Edit File: ip_unix.c
/* ======================================================================== * Copyright 1988-2006 University of Washington * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * * ======================================================================== */ /* * Program: UNIX IPv6 routines * * Author: Mark Crispin * Networks and Distributed Computing * Computing & Communications * University of Washington * Administration Building, AG-44 * Seattle, WA 98195 * Internet: MRC@CAC.Washington.EDU * * Date: 18 December 2003 * Last Edited: 30 August 2006 */ /* * There is some amazingly bad design in IPv6 sockets. * * Supposedly, the new getnameinfo() and getaddrinfo() functions create an * abstraction that is not dependent upon IPv4 or IPv6. However, the * definition of getnameinfo() requires that the caller pass the length of * the sockaddr instead of deriving it from sa_family. The man page says * that there's an sa_len member in the sockaddr, but actually there isn't. * This means that any caller to getnameinfo() and getaddrinfo() has to know * the size for the protocol family used by that sockaddr. * * The new sockaddr_in6 is bigger than the generic sockaddr (which is what * connect(), accept(), bind(), getpeername(), getsockname(), etc. expect). * Rather than increase the size of sockaddr, there's a new sockaddr_storage * which is only usable for allocating space. */ #define SADRLEN sizeof (struct sockaddr_storage) #define SADR4(sadr) ((struct sockaddr_in *) sadr) #define SADR4LEN sizeof (struct sockaddr_in) #define SADR4ADR(sadr) SADR4 (sadr)->sin_addr #define ADR4LEN sizeof (struct in_addr) #define SADR4PORT(sadr) SADR4 (sadr)->sin_port #define SADR6(sadr) ((struct sockaddr_in6 *) sadr) #define SADR6LEN sizeof (struct sockaddr_in6) #define SADR6ADR(sadr) SADR6 (sadr)->sin6_addr #define ADR6LEN sizeof (struct in6_addr) #define SADR6PORT(sadr) SADR6 (sadr)->sin6_port /* IP abstraction layer */ char *ip_sockaddrtostring (struct sockaddr *sadr); long ip_sockaddrtoport (struct sockaddr *sadr); void *ip_stringtoaddr (char *text,size_t *len,int *family); struct sockaddr *ip_newsockaddr (size_t *len); struct sockaddr *ip_sockaddr (int family,void *adr,size_t adrlen, unsigned short port,size_t *len); char *ip_sockaddrtoname (struct sockaddr *sadr); void *ip_nametoaddr (char *name,size_t *len,int *family,char **canonical, void **next); /* Return IP address string from socket address * Accepts: socket address * Returns: IP address as name string */ char *ip_sockaddrtostring (struct sockaddr *sadr) { static char tmp[NI_MAXHOST]; switch (sadr->sa_family) { case PF_INET: /* IPv4 */ if (!getnameinfo (sadr,SADR4LEN,tmp,NI_MAXHOST,NIL,NIL,NI_NUMERICHOST)) return tmp; break; case PF_INET6: /* IPv6 */ if (!getnameinfo (sadr,SADR6LEN,tmp,NI_MAXHOST,NIL,NIL,NI_NUMERICHOST)) return tmp; break; } return "NON-IP"; } /* Return port from socket address * Accepts: socket address * Returns: port number or -1 if can't determine it */ long ip_sockaddrtoport (struct sockaddr *sadr) { switch (sadr->sa_family) { case PF_INET: return ntohs (SADR4PORT (sadr)); case PF_INET6: return ntohs (SADR6PORT (sadr)); } return -1; } /* Return IP address from string * Accepts: name string * pointer to returned length * pointer to returned address family * Returns: address if valid, length and family updated, or NIL */ void *ip_stringtoaddr (char *text,size_t *len,int *family) { char tmp[MAILTMPLEN]; static struct addrinfo *hints; struct addrinfo *ai; void *adr = NIL; if (!hints) { /* hints set up yet? */ hints = (struct addrinfo *) /* one-time setup */ memset (fs_get (sizeof (struct addrinfo)),0,sizeof (struct addrinfo)); hints->ai_family = AF_UNSPEC;/* allow any address family */ hints->ai_socktype = SOCK_STREAM; /* numeric name only */ hints->ai_flags = AI_NUMERICHOST; } /* case-independent lookup */ if (text && (strlen (text) < MAILTMPLEN) && (!getaddrinfo (lcase (strcpy (tmp,text)),NIL,hints,&ai))) { switch (*family = ai->ai_family) { case AF_INET: /* IPv4 */ adr = fs_get (*len = ADR4LEN); memcpy (adr,(void *) &SADR4ADR (ai->ai_addr),*len); break; case AF_INET6: /* IPv6 */ adr = fs_get (*len = ADR6LEN); memcpy (adr,(void *) &SADR6ADR (ai->ai_addr),*len); break; } freeaddrinfo (ai); /* free addrinfo */ } return adr; } /* Create a maximum-size socket address * Accepts: pointer to return maximum socket address length * Returns: new, empty socket address of maximum size */ struct sockaddr *ip_newsockaddr (size_t *len) { return (struct sockaddr *) memset (fs_get (SADRLEN),0,*len = SADRLEN); } /* Stuff a socket address * Accepts: address family * IPv4 address * length of address * port number * pointer to return socket address length * Returns: socket address */ struct sockaddr *ip_sockaddr (int family,void *adr,size_t adrlen, unsigned short port,size_t *len) { struct sockaddr *sadr = ip_newsockaddr (len); switch (family) { /* build socket address based upon family */ case AF_INET: /* IPv4 */ sadr->sa_family = PF_INET; /* copy host address */ memcpy (&SADR4ADR (sadr),adr,adrlen); /* copy port number in network format */ SADR4PORT (sadr) = htons (port); *len = SADR4LEN; break; case AF_INET6: /* IPv6 */ sadr->sa_family = PF_INET6; /* copy host address */ memcpy (&SADR6ADR (sadr),adr,adrlen); /* copy port number in network format */ SADR6PORT (sadr) = htons (port); *len = SADR6LEN; break; default: /* non-IP?? */ sadr->sa_family = PF_UNSPEC; break; } return sadr; } /* Return name from socket address * Accepts: socket address * Returns: canonical name for that address or NIL if none */ char *ip_sockaddrtoname (struct sockaddr *sadr) { static char tmp[NI_MAXHOST]; switch (sadr->sa_family) { case PF_INET: /* IPv4 */ if (!getnameinfo (sadr,SADR4LEN,tmp,NI_MAXHOST,NIL,NIL,NI_NAMEREQD)) return tmp; break; case PF_INET6: /* IPv6 */ if (!getnameinfo (sadr,SADR6LEN,tmp,NI_MAXHOST,NIL,NIL,NI_NAMEREQD)) return tmp; break; } return NIL; } /* Return address from name * Accepts: name or NIL to return next address * pointer to previous/returned length * pointer to previous/returned address family * pointer to previous/returned canonical name * pointer to previous/return state for next-address calls * Returns: address with length/family/canonical updated if needed, or NIL */ void *ip_nametoaddr (char *name,size_t *len,int *family,char **canonical, void **next) { struct addrinfo *cur = NIL; static struct addrinfo *hints; static struct addrinfo *ai = NIL; static char lcname[MAILTMPLEN]; if (!hints) { /* hints set up yet? */ hints = (struct addrinfo *) /* one-time setup */ memset (fs_get (sizeof (struct addrinfo)),0,sizeof (struct addrinfo)); /* allow any address family */ hints->ai_family = AF_UNSPEC; hints->ai_socktype = SOCK_STREAM; /* need canonical name */ hints->ai_flags = AI_CANONNAME; } if (name) { /* name supplied? */ if (ai) { freeaddrinfo (ai); /* free old addrinfo */ ai = NIL; } /* case-independent lookup */ if ((strlen (name) < MAILTMPLEN) && (!getaddrinfo (lcase (strcpy (lcname,name)),NIL,hints,&ai))) { cur = ai; /* current block */ if (canonical) /* set canonical name */ *canonical = cur->ai_canonname ? cur->ai_canonname : lcname; /* remember as next block */ if (next) *next = (void *) ai; } else { /* error */ cur = NIL; if (len) *len = 0; if (family) *family = 0; if (canonical) *canonical = NIL; if (next) *next = NIL; } } /* return next in series */ else if (next && (cur = ((struct addrinfo *) *next)->ai_next)) { *next = cur; /* set as last address */ /* set canonical in case changed */ if (canonical && cur->ai_canonname) *canonical = cur->ai_canonname; } if (cur) { /* got data? */ if (family) *family = cur->ai_family; switch (cur->ai_family) { case AF_INET: if (len) *len = ADR4LEN; return (void *) &SADR4ADR (cur->ai_addr); case AF_INET6: if (len) *len = ADR6LEN; return (void *) &SADR6ADR (cur->ai_addr); } } if (len) *len = 0; /* error return */ return NIL; }