init repo.

third_party/curl/lib/inet_ntop.c

@@ -0,0 +1,205 @@
+/*
+ * Copyright (C) 1996-2022  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.
+ *
+ * SPDX-License-Identifier: ISC
+ */
+/*
+ * Original code by Paul Vixie. "curlified" by Gisle Vanem.
+ */
+
+#include "curl_setup.h"
+
+#ifndef HAVE_INET_NTOP
+
+#ifdef HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+
+#include "inet_ntop.h"
+#include "curl_printf.h"
+
+#define IN6ADDRSZ       16
+#define INADDRSZ         4
+#define INT16SZ          2
+
+/*
+ * If USE_IPV6 is disabled, we still want to parse IPv6 addresses, so make
+ * sure we have _some_ value for AF_INET6 without polluting our fake value
+ * everywhere.
+ */
+#if !defined(USE_IPV6) && !defined(AF_INET6)
+#define AF_INET6 (AF_INET + 1)
+#endif
+
+/*
+ * Format an IPv4 address, more or less like inet_ntop().
+ *
+ * Returns `dst' (as a const)
+ * Note:
+ *  - uses no statics
+ *  - takes a unsigned char* not an in_addr as input
+ */
+static char *inet_ntop4 (const unsigned char *src, char *dst, size_t size)
+{
+  char tmp[sizeof("255.255.255.255")];
+  size_t len;
+
+  DEBUGASSERT(size >= 16);
+
+  tmp[0] = '\0';
+  (void)msnprintf(tmp, sizeof(tmp), "%d.%d.%d.%d",
+                  ((int)((unsigned char)src[0])) & 0xff,
+                  ((int)((unsigned char)src[1])) & 0xff,
+                  ((int)((unsigned char)src[2])) & 0xff,
+                  ((int)((unsigned char)src[3])) & 0xff);
+
+  len = strlen(tmp);
+  if(len == 0 || len >= size) {
+    errno = ENOSPC;
+    return (NULL);
+  }
+  strcpy(dst, tmp);
+  return dst;
+}
+
+/*
+ * Convert IPv6 binary address into presentation (printable) format.
+ */
+static 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;
+    int len;
+  } best, cur;
+  unsigned int words[IN6ADDRSZ / 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 < IN6ADDRSZ; i++)
+    words[i/2] |= ((unsigned int)src[i] << ((1 - (i % 2)) << 3));
+
+  best.base = -1;
+  cur.base  = -1;
+  best.len = 0;
+  cur.len = 0;
+
+  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) && (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 < (IN6ADDRSZ / 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)
+      *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))) {
+        errno = ENOSPC;
+        return (NULL);
+      }
+      tp += strlen(tp);
+      break;
+    }
+    tp += msnprintf(tp, 5, "%x", words[i]);
+  }
+
+  /* Was it a trailing run of 0x00's?
+   */
+  if(best.base != -1 && (best.base + best.len) == (IN6ADDRSZ / 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;
+}
+
+/*
+ * Convert a network format address to presentation format.
+ *
+ * Returns pointer to presentation format address (`buf').
+ * Returns NULL on error and errno set with the specific
+ * error, EAFNOSUPPORT or ENOSPC.
+ *
+ * On Windows we store the error in the thread errno, not
+ * in the winsock error code. This is to avoid losing the
+ * actual last winsock error. So when this function returns
+ * NULL, check errno not SOCKERRNO.
+ */
+char *Curl_inet_ntop(int af, const void *src, char *buf, size_t size)
+{
+  switch(af) {
+  case AF_INET:
+    return inet_ntop4((const unsigned char *)src, buf, size);
+  case AF_INET6:
+    return inet_ntop6((const unsigned char *)src, buf, size);
+  default:
+    errno = EAFNOSUPPORT;
+    return NULL;
+  }
+}
+#endif  /* HAVE_INET_NTOP */