Logo Search packages:      
Sourcecode: glibc version File versions

rcmd.c

/*
 * Copyright (C) 1998 WIDE Project.
 * 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. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
 */
/*
 * Copyright (c) 1983, 1993, 1994
 *    The Regents of the University of California.  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.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)rcmd.c  8.3 (Berkeley) 3/26/94";
#endif /* LIBC_SCCS and not lint */

#include <sys/param.h>
#include <sys/poll.h>
#include <sys/socket.h>
#include <sys/stat.h>

#include <netinet/in.h>
#include <arpa/inet.h>

#include <alloca.h>
#include <signal.h>
#include <fcntl.h>
#include <netdb.h>
#include <unistd.h>
#include <pwd.h>
#include <errno.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <ctype.h>
#include <string.h>
#include <libintl.h>
#include <stdlib.h>
#ifdef USE_IN_LIBIO
# include <wchar.h>
#endif
#include <sys/uio.h>


int __ivaliduser (FILE *, u_int32_t, const char *, const char *);
static int __validuser2_sa (FILE *, struct sockaddr *, size_t,
                      const char *, const char *, const char *);
static int ruserok2_sa (struct sockaddr *ra, size_t ralen,
                  int superuser, const char *ruser,
                  const char *luser, const char *rhost);
static int ruserok_sa (struct sockaddr *ra, size_t ralen,
                  int superuser, const char *ruser,
                  const char *luser);
int iruserok_af (const void *raddr, int superuser, const char *ruser,
             const char *luser, sa_family_t af);
int iruserok (u_int32_t raddr, int superuser, const char *ruser,
            const char *luser);

libc_hidden_proto (iruserok_af)

libc_freeres_ptr(static char *ahostbuf);

int
rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, af)
      char **ahost;
      u_short rport;
      const char *locuser, *remuser, *cmd;
      int *fd2p;
      sa_family_t af;
{
      char paddr[INET6_ADDRSTRLEN];
      struct addrinfo hints, *res, *ai;
      struct sockaddr_storage from;
      struct pollfd pfd[2];
      int32_t oldmask;
      pid_t pid;
      int s, lport, timo, error;
      char c;
      int refused;
      char num[8];
      ssize_t n;

      if (af != AF_INET && af != AF_INET6 && af != AF_UNSPEC)
        {
          __set_errno (EAFNOSUPPORT);
          return -1;
        }

      pid = __getpid();

      memset(&hints, '\0', sizeof(hints));
      hints.ai_flags = AI_CANONNAME;
      hints.ai_family = af;
      hints.ai_socktype = SOCK_STREAM;
      (void)__snprintf(num, sizeof(num), "%d", ntohs(rport));
      error = getaddrinfo(*ahost, num, &hints, &res);
      if (error) {
#ifdef USE_IN_LIBIO
            if (_IO_fwide (stderr, 0) > 0)
                  __fwprintf(stderr, L"rcmd: getaddrinfo: %s\n",
                           gai_strerror(error));
            else
#endif
                  fprintf(stderr, "rcmd: getaddrinfo: %s\n",
                        gai_strerror(error));
                return (-1);
      }

      pfd[0].events = POLLIN;
      pfd[1].events = POLLIN;

      if (res->ai_canonname){
            free (ahostbuf);
            ahostbuf = strdup (res->ai_canonname);
            if (ahostbuf == NULL) {
#ifdef USE_IN_LIBIO
                  if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf(stderr, L"%s",
                                 _("rcmd: Cannot allocate memory\n"));
                  else
#endif
                        fputs(_("rcmd: Cannot allocate memory\n"),
                              stderr);
                  return (-1);
            }
            *ahost = ahostbuf;
      } else
            *ahost = NULL;
      ai = res;
      refused = 0;
      oldmask = __sigblock(sigmask(SIGURG));
      for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
            char errbuf[200];

