diff options
| -rw-r--r-- | tools/testing/selftests/net/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/net/Makefile | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/net/reuseport_bpf.c | 467 |
3 files changed, 469 insertions, 1 deletions
diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 0032662..6fb2336 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -1,3 +1,4 @@ socket psock_fanout psock_tpacket +reuseport_bpf diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index fac4782..41449b5 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -4,7 +4,7 @@ CFLAGS = -Wall -O2 -g CFLAGS += -I../../../../usr/include/ -NET_PROGS = socket psock_fanout psock_tpacket +NET_PROGS = socket psock_fanout psock_tpacket reuseport_bpf all: $(NET_PROGS) %: %.c diff --git a/tools/testing/selftests/net/reuseport_bpf.c b/tools/testing/selftests/net/reuseport_bpf.c new file mode 100644 index 0000000..74ff099 --- /dev/null +++ b/tools/testing/selftests/net/reuseport_bpf.c @@ -0,0 +1,467 @@ +/* + * Test functionality of BPF filters for SO_REUSEPORT. The tests below will use + * a BPF program (both classic and extended) to read the first word from an + * incoming packet (expected to be in network byte-order), calculate a modulus + * of that number, and then dispatch the packet to the Nth socket using the + * result. These tests are run for each supported address family and protocol. + * Additionally, a few edge cases in the implementation are tested. + */ + +#include <errno.h> +#include <error.h> +#include <linux/bpf.h> +#include <linux/filter.h> +#include <linux/unistd.h> +#include <netinet/in.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/epoll.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <unistd.h> + +#ifndef ARRAY_SIZE +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) +#endif + +struct test_params { + int recv_family; + int send_family; + int protocol; + size_t recv_socks; + uint16_t recv_port; + uint16_t send_port_min; +}; + +static size_t sockaddr_size(void) +{ + return sizeof(struct sockaddr_storage); +} + +static struct sockaddr *new_any_sockaddr(int family, uint16_t port) +{ + struct sockaddr_storage *addr; + struct sockaddr_in *addr4; + struct sockaddr_in6 *addr6; + + addr = malloc(sizeof(struct sockaddr_storage)); + memset(addr, 0, sizeof(struct sockaddr_storage)); + + switch (family) { + case AF_INET: + addr4 = (struct sockaddr_in *)addr; + addr4->sin_family = AF_INET; + addr4->sin_addr.s_addr = htonl(INADDR_ANY); + addr4->sin_port = htons(port); + break; + case AF_INET6: + addr6 = (struct sockaddr_in6 *)addr; + addr6->sin6_family = AF_INET6; + addr6->sin6_addr = in6addr_any; + addr6->sin6_port = htons(port); + break; + default: + error(1, 0, "Unsupported family %d", family); + } + return (struct sockaddr *)addr; +} + +static struct sockaddr *new_loopback_sockaddr(int family, uint16_t port) +{ + struct sockaddr *addr = new_any_sockaddr(family, port); + struct sockaddr_in *addr4; + struct sockaddr_in6 *addr6; + + switch (family) { + case AF_INET: + addr4 = (struct sockaddr_in *)addr; + addr4->sin_addr.s_addr = htonl(INADDR_LOOPBACK); + break; + case AF_INET6: + addr6 = (struct sockaddr_in6 *)addr; + addr6->sin6_addr = in6addr_loopback; + break; + default: + error(1, 0, "Unsupported family %d", family); + } + return addr; +} + +static void attach_ebpf(int fd, uint16_t mod) +{ + static char bpf_log_buf[65536]; + static const char bpf_license[] = "GPL"; + + int bpf_fd; + const