/*-
 * SPDX-License-Identifier: BSD-4-Clause
 *
 * Copyright (c) 1995
 *      A.R. Gordon (andrew.gordon@net-tel.co.uk).  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed for the FreeBSD project
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ANDREW GORDON AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

/* main() function for status monitor daemon.  Some of the code in this */
/* file was generated by running rpcgen /usr/include/rpcsvc/sm_inter.x  */
/* The actual program logic is in the file procs.c                      */

#include <sys/cdefs.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <rpc/rpc.h>
#include <rpc/rpc_com.h>
#include <string.h>
#include <syslog.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <signal.h>
#include <unistd.h>
#include "statd.h"

#define GETPORT_MAXTRY  20      /* Max tries to get a port # */

int debug = 0;          /* Controls syslog() calls for debug messages   */

static char **hosts, *svcport_str = NULL;
static int nhosts = 0;
static int xcreated = 0;
static int      mallocd_svcport = 0;
static int      *sock_fd;
static int      sock_fdcnt;
static int      sock_fdpos;

static int      create_service(struct netconfig *nconf);
static void     complete_service(struct netconfig *nconf, char *port_str);
static void     clearout_service(void);
static void handle_sigchld(int sig);
void out_of_mem(void) __dead2;

static void usage(void) __dead2;

int
main(int argc, char **argv)
{
  struct sigaction sa;
  struct netconfig *nconf;
  void *nc_handle;
  in_port_t svcport;
  int ch, i, s;
  char *endptr;
  char **hosts_bak;
  int have_v6 = 1;
  int foreground = 0;
  int maxrec = RPC_MAXDATASIZE;
  int attempt_cnt, port_len, port_pos, ret;
  char **port_list;

  while ((ch = getopt(argc, argv, "dFh:p:")) != -1)
    switch (ch) {
    case 'd':
      debug = 1;
      break;
    case 'F':
      foreground = 1;
      break;
    case 'h':
      ++nhosts;
      hosts_bak = hosts;
      hosts_bak = realloc(hosts, nhosts * sizeof(char *));
      if (hosts_bak == NULL) {
              if (hosts != NULL) {
                      for (i = 0; i < nhosts; i++) 
                              free(hosts[i]);
                      free(hosts);
                      out_of_mem();
              }
      }
      hosts = hosts_bak;
      hosts[nhosts - 1] = strdup(optarg);
      if (hosts[nhosts - 1] == NULL) {
              for (i = 0; i < (nhosts - 1); i++) 
                      free(hosts[i]);
              free(hosts);
              out_of_mem();
      }
      break;
    case 'p':
      endptr = NULL;
      svcport = (in_port_t)strtoul(optarg, &endptr, 10);
      if (endptr == NULL || *endptr != '\0' || svcport == 0 || 
          svcport >= IPPORT_MAX)
        usage();
      
      svcport_str = strdup(optarg);
      break;
    default:
      usage();
    }
  argc -= optind;
  argv += optind;

  (void)rpcb_unset(SM_PROG, SM_VERS, NULL);

  /*
   * Check if IPv6 support is present.
   */
  s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
  if (s < 0)
      have_v6 = 0;
  else 
      close(s);

  rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrec);

  /*
   * If no hosts were specified, add a wildcard entry to bind to
   * INADDR_ANY. Otherwise make sure 127.0.0.1 and ::1 are added to the
   * list.
   */
  if (nhosts == 0) {
          hosts = malloc(sizeof(char *));
          if (hosts == NULL)
                  out_of_mem();

          hosts[0] = strdup("*");
          nhosts = 1;
  } else {
          hosts_bak = hosts;
          if (have_v6) {
                  hosts_bak = realloc(hosts, (nhosts + 2) *
                      sizeof(char *));
                  if (hosts_bak == NULL) {
                          for (i = 0; i < nhosts; i++)
                                  free(hosts[i]);
                          free(hosts);
                          out_of_mem();
                  } else
                          hosts = hosts_bak;

                  nhosts += 2;
                  hosts[nhosts - 2] = strdup("::1");
          } else {
                  hosts_bak = realloc(hosts, (nhosts + 1) * sizeof(char *));
                  if (hosts_bak == NULL) {
                          for (i = 0; i < nhosts; i++)
                                  free(hosts[i]);

