Afpacket. Raw network packet capture examples.

Afpacket In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmapped ring buffer, shared between user Nov 7, 2025 · AFPacket Module A DAQ module built on top of the Linux memory-mapped packet socket interface (AF_PACKET). Packet Capture Options Kubeshark supports numerous packet capture options catering to a wide range of kernel versions and available capabilities. topel@intel. Registration is quick, simple and absolutely free. conf Nov 20, 2021 · 6,969 downloads per month Used in 3 crates (via async-arp) MirOS license 20KB 411 lines afpacket Rust bindings for Linux AF_PACKET (raw) sockets, including Async wrapper for use with async_std or futures, based on async_io. struct sockaddr_ll { unsigned short sll_family; /* Always AF_PACKET */ unsigned short sll_protocol; /* Physical layer protocol */ int sll_ifindex; /* Interface number */ unsigned short sll_hatype; /* Header type */ unsigned char sll_pkttype; /* Packet type */ unsigned char sll_halen; /* Length of address */ unsigned raw(7) Miscellaneous Information Manual raw(7) NAME top raw - Linux IPv4 raw sockets SYNOPSIS top #include <sys/socket. The capture code is usually made in a single file and its associated header: src/source-af-packet. com> This RFC introduces AF_PACKET_V4 and PACKET_ZEROCOPY that are optimized for high performance packet processing and zero-copy semantics. c src/source-af-packet. These families May 9, 2021 · As AF_PACKET sockets are used for network sniffing tools such as tcpdump, Wireshark, etc, by default you will get all packets passing through the interface you bind on - incoming and outgoing packets. To use AFPACKET in passive mode: Oct 19, 2020 · Links Open Source InsightsDirectories Mar 1, 2022 · When you install an IDPS Sensor in an environment with a high traffic rate, it is preferred to run your sensor with AF-Packet. – packet (7) The AF_PACKET socket in Linux allows an application to receive and send raw packets. h> include file for a list of allowed protocols. eBPF How to Use: --set packetCapture=ebpf While eBPF is the most modern packet capture Jan 31, 2018 · From: Björn Töpel <bjorn. Having a variety of options to choose from guarantees traffic capture is performant and robust. The script available at https://github. com> This RFC introduces a new address family called AF_XDP that is optimized for high performance packet processing and zero-copy semantics. h> int socket(int domain, int type, int protocol); DESCRIPTION top socket () creates an endpoint for communication and returns a file descriptor that refers to that endpoint. Enable plugin for mirror capture: program 1 : af_packet raw single server and single client : single data transfer Plugin providing native AF_Packet support for Zeek. Note: This module is in testing and is not yet considered stable! 4. Multi-Buffer Support ¶ With multi-buffer support, programs using AF_XDP sockets can receive and transmit packets consisting of multiple buffers both in copy and zero-copy mode. 0. The main difference between V4 and V2/V3 is that TX and RX descriptors are program 1 : af_packet udp single server and single client : single data transfer Jan 5, 2019 · I'm very confused about exactly how the AF_PACKET socket family (for SOCK_RAW sockets) specifically relates to Ethernet (IEEE 802. XDP_OPTIONS getsockopt ¶ Gets options from an XDP socket. I finally tested it today and it failed! My . As the plugin Sep 16, 2013 · i just want to know that in python socket programming, when to use socket_PF_PACKET and when to use socket. Experimental results on a set of micro-benchmarks show performance improvements Mar 20, 2025 · Hi Jason, Thanks for the quick response. We suggest using separate interface for management connection with FastNetMon for reliability reasons. Packet MMAP ¶ Abstract ¶ This file documents the mmap () facility available with the PACKET socket interface. Hi, All Recently I found a big performance difference (~5Gbps vs. The link level header information is Jan 3, 2025 · AF_PACKET 链路层通信 目前大多数操作系统都为应用程序提供了访问数据链路层的手段，应用程序访问链路层可以监视链路层上收到的分组，这使得我们可以在普通计算机系统上通过像 tcpdump 这样的程序来监视网络，而无需使用特殊的硬件设备，如果使用网络接口的混杂模式，我们甚至可以侦听本地 packet PACKET(7) Linux Programmer's Manual PACKET(7) NAME packet - packet interface on device level SYNOPSIS #include <sys/socket. This results in a library dependency on libpcap at runtime for the AFPacket DAQ module. --runmode=autofp