incubator-nuttx/libc/netdb/lib_dnsaddserver.c

275 lines
7.3 KiB
C

/****************************************************************************
* libc/netdb/lib_dnsaddserver.c
*
* Copyright (C) 2016 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 <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/dns.h>
#include "netdb/lib_dns.h"
#ifdef CONFIG_NETDB_DNSCLIENT
/****************************************************************************
* Public Data
****************************************************************************/
#ifndef CONFIG_NETDB_RESOLVCONF
/* The DNS server address */
union dns_server_u g_dns_server;
bool g_dns_address; /* true: We have the address of the DNS server */
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: dns_add_nameserver
*
* Description:
* Configure which DNS server to use for queries
*
****************************************************************************/
#ifdef CONFIG_NETDB_RESOLVCONF
int dns_add_nameserver(FAR const struct sockaddr *addr, socklen_t addrlen)
{
FAR FILE *stream;
char addrstr[DNS_MAX_ADDRSTR];
#ifdef CONFIG_NETDB_RESOLVCONF_NONSTDPORT
uint16_t port;
#endif
int status;
int ret;
stream = fopen(CONFIG_NETDB_RESOLVCONF_PATH, "at");
if (stream == NULL)
{
int errcode = errno;
ndbg("ERROR: Failed to open %s: %d\n",
CONFIG_NETDB_RESOLVCONF_PATH, errcode);
DEBUGASSERT(errcode > 0);
return -errcode;
}
#ifdef CONFIG_NET_IPv4
/* Check for an IPv4 address */
if (addr->sa_family == AF_INET)
{
if (addrlen < sizeof(struct sockaddr_in))
{
ret = -EINVAL;
goto errout;
}
else
{
FAR struct sockaddr_in *in4 = (FAR struct sockaddr_in *)addr;
if (inet_ntop(AF_INET, &in4->sin_addr, addrstr, DNS_MAX_ADDRSTR) == NULL)
{
ret = -errno;
ndbg("ERROR: inet_ntop failed: %d\n", errcode);
DEBUGASSERT(errcode < 0);
goto errout;
}
#ifdef CONFIG_NETDB_RESOLVCONF_NONSTDPORT
/* Get the port number */
port = ntohs(in4->sin_port);
#endif
}
}
else
#endif
#ifdef CONFIG_NET_IPv6
/* Check for an IPv6 address */
if (addr->sa_family == AF_INET6)
{
if (addrlen < sizeof(struct sockaddr_in6))
{
ret = -EINVAL;
goto errout;
}
else
{
FAR struct sockaddr_in6 *in6 = (FAR struct sockaddr_in6 *)addr;
if (inet_ntop(AF_INET6, &in6->sin6_addr, addrstr, DNS_MAX_ADDRSTR) == NULL)
{
ret = -errno;
ndbg("ERROR: inet_ntop failed: %d\n", errcode);
DEBUGASSERT(errcode < 0);
goto errout;
}
#ifdef CONFIG_NETDB_RESOLVCONF_NONSTDPORT
/* Get the port number */
port = ntohs(in6->sin6_port);
#endif
}
}
else
#endif
{
nvdbg("ERROR: Unsupported family: %d\n",
g_dns_server.addr.sa_family);
ret = -ENOSYS;
goto errout;
}
/* Write the new record to the end of the resolv.conf file. */
#ifdef CONFIG_NETDB_RESOLVCONF_NONSTDPORT
/* The OpenBSD version supports a [host]:port syntax. When a non-standard
* port is specified the host address must be enclosed in square brackets.
* For example:
*
* nameserver [10.0.0.1]:5353
* nameserver [::1]:5353
*/
if (port != 0 && port != DNS_DEFAULT_PORT)
{
status = fprintf(stream, "%s [%s]:%u\n",
NETDB_DNS_KEYWORD, addrstr, port);
}
else
#endif
{
status = fprintf(stream, "%s %s\n",
NETDB_DNS_KEYWORD, addrstr);
}
if (status < 0)
{
ret = -errno;
ndbg("ERROR: fprintf failed: %d\n", errcode);
DEBUGASSERT(errcode < 0);
goto errout;
}
ret = OK;
errout:
fclose(stream);
return ret;
}
#else /* CONFIG_NETDB_RESOLVCONF */
int dns_add_nameserver(FAR const struct sockaddr *addr, socklen_t addrlen)
{
FAR uint16_t *pport;
size_t copylen;
DEBUGASSERT(addr != NULL);
/* Copy the new server IP address into our private global data structure */
#ifdef CONFIG_NET_IPv4
/* Check for an IPv4 address */
if (addr->sa_family == AF_INET)
{
/* Set up for the IPv4 address copy */
copylen = sizeof(struct sockaddr_in);
pport = &g_dns_server.ipv4.sin_port;
}
else
#endif
#ifdef CONFIG_NET_IPv6
/* Check for an IPv6 address */
if (addr->sa_family == AF_INET6)
{
/* Set up for the IPv6 address copy */
copylen = sizeof(struct sockaddr_in6);
pport = &g_dns_server.ipv6.sin6_port;
}
else
#endif
{
nvdbg("ERROR: Unsupported family: %d\n", addr->sa_family);
return -ENOSYS;
}
/* Copy the IP address */
if (addrlen < copylen)
{
nvdbg("ERROR: Invalid addrlen %ld for family %d\n",
(long)addrlen, addr->sa_family);
return -EINVAL;
}
memcpy(&g_dns_server.addr, addr, copylen);
/* A port number of zero means to use the default DNS server port number */
if (*pport == 0)
{
*pport = HTONS(DNS_DEFAULT_PORT);
}
/* We now have a valid DNS address */
g_dns_address = true;
return OK;
}
#endif /* CONFIG_NETDB_RESOLVCONF */
#endif /* CONFIG_NETDB_DNSCLIENT */