1 /* vi: set sw=4 ts=4: */
2 /*
3  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
4  *
5  * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6  *
7  * Changes:
8  *
9  * Rani Assaf <rani@magic.metawire.com> 980929: resolve addresses
10  */
11 #include "libbb.h"
12 #include "utils.h"
13 #include "inet_common.h"
14 
get_hz(void)15 unsigned FAST_FUNC get_hz(void)
16 {
17 	static unsigned hz_internal;
18 	FILE *fp;
19 
20 	if (hz_internal)
21 		return hz_internal;
22 
23 	fp = fopen_for_read("/proc/net/psched");
24 	if (fp) {
25 		unsigned nom, denom;
26 
27 		if (fscanf(fp, "%*08x%*08x%08x%08x", &nom, &denom) == 2)
28 			if (nom == 1000000)
29 				hz_internal = denom;
30 		fclose(fp);
31 	}
32 	if (!hz_internal)
33 		hz_internal = bb_clk_tck();
34 	return hz_internal;
35 }
36 
get_unsigned(char * arg,const char * errmsg)37 unsigned FAST_FUNC get_unsigned(char *arg, const char *errmsg)
38 {
39 	unsigned long res;
40 	char *ptr;
41 
42 	if (*arg) {
43 		res = strtoul(arg, &ptr, 0);
44 //FIXME: "" will be accepted too, is it correct?!
45 		if (!*ptr && res <= UINT_MAX) {
46 			return res;
47 		}
48 	}
49 	invarg_1_to_2(arg, errmsg); /* does not return */
50 }
51 
get_u32(char * arg,const char * errmsg)52 uint32_t FAST_FUNC get_u32(char *arg, const char *errmsg)
53 {
54 	unsigned long res;
55 	char *ptr;
56 
57 	if (*arg) {
58 		res = strtoul(arg, &ptr, 0);
59 //FIXME: "" will be accepted too, is it correct?!
60 		if (!*ptr && res <= 0xFFFFFFFFUL) {
61 			return res;
62 		}
63 	}
64 	invarg_1_to_2(arg, errmsg); /* does not return */
65 }
66 
get_u16(char * arg,const char * errmsg)67 uint16_t FAST_FUNC get_u16(char *arg, const char *errmsg)
68 {
69 	unsigned long res;
70 	char *ptr;
71 
72 	if (*arg) {
73 		res = strtoul(arg, &ptr, 0);
74 //FIXME: "" will be accepted too, is it correct?!
75 		if (!*ptr && res <= 0xFFFF) {
76 			return res;
77 		}
78 	}
79 	invarg_1_to_2(arg, errmsg); /* does not return */
80 }
81 
get_addr_1(inet_prefix * addr,char * name,int family)82 int FAST_FUNC get_addr_1(inet_prefix *addr, char *name, int family)
83 {
84 	memset(addr, 0, sizeof(*addr));
85 
86 	if (strcmp(name, "default") == 0
87 	 || strcmp(name, "all") == 0
88 	 || strcmp(name, "any") == 0
89 	) {
90 		addr->family = family;
91 		addr->bytelen = (family == AF_INET6 ? 16 : 4);
92 		addr->bitlen = -1;
93 		return 0;
94 	}
95 
96 	if (strchr(name, ':')) {
97 		addr->family = AF_INET6;
98 		if (family != AF_UNSPEC && family != AF_INET6)
99 			return -1;
100 		if (inet_pton(AF_INET6, name, addr->data) <= 0)
101 			return -1;
102 		addr->bytelen = 16;
103 		addr->bitlen = -1;
104 		return 0;
105 	}
106 
107 	if (family != AF_UNSPEC && family != AF_INET)
108 		return -1;
109 
110 	/* Try to parse it as IPv4 */
111 	addr->family = AF_INET;
112 #if 0 /* Doesn't handle e.g. "10.10", for example, "ip r l root 10.10/16" */
113 	if (inet_pton(AF_INET, name, addr->data) <= 0)
114 		return -1;
115 #else
116 	{
117 		unsigned i = 0;
118 		unsigned n = 0;
119 		const char *cp = name - 1;
120 		while (*++cp) {
121 			if ((unsigned char)(*cp - '0') <= 9) {
122 				n = 10 * n + (unsigned char)(*cp - '0');
123 				if (n >= 256)
124 					return -1;
125 				((uint8_t*)addr->data)[i] = n;
126 				continue;
127 			}
128 			if (*cp == '.' && ++i <= 3) {
129 				n = 0;
130 				continue;
131 			}
132 			return -1;
133 		}
134 	}
135 #endif
136 	addr->bytelen = 4;
137 	addr->bitlen = -1;
138 
139 	return 0;
140 }
141 
get_prefix_1(inet_prefix * dst,char * arg,int family)142 static void get_prefix_1(inet_prefix *dst, char *arg, int family)
143 {
144 	char *slash;
145 
146 	memset(dst, 0, sizeof(*dst));
147 
148 	if (strcmp(arg, "default") == 0
149 	 || strcmp(arg, "all") == 0
150 	 || strcmp(arg, "any") == 0
151 	) {
152 		dst->family = family;
153 		/*dst->bytelen = 0; - done by memset */
154 		/*dst->bitlen = 0;*/
155 		return;
156 	}
157 
158 	slash = strchr(arg, '/');
159 	if (slash)
160 		*slash = '\0';
161 
162 	if (get_addr_1(dst, arg, family) == 0) {
163 		dst->bitlen = (dst->family == AF_INET6) ? 128 : 32;
164 		if (slash) {
165 			unsigned plen;
166 			inet_prefix netmask_pfx;
167 
168 			netmask_pfx.family = AF_UNSPEC;
169 			plen = bb_strtou(slash + 1, NULL, 0);
