1 /* $NetBSD: sock_addr.c,v 1.2 2017/02/14 01:16:49 christos Exp $ */
2
3 /*++
4 /* NAME
5 /* sock_addr 3
6 /* SUMMARY
7 /* sockaddr utilities
8 /* SYNOPSIS
9 /* #include <sock_addr.h>
10 /*
11 /* int sock_addr_cmp_addr(sa, sb)
12 /* const struct sockaddr *sa;
13 /* const struct sockaddr *sb;
14 /*
15 /* int sock_addr_cmp_port(sa, sb)
16 /* const struct sockaddr *sa;
17 /* const struct sockaddr *sb;
18 /*
19 /* int SOCK_ADDR_EQ_ADDR(sa, sb)
20 /* const struct sockaddr *sa;
21 /* const struct sockaddr *sb;
22 /*
23 /* int SOCK_ADDR_EQ_PORT(sa, sb)
24 /* const struct sockaddr *sa;
25 /* const struct sockaddr *sb;
26 /*
27 /* int sock_addr_in_loopback(sa)
28 /* const struct sockaddr *sa;
29 /* AUXILIARY MACROS
30 /* struct sockaddr *SOCK_ADDR_PTR(ptr)
31 /* unsigned char SOCK_ADDR_FAMILY(ptr)
32 /* unsigned char SOCK_ADDR_LEN(ptr)
33 /* unsigned short SOCK_ADDR_PORT(ptr)
34 /* unsigned short *SOCK_ADDR_PORTP(ptr)
35 /*
36 /* struct sockaddr_in *SOCK_ADDR_IN_PTR(ptr)
37 /* unsigned char SOCK_ADDR_IN_FAMILY(ptr)
38 /* unsigned short SOCK_ADDR_IN_PORT(ptr)
39 /* struct in_addr SOCK_ADDR_IN_ADDR(ptr)
40 /* struct in_addr IN_ADDR(ptr)
41 /*
42 /* struct sockaddr_in6 *SOCK_ADDR_IN6_PTR(ptr)
43 /* unsigned char SOCK_ADDR_IN6_FAMILY(ptr)
44 /* unsigned short SOCK_ADDR_IN6_PORT(ptr)
45 /* struct in6_addr SOCK_ADDR_IN6_ADDR(ptr)
46 /* struct in6_addr IN6_ADDR(ptr)
47 /* DESCRIPTION
48 /* These utilities take protocol-independent address structures
49 /* and perform protocol-dependent operations on structure members.
50 /* Some of the macros described here are called unsafe,
51 /* because they evaluate one or more arguments multiple times.
52 /*
53 /* sock_addr_cmp_addr() or sock_addr_cmp_port() compare the
54 /* address family and network address or port fields for
55 /* equality, and return indication of the difference between
56 /* their arguments: < 0 if the first argument is "smaller",
57 /* 0 for equality, and > 0 if the first argument is "larger".
58 /*
59 /* The unsafe macros SOCK_ADDR_EQ_ADDR() or SOCK_ADDR_EQ_PORT()
60 /* compare compare the address family and network address or
61 /* port fields for equality, and return non-zero when their
62 /* arguments differ.
63 /*
64 /* sock_addr_in_loopback() determines if the argument specifies
65 /* a loopback address.
66 /*
67 /* The SOCK_ADDR_PTR() macro casts a generic pointer to (struct
68 /* sockaddr *). The name is upper case for consistency not
69 /* safety. SOCK_ADDR_FAMILY() and SOCK_ADDR_LEN() return the
70 /* address family and length of the real structure that hides
71 /* inside a generic sockaddr structure. On systems where struct
72 /* sockaddr has no sa_len member, SOCK_ADDR_LEN() cannot be
73 /* used as lvalue. SOCK_ADDR_PORT() returns the IPv4 or IPv6
74 /* port number, in network byte order; it must not be used as
75 /* lvalue. SOCK_ADDR_PORTP() returns a pointer to the same.
76 /*
77 /* The macros SOCK_ADDR_IN{,6}_{PTR,FAMILY,PORT,ADDR}() cast
78 /* a generic pointer to a specific socket address structure
79 /* pointer, or access a specific socket address structure
80 /* member. These can be used as lvalues.
