cups/http-addr.c

/*
 * "$Id: http-addr.c 6814 2007-08-20 20:09:25Z mike $"
 *
 *   HTTP address routines for the Common UNIX Printing System (CUPS).
 *
 *   Copyright 2007 by Apple Inc.
 *   Copyright 1997-2006 by Easy Software Products, all rights reserved.
 *
 *   These coded instructions, statements, and computer programs are the
 *   property of Apple Inc. and are protected by Federal copyright
 *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 *   which should have been included with this file.  If this file is
 *   file is missing or damaged, see the license at "http://www.cups.org/".
 *
 * Contents:
 *
 *   httpAddrAny()       - Check for the "any" address.
 *   httpAddrEqual()     - Compare two addresses.
 *   httpAddrLocalhost() - Check for the local loopback address.
 *   httpAddrLookup()    - Lookup the hostname associated with the address.
 *   httpAddrString()    - Convert an IP address to a dotted string.
 *   httpGetHostByName() - Lookup a hostname or IP address, and return
 *                         address records for the specified name.
 *   httpGetHostname()   - Get the FQDN for the local system.
 */

/*
 * Include necessary headers...
 */

#include "globals.h"
#include "debug.h"
#include <stdlib.h>
#include <stddef.h>


/*
 * 'httpAddrAny()' - Check for the "any" address.
 *
 * @since CUPS 1.2@
 */

int					/* O - 1 if "any", 0 otherwise */
httpAddrAny(const http_addr_t *addr)	/* I - Address to check */
{
  if (!addr)
    return (0);

#ifdef AF_INET6
  if (addr->addr.sa_family == AF_INET6 &&
      IN6_IS_ADDR_UNSPECIFIED(&(addr->ipv6.sin6_addr)))
    return (1);
#endif /* AF_INET6 */

  if (addr->addr.sa_family == AF_INET &&
      ntohl(addr->ipv4.sin_addr.s_addr) == 0x00000000)
    return (1);

  return (0);
}


/*
 * 'httpAddrEqual()' - Compare two addresses.
 *
 * @since CUPS 1.2@
 */

int						/* O - 1 if equal, 0 if not */
httpAddrEqual(const http_addr_t *addr1,		/* I - First address */
              const http_addr_t *addr2)		/* I - Second address */
{
  if (!addr1 && !addr2)
    return (1);

  if (!addr1 || !addr2)
    return (0);

  if (addr1->addr.sa_family != addr2->addr.sa_family)
    return (0);

#ifdef AF_LOCAL
  if (addr1->addr.sa_family == AF_LOCAL)
    return (!strcmp(addr1->un.sun_path, addr2->un.sun_path));
#endif /* AF_LOCAL */

#ifdef AF_INET6
  if (addr1->addr.sa_family == AF_INET6)
    return (!memcmp(&(addr1->ipv6.sin6_addr), &(addr2->ipv6.sin6_addr), 16));
#endif /* AF_INET6 */

  return (addr1->ipv4.sin_addr.s_addr == addr2->ipv4.sin_addr.s_addr);
}


/*
 * 'httpAddrLength()' - Return the length of the address in bytes.
 *
 * @since CUPS 1.2@
 */

int					/* O - Length in bytes */
httpAddrLength(const http_addr_t *addr)	/* I - Address */
{
  if (!addr)
    return (0);

#ifdef AF_INET6
  if (addr->addr.sa_family == AF_INET6)
    return (sizeof(addr->ipv6));
  else
#endif /* AF_INET6 */
#ifdef AF_LOCAL
  if (addr->addr.sa_family == AF_LOCAL)
    return (offsetof(struct sockaddr_un, sun_path) +
            strlen(addr->un.sun_path) + 1);
  else
#endif /* AF_LOCAL */
  if (addr->addr.sa_family == AF_INET)
    return (sizeof(addr->ipv4));
  else
    return (0);