170 			if ((errno || plen > dst->bitlen)
171 			 && get_addr_1(&netmask_pfx, slash + 1, family) != 0
172 			) {
173 				goto bad;
174 			}
175 			if (netmask_pfx.family == AF_INET) {
176 				/* fill in prefix length of dotted quad */
177 				uint32_t mask = ntohl(netmask_pfx.data[0]);
178 				uint32_t host = ~mask;
179 
180 				/* a valid netmask must be 2^n - 1 */
181 				if (host & (host + 1))
182 					goto bad;
183 
184 				for (plen = 0; mask; mask <<= 1)
185 					++plen;
186 				if (plen > dst->bitlen)
187 					goto bad;
188 				/* dst->flags |= PREFIXLEN_SPECIFIED; */
189 			}
190 			dst->bitlen = plen;
191 		}
192 	}
193 
194 	if (slash)
195 		*slash = '/';
196 	return;
197  bad:
198 	bb_error_msg_and_die("an %s %s is expected rather than \"%s\"", "inet", "prefix", arg);
199 }
200 
get_addr(inet_prefix * dst,char * arg,int family)201 int FAST_FUNC get_addr(inet_prefix *dst, char *arg, int family)
202 {
203 	if (family == AF_PACKET) {
204 		bb_error_msg_and_die("\"%s\" may be inet %s, but it is not allowed in this context", arg, "address");
205 	}
206 	if (get_addr_1(dst, arg, family)) {
207 		bb_error_msg_and_die("an %s %s is expected rather than \"%s\"", "inet", "address", arg);
208 	}
209 	return 0;
210 }
211 
get_prefix(inet_prefix * dst,char * arg,int family)212 void FAST_FUNC get_prefix(inet_prefix *dst, char *arg, int family)
213 {
214 	if (family == AF_PACKET) {
215 		bb_error_msg_and_die("\"%s\" may be inet %s, but it is not allowed in this context", arg, "prefix");
216 	}
217 	get_prefix_1(dst, arg, family);
218 }
219 
get_addr32(char * name)220 uint32_t FAST_FUNC get_addr32(char *name)
221 {
222 	inet_prefix addr;
223 
224 	if (get_addr_1(&addr, name, AF_INET)) {
225 		bb_error_msg_and_die("an %s %s is expected rather than \"%s\"", "IP", "address", name);
226 	}
227 	return addr.data[0];
228 }
229 
next_arg(char ** argv)230 char** FAST_FUNC next_arg(char **argv)
231 {
232 	if (!*++argv)
233 		bb_simple_error_msg_and_die("command line is not complete, try \"help\"");
234 	return argv;
235 }
236 
invarg_1_to_2(const char * arg,const char * opt)237 void FAST_FUNC invarg_1_to_2(const char *arg, const char *opt)
238 {
239 	bb_error_msg_and_die(bb_msg_invalid_arg_to, arg, opt);
240 }
241 
duparg(const char * key,const char * arg)242 void FAST_FUNC duparg(const char *key, const char *arg)
243 {
244 	bb_error_msg_and_die("duplicate \"%s\": \"%s\" is the second value", key, arg);
245 }
246 
duparg2(const char * key,const char * arg)247 void FAST_FUNC duparg2(const char *key, const char *arg)
248 {
249 	bb_error_msg_and_die("either \"%s\" is duplicate, or \"%s\" is garbage", key, arg);
250 }
251 
inet_addr_match(const inet_prefix * a,const inet_prefix * b,int bits)252 int FAST_FUNC inet_addr_match(const inet_prefix *a, const inet_prefix *b, int bits)
253 {
254 	const uint32_t *a1 = a->data;
255 	const uint32_t *a2 = b->data;
256 	int words = bits >> 5;
257 
258 	bits &= 0x1f;
259 
260 	if (words)
261 		if (memcmp(a1, a2, words << 2))
262 			return -1;
263 
264 	if (bits) {
265 		uint32_t w1, w2;
266 		uint32_t mask;
267 
268 		w1 = a1[words];
269 		w2 = a2[words];
270 
271 		mask = htonl((0xffffffff) << (0x20 - bits));
272 
273 		if ((w1 ^ w2) & mask)
274 			return 1;
275 	}
276 
277 	return 0;
278 }
279 
rt_addr_n2a(int af,void * addr)280 const char* FAST_FUNC rt_addr_n2a(int af, void *addr)
281 {
282 	switch (af) {
283 	case AF_INET:
284 	case AF_INET6:
285 		return inet_ntop(af, addr,
286 			auto_string(xzalloc(INET6_ADDRSTRLEN)), INET6_ADDRSTRLEN
287 		);
288 	default:
289 		return "???";
290 	}
291 }
292 
293 #ifdef RESOLVE_HOSTNAMES
format_host(int af,int len,void * addr)294 const char* FAST_FUNC format_host(int af, int len, void *addr)
295 {
296 	if (resolve_hosts) {
297 		struct hostent *h_ent;
298 
299 		if (len <= 0) {
300 			switch (af) {
301 			case AF_INET:
302 				len = 4;
303 				break;
304 			case AF_INET6:
305 				len = 16;
306 				break;
307 			default:;
308 			}
309 		}
310 		if (len > 0) {
311 			h_ent = gethostbyaddr(addr, len, af);
312 			if (h_ent != NULL) {
313 				return auto_string(xstrdup(h_ent->h_name));
314 			}
315 		}
316 	}
317 	return rt_addr_n2a(af, addr);
318 }
319 #endif
320