            s = rresvport_af(&lport, ai->ai_family);
            if (s < 0) {
                  if (errno == EAGAIN) {
#ifdef USE_IN_LIBIO
                        if (_IO_fwide (stderr, 0) > 0)
                              __fwprintf(stderr, L"%s",
                                       _("rcmd: socket: All ports in use\n"));
                        else
#endif
                              fputs(_("rcmd: socket: All ports in use\n"),
                                    stderr);
                  } else {
#ifdef USE_IN_LIBIO
                        if (_IO_fwide (stderr, 0) > 0)
                              __fwprintf(stderr,
                                       L"rcmd: socket: %m\n");
                        else
#endif
                              fprintf(stderr, "rcmd: socket: %m\n");
                  }
                  __sigsetmask(oldmask);
                  freeaddrinfo(res);
                  return -1;
            }
            __fcntl(s, F_SETOWN, pid);
            if (__connect(s, ai->ai_addr, ai->ai_addrlen) >= 0)
                  break;
            (void)__close(s);
            if (errno == EADDRINUSE) {
                  lport--;
                  continue;
            }
            if (errno == ECONNREFUSED)
                  refused = 1;
            if (ai->ai_next != NULL) {
                  int oerrno = errno;
                  char *buf = NULL;

                  getnameinfo(ai->ai_addr, ai->ai_addrlen,
                            paddr, sizeof(paddr),
                            NULL, 0,
                            NI_NUMERICHOST);

                  if (__asprintf (&buf, _("connect to address %s: "),
                              paddr) >= 0)
                    {
#ifdef USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf(stderr, L"%s", buf);
                      else
#endif
                        fputs (buf, stderr);
                      free (buf);
                    }
                  __set_errno (oerrno);
                  perror(0);
                  ai = ai->ai_next;
                  getnameinfo(ai->ai_addr, ai->ai_addrlen,
                            paddr, sizeof(paddr),
                            NULL, 0,
                            NI_NUMERICHOST);
                  if (__asprintf (&buf, _("Trying %s...\n"), paddr) >= 0)
                    {
#ifdef USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf (stderr, L"%s", buf);
                      else
#endif
                        fputs (buf, stderr);
                      free (buf);
                    }
                  continue;
            }
            if (refused && timo <= 16) {
                  (void)__sleep(timo);
                  timo *= 2;
                  ai = res;
                  refused = 0;
                  continue;
            }
            freeaddrinfo(res);
#ifdef USE_IN_LIBIO
            if (_IO_fwide (stderr, 0) > 0)
                  (void)__fwprintf(stderr, L"%s: %s\n", *ahost,
                               __strerror_r(errno,
                                          errbuf, sizeof (errbuf)));
            else
#endif
                  (void)fprintf(stderr, "%s: %s\n", *ahost,
                              __strerror_r(errno,
                                       errbuf, sizeof (errbuf)));
            __sigsetmask(oldmask);
            return -1;
      }
      lport--;
      if (fd2p == 0) {
            __write(s, "", 1);
            lport = 0;
      } else {
            char num[8];
            int s2 = rresvport_af(&lport, ai->ai_family), s3;
            socklen_t len = ai->ai_addrlen;

            if (s2 < 0)
                  goto bad;
            __listen(s2, 1);
            (void)__snprintf(num, sizeof(num), "%d", lport);
            if (__write(s, num, strlen(num)+1) != (ssize_t)strlen(num)+1) {
                  char *buf = NULL;

                  if (__asprintf (&buf, _("\
rcmd: write (setting up stderr): %m\n")) >= 0)
                    {
#ifdef USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf(stderr, L"%s", buf);
                      else
#endif
                        fputs (buf, stderr);
                      free (buf);
                    }
                  (void)__close(s2);
                  goto bad;
            }
            pfd[0].fd = s;
            pfd[1].fd = s2;
            __set_errno (0);
            if (__poll (pfd, 2, -1) < 1 || (pfd[1].revents & POLLIN) == 0){
                  char *buf = NULL;

