def generate(bits, randfunc, progress_func=None):
    """Randomly generate a fresh, new ElGamal key.

    :Parameters:
        bits : int
            Key length, or size (in bits) of the modulus *p*.
            Recommended value is 2048.
        randfunc : callable
            Random number generation function; it should accept
            a single integer N and return a string of random data
            N bytes long.
        progress_func : callable
            Optional function that will be called with a short string
            containing the key parameter currently being generated;
            it's useful for interactive applications where a user is
            waiting for a key to be generated.

    :attention: You should always use a cryptographically secure random number generator,
        such as the one defined in the ``Crypto.Random`` module; **don't** just use the
        current time and the ``random`` module.

    :Return: An ElGamal key object (`ElGamalobj`).
    """
    obj=ElGamalobj()
    # Generate prime p
    if progress_func:
        progress_func('p\n')
    obj.p=bignum(getPrime(bits, randfunc))
    # Generate random number g
    if progress_func:
        progress_func('g\n')
    size=bits-1-(ord(randfunc(1)) & 63) # g will be from 1--64 bits smaller than p
    if size<1:
        size=bits-1
    while (1):
        obj.g=bignum(getPrime(size, randfunc))
        if obj.g < obj.p:
            break
        size=(size+1) % bits
        if size==0:
            size=4
    # Generate random number x
    if progress_func:
        progress_func('x\n')
    while (1):
        size=bits-1-ord(randfunc(1)) # x will be from 1 to 256 bits smaller than p
        if size>2:
            break
    while (1):
        obj.x=bignum(getPrime(size, randfunc))
        if obj.x < obj.p:
            break
        size = (size+1) % bits
        if size==0:
            size=4
    if progress_func:
        progress_func('y\n')
    obj.y = pow(obj.g, obj.x, obj.p)
    return obj
Weaknesses in this category are related to the design and implementation of data confidentiality and integrity. Frequently these deal with the use of encoding techniques, encryption libraries, and hashing algorithms. The weaknesses in this category could lead to a degradation of the quality data if they are not addressed.