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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /samples/bpf/cookie_uid_helper_example.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'samples/bpf/cookie_uid_helper_example.c')
-rw-r--r--samples/bpf/cookie_uid_helper_example.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c
new file mode 100644
index 000000000..f0df3dda4
--- /dev/null
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -0,0 +1,332 @@
+/* This test is a demo of using get_socket_uid and get_socket_cookie
+ * helper function to do per socket based network traffic monitoring.
+ * It requires iptables version higher then 1.6.1. to load pinned eBPF
+ * program into the xt_bpf match.
+ *
+ * TEST:
+ * ./run_cookie_uid_helper_example.sh -option
+ * option:
+ * -t: do traffic monitoring test, the program will continuously
+ * print out network traffic happens after program started A sample
+ * output is shown below:
+ *
+ * cookie: 877, uid: 0x3e8, Pakcet Count: 20, Bytes Count: 11058
+ * cookie: 132, uid: 0x0, Pakcet Count: 2, Bytes Count: 286
+ * cookie: 812, uid: 0x3e8, Pakcet Count: 3, Bytes Count: 1726
+ * cookie: 802, uid: 0x3e8, Pakcet Count: 2, Bytes Count: 104
+ * cookie: 877, uid: 0x3e8, Pakcet Count: 20, Bytes Count: 11058
+ * cookie: 831, uid: 0x3e8, Pakcet Count: 2, Bytes Count: 104
+ * cookie: 0, uid: 0x0, Pakcet Count: 6, Bytes Count: 712
+ * cookie: 880, uid: 0xfffe, Pakcet Count: 1, Bytes Count: 70
+ *
+ * -s: do getsockopt SO_COOKIE test, the program will set up a pair of
+ * UDP sockets and send packets between them. And read out the traffic data
+ * directly from the ebpf map based on the socket cookie.
+ *
+ * Clean up: if using shell script, the script file will delete the iptables
+ * rule and unmount the bpf program when exit. Else the iptables rule need
+ * to be deleted by hand, see run_cookie_uid_helper_example.sh for detail.
+ */
+
+#define _GNU_SOURCE
+
+#define offsetof(type, member) __builtin_offsetof(type, member)
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <error.h>
+#include <limits.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <net/if.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <bpf/bpf.h>
+#include "bpf_insn.h"
+
+#define PORT 8888
+
+struct stats {
+ uint32_t uid;
+ uint64_t packets;
+ uint64_t bytes;
+};
+
+static int map_fd, prog_fd;
+
+static bool test_finish;
+
+static void maps_create(void)
+{
+ map_fd = bpf_map_create(BPF_MAP_TYPE_HASH, NULL, sizeof(uint32_t),
+ sizeof(struct stats), 100, NULL);
+ if (map_fd < 0)
+ error(1, errno, "map create failed!\n");
+}
+
+static void prog_load(void)
+{
+ static char log_buf[1 << 16];
+
+ struct bpf_insn prog[] = {
+ /*
+ * Save sk_buff for future usage. value stored in R6 to R10 will
+ * not be reset after a bpf helper function call.
+ */
+ BPF_MOV64_REG(BPF_REG_6, BPF_REG_1),
+ /*
+ * pc1: BPF_FUNC_get_socket_cookie takes one parameter,
+ * R1: sk_buff
+ */
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_socket_cookie),
+ /* pc2-4: save &socketCookie to r7 for future usage*/
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
+ BPF_MOV64_REG(BPF_REG_7, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, -8),
+ /*
+ * pc5-8: set up the registers for BPF_FUNC_map_lookup_elem,
+ * it takes two parameters (R1: map_fd, R2: &socket_cookie)
+ */
+ BPF_LD_MAP_FD(BPF_REG_1, map_fd),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_map_lookup_elem),
+ /*
+ * pc9. if r0 != 0x0, go to pc+14, since we have the cookie
+ * stored already
+ * Otherwise do pc10-22 to setup a new data entry.
