ctdb-tests: Avoid ShellCheck warnings

[Samba.git] / ctdb / tcp / tcp_connect.c

/* 
   ctdb over TCP

   Copyright (C) Andrew Tridgell  2006
   Copyright (C) Ronnie Sahlberg  2008

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, see <http://www.gnu.org/licenses/>.
*/

#include "replace.h"
#include "system/network.h"
#include "system/filesys.h"

#include <talloc.h>
#include <tevent.h>

#include "lib/util/debug.h"
#include "lib/util/time.h"
#include "lib/util/blocking.h"

#include "ctdb_private.h"

#include "common/system.h"
#include "common/common.h"
#include "common/logging.h"

#include "ctdb_tcp.h"

/*
  stop any outgoing connection (established or pending) to a node
 */
void ctdb_tcp_stop_outgoing(struct ctdb_node *node)
{
        struct ctdb_tcp_node *tnode = talloc_get_type(
                node->transport_data, struct ctdb_tcp_node);

        TALLOC_FREE(tnode->out_queue);
        TALLOC_FREE(tnode->connect_te);
        TALLOC_FREE(tnode->connect_fde);
        if (tnode->out_fd != -1) {
                close(tnode->out_fd);
                tnode->out_fd = -1;
        }
}

/*
  stop incoming connection to a node
 */
void ctdb_tcp_stop_incoming(struct ctdb_node *node)
{
        struct ctdb_tcp_node *tnode = talloc_get_type(
                node->transport_data, struct ctdb_tcp_node);

        TALLOC_FREE(tnode->in_queue);
}

/*
  called when a complete packet has come in - should not happen on this socket
  unless the other side closes the connection with RST or FIN
 */
void ctdb_tcp_tnode_cb(uint8_t *data, size_t cnt, void *private_data)
{
        struct ctdb_node *node = talloc_get_type(private_data, struct ctdb_node);

        node->ctdb->upcalls->node_dead(node);

        TALLOC_FREE(data);
}

/*
  called when socket becomes writeable on connect
*/
static void ctdb_node_connect_write(struct tevent_context *ev,
                                    struct tevent_fd *fde,
                                    uint16_t flags, void *private_data)
{
        struct ctdb_node *node = talloc_get_type(private_data,
                                                 struct ctdb_node);
        struct ctdb_tcp_node *tnode = talloc_get_type(node->transport_data,
                                                      struct ctdb_tcp_node);
        struct ctdb_context *ctdb = node->ctdb;
        int error = 0;
        socklen_t len = sizeof(error);
        int one = 1;
        int ret;

        TALLOC_FREE(tnode->connect_te);

        ret = getsockopt(tnode->out_fd, SOL_SOCKET, SO_ERROR, &error, &len);
        if (ret != 0 || error != 0) {
                ctdb_tcp_stop_outgoing(node);
                tnode->connect_te = tevent_add_timer(ctdb->ev, tnode,
                                                    timeval_current_ofs(1, 0),
                                                    ctdb_tcp_node_connect, node);
                return;
        }

        TALLOC_FREE(tnode->connect_fde);

        ret = setsockopt(tnode->out_fd,
                         IPPROTO_TCP,
                         TCP_NODELAY,
                         (char *)&one,
                         sizeof(one));
        if (ret == -1) {
                DBG_WARNING("Failed to set TCP_NODELAY on fd - %s\n",
                          strerror(errno));
        }
        ret = setsockopt(tnode->out_fd,
                         SOL_SOCKET,
                         SO_KEEPALIVE,(char *)&one,
                         sizeof(one));
        if (ret == -1) {
                DBG_WARNING("Failed to set KEEPALIVE on fd - %s\n",
                            strerror(errno));
        }

        tnode->out_queue = ctdb_queue_setup(node->ctdb,
                                            tnode,
                                            tnode->out_fd,
                                            CTDB_TCP_ALIGNMENT,
                                            ctdb_tcp_tnode_cb,
                                            node,
                                            "to-node-%s",
                                            node->name);
        if (tnode->out_queue == NULL) {
                DBG_ERR("Failed to set up outgoing queue\n");
                ctdb_tcp_stop_outgoing(node);
                tnode->connect_te = tevent_add_timer(ctdb->ev,
                                                     tnode,
                                                     timeval_current_ofs(1, 0),
                                                     ctdb_tcp_node_connect,
                                                     node);
                return;
        }

        /* the queue subsystem now owns this fd */
        tnode->out_fd = -1;

        /*
         * Mark the node to which this connection has been established
         * as connected, but only if the corresponding listening
         * socket is also connected
         */
        if (tnode->in_queue != NULL) {
                node->ctdb->upcalls->node_connected(node);
        }
}


static void ctdb_tcp_node_connect_timeout(struct tevent_context *ev,
                                          struct tevent_timer *te,
                                          struct timeval t,
                                          void *private_data);

