From 9c0ed46f68cada9f3455be91adb553d020012596 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Sat, 9 Mar 2019 11:56:05 +0100 Subject: Rename 'qa' directory to 'tests' When searching for library tests, 'qa' is easily overlooked. Use a more common name instead. Suggested-by: Pablo Neira Ayuso Signed-off-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso --- tests/nssocket.c | 739 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 739 insertions(+) create mode 100644 tests/nssocket.c (limited to 'tests/nssocket.c') diff --git a/tests/nssocket.c b/tests/nssocket.c new file mode 100644 index 0000000..114938c --- /dev/null +++ b/tests/nssocket.c @@ -0,0 +1,739 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include "config.h" +#include "nssocket.h" + +int fdpair[2]; +#define PARENT_FD (fdpair[0]) +#define CHILD_FD (fdpair[1]) + +pid_t child_pid; + +void add_child(pid_t pid) +{ + /* XXX: check excess MAX_CHILD */ + children[nchild++] = pid; +} + +static int get_unaligned_int(const void *s) +{ + int x; + memcpy(&x, s, sizeof(x)); + return x; +} + +static void put_unaligned_int(void *d, int x) +{ + memcpy(d, &x, sizeof(x)); +} + +/* + * message exchange via socketpair using send/recv msg() + * + * - use cdata: + * cdata represents a file descriptor + * cmd[0] means -errno + * + * - without cdata: + * cmd[0] means: + * > 0: command + * == 0: sync, echo + * < 0: -errno + * + * it's an given fact that tx() and rx() never fail. + */ +ssize_t tx(int fd, int *cmd, uint8_t cmdlen, int cdata) +{ + struct msghdr msg; + struct iovec iov[cmdlen]; + size_t cmsglen = CMSG_SPACE(sizeof(int)); + char control[CMSG_SPACE(sizeof(int))]; + struct cmsghdr *cmsg; + int i; + + memset(&msg, 0, sizeof(struct msghdr)); + memset(iov, 0, sizeof(struct iovec) * cmdlen); + + msg.msg_iov = iov; + msg.msg_iovlen = cmdlen; + for (i = 0; i < cmdlen; i++) { + iov[i].iov_len = sizeof(int); + iov[i].iov_base = &cmd[i]; + } + if (cdata) { + msg.msg_control = control; + msg.msg_controllen = cmsglen; + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + put_unaligned_int(CMSG_DATA(cmsg), cdata); + } + + return sendmsg(fd, &msg, 0); +} + +ssize_t rx(int fd, int *cmd, uint8_t cmdlen, int *cdata) +{ + struct msghdr msg; + struct iovec iov[cmdlen]; + size_t cmsglen = CMSG_SPACE(sizeof(int)); + char control[CMSG_SPACE(sizeof(int))]; + struct cmsghdr *cmsg; + ssize_t ret; + int i; + + memset(&msg, 0, sizeof(struct msghdr)); + memset(iov, 0, sizeof(struct iovec)); + + msg.msg_iov = iov; + msg.msg_iovlen = cmdlen; + for (i = 0; i < cmdlen; i++) { + iov[i].iov_len = sizeof(int); + iov[i].iov_base = &cmd[i]; + } + if (cdata != NULL) { + msg.msg_control = control; + msg.msg_controllen = cmsglen; + } + + ret = recvmsg(fd, &msg, 0); + if (ret == -1) { + perror("recvmsg"); + return ret; + } + + if (cdata == NULL) + return ret; + + cmsg = CMSG_FIRSTHDR(&msg); + if (cmsg == NULL || cmsg->cmsg_len != CMSG_LEN(sizeof(int)) + || cmsg->cmsg_level != SOL_SOCKET + || cmsg->cmsg_type != SCM_RIGHTS) { + errno = EBADMSG; + return -1; + } + *cdata = get_unaligned_int(CMSG_DATA(cmsg)); + + return ret; +} + +int tx_cmd(int fd, int cmd) +{ + return tx(fd, &cmd, 1, 0); +} + +int rx_cmd(int fd) +{ + int cmd; + if (rx((fd), &cmd, 1, NULL) == -1) + return -1; + return cmd; +} + +int tx_fd(int fd1, int fd2, int e) +{ + return tx(fd1, &e, 1, fd2); +} + +int rx_fd(int fd1) +{ + int e, fd2; + + if (rx(fd1, &e, 1, &fd2) == -1) + return -1; + + errno = -e; + return fd2; +} + +/* + * copy from ip/ipnetns.c::iproute2 + */ +#ifndef HAVE_SETNS +#include +static int setns(int fd, int nstype) +{ +#ifdef __NR_setns + return syscall(__NR_setns, fd, nstype); +#else + errno = ENOSYS; + return -1; +#endif +} +#endif /* HAVE_SETNS */ + +#define NETNS_RUN_DIR "/var/run/netns" +static int netns_setup(const char *name) +{ + /* Setup the proper environment for apps that are not netns + * aware, and execute a program in that environment. + */ + char net_path[MAXPATHLEN]; + int netns; + + snprintf(net_path, sizeof(net_path), "%s/%s", NETNS_RUN_DIR, name); + netns = open(net_path, O_RDONLY | O_CLOEXEC); + if (netns < 0) { + fprintf(stderr, "Cannot open network namespace \"%s\": %s\n", + name, strerror(errno)); + return -1; + } + + if (setns(netns, CLONE_NEWNET) < 0) { + fprintf(stderr, "setting the network namespace \"%s\" failed: %s\n", + name, strerror(errno)); + return -1; + } + + if (unshare(CLONE_NEWNS) < 0) { + fprintf(stderr, "unshare failed: %s\n", strerror(errno)); + return -1; + } + /* Don't let any mounts propagate back to the parent */ + if (mount("", "/", "none", MS_SLAVE | MS_REC, NULL)) { + fprintf(stderr, "\"mount --make-rslave /\" failed: %s\n", + strerror(errno)); + return -1; + } + /* Mount a version of /sys that describes the network namespace */ + if (umount2("/sys", MNT_DETACH) < 0) { + fprintf(stderr, "umount of /sys failed: %s\n", strerror(errno)); + return -1; + } + if (mount(name, "/sys", "sysfs", 0, NULL) < 0) { + fprintf(stderr, "mount of /sys failed: %s\n",strerror(errno)); + return -1; + } + + return 0; +} + +static void child(const char *nsname) +{ + int cmd = CMD_SYNC; + int params[3]; /* XXX: magic number, see enum CALL_ */ + int sockfd; + + if (netns_setup(nsname) == -1) + child_exit("netns_setup", EXIT_FAILURE); + + /* sync with parent */ + if (tx_cmd(CHILD_FD, CMD_SYNC) == -1) + child_exit("tx_cmd", EXIT_FAILURE); + + /* waiting cmd */ + while (1) { + debug_ns("child waiting for cmd...\n"); + cmd = rx_cmd(CHILD_FD); + switch (cmd) { + case CMD_DONE: + debug_ns("child received CMD_DONE - exiting\n"); + close(CHILD_FD); + child_exit("receive CMD_DONE", EXIT_SUCCESS); + break; + case CMD_SOCKET: + if (rx(CHILD_FD, params, 3, NULL) == -1) + child_exit("rx", EXIT_FAILURE); + debug_ns("child received CMD_SOCKET -" + " domain: %d, type: %d, protocol: %d\n", + params[0], params[1], params[2]); + sockfd = socket(params[0], params[1], params[2]); + if (tx_fd(CHILD_FD, sockfd, -errno) == -1) + child_exit("tx_fd", EXIT_FAILURE); + break; + default: + debug_ns("child received unknown cmd: %d\n", cmd); + child_exit("receive unknown cmd", EXIT_FAILURE); + break; + } + } +} + +/* + * kill all the other registered child by SIGKILL + * + * SIGCHLD will not be raised if child has killed in SIGABRT handler + */ +static void sigchld_handler(int signum) +{ + pid_t pid; + int status, i, fail = 0; + + while ((pid = waitpid(-1, &status, WNOHANG)) > 0) { + debug_ns("receive SIGCHLD - pid: %d\n", pid); + if (WIFEXITED(status)) + fail |= WEXITSTATUS(status); + else if (WIFSIGNALED(status) || WCOREDUMP(status)) + fail |= status; + if (pid == child_pid) + child_pid = 0; + for (i = 0; i < nchild; i++) + if (children[i] == pid) + children[i] = 0; + else + kill(children[i], SIGKILL); + } + if (pid == -1 && errno != ECHILD) + fail |= errno; + + /* overdoing? kill