                  if ((errno != 0
                       && __asprintf(&buf, _("\
rcmd: poll (setting up stderr): %m\n")) >= 0)
                      || (errno == 0
                        && __asprintf(&buf, _("\
poll: protocol failure in circuit setup\n")) >= 0))
                    {
#ifdef USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf (stderr, L"%s", buf);
                      else
#endif
                        fputs (buf, stderr);
                      free  (buf);
                    }
                  (void)__close(s2);
                  goto bad;
            }
            s3 = TEMP_FAILURE_RETRY (accept(s2, (struct sockaddr *)&from,
                                    &len));
            switch (from.ss_family) {
            case AF_INET:
                  rport = ntohs(((struct sockaddr_in *)&from)->sin_port);
                  break;
            case AF_INET6:
                  rport = ntohs(((struct sockaddr_in6 *)&from)->sin6_port);
                  break;
            default:
                  rport = 0;
                  break;
            }
            (void)__close(s2);
            if (s3 < 0) {
#ifdef USE_IN_LIBIO
                  if (_IO_fwide (stderr, 0) > 0)
                        (void)__fwprintf(stderr,
                                     L"rcmd: accept: %m\n");
                  else
#endif
                        (void)fprintf(stderr,
                                    "rcmd: accept: %m\n");
                  lport = 0;
                  goto bad;
            }
            *fd2p = s3;

            if (rport >= IPPORT_RESERVED || rport < IPPORT_RESERVED / 2){
                  char *buf = NULL;

                  if (__asprintf(&buf, _("\
socket: protocol failure in circuit setup\n")) >= 0)
                    {
#ifdef USE_IN_LIBIO
                      if (_IO_fwide (stderr, 0) > 0)
                        __fwprintf (stderr, L"%s", buf);
                      else
#endif
                        fputs (buf, stderr);
                      free (buf);
                    }
                  goto bad2;
            }
      }
      struct iovec iov[3] =
        {
          [0] = { .iov_base = (void *) locuser,
                .iov_len = strlen (locuser) + 1 },
          [1] = { .iov_base = (void *) remuser,
                .iov_len = strlen (remuser) + 1 },
          [2] = { .iov_base = (void *) cmd,
                .iov_len = strlen (cmd) + 1 }
        };
      (void) TEMP_FAILURE_RETRY (__writev (s, iov, 3));
      n = TEMP_FAILURE_RETRY (__read(s, &c, 1));
      if (n != 1) {
            char *buf = NULL;

            if ((n == 0
                 && __asprintf(&buf, _("rcmd: %s: short read"),
                           *ahost) >= 0)
                || (n != 0
                  && __asprintf(&buf, "rcmd: %s: %m\n", *ahost) >= 0))
              {
#ifdef USE_IN_LIBIO
                if (_IO_fwide (stderr, 0) > 0)
                  __fwprintf (stderr, L"%s", buf);
                else
#endif
                  fputs (buf, stderr);
                free (buf);
              }
            goto bad2;
      }
      if (c != 0) {
            while (__read(s, &c, 1) == 1) {
                  (void)__write(STDERR_FILENO, &c, 1);
                  if (c == '\n')
                        break;
            }
            goto bad2;
      }
      __sigsetmask(oldmask);
      freeaddrinfo(res);
      return s;
bad2:
      if (lport)
            (void)__close(*fd2p);
bad:
      (void)__close(s);
      __sigsetmask(oldmask);
      freeaddrinfo(res);
      return -1;
}
libc_hidden_def (rcmd_af)

int
rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
      char **ahost;
      u_short rport;
      const char *locuser, *remuser, *cmd;
      int *fd2p;
{
  return rcmd_af (ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
}

int
rresvport_af(alport, family)
      int *alport;
      sa_family_t family;
{
      struct sockaddr_storage ss;
      int s;
      size_t len;
      uint16_t *sport;

      switch(family){
      case AF_INET:
            len = sizeof(struct sockaddr_in);
            sport = &((struct sockaddr_in *)&ss)->sin_port;
            break;
      case AF_INET6:
            len = sizeof(struct sockaddr_in6);
            sport = &((struct sockaddr_in6 *)&ss)->sin6_port;
            break;
      default:
            __set_errno (EAFNOSUPPORT);
            return -1;
      }
      s = __socket(family, SOCK_STREAM, 0);
      if (s < 0)
            return -1;

      memset (&ss, '\0', sizeof(ss));
#ifdef SALEN
      ss.__ss_len = len;
#endif
      ss.ss_family = family;