struct bpf_insn prog[] = { + /* BPF_MOV64_REG(BPF_REG_6, BPF_REG_1) */ + { BPF_ALU64 | BPF_MOV | BPF_X, BPF_REG_6, BPF_REG_1, 0, 0 }, + /* BPF_LD_ABS(BPF_W, 0) R0 = (uint32_t)skb[0] */ + { BPF_LD | BPF_ABS | BPF_W, 0, 0, 0, 0 }, + /* BPF_ALU64_IMM(BPF_MOD, BPF_REG_0, mod) */ + { BPF_ALU64 | BPF_MOD | BPF_K, BPF_REG_0, 0, 0, mod }, + /* BPF_EXIT_INSN() */ + { BPF_JMP | BPF_EXIT, 0, 0, 0, 0 } + }; + union bpf_attr attr; + + memset(&attr, 0, sizeof(attr)); + attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; + attr.insn_cnt = ARRAY_SIZE(prog); + attr.insns = (uint64_t)prog; + attr.license = (uint64_t)bpf_license; + attr.log_buf = (uint64_t)bpf_log_buf; + attr.log_size = sizeof(bpf_log_buf); + attr.log_level = 1; + attr.kern_version = 0; + + bpf_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr)); + if (bpf_fd < 0) + error(1, errno, "ebpf error. log:\n%s\n", bpf_log_buf); + + if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_EBPF, &bpf_fd, + sizeof(bpf_fd))) + error(1, errno, "failed to set SO_ATTACH_REUSEPORT_EBPF"); +} + +static void attach_cbpf(int fd, uint16_t mod) +{ + struct sock_filter code[] = { + /* A = (uint32_t)skb[0] */ + { BPF_LD | BPF_W | BPF_ABS, 0, 0, 0 }, + /* A = A % mod */ + { BPF_ALU | BPF_MOD, 0, 0, mod }, + /* return A */ + { BPF_RET | BPF_A, 0, 0, 0 }, + }; + struct sock_fprog p = { + .len = ARRAY_SIZE(code), + .filter = code, + }; + + if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_CBPF, &p, sizeof(p))) + error(1, errno, "failed to set SO_ATTACH_REUSEPORT_CBPF"); +} + +static void build_recv_group(const struct test_params p, int fd[], uint16_t mod, + void (*attach_bpf)(int, uint16_t)) +{ + struct sockaddr * const addr = + new_any_sockaddr(p.recv_family, p.recv_port); + int i, opt; + + for (i = 0; i < p.recv_socks; ++i) { + fd[i] = socket(p.recv_family, p.protocol, 0); + if (fd[i] < 0) + error(1, errno, "failed to create recv %d", i); + + opt = 1; + if (setsockopt(fd[i], SOL_SOCKET, SO_REUSEPORT, &opt, + sizeof(opt))) + error(1, errno, "failed to set SO_REUSEPORT on %d", i); + + if (i == 0) + attach_bpf(fd[i], mod); + + if (bind(fd[i], addr, sockaddr_size())) + error(1, errno, "failed to bind recv socket %d", i); + + if (p.protocol == SOCK_STREAM) + if (listen(fd[i], p.recv_socks * 10)) + error(1, errno, "failed to listen on socket"); + } + free(addr); +} + +static void send_from(struct test_params p, uint16_t sport, char *buf, + size_t len) +{ + struct sockaddr * const saddr = new_any_sockaddr(p.send_family, sport); + struct sockaddr * const daddr = + new_loopback_sockaddr(p.send_family, p.recv_port); + const int fd = socket(p.send_family, p.protocol, 0); + + if (fd < 0) + error(1, errno, "failed to create send socket"); + + if (bind(fd, saddr, sockaddr_size())) + error(1, errno, "failed to bind send socket"); + if (connect(fd, daddr, sockaddr_size())) + error(1, errno, "failed to connect"); + + if (send(fd, buf, len, 0) < 0) + error(1, errno, "failed to send message"); + + close(fd); + free(saddr); + free(daddr); +} + +static void test_recv_order(const struct test_params p, int fd[], int mod) +{ + char recv_buf[8], send_buf[8]; + struct msghdr msg; + struct iovec recv_io = { recv_buf, 8 }; + struct epoll_event ev; + int epfd, conn, i, sport, expected; + uint32_t data, ndata; + + epfd = epoll_create(1); + if (epfd < 0) + error(1, errno, "failed to create epoll"); + for (i = 0; i < p.recv_socks; ++i) { + ev.events = EPOLLIN; + ev.data.fd = fd[i]; + if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd[i], &ev)) + error(1, errno, "failed to register sock %d epoll", i); + } + + memset(&msg, 0, sizeof(msg)); + msg.msg_iov = &recv_io; + msg.msg_iovlen = 1; + + for (data = 0; data < p.recv_socks * 2; ++data) { + sport = p.send_port_min + data; + ndata = htonl(data); + memcpy(send_buf, &ndata, sizeof(ndata)); + send_from(p, sport, send_buf, sizeof(ndata)); + + i = epoll_wait(epfd, &ev, 1, -1); + if (i < 0) + error(1, errno, "epoll wait failed"); + + if (p.protocol == SOCK_STREAM) { + conn = accept(ev.data.fd, NULL, NULL); + if (conn < 0) + error(1, errno, "error accepting"); + i = recvmsg(conn, &msg, 0); + close(conn); + } else { + i = recvmsg(ev.data.fd, &msg, 0); + } + if (i < 0) + error(1, errno, "recvmsg error"); + if (i != sizeof(ndata)) + error(1, 0, "expected size %zd got %d", + sizeof(ndata), i); + + for (i = 0; i < p.recv_socks; ++i) + if (ev.data.fd == fd[i]) + break; + memcpy(&ndata, recv_buf, sizeof(ndata)); + fprintf(stderr, "Socket %d: %d\n", i, ntohl(ndata)); + + expected = (sport % mod); + if (i != expected) + error(1, 0, "expected socket %d", expected); + } +} + +static void test_reuseport_ebpf(const struct test_params p) +{ + int i, fd[p.recv_socks]; + + fprintf(stderr, "Testing EBPF mod %zd...\n", p.recv_socks); + build_recv_group(p, fd, p.recv_socks, attach_ebpf); + test_recv_order(p, fd, p.recv_socks); + + fprintf(stderr, "Reprograming, testing mod %zd...\n", p.recv_socks / 2); + attach_ebpf(fd[0], p.recv_socks / 2); + test_recv_order(p, fd, p.recv_socks / 2); + + for (i = 0; i < p.recv_socks; ++i) + close(fd[i]); +} + +static void test_reuseport_cbpf(const struct test_params p) +{ + int i, fd[p.recv_socks]; + + fprintf(stderr, "Testing CBPF mod %zd...\n", p.recv_socks); + build_recv_group(p, fd, p.recv_socks, attach_cbpf); + test_recv_order(p, fd, p.recv_socks); + + fprintf(stderr, "Reprograming, testing mod %zd...\n", p.recv_socks / 2); + attach_cbpf(fd[0], p.recv_socks / 2); + test_recv_order(p, fd, p.recv_socks / 2); + + for (i = 0; i < p.recv_socks; ++i) + close(fd[i]); +} + +static void test_extra_filter(const struct test_params p) +{ + struct sockaddr * const addr = + new_any_sockaddr(p.recv_family, p.recv_port); + int fd1, fd2, opt; + + fprintf(stderr, "Testing too many filters...\n"); + fd1 = socket(p.recv_family, p.protocol, 0); + if (fd1 < 0) + error(1, errno, "failed to create socket 1"); + fd2 = socket(p.recv_family, p.protocol, 0); + if (fd2 < 0) + error(1, errno, "failed to create socket 2"); + + opt = 1; + if (setsockopt(fd1, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt))) + error(1, errno, "failed to set SO_REUSEPORT on socket 1"); + if (setsockopt(fd2, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt))) + error(1, errno, "failed to set SO_REUSEPORT on socket 2"); + + attach_ebpf(fd1, 10); + attach_ebpf(fd2, 10); + + if (bind(fd1, addr, sockaddr_size())) + error(1, errno, "failed to bind recv socket 1"); + + if (!bind(fd2, addr, sockaddr_size()) && errno != EADDRINUSE) + error(1, errno, "bind socket 2 should fail with EADDRINUSE"); + + free(addr); +} + +static void test_filter_no_reuseport(const struct test_params p) +{ + struct sockaddr * const addr = + new_any_sockaddr(p.recv_family, p.recv_port); + const char bpf_license[] = "GPL"; + struct bpf_insn ecode[] = { + { BPF_ALU64 | BPF_MOV | BPF_K, BPF_REG_0, 0, 0, 10 }, + { BPF_JMP | BPF_EXIT, 0, 0, 0, 0 } + }; + struct sock_filter ccode[] = {{ BPF_RET | BPF_A, 0, 0, 0 }}; + union bpf_attr eprog; + struct sock_fprog cprog; + int fd, bpf_fd; + + fprintf(stderr, "Testing filters on non-SO_REUSEPORT socket...