1/* vi: set sw=4 ts=4: */
2/*
3 * stolen from net-tools-1.59 and stripped down for busybox by
4 *                      Erik Andersen <andersen@codepoet.org>
5 *
6 * Heavily modified by Manuel Novoa III       Mar 12, 2001
7 *
8 *
9 */
10
11#include "libbb.h"
12#include "inet_common.h"
13
14int INET_resolve(const char *name, struct sockaddr_in *s_in, int hostfirst)
15{
16	struct hostent *hp;
17#if ENABLE_FEATURE_ETC_NETWORKS
18	struct netent *np;
19#endif
20
21	/* Grmpf. -FvK */
22	s_in->sin_family = AF_INET;
23	s_in->sin_port = 0;
24
25	/* Default is special, meaning 0.0.0.0. */
26	if (!strcmp(name, bb_str_default)) {
27		s_in->sin_addr.s_addr = INADDR_ANY;
28		return 1;
29	}
30	/* Look to see if it's a dotted quad. */
31	if (inet_aton(name, &s_in->sin_addr)) {
32		return 0;
33	}
34	/* If we expect this to be a hostname, try hostname database first */
35#ifdef DEBUG
36	if (hostfirst) {
37		bb_error_msg("gethostbyname(%s)", name);
38	}
39#endif
40	if (hostfirst) {
41		hp = gethostbyname(name);
42		if (hp != NULL) {
43			memcpy(&s_in->sin_addr, hp->h_addr_list[0],
44				sizeof(struct in_addr));
45			return 0;
46		}
47	}
48#if ENABLE_FEATURE_ETC_NETWORKS
49	/* Try the NETWORKS database to see if this is a known network. */
50#ifdef DEBUG
51	bb_error_msg("getnetbyname(%s)", name);
52#endif
53	np = getnetbyname(name);
54	if (np != NULL) {
55		s_in->sin_addr.s_addr = htonl(np->n_net);
56		return 1;
57	}
58#endif
59	if (hostfirst) {
60		/* Don't try again */
61		return -1;
62	}
63#ifdef DEBUG
64	res_init();
65	_res.options |= RES_DEBUG;
66#endif
67
68#ifdef DEBUG
69	bb_error_msg("gethostbyname(%s)", name);
70#endif
71	hp = gethostbyname(name);
72	if (hp == NULL) {
73		return -1;
74	}
75	memcpy(&s_in->sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
76	return 0;
77}
78
79
80/* numeric: & 0x8000: default instead of *,
81 *          & 0x4000: host instead of net,
82 *          & 0x0fff: don't resolve
83 */
84char *INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t netmask)
85{
86	/* addr-to-name cache */
87	struct addr {
88		struct addr *next;
89		struct sockaddr_in addr;
90		int host;
91		char name[1];
92	};
93	static struct addr *cache = NULL;
94
95	struct addr *pn;
96	char *name;
97	uint32_t ad, host_ad;
98	int host = 0;
99
100	/* Grmpf. -FvK */
101	if (s_in->sin_family != AF_INET) {
102#ifdef DEBUG
103		bb_error_msg("rresolve: unsupported address family %d!",
104				  s_in->sin_family);
105#endif
106		errno = EAFNOSUPPORT;
107		return NULL;
108	}
109	ad = s_in->sin_addr.s_addr;
110#ifdef DEBUG
111	bb_error_msg("rresolve: %08x, mask %08x, num %08x", (unsigned)ad, netmask, numeric);
112#endif
113	if (ad == INADDR_ANY) {
114		if ((numeric & 0x0FFF) == 0) {
115			if (numeric & 0x8000)
116				return xstrdup(bb_str_default);
117			return xstrdup("*");
118		}
119	}
120	if (numeric & 0x0FFF)
121		return xstrdup(inet_ntoa(s_in->sin_addr));
122
123	if ((ad & (~netmask)) != 0 || (numeric & 0x4000))
124		host = 1;
125	pn = cache;
126	while (pn) {
127		if (pn->addr.sin_addr.s_addr == ad && pn->host == host) {
128#ifdef DEBUG
129			bb_error_msg("rresolve: found %s %08x in cache",
130					  (host ? "host" : "net"), (unsigned)ad);
131#endif
132			return xstrdup(pn->name);
133		}
134		pn = pn->next;
135	}
136
137	host_ad = ntohl(ad);
138	name = NULL;
139	if (host) {
140		struct hostent *ent;
141#ifdef DEBUG
142		bb_error_msg("gethostbyaddr (%08x)", (unsigned)ad);
143#endif
144		ent = gethostbyaddr((char *) &ad, 4, AF_INET);
145		if (ent)
146			name = xstrdup(ent->h_name);
147	} else if (ENABLE_FEATURE_ETC_NETWORKS) {
148		struct netent *np;
149#ifdef DEBUG
150		bb_error_msg("getnetbyaddr (%08x)", (unsigned)host_ad);
151#endif
152		np = getnetbyaddr(host_ad, AF_INET);
153		if (np)
154			name = xstrdup(np->n_name);
155	}
156	if (!name)
157		name = xstrdup(inet_ntoa(s_in->sin_addr));
158	pn = xmalloc(sizeof(*pn) + strlen(name)); /* no '+ 1', it's already accounted for */
159	pn->next = cache;
160	pn->addr = *s_in;
161	pn->host = host;
162	strcpy(pn->name, name);
163	cache = pn;
164	return name;
165}
166
167#if ENABLE_FEATURE_IPV6
168
169int INET6_resolve(const char *name, struct sockaddr_in6 *sin6)
170{
171	struct addrinfo req, *ai;
172	int s;
173
174	memset(&req, '\0', sizeof req);
175	req.ai_family = AF_INET6;
176	s = getaddrinfo(name, NULL, &req, &ai);
177	if (s) {
178		bb_error_msg("getaddrinfo: %s: %d", name, s);
179		return -1;
180	}
181	memcpy(sin6, ai->ai_addr, sizeof(struct sockaddr_in6));
182	freeaddrinfo(ai);
183	return 0;
184}
185
186#ifndef IN6_IS_ADDR_UNSPECIFIED
187# define IN6_IS_ADDR_UNSPECIFIED(a) \
188	(((uint32_t *) (a))[0] == 0 && ((uint32_t *) (a))[1] == 0 && \
189	 ((uint32_t *) (a))[2] == 0 && ((uint32_t *) (a))[3] == 0)
190#endif
191
192
193char *INET6_rresolve(struct sockaddr_in6 *sin6, int numeric)
194{
195	char name[128];
196	int s;
197
198	/* Grmpf. -FvK */
199	if (sin6->sin6_family != AF_INET6) {
200#ifdef DEBUG
201		bb_error_msg("rresolve: unsupport address family %d!",
202				  sin6->sin6_family);
203#endif
204		errno = EAFNOSUPPORT;
205		return NULL;
206	}
207	if (numeric & 0x7FFF) {
208		inet_ntop(AF_INET6, &sin6->sin6_addr, name, sizeof(name));
209		return xstrdup(name);
210	}
211	if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
212		if (numeric & 0x8000)
213			return xstrdup(bb_str_default);
214		return xstrdup("*");
215	}
216
217	s = getnameinfo((struct sockaddr *) sin6, sizeof(struct sockaddr_in6),
218				name, sizeof(name), NULL, 0, 0);
219	if (s) {
220		bb_error_msg("getnameinfo failed");
221		return NULL;
222	}
223	return xstrdup(name);
224}
225
226#endif							/* CONFIG_FEATURE_IPV6 */
227