/*
  called when we should try and establish a tcp connection to a node
*/
static void ctdb_tcp_start_outgoing(struct ctdb_node *node)
{
        struct ctdb_tcp_node *tnode = talloc_get_type(node->transport_data,
                                                      struct ctdb_tcp_node);
        struct ctdb_context *ctdb = node->ctdb;
        ctdb_sock_addr sock_in;
        int sockin_size;
        int sockout_size;
        ctdb_sock_addr sock_out;
        int ret;

        sock_out = node->address;

        tnode->out_fd = socket(sock_out.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
        if (tnode->out_fd == -1) {
                DBG_ERR("Failed to create socket\n");
                goto failed;
        }

        ret = set_blocking(tnode->out_fd, false);
        if (ret != 0) {
                DBG_ERR("Failed to set socket non-blocking (%s)\n",
                        strerror(errno));
                goto failed;
        }

        set_close_on_exec(tnode->out_fd);

        DBG_DEBUG("Created TCP SOCKET FD:%d\n", tnode->out_fd);

        /* Bind our side of the socketpair to the same address we use to listen
         * on incoming CTDB traffic.
         * We must specify this address to make sure that the address we expose to
         * the remote side is actually routable in case CTDB traffic will run on
         * a dedicated non-routeable network.
         */
        sock_in = *ctdb->address;

        /* AIX libs check to see if the socket address and length
           arguments are consistent with each other on calls like
           connect().   Can not get by with just sizeof(sock_in),
           need sizeof(sock_in.ip).
        */
        switch (sock_in.sa.sa_family) {
        case AF_INET:
                sock_in.ip.sin_port = 0 /* Any port */;
                sockin_size = sizeof(sock_in.ip);
                sockout_size = sizeof(sock_out.ip);
                break;
        case AF_INET6:
                sock_in.ip6.sin6_port = 0 /* Any port */;
                sockin_size = sizeof(sock_in.ip6);
                sockout_size = sizeof(sock_out.ip6);
                break;
        default:
                DBG_ERR("Unknown address family %u\n", sock_in.sa.sa_family);
                /* Can't happen to due to address parsing restrictions */
                goto failed;
        }

        ret = bind(tnode->out_fd, (struct sockaddr *)&sock_in, sockin_size);
        if (ret == -1) {
                DBG_ERR("Failed to bind socket (%s)\n", strerror(errno));
                goto failed;
        }

        ret = connect(tnode->out_fd,
                      (struct sockaddr *)&sock_out,
                      sockout_size);
        if (ret != 0 && errno != EINPROGRESS) {
                goto failed;
        }

        /* non-blocking connect - wait for write event */
        tnode->connect_fde = tevent_add_fd(node->ctdb->ev,
                                           tnode,
                                           tnode->out_fd,
                                           TEVENT_FD_WRITE|TEVENT_FD_READ,
                                           ctdb_node_connect_write,
                                           node);

        /* don't give it long to connect - retry in one second. This ensures
           that we find a node is up quickly (tcp normally backs off a syn reply
           delay by quite a lot) */
        tnode->connect_te = tevent_add_timer(ctdb->ev,
                                             tnode,
                                             timeval_current_ofs(1, 0),
                                             ctdb_tcp_node_connect_timeout,
                                             node);

        return;

failed:
        ctdb_tcp_stop_outgoing(node);
        tnode->connect_te = tevent_add_timer(ctdb->ev,
                                             tnode,
                                             timeval_current_ofs(1, 0),
                                             ctdb_tcp_node_connect,
                                             node);
}

void ctdb_tcp_node_connect(struct tevent_context *ev,
                           struct tevent_timer *te,
                           struct timeval t,
                           void *private_data)
{
        struct ctdb_node *node = talloc_get_type_abort(private_data,
                                                       struct ctdb_node);

        ctdb_tcp_start_outgoing(node);
}

static void ctdb_tcp_node_connect_timeout(struct tevent_context *ev,
                                          struct tevent_timer *te,
                                          struct timeval t,
                                          void *private_data)
{
        struct ctdb_node *node = talloc_get_type_abort(private_data,
                                                       struct ctdb_node);

        ctdb_tcp_stop_outgoing(node);
        ctdb_tcp_start_outgoing(node);
}

/*
  called when we get contacted by another node
  currently makes no attempt to check if the connection is really from a ctdb
  node in our cluster
*/
static void ctdb_listen_event(struct tevent_context *ev, struct tevent_fd *fde,
                              uint16_t flags, void *private_data)
{
        struct ctdb_context *ctdb = talloc_get_type(private_data, struct ctdb_context);
        struct ctdb_tcp *ctcp = talloc_get_type(ctdb->transport_data,
                                                struct ctdb_tcp);
        ctdb_sock_addr addr;
        socklen_t len;
        int fd;
        struct ctdb_node *node;
        struct ctdb_tcp_node *tnode;
        int one = 1;
        int ret;

