Initial import

1 files changed, 384 insertions, 0 deletions

diff --git a/net/core/utils.c b/net/core/utils.c
new file mode 100644
index 000000000..7b803884c
--- /dev/null
+++ b/net/core/utils.c
@@ -0,0 +1,384 @@
+/*
+ *	Generic address resultion entity
+ *
+ *	Authors:
+ *	net_random Alan Cox
+ *	net_ratelimit Andi Kleen
+ *	in{4,6}_pton YOSHIFUJI Hideaki, Copyright (C)2006 USAGI/WIDE Project
+ *
+ *	Created by Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ *
+ *	This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/inet.h>
+#include <linux/mm.h>
+#include <linux/net.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/percpu.h>
+#include <linux/init.h>
+#include <linux/ratelimit.h>
+
+#include <net/sock.h>
+#include <net/net_ratelimit.h>
+
+#include <asm/byteorder.h>
+#include <asm/uaccess.h>
+
+DEFINE_RATELIMIT_STATE(net_ratelimit_state, 5 * HZ, 10);
+/*
+ * All net warning printk()s should be guarded by this function.
+ */
+int net_ratelimit(void)
+{
+	return __ratelimit(&net_ratelimit_state);
+}
+EXPORT_SYMBOL(net_ratelimit);
+
+/*
+ * Convert an ASCII string to binary IP.
+ * This is outside of net/ipv4/ because various code that uses IP addresses
+ * is otherwise not dependent on the TCP/IP stack.
+ */
+
+__be32 in_aton(const char *str)
+{
+	unsigned long l;
+	unsigned int val;
+	int i;
+
+	l = 0;
+	for (i = 0; i < 4; i++)	{
+		l <<= 8;
+		if (*str != '\0') {
+			val = 0;
+			while (*str != '\0' && *str != '.' && *str != '\n') {
+				val *= 10;
+				val += *str - '0';
+				str++;
+			}
+			l |= val;
+			if (*str != '\0')
+				str++;
+		}
+	}
+	return htonl(l);
+}
+EXPORT_SYMBOL(in_aton);
+
+#define IN6PTON_XDIGIT		0x00010000
+#define IN6PTON_DIGIT		0x00020000
+#define IN6PTON_COLON_MASK	0x00700000
+#define IN6PTON_COLON_1		0x00100000	/* single : requested */
+#define IN6PTON_COLON_2		0x00200000	/* second : requested */
+#define IN6PTON_COLON_1_2	0x00400000	/* :: requested */
+#define IN6PTON_DOT		0x00800000	/* . */
+#define IN6PTON_DELIM		0x10000000
+#define IN6PTON_NULL		0x20000000	/* first/tail */
+#define IN6PTON_UNKNOWN		0x40000000
+
+static inline int xdigit2bin(char c, int delim)
+{
+	int val;
+
+	if (c == delim || c == '\0')
+		return IN6PTON_DELIM;
+	if (c == ':')
+		return IN6PTON_COLON_MASK;
+	if (c == '.')
+		return IN6PTON_DOT;
+
+	val = hex_to_bin(c);
+	if (val >= 0)
+		return val | IN6PTON_XDIGIT | (val < 10 ? IN6PTON_DIGIT : 0);
+
+	if (delim == -1)
+		return IN6PTON_DELIM;
+	return IN6PTON_UNKNOWN;
+}
+
+/**
+ * in4_pton - convert an IPv4 address from literal to binary representation
+ * @src: the start of the IPv4 address string
+ * @srclen: the length of the string, -1 means strlen(src)
+ * @dst: the binary (u8[4] array) representation of the IPv4 address
+ * @delim: the delimiter of the IPv4 address in @src, -1 means no delimiter
+ * @end: A pointer to the end of the parsed string will be placed here
+ *
+ * Return one on success, return zero when any error occurs
+ * and @end will point to the end of the parsed string.