+ */
+ BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 14),
+ BPF_MOV64_REG(BPF_REG_1, BPF_REG_6),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_get_socket_uid),
+ /*
+ * Place a struct stats in the R10 stack and sequentially
+ * place the member value into the memory. Packets value
+ * is set by directly place a IMM value 1 into the stack.
+ */
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0,
+ -32 + (__s16)offsetof(struct stats, uid)),
+ BPF_ST_MEM(BPF_DW, BPF_REG_10,
+ -32 + (__s16)offsetof(struct stats, packets), 1),
+ /*
+ * __sk_buff is a special struct used for eBPF program to
+ * directly access some sk_buff field.
+ */
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6,
+ offsetof(struct __sk_buff, len)),
+ BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_1,
+ -32 + (__s16)offsetof(struct stats, bytes)),
+ /*
+ * add new map entry using BPF_FUNC_map_update_elem, it takes
+ * 4 parameters (R1: map_fd, R2: &socket_cookie, R3: &stats,
+ * R4: flags)
+ */
+ BPF_LD_MAP_FD(BPF_REG_1, map_fd),
+ BPF_MOV64_REG(BPF_REG_2, BPF_REG_7),
+ BPF_MOV64_REG(BPF_REG_3, BPF_REG_10),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -32),
+ BPF_MOV64_IMM(BPF_REG_4, 0),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ BPF_FUNC_map_update_elem),
+ BPF_JMP_IMM(BPF_JA, 0, 0, 5),
+ /*
+ * pc24-30 update the packet info to a exist data entry, it can
+ * be done by directly write to pointers instead of using
+ * BPF_FUNC_map_update_elem helper function
+ */
+ BPF_MOV64_REG(BPF_REG_9, BPF_REG_0),
+ BPF_MOV64_IMM(BPF_REG_1, 1),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_9, BPF_REG_1,
+ offsetof(struct stats, packets)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_6,
+ offsetof(struct __sk_buff, len)),
+ BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_9, BPF_REG_1,
+ offsetof(struct stats, bytes)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6,
+ offsetof(struct __sk_buff, len)),
+ BPF_EXIT_INSN(),
+ };
+ LIBBPF_OPTS(bpf_prog_load_opts, opts,
+ .log_buf = log_buf,
+ .log_size = sizeof(log_buf),
+ );
+
+ prog_fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL",
+ prog, ARRAY_SIZE(prog), &opts);
+ if (prog_fd < 0)
+ error(1, errno, "failed to load prog\n%s\n", log_buf);
+}
+
+static void prog_attach_iptables(char *file)
+{
+ int ret;
+ char rules[256];
+
+ if (bpf_obj_pin(prog_fd, file))
+ error(1, errno, "bpf_obj_pin");
+ if (strlen(file) > 50) {
+ printf("file path too long: %s\n", file);
+ exit(1);
+ }
+ ret = snprintf(rules, sizeof(rules),
+ "iptables -A OUTPUT -m bpf --object-pinned %s -j ACCEPT",
+ file);
+ if (ret < 0 || ret >= sizeof(rules)) {
+ printf("error constructing iptables command\n");
+ exit(1);
+ }
+ ret = system(rules);
+ if (ret < 0) {
+ printf("iptables rule update failed: %d/n", WEXITSTATUS(ret));
+ exit(1);
+ }
+}
+
+static void print_table(void)
+{
+ struct stats curEntry;
+ uint32_t curN = UINT32_MAX;
+ uint32_t nextN;
+ int res;
+
+ while (bpf_map_get_next_key(map_fd, &curN, &nextN) > -1) {
+ curN = nextN;
+ res = bpf_map_lookup_elem(map_fd, &curN, &curEntry);
+ if (res < 0) {
+ error(1, errno, "fail to get entry value of Key: %u\n",
+ curN);
+ } else {
+ printf("cookie: %u, uid: 0x%x, Packet Count: %lu,"