81 /*
82 /* The unsafe INADDR() and IN6_ADDR() macros dereference a
83 /* generic pointer to a specific address structure.
84 /* DIAGNOSTICS
85 /* Panic: unsupported address family.
86 /* LICENSE
87 /* .ad
88 /* .fi
89 /* The Secure Mailer license must be distributed with this software.
90 /* AUTHOR(S)
91 /* Wietse Venema
92 /* IBM T.J. Watson Research
93 /* P.O. Box 704
94 /* Yorktown Heights, NY 10598, USA
95 /*--*/
96
97 /* System library. */
98
99 #include <sys_defs.h>
100 #include <sys/socket.h>
101 #include <netinet/in.h>
102 #include <string.h>
103
104 /* Utility library. */
105
106 #include <msg.h>
107 #include <sock_addr.h>
108
109 /* sock_addr_cmp_addr - compare addresses for equality */
110
sock_addr_cmp_addr(const struct sockaddr * sa,const struct sockaddr * sb)111 int sock_addr_cmp_addr(const struct sockaddr *sa,
112 const struct sockaddr *sb)
113 {
114 if (sa->sa_family != sb->sa_family)
115 return (sa->sa_family - sb->sa_family);
116
117 /*
118 * With IPv6 address structures, assume a non-hostile implementation that
119 * stores the address as a contiguous sequence of bits. Any holes in the
120 * sequence would invalidate the use of memcmp().
121 */
122 if (sa->sa_family == AF_INET) {
123 return (SOCK_ADDR_IN_ADDR(sa).s_addr - SOCK_ADDR_IN_ADDR(sb).s_addr);
124 #ifdef HAS_IPV6
125 } else if (sa->sa_family == AF_INET6) {
126 return (memcmp((void *) &(SOCK_ADDR_IN6_ADDR(sa)),
127 (void *) &(SOCK_ADDR_IN6_ADDR(sb)),
128 sizeof(SOCK_ADDR_IN6_ADDR(sa))));
129 #endif
130 } else {
131 msg_panic("sock_addr_cmp_addr: unsupported address family %d",
132 sa->sa_family);
133 }
134 }
135
136 /* sock_addr_cmp_port - compare ports for equality */
137
sock_addr_cmp_port(const struct sockaddr * sa,const struct sockaddr * sb)138 int sock_addr_cmp_port(const struct sockaddr *sa,
139 const struct sockaddr *sb)
140 {
141 if (sa->sa_family != sb->sa_family)
142 return (sa->sa_family - sb->sa_family);
143
144 if (sa->sa_family == AF_INET) {
145 return (SOCK_ADDR_IN_PORT(sa) - SOCK_ADDR_IN_PORT(sb));
146 #ifdef HAS_IPV6
147 } else if (sa->sa_family == AF_INET6) {
148 return (SOCK_ADDR_IN6_PORT(sa) - SOCK_ADDR_IN6_PORT(sb));
149 #endif
150 } else {
151 msg_panic("sock_addr_cmp_port: unsupported address family %d",
152 sa->sa_family);
153 }
154 }
155
156 /* sock_addr_in_loopback - determine if address is loopback */
157
sock_addr_in_loopback(const struct sockaddr * sa)158 int sock_addr_in_loopback(const struct sockaddr *sa)
159 {
160 unsigned long inaddr;
161
162 if (sa->sa_family == AF_INET) {
163 inaddr = ntohl(SOCK_ADDR_IN_ADDR(sa).s_addr);
164 return (IN_CLASSA(inaddr)
165 && ((inaddr & IN_CLASSA_NET) >> IN_CLASSA_NSHIFT)
166 == IN_LOOPBACKNET);
167 #ifdef HAS_IPV6
168 } else if (sa->sa_family == AF_INET6) {
169 return (IN6_IS_ADDR_LOOPBACK(&SOCK_ADDR_IN6_ADDR(sa)));
170 #endif
171 } else {
172 msg_panic("sock_addr_in_loopback: unsupported address family %d",
173 sa->sa_family);
174 }
175 }
176