+ *
+ */
+int in4_pton(const char *src, int srclen,
+	     u8 *dst,
+	     int delim, const char **end)
+{
+	const char *s;
+	u8 *d;
+	u8 dbuf[4];
+	int ret = 0;
+	int i;
+	int w = 0;
+
+	if (srclen < 0)
+		srclen = strlen(src);
+	s = src;
+	d = dbuf;
+	i = 0;
+	while(1) {
+		int c;
+		c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
+		if (!(c & (IN6PTON_DIGIT | IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK))) {
+			goto out;
+		}
+		if (c & (IN6PTON_DOT | IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
+			if (w == 0)
+				goto out;
+			*d++ = w & 0xff;
+			w = 0;
+			i++;
+			if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
+				if (i != 4)
+					goto out;
+				break;
+			}
+			goto cont;
+		}
+		w = (w * 10) + c;
+		if ((w & 0xffff) > 255) {
+			goto out;
+		}
+cont:
+		if (i >= 4)
+			goto out;
+		s++;
+		srclen--;
+	}
+	ret = 1;
+	memcpy(dst, dbuf, sizeof(dbuf));
+out:
+	if (end)
+		*end = s;
+	return ret;
+}
+EXPORT_SYMBOL(in4_pton);
+
+/**
+ * in6_pton - convert an IPv6 address from literal to binary representation
+ * @src: the start of the IPv6 address string
+ * @srclen: the length of the string, -1 means strlen(src)
+ * @dst: the binary (u8[16] array) representation of the IPv6 address
+ * @delim: the delimiter of the IPv6 address in @src, -1 means no delimiter
+ * @end: A pointer to the end of the parsed string will be placed here
+ *
+ * Return one on success, return zero when any error occurs
+ * and @end will point to the end of the parsed string.
+ *
+ */
+int in6_pton(const char *src, int srclen,
+	     u8 *dst,
+	     int delim, const char **end)
+{
+	const char *s, *tok = NULL;
+	u8 *d, *dc = NULL;
+	u8 dbuf[16];
+	int ret = 0;
+	int i;
+	int state = IN6PTON_COLON_1_2 | IN6PTON_XDIGIT | IN6PTON_NULL;
+	int w = 0;
+
+	memset(dbuf, 0, sizeof(dbuf));
+
+	s = src;
+	d = dbuf;
+	if (srclen < 0)
+		srclen = strlen(src);
+
+	while (1) {
+		int c;
+
+		c = xdigit2bin(srclen > 0 ? *s : '\0', delim);
+		if (!(c & state))
+			goto out;
+		if (c & (IN6PTON_DELIM | IN6PTON_COLON_MASK)) {
+			/* process one 16-bit word */
+			if (!(state & IN6PTON_NULL)) {
+				*d++ = (w >> 8) & 0xff;
+				*d++ = w & 0xff;
+			}
+			w = 0;
+			if (c & IN6PTON_DELIM) {
+				/* We've processed last word */
+				break;
+			}
+			/*
+			 * COLON_1 => XDIGIT
+			 * COLON_2 => XDIGIT|DELIM
+			 * COLON_1_2 => COLON_2
+			 */
+			switch (state & IN6PTON_COLON_MASK) {
+			case IN6PTON_COLON_2:
+				dc = d;
+				state = IN6PTON_XDIGIT | IN6PTON_DELIM;
+				if (dc - dbuf >= sizeof(dbuf))
+					state |= IN6PTON_NULL;
+				break;
+			case IN6PTON_COLON_1|IN6PTON_COLON_1_2:
+				state = IN6PTON_XDIGIT | IN6PTON_COLON_2;
+				break;
+			case IN6PTON_COLON_1:
+				state = IN6PTON_XDIGIT;
+				break;
+			case IN6PTON_COLON_1_2:
+				state = IN6PTON_COLON_2;
+				break;
+			default:
+				state = 0;
+			}
+			tok = s + 1;
+			goto cont;
+		}
+
+		if (c & IN6PTON_DOT) {
+			ret = in4_pton(tok ? tok : s, srclen + (int)(s - tok), d, delim, &s);
+			if (ret > 0) {
+				d += 4;
+				break;
+			}
+			goto out;
+		}
+
