Abstract: A multi-rule approach for encoding rules grouped in a rule chunk is provided. The approach includes a multi-rule with a multi-rule header representing headers of the rules and, in some cases, dimensional data representing dimensional data of the rules. The approach further includes disabling dimension matching of always matching dimensions, responding to an always match rule with a match response without matching, interleaving minimum/maximum values in a range field, interleaving value/mask values in a mask field, and for a given rule of rule chunk, encoding a priority field at the end of dimension data stored for the rule in the multi-rule. Advantageously, this approach provides efficient storage of rules and enables the efficient comparison of rules to keys.

Abstract: A method, and corresponding apparatus, of managing processing thread migrations within a plurality of memory clusters, includes embedding, in memory components of the plurality of memory clusters, instructions indicative of processing thread migrations; storing, in one or more memory components of a particular memory cluster among the plurality of memory clusters, data configured to designate the particular memory cluster as a sink memory cluster, the sink memory cluster preventing an incoming migrated processing thread from migrating out of the sink memory cluster; and processing one or more processing threads, in one or more of the plurality of memory clusters, in accordance with at least one of the embedded migration instructions and the data stored in the one or more memory components of the sink memory cluster.

Abstract: A method and apparatus relate to recognizing anchored patterns from an input stream. Patterns from a plurality of given patterns are marked as anchored patterns. An anchored state tree for the anchored patterns of the plurality of given patterns is built, including nodes representing a state of the anchored state tree. For each node of the anchored state tree, a failure value equivalent to a node representing a state in an unanchored state tree representing unanchored patterns of the plurality of given patterns is determined.

Abstract: In one embodiment, a method of walking a non-deterministic finite automata (NFA) graph representing a pattern includes extracting a node type and an element from a node of the NFA graph. The method further includes matching a segment of a payload for the element by matching the payload for the element at least zero times, the number of times based on the node type.

Abstract: Nodes of a per-pattern NFA may be stored amongst one or more of a plurality of memories based on a node distribution determined as a function of hierarchical levels mapped to the plurality of memories and per-pattern NFA storage allocation settings configured for the hierarchical levels. At least one processor may be configured to cache one or more nodes of the per-pattern NFA in the node cache based on a cache miss of a given node of the one or more nodes and a hierarchical node transaction size associated with a given hierarchical level mapped to a given memory in which the given node is stored, optimizing run time performance of the walk.

Abstract: In an embodiment, a method of updating a memory with a plurality of memory lines, the memory storing a tree, a plurality of buckets, and a plurality of rules, includes maintaining a copy of the memory with a plurality of memory lines. The method further includes writing a plurality of changes to at least one of the tree, the plurality of buckets, and the plurality of rules to the copy. The method further includes determining whether each of the plurality of changes is an independent write or a dependent write. The method further includes merging independent writes to the same line of the copy. The method further includes transferring updates from the plurality of lines of the copy to the plurality of lines of the memory.

Abstract: A method and corresponding apparatus for run time processing use a Deterministic Finite Automata (DFA) and Non-Deterministic Finite Automata (NFA) to find the existence of a pattern in a payload. A subpattern may be selected from each pattern in a set of one or more regular expression patterns based on at least one heuristic. The DFA may be generated from selected subpatterns from all patterns in the set, and at least one NFA may be generated for at least one pattern in the set, optimizing run time performance of the run time processing.

Abstract: A method and corresponding apparatus are provided implementing run time processing using Deterministic Finite Automata (DFA) and Non-Deterministic Finite Automata (NFA) to find the existence of a pattern in a payload. A subpattern may be selected from each pattern in a set of one or more regular expression patterns based on at least one heuristic and a unified deterministic finite automata (DFA) may be generated using the subpatterns selected from all patterns in the set, and at least one non-deterministic finite automata (NFA) may be generated for at least one pattern in the set, optimizing run time performance of the run time processing.

Abstract: A method, and corresponding apparatus and system are provided for optimizing matching at least one regular expression pattern in an input stream by walking at least one finite automaton in a speculative manner. The speculative manner may include walking at least two nodes of a given finite automaton, of the at least one finite automaton, in parallel, with a segment, at a given offset within a payload of a packet in the input stream. The walking may include determining a match result for the segment, at the given offset within the payload, at each node of the at least two nodes. The walking may further include determining at least one subsequent action for walking the given finite automaton, based on an aggregation of each match result determined.

Abstract: A method and apparatus relate to recognizing anchored patterns from an input stream. Patterns from a plurality of given patterns are marked as anchored patterns. An anchored state tree for the anchored patterns of the plurality of given patterns is built, including nodes representing a state of the anchored state tree. For each node of the anchored state tree, a failure value equivalent to a node representing a state in an unanchored state tree representing unanchored patterns of the plurality of given patterns is determined.