+ " Bytes Count: %lu\n", curN, curEntry.uid,
+ curEntry.packets, curEntry.bytes);
+ }
+ }
+}
+
+static void udp_client(void)
+{
+ struct sockaddr_in si_other = {0};
+ struct sockaddr_in si_me = {0};
+ struct stats dataEntry;
+ int s_rcv, s_send, i, recv_len;
+ char message = 'a';
+ char buf;
+ uint64_t cookie;
+ int res;
+ socklen_t cookie_len = sizeof(cookie);
+ socklen_t slen = sizeof(si_other);
+
+ s_rcv = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s_rcv < 0)
+ error(1, errno, "rcv socket creat failed!\n");
+ si_other.sin_family = AF_INET;
+ si_other.sin_port = htons(PORT);
+ if (inet_aton("127.0.0.1", &si_other.sin_addr) == 0)
+ error(1, errno, "inet_aton\n");
+ if (bind(s_rcv, (struct sockaddr *)&si_other, sizeof(si_other)) == -1)
+ error(1, errno, "bind\n");
+ s_send = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s_send < 0)
+ error(1, errno, "send socket creat failed!\n");
+ res = getsockopt(s_send, SOL_SOCKET, SO_COOKIE, &cookie, &cookie_len);
+ if (res < 0)
+ printf("get cookie failed: %s\n", strerror(errno));
+ res = bpf_map_lookup_elem(map_fd, &cookie, &dataEntry);
+ if (res != -1)
+ error(1, errno, "socket stat found while flow not active\n");
+ for (i = 0; i < 10; i++) {
+ res = sendto(s_send, &message, sizeof(message), 0,
+ (struct sockaddr *)&si_other, slen);
+ if (res == -1)
+ error(1, errno, "send\n");
+ if (res != sizeof(message))
+ error(1, 0, "%uB != %luB\n", res, sizeof(message));
+ recv_len = recvfrom(s_rcv, &buf, sizeof(buf), 0,
+ (struct sockaddr *)&si_me, &slen);
+ if (recv_len < 0)
+ error(1, errno, "receive\n");
+ res = memcmp(&(si_other.sin_addr), &(si_me.sin_addr),
+ sizeof(si_me.sin_addr));
+ if (res != 0)
+ error(1, EFAULT, "sender addr error: %d\n", res);
+ printf("Message received: %c\n", buf);
+ res = bpf_map_lookup_elem(map_fd, &cookie, &dataEntry);
+ if (res < 0)
+ error(1, errno, "lookup sk stat failed, cookie: %lu\n",
+ cookie);
+ printf("cookie: %lu, uid: 0x%x, Packet Count: %lu,"
+ " Bytes Count: %lu\n\n", cookie, dataEntry.uid,
+ dataEntry.packets, dataEntry.bytes);
+ }
+ close(s_send);
+ close(s_rcv);
+}
+
+static int usage(void)
+{
+ printf("Usage: ./run_cookie_uid_helper_example.sh"
+ " bpfObjName -option\n"
+ " -t traffic monitor test\n"
+ " -s getsockopt cookie test\n");
+ return 1;
+}
+
+static void finish(int ret)
+{
+ test_finish = true;
+}
+
+int main(int argc, char *argv[])
+{
+ int opt;
+ bool cfg_test_traffic = false;
+ bool cfg_test_cookie = false;
+
+ if (argc != 3)
+ return usage();
+ while ((opt = getopt(argc, argv, "ts")) != -1) {
+ switch (opt) {
+ case 't':
+ cfg_test_traffic = true;
+ break;
+ case 's':
+ cfg_test_cookie = true;
+ break;
+
+ default:
+ printf("unknown option %c\n", opt);
+ usage();
+ return -1;
+ }
+ }
+ maps_create();
+ prog_load();
+ prog_attach_iptables(argv[2]);
+ if (cfg_test_traffic) {
+ if (signal(SIGINT, finish) == SIG_ERR)
+ error(1, errno, "register SIGINT handler failed");
+ if (signal(SIGTERM, finish) == SIG_ERR)
+ error(1, errno, "register SIGTERM handler failed");
+ while (!test_finish) {
+ print_table();
+ printf("\n");
+ sleep(1);
+ }
+ } else if (cfg_test_cookie) {
+ udp_client();
+ }
+ close(prog_fd);
+ close(map_fd);
+ return 0;
+}