xref: /titanic_41/usr/src/uts/common/inet/ip/inet_ntop.c (revision 6f45ec7b0b964c3be967c4880e8867ac1e7763a5)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/cmn_err.h>
31 #include <sys/systm.h>
32 #include <sys/socket.h>
33 #include <sys/sunddi.h>
34 #include <netinet/in.h>
35 #include <inet/led.h>
36 
37 static void	convert2ascii(char *, const in6_addr_t *);
38 static char	*strchr_w(const char *, int);
39 static int	str2inet_addr(char *, ipaddr_t *);
40 
41 /*
42  * inet_ntop -- Convert an IPv4 or IPv6 address in binary form into
43  * printable form, and return a pointer to that string. Caller should
44  * provide a buffer of correct length to store string into.
45  * Note: this routine is kernel version of inet_ntop. It has similar
46  * format as inet_ntop() defined in rfc2553. But it does not do
47  * error handling operations exactly as rfc2553 defines. This function
48  * is used by kernel inet directory routines only for debugging.
49  * This inet_ntop() function, does not return NULL if third argument
50  * is NULL. The reason is simple that we don't want kernel to panic
51  * as the output of this function is directly fed to ip<n>dbg macro.
52  * Instead it uses a local buffer for destination address for
53  * those calls which purposely pass NULL ptr for the destination
54  * buffer. This function is thread-safe when the caller passes a non-
55  * null buffer with the third argument.
56  */
57 /* ARGSUSED */
58 char *
59 inet_ntop(int af, const void *addr, char *buf, int addrlen)
60 {
61 	static char local_buf[INET6_ADDRSTRLEN];
62 	static char *err_buf1 = "<badaddr>";
63 	static char *err_buf2 = "<badfamily>";
64 	in6_addr_t	*v6addr;
65 	uchar_t		*v4addr;
66 	char		*caddr;
67 
68 	/*
69 	 * We don't allow thread unsafe inet_ntop calls, they
70 	 * must pass a non-null buffer pointer. For DEBUG mode
71 	 * we use the ASSERT() and for non-debug kernel it will
72 	 * silently allow it for now. Someday we should remove
73 	 * the static buffer from this function.
74 	 */
75 
76 	ASSERT(buf != NULL);
77 	if (buf == NULL)
78 		buf = local_buf;
79 	buf[0] = '\0';
80 
81 	/* Let user know politely not to send NULL or unaligned addr */
82 	if (addr == NULL || !(OK_32PTR(addr))) {
83 #ifdef DEBUG
84 		cmn_err(CE_WARN, "inet_ntop: addr is <null> or unaligned");
85 #endif
86 		return (err_buf1);
87 	}
88 
89 
90 #define	UC(b)	(((int)b) & 0xff)
91 	switch (af) {
92 	case AF_INET:
93 		ASSERT(addrlen >= INET_ADDRSTRLEN);
94 		v4addr = (uchar_t *)addr;
95 		(void) sprintf(buf, "%03d.%03d.%03d.%03d",
96 		    UC(v4addr[0]), UC(v4addr[1]), UC(v4addr[2]), UC(v4addr[3]));
97 		return (buf);
98 
99 	case AF_INET6:
100 		ASSERT(addrlen >= INET6_ADDRSTRLEN);
101 		v6addr = (in6_addr_t *)addr;
102 		if (IN6_IS_ADDR_V4MAPPED(v6addr)) {
103 			caddr = (char *)addr;
104 			(void) sprintf(buf, "::ffff:%d.%d.%d.%d",
105 			    UC(caddr[12]), UC(caddr[13]),
106 			    UC(caddr[14]), UC(caddr[15]));
107 		} else if (IN6_IS_ADDR_V4COMPAT(v6addr)) {
108 			caddr = (char *)addr;
109 			(void) sprintf(buf, "::%d.%d.%d.%d",
110 			    UC(caddr[12]), UC(caddr[13]), UC(caddr[14]),
111 			    UC(caddr[15]));
112 		} else if (IN6_IS_ADDR_UNSPECIFIED(v6addr)) {
113 			(void) sprintf(buf, "::");
114 		} else {
115 			convert2ascii(buf, v6addr);
116 		}
117 		return (buf);
118 
119 	default:
120 		return (err_buf2);
121 	}