}


/*
 * 'httpAddrLocalhost()' - Check for the local loopback address.
 *
 * @since CUPS 1.2@
 */

int					/* O - 1 if local host, 0 otherwise */
httpAddrLocalhost(
    const http_addr_t *addr)		/* I - Address to check */
{
  if (!addr)
    return (1);

#ifdef AF_INET6
  if (addr->addr.sa_family == AF_INET6 &&
      IN6_IS_ADDR_LOOPBACK(&(addr->ipv6.sin6_addr)))
    return (1);
#endif /* AF_INET6 */

#ifdef AF_LOCAL
  if (addr->addr.sa_family == AF_LOCAL)
    return (1);
#endif /* AF_LOCAL */

  if (addr->addr.sa_family == AF_INET &&
      ntohl(addr->ipv4.sin_addr.s_addr) == 0x7f000001)
    return (1);

  return (0);
}


#ifdef __sgi
#  define ADDR_CAST (struct sockaddr *)
#else
#  define ADDR_CAST (char *)
#endif /* __sgi */


/*
 * 'httpAddrLookup()' - Lookup the hostname associated with the address.
 *
 * @since CUPS 1.2@
 */

char *					/* O - Host name */
httpAddrLookup(
    const http_addr_t *addr,		/* I - Address to lookup */
    char              *name,		/* I - Host name buffer */
    int               namelen)		/* I - Size of name buffer */
{
  DEBUG_printf(("httpAddrLookup(addr=%p, name=%p, namelen=%d)\n",
                addr, name, namelen));

 /*
  * Range check input...
  */

  if (!addr || !name || namelen <= 2)
  {
    if (name && namelen >= 1)
      *name = '\0';

    return (NULL);
  }

#ifdef AF_LOCAL
  if (addr->addr.sa_family == AF_LOCAL)
    strlcpy(name, addr->un.sun_path, namelen);
  else
#endif /* AF_LOCAL */
#ifdef HAVE_GETNAMEINFO
  {
   /*
    * STR #2486: httpAddrLookup() fails when getnameinfo() returns EAI_AGAIN
    *
    * FWIW, I think this is really a bug in the implementation of
    * getnameinfo(), but falling back on httpAddrString() is easy to
    * do...
    */

    if (getnameinfo(&addr->addr, httpAddrLength(addr), name, namelen,
		    NULL, 0, 0))
      return (httpAddrString(addr, name, namelen));
  }
#else
  {
    struct hostent	*host;			/* Host from name service */


#  ifdef AF_INET6
    if (addr->addr.sa_family == AF_INET6)
      host = gethostbyaddr(ADDR_CAST &(addr->ipv6.sin6_addr),
                	   sizeof(struct in_addr), AF_INET6);
    else
#  endif /* AF_INET6 */
    host = gethostbyaddr(ADDR_CAST &(addr->ipv4.sin_addr),
                	 sizeof(struct in_addr), AF_INET);

    if (host == NULL)
    {
     /*
      * No hostname, so return the raw address...
      */

      httpAddrString(addr, name, namelen);
      return (NULL);
    }

    strlcpy(name, host->h_name, namelen);
  }
#endif /* HAVE_GETNAMEINFO */

  return (name);
}


/*
 * 'httpAddrString()' - Convert an address to a numeric string.
 *
 * @since CUPS 1.2@
 */

char *					/* O - Numeric address string */
httpAddrString(const http_addr_t *addr,	/* I - Address to convert */
               char              *s,	/* I - String buffer */
	       int               slen)	/* I - Length of string */
{
  DEBUG_printf(("httpAddrString(addr=%p, s=%p, slen=%d)\n",
                addr, s, slen));

