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 */ 110 111 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 */ 137 138 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 */ 157 158 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