summaryrefslogtreecommitdiffstats
path: root/nameserv.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--nameserv.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/nameserv.c b/nameserv.c
new file mode 100644
index 0000000..9f7e648
--- /dev/null
+++ b/nameserv.c
@@ -0,0 +1,166 @@
+/*
+ chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Richard P. Curnow 1997-2003
+ * Copyright (C) Miroslav Lichvar 2009-2011
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ **********************************************************************
+
+ =======================================================================
+
+ Functions to do name to IP address conversion
+
+ */
+
+#include "config.h"
+
+#include "sysincl.h"
+
+#include <netdb.h>
+#include <resolv.h>
+
+#include "nameserv.h"
+#include "socket.h"
+#include "util.h"
+
+/* ================================================== */
+
+static int address_family = IPADDR_UNSPEC;
+
+void
+DNS_SetAddressFamily(int family)
+{
+ address_family = family;
+}
+
+DNS_Status
+DNS_Name2IPAddress(const char *name, IPAddr *ip_addrs, int max_addrs)
+{
+ struct addrinfo hints, *res, *ai;
+ int i, result;
+ IPAddr ip;
+
+ max_addrs = MIN(max_addrs, DNS_MAX_ADDRESSES);
+
+ for (i = 0; i < max_addrs; i++)
+ ip_addrs[i].family = IPADDR_UNSPEC;
+
+ /* Avoid calling getaddrinfo() if the name is an IP address */
+ if (UTI_StringToIP(name, &ip)) {
+ if (address_family != IPADDR_UNSPEC && ip.family != address_family)
+ return DNS_Failure;
+ if (max_addrs >= 1)
+ ip_addrs[0] = ip;
+ return DNS_Success;
+ }
+
+ memset(&hints, 0, sizeof (hints));
+
+ switch (address_family) {
+ case IPADDR_INET4:
+ hints.ai_family = AF_INET;
+ break;
+#ifdef FEAT_IPV6
+ case IPADDR_INET6:
+ hints.ai_family = AF_INET6;
+ break;
+#endif
+ default:
+ hints.ai_family = AF_UNSPEC;
+ }
+ hints.ai_socktype = SOCK_DGRAM;
+
+ result = getaddrinfo(name, NULL, &hints, &res);
+
+ if (result) {
+#ifdef FORCE_DNSRETRY
+ return DNS_TryAgain;
+#else
+ return result == EAI_AGAIN ? DNS_TryAgain : DNS_Failure;
+#endif
+ }
+
+ for (ai = res, i = 0; i < max_addrs && ai != NULL; ai = ai->ai_next) {
+ switch (ai->ai_family) {
+ case AF_INET:
+ if (address_family != IPADDR_UNSPEC && address_family != IPADDR_INET4)
+ continue;
+ ip_addrs[i].family = IPADDR_INET4;
+ ip_addrs[i].addr.in4 = ntohl(((struct sockaddr_in *)ai->ai_addr)->sin_addr.s_addr);
+ i++;
+ break;
+#ifdef FEAT_IPV6
+ case AF_INET6:
+ if (address_family != IPADDR_UNSPEC && address_family != IPADDR_INET6)
+ continue;
+ /* Don't return an address that would lose a scope ID */
+ if (((struct sockaddr_in6 *)ai->ai_addr)->sin6_scope_id != 0)
+ continue;
+ ip_addrs[i].family = IPADDR_INET6;
+ memcpy(&ip_addrs[i].addr.in6, &((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr.s6_addr,
+ sizeof (ip_addrs->addr.in6));
+ i++;
+ break;
+#endif
+ }
+ }
+
+ freeaddrinfo(res);
+
+ return !max_addrs || ip_addrs[0].family != IPADDR_UNSPEC ? DNS_Success : DNS_Failure;
+}
+
+/* ================================================== */
+
+int
+DNS_IPAddress2Name(IPAddr *ip_addr, char *name, int len)
+{
+ char *result = NULL;
+#ifdef FEAT_IPV6
+ struct sockaddr_in6 saddr;
+#else
+ struct sockaddr_in saddr;
+#endif
+ IPSockAddr ip_saddr;
+ socklen_t slen;
+ char hbuf[NI_MAXHOST];
+
+ ip_saddr.ip_addr = *ip_addr;
+ ip_saddr.port = 0;
+
+ slen = SCK_IPSockAddrToSockaddr(&ip_saddr, (struct sockaddr *)&saddr, sizeof (saddr));
+ if (!getnameinfo((struct sockaddr *)&saddr, slen, hbuf, sizeof (hbuf), NULL, 0, 0))
+ result = hbuf;
+
+ if (result == NULL)
+ result = UTI_IPToString(ip_addr);
+ if (snprintf(name, len, "%s", result) >= len)
+ return 0;
+
+ return 1;
+}
+
+/* ================================================== */
+
+void
+DNS_Reload(void)
+{
+ res_init();
+}
+
+/* ================================================== */
+