diff options
Diffstat (limited to 'samples/bpf/xdp_router_ipv4_user.c')
| -rw-r--r-- | samples/bpf/xdp_router_ipv4_user.c | 699 |
1 files changed, 699 insertions, 0 deletions
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c new file mode 100644 index 0000000000..9d41db09c4 --- /dev/null +++ b/samples/bpf/xdp_router_ipv4_user.c @@ -0,0 +1,699 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2017 Cavium, Inc. + */ +#include <linux/bpf.h> +#include <linux/netlink.h> +#include <linux/rtnetlink.h> +#include <assert.h> +#include <errno.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/socket.h> +#include <unistd.h> +#include <bpf/bpf.h> +#include <arpa/inet.h> +#include <fcntl.h> +#include <poll.h> +#include <net/if.h> +#include <netdb.h> +#include <sys/ioctl.h> +#include <sys/syscall.h> +#include "bpf_util.h" +#include <bpf/libbpf.h> +#include <libgen.h> +#include <getopt.h> +#include <pthread.h> +#include "xdp_sample_user.h" +#include "xdp_router_ipv4.skel.h" + +static const char *__doc__ = +"XDP IPv4 router implementation\n" +"Usage: xdp_router_ipv4 <IFNAME-0> ... <IFNAME-N>\n"; + +static char buf[8192]; +static int lpm_map_fd; +static int arp_table_map_fd; +static int exact_match_map_fd; +static int tx_port_map_fd; + +static bool routes_thread_exit; +static int interval = 5; + +static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_MAP_CNT | + SAMPLE_DEVMAP_XMIT_CNT_MULTI | SAMPLE_EXCEPTION_CNT; + +DEFINE_SAMPLE_INIT(xdp_router_ipv4); + +static const struct option long_options[] = { + { "help", no_argument, NULL, 'h' }, + { "skb-mode", no_argument, NULL, 'S' }, + { "force", no_argument, NULL, 'F' }, + { "interval", required_argument, NULL, 'i' }, + { "verbose", no_argument, NULL, 'v' }, + { "stats", no_argument, NULL, 's' }, + {} +}; + +static int get_route_table(int rtm_family); + +static int recv_msg(struct sockaddr_nl sock_addr, int sock) +{ + struct nlmsghdr *nh; + int len, nll = 0; + char *buf_ptr; + + buf_ptr = buf; + while (1) { + len = recv(sock, buf_ptr, sizeof(buf) - nll, 0); + if (len < 0) + return len; + + nh = (struct nlmsghdr *)buf_ptr; + + if (nh->nlmsg_type == NLMSG_DONE) + break; + buf_ptr += len; + nll += len; + if ((sock_addr.nl_groups & RTMGRP_NEIGH) == RTMGRP_NEIGH) + break; + + if ((sock_addr.nl_groups & RTMGRP_IPV4_ROUTE) == RTMGRP_IPV4_ROUTE) + break; + } + return nll; +} + +/* Function to parse the route entry returned by netlink + * Updates the route entry related map entries + */ +static void read_route(struct nlmsghdr *nh, int nll) +{ + char dsts[24], gws[24], ifs[16], dsts_len[24], metrics[24]; + struct bpf_lpm_trie_key *prefix_key; + struct rtattr *rt_attr; + struct rtmsg *rt_msg; + int rtm_family; + int rtl; + int i; + struct route_table { + int dst_len, iface, metric; + __be32 dst, gw; + __be64 mac; + } route; + struct arp_table { + __be64 mac; + __be32 dst; + }; + + struct direct_map { + struct arp_table arp; + int ifindex; + __be64 mac; + } direct_entry; + + memset(&route, 0, sizeof(route)); + for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) { + rt_msg = (struct rtmsg *)NLMSG_DATA(nh); + rtm_family = rt_msg->rtm_family; + if (rtm_family == AF_INET) + if (rt_msg->rtm_table != RT_TABLE_MAIN) + continue; + rt_attr = (struct rtattr *)RTM_RTA(rt_msg); + rtl = RTM_PAYLOAD(nh); + + for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) { + switch (rt_attr->rta_type) { + case NDA_DST: + sprintf(dsts, "%u", + (*((__be32 *)RTA_DATA(rt_attr)))); + break; + case RTA_GATEWAY: + sprintf(gws, "%u", + *((__be32 *)RTA_DATA(rt_attr))); + break; + case RTA_OIF: + sprintf(ifs, "%u", + *((int *)RTA_DATA(rt_attr))); + break; + case RTA_METRICS: + sprintf(metrics, "%u", + *((int *)RTA_DATA(rt_attr))); + default: + break; + } + } + sprintf(dsts_len, "%d", rt_msg->rtm_dst_len); + route.dst = atoi(dsts); + route.dst_len = atoi(dsts_len); + route.gw = atoi(gws); + route.iface = atoi(ifs); + route.metric = atoi(metrics); + assert(get_mac_addr(route.iface, &route.mac) == 0); + assert(bpf_map_update_elem(tx_port_map_fd, + &route.iface, &route.iface, 0) == 0); + if (rtm_family == AF_INET) { + struct trie_value { + __u8 prefix[4]; + __be64 value; + int ifindex; + int metric; + __be32 gw; + } *prefix_value; + + prefix_key = alloca(sizeof(*prefix_key) + 4); + prefix_value = alloca(sizeof(*prefix_value)); + + prefix_key->prefixlen = 32; + prefix_key->prefixlen = route.dst_len; + direct_entry.mac = route.mac & 0xffffffffffff; + direct_entry.ifindex = route.iface; + direct_entry.arp.mac = 0; + direct_entry.arp.dst = 0; + if (route.dst_len == 32) { + if (nh->nlmsg_type == RTM_DELROUTE) { + assert(bpf_map_delete_elem(exact_match_map_fd, + &route.dst) == 0); + } else { + if (bpf_map_lookup_elem(arp_table_map_fd, + &route.dst, + &direct_entry.arp.mac) == 0) + direct_entry.arp.dst = route.dst; + assert(bpf_map_update_elem(exact_match_map_fd, + &route.dst, + &direct_entry, 0) == 0); + } + } + for (i = 0; i < 4; i++) + prefix_key->data[i] = (route.dst >> i * 8) & 0xff; + + if (bpf_map_lookup_elem(lpm_map_fd, prefix_key, + prefix_value) < 0) { + for (i = 0; i < 4; i++) + prefix_value->prefix[i] = prefix_key->data[i]; + prefix_value->value = route.mac & 0xffffffffffff; + prefix_value->ifindex = route.iface; + prefix_value->gw = route.gw; + prefix_value->metric = route.metric; + + assert(bpf_map_update_elem(lpm_map_fd, + prefix_key, + prefix_value, 0 + ) == 0); + } else { + if (nh->nlmsg_type == RTM_DELROUTE) { + assert(bpf_map_delete_elem(lpm_map_fd, + prefix_key + ) == 0); + /* Rereading the route table to check if + * there is an entry with the same + * prefix but a different metric as the + * deleted entry. + */ + get_route_table(AF_INET); + } else if (prefix_key->data[0] == + prefix_value->prefix[0] && + prefix_key->data[1] == + prefix_value->prefix[1] && + prefix_key->data[2] == + prefix_value->prefix[2] && + prefix_key->data[3] == + prefix_value->prefix[3] && + route.metric >= prefix_value->metric) { + continue; + } else { + for (i = 0; i < 4; i++) + prefix_value->prefix[i] = + prefix_key->data[i]; + prefix_value->value = + route.mac & 0xffffffffffff; + prefix_value->ifindex = route.iface; + prefix_value->gw = route.gw; + prefix_value->metric = route.metric; + assert(bpf_map_update_elem(lpm_map_fd, + prefix_key, + prefix_value, + 0) == 0); + } + } + } + memset(&route, 0, sizeof(route)); + memset(dsts, 0, sizeof(dsts)); + memset(dsts_len, 0, sizeof(dsts_len)); + memset(gws, 0, sizeof(gws)); + memset(ifs, 0, sizeof(ifs)); + memset(&route, 0, sizeof(route)); + } +} + +/* Function to read the existing route table when the process is launched*/ +static int get_route_table(int rtm_family) +{ + struct sockaddr_nl sa; + struct nlmsghdr *nh; + int sock, seq = 0; + struct msghdr msg; + struct iovec iov; + int ret = 0; + int nll; + + struct { + struct nlmsghdr nl; + struct rtmsg rt; + char buf[8192]; + } req; + + sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock < 0) { + fprintf(stderr, "open netlink socket: %s\n", strerror(errno)); + return -errno; + } + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) { + fprintf(stderr, "bind netlink socket: %s\n", strerror(errno)); + ret = -errno; + goto cleanup; + } + memset(&req, 0, sizeof(req)); + req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)); + req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; + req.nl.nlmsg_type = RTM_GETROUTE; + + req.rt.rtm_family = rtm_family; + req.rt.rtm_table = RT_TABLE_MAIN; + req.nl.nlmsg_pid = 0; + req.nl.nlmsg_seq = ++seq; + memset(&msg, 0, sizeof(msg)); + iov.iov_base = (void *)&req.nl; + iov.iov_len = req.nl.nlmsg_len; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + ret = sendmsg(sock, &msg, 0); + if (ret < 0) { + fprintf(stderr, "send to netlink: %s\n", strerror(errno)); + ret = -errno; + goto cleanup; + } + memset(buf, 0, sizeof(buf)); + nll = recv_msg(sa, sock); + if (nll < 0) { + fprintf(stderr, "recv from netlink: %s\n", strerror(nll)); + ret = nll; + goto cleanup; + } + nh = (struct nlmsghdr *)buf; + read_route(nh, nll); +cleanup: + close(sock); + return ret; +} + +/* Function to parse the arp entry returned by netlink + * Updates the arp entry related map entries + */ +static void read_arp(struct nlmsghdr *nh, int nll) +{ + struct rtattr *rt_attr; + char dsts[24], mac[24]; + struct ndmsg *rt_msg; + int rtl, ndm_family; + + struct arp_table { + __be64 mac; + __be32 dst; + } arp_entry; + struct direct_map { + struct arp_table arp; + int ifindex; + __be64 mac; + } direct_entry; + + for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) { + rt_msg = (struct ndmsg *)NLMSG_DATA(nh); + rt_attr = (struct rtattr *)RTM_RTA(rt_msg); + ndm_family = rt_msg->ndm_family; + rtl = RTM_PAYLOAD(nh); + for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) { + switch (rt_attr->rta_type) { + case NDA_DST: + sprintf(dsts, "%u", + *((__be32 *)RTA_DATA(rt_attr))); + break; + case NDA_LLADDR: + sprintf(mac, "%lld", + *((__be64 *)RTA_DATA(rt_attr))); + break; + default: + break; + } + } + arp_entry.dst = atoi(dsts); + arp_entry.mac = atol(mac); + + if (ndm_family == AF_INET) { + if (bpf_map_lookup_elem(exact_match_map_fd, + &arp_entry.dst, + &direct_entry) == 0) { + if (nh->nlmsg_type == RTM_DELNEIGH) { + direct_entry.arp.dst = 0; + direct_entry.arp.mac = 0; + } else if (nh->nlmsg_type == RTM_NEWNEIGH) { + direct_entry.arp.dst = arp_entry.dst; + direct_entry.arp.mac = arp_entry.mac; + } + assert(bpf_map_update_elem(exact_match_map_fd, + &arp_entry.dst, + &direct_entry, 0 + ) == 0); + memset(&direct_entry, 0, sizeof(direct_entry)); + } + if (nh->nlmsg_type == RTM_DELNEIGH) { + assert(bpf_map_delete_elem(arp_table_map_fd, + &arp_entry.dst) == 0); + } else if (nh->nlmsg_type == RTM_NEWNEIGH) { + assert(bpf_map_update_elem(arp_table_map_fd, + &arp_entry.dst, + &arp_entry.mac, 0 + ) == 0); + } + } + memset(&arp_entry, 0, sizeof(arp_entry)); + memset(dsts, 0, sizeof(dsts)); + } +} + +/* Function to read the existing arp table when the process is launched*/ +static int get_arp_table(int rtm_family) +{ + struct sockaddr_nl sa; + struct nlmsghdr *nh; + int sock, seq = 0; + struct msghdr msg; + struct iovec iov; + int ret = 0; + int nll; + struct { + struct nlmsghdr nl; + struct ndmsg rt; + char buf[8192]; + } req; + + sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock < 0) { + fprintf(stderr, "open netlink socket: %s\n", strerror(errno)); + return -errno; + } + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) { + fprintf(stderr, "bind netlink