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authorJun-ichiro itojun Hagino <itojun@itojun.org>1999-10-14 05:41:33 +0000
committerJun-ichiro itojun Hagino <itojun@itojun.org>1999-10-14 05:41:33 +0000
commit831497b33e358305b8f409882ec61097335b772d (patch)
tree70de51573eace737c5d829570dc33bd6b5261020 /inet_ntop.c
parent5ed4011c300a8c1688ee5aa1b184aa0d2fc54bc7 (diff)
use inet_pton() and inet_ntop(), which are RFC2553 standard function
for converting IPv[46] numeric notation to/from binary form. recent BIND includes those functions so fallback is not necessary on most of the platforms. sorry if it raises any portability problem on other platforms. remove partial inclusion of inet_ntop() in packet-ipv6.c. move ip6_to_str() to packet.c, it fits better there than packet-ipv6.c. svn path=/trunk/; revision=829
Diffstat (limited to 'inet_ntop.c')
-rw-r--r--inet_ntop.c211
1 files changed, 211 insertions, 0 deletions
diff --git a/inet_ntop.c b/inet_ntop.c
new file mode 100644
index 0000000000..009ac4e305
--- /dev/null
+++ b/inet_ntop.c
@@ -0,0 +1,211 @@
+/*
+ * 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS
+ * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
+ * CONSORTIUM 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.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char rcsid[] = "$Id: inet_ntop.c,v 1.1 1999/10/14 05:41:29 itojun Exp $";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifdef NEED_SNPRINTF_H
+# ifdef HAVE_STDARG_H
+# include <stdarg.h>
+# else
+# include <varargs.h>
+# endif
+# include "snprintf.h"
+#endif
+
+#ifndef NS_INADDRSZ
+#define NS_INADDRSZ 4
+#endif
+#ifndef NS_IN6ADDRSZ
+#define NS_IN6ADDRSZ 16
+#endif
+#ifndef NS_INT16SZ
+#define NS_INT16SZ 2
+#endif
+
+/*
+ * 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 __P((const u_char *src, char *dst, size_t size));
+static const char *inet_ntop6 __P((const u_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).
+ * author:
+ * Paul Vixie, 1996.
+ */
+const char *
+inet_ntop(af, src, dst, size)
+ int af;
+ const void *src;
+ char *dst;
+ size_t size;
+{
+ switch (af) {
+ case AF_INET:
+ return (inet_ntop4(src, dst, size));
+ case AF_INET6:
+ return (inet_ntop6(src, dst, size));
+ default:
+ 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 u_char* not an in_addr as input
+ * author:
+ * Paul Vixie, 1996.
+ */
+static const char *
+inet_ntop4(src, dst, size)
+ const u_char *src;
+ char *dst;
+ size_t size;
+{
+ static const char fmt[] = "%u.%u.%u.%u";
+ char tmp[sizeof "255.255.255.255"];
+
+ if (snprintf(tmp, sizeof(tmp), fmt, src[0], src[1], src[2], src[3]) > size) {
+ 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(src, dst, size)
+ const u_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"], *tp;
+ struct { int base, len; } best, cur;
+ u_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;
+ cur.base = -1;
+ 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 == 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) {
+ errno = ENOSPC;
+ return (NULL);
+ }
+ strcpy(dst, tmp);
+ return (dst);
+}