1. A system comprising: at least one processor; a memory; and an intrusion prevention mechanism stored in the memory and including instructions, which are executable by the at least one processor and include an analysis engine configured to tokenize an input stream of data into a plurality of parts including a first one or more parts and a second one or more parts, and select the first one or more parts for analysis, wherein the analysis engine includes one or more protocol parsers, and wherein the one or more protocol parsers analyze the first one or more parts, and a generic decoder configured to operate based on generic application-level protocol analysis language primitives, wherein the generic decoder is configured to assist the one or more protocol parsers of the analysis engine by analyzing the second one or more parts, having a same protocol as the first one or more parts and not analyzed by the analysis engine, for a signature, wherein the analyzing of the second one or more parts includes searching the second one or more parts for a first predetermined pattern, and generate an error signal in response to matching the first predetermined pattern in the second one or more parts, wherein the signature is detected in response to the pattern being matched in the second one or more parts, and wherein the primitives include at least one of a primitive configured for pattern matching, a primitive configured for skipping a first predetermined number of bytes to search for the first predetermined pattern, a primitive configured for specifying a window in which at least one pattern is to be searched, a primitive configured for using a regular expression for pattern matching, or a primitive configured for reading a value and moving within the first one or more parts based on that value.