data.
RSA Digital Signature
Digital signatures are used to verify the authenticity of the message sent electronically.
RSA – Rivest, Shamir, Adleman

2. What Is Asymmetric Encryption?

3. Public/Private Key Generation
• Public Key: Select two prime no's. Suppose P = 53 and Q = 59.
Now First part of the Public key : n = P*Q = 3127
Now z = (p-1)(q-1), Choose a number e where 1 < e < z. Let us now consider e as 3
c = (PQ^e) mod n
Our Public Key is made of n and e
• Private Key: We need to calculate Φ(n) :
Such that Φ(n) = (P-1)(Q-1)
so, Φ(n) = (53-1)(59-1)=(52)(58)=3016
Now calculate Private Key, d :
d = (k*Φ(n) + 1) / e for some integer k
For k = 2, d = (2*3016+1)/3 = (6032+1)/3 = (6033)/3 = 2011
value of d is 2011.

4. Let us encrypt/decrypt…
Now we are ready with our – Public Key ( n = 3127 and e = 3) and Private Key(d = 2011)
• Let us encrypt “HI”:
Convert letters to numbers : H = 8 and I = 9
Encrypted Data c = (ab^e) mod n
Encrypted Data c = (89e)mod n = (89*89*89)mod 3127 = (704969) mod 3127
Encrypted Data comes out to be 1394
• Now we will decrypt 1394 :
Decrypted Data = (c^d)mod n
Decrypted Data = (1394^d) mod 3127 = 89
Encrypted Data comes out to be 89
8 = H and I = 9 i.e. "HI".

5. RSA Digital Signature

6. RSA Digital Signature…

7. Code pointers
• integ_rsa_encrypt.c
• integ_rsa_decrypt.c
• integ_rsa_keygen.c
typedef struct _CpaCyRsaKeyGenOpData {
CpaFlatBuffer prime1P;
CpaFlatBuffer prime2Q;
Cpa32U modulusLenInBytes;
CpaCyRsaVersion version;
CpaCyRsaPrivateKeyRepType privateKeyRepType;
CpaFlatBuffer publicExponentE;
} CpaCyRsaKeyGenOpData;
Integ code
isg_cid_qat_sal/me_acceleration_layer/access_layer/look_aside_acceleration/integ_test/common/crypto/asym/rsa
typedef struct _CpaCyRsaEncryptOpData {
CpaCyRsaPublicKey *pPublicKey;
/**< Pointer to the public key. */
CpaFlatBuffer inputData;
/**< The input data that the RSA encryption primitive operation is
* performed on. The data pointed to is an integer that MUST be in big-
* endian order. The value MUST be between 0 and the modulus n - 1. */
} CpaCyRsaEncryptOpData;
typedef struct _CpaCyRsaDecryptOpData {
CpaCyRsaPrivateKey *pRecipientPrivateKey;
/**< Pointer to the recipient's RSA private key. */
CpaFlatBuffer inputData;
/**< The input data that the RSA decryption primitive operation is
* performed on. The data pointed to is an integer that MUST be in big-
* endian order. The value MUST be between 0 and the modulus n - 1. */
} CpaCyRsaDecryptOpData;

8. Code pointers…
Key Generation
LacIntegRsa_AllocKeyGenData
-LacIntegPke_CreatePrivateKey
-LacIntegPke_CreatePublicKey
LacIntegRsa_KeySendReq
-LacIntegRsa_KeySend
-cpaCyRsaGenKey -> SAL code
Encryption
LacIntegRsa_EncryptInt/LacIntegRsa_EncPerfTestInt
-LacIntegRsa_AllocEncData
-LacIntegPke_CreatePublicKey
-LacIntegPke_PopulateFlatBuffer
LacIntegRsa_EncPerfTestInt
-LacIntegRsa_EncSendReq
-LacIntegRsa_EncSend
-cpaCyRsaEncrypt ->SAL code
Decryption
LacIntegRsa_Decrypt1Int
->LacIntegRsa_AllocDec1Data
->LacIntegPke_CreatePrivateKey1
->LacIntegPke_PopulateFlatBuffer
LacIntegRsa_DecPerfTestInt
LacIntegRsa_DecSendReq
->LacIntegRsa_DecSend
->cpaCyRsaDecrypt -> SAL code