Fortinet, Inc.

Lin Huang

Xu Zhou

Michael Xie

David L Chen

Guansong Zhang

Zhi Guo

Hongbin Lu

Circuits and methods are provided for detecting, identifying and/or removing undesired content. According to one embodiment, a method for performing content scanning of content objects is provided. A content object that is to be scanned is stored by a general purpose processor to a system memory of the general purpose processor. Content scanning parameters associated with the content object are set up by the general purpose processor. Instructions from a signature memory of a co-processor that is coupled to the general purpose processor are read by the co-processor based on the content scanning parameters. The instructions contain op-codes of a first instruction type and op-codes of a second instruction type. Those of the instructions containing op-codes of the first instruction type are assigned by the co-processor to a first instruction pipe of multiple instruction pipes of the co-processor for execution. An instruction of the assigned instructions containing op-codes of the first instruction type is executed by the first instruction pipe including accessing a portion of the content object from the system memory.

Operation of a dual instruction pipe virus co-processor

Methods and systems for improving accuracy, speed, and efficiency of context-aware pattern matching are provided. According to one embodiment, a packet stream is received by a first stage of a hardware accelerator of a network device. A pre-matching process is performed by the first stage to identify a candidate packet that matches a string or over-flow pattern associated with access control (e.g., IPS or ADC) rules. A candidate rule is identified based on a correlation of results of the pre-matching process. The candidate packet is tokened to produce matching tokens and corresponding locations. A full-match process is performed on the candidate packet by a second stage of the hardware accelerator to determine whether it satisfies the candidate rule by performing one or more of (i) context-aware pattern matching, (ii) context-aware string matching and (iii) regular expression matching based on contextual information, the matching tokens and the corresponding locations.

Context-aware pattern matching accelerator

Methods and systems for a more efficient transmission of network traffic are provided. According to one embodiment, presence of outbound payload data, distributed across a first and second payload buffer, within a user memory space of a network device that has been generated by a user process is determined by a bus/memory interface or a network interface unit. The payload data is fetched by performing direct virtual memory addressing of the user memory space including mapping virtual addresses of the payload buffers to corresponding physical addresses, including: (i) when the payload buffers are noncontiguous, then retrieving the outbound payload data with reference to multiple buffer descriptors having starting virtual addresses of the payload buffers and (ii) when they are contiguous, then retrieving the outbound payload data with reference to a single buffer descriptor. The outbound payload data is then segmented across one or more TCP packets.

Virtual memory protocol segmentation offloading

Circuits and methods are provided for detecting, identifying and/or removing undesired content. According to one embodiment, a processor maintains a page directory and a page table within a system memory for use in connection with translating virtual addresses to physical addresses. Content scanning of a content object is offloaded to a hardware accelerator coupled to the processor by storing content scanning parameters, including the content object and a type of the content object, to the memory using one or more virtual addresses and indicating to the hardware accelerator that the content object is available for content scanning. Responsive thereto, the hardware accelerator: (i) translates the virtual addresses to corresponding physical addresses based on one or more of the page directory and the page table; (ii) accesses scanning parameters based on the physical addresses; (iii) scans the content object for undesirable content by applying multiple signatures; and (iv) returns a result of the content scanning to the processor.

Efficient data transfer in a virus co-processing system

Circuits and methods are provided for detecting, identifying and/or removing undesired content. According to one embodiment, a content object that is to be virus processed is stored by a general purpose processor to a system memory. Virus scan parameters for the content object are set up by the general purpose processor. Instructions from a virus signature memory of a virus co-processor are read by the virus co-processor based on the virus scan parameters. The instructions contain op-codes of a first instruction type and op-codes of a second instruction type. Those of the instructions containing op-codes of the first instruction type are assigned to a first instruction pipe of multiple instruction pipes of the virus co-processor for execution. An instruction of the assigned instructions containing op-codes of the first instruction type is executed by the first instruction pipe including accessing a portion of the content object from the system memory.