\n"); + + memset(&eprog, 0, sizeof(eprog)); + eprog.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; + eprog.insn_cnt = ARRAY_SIZE(ecode); + eprog.insns = (uint64_t)ecode; + eprog.license = (uint64_t)bpf_license; + eprog.kern_version = 0; + + memset(&cprog, 0, sizeof(cprog)); + cprog.len = ARRAY_SIZE(ccode); + cprog.filter = ccode; + + + bpf_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &eprog, sizeof(eprog)); + if (bpf_fd < 0) + error(1, errno, "ebpf error"); + fd = socket(p.recv_family, p.protocol, 0); + if (fd < 0) + error(1, errno, "failed to create socket 1"); + + if (bind(fd, addr, sockaddr_size())) + error(1, errno, "failed to bind recv socket 1"); + + errno = 0; + if (!setsockopt(fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_EBPF, &bpf_fd, + sizeof(bpf_fd)) || errno != EINVAL) + error(1, errno, "setsockopt should have returned EINVAL"); + + errno = 0; + if (!setsockopt(fd, SOL_SOCKET, SO_ATTACH_REUSEPORT_CBPF, &cprog, + sizeof(cprog)) || errno != EINVAL) + error(1, errno, "setsockopt should have returned EINVAL"); + + free(addr); +} + +static void test_filter_without_bind(void) +{ + int fd1, fd2; + + fprintf(stderr, "Testing filter add without bind...\n"); + fd1 = socket(AF_INET, SOCK_DGRAM, 0); + if (fd1 < 0) + error(1, errno, "failed to create socket 1"); + fd2 = socket(AF_INET, SOCK_DGRAM, 0); + if (fd2 < 0) + error(1, errno, "failed to create socket 2"); + + attach_ebpf(fd1, 10); + attach_cbpf(fd2, 10); + + close(fd1); + close(fd2); +} + + +int main(void) +{ + fprintf(stderr, "---- IPv4 UDP ----\n"); + test_reuseport_ebpf((struct test_params) { + .recv_family = AF_INET, + .send_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8000, + .send_port_min = 9000}); + test_reuseport_cbpf((struct test_params) { + .recv_family = AF_INET, + .send_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8001, + .send_port_min = 9020}); + test_extra_filter((struct test_params) { + .recv_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_port = 8002}); + test_filter_no_reuseport((struct test_params) { + .recv_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_port = 8008}); + + fprintf(stderr, "---- IPv6 UDP ----\n"); + test_reuseport_ebpf((struct test_params) { + .recv_family = AF_INET6, + .send_family = AF_INET6, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8003, + .send_port_min = 9040}); + test_reuseport_cbpf((struct test_params) { + .recv_family = AF_INET6, + .send_family = AF_INET6, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8004, + .send_port_min = 9060}); + test_extra_filter((struct test_params) { + .recv_family = AF_INET6, + .protocol = SOCK_DGRAM, + .recv_port = 8005}); + test_filter_no_reuseport((struct test_params) { + .recv_family = AF_INET6, + .protocol = SOCK_DGRAM, + .recv_port = 8009}); + + fprintf(stderr, "---- IPv6 UDP w/ mapped IPv4 ----\n"); + test_reuseport_ebpf((struct test_params) { + .recv_family = AF_INET6, + .send_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8006, + .send_port_min = 9080}); + test_reuseport_cbpf((struct test_params) { + .recv_family = AF_INET6, + .send_family = AF_INET, + .protocol = SOCK_DGRAM, + .recv_socks = 10, + .recv_port = 8007, + .send_port_min = 9100}); + + + test_filter_without_bind(); + + fprintf(stderr, "SUCCESS\n"); + return 0; +} |
