path: root/contrib/libs/c-ares/src/lib/ares_options.c

/* MIT License
 *
 * Copyright (c) 1998 Massachusetts Institute of Technology
 * Copyright (c) 2008 Daniel Stenberg
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 * SPDX-License-Identifier: MIT
 */

#include "ares_setup.h"

#ifdef HAVE_ARPA_INET_H
#  include <arpa/inet.h>
#endif

#include "ares.h"
#include "ares_data.h"
#include "ares_inet_net_pton.h"
#include "ares_private.h"


int ares_get_servers(ares_channel channel,
                     struct ares_addr_node **servers)
{
  struct ares_addr_node *srvr_head = NULL;
  struct ares_addr_node *srvr_last = NULL;
  struct ares_addr_node *srvr_curr;
  int status = ARES_SUCCESS;
  int i;

  if (!channel)
    return ARES_ENODATA;

  for (i = 0; i < channel->nservers; i++)
    {
      /* Allocate storage for this server node appending it to the list */
      srvr_curr = ares_malloc_data(ARES_DATATYPE_ADDR_NODE);
      if (!srvr_curr)
        {
          status = ARES_ENOMEM;
          break;
        }
      if (srvr_last)
        {
          srvr_last->next = srvr_curr;
        }
      else
        {
          srvr_head = srvr_curr;
        }
      srvr_last = srvr_curr;

      /* Fill this server node data */
      srvr_curr->family = channel->servers[i].addr.family;
      if (srvr_curr->family == AF_INET)
        memcpy(&srvr_curr->addrV4, &channel->servers[i].addr.addrV4,
               sizeof(srvr_curr->addrV4));
      else
        memcpy(&srvr_curr->addrV6, &channel->servers[i].addr.addrV6,
               sizeof(srvr_curr->addrV6));
    }

  if (status != ARES_SUCCESS)
    {
      if (srvr_head)
        {
          ares_free_data(srvr_head);
          srvr_head = NULL;
        }
    }

  *servers = srvr_head;

  return status;
}

int ares_get_servers_ports(ares_channel channel,
                           struct ares_addr_port_node **servers)
{
  struct ares_addr_port_node *srvr_head = NULL;
  struct ares_addr_port_node *srvr_last = NULL;
  struct ares_addr_port_node *srvr_curr;
  int status = ARES_SUCCESS;
  int i;

  if (!channel)
    return ARES_ENODATA;

  for (i = 0; i < channel->nservers; i++)
    {
      /* Allocate storage for this server node appending it to the list */
      srvr_curr = ares_malloc_data(ARES_DATATYPE_ADDR_PORT_NODE);
      if (!srvr_curr)
        {
          status = ARES_ENOMEM;
          break;
        }
      if (srvr_last)
        {
          srvr_last->next = srvr_curr;
        }
      else
        {
          srvr_head = srvr_curr;
        }
      srvr_last = srvr_curr;

      /* Fill this server node data */
      srvr_curr->family = channel->servers[i].addr.family;
      srvr_curr->udp_port = ntohs((unsigned short)channel->servers[i].addr.udp_port);
      srvr_curr->tcp_port = ntohs((unsigned short)channel->servers[i].addr.tcp_port);
      if (srvr_curr->family == AF_INET)
        memcpy(&srvr_curr->addrV4, &channel->servers[i].addr.addrV4,
               sizeof(srvr_curr->addrV4));
      else
        memcpy(&srvr_curr->addrV6, &channel->servers[i].addr.addrV6,
               sizeof(srvr_curr->addrV6));
    }

  if (status != ARES_SUCCESS)
    {
      if (srvr_head)
        {
          ares_free_data(srvr_head);
          srvr_head = NULL;
        }
    }