122 #undef UC
123 }
124 
125 /*
126  *
127  * v6 formats supported
128  * General format xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
129  * The short hand notation :: is used for COMPAT addr
130  * Other forms : fe80::xxxx:xxxx:xxxx:xxxx
131  */
132 static void
133 convert2ascii(char *buf, const in6_addr_t *addr)
134 {
135 	int		hexdigits;
136 	int		head_zero = 0;
137 	int		tail_zero = 0;
138 	/* tempbuf must be big enough to hold ffff:\0 */
139 	char		tempbuf[6];
140 	char		*ptr;
141 	uint16_t	*addr_component;
142 	size_t		len;
143 	boolean_t	first = B_FALSE;
144 	boolean_t	med_zero = B_FALSE;
145 	boolean_t	end_zero = B_FALSE;
146 
147 	addr_component = (uint16_t *)addr;
148 	ptr = buf;
149 
150 	/* First count if trailing zeroes higher in number */
151 	for (hexdigits = 0; hexdigits < 8; hexdigits++) {
152 		if (*addr_component == 0) {
153 			if (hexdigits < 4)
154 				head_zero++;
155 			else
156 				tail_zero++;
157 		}
158 		addr_component++;
159 	}
160 	addr_component = (uint16_t *)addr;
161 	if (tail_zero > head_zero && (head_zero + tail_zero) != 7)
162 		end_zero = B_TRUE;
163 
164 	for (hexdigits = 0; hexdigits < 8; hexdigits++) {
165 
166 		/* if entry is a 0 */
167 
168 		if (*addr_component == 0) {
169 			if (!first && *(addr_component + 1) == 0) {
170 				if (end_zero && (hexdigits < 4)) {
171 					*ptr++ = '0';
172 					*ptr++ = ':';
173 				} else {
174 					/*
175 					 * address starts with 0s ..
176 					 * stick in leading ':' of pair
177 					 */
178 					if (hexdigits == 0)
179 						*ptr++ = ':';
180 					/* add another */
181 					*ptr++ = ':';
182 					first = B_TRUE;
183 					med_zero = B_TRUE;
184 				}
185 			} else if (first && med_zero) {
186 				if (hexdigits == 7)
187 					*ptr++ = ':';
188 				addr_component++;
189 				continue;
190 			} else {
191 				*ptr++ = '0';
192 				*ptr++ = ':';
193 			}
194 			addr_component++;
195 			continue;
196 		}
197 		if (med_zero)
198 			med_zero = B_FALSE;
199 
200 		tempbuf[0] = '\0';
201 		(void) sprintf(tempbuf, "%x:", ntohs(*addr_component) & 0xffff);
202 		len = strlen(tempbuf);
203 		bcopy(tempbuf, ptr, len);
204 		ptr = ptr + len;
205 		addr_component++;
206 	}
207 	*--ptr = '\0';
208 }
209 
210 /*
211  * search for char c, terminate on trailing white space
212  */
213 static char *
214 strchr_w(const char *sp, int c)
215 {
216 	/* skip leading white space */
217 	while (*sp && (*sp == ' ' || *sp == '\t')) {
218 		sp++;
219 	}
220 
221 	do {
222 		if (*sp == (char)c)
223 			return ((char *)sp);
224 		if (*sp == ' ' || *sp == '\t')
225 			return (NULL);
226 	} while (*sp++);
227 	return (NULL);
228 }
229 
230 static int
231 str2inet_addr(char *cp, ipaddr_t *addrp)
232 {
233 	char *end;
234 	long byte;
235 	int i;
236 	ipaddr_t addr = 0;
237 
238 	for (i = 0; i < 4; i++) {
239 		if (ddi_strtol(cp, &end, 10, &byte) != 0 || byte < 0 ||
240 		    byte > 255) {
241 			return (0);
242 		}
243 		addr = (addr << 8) | (uint8_t)byte;
244 		if (i < 3) {
245 			if (*end != '.') {
246 				return (0);
247 			} else {
248 				cp = end + 1;
249 			}
250 		} else {
251 			cp = end;
252 		}
253 	}
254 	*addrp = addr;
255 	return (1);
256 }
257 
258 /*
259  * inet_pton: This function takes string format IPv4 or IPv6 address and
260  * converts it to binary form. The format of this function corresponds to
261  * inet_pton() in the socket library.