Notice: suricata: This is Suricata version 8. They allow the user to implement protocol modules in user space on top of the physical layer. Ive tried to look for the information in getifaddrs(), but t Abstract In this paper, the RFC of AF PACKET V4 and PACKET ZEROCOPY is presented and discussed. The file descriptor returned by a successful call will be the lowest-numbered file descriptor not currently open for the process. The point is that I want to be able to arbitrarily change the source MAC address an Mar 12, 2024 · This post was originally published on my Personal blog at Tagged with go, programming, devops, performance. tpacket-v3=true --set default-rule-path=. 2, Zeek ships with a built-in version of this plugin. The link-level header information is available in a common format in a sockaddr_ll structure. 04 - Linux distro for threat hunting, enterprise security monitoring, and log management - Security-Onion-Solutions/security-onion Aug 23, 2009 · How do I send data on a SOCK_PACKET socket without specifying which host it's bound for? I've constructed the IP header to show where it should go, but write() won't work. This plugin provides native AF_Packet support for Zeek. The AFPacket DAQ module will implement BPF filtering if the LibPCAP development headers and libraries are available at build time. Jan 17, 2022 · Consider an application that opens AF_PACKET socket to listen for packets on a specific interface. Contribute to torvalds/linux development by creating an account on GitHub. com/JustinAzoff/can-i-use-afpacket-fanout can be used to verify whether PACKET_FANOUT works as expected. /src/suricata -c suricata. h> int socket(int domain, int type, int protocol); DESCRIPTION top The domain argument of the socket(2) specifies a communication domain; this selects the protocol family which will be The Python interface is a straightforward transliteration of the Unix system call and library interface for sockets to Python’s object-oriented style: the socket() function returns a socket object whose methods implement the various socket system calls. Provides packet processing capabilities for Go. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. What I understand so far: I understand the OSI Model, and how afpacket. Note that this is the follow up RFC to AF_PACKET V4 from November last High-performance bindings for Linux kernel AF_PACKET interface - DominoTree/rs-af_packet Linux kernel source tree. h> /* the L2 protocols */ packet_socket = socket(AF_PACKET, int socket_type, int protocol); DESCRIPTION Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level. The socket_type is either SOCK_RAW for raw packets including the link-level header or SOCK_DGRAM for cooked packets with the link-level header removed. So, I assume you have already worked with network sockets before – if not, don't fear, it's not that hard and there are plenty of The AFPacket Module provides a Data Acquisition (DAQ) implementation based on the Linux memory-mapped packet socket interface (AF_PACKET). The domain argument specifies a communication domain; this selects the protocol family which will be used for communication. This means, for example, if you configure Suricata for 4 AF-PACKET threads then each thread would receive about 25% of the total traffic that AF-PACKET is seeing. h> /* See NOTES */ #include <sys/socket. Contribute to google/gopacket development by creating an account on GitHub. Oct 19, 2020 · afpacket provides a simple example of using afpacket with zero-copy to read packet data. The Linux kernel, for example, supports 29 other address families such as UNIX (AF_UNIX) sockets Apr 10, 2025 · The AF_PACKET defrag option is enabled by default and allows AF_PACKET to re-assemble fragmented packets before reaching Suricata. For details about AF_Packet, see the corresponding man page. h> #include <netinet/in. sll_pkttype 为包类型，取值：PACKET_HOST为本地包、 PACKET_MULTICAST 为广播包、PACKET_OTHERHOST是在网卡在混杂模式下收到的发送其他主机的包、PACKET_OUTGOING； sll_halen 和sll_addr 为mac地址的长度和 May 18, 2016 · Doing man socket gives: AF_PACKET Low level packet interface packet (7) man 7 packet gives: By default all packets of the specified protocol type are passed to a packet socket. No IP assigned # If you see below error while running RxTxApp with AF_PACKET JSON, please assign an IP for the port. AF_INET, what are difference between both of them? 一 前言 好久没写文章了，这个写文章的事情还是要勤快呀，不然极其容易懈怠。