*/
#include <resolv.h>
-#include "busybox.h"
+#include "libbb.h"
/*
* I'm only implementing non-interactive mode;
* ns3.kernel.org internet address = 204.152.191.36
*/
-static int sockaddr_to_dotted(struct sockaddr *saddr, char *buf, int buflen)
-{
- if (buflen <= 0) return -1;
- buf[0] = '\0';
- if (saddr->sa_family == AF_INET) {
- inet_ntop(AF_INET, &((struct sockaddr_in*)saddr)->sin_addr, buf, buflen);
- return 0;
- }
- if (saddr->sa_family == AF_INET6) {
- inet_ntop(AF_INET6, &((struct sockaddr_in6*)saddr)->sin6_addr, buf, buflen);
- return 0;
- }
- return -1;
-}
-
static int print_host(const char *hostname, const char *header)
{
- char str[128]; /* IPv6 address will fit, hostnames hopefully too */
+ /* We can't use xhost2sockaddr() - we want to get ALL addresses,
+ * not just one */
+
struct addrinfo *result = NULL;
int rc;
struct addrinfo hint;
hint.ai_socktype = SOCK_STREAM;
// hint.ai_flags = AI_CANONNAME;
rc = getaddrinfo(hostname, NULL /*service*/, &hint, &result);
+
if (!rc) {
struct addrinfo *cur = result;
- // printf("%s\n", cur->ai_canonname); ?
+ unsigned cnt = 0;
+
+ printf("%-10s %s\n", header, hostname);
+ // puts(cur->ai_canonname); ?
while (cur) {
- sockaddr_to_dotted(cur->ai_addr, str, sizeof(str));
- printf("%s %s\nAddress: %s", header, hostname, str);
- str[0] = ' ';
- if (getnameinfo(cur->ai_addr, cur->ai_addrlen, str+1, sizeof(str)-1, NULL, 0, NI_NAMEREQD))
- str[0] = '\0';
- puts(str);
+ char *dotted, *revhost;
+ dotted = xmalloc_sockaddr2dotted_noport(cur->ai_addr);
+ revhost = xmalloc_sockaddr2hostonly_noport(cur->ai_addr);
+
+ printf("Address %u: %s%c", ++cnt, dotted, revhost ? ' ' : '\n');
+ if (revhost) {
+ puts(revhost);
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(revhost);
+ }
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(dotted);
cur = cur->ai_next;
}
} else {
- bb_error_msg("getaddrinfo('%s') failed: %s", hostname, gai_strerror(rc));
+#if ENABLE_VERBOSE_RESOLUTION_ERRORS
+ bb_error_msg("can't resolve '%s': %s", hostname, gai_strerror(rc));
+#else
+ bb_error_msg("can't resolve '%s'", hostname);
+#endif
}
- freeaddrinfo(result);
+ if (ENABLE_FEATURE_CLEAN_UP)
+ freeaddrinfo(result);
return (rc != 0);
}
+/* lookup the default nameserver and display it */
+static void server_print(void)
+{
+ char *server;
+
+ server = xmalloc_sockaddr2dotted_noport((struct sockaddr*)&_res.nsaddr_list[0]);
+ /* I honestly don't know what to do if DNS server has _IPv6 address_.
+ * Probably it is listed in
+ * _res._u._ext_.nsaddrs[MAXNS] (of type "struct sockaddr_in6*" each)
+ * but how to find out whether resolver uses
+ * _res.nsaddr_list[] or _res._u._ext_.nsaddrs[], or both?
+ * Looks like classic design from hell, BIND-grade. Hard to surpass. */
+ print_host(server, "Server:");
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(server);
+ bb_putchar('\n');
+}
/* alter the global _res nameserver structure to use
an explicit dns server instead of what is in /etc/resolv.h */
}
}
-
-/* lookup the default nameserver and display it */
-static void server_print(void)
-{
- char str[INET6_ADDRSTRLEN];
-
- sockaddr_to_dotted((struct sockaddr*)&_res.nsaddr_list[0], str, sizeof(str));
- print_host(str, "Server:");
- puts("");
-}
-
-
+int nslookup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int nslookup_main(int argc, char **argv)
{
- /*
- * initialize DNS structure _res used in printing the default
- * name server and in the explicit name server option feature.
- */
-
- res_init();
-
- /*
- * We allow 1 or 2 arguments.
- * The first is the name to be looked up and the second is an
- * optional DNS server with which to do the lookup.
- * More than 3 arguments is an error to follow the pattern of the
- * standard nslookup
- */
+ /* We allow 1 or 2 arguments.
+ * The first is the name to be looked up and the second is an
+ * optional DNS server with which to do the lookup.
+ * More than 3 arguments is an error to follow the pattern of the
+ * standard nslookup */
if (argc < 2 || *argv[1] == '-' || argc > 3)
bb_show_usage();
- else if(argc == 3)
+
+ /* initialize DNS structure _res used in printing the default
+ * name server and in the explicit name server option feature. */
+ res_init();
+ /* rfc2133 says this enables IPv6 lookups */
+ /* (but it also says "may be enabled in /etc/resolv.conf|) */
+ /*_res.options |= RES_USE_INET6;*/
+
+ if (argc == 3)
set_default_dns(argv[2]);
server_print();
- return print_host(argv[1], "Name: ");
+ return print_host(argv[1], "Name:");
}
-
-/* $Id: nslookup.c,v 1.33 2004/10/13 07:25:01 andersen Exp $ */