                          free(hosts);
                          out_of_mem();
                  } else {
                          nhosts += 1;
                          hosts = hosts_bak;
                  }
          }
          hosts[nhosts - 1] = strdup("127.0.0.1");
  }

  attempt_cnt = 1;
  sock_fdcnt = 0;
  sock_fd = NULL;
  port_list = NULL;
  port_len = 0;
  nc_handle = setnetconfig();
  while ((nconf = getnetconfig(nc_handle))) {
          /* We want to listen only on udp6, tcp6, udp, tcp transports */
          if (nconf->nc_flag & NC_VISIBLE) {
                  /* Skip if there's no IPv6 support */
                  if (have_v6 == 0 && strcmp(nconf->nc_protofmly, "inet6") == 0) {
              /* DO NOTHING */
                  } else {
                        ret = create_service(nconf);
                        if (ret == 1)
                                /* Ignore this call */
                                continue;
                        if (ret < 0) {
                                /*
                                 * Failed to bind port, so close off
                                 * all sockets created and try again
                                 * if the port# was dynamically
                                 * assigned via bind(2).
                                 */
                                clearout_service();
                                if (mallocd_svcport != 0 &&
                                    attempt_cnt < GETPORT_MAXTRY) {
                                        free(svcport_str);
                                        svcport_str = NULL;
                                        mallocd_svcport = 0;
                                } else {
                                        errno = EADDRINUSE;
                                        syslog(LOG_ERR,
                                            "bindresvport_sa: %m");
                                        exit(1);
                                }

                                /* Start over at the first service. */
                                free(sock_fd);
                                sock_fdcnt = 0;
                                sock_fd = NULL;
                                nc_handle = setnetconfig();
                                attempt_cnt++;
                        } else if (mallocd_svcport != 0 &&
                            attempt_cnt == GETPORT_MAXTRY) {
                                /*
                                 * For the last attempt, allow
                                 * different port #s for each nconf
                                 * by saving the svcport_str and
                                 * setting it back to NULL.
                                 */
                                port_list = realloc(port_list,
                                    (port_len + 1) * sizeof(char *));
                                if (port_list == NULL)
                                        out_of_mem();
                                port_list[port_len++] = svcport_str;
                                svcport_str = NULL;
                                mallocd_svcport = 0;
                        }
                  }
          }
  }

  /*
   * Successfully bound the ports, so call complete_service() to
   * do the rest of the setup on the service(s).
   */
  sock_fdpos = 0;
  port_pos = 0;
  nc_handle = setnetconfig();
  while ((nconf = getnetconfig(nc_handle))) {
          /* We want to listen only on udp6, tcp6, udp, tcp transports */
          if (nconf->nc_flag & NC_VISIBLE) {
                  /* Skip if there's no IPv6 support */
                  if (have_v6 == 0 && strcmp(nconf->nc_protofmly, "inet6") == 0) {
              /* DO NOTHING */
                  } else if (port_list != NULL) {
                        if (port_pos >= port_len) {
                                syslog(LOG_ERR, "too many port#s");
                                exit(1);
                        }
                        complete_service(nconf, port_list[port_pos++]);
                  } else
                        complete_service(nconf, svcport_str);
          }
  }
  endnetconfig(nc_handle);
  free(sock_fd);
  if (port_list != NULL) {
        for (port_pos = 0; port_pos < port_len; port_pos++)
                free(port_list[port_pos]);
        free(port_list);
  }

  init_file("/var/db/statd.status");

  /* Note that it is NOT sensible to run this program from inetd - the  */
  /* protocol assumes that it will run immediately at boot time.        */
  if ((foreground == 0) && daemon(0, 0) < 0) {
        err(1, "cannot fork");
        /* NOTREACHED */
  }

  openlog("rpc.statd", 0, LOG_DAEMON);
  if (debug) syslog(LOG_INFO, "Starting - debug enabled");
  else syslog(LOG_INFO, "Starting");

