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 * Licensed under GPLv2, see file LICENSE in this source tree.
9 */
10
11 #include "libbb.h"
12 #include "inet_common.h"
13
INET_resolve(const char * name,struct sockaddr_in * s_in,int hostfirst)14 int FAST_FUNC 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, "default") == 0) {
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 if (hostfirst) {
36 #ifdef DEBUG
37 bb_error_msg("gethostbyname(%s)", name);
38 #endif
39 hp = gethostbyname(name);
40 if (hp) {
41 memcpy(&s_in->sin_addr, hp->h_addr_list[0],
42 sizeof(struct in_addr));
43 return 0;
44 }
45 }
46 #if ENABLE_FEATURE_ETC_NETWORKS
47 /* Try the NETWORKS database to see if this is a known network. */
48 #ifdef DEBUG
49 bb_error_msg("getnetbyname(%s)", name);
50 #endif
51 np = getnetbyname(name);
52 if (np) {
53 s_in->sin_addr.s_addr = htonl(np->n_net);
54 return 1;
55 }
56 #endif
57 if (hostfirst) {
58 /* Don't try again */
59 return -1;
60 }
61 #ifdef DEBUG
62 res_init();
63 _res.options |= RES_DEBUG;
64 bb_error_msg("gethostbyname(%s)", name);
65 #endif
66 hp = gethostbyname(name);
67 if (!hp) {
68 return -1;
69 }
70 memcpy(&s_in->sin_addr, hp->h_addr_list[0], sizeof(struct in_addr));
71 return 0;
72 }
73
74
75 /* numeric: & 0x8000: "default" instead of "*",
76 * & 0x4000: host instead of net,
77 * & 0x0fff: don't resolve
78 */
INET_rresolve(struct sockaddr_in * s_in,int numeric,uint32_t netmask)79 char* FAST_FUNC INET_rresolve(struct sockaddr_in *s_in, int numeric, uint32_t netmask)
80 {
81 /* addr-to-name cache */
82 struct addr {
83 struct addr *next;
84 uint32_t nip;
85 smallint is_host;
86 char name[1];
87 };
88 static struct addr *cache = NULL;
89
90 struct addr *pn;
91 char *name;
92 uint32_t nip;
93 smallint is_host;
94
95 if (s_in->sin_family != AF_INET) {
96 #ifdef DEBUG
97 bb_error_msg("rresolve: unsupported address family %d!",
98 s_in->sin_family);
99 #endif
100 errno = EAFNOSUPPORT;
101 return NULL;
102 }
103 nip = s_in->sin_addr.s_addr;
104 #ifdef DEBUG
105 bb_error_msg("rresolve: %08x mask:%08x num:%08x", (unsigned)nip, netmask, numeric);
106 #endif
107 if (numeric & 0x0FFF)
108 return xmalloc_sockaddr2dotted_noport((void*)s_in);
109 if (nip == INADDR_ANY) {
110 if (numeric & 0x8000)
111 return xstrdup("default");
112 return xstrdup("*");
113 }
114
115 is_host = ((nip & (~netmask)) != 0 || (numeric & 0x4000));
116
117 pn = cache;
118 while (pn) {
119 if (pn->nip == nip && pn->is_host == is_host) {
120 #ifdef DEBUG
121 bb_error_msg("rresolve: found %s %08x in cache",
122 (is_host ? "host" : "net"), (unsigned)nip);
123 #endif
124 return xstrdup(pn->name);
125 }
126 pn = pn->next;
127 }
128
129 name = NULL;
130 if (is_host) {
131 #ifdef DEBUG
132 bb_error_msg("sockaddr2host_noport(%08x)", (unsigned)nip);
133 #endif
134 name = xmalloc_sockaddr2host_noport((void*)s_in);
135 } else if (ENABLE_FEATURE_ETC_NETWORKS) {
136 struct netent *np;
137 #ifdef DEBUG
138 bb_error_msg("getnetbyaddr(%08x)", (unsigned)ntohl(nip));
139 #endif
140 np = getnetbyaddr(ntohl(nip), AF_INET);
141 if (np)
142 name = xstrdup(np->n_name);
143 }
144 if (!name)
145 name = xmalloc_sockaddr2dotted_noport((void*)s_in);
146
147 pn = xmalloc(sizeof(*pn) + strlen(name)); /* no '+ 1', it's already accounted for */
148 pn->next = cache;
149 pn->nip = nip;
150 pn->is_host = is_host;
151 strcpy(pn->name, name);
152 cache = pn;
153
154 return name;
155 }
156
157 #if ENABLE_FEATURE_IPV6
158
INET6_resolve(const char * name,struct sockaddr_in6 * sin6)159 int FAST_FUNC INET6_resolve(const char *name, struct sockaddr_in6 *sin6)
160 {
161 struct addrinfo req, *ai = NULL;
162 int s;
163
164 memset(&req, 0, sizeof(req));
165 req.ai_family = AF_INET6;
166 s = getaddrinfo(name, NULL, &req, &ai);
167 if (s != 0) {
168 bb_error_msg("getaddrinfo: %s: %d", name, s);
169 return -1;
170 }
171 memcpy(sin6, ai->ai_addr, sizeof(*sin6));
172 freeaddrinfo(ai);
173 return 0;
174 }
175
176 #ifndef IN6_IS_ADDR_UNSPECIFIED
177 # define IN6_IS_ADDR_UNSPECIFIED(a) \
178 (((uint32_t *) (a))[0] == 0 && ((uint32_t *) (a))[1] == 0 && \
179 ((uint32_t *) (a))[2] == 0 && ((uint32_t *) (a))[3] == 0)
180 #endif
181
182
INET6_rresolve(struct sockaddr_in6 * sin6,int numeric)183 char* FAST_FUNC INET6_rresolve(struct sockaddr_in6 *sin6, int numeric)
184 {
185 if (sin6->sin6_family != AF_INET6) {
186 #ifdef DEBUG
187 bb_error_msg("rresolve: unsupported address family %d!",
188 sin6->sin6_family);
189 #endif
190 errno = EAFNOSUPPORT;
191 return NULL;
192 }
193 if (numeric & 0x7FFF) {
194 return xmalloc_sockaddr2dotted_noport((void*)sin6);
195 }
196 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
197 if (numeric & 0x8000)
198 return xstrdup("default");
199 return xstrdup("*");
200 }
201
202 return xmalloc_sockaddr2host_noport((void*)sin6);
203 }
204
205 #endif /* CONFIG_FEATURE_IPV6 */
206