/****************************************************************************
* apps/system/netdb/netdb.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#ifdef CONFIG_SYSTEM_NETDB
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_SYSTEM_NETDB_STACKSIZE
# define CONFIG_SYSTEM_NETDB_STACKSIZE 2048
#endif
#ifndef CONFIG_SYSTEM_NETDB_PRIORITY
# define CONFIG_SYSTEM_NETDB_PRIORITY 50
#endif
/* REVIST: Currently the availability of gethostbyaddr() depends on
* CONFIG_NETDB_HOSTFILE. That might not always be true, however.
*/
#undef HAVE_GETHOSTBYADDR
#ifdef CONFIG_NETDB_HOSTFILE
# define HAVE_GETHOSTBYADDR 1
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
static void show_usage(FAR const char *progname, int exitcode) noreturn_function;
static void show_usage(FAR const char *progname, int exitcode)
{
fprintf(stderr, "USAGE: %s --ipv4 <ipv4-addr>\n", progname);
#ifdef HAVE_GETHOSTBYADDR
fprintf(stderr, " %s --ipv6 <ipv6-addr>\n", progname);
fprintf(stderr, " %s --host <host-name>\n", progname);
#endif
fprintf(stderr, " %s --help\n", progname);
exit(exitcode);
}
/****************************************************************************
* Public Functions
****************************************************************************/
int netdb_main(int argc, char **argv)
{
FAR struct hostent *host;
FAR const char *addrtype;
char buffer[48];
int ret;
/* Handle: netdb --help */
if (argc == 2 && strcmp(argv[1], "--help") == 0)
{
show_usage(argv[0], EXIT_SUCCESS);
}
/* Otherwise there must be exactly two arguments following the program name */
else if (argc < 3)
{
fprintf(stderr, "ERROR -- Missing arguments\n\n");
show_usage(argv[0], EXIT_FAILURE);
}
else if (argc > 3)
{
fprintf(stderr, "ERROR -- Too many arguments\n\n");
show_usage(argv[0], EXIT_FAILURE);
}
#ifdef HAVE_GETHOSTBYADDR
/* Handle: netdb --ipv4 <ipv4-addr> */
else if (strcmp(argv[1], "--ipv4") == 0)
{
struct in_addr addr;
/* Convert the address to binary */
ret = inet_pton(AF_INET, argv[2], &addr);
if (ret < 0)
{
fprintf(stderr, "ERROR -- Bad IPv4 address\n\n");
show_usage(argv[0], EXIT_FAILURE);
}
/* Get the matching host name + any aliases */
host = gethostbyaddr(&addr, sizeof(struct in_addr), AF_INET);
if (!host)
{
fprintf(stderr, "ERROR -- gethostbyaddr failed. h_errno=%d\n\n",
h_errno);
return EXIT_FAILURE;
}
}
/* Handle: netdb --ipv46<ipv6-addr> */
else if (strcmp(argv[1], "--ipv6") == 0)
{
struct in_addr addr;
/* Convert the address to binary */
ret = inet_pton(AF_INET6, argv[2], &addr);
if (ret < 0)
{
fprintf(stderr, "ERROR -- Bad IPv6 address\n\n");
show_usage(argv[0], EXIT_FAILURE);
}
/* Get the matching host name + any aliases */
host = gethostbyaddr(&addr, sizeof(struct in6_addr), AF_INET6);
if (!host)
{
fprintf(stderr, "ERROR -- gethostbyaddr failed. h_errno=%d\n\n",
h_errno);
return EXIT_FAILURE;
}
}
#endif /* HAVE_GETHOSTBYADDR */
/* Handle: netdb --host <host-name> */
else if (strcmp(argv[1], "--host") == 0)
{
/* Get the matching address + any aliases */
host = gethostbyname(argv[2]);
if (!host)
{
fprintf(stderr, "ERROR -- gethostbyname failed. h_errno=%d\n\n",
h_errno);
return EXIT_FAILURE;
}
}
/* The first argument is not any argument that we recognize */
else
{
fprintf(stderr, "ERROR -- Unrecognized option: %s\n\n", argv[1]);
show_usage(argv[0], EXIT_FAILURE);
}
/* If we get here, then gethostbyname() or gethostbyaddr() was
* successfully.
*/
/* Convert the address to a string */
/* Handle IPv4 addresses */
if (host->h_addrtype == AF_INET)
{
if (inet_ntop(AF_INET, host->h_addr, buffer, 48) == NULL)
{
fprintf(stderr,
"ERROR -- gethostbyname failed. h_errno=%d\n\n",
h_errno);
return EXIT_FAILURE;
}
addrtype = "IPv4";
}
/* Handle IPv6 addresses */
else if (host->h_addrtype == AF_INET6)
{
if (inet_ntop(AF_INET6, host->h_addr, buffer, 48) == NULL)
{
fprintf(stderr,
"ERROR -- gethostbyname failed. h_errno=%d\n\n",
h_errno);
return EXIT_FAILURE;
}
addrtype = "IPv6";
}
/* Huh? */
else
{
fprintf(stderr, "ERROR -- gethostbyname address type %d not recognized.\n\n",
host->h_addrtype);
return EXIT_FAILURE;
}
/* Print the host name / address mapping */
printf("Host: %s %s Addr: %s\n", host->h_name, addrtype, buffer);
/* Print any host name aliases */
if (host->h_aliases != NULL && *host->h_aliases != NULL)
{
FAR char **alias;
printf("Aliases:");
for (alias = host->h_aliases; *alias != NULL; alias++)
{
printf(" %s", *alias);
}
putchar('\n');
}
return EXIT_SUCCESS;
}
#endif /* CONFIG_SYSTEM_NETDB */