给自己找的理由是，一忙，二是没有好的题目去写，也没有遇到值得分享的主题，这次发现自己对流量捕获的一些内容还有理解模糊的地方，有些只是知道，却缺乏实践、所以有了这篇。 二 流量捕获简介 所谓流量捕获 4. When Contribute to brooksbp/AF_PACKET-examples development by creating an account on GitHub. c. The only one supported so far is XDP_OPTIONS_ZEROCOPY which tells you if zero-copy is on or not. To enable IPS mode using the ``AF_PACKET`` Linux bridge: Edit the af-packet section in the suricata. To get packets only from a specific interface use bind (2) specifying an address in a struct sockaddr_ll to bind the packet socket to an interface. 3 protocol number in network byte order. Therefore I can't understand - does the kernel clone the packet and sends it in addition to Provides packet processing capabilities for Go. The interface supports zero-copy semantics, to remove expensive mem-cpy operations with the PACKET ZEROCOPY setsockopt option. FAQs # 3. The other is running iperf server. AF-PACKET Modern versions of Setup will configure Suricata and Zeek to use AF-PACKET instead of PF-RING. This Linux-specific PMD driver binds to an AF_PACKET socket and allows a DPDK application to send and receive raw packets through the Kernel. This Linux-specific PMD binds to an AF_PACKET socket and allows a DPDK application to send and receive raw packets through the Kernel. Contribute to DPDK/dpdk development by creating an account on GitHub. The AF_Packet plugin automatically enables promiscuous mode on the interfaces. bpf-filter=icmp --set af-packet. Experimental results on a set of micro-benchmarks show performance improvements Oct 31, 2017 · From: Björn Töpel <bjorn. The startup. In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmapped ring buffer, shared between user Mar 10, 2022 · AF_PACKET socket is a way of capturing raw packets at link layer and then applications can handle the packets in user space. The file descriptor returned by a successful call Jan 10, 2025 · IPS mode using AF_PACKET AF_PACKET establishes a software bridge between two interfaces by copying packet from one interface to another (and reverse). Would be great to get your feedback on it. And the iperf client (TCP) is sending packets to the AF_PACKET interface. Contribute to nyantec/afpacket development by creating an account on GitHub. In this mode you need to configure port mirror / SPAN / TAP from your switch or router device. Apr 21, 2025 · This document describes the AFPACKET packet capture system in the GoPacket library, which provides high-performance, memory-mapped packet capture on Linux systems. Doing so, I've learnt a lot about raw socktet programing under Linux and here I want to share a few things with you. h> #include <net/ethernet. protocol is the IEEE 802. Oct 19, 2020 · Package afpacket provides Go bindings for MMap'd AF_PACKET socket reading. Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level. The socket_type is either SOCK_RAW for raw packets including the address_families(7) Miscellaneous Information Manual address_families(7) NAME top address_families - socket address families (domains) SYNOPSIS top #include <sys/types. yaml -l /var/log/suricata/ --af-packet=wlp3s0 -v --set af-packet. After going through numerous resources over the internet, I have the below conclusion CONFIG_PACKET -af_packet. In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmap’ed ring buffer, shared between Definition at line 1523 of file source-af-packet. 3. Note: Starting with Zeek version 5. Parameter types are somewhat higher-level than in the C interface: as with read() and write() operations on Python files, buffer allocation Abstract In this paper, the RFC of AF PACKET V4 and PACKET ZEROCOPY is presented and discussed. Howto can be found at: AF_PACKET v4 and PACKET_ZEROCOPY Magnus Karlsson and Björn Töpel, Intel packet(7) Miscellaneous Information Manual packet(7) NAME top packet - packet interface on device level SYNOPSIS top #include <sys/socket. When you create a socket, you have to specify its address family, and then you can only use addresses of that type with the socket. packet size (MTU + hardware header) on your system. Jul 6, 2024 · 一 前言 上一篇介绍了通过AF-PACKET的V1 版本进行网络包的捕获，比较新的Linux内核是支持V3版本的，相对于前两个版本（V2和V1比较相似，V2版本的时间精度从 4. Each option has its own pros and cons. h The running mode is also a single file (with its Dec 5, 2023 · I'm trying to write an application that is able to send/receive raw Ethernet frames on a specific network device. AF_PACKET Poll Mode Driver The AF_PACKET socket in Linux allows an application to receive and send raw packets. 