myself + * if (fail) kill(0, SIGKILL); + */ +} + +/* + * core public API + */ +int init_nssocket(const char *nsname) +{ + pid_t pid; + struct sigaction sa; + + if (socketpair(AF_UNIX, SOCK_STREAM, 0, fdpair) == -1) + return -1; + + sigemptyset(&sa.sa_mask); + sa.sa_handler = sigchld_handler; + sa.sa_flags = SA_NOCLDSTOP; + if (sigaction(SIGCHLD, &sa, NULL) == -1) + return -1; + + fflush(stdout); + pid = fork(); + switch (pid) { + case -1: + return -1; + break; + case 0: + child(nsname); /* not return */ + break; + default: + child_pid = pid; + add_child(pid); + if (rx_cmd(PARENT_FD) < 0) { + parent_fail("rx_cmd"); + return -1; + } + break; + } + + return 0; +} + +int fini_nssocket(void) +{ + int status; + sigset_t block_mask; + pid_t pid; + + sigemptyset(&block_mask); + sigaddset(&block_mask, SIGCHLD); + if (sigprocmask(SIG_SETMASK, &block_mask, NULL) == -1) + return -1; + tx_cmd(PARENT_FD, CMD_DONE); + close(PARENT_FD); + pid = waitpid(child_pid, &status, 0); + child_pid = 0; + if (pid < 0) + return -1; + if (WIFEXITED(status) && WEXITSTATUS(status) == 0) + return 0; + + return status; +} + +int nssocket(int domain, int type, int protocol) +{ + int cmd[] = {CMD_SOCKET, domain, type, protocol}; + + if (child_pid == 0 || kill(child_pid, 0) == -1) { + errno = ECHILD; + return -1; + } + tx(PARENT_FD, cmd, 4, 0); + return rx_fd(PARENT_FD); +} + +/* + * utils API + */ +int debug_nfct_cb(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct; + uint32_t type = NFCT_T_UNKNOWN; + char buf[4096]; + + switch(nlh->nlmsg_type & 0xFF) { + case IPCTNL_MSG_CT_NEW: + if (nlh->nlmsg_flags & (NLM_F_CREATE|NLM_F_EXCL)) + type = NFCT_T_NEW; + else + type = NFCT_T_UPDATE; + break; + case IPCTNL_MSG_CT_DELETE: + type = NFCT_T_DESTROY; + break; + } + + ct = nfct_new(); + if (ct == NULL) + return MNL_CB_OK; + + nfct_nlmsg_parse(nlh, ct); + nfct_snprintf(buf, sizeof(buf), ct, type, NFCT_O_DEFAULT, 0); + debug("%s\n", buf); + nfct_destroy(ct); + + return MNL_CB_OK; +} + +struct mnl_socket *mnl_nssocket_open(int bus) +{ + int fd; + struct mnl_socket *nl; + + fd = nssocket(AF_NETLINK, SOCK_RAW, bus); + if (fd == -1) + return NULL; + + nl = mnl_socket_fdopen(fd); + if (nl == NULL) { + close(fd); + return NULL; + } + return nl; +} + +/* + * assert utilities + */ +struct nf_conntrack *author_new(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct; + + assert((nlh->nlmsg_type & 0xFF) == IPCTNL_MSG_CT_NEW); + assert(nlh->nlmsg_flags == (NLM_F_CREATE | NLM_F_EXCL)); + ct = nfct_new(); + assert(ct != NULL); + assert(nfct_nlmsg_parse((nlh), ct) == 0); + assert_proto(ct, AF_INET, *(uint8_t *) data); + assert_inaddr(ct, VETH_PARENT_ADDR, VETH_CHILD_ADDR); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_SEEN_REPLY) == 0); + timeout.tv_sec = nfct_get_attr_u32(ct, ATTR_TIMEOUT) + 1; + + return ct; +} + +struct nf_conntrack *author_update(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct; + + assert((nlh->nlmsg_type & 0xFF) == IPCTNL_MSG_CT_NEW); + assert(nlh->nlmsg_flags == 0); + ct = nfct_new(); + assert(ct != NULL); + assert(nfct_nlmsg_parse((nlh), ct) == 0); + assert_proto(ct, AF_INET, *(uint8_t *) data); + assert_inaddr(ct, VETH_PARENT_ADDR, VETH_CHILD_ADDR); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_SEEN_REPLY)); + timeout.tv_sec = nfct_get_attr_u32(ct, ATTR_TIMEOUT) + 1; + + return ct; +} + +struct nf_conntrack *author_destroy(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct; + + assert((nlh->nlmsg_type & 0xFF) == IPCTNL_MSG_CT_DELETE); + assert(nlh->nlmsg_flags == 0); + ct = nfct_new(); + assert(ct != NULL); + assert(nfct_nlmsg_parse((nlh), ct) == 0); + assert_proto(ct, AF_INET, *(uint8_t *) data); + assert_inaddr(ct, VETH_PARENT_ADDR, VETH_CHILD_ADDR); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_SEEN_REPLY)); + + return ct; +} + +void assert_proto(const struct nf_conntrack *ct, + uint8_t l3proto, uint8_t l4proto) +{ + assert(nfct_get_attr_u8(ct, ATTR_ORIG_L3PROTO) == l3proto); + assert(nfct_get_attr_u8(ct, ATTR_REPL_L3PROTO) == l3proto); + assert(nfct_get_attr_u8(ct, ATTR_ORIG_L4PROTO) == l4proto); + assert(nfct_get_attr_u8(ct, ATTR_REPL_L4PROTO) == l4proto); +} + +void assert_inaddr(const struct nf_conntrack *ct, + const char *src, const char *dst) +{ + struct in_addr addr; + assert(inet_aton((src), &addr) != 0); + assert(nfct_get_attr_u32((ct), ATTR_ORIG_IPV4_SRC) == addr.s_addr); + assert(nfct_get_attr_u32((ct), ATTR_REPL_IPV4_DST) == addr.s_addr); + assert(inet_aton((dst), &addr) != 0); + assert(nfct_get_attr_u32((ct), ATTR_ORIG_IPV4_DST) == addr.s_addr); + assert(nfct_get_attr_u32((ct), ATTR_REPL_IPV4_SRC) == addr.s_addr); +} + +void assert_port(const struct nf_conntrack *ct, + uint16_t src, uint16_t dst) +{ + if ((src)) { + assert(nfct_get_attr_u16((ct), ATTR_ORIG_PORT_SRC) == htons((src))); + assert(nfct_get_attr_u16((ct), ATTR_REPL_PORT_DST) == htons((src))); + } + if ((dst)) { + assert(nfct_get_attr_u16((ct), ATTR_ORIG_PORT_DST) == htons((dst))); + assert(nfct_get_attr_u16((ct), ATTR_REPL_PORT_SRC) == htons((dst))); + } +} + +void assert_typecode(const struct nf_conntrack *ct, + uint8_t type, uint8_t code) +{ + assert(nfct_get_attr_u8((ct), ATTR_ICMP_TYPE) == type); + assert(nfct_get_attr_u8((ct), ATTR_ICMP_CODE) == code); +} + +int cb_icmp_new(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_new(nlh, data); + assert_typecode(ct, ICMP_TYPE, ICMP_CODE); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_icmp_update(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_typecode(ct, ICMP_TYPE, ICMP_CODE); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_icmp_destroy(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_destroy(nlh, data); + assert_typecode(ct, ICMP_TYPE, ICMP_CODE); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_udp_new(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_new(nlh, data); + assert_port(ct, 0, DSTPORT); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_udp_update(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_udp_destroy(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_destroy(nlh, data); + assert_port(ct, 0, DSTPORT); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_new(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_new(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_SYN_SENT); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_syn_recv(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_SYN_RECV); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_established(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_ESTABLISHED); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_ASSURED)); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_fin_wait(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_FIN_WAIT); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