      /* Ignore invalid values.  */
      if (*alport < IPPORT_RESERVED / 2)
            *alport = IPPORT_RESERVED / 2;
      else if (*alport >= IPPORT_RESERVED)
            *alport = IPPORT_RESERVED - 1;

      int start = *alport;
      do {
            *sport = htons((uint16_t) *alport);
            if (__bind(s, (struct sockaddr *)&ss, len) >= 0)
                  return s;
            if (errno != EADDRINUSE) {
                  (void)__close(s);
                  return -1;
            }
            if ((*alport)-- == IPPORT_RESERVED/2)
                  *alport = IPPORT_RESERVED - 1;
      } while (*alport != start);
      (void)__close(s);
      __set_errno (EAGAIN);
      return -1;
}
libc_hidden_def (rresvport_af)

int
rresvport(alport)
      int *alport;
{
      return rresvport_af(alport, AF_INET);
}

int   __check_rhosts_file = 1;
char  *__rcmd_errstr;

int
ruserok_af(rhost, superuser, ruser, luser, af)
      const char *rhost, *ruser, *luser;
      int superuser;
      sa_family_t af;
{
      struct addrinfo hints, *res, *res0;
      int gai;
      int ret;

      memset (&hints, '\0', sizeof(hints));
      hints.ai_family = af;
      gai = getaddrinfo(rhost, NULL, &hints, &res0);
      if (gai)
            return -1;
      ret = -1;
      for (res=res0; res; res=res->ai_next)
            if (ruserok2_sa(res->ai_addr, res->ai_addrlen,
                        superuser, ruser, luser, rhost) == 0){
                  ret = 0;
                  break;
            }
      freeaddrinfo(res0);
      return (ret);
}
libc_hidden_def (ruserok_af)

int
ruserok(rhost, superuser, ruser, luser)
      const char *rhost, *ruser, *luser;
      int superuser;
{
      return ruserok_af(rhost, superuser, ruser, luser, AF_INET);
}

/* Extremely paranoid file open function. */
static FILE *
iruserfopen (const char *file, uid_t okuser)
{
  struct stat64 st;
  char *cp = NULL;
  FILE *res = NULL;

  /* If not a regular file, if owned by someone other than user or
     root, if writeable by anyone but the owner, or if hardlinked
     anywhere, quit.  */
  cp = NULL;
  if (__lxstat64 (_STAT_VER, file, &st))
    cp = _("lstat failed");
  else if (!S_ISREG (st.st_mode))
    cp = _("not regular file");
  else
    {
      res = fopen (file, "r");
      if (!res)
      cp = _("cannot open");
      else if (__fxstat64 (_STAT_VER, fileno (res), &st) < 0)
      cp = _("fstat failed");
      else if (st.st_uid && st.st_uid != okuser)
      cp = _("bad owner");
      else if (st.st_mode & (S_IWGRP|S_IWOTH))
      cp = _("writeable by other than owner");
      else if (st.st_nlink > 1)
      cp = _("hard linked somewhere");
    }

  /* If there were any problems, quit.  */
  if (cp != NULL)
    {
      __rcmd_errstr = cp;
      if (res)
      fclose (res);
      return NULL;
    }

  /* No threads use this stream.  */
  __fsetlocking (res, FSETLOCKING_BYCALLER);

  return res;
}

/*
 * New .rhosts strategy: We are passed an ip address. We spin through
 * hosts.equiv and .rhosts looking for a match. When the .rhosts only
 * has ip addresses, we don't have to trust a nameserver.  When it
 * contains hostnames, we spin through the list of addresses the nameserver
 * gives us and look for a match.
 *
 * Returns 0 if ok, -1 if not ok.
 */
static int
ruserok2_sa (ra, ralen, superuser, ruser, luser, rhost)
     struct sockaddr *ra;
     size_t ralen;
     int superuser;
     const char *ruser, *luser, *rhost;
{
  FILE *hostf = NULL;
  int isbad = -1;

  if (!superuser)
    hostf = iruserfopen (_PATH_HEQUIV, 0);

  if (hostf)
    {
      isbad = __validuser2_sa (hostf, ra, ralen, luser, ruser, rhost);
      fclose (hostf);

      if (!isbad)
      return 0;
    }

  if (__check_rhosts_file || superuser)
    {
      char *pbuf;
      struct passwd pwdbuf, *pwd;
      size_t dirlen;
      size_t buflen = __sysconf (_SC_GETPW_R_SIZE_MAX);
      char *buffer = __alloca (buflen);
      uid_t uid;

      if (__getpwnam_r (luser, &pwdbuf, buffer, buflen, &pwd) != 0
        || pwd == NULL)
      return -1;

      dirlen = strlen (pwd->pw_dir);
      pbuf = alloca (dirlen + sizeof "/.rhosts");
      __mempcpy (__mempcpy (pbuf, pwd->pw_dir, dirlen),
             "/.rhosts", sizeof "/.rhosts");