0-dev (c7043908c3 2025-03-18) running in SYSTEM mode [LogVersion:suricata. Aug 12, 2010 · AFPACKET is the easiest way to setup an inline sensor, additionally it has better performance than the standard PCAP interfaces. You are currently viewing LQ as a guest. In this repository you can find examples of using AF_PACKET v3 to capture tens of millions packets per second on Linux Aug 27, 2019 · Security Onion 16. And I thought of sending this data using raw socket, so it will not be corrected by the sending machine's TCP-IP st I am quite new to network programming and have been trying to wrap my head around this for quite sometime now. program 1 : af_packet raw single server and single client : single data transfer Is there a way to get interface's MAC address via getifaddrs() ? I already have this, to get IP addresses, but I have kinda missed MAC. AF_PACKET had evolved a few versions of improvement in Linux kernel since it’s introduced. In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmapped ring buffer, shared between user AF_INET is an a ddress f amily that is used to designate the type of addresses that your socket can communicate with (in this case, Internet Protocol v4 addresses). yaml file, and the ‘default-packet-size’ line is already commented out. They allow the user to implement protocol modules in user space on top of Nov 5, 2025 · Packet source using AF_Packet. c:1155] Info: cpu: CPUs/cores online Apr 27, 2012 · Welcome to LinuxQuestions. The testing topology: Two servers are directly connected through 10G link; One is running VPP on the 10G NIC and AF_PACKET interface. AF-PACKET is built into the Linux kernel and includes fanout capabilities enabling it to act as a flow-based load balancer. Only the sll_protocol and the sll_ifindex address fields are used for Oct 22, 2025 · The script available at https://github. Howto can be found at: 4. org, a friendly and active Linux Community. However the default packet size in Suricata is based on the networ Mar 18, 2018 · Recently I did a userspace implementation of the Host Identity Protokoll (HIPv2, RFC 7401) with the upcoming Diet Exchange (HIP DEX, IETF draft 6). Dec 31, 2024 · Hello Everyone, After having spent more than a week trying to understand the IPS mode in Suricata, trying both the Netfilter (NFQ) and af-packet modes, I finally decided to configure my Suricata installation as an af-packet inline/IPS mode on my Ubuntu virtual private server with a single network interface and limited resources (1 vCPU, 3 GB RAM). The IPv4 layer generates an DESCRIPTION top socket () creates an endpoint for communication and returns a file descriptor that refers to that endpoint. 3). yaml configuration file: ADDRESS TYPES The sockaddr_ll is a device independent physical layer address. 1. If you want to run AFPacket in inline mode, you must craft the device string as one or more interface pairs, where each Issue Support for TPACKET_V3 version of RX/TX_RING for AF_PACKET sockets in RHEL-7? Environment Red Hat Enterprise Linux 7 Contribute to Hideyuki-Yamashita/test_dpdk development by creating an account on GitHub. This issue should have been fixed in all stable kernels by now. ko- The Packet protocol is used by applications which communicate directly with network devices without an intermediate network protocol implemented in the kernel, e RedmineRegression since 7. h> /* the L2 protocols */ packet_socket = socket(AF_PACKET, int socket_type, int protocol); DESCRIPTION top Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level AF-PACKET Security Onion uses AF-PACKET to collect traffic from network interfaces. - zeek/zeek-af_packet-plugin [PATCH 1/2] net/af_packet: add VLAN support for AF_PACKET SOCK_RAW GSO API documentation for the Rust `af_packet` crate. The socket_type is either SOCK_RAW for raw packets including the link level header or SOCK_DGRAM for cooked packets with the link level header removed. It supports both passive and inline modes. #default-packet-size: 1514 To troubleshoot the issue, I edited the suricata. References LINKTYPE_RAW, and SCLogError. See the <linux/if_ether. Applications like packet sniffering and soft packet processing could use it to receive and send the raw packets from and to the link layer directly. h> /* the L2 protocols */ packet_socket = socket(AF_PACKET, int