Disclaimer: I have previously posted this question multiple times but the answers were always either incorrect or incomplete. Also in the comments, no one answered. Please read through the steps well as each part is required. I've been provided with two codes many times and I don't understand any of them ( there is no clear explanation using comments) and NONE of the codes run on any Online Compilers.

Question)

Subject: Information Security

Title: HMAC: Hash-based Message Authentication Code

Steps: You are required to design the crypto system. 1. System design: provide step by step implementation of the encryption algorithm of Hash-based Message Authentication Code

2. Testing and error correction: Test each part of the design and list the errors you encountered during the design process (a table that describes each error separately)

3. Include diagrams

NOTE!!!! : The implementation can be written in C Language Code ( with COMMENTS because I am not familiar with C Language and I need to understand the meaning of each line of code) or done using Excel Functions.

Thank you !

Code 1 that was answered by Chegg study experts:

#include "msp430x26x.h" #include "TI_SHA2.h" /* The following code example shows a hashing of a message using SHA-224. Although an array of eight 32-bit words are used for the hashing process, only the first seven 32-bit words are used as the hash result. */ uint32_t M[32]; //Message array to be hashed uint64_t L = 0x0000000000000000; //Bit Length of message to be hashed uint32_t Ha[8]; // Hash Array to be used during calculation and to store result int main( void ) { M[0] =0x41424344; //Data M[1] =0x45464748; //Data M[2] =0x494A4B4C; //Data L = 0x0000000000000060 //Length == 96 bits or 0x60 bits SHA_256(M, L, Ha, 0); // "0" indicates SHA-224 mode.

} return 0;

Code 2 that was answered by Chegg study experts:

#include #include #include

int main() { //-------------------------------------------------------------------- // Declare variables. // // hProv: Handle to a cryptographic service provider (CSP). // This example retrieves the default provider for // the PROV_RSA_FULL provider type. // hHash: Handle to the hash object needed to create a hash. // hKey: Handle to a symmetric key. This example creates a // key for the RC4 algorithm. // hHmacHash: Handle to an HMAC hash. // pbHash: Pointer to the hash. // dwDataLen: Length, in bytes, of the hash. // Data1: Password string used to create a symmetric key. // Data2: Message string to be hashed. // HmacInfo: Instance of an HMAC_INFO structure that contains // information about the HMAC hash. // HCRYPTPROV hProv = NULL; HCRYPTHASH hHash = NULL; HCRYPTKEY hKey = NULL; HCRYPTHASH hHmacHash = NULL; PBYTE pbHash = NULL; DWORD dwDataLen = 0; BYTE Data1[] = {0x70,0x61,0x73,0x73,0x77,0x6F,0x72,0x64}; BYTE Data2[] = {0x6D,0x65,0x73,0x73,0x61,0x67,0x65}; HMAC_INFO HmacInfo;

//-------------------------------------------------------------------- // Zero the HMAC_INFO structure and use the SHA1 algorithm for // hashing.

ZeroMemory(&HmacInfo, sizeof(HmacInfo)); HmacInfo.HashAlgid = CALG_SHA1;

//-------------------------------------------------------------------- // Acquire a handle to the default RSA cryptographic service provider.

if (!CryptAcquireContext( &hProv, // handle of the CSP NULL, // key container name NULL, // CSP name PROV_RSA_FULL, // provider type CRYPT_VERIFYCONTEXT)) // no key access is requested { printf(" Error in AcquireContext 0x%08x ", GetLastError()); goto ErrorExit; }

//-------------------------------------------------------------------- // Derive a symmetric key from a hash object by performing the // following steps: // 1. Call CryptCreateHash to retrieve a handle to a hash object. // 2. Call CryptHashData to add a text string (password) to the // hash object. // 3. Call CryptDeriveKey to create the symmetric key from the // hashed password derived in step 2. // You will use the key later to create an HMAC hash object.

if (!CryptCreateHash( hProv, // handle of the CSP CALG_SHA1, // hash algorithm to use 0, // hash key 0, // reserved &hHash)) // address of hash object handle { printf("Error in CryptCreateHash 0x%08x ", GetLastError()); goto ErrorExit; }

if (!CryptHashData( hHash, // handle of the hash object Data1, // password to hash sizeof(Data1), // number of bytes of data to add 0)) // flags { printf("Error in CryptHashData 0x%08x ", GetLastError()); goto ErrorExit; }

if (!CryptDeriveKey( hProv, // handle of the CSP CALG_RC4, // algorithm ID hHash, // handle to the hash object 0, // flags &hKey)) // address of the key handle { printf("Error in CryptDeriveKey 0x%08x ", GetLastError()); goto ErrorExit; }

//-------------------------------------------------------------------- // Create an HMAC by performing the following steps: // 1. Call CryptCreateHash to create a hash object and retrieve // a handle to it. // 2. Call CryptSetHashParam to set the instance of the HMAC_INFO // structure into the hash object. // 3. Call CryptHashData to compute a hash of the message. // 4. Call CryptGetHashParam to retrieve the size, in bytes, of // the hash. // 5. Call malloc to allocate memory for the hash. // 6. Call CryptGetHashParam again to retrieve the HMAC hash.

if (!CryptCreateHash( hProv, // handle of the CSP. CALG_HMAC, // HMAC hash algorithm ID hKey, // key for the hash (see above) 0, // reserved &hHmacHash)) // address of the hash handle { printf("Error in CryptCreateHash 0x%08x ", GetLastError()); goto ErrorExit; }

if (!CryptSetHashParam( hHmacHash, // handle of the HMAC hash object HP_HMAC_INFO, // setting an HMAC_INFO object (BYTE*)&HmacInfo, // the HMAC_INFO object 0)) // reserved { printf("Error in CryptSetHashParam 0x%08x ", GetLastError()); goto ErrorExit; }

if (!CryptHashData( hHmacHash, // handle of the HMAC hash object Data2, // message to hash sizeof(Data2), // number of bytes of data to add 0)) // flags { printf("Error in CryptHashData 0x%08x ", GetLastError()); goto ErrorExit; }

//-------------------------------------------------------------------- // Call CryptGetHashParam twice. Call it the first time to retrieve // the size, in bytes, of the hash. Allocate memory. Then call // CryptGetHashParam again to retrieve the hash value.

if (!CryptGetHashParam( hHmacHash, // handle of the HMAC hash object HP_HASHVAL, // query on the hash value NULL, // filled on second call &dwDataLen, // length, in bytes, of the hash 0)) { printf("Error in CryptGetHashParam 0x%08x ", GetLastError()); goto ErrorExit; }

pbHash = (BYTE*)malloc(dwDataLen); if(NULL == pbHash) { printf("unable to allocate memory "); goto ErrorExit; } if (!CryptGetHashParam( hHmacHash, // handle of the HMAC hash object HP_HASHVAL, // query on the hash value pbHash, // pointer to the HMAC hash value &dwDataLen, // length, in bytes, of the hash 0)) { printf("Error in CryptGetHashParam 0x%08x ", GetLastError()); goto ErrorExit; }

// Print the hash to the console.

printf("The hash is: "); for(DWORD i = 0 ; i < dwDataLen ; i++) { printf("%2.2x ",pbHash[i]); } printf(" ");

// Free resources. ErrorExit: if(hHmacHash) CryptDestroyHash(hHmacHash); if(hKey) CryptDestroyKey(hKey); if(hHash) CryptDestroyHash(hHash); if(hProv) CryptReleaseContext(hProv, 0); if(pbHash) free(pbHash); return 0; }