Methods and systems for improving accuracy, speed, and efficiency of context-aware pattern matching are provided. According to one embodiment, a packet stream is received by a first stage of a CPMP hardware accelerator of a network device. A pre-matching process is performed by the first stage to identify a candidate packet that matches a string or over-flow pattern associated with IPS or ADC rules. A candidate rule is identified based on a correlation of results of the pre-matching process. The candidate packet is tokened to produce matching tokens and corresponding locations. A full-match process is performed on the candidate packet by a second stage of the CPMP hardware accelerator to determine whether it satisfies the candidate rule by performing one or more of (i) context-aware pattern matching, (ii) context-aware string matching and (iii) regular expression matching based on contextual information, the matching tokens and the corresponding locations.

Circuits and methods for detecting, identifying and/or removing undesired content are provided. According to one embodiment, a system includes a co-processor (CP), a first memory, a general purpose processor (GPP) and a second memory. The first memory is associated with the CP and coupled to the CP. The first memory includes a first signature compiled for execution on the CP. The GPP is coupled to the CP. The second memory is associated with the GPP and coupled to the CP and to the GPP. The second memory includes a second signature compiled for execution on the GPP. The CP is operable to retrieve the first signature stored within the first memory through an instruction cache. The CP is operable to retrieve a data segment to be scanned for undesirable content stored within the second memory through a data cache that is separate from the instruction cache.

Virus co-processor instructions and methods for using such

Circuits and methods are provided for detecting, identifying and/or removing undesired content. According to one embodiment, a processor maintains a page directory and a page table within a system memory that contain information for translating virtual addresses to physical addresses. Virus processing of a content object is offloaded to a hardware accelerator coupled to the processor by storing scanning parameters, including the content object and a type of the content object, to the memory using one or more virtual addresses and indicating to the hardware accelerator that the content object is available for processing. Responsive thereto, the hardware accelerator: (i) translates the virtual addresses to corresponding physical addresses based on the page directory and the page table; (ii) accesses the scanning parameters based on the physical addresses; (iii) scans the content object for viruses by applying multiple virus signatures; and (iv) returns a result of the scanning to the processor.

Circuits and methods for detecting, identifying and/or removing undesired content are provided. According to one embodiment, a virus processing system includes a virus co-processor, a first memory, a general purpose processor (GPP) and a second memory. The first memory is communicably coupled to the co-processor via a first memory interface. The first memory includes a first signature compiled for execution on the co-processor. The GPP is communicably coupled to the co-processor. The second memory is communicably coupled to the co-processor via a second memory interface and to the GPP. The second memory includes a second signature compiled for execution on the GPP. The co-processor is operable to retrieve the first signature stored within the first memory through an instruction cache. The co-processor is operable to retrieve a data segment to be scanned from second memory through a data cache that is separate from the instruction cache.

Methods and systems for a more efficient transmission of network traffic are provided. According to one embodiment, payload data originated by a user process running on a host processor of a network device is fetched by an interface of the network device by performing direct virtual memory addressing of a user memory space of a system memory of the network device on behalf of a network interface unit of the network device. The direct virtual memory addressing maps physical addresses of various portions of the payload data to corresponding virtual addresses. The payload data is segmented by the network interface unit across one or more packets.

Circuits and methods are provided for detecting, identifying and/or removing undesired content. According to one embodiment, a method for virus co-processing is provided. A general purpose processor stores a data segment to its system memory using a virtual address. The system memory has stored therein a page directory and a page table containing information for translating virtual addresses to physical addresses within a physical address space of the system memory. A virus processing hardware accelerator translates the virtual address of the data segment to a physical address of the data segment based on the page directory and the page table. The hardware accelerator accesses the data segment based on the physical address. The hardware accelerator scans the data segment for viruses by executing multiple pattern comparisons against the data segment. The hardware accelerator returns a result of the scanning to the general purpose processor via the system memory.

Methods and systems for a more efficient transmission of network traffic are provided. According to one embodiment, payload data originated by a user process running on a host processor of the computer system is fetched by an interface of the computer system by performing direct virtual memory addressing of a user memory space of a system memory of the computer system on behalf of a network processor of the computer system. The direct virtual memory addressing maps a physical address of the payload data to a virtual address. The payload data is segmented by the network processor across one or more packets.

Growing community of inventors

Fremont, CA, United States of America

Lin Huang