       /* Change effective uid while reading .rhosts.  If root and
        reading an NFS mounted file system, can't read files that
        are protected read/write owner only.  */
       uid = __geteuid ();
       seteuid (pwd->pw_uid);
       hostf = iruserfopen (pbuf, pwd->pw_uid);

       if (hostf != NULL)
       {
           isbad = __validuser2_sa (hostf, ra, ralen, luser, ruser, rhost);
           fclose (hostf);
       }

       seteuid (uid);
       return isbad;
    }
  return -1;
}
/*
 * ruserok_sa() is now discussed on ipng, so
 * currently disabled for external use
 */
static int ruserok_sa(ra, ralen, superuser, ruser, luser)
     struct sockaddr *ra;
     size_t ralen;
     int superuser;
     const char *ruser, *luser;
{
  return ruserok2_sa(ra, ralen, superuser, ruser, luser, "-");
}

/* This is the exported version.  */
int
iruserok_af (raddr, superuser, ruser, luser, af)
     const void *raddr;
     int superuser;
     const char *ruser, *luser;
     sa_family_t af;
{
  struct sockaddr_storage ra;
  size_t ralen;

  memset (&ra, '\0', sizeof(ra));
  switch (af){
  case AF_INET:
    ((struct sockaddr_in *)&ra)->sin_family = AF_INET;
    memcpy (&(((struct sockaddr_in *)&ra)->sin_addr), raddr,
          sizeof(struct in_addr));
    ralen = sizeof(struct sockaddr_in);
    break;
  case AF_INET6:
    ((struct sockaddr_in6 *)&ra)->sin6_family = AF_INET6;
    memcpy (&(((struct sockaddr_in6 *)&ra)->sin6_addr), raddr,
            sizeof(struct in6_addr));
    ralen = sizeof(struct sockaddr_in6);
    break;
  default:
    return 0;
  }
  return ruserok_sa ((struct sockaddr *)&ra, ralen, superuser, ruser, luser);
}
libc_hidden_def (iruserok_af)

int
iruserok (raddr, superuser, ruser, luser)
     u_int32_t raddr;
     int superuser;
     const char *ruser, *luser;
{
  return iruserok_af (&raddr, superuser, ruser, luser, AF_INET);
}

/*
 * XXX
 * Don't make static, used by lpd(8).
 *
 * This function is not used anymore. It is only present because lpd(8)
 * calls it (!?!). We simply call __invaliduser2() with an illegal rhost
 * argument. This means that netgroups won't work in .rhost/hosts.equiv
 * files. If you want lpd to work with netgroups, fix lpd to use ruserok()
 * or PAM.
 * Returns 0 if ok, -1 if not ok.
 */
int
__ivaliduser(hostf, raddr, luser, ruser)
      FILE *hostf;
      u_int32_t raddr;
      const char *luser, *ruser;
{
      struct sockaddr_in ra;
      memset(&ra, '\0', sizeof(ra));
      ra.sin_family = AF_INET;
      ra.sin_addr.s_addr = raddr;
      return __validuser2_sa(hostf, (struct sockaddr *)&ra, sizeof(ra),
                         luser, ruser, "-");
}


/* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
static int
internal_function
__checkhost_sa (struct sockaddr *ra, size_t ralen, char *lhost,
            const char *rhost)
{
      struct addrinfo hints, *res0, *res;
      char raddr[INET6_ADDRSTRLEN];
      int match;
      int negate=1;    /* Multiply return with this to get -1 instead of 1 */

      /* Check nis netgroup.  */
      if (strncmp ("+@", lhost, 2) == 0)
            return innetgr (&lhost[2], rhost, NULL, NULL);

      if (strncmp ("-@", lhost, 2) == 0)
            return -innetgr (&lhost[2], rhost, NULL, NULL);