  *servers = srvr_head;

  return status;
}

int ares_set_servers(ares_channel channel,
                     struct ares_addr_node *servers)
{
  struct ares_addr_node *srvr;
  int num_srvrs = 0;
  int i;

  if (ares_library_initialized() != ARES_SUCCESS)
    return ARES_ENOTINITIALIZED;  /* LCOV_EXCL_LINE: n/a on non-WinSock */

  if (!channel)
    return ARES_ENODATA;

  if (ares__llist_len(channel->all_queries) != 0)
    return ARES_ENOTIMP;

  ares__destroy_servers_state(channel);

  for (srvr = servers; srvr; srvr = srvr->next)
    {
      num_srvrs++;
    }

  if (num_srvrs > 0)
    {
      /* Allocate storage for servers state */
      channel->servers = ares_malloc(num_srvrs * sizeof(*channel->servers));
      if (!channel->servers)
        {
          return ARES_ENOMEM;
        }
      memset(channel->servers, 0, num_srvrs * sizeof(*channel->servers));
      channel->nservers = num_srvrs;
      /* Fill servers state address data */
      for (i = 0, srvr = servers; srvr; i++, srvr = srvr->next)
        {
          channel->servers[i].addr.family = srvr->family;
          channel->servers[i].addr.udp_port = 0;
          channel->servers[i].addr.tcp_port = 0;
          if (srvr->family == AF_INET)
            memcpy(&channel->servers[i].addr.addrV4, &srvr->addrV4,
                   sizeof(srvr->addrV4));
          else
            memcpy(&channel->servers[i].addr.addrV6, &srvr->addrV6,
                   sizeof(srvr->addrV6));
        }
      /* Initialize servers state remaining data */
      ares__init_servers_state(channel);
    }

  return ARES_SUCCESS;
}

int ares_set_servers_ports(ares_channel channel,
                           struct ares_addr_port_node *servers)
{
  struct ares_addr_port_node *srvr;
  int num_srvrs = 0;
  int i;

  if (ares_library_initialized() != ARES_SUCCESS)
    return ARES_ENOTINITIALIZED;  /* LCOV_EXCL_LINE: n/a on non-WinSock */

  if (!channel)
    return ARES_ENODATA;

  if (ares__llist_len(channel->all_queries) != 0)
    return ARES_ENOTIMP;

  ares__destroy_servers_state(channel);

  for (srvr = servers; srvr; srvr = srvr->next)
    {
      num_srvrs++;
    }

  if (num_srvrs > 0)
    {
      /* Allocate storage for servers state */
      channel->servers = ares_malloc(num_srvrs * sizeof(*channel->servers));
      if (!channel->servers)
        {
          return ARES_ENOMEM;
        }
      memset(channel->servers, 0, num_srvrs * sizeof(*channel->servers));
      channel->nservers = num_srvrs;
      /* Fill servers state address data */
      for (i = 0, srvr = servers; srvr; i++, srvr = srvr->next)
        {
          channel->servers[i].addr.family = srvr->family;
          channel->servers[i].addr.udp_port = htons((unsigned short)srvr->udp_port);
          channel->servers[i].addr.tcp_port = htons((unsigned short)srvr->tcp_port);
          if (srvr->family == AF_INET)
            memcpy(&channel->servers[i].addr.addrV4, &srvr->addrV4,
                   sizeof(srvr->addrV4));
          else
            memcpy(&channel->servers[i].addr.addrV6, &srvr->addrV6,
                   sizeof(srvr->addrV6));
        }
      /* Initialize servers state remaining data */
      ares__init_servers_state(channel);
    }

  return ARES_SUCCESS;
}

/* Incomming string format: host[:port][,host[:port]]... */
/* IPv6 addresses with ports require square brackets [fe80::1%lo0]:53 */
static int set_servers_csv(ares_channel channel,
                           const char* _csv, int use_port)
{
  size_t i;
  char* csv = NULL;
  char* ptr;
  char* start_host;
  int cc = 0;
  int rv = ARES_SUCCESS;
  struct ares_addr_port_node *servers = NULL;
  struct ares_addr_port_node *last = NULL;

  if (ares_library_initialized() != ARES_SUCCESS)
    return ARES_ENOTINITIALIZED;  /* LCOV_EXCL_LINE: n/a on non-WinSock */

  if (!channel)
    return ARES_ENODATA;

