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-rw-r--r--src/c-ares/inet_ntop.c208
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diff --git a/src/c-ares/inet_ntop.c b/src/c-ares/inet_ntop.c
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+++ b/src/c-ares/inet_ntop.c
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+/*
+ * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (c) 1996-1999 by Internet Software Consortium.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+ * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "ares_setup.h"
+
+#ifdef HAVE_NETINET_IN_H
+# include <netinet/in.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+# include <arpa/inet.h>
+#endif
+#ifdef HAVE_ARPA_NAMESER_H
+# include <arpa/nameser.h>
+#else
+# include "nameser.h"
+#endif
+#ifdef HAVE_ARPA_NAMESER_COMPAT_H
+# include <arpa/nameser_compat.h>
+#endif
+
+#include "ares.h"
+#include "ares_ipv6.h"
+
+#ifndef HAVE_INET_NTOP
+
+/*
+ * WARNING: Don't even consider trying to compile this on a system where
+ * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX.
+ */
+
+static const char *inet_ntop4(const unsigned char *src, char *dst, size_t size);
+static const char *inet_ntop6(const unsigned char *src, char *dst, size_t size);
+
+/* char *
+ * inet_ntop(af, src, dst, size)
+ * convert a network format address to presentation format.
+ * return:
+ * pointer to presentation format address (`dst'), or NULL (see errno).
+ * note:
+ * On Windows we store the error in the thread errno, not
+ * in the winsock error code. This is to avoid loosing the
+ * actual last winsock error. So use macro ERRNO to fetch the
+ * errno this funtion sets when returning NULL, not SOCKERRNO.
+ * author:
+ * Paul Vixie, 1996.
+ */
+const char *
+ares_inet_ntop(int af, const void *src, char *dst, ares_socklen_t size)
+{
+ switch (af) {
+ case AF_INET:
+ return (inet_ntop4(src, dst, (size_t)size));
+ case AF_INET6:
+ return (inet_ntop6(src, dst, (size_t)size));
+ default:
+ SET_ERRNO(EAFNOSUPPORT);
+ return (NULL);
+ }
+ /* NOTREACHED */
+}
+
+/* const char *
+ * inet_ntop4(src, dst, size)
+ * format an IPv4 address
+ * return:
+ * `dst' (as a const)
+ * notes:
+ * (1) uses no statics
+ * (2) takes a unsigned char* not an in_addr as input
+ * author:
+ * Paul Vixie, 1996.
+ */
+static const char *
+inet_ntop4(const unsigned char *src, char *dst, size_t size)
+{
+ static const char fmt[] = "%u.%u.%u.%u";
+ char tmp[sizeof("255.255.255.255")];
+
+ if ((size_t)sprintf(tmp, fmt, src[0], src[1], src[2], src[3]) >= size) {
+ SET_ERRNO(ENOSPC);
+ return (NULL);
+ }
+ strcpy(dst, tmp);
+ return (dst);
+}
+
+/* const char *
+ * inet_ntop6(src, dst, size)
+ * convert IPv6 binary address into presentation (printable) format
+ * author:
+ * Paul Vixie, 1996.
+ */
+static const char *
+inet_ntop6(const unsigned char *src, char *dst, size_t size)
+{
+ /*
+ * Note that int32_t and int16_t need only be "at least" large enough
+ * to contain a value of the specified size. On some systems, like
+ * Crays, there is no such thing as an integer variable with 16 bits.
+ * Keep this in mind if you think this function should have been coded
+ * to use pointer overlays. All the world's not a VAX.
+ */
+ char tmp[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")];
+ char *tp;
+ struct { int base, len; } best, cur;
+ unsigned int words[NS_IN6ADDRSZ / NS_INT16SZ];
+ int i;
+
+ /*
+ * Preprocess:
+ * Copy the input (bytewise) array into a wordwise array.
+ * Find the longest run of 0x00's in src[] for :: shorthanding.
+ */
+ memset(words, '\0', sizeof(words));
+ for (i = 0; i < NS_IN6ADDRSZ; i++)
+ words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
+ best.base = -1;
+ best.len = 0;
+ cur.base = -1;
+ cur.len = 0;
+ for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
+ if (words[i] == 0) {
+ if (cur.base == -1)
+ cur.base = i, cur.len = 1;
+ else
+ cur.len++;
+ } else {
+ if (cur.base != -1) {
+ if (best.base == -1 || cur.len > best.len)
+ best = cur;
+ cur.base = -1;
+ }
+ }
+ }
+ if (cur.base != -1) {
+ if (best.base == -1 || cur.len > best.len)
+ best = cur;
+ }
+ if (best.base != -1 && best.len < 2)
+ best.base = -1;
+
+ /*
+ * Format the result.
+ */
+ tp = tmp;
+ for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
+ /* Are we inside the best run of 0x00's? */
+ if (best.base != -1 && i >= best.base &&
+ i < (best.base + best.len)) {
+ if (i == best.base)
+ *tp++ = ':';
+ continue;
+ }
+ /* Are we following an initial run of 0x00s or any real hex? */
+ if (i != 0)
+ *tp++ = ':';
+ /* Is this address an encapsulated IPv4? */
+ if (i == 6 && best.base == 0 && (best.len == 6 ||
+ (best.len == 7 && words[7] != 0x0001) ||
+ (best.len == 5 && words[5] == 0xffff))) {
+ if (!inet_ntop4(src+12, tp, sizeof(tmp) - (tp - tmp)))
+ return (NULL);
+ tp += strlen(tp);
+ break;
+ }
+ tp += sprintf(tp, "%x", words[i]);
+ }
+ /* Was it a trailing run of 0x00's? */
+ if (best.base != -1 && (best.base + best.len) ==
+ (NS_IN6ADDRSZ / NS_INT16SZ))
+ *tp++ = ':';
+ *tp++ = '\0';
+
+ /*
+ * Check for overflow, copy, and we're done.
+ */
+ if ((size_t)(tp - tmp) > size) {
+ SET_ERRNO(ENOSPC);
+ return (NULL);
+ }
+ strcpy(dst, tmp);
+ return (dst);
+}
+
+#else /* HAVE_INET_NTOP */
+
+const char *
+ares_inet_ntop(int af, const void *src, char *dst, ares_socklen_t size)
+{
+ /* just relay this to the underlying function */
+ return inet_ntop(af, src, dst, size);
+}
+
+#endif /* HAVE_INET_NTOP */