_ASSURED)); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_close_wait(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_CLOSE_WAIT); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_ASSURED)); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_close(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_update(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_get_attr_u8(ct, ATTR_TCP_STATE) == TCP_CONNTRACK_CLOSE); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_ASSURED)); + nfct_destroy(ct); + return MNL_CB_OK; +} + +int cb_tcp_destroy(const struct nlmsghdr *nlh, void *data) +{ + struct nf_conntrack *ct = author_destroy(nlh, data); + assert_port(ct, 0, DSTPORT); + assert(nfct_attr_is_set(ct, ATTR_TCP_STATE) == 0); + assert((nfct_get_attr_u32(ct, ATTR_STATUS) & IPS_ASSURED)); + nfct_destroy(ct); + return MNL_CB_OK; +} + +void tcp_echo(const struct mnl_socket *nl, + const char *pre, const char *post) +{ + uint8_t proto = IPPROTO_TCP; + + sync_fifo(pre); + timeout.tv_sec = INIT_TIMEOUT; + handle_qacb(nl, true, cb_tcp_new, &proto); + handle_qacb(nl, true, cb_tcp_syn_recv, &proto); + handle_qacb(nl, true, cb_tcp_established, &proto); + handle_qacb(nl, true, cb_tcp_fin_wait, &proto); + handle_qacb(nl, true, cb_tcp_close_wait, &proto); + handle_qacb(nl, true, cb_tcp_close, &proto); + handle_qacb(nl, true, cb_tcp_destroy, &proto); + handle_qacb(nl, false, NULL, NULL); + sync_fifo(post); +} + +int handle_qacb(const struct mnl_socket *nl, bool should_receive, + int(*cb)(const struct nlmsghdr *nlh, void *data), void *data) +{ + char buf[MNL_SOCKET_BUFFER_SIZE]; + fd_set rfds; + int ret, fd = mnl_socket_get_fd(nl); + bool receive_nfnl; + + FD_ZERO(&rfds); + FD_SET(fd, &rfds); + if (select(fd + 1, &rfds, NULL, NULL, &timeout) < 0) + child_exit("select", EXIT_FAILURE); + receive_nfnl = FD_ISSET(fd, &rfds); + if (should_receive) { + assert(receive_nfnl == true); + } else { + assert(receive_nfnl == false); + return MNL_CB_ERROR; + } + + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + if (ret == -1) + child_exit("mnl_socket_recvfrom", EXIT_FAILURE); + mnl_cb_run(buf, ret, 0, 0, debug_nfct_cb, NULL); + if (cb != NULL) { + ret = mnl_cb_run(buf, ret, 0, 0, cb, data); + if (ret == -1) + child_exit("mnl_cb_run", EXIT_FAILURE); + return ret; + } + + return MNL_CB_OK; +} + +static void sigabrt_handler(int signum) +{ + fini_nssocket(); +} + +struct mnl_socket *mnl_event_nssocket(const char *nsname) +{ + struct mnl_socket *nl; + struct sigaction sa; + + sigemptyset(&sa.sa_mask); + sa.sa_flags = 0; + sa.sa_handler = sigabrt_handler; + if (sigaction(SIGABRT, &sa, NULL) == -1) + return NULL; + + if (init_nssocket(nsname) == -1) + return NULL; + + nl = mnl_nssocket_open(NETLINK_NETFILTER); + if (nl == NULL) + return NULL; + if (mnl_socket_bind(nl, NF_NETLINK_CONNTRACK_NEW | + NF_NETLINK_CONNTRACK_UPDATE | + NF_NETLINK_CONNTRACK_DESTROY, + MNL_SOCKET_AUTOPID) < 0) { + parent_fail("mnl_socket_bind"); + mnl_socket_close(nl); + return NULL; + } + + return nl; +} + +void sync_fifo(const char *name) +{ + struct stat statbuf; + int fd = open(name, O_WRONLY); + if (fd == -1) { + parent_fail("open fifo"); + exit(EXIT_FAILURE); + } + if (fstat(fd, &statbuf) == -1) { + parent_fail("fstat fifo"); + exit(EXIT_FAILURE); + } + if (!S_ISFIFO(statbuf.st_mode)) { + parent_fail("S_ISFIFO"); + exit(EXIT_FAILURE); + } + close(fd); +} -- cgit v1.2.3