        memset(&addr, 0, sizeof(addr));
        len = sizeof(addr);
        fd = accept(ctcp->listen_fd, (struct sockaddr *)&addr, &len);
        if (fd == -1) return;
        smb_set_close_on_exec(fd);

        node = ctdb_ip_to_node(ctdb, &addr);
        if (node == NULL) {
                D_ERR("Refused connection from unknown node %s\n",
                      ctdb_addr_to_str(&addr));
                close(fd);
                return;
        }

        tnode = talloc_get_type_abort(node->transport_data,
                                      struct ctdb_tcp_node);
        if (tnode == NULL) {
                /* This can't happen - see ctdb_tcp_initialise() */
                DBG_ERR("INTERNAL ERROR setting up connection from node %s\n",
                        ctdb_addr_to_str(&addr));
                close(fd);
                return;
        }

        if (tnode->in_queue != NULL) {
                DBG_ERR("Incoming queue active, rejecting connection from %s\n",
                        ctdb_addr_to_str(&addr));
                close(fd);
                return;
        }

        ret = set_blocking(fd, false);
        if (ret != 0) {
                DBG_ERR("Failed to set socket non-blocking (%s)\n",
                        strerror(errno));
                close(fd);
                return;
        }

        set_close_on_exec(fd);

        DBG_DEBUG("Created SOCKET FD:%d to incoming ctdb connection\n", fd);

        ret = setsockopt(fd,
                         SOL_SOCKET,
                         SO_KEEPALIVE,
                         (char *)&one,
                         sizeof(one));
        if (ret == -1) {
                DBG_WARNING("Failed to set KEEPALIVE on fd - %s\n",
                            strerror(errno));
        }

        tnode->in_queue = ctdb_queue_setup(ctdb,
                                           tnode,
                                           fd,
                                           CTDB_TCP_ALIGNMENT,
                                           ctdb_tcp_read_cb,
                                           node,
                                           "ctdbd-%s",
                                           ctdb_addr_to_str(&addr));
        if (tnode->in_queue == NULL) {
                DBG_ERR("Failed to set up incoming queue\n");
                close(fd);
                return;
        }

       /*
        * Mark the connecting node as connected, but only if the
        * corresponding outbound connected is also up
        */
        if (tnode->out_queue != NULL) {
                node->ctdb->upcalls->node_connected(node);
        }
 }


/*
  automatically find which address to listen on
*/
static int ctdb_tcp_listen_automatic(struct ctdb_context *ctdb)
{
        struct ctdb_tcp *ctcp = talloc_get_type(ctdb->transport_data,
                                                struct ctdb_tcp);
        ctdb_sock_addr sock;
        int lock_fd;
        unsigned int i;
        const char *lock_path = CTDB_RUNDIR "/.socket_lock";
        struct flock lock;
        int one = 1;
        int sock_size;
        struct tevent_fd *fde;

        /* If there are no nodes, then it won't be possible to find
         * the first one.  Log a failure and short circuit the whole
         * process.
         */
        if (ctdb->num_nodes == 0) {
                DEBUG(DEBUG_CRIT,("No nodes available to attempt bind to - is the nodes file empty?\n"));
                return -1;
        }

        /* in order to ensure that we don't get two nodes with the
           same address, we must make the bind() and listen() calls
           atomic. The SO_REUSEADDR setsockopt only prevents double
           binds if the first socket is in LISTEN state  */
        lock_fd = open(lock_path, O_RDWR|O_CREAT, 0666);
        if (lock_fd == -1) {
                DEBUG(DEBUG_CRIT,("Unable to open %s\n", lock_path));
                return -1;
        }

        lock.l_type = F_WRLCK;
        lock.l_whence = SEEK_SET;
        lock.l_start = 0;
        lock.l_len = 1;
        lock.l_pid = 0;

        if (fcntl(lock_fd, F_SETLKW, &lock) != 0) {
                DEBUG(DEBUG_CRIT,("Unable to lock %s\n", lock_path));
                close(lock_fd);
                return -1;
        }

        for (i=0; i < ctdb->num_nodes; i++) {
                if (ctdb->nodes[i]->flags & NODE_FLAGS_DELETED) {
                        continue;
                }
                sock = ctdb->nodes[i]->address;

                switch (sock.sa.sa_family) {
                case AF_INET:
                        sock_size = sizeof(sock.ip);
                        break;
                case AF_INET6:
                        sock_size = sizeof(sock.ip6);
                        break;
                default:
                        DEBUG(DEBUG_ERR, (__location__ " unknown family %u\n",
                                sock.sa.sa_family));
                        continue;
                }

