getnameinfo.c
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/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Issues to be discussed:
* - Thread safe-ness must be checked
* - Return values. There seems to be no standard for return value (RFC2133)
* but INRIA implementation returns EAI_xxx defined for getaddrinfo().
*/
#include "ruby/config.h"
#ifdef RUBY_EXTCONF_H
#include RUBY_EXTCONF_H
#endif
#include <stdio.h>
#include <sys/types.h>
#ifndef _WIN32
#if defined(__BEOS__) && !defined(__HAIKU__) && !defined(BONE)
# include <net/socket.h>
#else
# include <sys/socket.h>
#endif
#include <netinet/in.h>
#if defined(HAVE_ARPA_INET_H)
#include <arpa/inet.h>
#endif
#if defined(HAVE_ARPA_NAMESER_H)
#include <arpa/nameser.h>
#endif
#include <netdb.h>
#if defined(HAVE_RESOLV_H)
#include <resolv.h>
#endif
#endif
#ifdef _WIN32
#include <winsock2.h>
#include <ws2tcpip.h>
#define snprintf _snprintf
#endif
#include <string.h>
#include <stddef.h>
#ifdef SOCKS5
#include <socks.h>
#endif
#include "addrinfo.h"
#include "sockport.h"
#define SUCCESS 0
#define ANY 0
#define YES 1
#define NO 0
struct sockinet {
u_char si_len;
u_char si_family;
u_short si_port;
};
static struct afd {
int a_af;
int a_addrlen;
int a_socklen;
int a_off;
} afdl [] = {
#ifdef INET6
#define N_INET6 0
{PF_INET6, sizeof(struct in6_addr),
sizeof(struct sockaddr_in6),
offsetof(struct sockaddr_in6, sin6_addr)},
#define N_INET 1
#else
#define N_INET 0
#endif
{PF_INET, sizeof(struct in_addr),
sizeof(struct sockaddr_in),
offsetof(struct sockaddr_in, sin_addr)},
{0, 0, 0, 0},
};
#define ENI_NOSOCKET 0
#define ENI_NOSERVNAME 1
#define ENI_NOHOSTNAME 2
#define ENI_MEMORY 3
#define ENI_SYSTEM 4
#define ENI_FAMILY 5
#define ENI_SALEN 6
#ifndef HAVE_INET_NTOP
static const char *
inet_ntop(int af, const void *addr, char *numaddr, size_t numaddr_len)
{
#ifdef HAVE_INET_NTOA
struct in_addr in;
memcpy(&in.s_addr, addr, sizeof(in.s_addr));
snprintf(numaddr, numaddr_len, "%s", inet_ntoa(in));
#else
unsigned long x = ntohl(*(unsigned long*)addr);
snprintf(numaddr, numaddr_len, "%d.%d.%d.%d",
(int) (x>>24) & 0xff, (int) (x>>16) & 0xff,
(int) (x>> 8) & 0xff, (int) (x>> 0) & 0xff);
#endif
return numaddr;
}
#endif
int
getnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, socklen_t hostlen, char *serv, socklen_t servlen, int flags)
{
struct afd *afd;
struct hostent *hp;
u_short port;
int family, len, i;
char *addr, *p;
u_long v4a;
#ifdef INET6
u_char pfx;
#endif
int h_error;
char numserv[512];
char numaddr[512];
if (sa == NULL)
return ENI_NOSOCKET;
len = SA_LEN(sa);
if (len != salen) return ENI_SALEN;
family = sa->sa_family;
for (i = 0; afdl[i].a_af; i++)
if (afdl[i].a_af == family) {
afd = &afdl[i];
goto found;
}
return ENI_FAMILY;
found:
if (len != afd->a_socklen) return ENI_SALEN;
port = ((struct sockinet *)sa)->si_port; /* network byte order */
addr = (char *)sa + afd->a_off;
if (serv == NULL || servlen == 0) {
/* what we should do? */
} else if (flags & NI_NUMERICSERV) {
snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
if (strlen(numserv) + 1 > servlen)
return ENI_MEMORY;
strcpy(serv, numserv);
} else {
#if defined(HAVE_GETSERVBYPORT)
struct servent *sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
if (sp) {
if (strlen(sp->s_name) + 1 > servlen)
return ENI_MEMORY;
strcpy(serv, sp->s_name);
} else
return ENI_NOSERVNAME;
#else
return ENI_NOSERVNAME;
#endif
}
switch (sa->sa_family) {
case AF_INET:
v4a = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
flags |= NI_NUMERICHOST;
v4a >>= IN_CLASSA_NSHIFT;
if (v4a == 0)
flags |= NI_NUMERICHOST;
break;
#ifdef INET6
case AF_INET6:
#ifdef HAVE_ADDR8
pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
#else
pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
#endif
if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
flags |= NI_NUMERICHOST;
break;
#endif
}
if (host == NULL || hostlen == 0) {
/* what should we do? */
} else if (flags & NI_NUMERICHOST) {
if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
== NULL)
return ENI_SYSTEM;
if (strlen(numaddr) > hostlen)
return ENI_MEMORY;
strcpy(host, numaddr);
} else {
#ifdef INET6
hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
#else
hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
h_error = h_errno;
#endif
if (hp) {
if (flags & NI_NOFQDN) {
p = strchr(hp->h_name, '.');
if (p) *p = '\0';
}
if (strlen(hp->h_name) + 1 > hostlen) {
#ifdef INET6
freehostent(hp);
#endif
return ENI_MEMORY;
}
strcpy(host, hp->h_name);
#ifdef INET6
freehostent(hp);
#endif
} else {
if (flags & NI_NAMEREQD)
return ENI_NOHOSTNAME;
if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
== NULL)
return ENI_NOHOSTNAME;
if (strlen(numaddr) > hostlen)
return ENI_MEMORY;
strcpy(host, numaddr);
}
}
return SUCCESS;
}