/Modules/getnameinfo.c

  1/*
  2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  3 * All rights reserved.
  4 * 
  5 * Redistribution and use in source and binary forms, with or without
  6 * modification, are permitted provided that the following conditions
  7 * are met:
  8 * 1. Redistributions of source code must retain the above copyright
  9 *    notice, this list of conditions and the following disclaimer.
 10 * 2. Redistributions in binary form must reproduce the above copyright
 11 *    notice, this list of conditions and the following disclaimer in the
 12 *    documentation and/or other materials provided with the distribution.
 13 * 3. Neither the name of the project nor the names of its contributors
 14 *    may be used to endorse or promote products derived from this software
 15 *    without specific prior written permission.
 16 * 
 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 27 * SUCH DAMAGE.
 28 */
 29
 30/*
 31 * Issues to be discussed:
 32 * - Thread safe-ness must be checked
 33 * - Return values.  There seems to be no standard for return value (RFC2133)
 34 *   but INRIA implementation returns EAI_xxx defined for getaddrinfo().
 35 */
 36
 37#if 0
 38#include <sys/types.h>
 39#include <sys/socket.h>
 40#include <netinet/in.h>
 41#include <arpa/inet.h>
 42#include <arpa/nameser.h>
 43#include <netdb.h>
 44#include <resolv.h>
 45#include <string.h>
 46#include <stddef.h>
 47
 48#include "addrinfo.h"
 49#endif
 50
 51#define SUCCESS 0
 52#define YES 1
 53#define NO  0
 54
 55static struct gni_afd {
 56	int a_af;
 57	int a_addrlen;
 58	int a_socklen;
 59	int a_off;
 60} gni_afdl [] = {
 61#ifdef ENABLE_IPV6
 62	{PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
 63		offsetof(struct sockaddr_in6, sin6_addr)},
 64#endif
 65	{PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
 66		offsetof(struct sockaddr_in, sin_addr)},
 67	{0, 0, 0},
 68};
 69
 70struct gni_sockinet {
 71	u_char	si_len;
 72	u_char	si_family;
 73	u_short	si_port;
 74};
 75
 76#define ENI_NOSOCKET 	0
 77#define ENI_NOSERVNAME	1
 78#define ENI_NOHOSTNAME	2
 79#define ENI_MEMORY	3
 80#define ENI_SYSTEM	4
 81#define ENI_FAMILY	5
 82#define ENI_SALEN	6
 83
 84/* forward declaration to make gcc happy */
 85int getnameinfo Py_PROTO((const struct sockaddr *, size_t, char *, size_t,
 86			  char *, size_t, int));
 87
 88int
 89getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 90	const struct sockaddr *sa;
 91	size_t salen;
 92	char *host;
 93	size_t hostlen;
 94	char *serv;
 95	size_t servlen;
 96	int flags;
 97{
 98	struct gni_afd *gni_afd;
 99	struct servent *sp;
100	struct hostent *hp;
101	u_short port;
102	int family, len, i;
103	char *addr, *p;
104	u_long v4a;
105#ifdef ENABLE_IPV6
106	u_char pfx;
107#endif
108	int h_error;
109	char numserv[512];
110	char numaddr[512];
111
112	if (sa == NULL)
113		return ENI_NOSOCKET;
114
115#ifdef HAVE_SOCKADDR_SA_LEN
116	len = sa->sa_len;
117	if (len != salen) return ENI_SALEN;
118#else
119	len = salen;
120#endif
121	
122	family = sa->sa_family;
123	for (i = 0; gni_afdl[i].a_af; i++)
124		if (gni_afdl[i].a_af == family) {
125			gni_afd = &gni_afdl[i];
126			goto found;
127		}
128	return ENI_FAMILY;
129	
130 found:
131	if (len != gni_afd->a_socklen) return ENI_SALEN;
132	
133	port = ((struct gni_sockinet *)sa)->si_port; /* network byte order */
134	addr = (char *)sa + gni_afd->a_off;
135
136	if (serv == NULL || servlen == 0) {
137		/* what we should do? */
138	} else if (flags & NI_NUMERICSERV) {
139		sprintf(numserv, "%d", ntohs(port));
140		if (strlen(numserv) > servlen)
141			return ENI_MEMORY;
142		strcpy(serv, numserv);
143	} else {
144		sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
145		if (sp) {
146			if (strlen(sp->s_name) > servlen)
147				return ENI_MEMORY;
148			strcpy(serv, sp->s_name);
149		} else
150			return ENI_NOSERVNAME;
151	}
152
153	switch (sa->sa_family) {
154	case AF_INET:
155		v4a = ((struct sockaddr_in *)sa)->sin_addr.s_addr;
156		if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
157			flags |= NI_NUMERICHOST;
158		v4a >>= IN_CLASSA_NSHIFT;
159		if (v4a == 0 || v4a == IN_LOOPBACKNET)
160			flags |= NI_NUMERICHOST;			
161		break;
162#ifdef ENABLE_IPV6
163	case AF_INET6:
164		pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr8[0];
165		if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
166			flags |= NI_NUMERICHOST;
167		break;
168#endif
169	}
170	if (host == NULL || hostlen == 0) {
171		/* what should we do? */
172	} else if (flags & NI_NUMERICHOST) {
173		if (inet_ntop(gni_afd->a_af, addr, numaddr, sizeof(numaddr))
174		    == NULL)
175			return ENI_SYSTEM;
176		if (strlen(numaddr) > hostlen)
177			return ENI_MEMORY;
178		strcpy(host, numaddr);
179	} else {
180#ifdef ENABLE_IPV6
181		hp = getipnodebyaddr(addr, gni_afd->a_addrlen, gni_afd->a_af, &h_error);
182#else
183		hp = gethostbyaddr(addr, gni_afd->a_addrlen, gni_afd->a_af);
184		h_error = h_errno;
185#endif
186
187		if (hp) {
188			if (flags & NI_NOFQDN) {
189				p = strchr(hp->h_name, '.');
190				if (p) *p = '\0';
191			}
192			if (strlen(hp->h_name) > hostlen) {
193#ifdef ENABLE_IPV6
194				freehostent(hp);
195#endif
196				return ENI_MEMORY;
197			}
198			strcpy(host, hp->h_name);
199#ifdef ENABLE_IPV6
200			freehostent(hp);
201#endif
202		} else {
203			if (flags & NI_NAMEREQD)
204				return ENI_NOHOSTNAME;
205			if (inet_ntop(gni_afd->a_af, addr, numaddr, sizeof(numaddr))
206			    == NULL)
207				return ENI_NOHOSTNAME;
208			if (strlen(numaddr) > hostlen)
209				return ENI_MEMORY;
210			strcpy(host, numaddr);
211		}
212	}
213	return SUCCESS;
214}