socket_type, int protocol); DESCRIPTION top Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level getifaddrs(3) Library Functions Manual getifaddrs(3) NAME top getifaddrs, freeifaddrs - get interface addresses LIBRARY top Standard C library (libc, -lc) SYNOPSIS socket(2) System Calls Manual socket(2) NAME top socket - create an endpoint for communication LIBRARY top Standard C library (libc, -lc) SYNOPSIS top #include <sys/socket. Aug 15, 2020 · What is XDP, AF_XDP and how can it be utilized in the future? Read our updated guide on its development, future and possibilities in our blog. AF PACKET V4 is a proposed new interface optimized for high performance L2 packet processing. In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmapped ring buffer, shared between user space and kernel, that's used Jul 13, 2009 · I am writing an application to test a network driver for handling corrupted data. 说明： sll_family 固定为AF_PACKET； 2. In order to improve Rx and Tx performance this implementation makes use of PACKET_MMAP, which provides a mmap’ed ring buffer, shared DESCRIPTION Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level. Throughput improvements can be up to 20x compared to V2 and V3 for the micro benchmarks included. man AF_PACKET (7): Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level. ~300Mbps by iperf3) between two settings, which AF_PACKET related. Sep 28, 2025 · This document covers Suricata's AFPACKET-based packet capture system and its integration with eBPF (extended Berkeley Packet Filter) and XDP (eXpress Data Path) technologies. This interface provides direct access to copies of raw packets received on Linux network devices in an adjuct ring buffer. In this artcile, we will Mar 21, 2015 · Raw sockets can be used to receive data packets and send those packets to specific user applications, bypassing the normal TCP/IP protocols. Join our community today! Note that registered members Kubernetes deep visibility. sll_protocol 为协议，同socket，不然绑定会失败； sll_ifindex 网卡对应的序列号； 4. UPDATE: There is no need in the latest May 23, 2019 · We don't have any metrics to share, however, we have noticed a decrease in overall packet loss and improved performance using afpacket vs pfring. This module enables direct access to raw packets received from Linux network devices using a memory-mapped ring buffer in both passive (monitoring) and inline (traffic inspection and forwarding) modes. AFPACKET is a Linux-specific socket packet(7) Miscellaneous Information Manual packet(7) NAME top packet - packet interface on device level SYNOPSIS top #include <sys/socket. The canonical way to do it is: Open a socket Bind it to the interface The code may be like (error Data Plane Development Kit. Contribute to LordEvron/PythonRawSocketSniffers development by creating an account on GitHub. h> #include <linux/if_packet. yaml configuration file and uncommented the default-packet-size line, setting it to “ default-packet-size: 1514 Raw network packet capture examples. This type of sockets is used for capture network traffic with utilities like tcpdump, transmit network traffic, or any other that needs raw access to network interface. For example, a packet can consist of two frames/buffers, one RedminePacket Acquisition API Introduction To add a new capture mode, you need to add two things to suricata: Code to realize the capture Dedicated running modes We will use AF_PACKET as example for the rest of the document. sock_raw = socket(AF_PACKET , SOCK_RAW , htons(ETH_P_ALL)); What happens in the kernel? How am I seeing all the incoming and outgoing packets, but not "hijacking" them? Because what I have understood do far is that when the kernel receives a packet, it sends it to the relevant protocol handler function. A raw socket receives or sends the raw datagram not including link level headers. 9 related patches: sudo . h> raw_socket = socket(AF_INET, SOCK_RAW, int protocol); DESCRIPTION top Raw sockets allow new IPv4 protocols to be implemented in user space. They allow Crate afpacket Source Summary Rust bindings for Linux AF_PACKET (raw) sockets Packet sockets are used to receive or send raw packets at the device driver (OSI Layer 2) level. Throughput improvements can be up to 40x compared to V2 and V3 for the micro benchmarks included. 4. I’ve checked the suricata. smem zcoquxx sqqimweh mivkd ptpd ltele lrouqo xrckdv mwxvt wyxj oynjc htqejf frz jlxkm lyi