1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Generic address resultion entity
7 * net_ratelimit Andi Kleen
8 * in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
10 * Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
13 #include <linux/module.h>
14 #include <linux/jiffies.h>
15 #include <linux/kernel.h>
16 #include <linux/ctype.h>
17 #include <linux/inet.h>
19 #include <linux/net.h>
20 #include <linux/string.h>
21 #include <linux/types.h>
22 #include <linux/percpu.h>
23 #include <linux/init.h>
24 #include <linux/ratelimit.h>
25 #include <linux/socket.h>
28 #include <net/net_ratelimit.h>
31 #include <asm/byteorder.h>
32 #include <linux/uaccess.h>
34 DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
36 * All net warning printk()s should be guarded by this function.
38 int net_ratelimit(void)
40 return __ratelimit(&net_ratelimit_state);
42 EXPORT_SYMBOL(net_ratelimit);
45 * Convert an ASCII string to binary IP.
46 * This is outside of net/ipv4/ because various code that uses IP addresses
47 * is otherwise not dependent on the TCP/IP stack.
50 __be32 in_aton(const char *str)
57 for (i = 0; i < 4; i++) {
61 while (*str != '\0' && *str != '.' && *str != '\n') {
73 EXPORT_SYMBOL(in_aton);
75 #define IN6PTON_XDIGIT 0x00010000
76 #define IN6PTON_DIGIT 0x00020000
77 #define IN6PTON_COLON_MASK 0x00700000
78 #define IN6PTON_COLON_1 0x00100000 /* single : requested */
79 #define IN6PTON_COLON_2 0x00200000 /* second : requested */
80 #define IN6PTON_COLON_1_2 0x00400000 /* :: requested */
81 #define IN6PTON_DOT 0x00800000 /* . */
82 #define IN6PTON_DELIM 0x10000000
83 #define IN6PTON_NULL 0x20000000 /* first/tail */
84 #define IN6PTON_UNKNOWN 0x40000000
86 static inline int xdigit2bin(char c, int delim)
90 if (c == delim || c == '\0')
93 return IN6PTON_COLON_MASK;
99 return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
102 return IN6PTON_DELIM;
103 return IN6PTON_UNKNOWN;
107 * in4_pton - convert an IPv4 address from literal to binary representation
108 * @src: the start of the IPv4 address string
109 * @srclen: the length of the string, -1 means strlen(src)
110 * @dst: the binary (u8[4] array) representation of the IPv4 address
111 * @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
112 * @end: A pointer to the end of the parsed string will be placed here
114 * Return one on success, return zero when any error occurs
115 * and @end will point to the end of the parsed string.
118 int in4_pton(const char *src, int srclen,
120 int delim, const char **end)
130 srclen = strlen(src);
136 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
137 if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
140 if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
146 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
154 if ((w & 0xffff) > 255) {
164 memcpy(dst, dbuf, sizeof(dbuf));
170 EXPORT_SYMBOL(in4_pton);
173 * in6_pton - convert an IPv6 address from literal to binary representation
174 * @src: the start of the IPv6 address string
175 * @srclen: the length of the string, -1 means strlen(src)
176 * @dst: the binary (u8[16] array) representation of the IPv6 address
177 * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
178 * @end: A pointer to the end of the parsed string will be placed here
180 * Return one on success, return zero when any error occurs
181 * and @end will point to the end of the parsed string.
184 int in6_pton(const char *src, int srclen,
186 int delim, const char **end)
188 const char *s, *tok = NULL;
193 int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
196 memset(dbuf, 0, sizeof(dbuf));
201 srclen = strlen(src);
206 c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
209 if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
210 /* process one 16-bit word */
211 if (!(state & IN6PTON_NULL)) {
212 *d++ = (w >> 8) & 0xff;
216 if (c & IN6PTON_DELIM) {
217 /* We've processed last word */
222 * COLON_2 => XDIGIT|DELIM
223 * COLON_1_2 => COLON_2
225 switch (state & IN6PTON_COLON_MASK) {
226 case IN6PTON_COLON_2:
228 state = IN6PTON_XDIGIT | IN6PTON_DELIM;
229 if (dc - dbuf >= sizeof(dbuf))
230 state |= IN6PTON_NULL;
232 case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
233 state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
235 case IN6PTON_COLON_1:
236 state = IN6PTON_XDIGIT;
238 case IN6PTON_COLON_1_2:
239 state = IN6PTON_COLON_2;
248 if (c & IN6PTON_DOT) {
249 ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
257 w = (w << 4) | (0xff & c);
258 state = IN6PTON_COLON_1 | IN6PTON_DELIM;
260 state |= IN6PTON_XDIGIT;
262 if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
263 state |= IN6PTON_COLON_1_2;
264 state &= ~IN6PTON_DELIM;
266 if (d + 2 >= dbuf + sizeof(dbuf)) {
267 state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
270 if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
271 d + 4 == dbuf + sizeof(dbuf)) {
272 state |= IN6PTON_DOT;
274 if (d >= dbuf + sizeof(dbuf)) {
275 state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