 /*
  * Range check input...
  */

  if (!addr || !s || slen <= 2)
  {
    if (s && slen >= 1)
      *s = '\0';

    return (NULL);
  }

#ifdef AF_LOCAL
  if (addr->addr.sa_family == AF_LOCAL)
    strlcpy(s, addr->un.sun_path, slen);
  else
#endif /* AF_LOCAL */
  if (addr->addr.sa_family == AF_INET)
  {
    unsigned temp;			/* Temporary address */


    temp = ntohl(addr->ipv4.sin_addr.s_addr);

    snprintf(s, slen, "%d.%d.%d.%d", (temp >> 24) & 255,
             (temp >> 16) & 255, (temp >> 8) & 255, temp & 255);
  }
#ifdef AF_INET6
  else if (addr->addr.sa_family == AF_INET6)
  {
#  ifdef HAVE_GETNAMEINFO
    if (getnameinfo(&addr->addr, httpAddrLength(addr), s, slen,
                    NULL, 0, NI_NUMERICHOST))
    {
     /*
      * If we get an error back, then the address type is not supported
      * and we should zero out the buffer...
      */

      s[0] = '\0';

      return (NULL);
    }
#  else
    char	*sptr;			/* Pointer into string */
    int		i;			/* Looping var */
    unsigned	temp;			/* Current value */
    const char	*prefix;		/* Prefix for address */


    prefix = "";
    for (sptr = s, i = 0; i < 4 && addr->ipv6.sin6_addr.s6_addr32[i]; i ++)
    {
      temp = ntohl(addr->ipv6.sin6_addr.s6_addr32[i]);

      snprintf(sptr, slen, "%s%x", prefix, (temp >> 16) & 0xffff);
      prefix = ":";
      slen -= strlen(sptr);
      sptr += strlen(sptr);

      temp &= 0xffff;

      if (temp || i == 3 || addr->ipv6.sin6_addr.s6_addr32[i + 1])
      {
        snprintf(sptr, slen, "%s%x", prefix, temp);
	slen -= strlen(sptr);
	sptr += strlen(sptr);
      }
    }

    if (i < 4)
    {
      while (i < 4 && !addr->ipv6.sin6_addr.s6_addr32[i])
	i ++;

      if (i < 4)
      {
        snprintf(sptr, slen, "%s:", prefix);
	prefix = ":";
	slen -= strlen(sptr);
	sptr += strlen(sptr);

	for (; i < 4; i ++)
	{
          temp = ntohl(addr->ipv6.sin6_addr.s6_addr32[i]);

          if ((temp & 0xffff0000) || addr->ipv6.sin6_addr.s6_addr32[i - 1])
	  {
            snprintf(sptr, slen, "%s%x", prefix, (temp >> 16) & 0xffff);
	    slen -= strlen(sptr);
	    sptr += strlen(sptr);
          }

          snprintf(sptr, slen, "%s%x", prefix, temp & 0xffff);
	  slen -= strlen(sptr);
	  sptr += strlen(sptr);
	}
      }
      else if (sptr == s)
      {
       /*
        * Empty address...
	*/

        strlcpy(s, "::", slen);
	sptr = s + 2;
	slen -= 2;
      }
      else
      {
       /*
	* Empty at end...
	*/

        strlcpy(sptr, "::", slen);
	sptr += 2;
	slen -= 2;
      }
    }
#  endif /* HAVE_GETNAMEINFO */
  }
#endif /* AF_INET6 */
  else
    strlcpy(s, "UNKNOWN", slen);

  DEBUG_printf(("httpAddrString: returning \"%s\"...\n", s));

  return (s);
}


/*
 * 'httpGetHostByName()' - Lookup a hostname or IPv4 address, and return
 *                         address records for the specified name.
 *
 * @deprecated@
 */

struct hostent *			/* O - Host entry */
httpGetHostByName(const char *name)	/* I - Hostname or IP address */
{
  const char		*nameptr;	/* Pointer into name */
  unsigned		ip[4];		/* IP address components */
  _cups_globals_t	*cg = _cupsGlobals();
  					/* Pointer to library globals */


  DEBUG_printf(("httpGetHostByName(name=\"%s\")\n", name));

 /*
  * Avoid lookup delays and configuration problems when connecting
  * to the localhost address...
  */

  if (!strcmp(name, "localhost"))
    name = "127.0.0.1";