Abstract: In a processor of a security appliance, an input of a sequence of characters is walked through a finite automata graph generated for at least one given pattern. At a marked node of the finite automata graph, if a specific type of the at least one given pattern is matched at the marked node, the input sequence of characters is processed through a reverse non-deterministic finite automata (rNFA) graph generated for the specific type of the at least one given pattern by walking the input sequence of characters backwards through the rNFA beginning from an offset of the input sequence of characters associated with the marked node. Generating the rNFA for a given pattern includes inserting processing nodes for processing an input sequence of patterns to determine a match for the given pattern. In addition, the rNFA is generated from the given type of pattern.

Abstract: In a processor of a security appliance, an input of a sequence of characters is walked through a finite automata graph generated for at least one given pattern. At a marked node of the finite automata graph, if a specific type of the at least one given pattern is matched at the marked node, the input sequence of characters is processed through a reverse non-deterministic finite automata (rNFA) graph generated for the specific type of the at least one given pattern by walking the input sequence of characters backwards through the rNFA beginning from an offset of the input sequence of characters associated with the marked node. Generating the rNFA for a given pattern includes inserting processing nodes for processing an input sequence of patterns to determine a match for the given pattern. In addition, the rNFA is generated from the given type of pattern.

Abstract: A packet classification system, apparatus, and corresponding apparatus are provided for enabling packet classification. A processor of a security appliance coupled to a network uses a classifier table having a plurality of rules, the plurality of rules having at least one field, to build a decision tree structure for packet classification. Duplication in the decision tree may be identified, producing a wider, shallower decision tree that may result in shorter search times with reduced memory requirements for storing the decision tree. A number of operations needed to identify duplication in the decision tree may be reduced, thereby increasing speed and efficiency of a compiler building the decision tree.

Abstract: In a processor of a security appliance, an input of a sequence of characters is walked through a finite automata graph generated for at least one given pattern. At a marked node of the finite automata graph, if a specific type of the at least one given pattern is matched at the marked node, the input sequence of characters is processed through a reverse non-deterministic finite automata (rNFA) graph generated for the specific type of the at least one given pattern by walking the input sequence of characters backwards through the rNFA beginning from an offset of the input sequence of characters associated with the marked node. Generating the rNFA for a given pattern includes inserting processing nodes for processing an input sequence of patterns to determine a match for the given pattern. In addition, the rNFA is generated from the given type of pattern.

Abstract: A packet classification system, methods, and corresponding apparatus are provided for enabling packet classification. A processor of a security appliance coupled to a network uses a classifier table having a plurality of rules, the plurality of rules having at least one field, to build a decision tree structure including a plurality of nodes, the plurality of nodes including a subset of the plurality of rules. The methods may produce wider, shallower trees that result in shorter search times and reduced memory requirements for storing the trees.

Abstract: At least one per-pattern non-deterministic finite automaton (NFA) may be generated for a single regular expression pattern and may include a respective set of nodes. Nodes of the respective set of nodes of each per-pattern NFA generated may be distributed for storing in a plurality of memories based on hierarchical levels mapped to the plurality of memories and per-pattern NFA storage allocation settings configured for the hierarchical levels, optimizing run time performance for matching regular expression patterns in an input stream.

Abstract: Nodes of a per-pattern NFA may be stored amongst one or more of a plurality of memories based on a node distribution determined as a function of hierarchical levels mapped to the plurality of memories and per-pattern NFA storage allocation settings configured for the hierarchical levels. At least one processor may be configured to cache one or more nodes of the per-pattern NFA in the node cache based on a cache miss of a given node of the one or more nodes and a hierarchical node transaction size associated with a given hierarchical level mapped to a given memory in which the given node is stored, optimizing run time performance of the walk.

Abstract: At least one processor may be operatively coupled to a plurality of memories and a node cache and configured to walk nodes of a per-pattern non-deterministic finite automaton (NFA). Nodes of the per-pattern NFA may be stored amongst one or more of the plurality of memories based on a node distribution determined as a function of hierarchical levels mapped to the plurality of memories and per-pattern NFA storage allocation settings configured for the hierarchical levels, optimizing run time performance of the walk.

Abstract: A system, apparatus, and method are provided for adding, deleting, and modifying rules in one update from the perspective of an active search process for packet classification. While a search processor searches for one or more rules that match keys generated from received packets, there is a need to add, delete, or modify rules. By adding, deleting, and modifying rules in one update from the perspective of an active search process for packet classification, performance and functionality of the active search process may be maintained, thereby preventing packet loss and preserving throughput.

Abstract: A method, and corresponding apparatus and system are provided for optimizing matching of at least one regular expression pattern in an input stream by storing a context for walking a given node, of a plurality of nodes of a given finite automaton of at least one finite automaton, the store including a store determination, based on context state information associated with a first memory, for accessing the first memory and not a second memory or the first memory and the second memory. Further, to retrieve a pending context, the retrieval may include a retrieve determination, based on the context state information associated with the first memory, for accessing the first memory and not the second memory or the second memory and not the first memory. The first memory may have read and write access times that are faster relative to the second memory.