  /* Install signal handler to collect exit status of child processes   */
  sa.sa_handler = handle_sigchld;
  sigemptyset(&sa.sa_mask);
  sigaddset(&sa.sa_mask, SIGCHLD);
  sa.sa_flags = SA_RESTART;
  sigaction(SIGCHLD, &sa, NULL);

  /* Initialisation now complete - start operating                      */
  notify_hosts();       /* Forks a process (if necessary) to do the     */
                        /* SM_NOTIFY calls, which may be slow.          */

  svc_run();    /* Should never return                                  */
  exit(1);
}

/*
 * This routine creates and binds sockets on the appropriate
 * addresses. It gets called one time for each transport.
 * It returns 0 upon success, 1 for ignore the call and -1 to indicate
 * bind failed with EADDRINUSE.
 * Any file descriptors that have been created are stored in sock_fd and
 * the total count of them is maintained in sock_fdcnt.
 */
static int
create_service(struct netconfig *nconf)
{
        struct addrinfo hints, *res = NULL;
        struct sockaddr_in *sin;
        struct sockaddr_in6 *sin6;
        struct __rpc_sockinfo si;
        int aicode;
        int fd;
        int nhostsbak;
        int r;
        u_int32_t host_addr[4];  /* IPv4 or IPv6 */
        int mallocd_res;

        if ((nconf->nc_semantics != NC_TPI_CLTS) &&
            (nconf->nc_semantics != NC_TPI_COTS) &&
            (nconf->nc_semantics != NC_TPI_COTS_ORD))
                return (1);     /* not my type */

        /*
         * XXX - using RPC library internal functions.
         */
        if (!__rpc_nconf2sockinfo(nconf, &si)) {
                syslog(LOG_ERR, "cannot get information for %s",
                    nconf->nc_netid);
                return (1);
        }

        /* Get rpc.statd's address on this transport */
        memset(&hints, 0, sizeof hints);
        hints.ai_family = si.si_af;
        hints.ai_socktype = si.si_socktype;
        hints.ai_protocol = si.si_proto;

        /*
         * Bind to specific IPs if asked to
         */
        nhostsbak = nhosts;
        while (nhostsbak > 0) {
                --nhostsbak;
                sock_fd = realloc(sock_fd, (sock_fdcnt + 1) * sizeof(int));
                if (sock_fd == NULL)
                        out_of_mem();
                sock_fd[sock_fdcnt++] = -1;     /* Set invalid for now. */
                mallocd_res = 0;
                hints.ai_flags = AI_PASSIVE;

                /*      
                 * XXX - using RPC library internal functions.
                 */
                if ((fd = __rpc_nconf2fd(nconf)) < 0) {
                        syslog(LOG_ERR, "cannot create socket for %s",
                            nconf->nc_netid);
                        continue;
                }
                switch (hints.ai_family) {
                case AF_INET:
                        if (inet_pton(AF_INET, hosts[nhostsbak],
                            host_addr) == 1) {
                                hints.ai_flags |= AI_NUMERICHOST;
                        } else {
                                /*
                                 * Skip if we have an AF_INET6 address.
                                 */
                                if (inet_pton(AF_INET6, hosts[nhostsbak],
                                    host_addr) == 1) {
                                        close(fd);
                                        continue;
                                }
                        }
                        break;
                case AF_INET6:
                        if (inet_pton(AF_INET6, hosts[nhostsbak],
                            host_addr) == 1) {
                                hints.ai_flags |= AI_NUMERICHOST;
                        } else {
                                /*
                                 * Skip if we have an AF_INET address.
                                 */
                                if (inet_pton(AF_INET, hosts[nhostsbak],
                                    host_addr) == 1) {
                                        close(fd);
                                        continue;
                                }
                        }
                        break;
                default:
                        break;
                }