+		w = (w << 4) | (0xff & c);
+		state = IN6PTON_COLON_1 | IN6PTON_DELIM;
+		if (!(w & 0xf000)) {
+			state |= IN6PTON_XDIGIT;
+		}
+		if (!dc && d + 2 < dbuf + sizeof(dbuf)) {
+			state |= IN6PTON_COLON_1_2;
+			state &= ~IN6PTON_DELIM;
+		}
+		if (d + 2 >= dbuf + sizeof(dbuf)) {
+			state &= ~(IN6PTON_COLON_1|IN6PTON_COLON_1_2);
+		}
+cont:
+		if ((dc && d + 4 < dbuf + sizeof(dbuf)) ||
+		    d + 4 == dbuf + sizeof(dbuf)) {
+			state |= IN6PTON_DOT;
+		}
+		if (d >= dbuf + sizeof(dbuf)) {
+			state &= ~(IN6PTON_XDIGIT|IN6PTON_COLON_MASK);
+		}
+		s++;
+		srclen--;
+	}
+
+	i = 15; d--;
+
+	if (dc) {
+		while(d >= dc)
+			dst[i--] = *d--;
+		while(i >= dc - dbuf)
+			dst[i--] = 0;
+		while(i >= 0)
+			dst[i--] = *d--;
+	} else
+		memcpy(dst, dbuf, sizeof(dbuf));
+
+	ret = 1;
+out:
+	if (end)
+		*end = s;
+	return ret;
+}
+EXPORT_SYMBOL(in6_pton);
+
+void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
+			      __be32 from, __be32 to, int pseudohdr)
+{
+	if (skb->ip_summed != CHECKSUM_PARTIAL) {
+		*sum = csum_fold(csum_add(csum_sub(~csum_unfold(*sum), from),
+				 to));
+		if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+			skb->csum = ~csum_add(csum_sub(~(skb->csum), from), to);
+	} else if (pseudohdr)
+		*sum = ~csum_fold(csum_add(csum_sub(csum_unfold(*sum), from),
+				  to));
+}
+EXPORT_SYMBOL(inet_proto_csum_replace4);
+
+void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
+			       const __be32 *from, const __be32 *to,
+			       int pseudohdr)
+{
+	__be32 diff[] = {
+		~from[0], ~from[1], ~from[2], ~from[3],
+		to[0], to[1], to[2], to[3],
+	};
+	if (skb->ip_summed != CHECKSUM_PARTIAL) {
+		*sum = csum_fold(csum_partial(diff, sizeof(diff),
+				 ~csum_unfold(*sum)));
+		if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+			skb->csum = ~csum_partial(diff, sizeof(diff),
+						  ~skb->csum);
+	} else if (pseudohdr)
+		*sum = ~csum_fold(csum_partial(diff, sizeof(diff),
+				  csum_unfold(*sum)));
+}
+EXPORT_SYMBOL(inet_proto_csum_replace16);
+
+struct __net_random_once_work {
+	struct work_struct work;
+	struct static_key *key;
+};
+
+static void __net_random_once_deferred(struct work_struct *w)
+{
+	struct __net_random_once_work *work =
+		container_of(w, struct __net_random_once_work, work);
+	BUG_ON(!static_key_enabled(work->key));
+	static_key_slow_dec(work->key);
+	kfree(work);
+}
+
+static void __net_random_once_disable_jump(struct static_key *key)
+{
+	struct __net_random_once_work *w;
+
+	w = kmalloc(sizeof(*w), GFP_ATOMIC);
+	if (!w)
+		return;
+
+	INIT_WORK(&w->work, __net_random_once_deferred);
+	w->key = key;
+	schedule_work(&w->work);
+}
+
+bool __net_get_random_once(void *buf, int nbytes, bool *done,
+			   struct static_key *once_key)
+{
+	static DEFINE_SPINLOCK(lock);
+	unsigned long flags;
+
+	spin_lock_irqsave(&lock, flags);
+	if (*done) {
+		spin_unlock_irqrestore(&lock, flags);
+		return false;
+	}
+
+	get_random_bytes(buf, nbytes);
+	*done = true;
+	spin_unlock_irqrestore(&lock, flags);
+
+	__net_random_once_disable_jump(once_key);
+
+	return true;
+}
+EXPORT_SYMBOL(__net_get_random_once);