diff options
Diffstat (limited to 'tools/testing/selftests/net/reuseport_dualstack.c')
| -rw-r--r-- | tools/testing/selftests/net/reuseport_dualstack.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/reuseport_dualstack.c b/tools/testing/selftests/net/reuseport_dualstack.c new file mode 100644 index 000000000000..90958aaaafb9 --- /dev/null +++ b/tools/testing/selftests/net/reuseport_dualstack.c @@ -0,0 +1,208 @@ +/* + * It is possible to use SO_REUSEPORT to open multiple sockets bound to + * equivalent local addresses using AF_INET and AF_INET6 at the same time. If + * the AF_INET6 socket has IPV6_V6ONLY set, it's clear which socket should + * receive a given incoming packet. However, when it is not set, incoming v4 + * packets should prefer the AF_INET socket(s). This behavior was defined with + * the original SO_REUSEPORT implementation, but broke with + * e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") + * This test creates these mixed AF_INET/AF_INET6 sockets and asserts the + * AF_INET preference for v4 packets. + */ + +#define _GNU_SOURCE + +#include <arpa/inet.h> +#include <errno.h> +#include <error.h> +#include <linux/in.h> +#include <linux/unistd.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> + +static const int PORT = 8888; + +static void build_rcv_fd(int family, int proto, int *rcv_fds, int count) +{ + struct sockaddr_storage addr; + struct sockaddr_in *addr4; + struct sockaddr_in6 *addr6; + int opt, i; + + 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); + } + + for (i = 0; i < count; ++i) { + rcv_fds[i] = socket(family, proto, 0); + if (rcv_fds[i] < 0) + error(1, errno, "failed to create receive socket"); + + opt = 1; + if (setsockopt(rcv_fds[i], SOL_SOCKET, SO_REUSEPORT, &opt, + sizeof(opt))) + error(1, errno, "failed to set SO_REUSEPORT"); + + if (bind(rcv_fds[i], (struct sockaddr *)&addr, sizeof(addr))) + error(1, errno, "failed to bind receive socket"); + + if (proto == SOCK_STREAM && listen(rcv_fds[i], 10)) + error(1, errno, "failed to listen on receive port"); + } +} + +static void send_from_v4(int proto) +{ + struct sockaddr_in saddr, daddr; + int fd; + + saddr.sin_family = AF_INET; + saddr.sin_addr.s_addr = htonl(INADDR_ANY); + saddr.sin_port = 0; + + daddr.sin_family = AF_INET; + daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK); + daddr.sin_port = htons(PORT); + + fd = socket(AF_INET, proto, 0); + if (fd < 0) + error(1, errno, "failed to create send socket"); + + if (bind(fd, (struct sockaddr *)&saddr, sizeof(saddr))) + error(1, errno, "failed to bind send socket"); + + if (connect(fd, (struct sockaddr *)&daddr, sizeof(daddr))) + error(1, errno, "failed to connect send socket"); + + if (send(fd, "a", 1, 0) < 0) + error(1, errno, "failed to send message"); + + close(fd); +} + +static int receive_once(int epfd, int proto) +{ + struct epoll_event ev; + int i, fd; + char buf[8]; + + i = epoll_wait(epfd, &ev, 1, -1); + if (i < 0) + error(1, errno, "epoll_wait failed"); + + if (proto == SOCK_STREAM) { + fd = accept(ev.data.fd, NULL, NULL); + if (fd < 0) + error(1, errno, "failed to accept"); + i = recv(fd, buf, sizeof(buf), 0); + close(fd); + } else { + i = recv(ev.data.fd, buf, sizeof(buf), 0); + } + + if (i < 0) + error(1, errno, "failed to recv"); + + return ev.data.fd; +} + +static void test(int *rcv_fds, int count, int proto) +{ + struct epoll_event ev; + int epfd, i, test_fd; + uint16_t test_family; + socklen_t len; + + epfd = epoll_create(1); + if (epfd < 0) + error(1, errno, "failed to create epoll"); + + ev.events = EPOLLIN; + for (i = 0; i < count; ++i) { + ev.data.fd = rcv_fds[i]; + if (epoll_ctl(epfd, EPOLL_CTL_ADD, rcv_fds[i], &ev)) + error(1, errno, "failed to register sock epoll"); + } + + send_from_v4(proto); + + test_fd = receive_once(epfd, proto); + if (getsockopt(test_fd, SOL_SOCKET, SO_DOMAIN, &test_family, &len)) + error(1, errno, "failed to read socket domain"); + if (test_family != AF_INET) + error(1, 0, "expected to receive on v4 socket but got v6 (%d)", + test_family); + + close(epfd); +} + +int main(void) +{ + int rcv_fds[32], i; + + fprintf(stderr, "---- UDP IPv4 created before IPv6 ----\n"); + build_rcv_fd(AF_INET, SOCK_DGRAM, rcv_fds, 5); + build_rcv_fd(AF_INET6, SOCK_DGRAM, &(rcv_fds[5]), 5); + test(rcv_fds, 10, SOCK_DGRAM); + for (i = 0; i < 10; ++i) + close(rcv_fds[i]); + + fprintf(stderr, "---- UDP IPv6 created before IPv4 ----\n"); + build_rcv_fd(AF_INET6, SOCK_DGRAM, rcv_fds, 5); + build_rcv_fd(AF_INET, SOCK_DGRAM, &(rcv_fds[5]), 5); + test(rcv_fds, 10, SOCK_DGRAM); + for (i = 0; i < 10; ++i) + close(rcv_fds[i]); + + /* NOTE: UDP socket lookups traverse a different code path when there + * are > 10 sockets in a group. + */ + fprintf(stderr, "---- UDP IPv4 created before IPv6 (large) ----\n"); + build_rcv_fd(AF_INET, SOCK_DGRAM, rcv_fds, 16); + build_rcv_fd(AF_INET6, SOCK_DGRAM, &(rcv_fds[16]), 16); + test(rcv_fds, 32, SOCK_DGRAM); + for (i = 0; i < 32; ++i) + close(rcv_fds[i]); + + fprintf(stderr, "---- UDP IPv6 created before IPv4 (large) ----\n"); + build_rcv_fd(AF_INET6, SOCK_DGRAM, rcv_fds, 16); + build_rcv_fd(AF_INET, SOCK_DGRAM, &(rcv_fds[16]), 16); + test(rcv_fds, 32, SOCK_DGRAM); + for (i = 0; i < 32; ++i) + close(rcv_fds[i]); + + fprintf(stderr, "---- TCP IPv4 created before IPv6 ----\n"); + build_rcv_fd(AF_INET, SOCK_STREAM, rcv_fds, 5); + build_rcv_fd(AF_INET6, SOCK_STREAM, &(rcv_fds[5]), 5); + test(rcv_fds, 10, SOCK_STREAM); + for (i = 0; i < 10; ++i) + close(rcv_fds[i]); + + fprintf(stderr, "---- TCP IPv6 created before IPv4 ----\n"); + build_rcv_fd(AF_INET6, SOCK_STREAM, rcv_fds, 5); + build_rcv_fd(AF_INET, SOCK_STREAM, &(rcv_fds[5]), 5); + test(rcv_fds, 10, SOCK_STREAM); + for (i = 0; i < 10; ++i) + close(rcv_fds[i]); + + fprintf(stderr, "SUCCESS\n"); + return 0; +} |