      /* -host */
      if (strncmp ("-", lhost,1) == 0) {
            negate = -1;
            lhost++;
      } else if (strcmp ("+",lhost) == 0) {
            return 1;                    /* asking for trouble, but ok.. */
      }

      /* Try for raw ip address first. */
      /* XXX */
      if (getnameinfo(ra, ralen,
                  raddr, sizeof(raddr), NULL, 0,
                  NI_NUMERICHOST) == 0
          && strcmp(raddr, lhost) == 0)
            return negate;

      /* Better be a hostname. */
      match = 0;
      memset(&hints, '\0', sizeof(hints));
      hints.ai_family = ra->sa_family;
      if (getaddrinfo(lhost, NULL, &hints, &res0) == 0){
            /* Spin through ip addresses. */
            for (res = res0; res; res = res->ai_next)
              {
                if (res->ai_family == ra->sa_family
                  && !memcmp(res->ai_addr, ra, res->ai_addrlen))
                  {
                  match = 1;
                  break;
                  }
              }
            freeaddrinfo (res0);
      }
      return negate * match;
}

/* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
static int
internal_function
__icheckuser (const char *luser, const char *ruser)
{
    /*
      luser is user entry from .rhosts/hosts.equiv file
      ruser is user id on remote host
      */

    /* [-+]@netgroup */
    if (strncmp ("+@", luser, 2) == 0)
      return innetgr (&luser[2], NULL, ruser, NULL);

    if (strncmp ("-@", luser,2) == 0)
      return -innetgr (&luser[2], NULL, ruser, NULL);

    /* -user */
    if (strncmp ("-", luser, 1) == 0)
      return -(strcmp (&luser[1], ruser) == 0);

    /* + */
    if (strcmp ("+", luser) == 0)
      return 1;

    /* simple string match */
    return strcmp (ruser, luser) == 0;
}

/*
 * Returns 1 for blank lines (or only comment lines) and 0 otherwise
 */
static int
__isempty (char *p)
{
    while (*p && isspace (*p)) {
      ++p;
    }

    return (*p == '\0' || *p == '#') ? 1 : 0 ;
}

/*
 * Returns 0 if positive match, -1 if _not_ ok.
 */
static int
__validuser2_sa(hostf, ra, ralen, luser, ruser, rhost)
      FILE *hostf;
      struct sockaddr *ra;
      size_t ralen;
      const char *luser, *ruser, *rhost;
{
    register const char *user;
    register char *p;
    int hcheck, ucheck;
    char *buf = NULL;
    size_t bufsize = 0;
    int retval = -1;

    while (__getline (&buf, &bufsize, hostf) > 0) {
      buf[bufsize - 1] = '\0'; /* Make sure it's terminated.  */
        p = buf;

      /* Skip empty or comment lines */
      if (__isempty (p)) {
          continue;
      }

      /* Skip lines that are too long. */
      if (strchr (p, '\n') == NULL) {
          int ch = getc_unlocked (hostf);

          while (ch != '\n' && ch != EOF)
            ch = getc_unlocked (hostf);
          continue;
      }

      for (;*p && !isspace(*p); ++p) {
          *p = _tolower (*p);
      }

      /* Next we want to find the permitted name for the remote user.  */
      if (*p == ' ' || *p == '\t') {
          /* <nul> terminate hostname and skip spaces */
          for (*p++='\0'; *p && isspace (*p); ++p);

          user = p;                   /* this is the user's name */
          while (*p && !isspace (*p))
            ++p;                    /* find end of user's name */
      } else
          user = p;

      *p = '\0';              /* <nul> terminate username (+host?) */

      /* buf -> host(?) ; user -> username(?) */

      /* First check host part */
      hcheck = __checkhost_sa (ra, ralen, buf, rhost);

      if (hcheck < 0)
          break;

      if (hcheck) {
          /* Then check user part */
          if (! (*user))
            user = luser;

          ucheck = __icheckuser (user, ruser);

          /* Positive 'host user' match? */
          if (ucheck > 0) {
            retval = 0;
            break;
          }

          /* Negative 'host -user' match? */
          if (ucheck < 0)
            break;

          /* Neither, go on looking for match */
      }
    }

    if (buf != NULL)
      free (buf);

    return retval;
}

Generated by  Doxygen 1.6.0   Back to index