                /*
                 * If no hosts were specified, just bind to INADDR_ANY
                 */
                if (strcmp("*", hosts[nhostsbak]) == 0) {
                        if (svcport_str == NULL) {
                                res = malloc(sizeof(struct addrinfo));
                                if (res == NULL) 
                                        out_of_mem();
                                mallocd_res = 1;
                                res->ai_flags = hints.ai_flags;
                                res->ai_family = hints.ai_family;
                                res->ai_protocol = hints.ai_protocol;
                                switch (res->ai_family) {
                                case AF_INET:
                                        sin = malloc(sizeof(struct sockaddr_in));
                                        if (sin == NULL) 
                                                out_of_mem();
                                        sin->sin_family = AF_INET;
                                        sin->sin_port = htons(0);
                                        sin->sin_addr.s_addr = htonl(INADDR_ANY);
                                        res->ai_addr = (struct sockaddr*) sin;
                                        res->ai_addrlen = (socklen_t)
                                            sizeof(struct sockaddr_in);
                                        break;
                                case AF_INET6:
                                        sin6 = malloc(sizeof(struct sockaddr_in6));
                                        if (sin6 == NULL)
                                                out_of_mem();
                                        sin6->sin6_family = AF_INET6;
                                        sin6->sin6_port = htons(0);
                                        sin6->sin6_addr = in6addr_any;
                                        res->ai_addr = (struct sockaddr*) sin6;
                                        res->ai_addrlen = (socklen_t)
                                            sizeof(struct sockaddr_in6);
                                        break;
                                default:
                                        syslog(LOG_ERR, "bad addr fam %d",
                                            res->ai_family);
                                        exit(1);
                                }
                        } else { 
                                if ((aicode = getaddrinfo(NULL, svcport_str,
                                    &hints, &res)) != 0) {
                                        syslog(LOG_ERR,
                                            "cannot get local address for %s: %s",
                                            nconf->nc_netid,
                                            gai_strerror(aicode));
                                        close(fd);
                                        continue;
                                }
                        }
                } else {
                        if ((aicode = getaddrinfo(hosts[nhostsbak], svcport_str,
                            &hints, &res)) != 0) {
                                syslog(LOG_ERR,
                                    "cannot get local address for %s: %s",
                                    nconf->nc_netid, gai_strerror(aicode));
                                close(fd);
                                continue;
                        }
                }

                /* Store the fd. */
                sock_fd[sock_fdcnt - 1] = fd;

                /* Now, attempt the bind. */
                r = bindresvport_sa(fd, res->ai_addr);
                if (r != 0) {
                        if (errno == EADDRINUSE && mallocd_svcport != 0) {
                                if (mallocd_res != 0) {
                                        free(res->ai_addr);
                                        free(res);
                                } else
                                        freeaddrinfo(res);
                                return (-1);
                        }
                        syslog(LOG_ERR, "bindresvport_sa: %m");
                        exit(1);
                }

                if (svcport_str == NULL) {
                        svcport_str = malloc(NI_MAXSERV * sizeof(char));
                        if (svcport_str == NULL)
                                out_of_mem();
                        mallocd_svcport = 1;

                        if (getnameinfo(res->ai_addr,
                            res->ai_addr->sa_len, NULL, NI_MAXHOST,
                            svcport_str, NI_MAXSERV * sizeof(char),
                            NI_NUMERICHOST | NI_NUMERICSERV))
                                errx(1, "Cannot get port number");
                }
                if (mallocd_res != 0) {
                        free(res->ai_addr);
                        free(res);
                } else
                        freeaddrinfo(res);
                res = NULL;
        }
        return (0);
}

/*
 * Called after all the create_service() calls have succeeded, to complete
 * the setup and registration.
 */
static void
complete_service(struct netconfig *nconf, char *port_str)
{
        struct addrinfo hints, *res = NULL;
        struct __rpc_sockinfo si;
        struct netbuf servaddr;
        SVCXPRT *transp = NULL;
        int aicode, fd, nhostsbak;
        int registered = 0;

        if ((nconf->nc_semantics != NC_TPI_CLTS) &&
            (nconf->nc_semantics != NC_TPI_COTS) &&
            (nconf->nc_semantics != NC_TPI_COTS_ORD))
                return; /* not my type */