socket: %s\n", strerror(errno)); + ret = -errno; + goto cleanup; + } + memset(&req, 0, sizeof(req)); + req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg)); + req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP; + req.nl.nlmsg_type = RTM_GETNEIGH; + req.rt.ndm_state = NUD_REACHABLE; + req.rt.ndm_family = rtm_family; + req.nl.nlmsg_pid = 0; + req.nl.nlmsg_seq = ++seq; + memset(&msg, 0, sizeof(msg)); + iov.iov_base = (void *)&req.nl; + iov.iov_len = req.nl.nlmsg_len; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + ret = sendmsg(sock, &msg, 0); + if (ret < 0) { + fprintf(stderr, "send to netlink: %s\n", strerror(errno)); + ret = -errno; + goto cleanup; + } + memset(buf, 0, sizeof(buf)); + nll = recv_msg(sa, sock); + if (nll < 0) { + fprintf(stderr, "recv from netlink: %s\n", strerror(nll)); + ret = nll; + goto cleanup; + } + nh = (struct nlmsghdr *)buf; + read_arp(nh, nll); +cleanup: + close(sock); + return ret; +} + +/* Function to keep track and update changes in route and arp table + * Give regular statistics of packets forwarded + */ +static void *monitor_routes_thread(void *arg) +{ + struct pollfd fds_route, fds_arp; + struct sockaddr_nl la, lr; + int sock, sock_arp, nll; + struct nlmsghdr *nh; + + sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock < 0) { + fprintf(stderr, "open netlink socket: %s\n", strerror(errno)); + return NULL; + } + + fcntl(sock, F_SETFL, O_NONBLOCK); + memset(&lr, 0, sizeof(lr)); + lr.nl_family = AF_NETLINK; + lr.nl_groups = RTMGRP_IPV6_ROUTE | RTMGRP_IPV4_ROUTE | RTMGRP_NOTIFY; + if (bind(sock, (struct sockaddr *)&lr, sizeof(lr)) < 0) { + fprintf(stderr, "bind netlink socket: %s\n", strerror(errno)); + close(sock); + return NULL; + } + + fds_route.fd = sock; + fds_route.events = POLL_IN; + + sock_arp = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); + if (sock_arp < 0) { + fprintf(stderr, "open netlink socket: %s\n", strerror(errno)); + close(sock); + return NULL; + } + + fcntl(sock_arp, F_SETFL, O_NONBLOCK); + memset(&la, 0, sizeof(la)); + la.nl_family = AF_NETLINK; + la.nl_groups = RTMGRP_NEIGH | RTMGRP_NOTIFY; + if (bind(sock_arp, (struct sockaddr *)&la, sizeof(la)) < 0) { + fprintf(stderr, "bind netlink socket: %s\n", strerror(errno)); + goto cleanup; + } + + fds_arp.fd = sock_arp; + fds_arp.events = POLL_IN; + + /* dump route and arp tables */ + if (get_arp_table(AF_INET) < 0) { + fprintf(stderr, "Failed reading arp table\n"); + goto cleanup; + } + + if (get_route_table(AF_INET) < 0) { + fprintf(stderr, "Failed reading route table\n"); + goto cleanup; + } + + while (!routes_thread_exit) { + memset(buf, 0, sizeof(buf)); + if (poll(&fds_route, 1, 3) == POLL_IN) { + nll = recv_msg(lr, sock); + if (nll < 0) { + fprintf(stderr, "recv from netlink: %s\n", + strerror(nll)); + goto cleanup; + } + + nh = (struct nlmsghdr *)buf; + read_route(nh, nll); + } + + memset(buf, 0, sizeof(buf)); + if (poll(&fds_arp, 1, 3) == POLL_IN) { + nll = recv_msg(la, sock_arp); + if (nll < 0) { + fprintf(stderr, "recv from netlink: %s\n", + strerror(nll)); + goto cleanup; + } + + nh = (struct nlmsghdr *)buf; + read_arp(nh, nll); + } + + sleep(interval); + } + +cleanup: + close(sock_arp); + close(sock); + return NULL; +} + +static void usage(char *argv[], const struct option *long_options, + const char *doc, int mask, bool error, + struct bpf_object *obj) +{ + sample_usage(argv, long_options, doc, mask, error); +} + +int main(int argc, char **argv) +{ + bool error = true, generic = false, force = false; + int opt, ret = EXIT_FAIL_BPF; + struct xdp_router_ipv4 *skel; + int i, total_ifindex = argc - 1; + char **ifname_list = argv + 1; + pthread_t routes_thread; + int longindex = 0; + + if (libbpf_set_strict_mode(LIBBPF_STRICT_ALL) < 0) { + fprintf(stderr, "Failed to set libbpf strict mode: %s\n", + strerror(errno)); + goto end; + } + + skel = xdp_router_ipv4__open(); + if (!skel) { + fprintf(stderr, "Failed to xdp_router_ipv4__open: %s\n", + strerror(errno)); + goto end; + } + + ret = sample_init_pre_load(skel); + if (ret < 0) { + fprintf(stderr, "Failed to sample_init_pre_load: %s\n", + strerror(-ret)); + ret = EXIT_FAIL_BPF; + goto end_destroy; + } + + ret = xdp_router_ipv4__load(skel); + if (ret < 0) { + fprintf(stderr, "Failed to xdp_router_ipv4__load: %s\n", + strerror(errno)); + goto end_destroy; + } + + ret = sample_init(skel, mask); + if (ret < 0) { + fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret)); + ret = EXIT_FAIL; + goto end_destroy; + } + + while ((opt = getopt_long(argc, argv, "si:SFvh", + long_options, &longindex)) != -1) { + switch (opt) { + case 's': + mask |= SAMPLE_REDIRECT_MAP_CNT; + total_ifindex--; + ifname_list++; + break; + case 'i': + interval = strtoul(optarg, NULL, 0); + total_ifindex -= 2; + ifname_list += 2; + break; + case 'S': + generic = true; + total_ifindex--; + ifname_list++; + break; + case 'F': + force = true; + total_ifindex--; + ifname_list++; + break; + case 'v': + sample_switch_mode(); + total_ifindex--; + ifname_list++; + break; + case 'h': + error = false; + default: + usage(argv, long_options, __doc__, mask, error, skel->obj); + goto end_destroy; + } + } + + ret = EXIT_FAIL_OPTION; + if (optind == argc) { + usage(argv, long_options, __doc__, mask, true, skel->obj); + goto end_destroy; + } + + lpm_map_fd = bpf_map__fd(skel->maps.lpm_map); + if (lpm_map_fd < 0) { + fprintf(stderr, "Failed loading lpm_map %s\n", + strerror(-lpm_map_fd)); + goto end_destroy; + } + arp_table_map_fd = bpf_map__fd(skel->maps.arp_table); + if (arp_table_map_fd < 0) { + fprintf(stderr, "Failed loading arp_table_map_fd %s\n", + strerror(-arp_table_map_fd)); + goto end_destroy; + } + exact_match_map_fd = bpf_map__fd(skel->maps.exact_match); + if (exact_match_map_fd < 0) { + fprintf(stderr, "Failed loading exact_match_map_fd %s\n", + strerror(-exact_match_map_fd)); + goto end_destroy; + } + tx_port_map_fd = bpf_map__fd(skel->maps.tx_port); + if (tx_port_map_fd < 0) { + fprintf(stderr, "Failed loading tx_port_map_fd %s\n", + strerror(-tx_port_map_fd)); + goto end_destroy; + } + + ret = EXIT_FAIL_XDP; + for (i = 0; i < total_ifindex; i++) { + int index = if_nametoindex(ifname_list[i]); + + if (!index) { + fprintf(stderr, "Interface %s not found %s\n", + ifname_list[i], strerror(-tx_port_map_fd)); + goto end_destroy; + } + if (sample_install_xdp(skel->progs.xdp_router_ipv4_prog, + index, generic, force) < 0) + goto end_destroy; + } + + ret = pthread_create(&routes_thread, NULL, monitor_routes_thread, NULL); + if (ret) { + fprintf(stderr, "Failed creating routes_thread: %s\n", strerror(-ret)); + ret = EXIT_FAIL; + goto end_destroy; + } + + ret = sample_run(interval, NULL, NULL); + routes_thread_exit = true; + + if (ret < 0) { + fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret)); + ret = EXIT_FAIL; + goto end_thread_wait; + } + ret = EXIT_OK; + +end_thread_wait: + pthread_join(routes_thread, NULL); +end_destroy: + xdp_router_ipv4__destroy(skel); +end: + sample_exit(ret); +} |