const char *proxytype(proxytypes_t proxytype)
{
	int i;

	for (i = 0; proxynames[i].name; i++)
		if (proxynames[i].proxytype == proxytype)
			return proxynames[i].name;

	return "invalid";
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.