C++ (Cpp) dns_set_srch_internal Examples

Example #1

File: udns_init.c Project: Icarus-xx/reconnoiter

static int dns_init_resolvconf(struct dns_ctx *ctx) {
  char *v;
  char buf[2049];	/* this buffer is used to hold /etc/resolv.conf */
  int has_srch = 0;

  /* read resolv.conf... */
  { int fd = open("/etc/resolv.conf", O_RDONLY);
    if (fd >= 0) {
      int l = read(fd, buf, sizeof(buf) - 1);
      close(fd);
      buf[l < 0 ? 0 : l] = '\0';
    }
    else
      buf[0] = '\0';
  }
  if (buf[0]) {	/* ...and parse it */
    char *line, *nextline;
    line = buf;
    do {
      nextline = strchr(line, '\n');
      if (nextline) *nextline++ = '\0';
      v = line;
      while(*v && !ISSPACE(*v)) ++v;
      if (!*v) continue;
      *v++ = '\0';
      while(ISSPACE(*v)) ++v;
      if (!*v) continue;
      if (strcmp(line, "domain") == 0) {
        dns_set_srch_internal(ctx, strtok(v, space));
	has_srch = 1;
      }
      else if (strcmp(line, "search") == 0) {
        dns_set_srch_internal(ctx, v);
	has_srch = 1;
      }
      else if (strcmp(line, "nameserver") == 0)
        dns_add_serv(ctx, strtok(v, space));
      else if (strcmp(line, "options") == 0)
        dns_set_opts(ctx, v);
    } while((line = nextline) != NULL);
  }

  buf[sizeof(buf)-1] = '\0';

  /* get list of nameservers from env. vars. */
  if ((v = getenv("NSCACHEIP")) != NULL ||
      (v = getenv("NAMESERVERS")) != NULL) {
    strncpy(buf, v, sizeof(buf) - 1);
    dns_set_serv_internal(ctx, buf);
  }
  /* if $LOCALDOMAIN is set, use it for search list */
  if ((v = getenv("LOCALDOMAIN")) != NULL) {
    strncpy(buf, v, sizeof(buf) - 1);
    dns_set_srch_internal(ctx, buf);
    has_srch = 1;
  }
  if ((v = getenv("RES_OPTIONS")) != NULL)
    dns_set_opts(ctx, v);

  /* if still no search list, use local domain name */
  if (has_srch &&
      gethostname(buf, sizeof(buf) - 1) == 0 &&
      (v = strchr(buf, '.')) != NULL &&
      *++v != '\0')
    dns_add_srch(ctx, v);

  return 0;
}

Example #2

static int dns_init_resolvconf(struct dns_ctx *ctx) {
  char *v;
  char buf[4097];	/* this buffer is used to hold /etc/resolv.conf */
  int has_srch = 0;

  /* read resolv.conf... */
  { int fd = open("/etc/resolv.conf", O_RDONLY);
    if (fd >= 0) {
      int l = read(fd, buf, sizeof(buf) - 1);
      close(fd);
      buf[l < 0 ? 0 : l] = '\0';
    }
    else
      buf[0] = '\0';
  }
  if (buf[0]) {	/* ...and parse it */
    char *line, *nextline;
    line = buf;
    do {
      nextline = strchr(line, '\n');
      if (nextline) *nextline++ = '\0';
      v = line;
      while(*v && !ISSPACE(*v)) ++v;
      if (!*v) continue;
      *v++ = '\0';
      while(ISSPACE(*v)) ++v;
      if (!*v) continue;
      if (strcmp(line, "domain") == 0) {
        dns_set_srch_internal(ctx, strtok(v, space));
	has_srch = 1;
      }
      else if (strcmp(line, "search") == 0) {
        dns_set_srch_internal(ctx, v);
	has_srch = 1;
      }
      else if (strcmp(line, "nameserver") == 0)
        dns_add_serv(ctx, strtok(v, space));
      else if (strcmp(line, "options") == 0)
        dns_set_opts(ctx, v);
    } while((line = nextline) != NULL);
  }

  buf[sizeof(buf)-1] = '\0';

#if TARGET_OS_IPHONE
  // SOLUTION FOUND:
  // http://iphone.galloway.me.uk/2009/11/iphone-dns-servers/
  
  // ORIGINAL CODE EXAMPLE:
  //
  //      #if TARGET_OS_IPHONE
  //      #include <resolv.h>
  //      #endif
  // 
  //      ...
  // 
  //      #if TARGET_OS_IPHONE
  //      // XXX: On the iPhone we need to get the DNS servers using resolv.h magic
  //      if ((_res.options & RES_INIT) == 0) res_init();
  //      channel->nservers = _res.nscount;
  //      channel->servers = malloc(channel->nservers * sizeof(struct server_state));
  //      memset(channel->servers, '\0', channel->nservers * sizeof(struct server_state));
  // 
  //      int i;
  //      for (i = 0; i < channel->nservers; i++)
  //      {
  //          memcpy(&channel->servers[i].addr, &_res.nsaddr_list[i].sin_addr, sizeof(struct in_addr));
  //      }
  //      #endif

  if ((_res.options & RES_INIT) == 0) res_init();
  
  int i;
  for (i = 0; i < _res.nscount; i++)
  {
    struct sockaddr_in address;
    memset(&address, 0, sizeof(address));
    address.sin_family = AF_INET;
    address.sin_addr = _res.nsaddr_list[i].sin_addr;              // loopback is a special case since it could be stored as ::1 in IPv6

    dns_add_serv_s(ctx, (struct sockaddr *)&address);
  }
#endif //TARGET_OS_IPHONE

  /* get list of nameservers from env. vars. */
  if ((v = getenv("NSCACHEIP")) != NULL ||
      (v = getenv("NAMESERVERS")) != NULL) {
    strncpy(buf, v, sizeof(buf) - 1);
    dns_set_serv_internal(ctx, buf);
  }
  /* if $LOCALDOMAIN is set, use it for search list */
  if ((v = getenv("LOCALDOMAIN")) != NULL) {
    strncpy(buf, v, sizeof(buf) - 1);
    dns_set_srch_internal(ctx, buf);
    has_srch = 1;
  }
  if ((v = getenv("RES_OPTIONS")) != NULL)
    dns_set_opts(ctx, v);

  /* if still no search list, use local domain name */
  if (has_srch &&
      gethostname(buf, sizeof(buf) - 1) == 0 &&
      (v = strchr(buf, '.')) != NULL &&
      *++v != '\0')
    dns_add_srch(ctx, v);

  return 0;
}