  i = strlen(_csv);
  if (i == 0)
     return ARES_SUCCESS; /* blank all servers */

  csv = ares_malloc(i + 2);
  if (!csv)
    return ARES_ENOMEM;

  strcpy(csv, _csv);
  if (csv[i-1] != ',') { /* make parsing easier by ensuring ending ',' */
    csv[i] = ',';
    csv[i+1] = 0;
  }

  start_host = csv;
  for (ptr = csv; *ptr; ptr++) {
    if (*ptr == ':') {
      /* count colons to determine if we have an IPv6 number or IPv4 with
         port */
      cc++;
    }
    else if (*ptr == '[') {
      /* move start_host if an open square bracket is found wrapping an IPv6
         address */
      start_host = ptr + 1;
    }
    else if (*ptr == ',') {
      char* pp = ptr - 1;
      char* p = ptr;
      int port = 0;
      struct in_addr in4;
      struct ares_in6_addr in6;
      struct ares_addr_port_node *s = NULL;

      *ptr = 0; /* null terminate host:port string */
      /* Got an entry..see if the port was specified. */
      if (cc > 0) {
        while (pp > start_host) {
          /* a single close square bracket followed by a colon, ']:' indicates
             an IPv6 address with port */
          if ((*pp == ']') && (*p == ':'))
            break; /* found port */
          /* a single colon, ':' indicates an IPv4 address with port */
          if ((*pp == ':') && (cc == 1))
            break; /* found port */
          if (!(ISDIGIT(*pp) || (*pp == ':'))) {
            /* Found end of digits before we found :, so wasn't a port */
            /* must allow ':' for IPv6 case of ']:' indicates we found a port */
            pp = p = ptr;
            break;
          }
          pp--;
          p--;
        }
        if ((pp != start_host) && ((pp + 1) < ptr)) {
          /* Found it. Parse over the port number */
          /* when an IPv6 address is wrapped with square brackets the port
             starts at pp + 2 */
          if (*pp == ']')
            p++; /* move p before ':' */
          /* p will point to the start of the port */
          port = (int)strtol(p, NULL, 10);
          *pp = 0; /* null terminate host */
        }
      }
      /* resolve host, try ipv4 first, rslt is in network byte order */
      rv = ares_inet_pton(AF_INET, start_host, &in4);
      if (!rv) {
        /* Ok, try IPv6 then */
        rv = ares_inet_pton(AF_INET6, start_host, &in6);
        if (!rv) {
          rv = ARES_EBADSTR;
          goto out;
        }
        /* was ipv6, add new server */
        s = ares_malloc(sizeof(*s));
        if (!s) {
          rv = ARES_ENOMEM;
          goto out;
        }
        s->family = AF_INET6;
        memcpy(&s->addr, &in6, sizeof(struct ares_in6_addr));
      }
      else {
        /* was ipv4, add new server */
        s = ares_malloc(sizeof(*s));
        if (!s) {
          rv = ARES_ENOMEM;
          goto out;
        }
        s->family = AF_INET;
        memcpy(&s->addr, &in4, sizeof(struct in_addr));
      }
      if (s) {
        s->udp_port = use_port ? port: 0;
        s->tcp_port = s->udp_port;
        s->next = NULL;
        if (last) {
          last->next = s;
          /* need to move last to maintain the linked list */
          last = last->next;
        }
        else {
          servers = s;
          last = s;
        }
      }

      /* Set up for next one */
      start_host = ptr + 1;
      cc = 0;
    }
  }

  rv = ares_set_servers_ports(channel, servers);

  out:
  if (csv)
    ares_free(csv);
  while (servers) {
    struct ares_addr_port_node *s = servers;
    servers = servers->next;
    ares_free(s);
  }

  return rv;
}

int ares_set_servers_csv(ares_channel channel,
                         const char* _csv)
{
  return set_servers_csv(channel, _csv, FALSE);
}

int ares_set_servers_ports_csv(ares_channel channel,
                               const char* _csv)
{
  return set_servers_csv(channel, _csv, TRUE);
}