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authorMartin Pieuchot <mpi@cvs.openbsd.org>2013-11-11 09:15:36 +0000
committerMartin Pieuchot <mpi@cvs.openbsd.org>2013-11-11 09:15:36 +0000
commit008162fc5772b17eb55b51289fe9ae44b5c5d62d (patch)
tree0558cf0b1dc36620d0fb8330346d37996f81f6b5 /sys/netinet/inet_ntop.c
parent4f2cab250b870ec4d2b3c1ddff37aa6feb1967bb (diff)
Replace most of our formating functions to convert IPv4/6 addresses from
network to presentation format to inet_ntop(). The few remaining functions will be soon converted. ok mikeb@, deraadt@ and moral support from henning@
Diffstat (limited to 'sys/netinet/inet_ntop.c')
-rw-r--r--sys/netinet/inet_ntop.c198
1 files changed, 198 insertions, 0 deletions
diff --git a/sys/netinet/inet_ntop.c b/sys/netinet/inet_ntop.c
new file mode 100644
index 00000000000..6a7944af579
--- /dev/null
+++ b/sys/netinet/inet_ntop.c
@@ -0,0 +1,198 @@
+/* $OpenBSD: inet_ntop.c,v 1.1 2013/11/11 09:15:34 mpi Exp $ */
+
+/* Copyright (c) 1996 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.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+#include <netinet/in.h>
+
+#define IN6ADDRSZ 16
+#define INT16SZ 2
+
+/*
+ * 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 u_char *src, char *dst, size_t size);
+#ifdef INET6
+static const char *inet_ntop6(const u_char *src, char *dst, size_t size);
+#endif /* INET6 */
+
+/* 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(int af, const void *src, char *dst, socklen_t size)
+{
+ switch (af) {
+ case AF_INET:
+ return (inet_ntop4(src, dst, (size_t)size));
+#ifdef INET6
+ case AF_INET6:
+ return (inet_ntop6(src, dst, (size_t)size));
+#endif /* INET6 */
+ default:
+ return (NULL);
+ }
+ /* NOTREACHED */
+}
+
+/* const char *
+ * inet_ntop4(src, dst, size)
+ * format an IPv4 address, more or less like inet_ntoa()
+ * 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(const u_char *src, char *dst, size_t size)
+{
+ static const char fmt[] = "%u.%u.%u.%u";
+ char tmp[sizeof "255.255.255.255"];
+ int l;
+
+ l = snprintf(tmp, size, fmt, src[0], src[1], src[2], src[3]);
+ if (l <= 0 || l >= size) {
+ return (NULL);
+ }
+ strlcpy(dst, tmp, size);
+ return (dst);
+}
+
+#ifdef INET6
+/* 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 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"];
+ char *tp, *ep;
+ struct { int base, len; } best, cur;
+ u_int words[IN6ADDRSZ / INT16SZ];
+ int i;
+ int advance;
+
+ /*
+ * 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 < IN6ADDRSZ; i++)
+ words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
+ best.base = -1;
+ cur.base = -1;
+ for (i = 0; i < (IN6ADDRSZ / 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;
+ ep = tmp + sizeof(tmp);
+ for (i = 0; i < (IN6ADDRSZ / INT16SZ) && tp < ep; 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) {
+ if (tp + 1 >= ep)
+ return (NULL);
+ *tp++ = ':';
+ }
+ continue;
+ }
+ /* Are we following an initial run of 0x00s or any real hex? */
+ if (i != 0) {
+ if (tp + 1 >= ep)
+ return (NULL);
+ *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, (size_t)(ep - tp)))
+ return (NULL);
+ tp += strlen(tp);
+ break;
+ }
+ advance = snprintf(tp, ep - tp, "%x", words[i]);
+ if (advance <= 0 || advance >= ep - tp)
+ return (NULL);
+ tp += advance;
+ }
+ /* Was it a trailing run of 0x00's? */
+ if (best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / INT16SZ)) {
+ if (tp + 1 >= ep)
+ return (NULL);
+ *tp++ = ':';
+ }
+ if (tp + 1 >= ep)
+ return (NULL);
+ *tp++ = '\0';
+
+ /*
+ * Check for overflow, copy, and we're done.
+ */
+ if ((size_t)(tp - tmp) > size) {
+ return (NULL);
+ }
+ strlcpy(dst, tmp, size);
+ return (dst);
+}
+#endif /* INET6 */