busybox/libbb/inet_common.c
2008-12-07 00:52:58 +00:00

222 lines
5.0 KiB
C

/* vi: set sw=4 ts=4: */
/*
* stolen from net-tools-1.59 and stripped down for busybox by
* Erik Andersen <andersen@codepoet.org>
*
* Heavily modified by Manuel Novoa III Mar 12, 2001
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include "inet_common.h"
int FAST_FUNC INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst)
{
struct hostent *hp;
#if ENABLE_FEATURE_ETC_NETWORKS
struct netent *np;
#endif
/* Grmpf. -FvK */
s_in->sin_family = AF_INET;
s_in->sin_port = 0;
/* Default is special, meaning 0.0.0.0. */
if (!strcmp(name, bb_str_default)) {
s_in->sin_addr.s_addr = INADDR_ANY;
return 1;
}
/* Look to see if it's a dotted quad. */
if (inet_aton(name, &s_in->sin_addr)) {
return 0;
}
/* If we expect this to be a hostname, try hostname database first */
#ifdef DEBUG
if (hostfirst) {
bb_error_msg("gethostbyname(%s)", name);
}
#endif
if (hostfirst) {
hp = gethostbyname(name);
if (hp != NULL) {
memcpy(&s_in->sin_addr, hp->h_addr_list[0],
sizeof(struct in_addr));
return 0;
}
}
#if ENABLE_FEATURE_ETC_NETWORKS
/* Try the NETWORKS database to see if this is a known network. */
#ifdef DEBUG
bb_error_msg("getnetbyname(%s)", name);
#endif
np = getnetbyname(name);
if (np != NULL) {
s_in->sin_addr.s_addr = htonl(np->n_net);
return 1;
}
#endif
if (hostfirst) {
/* Don't try again */
return -1;
}
#ifdef DEBUG
res_init();
_res.options |= RES_DEBUG;
bb_error_msg("gethostbyname(%s)", name);
#endif
hp = gethostbyname(name);
if (hp == NULL) {
return -1;
}
memcpy(&s_in->sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
return 0;
}
/* numeric: & 0x8000: default instead of *,
* & 0x4000: host instead of net,
* & 0x0fff: don't resolve
*/
char* FAST_FUNC INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t netmask)
{
/* addr-to-name cache */
struct addr {
struct addr *next;
struct sockaddr_in addr;
int host;
char name[1];
};
static struct addr *cache = NULL;
struct addr *pn;
char *name;
uint32_t ad, host_ad;
int host = 0;
if (s_in->sin_family != AF_INET) {
#ifdef DEBUG
bb_error_msg("rresolve: unsupported address family %d!",
s_in->sin_family);
#endif
errno = EAFNOSUPPORT;
return NULL;
}
ad = s_in->sin_addr.s_addr;
#ifdef DEBUG
bb_error_msg("rresolve: %08x, mask %08x, num %08x", (unsigned)ad, netmask, numeric);
#endif
if (ad == INADDR_ANY) {
if ((numeric & 0x0FFF) == 0) {
if (numeric & 0x8000)
return xstrdup(bb_str_default);
return xstrdup("*");
}
}
if (numeric & 0x0FFF)
return xstrdup(inet_ntoa(s_in->sin_addr));
if ((ad & (~netmask)) != 0 || (numeric & 0x4000))
host = 1;
pn = cache;
while (pn) {
if (pn->addr.sin_addr.s_addr == ad && pn->host == host) {
#ifdef DEBUG
bb_error_msg("rresolve: found %s %08x in cache",
(host ? "host" : "net"), (unsigned)ad);
#endif
return xstrdup(pn->name);
}
pn = pn->next;
}
host_ad = ntohl(ad);
name = NULL;
if (host) {
struct hostent *ent;
#ifdef DEBUG
bb_error_msg("gethostbyaddr (%08x)", (unsigned)ad);
#endif
ent = gethostbyaddr((char *) &ad, 4, AF_INET);
if (ent)
name = xstrdup(ent->h_name);
} else if (ENABLE_FEATURE_ETC_NETWORKS) {
struct netent *np;
#ifdef DEBUG
bb_error_msg("getnetbyaddr (%08x)", (unsigned)host_ad);
#endif
np = getnetbyaddr(host_ad, AF_INET);
if (np)
name = xstrdup(np->n_name);
}
if (!name)
name = xstrdup(inet_ntoa(s_in->sin_addr));
pn = xmalloc(sizeof(*pn) + strlen(name)); /* no '+ 1', it's already accounted for */
pn->next = cache;
pn->addr = *s_in;
pn->host = host;
strcpy(pn->name, name);
cache = pn;
return name;
}
#if ENABLE_FEATURE_IPV6
int FAST_FUNC INET6_resolve(const char *name, struct sockaddr_in6 *sin6)
{
struct addrinfo req, *ai;
int s;
memset(&req, '\0', sizeof req);
req.ai_family = AF_INET6;
s = getaddrinfo(name, NULL, &req, &ai);
if (s) {
bb_error_msg("getaddrinfo: %s: %d", name, s);
return -1;
}
memcpy(sin6, ai->ai_addr, sizeof(struct sockaddr_in6));
freeaddrinfo(ai);
return 0;
}
#ifndef IN6_IS_ADDR_UNSPECIFIED
# define IN6_IS_ADDR_UNSPECIFIED(a) \
(((uint32_t *) (a))[0] == 0 && ((uint32_t *) (a))[1] == 0 && \
((uint32_t *) (a))[2] == 0 && ((uint32_t *) (a))[3] == 0)
#endif
char* FAST_FUNC INET6_rresolve(struct sockaddr_in6 *sin6, int numeric)
{
char name[128];
int s;
if (sin6->sin6_family != AF_INET6) {
#ifdef DEBUG
bb_error_msg("rresolve: unsupport address family %d!",
sin6->sin6_family);
#endif
errno = EAFNOSUPPORT;
return NULL;
}
if (numeric & 0x7FFF) {
inet_ntop(AF_INET6, &sin6->sin6_addr, name, sizeof(name));
return xstrdup(name);
}
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
if (numeric & 0x8000)
return xstrdup(bb_str_default);
return xstrdup("*");
}
s = getnameinfo((struct sockaddr *) sin6, sizeof(struct sockaddr_in6),
name, sizeof(name), NULL, 0, 0);
if (s) {
bb_error_msg("getnameinfo failed");
return NULL;
}
return xstrdup(name);
}
#endif /* CONFIG_FEATURE_IPV6 */