[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/busybox/src/networking/nslookup.c b/ap/app/busybox/src/networking/nslookup.c
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+++ b/ap/app/busybox/src/networking/nslookup.c
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+/* vi: set sw=4 ts=4: */
+/*
+ * Mini nslookup implementation for busybox
+ *
+ * Copyright (C) 1999,2000 by Lineo, inc. and John Beppu
+ * Copyright (C) 1999,2000,2001 by John Beppu <beppu@codepoet.org>
+ *
+ * Correct default name server display and explicit name server option
+ * added by Ben Zeckel <bzeckel@hmc.edu> June 2001
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//usage:#define nslookup_trivial_usage
+//usage:       "[HOST] [SERVER]"
+//usage:#define nslookup_full_usage "\n\n"
+//usage:       "Query the nameserver for the IP address of the given HOST\n"
+//usage:       "optionally using a specified DNS server"
+//usage:
+//usage:#define nslookup_example_usage
+//usage:       "$ nslookup localhost\n"
+//usage:       "Server:     default\n"
+//usage:       "Address:    default\n"
+//usage:       "\n"
+//usage:       "Name:       debian\n"
+//usage:       "Address:    127.0.0.1\n"
+
+#include <resolv.h>
+#include "libbb.h"
+
+
+/*
+ * I'm only implementing non-interactive mode;
+ * I totally forgot nslookup even had an interactive mode.
+ *
+ * This applet is the only user of res_init(). Without it,
+ * you may avoid pulling in _res global from libc.
+ */
+
+/* Examples of 'standard' nslookup output
+ * $ nslookup yahoo.com
+ * Server:         128.193.0.10
+ * Address:        128.193.0.10#53
+ *
+ * Non-authoritative answer:
+ * Name:   yahoo.com
+ * Address: 216.109.112.135
+ * Name:   yahoo.com
+ * Address: 66.94.234.13
+ *
+ * $ nslookup 204.152.191.37
+ * Server:         128.193.4.20
+ * Address:        128.193.4.20#53
+ *
+ * Non-authoritative answer:
+ * 37.191.152.204.in-addr.arpa     canonical name = 37.32-27.191.152.204.in-addr.arpa.
+ * 37.32-27.191.152.204.in-addr.arpa       name = zeus-pub2.kernel.org.
+ *
+ * Authoritative answers can be found from:
+ * 32-27.191.152.204.in-addr.arpa  nameserver = ns1.kernel.org.
+ * 32-27.191.152.204.in-addr.arpa  nameserver = ns2.kernel.org.
+ * 32-27.191.152.204.in-addr.arpa  nameserver = ns3.kernel.org.
+ * ns1.kernel.org  internet address = 140.211.167.34
+ * ns2.kernel.org  internet address = 204.152.191.4
+ * ns3.kernel.org  internet address = 204.152.191.36
+ */
+
+static int print_host(const char *hostname, const char *header)
+{
+	/* We can't use xhost2sockaddr() - we want to get ALL addresses,
+	 * not just one */
+	struct addrinfo *result = NULL;
+	int rc;
+	struct addrinfo hint;
+
+	memset(&hint, 0 , sizeof(hint));
+	/* hint.ai_family = AF_UNSPEC; - zero anyway */
+	/* Needed. Or else we will get each address thrice (or more)
+	 * for each possible socket type (tcp,udp,raw...): */
+	hint.ai_socktype = SOCK_STREAM;
+	// hint.ai_flags = AI_CANONNAME;
+	rc = getaddrinfo(hostname, NULL /*service*/, &hint, &result);
+
+	if (rc == 0) {
+		struct addrinfo *cur = result;
+		unsigned cnt = 0;
+
+		printf("%-10s %s\n", header, hostname);
+		// puts(cur->ai_canonname); ?
+		while (cur) {
+			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 {
+#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
+	}
+	if (ENABLE_FEATURE_CLEAN_UP && result)
+		freeaddrinfo(result);
+	return (rc != 0);
+}
+
+/* lookup the default nameserver and display it */
+static void server_print(void)
+{
+#ifndef __UC_LIBC__
+	char *server;
+	struct sockaddr *sa;
+
+#if ENABLE_FEATURE_IPV6
+	sa = (struct sockaddr*)_res._u._ext.nsaddrs[0];
+	if (!sa)
+#endif
+		sa = (struct sockaddr*)&_res.nsaddr_list[0];
+	server = xmalloc_sockaddr2dotted_noport(sa);
+
+	print_host(server, "Server:");
+	if (ENABLE_FEATURE_CLEAN_UP)
+		free(server);
+	bb_putchar('\n');
+#endif
+}
+
+/* alter the global _res nameserver structure to use
+   an explicit dns server instead of what is in /etc/resolv.conf */
+static void set_default_dns(const char *server)
+{
+	len_and_sockaddr *lsa;
+
+	/* NB: this works even with, say, "[::1]:5353"! :) */
+	lsa = xhost2sockaddr(server, 53);
+
+	if (lsa->u.sa.sa_family == AF_INET) {
+		_res.nscount = 1;
+		/* struct copy */
+		_res.nsaddr_list[0] = lsa->u.sin;
+	}
+#if ENABLE_FEATURE_IPV6
+	/* Hoped libc can cope with IPv4 address there too.
+	 * No such luck, glibc 2.4 segfaults even with IPv6,
+	 * maybe I misunderstand how to make glibc use IPv6 addr?
+	 * (uclibc 0.9.31+ should work) */
+	if (lsa->u.sa.sa_family == AF_INET6) {
+		// glibc neither SEGVs nor sends any dgrams with this
+		// (strace shows no socket ops):
+		//_res.nscount = 0;
+		_res._u._ext.nscount = 1;
+		/* store a pointer to part of malloc'ed lsa */
+		_res._u._ext.nsaddrs[0] = &lsa->u.sin6;
+		/* must not free(lsa)! */
+	}
+#endif
+}
+
+int nslookup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int nslookup_main(int argc, char **argv)
+{
+	/* 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 (!argv[1] || argv[1][0] == '-' || argc > 3)
+		bb_show_usage();
+
+#ifndef __UC_LIBC__
+	/* initialize DNS structure _res used in printing the default
+	 * name server and in the explicit name server option feature. */
+	res_init();
+#endif
+
+	/* rfc2133 says this enables IPv6 lookups */
+	/* (but it also says "may be enabled in /etc/resolv.conf") */
+	/*_res.options |= RES_USE_INET6;*/
+
+	if (argv[2])
+		set_default_dns(argv[2]);
+
+	server_print();
+	return print_host(argv[1], "Name:");
+}