Random Byte Generator. This form allows you to generate random bytes. The randomness comes from atmospheric noise, which for many purposes is better than the pseudo-random number algorithms typically used in computer programs.

Symmetric Ciphers Online allows you to encrypt or decrypt arbitrary message using several well known symmetric encryption algorithms such as AES, 3DES, or BLOWFISH. Symmetric ciphers use the same (or very similar from the algorithmic point of view) keys for both encryption and decryption of a message. The all-in-one ultimate online toolbox that generates all kind of keys! Every coder needs All Keys Generator in its favorites! It is provided for free and only supported by ads and donations.

Syntax

Parameters

hProv

Handle of a cryptographic service provider (CSP) created by a call toCryptAcquireContext.

dwLen

Number of bytes of random data to be generated.

pbBuffer

Buffer to receive the returned data. This buffer must be at least dwLen bytes in length.

Optionally, the application can fill this buffer with data to use as an auxiliary random seed.

Return value

If the function succeeds, the return value is nonzero (TRUE).

If the function fails, the return value is zero (FALSE). For extended error information, callGetLastError.

The error codes prefaced by 'NTE' are generated by the particular CSP being used. Some possible error codes are listed in the following table.

Remarks

The data produced by this function is cryptographically random. It is far more random than the data generated by the typical random number generator such as the one shipped with your C compiler.

This function is often used to generate random initialization vectors and salt values.

Software random number generators work in fundamentally the same way. They start with a random number, known as the seed, and then use an algorithm to generate a pseudo-random sequence of bits based on it. The most difficult part of this process is to get a seed that is truly random. This is usually based on user input latency, or the jitter from one or more hardware components.

With Microsoft CSPs, CryptGenRandom uses the same random number generator used by other security components. This allows numerous processes to contribute to a system-wide seed. CryptoAPI stores an intermediate random seed with every user. To form the seed for the random number generator, a calling application supplies bits it might have—for instance, mouse or keyboard timing input—that are then combined with both the stored seed and various system data and user data such as the process ID and thread ID, the system clock, the system time, the system counter, memory status, free disk clusters, the hashed user environment block. This result is used to seed the pseudorandom number generator (PRNG). In Windows Vista with Service Pack 1 (SP1) and later, an implementation of the AES counter-mode based PRNG specified in NIST Special Publication 800-90 is used. In Windows Vista, Windows Storage Server 2003, and Windows XP, the PRNG specified in Federal Information Processing Standard (FIPS) 186-2 is used. If an application has access to a good random source, it can fill the pbBuffer buffer with some random data before calling CryptGenRandom. The CSP then uses this data to further randomize its internal seed. It is acceptable to omit the step of initializing the pbBuffer buffer before calling CryptGenRandom.

Examples

The following example shows the generation of 8 random bytes. These can be used to create cryptographic keys or for any application that uses random numbers. For an example that includes the complete context for this example, see Example C Program: Duplicating a Session Key.

Requirements

See also

Syntax

Parameters

hProv

Handle of a cryptographic service provider (CSP) created by a call toCryptAcquireContext.

dwLen

Number of bytes of random data to be generated.

pbBuffer

Buffer to receive the returned data. This buffer must be at least dwLen bytes in length.

Optionally, the application can fill this buffer with data to use as an auxiliary random seed.

Return value

If the function succeeds, the return value is nonzero (TRUE).

If the function fails, the return value is zero (FALSE). For extended error information, callGetLastError.

The error codes prefaced by 'NTE' are generated by the particular CSP being used. Some possible error codes are listed in the following table.

Remarks

The data produced by this function is cryptographically random. It is far more random than the data generated by the typical random number generator such as the one shipped with your C compiler.

This function is often used to generate random initialization vectors and salt values.

64 Bit Encryption Generator

Software random number generators work in fundamentally the same way. They start with a random number, known as the seed, and then use an algorithm to generate a pseudo-random sequence of bits based on it. The most difficult part of this process is to get a seed that is truly random. This is usually based on user input latency, or the jitter from one or more hardware components.

With Microsoft CSPs, CryptGenRandom uses the same random number generator used by other security components. This allows numerous processes to contribute to a system-wide seed. CryptoAPI stores an intermediate random seed with every user. To form the seed for the random number generator, a calling application supplies bits it might have—for instance, mouse or keyboard timing input—that are then combined with both the stored seed and various system data and user data such as the process ID and thread ID, the system clock, the system time, the system counter, memory status, free disk clusters, the hashed user environment block. This result is used to seed the pseudorandom number generator (PRNG). In Windows Vista with Service Pack 1 (SP1) and later, an implementation of the AES counter-mode based PRNG specified in NIST Special Publication 800-90 is used. In Windows Vista, Windows Storage Server 2003, and Windows XP, the PRNG specified in Federal Information Processing Standard (FIPS) 186-2 is used. If an application has access to a good random source, it can fill the pbBuffer buffer with some random data before calling CryptGenRandom. The CSP then uses this data to further randomize its internal seed. It is acceptable to omit the step of initializing the pbBuffer buffer before calling CryptGenRandom.

32 Byte Encryption Key Generator Software

Examples

The following example shows the generation of 8 random bytes. These can be used to create cryptographic keys or for any application that uses random numbers. For an example that includes the complete context for this example, see Example C Program: Duplicating a Session Key.

Requirements

128 Bit Encryption Key Generator

32 Byte Encryption Key Generator Download

See also