        /*
         * XXX - using RPC library internal functions.
         */
        if (!__rpc_nconf2sockinfo(nconf, &si)) {
                syslog(LOG_ERR, "cannot get information for %s",
                    nconf->nc_netid);
                return;
        }

        nhostsbak = nhosts;
        while (nhostsbak > 0) {
                --nhostsbak;
                if (sock_fdpos >= sock_fdcnt) {
                        /* Should never happen. */
                        syslog(LOG_ERR, "Ran out of socket fd's");
                        return;
                }
                fd = sock_fd[sock_fdpos++];
                if (fd < 0)
                        continue;

                if (nconf->nc_semantics != NC_TPI_CLTS)
                        listen(fd, SOMAXCONN);

                transp = svc_tli_create(fd, nconf, NULL,
                RPC_MAXDATASIZE, RPC_MAXDATASIZE);

                if (transp != (SVCXPRT *) NULL) {
                        if (!svc_register(transp, SM_PROG, SM_VERS,
                            sm_prog_1, 0)) {
                                syslog(LOG_ERR, "can't register on %s",
                                    nconf->nc_netid);
                        } else {
                                if (!svc_reg(transp, SM_PROG, SM_VERS,
                                    sm_prog_1, NULL)) 
                                        syslog(LOG_ERR,
                                            "can't register %s SM_PROG service",
                                            nconf->nc_netid);
                        }
                } else 
                        syslog(LOG_WARNING, "can't create %s services",
                            nconf->nc_netid);

                if (registered == 0) {
                        registered = 1;
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = si.si_af;
                        hints.ai_socktype = si.si_socktype;
                        hints.ai_protocol = si.si_proto;


                        if ((aicode = getaddrinfo(NULL, port_str, &hints,
                            &res)) != 0) {
                                syslog(LOG_ERR, "cannot get local address: %s",
                                    gai_strerror(aicode));
                                exit(1);
                        }

                        servaddr.buf = malloc(res->ai_addrlen);
                        memcpy(servaddr.buf, res->ai_addr, res->ai_addrlen);
                        servaddr.len = res->ai_addrlen;

                        rpcb_set(SM_PROG, SM_VERS, nconf, &servaddr);

                        xcreated++;
                        freeaddrinfo(res);
                }
        } /* end while */
}

/*
 * Clear out sockets after a failure to bind one of them, so that the
 * cycle of socket creation/binding can start anew.
 */
static void
clearout_service(void)
{
        int i;

        for (i = 0; i < sock_fdcnt; i++) {
                if (sock_fd[i] >= 0) {
                        shutdown(sock_fd[i], SHUT_RDWR);
                        close(sock_fd[i]);
                }
        }
}

static void
usage(void)
{
      fprintf(stderr, "usage: rpc.statd [-d] [-F] [-h <bindip>] [-p <port>]\n");
      exit(1);
}

/* handle_sigchld ---------------------------------------------------------- */
/*
   Purpose:     Catch SIGCHLD and collect process status
   Retruns:     Nothing.
   Notes:       No special action required, other than to collect the
                process status and hence allow the child to die:
                we only use child processes for asynchronous transmission
                of SM_NOTIFY to other systems, so it is normal for the
                children to exit when they have done their work.
*/

static void handle_sigchld(int sig __unused)
{
  int pid, status;
  pid = wait4(-1, &status, WNOHANG, (struct rusage*)0);
  if (!pid) syslog(LOG_ERR, "Phantom SIGCHLD??");
  else if (status == 0)
  {
    if (debug) syslog(LOG_DEBUG, "Child %d exited OK", pid);
  }
  else syslog(LOG_ERR, "Child %d failed with status %d", pid,
    WEXITSTATUS(status));
}

/*
 * Out of memory, fatal
 */
void
out_of_mem(void)
{

        syslog(LOG_ERR, "out of memory");
        exit(2);
}