1 files changed, 135 insertions, 0 deletions

diff --git a/src/lib/libc/net/inet_net_ntop.c b/src/lib/libc/net/inet_net_ntop.c
new file mode 100644
index 0000000000..fc9071798a
--- /dev/null
+++ b/src/lib/libc/net/inet_net_ntop.c
@@ -0,0 +1,135 @@
+/*      $OpenBSD: inet_net_ntop.c,v 1.6 2005/08/06 20:30:03 espie 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/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+static char *inet_net_ntop_ipv4(const u_char *, int, char *, size_t);
+
+/*
+ * char *
+ * inet_net_ntop(af, src, bits, dst, size)
+ *      convert network number from network to presentation format.
+ *      generates CIDR style result always.
+ * return:
+ *      pointer to dst, or NULL if an error occurred (check errno).
+ * author:
+ *      Paul Vixie (ISC), July 1996
+ */
+char *
+inet_net_ntop(int af, const void *src, int bits, char *dst, size_t size)
+{
+        switch (af) {
+        case AF_INET:
+                return (inet_net_ntop_ipv4(src, bits, dst, size));
+        default:
+                errno = EAFNOSUPPORT;
+                return (NULL);
+        }
+}
+
+/*
+ * static char *
+ * inet_net_ntop_ipv4(src, bits, dst, size)
+ *      convert IPv4 network number from network to presentation format.
+ *      generates CIDR style result always.
+ * return:
+ *      pointer to dst, or NULL if an error occurred (check errno).
+ * note:
+ *      network byte order assumed.  this means 192.5.5.240/28 has
+ *      0x11110000 in its fourth octet.
+ * author:
+ *      Paul Vixie (ISC), July 1996
+ */
+static char *
+inet_net_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size)
+{
+        char *odst = dst;
+        u_int m;
+        int b;
+        char *ep;
+        int advance;
+
+        ep = dst + size;
+        if (ep <= dst)
+                goto emsgsize;
+
+        if (bits < 0 || bits > 32) {
+                errno = EINVAL;
+                return (NULL);
+        }
+        if (bits == 0) {
+                if (ep - dst < sizeof "0")
+                        goto emsgsize;
+                *dst++ = '0';
+                *dst = '\0';
+        }
+
+        /* Format whole octets. */
+        for (b = bits / 8; b > 0; b--) {
+                if (ep - dst < sizeof "255.")
+                        goto emsgsize;
+                advance = snprintf(dst, ep - dst, "%u", *src++);
+                if (advance <= 0 || advance >= ep - dst)
+                        goto emsgsize;
+                dst += advance;
+                if (b > 1) {
+                        if (dst + 1 >= ep)
+                                goto emsgsize;
+                        *dst++ = '.';
+                        *dst = '\0';
+                }
+        }
+
+        /* Format partial octet. */
+        b = bits % 8;
+        if (b > 0) {
+                if (ep - dst < sizeof ".255")
+                        goto emsgsize;
+                if (dst != odst)
+                        if (dst + 1 >= ep)
+                                goto emsgsize;
+                        *dst++ = '.';
+                m = ((1 << b) - 1) << (8 - b);
+                advance = snprintf(dst, ep - dst, "%u", *src & m);
+                if (advance <= 0 || advance >= ep - dst)
+                        goto emsgsize;
+                dst += advance;
+        }
+
+        /* Format CIDR /width. */
+        if (ep - dst < sizeof "/32")
+                goto emsgsize;
+        advance = snprintf(dst, ep - dst, "/%u", bits);
+        if (advance <= 0 || advance >= ep - dst)
+                goto emsgsize;
+        dst += advance;
+        return (odst);
+
+ emsgsize:
+        errno = EMSGSIZE;
+        return (NULL);
+}