262  * It returns 0 for invalid IPv4 and IPv6 address
263  *            1 when successfully converts ascii to binary
264  *            -1 when af is not AF_INET or AF_INET6
265  */
266 int
267 inet_pton(int af, char *inp, void *outp)
268 {
269 	int i;
270 	long byte;
271 	char *end;
272 
273 	switch (af) {
274 	case AF_INET:
275 		return (str2inet_addr(inp, (ipaddr_t *)outp));
276 	case AF_INET6: {
277 		union v6buf_u {
278 			uint16_t v6words_u[8];
279 			in6_addr_t v6addr_u;
280 		} v6buf, *v6outp;
281 		uint16_t	*dbl_col = NULL;
282 		char lastbyte = NULL;
283 
284 		v6outp = (union v6buf_u *)outp;
285 
286 		if (strchr_w(inp, '.') != NULL) {
287 			/* v4 mapped or v4 compatable */
288 			if (strncmp(inp, "::ffff:", 7) == 0) {
289 				ipaddr_t ipv4_all_zeroes = 0;
290 				/* mapped - first init prefix and then fill */
291 				IN6_IPADDR_TO_V4MAPPED(ipv4_all_zeroes,
292 				    &v6outp->v6addr_u);
293 				return (str2inet_addr(inp + 7,
294 				    &(v6outp->v6addr_u.s6_addr32[3])));
295 			} else if (strncmp(inp, "::", 2) == 0) {
296 				/* v4 compatable - prefix all zeroes */
297 				bzero(&v6outp->v6addr_u, sizeof (in6_addr_t));
298 				return (str2inet_addr(inp + 2,
299 				    &(v6outp->v6addr_u.s6_addr32[3])));
300 			}
301 			return (0);
302 		}
303 		for (i = 0; i < 8; i++) {
304 			int error;
305 			/*
306 			 * if ddi_strtol() fails it could be because
307 			 * the string is "::".  That is valid and
308 			 * checked for below so just set the value to
309 			 * 0 and continue.
310 			 */
311 			if ((error = ddi_strtol(inp, &end, 16, &byte)) != 0) {
312 				if (error == ERANGE)
313 					return (0);
314 				byte = 0;
315 			}
316 			if (byte < 0 || byte > 0x0ffff) {
317 				return (0);
318 			}
319 			v6buf.v6words_u[i] = (uint16_t)byte;
320 			if (*end == NULL || i == 7) {
321 				inp = end;
322 				break;
323 			}
324 			if (inp == end) {	/* not a number must be */
325 				if (*inp == ':' &&
326 				    ((i == 0 && *(inp + 1) == ':') ||
327 				    lastbyte == ':')) {
328 					if (dbl_col) {
329 						return (0);
330 					}
331 					if (byte != 0)
332 						i++;
333 					dbl_col = &v6buf.v6words_u[i];
334 					if (i == 0)
335 						inp++;
336 				} else if (*inp == NULL || *inp == ' ' ||
337 				    *inp == '\t') {
338 					break;
339 				} else {
340 					return (0);
341 				}
342 			} else {
343 				inp = end;
344 			}
345 			if (*inp != ':') {
346 				return (0);
347 			}
348 			inp++;
349 			if (*inp == NULL || *inp == ' ' || *inp == '\t') {
350 				break;
351 			}
352 			lastbyte = *inp;
353 		}
354 		if (*inp != NULL && *inp != ' ' && *inp != '\t') {
355 			return (0);
356 		}
357 		/*
358 		 * v6words now contains the bytes we could translate
359 		 * dbl_col points to the word (should be 0) where
360 		 * a double colon was found
361 		 */
362 		if (i == 7) {
363 			v6outp->v6addr_u = v6buf.v6addr_u;
364 		} else {
365 			int rem;
366 			int word;
367 			int next;
368 			if (dbl_col == NULL) {
369 				return (0);
370 			}
371 			bzero(&v6outp->v6addr_u, sizeof (in6_addr_t));
372 			rem = dbl_col - &v6buf.v6words_u[0];
373 			for (next = 0; next < rem; next++) {
374 				v6outp->v6words_u[next] = v6buf.v6words_u[next];
375 			}
376 			next++;	/* skip dbl_col 0 */
377 			rem = i - rem;
378 			word = 8 - rem;
379 			while (rem > 0) {
380 				v6outp->v6words_u[word] = v6buf.v6words_u[next];
381 				word++;
382 				rem--;
383 				next++;
384 			}
385 		}
386 		return (1);	/* Success */
387 	}
388 	}	/* switch */
389 	return (-1);	/* return -1 for default case */
390 }
391