 /*
  * This function is needed because some operating systems have a
  * buggy implementation of gethostbyname() that does not support
  * IP addresses.  If the first character of the name string is a
  * number, then sscanf() is used to extract the IP components.
  * We then pack the components into an IPv4 address manually,
  * since the inet_aton() function is deprecated.  We use the
  * htonl() macro to get the right byte order for the address.
  *
  * We also support domain sockets when supported by the underlying
  * OS...
  */

#ifdef AF_LOCAL
  if (name[0] == '/')
  {
   /*
    * A domain socket address, so make an AF_LOCAL entry and return it...
    */

    cg->hostent.h_name      = (char *)name;
    cg->hostent.h_aliases   = NULL;
    cg->hostent.h_addrtype  = AF_LOCAL;
    cg->hostent.h_length    = strlen(name) + 1;
    cg->hostent.h_addr_list = cg->ip_ptrs;
    cg->ip_ptrs[0]          = (char *)name;
    cg->ip_ptrs[1]          = NULL;

    DEBUG_puts("httpGetHostByName: returning domain socket address...");

    return (&cg->hostent);
  }
#endif /* AF_LOCAL */

  for (nameptr = name; isdigit(*nameptr & 255) || *nameptr == '.'; nameptr ++);

  if (!*nameptr)
  {
   /*
    * We have an IPv4 address; break it up and provide the host entry
    * to the caller.
    */

    if (sscanf(name, "%u.%u.%u.%u", ip, ip + 1, ip + 2, ip + 3) != 4)
      return (NULL);			/* Must have 4 numbers */

    if (ip[0] > 255 || ip[1] > 255 || ip[2] > 255 || ip[3] > 255)
      return (NULL);			/* Invalid byte ranges! */

    cg->ip_addr = htonl(((((((ip[0] << 8) | ip[1]) << 8) | ip[2]) << 8) |
                         ip[3]));

   /*
    * Fill in the host entry and return it...
    */

    cg->hostent.h_name      = (char *)name;
    cg->hostent.h_aliases   = NULL;
    cg->hostent.h_addrtype  = AF_INET;
    cg->hostent.h_length    = 4;
    cg->hostent.h_addr_list = cg->ip_ptrs;
    cg->ip_ptrs[0]          = (char *)&(cg->ip_addr);
    cg->ip_ptrs[1]          = NULL;

    DEBUG_puts("httpGetHostByName: returning IPv4 address...");

    return (&cg->hostent);
  }
  else
  {
   /*
    * Use the gethostbyname() function to get the IPv4 address for
    * the name...
    */

    DEBUG_puts("httpGetHostByName: returning domain lookup address(es)...");

    return (gethostbyname(name));
  }
}


/*
 * 'httpGetHostname()' - Get the FQDN for the connection or local system.
 *
 * When "http" points to a connected socket, return the hostname or
 * address that was used in the call to httpConnect() or httpConnectEncrypt().
 * Otherwise, return the FQDN for the local system using both gethostname()
 * and gethostbyname() to get the local hostname with domain.
 *
 * @since CUPS 1.2@
 */

const char *				/* O - FQDN for connection or system */
httpGetHostname(http_t *http,		/* I - HTTP connection or NULL */
                char   *s,		/* I - String buffer for name */
                int    slen)		/* I - Size of buffer */
{
  struct hostent	*host;		/* Host entry to get FQDN */


  if (!s || slen <= 1)
    return (NULL);

  if (http)
  {
    if (http->hostname[0] == '/')
      strlcpy(s, "localhost", slen);
    else
      strlcpy(s, http->hostname, slen);
  }
  else
  {
   /*
    * Get the hostname...
    */

    if (gethostname(s, slen) < 0)
      strlcpy(s, "localhost", slen);

    if (!strchr(s, '.'))
    {
     /*
      * The hostname is not a FQDN, so look it up...
      */

      if ((host = gethostbyname(s)) != NULL && host->h_name)
	strlcpy(s, host->h_name, slen);
    }
  }

 /*
  * Return the hostname with as much domain info as we have...
  */

  return (s);
}


/*
 * End of "$Id: http-addr.c 6814 2007-08-20 20:09:25Z mike $".
 */