wsutil/inet_addr.h

   1 /** @file
   2  *
   3  * Wireshark - Network traffic analyzer
   4  * By Gerald Combs <gerald@wireshark.org>
   5  * Copyright 1998 Gerald Combs
   6  *
   7  * SPDX-License-Identifier: GPL-2.0-or-later
   8  */
   9
  10 #ifndef __WS_INET_ADDR_H__
  11 #define __WS_INET_ADDR_H__
  12
  13 #include <wireshark.h>
  14
  15 #ifdef __cplusplus
  16 extern "C" {
  17 #endif /* __cplusplus */
  18
  19 typedef uint32_t ws_in4_addr;   /* 32 bit IPv4 address, in network byte order */
  20
  21 typedef struct e_in6_addr {
  22     uint8_t bytes[16];           /* 128 bit IPv6 address */
  23 } ws_in6_addr;
  24
  25
  26 /**
  27  * Unicast Local
  28  * Returns true if the address is in the 224.0.0.0/24 local network
  29  * control block
  30  */
  31 #define in4_addr_is_local_network_control_block(addr) \
  32   ((addr & 0xffffff00) == 0xe0000000)
  33
  34 /**
  35  * Multicast
  36  * Returns true if the address is in the 224.0.0.0/4 network block
  37  */
  38 #define in4_addr_is_multicast(addr) \
  39   ((addr & 0xf0000000) == 0xe0000000)
  40
  41 /**
  42  * Private address
  43  * Returns true if the address is in one of the three blocks reserved
  44  * for private IPv4 addresses by section 3 of RFC 1918, namely:
  45  * 10/8, 172.16/12, and 192.168/16
  46  */
  47 #define in4_addr_is_private(addr) \
  48   (((addr & 0xff000000) == 0x0a000000) || \
  49    ((addr & 0xfff00000) == 0xac100000) || \
  50    ((addr & 0xffff0000) == 0xc0a80000))
  51
  52 /**
  53  * Link-local address
  54  * Returns true if the address is in the 169.254/16 network block
  55  */
  56 #define in4_addr_is_link_local(addr) \
  57   ((addr & 0xffff0000) == 0xa9fe0000)
  58
  59 /**
  60  * Unicast Scope
  61  * Note that we must check topmost 10 bits only, not 16 bits (see RFC2373).
  62  */
  63 static inline bool
  64 in6_addr_is_linklocal(const ws_in6_addr *a)
  65 {
  66     return (a->bytes[0] == 0xfe) && ((a->bytes[1] & 0xc0) == 0x80);
  67 }
  68
  69 static inline bool
  70 in6_addr_is_sitelocal(const ws_in6_addr *a)
  71 {
  72     return (a->bytes[0] == 0xfe) && ((a->bytes[1] & 0xc0) == 0xc0);
  73 }
  74
  75 static inline bool in6_addr_is_uniquelocal(const ws_in6_addr *a)
  76 {
  77     return (a->bytes[0] & 0xfe) == 0xfc;
  78 }
  79
  80 /**
  81  * Multicast
  82  */
  83 static inline bool
  84 in6_addr_is_multicast(const ws_in6_addr *a)
  85 {
  86     return a->bytes[0] == 0xff;
  87 }
  88
  89 /*
  90  * These are the values specified by RFC 2133 and its successors for
  91  * INET_ADDRSTRLEN and INET6_ADDRSTRLEN.
  92  *
  93  * On UN*X systems, INET_ADDRSTRLEN and INET6_ADDRSTRLEN are defined
  94  * to the values from RFC 2133 and its successors.
  95  *
  96  * However, on Windows:
  97  *
  98  * There are APIs RtlIpv4AddressToStringEx(), which converts an
  99  * IPv4 address *and transport-layer port* to the address in the
 100  * standard text form, followed by a colon and the port number,
 101  * and RtlIpv6AddressToStringEx(), which converts an IPv6 address
 102  * *and scope ID and transport-layer port* to the address in the
 103  * standard text form, followed by a percent sign and the scope
 104  * ID (with the address and scope ID in square brackets), followed
 105  * by a colon and the port number.
 106  *
 107  * Instead of defining INET_ADDRSTRLEN_EX as 22 and INET6_ADDRSTRLEN_EX
 108  * as 65, and saying *those* were the buffer sizes to use for
 109  * RtlIpv4AddressToStringEx() and RtlIpv6AddressToStringEx(), they
 110  * defined INET_ADDRSTRLEN to be 22 and INET6_ADDRSTRLEN to be 65 - and
 111  * recommend using those as the size for the buffers passed to
 112  * RtlIpv4AddressToStringEx() and RtlIpv6AddressToStringEx().
 113  *
 114  * At least they document inet_ntop() as requiring a 16-byte or larger
 115  * buffer for IPv4 addresses and a 46-byte or larger buffer for
 116  * IPv6 addresses. For this reason, use hard-coded numeric constants rather than
 117  * INET_ADDRSTRLEN and INET6_ADDRSTRLEN.
 118  */
 119 #define WS_INET_ADDRSTRLEN      16
 120 #define WS_INET6_ADDRSTRLEN     46
 121
 122 /*
 123  * Utility for CIDR notation of subnets
 124  */
 125 #define WS_INET_CIDRADDRSTRLEN  19
 126
 127 /*
 128  * To check for errors set errno to zero before calling ws_inet_ntop{4,6}.
 129  * ENOSPC is set if the result exceeds the given buffer size.
 130  */
 131 WS_DLL_PUBLIC WS_RETNONNULL
 132 const char *
 133 ws_inet_ntop4(const void *src, char *dst, size_t dst_size);
 134
 135 WS_DLL_PUBLIC WS_RETNONNULL
 136 const char *
 137 ws_inet_ntop6(const void *src, char *dst, size_t dst_size);
 138
 139 WS_DLL_PUBLIC
 140 bool
 141 ws_inet_pton4(const char *src, ws_in4_addr *dst);
 142
 143 WS_DLL_PUBLIC
 144 bool
 145 ws_inet_pton6(const char *src, ws_in6_addr *dst);
 146
 147 #ifdef __cplusplus
 148 }
 149 #endif /* __cplusplus */
 150
 151 #endif