286 while (i >= dc - dbuf)
291 memcpy(dst, dbuf, sizeof(dbuf));
299 EXPORT_SYMBOL(in6_pton);
301 static int inet4_pton(const char *src, u16 port_num,
302 struct sockaddr_storage *addr)
304 struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
305 size_t srclen = strlen(src);
307 if (srclen > INET_ADDRSTRLEN)
310 if (in4_pton(src, srclen, (u8 *)&addr4->sin_addr.s_addr,
314 addr4->sin_family = AF_INET;
315 addr4->sin_port = htons(port_num);
320 static int inet6_pton(struct net *net, const char *src, u16 port_num,
321 struct sockaddr_storage *addr)
323 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
324 const char *scope_delim;
325 size_t srclen = strlen(src);
327 if (srclen > INET6_ADDRSTRLEN)
330 if (in6_pton(src, srclen, (u8 *)&addr6->sin6_addr.s6_addr,
331 '%', &scope_delim) == 0)
334 if (ipv6_addr_type(&addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL &&
335 src + srclen != scope_delim && *scope_delim == '%') {
336 struct net_device *dev;
338 size_t scope_len = min_t(size_t, sizeof(scope_id) - 1,
339 src + srclen - scope_delim - 1);
341 memcpy(scope_id, scope_delim + 1, scope_len);
342 scope_id[scope_len] = '\0';
344 dev = dev_get_by_name(net, scope_id);
346 addr6->sin6_scope_id = dev->ifindex;
348 } else if (kstrtouint(scope_id, 0, &addr6->sin6_scope_id)) {
353 addr6->sin6_family = AF_INET6;
354 addr6->sin6_port = htons(port_num);
360 * inet_pton_with_scope - convert an IPv4/IPv6 and port to socket address
361 * @net: net namespace (used for scope handling)
362 * @af: address family, AF_INET, AF_INET6 or AF_UNSPEC for either
363 * @src: the start of the address string
364 * @port: the start of the port string (or NULL for none)
365 * @addr: output socket address
367 * Return zero on success, return errno when any error occurs.
369 int inet_pton_with_scope(struct net *net, __kernel_sa_family_t af,
370 const char *src, const char *port, struct sockaddr_storage *addr)
376 if (kstrtou16(port, 0, &port_num))
384 ret = inet4_pton(src, port_num, addr);
387 ret = inet6_pton(net, src, port_num, addr);
390 ret = inet4_pton(src, port_num, addr);
392 ret = inet6_pton(net, src, port_num, addr);
395 pr_err("unexpected address family %d\n", af);
400 EXPORT_SYMBOL(inet_pton_with_scope);
402 bool inet_addr_is_any(struct sockaddr *addr)
404 if (addr->sa_family == AF_INET6) {
405 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr;
406 const struct sockaddr_in6 in6_any =
407 { .sin6_addr = IN6ADDR_ANY_INIT };
409 if (!memcmp(in6->sin6_addr.s6_addr,
410 in6_any.sin6_addr.s6_addr, 16))
412 } else if (addr->sa_family == AF_INET) {
413 struct sockaddr_in *in = (struct sockaddr_in *)addr;
415 if (in->sin_addr.s_addr == htonl(INADDR_ANY))
418 pr_warn("unexpected address family %u\n", addr->sa_family);
423 EXPORT_SYMBOL(inet_addr_is_any);
425 void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
426 __be32 from, __be32 to, bool pseudohdr)
428 if (skb->ip_summed != CHECKSUM_PARTIAL) {
429 csum_replace4(sum, from, to);
430 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
431 skb->csum = ~csum_add(csum_sub(~(skb->csum),
432 (__force __wsum)from),
434 } else if (pseudohdr)
435 *sum = ~csum_fold(csum_add(csum_sub(csum_unfold(*sum),
436 (__force __wsum)from),
437 (__force __wsum)to));
439 EXPORT_SYMBOL(inet_proto_csum_replace4);
442 * inet_proto_csum_replace16 - update layer 4 header checksum field
443 * @sum: Layer 4 header checksum field
444 * @skb: sk_buff for the packet
445 * @from: old IPv6 address
446 * @to: new IPv6 address
447 * @pseudohdr: True if layer 4 header checksum includes pseudoheader
449 * Update layer 4 header as per the update in IPv6 src/dst address.
451 * There is no need to update skb->csum in this function, because update in two
452 * fields a.) IPv6 src/dst address and b.) L4 header checksum cancels each other
453 * for skb->csum calculation. Whereas inet_proto_csum_replace4 function needs to
454 * update skb->csum, because update in 3 fields a.) IPv4 src/dst address,
455 * b.) IPv4 Header checksum and c.) L4 header checksum results in same diff as
456 * L4 Header checksum for skb->csum calculation.
458 void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
459 const __be32 *from, const __be32 *to,
463 ~from[0], ~from[1], ~from[2], ~from[3],
464 to[0], to[1], to[2], to[3],
466 if (skb->ip_summed != CHECKSUM_PARTIAL) {
467 *sum = csum_fold(csum_partial(diff, sizeof(diff),
468 ~csum_unfold(*sum)));
469 } else if (pseudohdr)
470 *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
473 EXPORT_SYMBOL(inet_proto_csum_replace16);
475 void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
476 __wsum diff, bool pseudohdr)
478 if (skb->ip_summed != CHECKSUM_PARTIAL) {
479 csum_replace_by_diff(sum, diff);
480 if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
481 skb->csum = ~csum_sub(diff, skb->csum);
482 } else if (pseudohdr) {
483 *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
486 EXPORT_SYMBOL(inet_proto_csum_replace_by_diff);