                ctcp->listen_fd = socket(sock.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
                if (ctcp->listen_fd == -1) {
                        ctdb_set_error(ctdb, "socket failed\n");
                        continue;
                }

                set_close_on_exec(ctcp->listen_fd);

                if (setsockopt(ctcp->listen_fd,SOL_SOCKET,SO_REUSEADDR,
                               (char *)&one,sizeof(one)) == -1) {
                        DEBUG(DEBUG_WARNING, ("Failed to set REUSEADDR on fd - %s\n",
                                              strerror(errno)));
                }

                if (bind(ctcp->listen_fd, (struct sockaddr * )&sock, sock_size) == 0) {
                        break;
                }

                if (errno == EADDRNOTAVAIL) {
                        DEBUG(DEBUG_DEBUG,(__location__ " Failed to bind() to socket. %s(%d)\n",
                                        strerror(errno), errno));
                } else {
                        DEBUG(DEBUG_ERR,(__location__ " Failed to bind() to socket. %s(%d)\n",
                                        strerror(errno), errno));
                }

                close(ctcp->listen_fd);
                ctcp->listen_fd = -1;
        }

        if (i == ctdb->num_nodes) {
                DEBUG(DEBUG_CRIT,("Unable to bind to any of the node addresses - giving up\n"));
                goto failed;
        }
        ctdb->address = talloc_memdup(ctdb,
                                      &ctdb->nodes[i]->address,
                                      sizeof(ctdb_sock_addr));
        if (ctdb->address == NULL) {
                ctdb_set_error(ctdb, "Out of memory at %s:%d",
                               __FILE__, __LINE__);
                goto failed;
        }

        ctdb->name = talloc_asprintf(ctdb, "%s:%u",
                                     ctdb_addr_to_str(ctdb->address),
                                     ctdb_addr_to_port(ctdb->address));
        if (ctdb->name == NULL) {
                ctdb_set_error(ctdb, "Out of memory at %s:%d",
                               __FILE__, __LINE__);
                goto failed;
        }
        DEBUG(DEBUG_INFO,("ctdb chose network address %s\n", ctdb->name));

        if (listen(ctcp->listen_fd, 10) == -1) {
                goto failed;
        }

        fde = tevent_add_fd(ctdb->ev, ctcp, ctcp->listen_fd, TEVENT_FD_READ,
                            ctdb_listen_event, ctdb);
        tevent_fd_set_auto_close(fde);

        close(lock_fd);

        return 0;

failed:
        close(lock_fd);
        if (ctcp->listen_fd != -1) {
                close(ctcp->listen_fd);
                ctcp->listen_fd = -1;
        }
        return -1;
}


/*
  listen on our own address
*/
int ctdb_tcp_listen(struct ctdb_context *ctdb)
{
        struct ctdb_tcp *ctcp = talloc_get_type(ctdb->transport_data,
                                                struct ctdb_tcp);
        ctdb_sock_addr sock;
        int sock_size;
        int one = 1;
        struct tevent_fd *fde;

        /* we can either auto-bind to the first available address, or we can
           use a specified address */
        if (!ctdb->address) {
                return ctdb_tcp_listen_automatic(ctdb);
        }

        sock = *ctdb->address;

        switch (sock.sa.sa_family) {
        case AF_INET:
                sock_size = sizeof(sock.ip);
                break;
        case AF_INET6:
                sock_size = sizeof(sock.ip6);
                break;
        default:
                DEBUG(DEBUG_ERR, (__location__ " unknown family %u\n",
                        sock.sa.sa_family));
                goto failed;
        }

        ctcp->listen_fd = socket(sock.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
        if (ctcp->listen_fd == -1) {
                ctdb_set_error(ctdb, "socket failed\n");
                return -1;
        }

        set_close_on_exec(ctcp->listen_fd);

        if (setsockopt(ctcp->listen_fd,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(one)) == -1) {
                DEBUG(DEBUG_WARNING, ("Failed to set REUSEADDR on fd - %s\n",
                                      strerror(errno)));
        }

        if (bind(ctcp->listen_fd, (struct sockaddr * )&sock, sock_size) != 0) {
                DEBUG(DEBUG_ERR,(__location__ " Failed to bind() to socket. %s(%d)\n", strerror(errno), errno));
                goto failed;
        }

        if (listen(ctcp->listen_fd, 10) == -1) {
                goto failed;
        }

        fde = tevent_add_fd(ctdb->ev, ctcp, ctcp->listen_fd, TEVENT_FD_READ,
                            ctdb_listen_event, ctdb);
        tevent_fd_set_auto_close(fde);

        return 0;

failed:
        if (ctcp->listen_fd != -1) {
                close(ctcp->listen_fd);
        }
        ctcp->listen_fd = -1;
        return -1;
}