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-rw-r--r--net/core/utils.c486
1 files changed, 486 insertions, 0 deletions
diff --git a/net/core/utils.c b/net/core/utils.c
new file mode 100644
index 000000000..938495bc1
--- /dev/null
+++ b/net/core/utils.c
@@ -0,0 +1,486 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+#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 <linux/socket.h>
+
+#include <net/sock.h>
+#include <net/net_ratelimit.h>
+#include <net/ipv6.h>
+
+#include <asm/byteorder.h>
+#include <linux/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 int 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);
+
+static int inet4_pton(const char *src, u16 port_num,
+ struct sockaddr_storage *addr)
+{
+ struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
+ int srclen = strlen(src);
+
+ if (srclen > INET_ADDRSTRLEN)
+ return -EINVAL;
+
+ if (in4_pton(src, srclen, (u8 *)&addr4->sin_addr.s_addr,
+ '\n', NULL) == 0)
+ return -EINVAL;
+
+ addr4->sin_family = AF_INET;
+ addr4->sin_port = htons(port_num);
+
+ return 0;
+}
+
+static int inet6_pton(struct net *net, const char *src, u16 port_num,
+ struct sockaddr_storage *addr)
+{
+ struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
+ const char *scope_delim;
+ int srclen = strlen(src);
+
+ if (srclen > INET6_ADDRSTRLEN)
+ return -EINVAL;
+
+ if (in6_pton(src, srclen, (u8 *)&addr6->sin6_addr.s6_addr,
+ '%', &scope_delim) == 0)
+ return -EINVAL;
+
+ if (ipv6_addr_type(&addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL &&
+ src + srclen != scope_delim && *scope_delim == '%') {
+ struct net_device *dev;
+ char scope_id[16];
+ size_t scope_len = min_t(size_t, sizeof(scope_id) - 1,
+ src + srclen - scope_delim - 1);
+
+ memcpy(scope_id, scope_delim + 1, scope_len);
+ scope_id[scope_len] = '\0';
+
+ dev = dev_get_by_name(net, scope_id);
+ if (dev) {
+ addr6->sin6_scope_id = dev->ifindex;
+ dev_put(dev);
+ } else if (kstrtouint(scope_id, 0, &addr6->sin6_scope_id)) {
+ return -EINVAL;
+ }
+ }
+
+ addr6->sin6_family = AF_INET6;
+ addr6->sin6_port = htons(port_num);
+
+ return 0;
+}
+
+/**
+ * inet_pton_with_scope - convert an IPv4/IPv6 and port to socket address
+ * @net: net namespace (used for scope handling)
+ * @af: address family, AF_INET, AF_INET6 or AF_UNSPEC for either
+ * @src: the start of the address string
+ * @port: the start of the port string (or NULL for none)
+ * @addr: output socket address
+ *
+ * Return zero on success, return errno when any error occurs.
+ */
+int inet_pton_with_scope(struct net *net, __kernel_sa_family_t af,
+ const char *src, const char *port, struct sockaddr_storage *addr)
+{
+ u16 port_num;
+ int ret = -EINVAL;
+
+ if (port) {
+ if (kstrtou16(port, 0, &port_num))
+ return -EINVAL;
+ } else {
+ port_num = 0;
+ }
+
+ switch (af) {
+ case AF_INET:
+ ret = inet4_pton(src, port_num, addr);
+ break;
+ case AF_INET6:
+ ret = inet6_pton(net, src, port_num, addr);
+ break;
+ case AF_UNSPEC:
+ ret = inet4_pton(src, port_num, addr);
+ if (ret)
+ ret = inet6_pton(net, src, port_num, addr);
+ break;
+ default:
+ pr_err("unexpected address family %d\n", af);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(inet_pton_with_scope);
+
+bool inet_addr_is_any(struct sockaddr *addr)
+{
+ if (addr->sa_family == AF_INET6) {
+ struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr;
+ const struct sockaddr_in6 in6_any =
+ { .sin6_addr = IN6ADDR_ANY_INIT };
+
+ if (!memcmp(in6->sin6_addr.s6_addr,
+ in6_any.sin6_addr.s6_addr, 16))
+ return true;
+ } else if (addr->sa_family == AF_INET) {
+ struct sockaddr_in *in = (struct sockaddr_in *)addr;
+
+ if (in->sin_addr.s_addr == htonl(INADDR_ANY))
+ return true;
+ } else {
+ pr_warn("unexpected address family %u\n", addr->sa_family);
+ }
+
+ return false;
+}
+EXPORT_SYMBOL(inet_addr_is_any);
+
+void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb,
+ __be32 from, __be32 to, bool pseudohdr)
+{
+ if (skb->ip_summed != CHECKSUM_PARTIAL) {
+ csum_replace4(sum, from, to);
+ if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+ skb->csum = ~csum_add(csum_sub(~(skb->csum),
+ (__force __wsum)from),
+ (__force __wsum)to);
+ } else if (pseudohdr)
+ *sum = ~csum_fold(csum_add(csum_sub(csum_unfold(*sum),
+ (__force __wsum)from),
+ (__force __wsum)to));
+}
+EXPORT_SYMBOL(inet_proto_csum_replace4);
+
+/**
+ * inet_proto_csum_replace16 - update layer 4 header checksum field
+ * @sum: Layer 4 header checksum field
+ * @skb: sk_buff for the packet
+ * @from: old IPv6 address
+ * @to: new IPv6 address
+ * @pseudohdr: True if layer 4 header checksum includes pseudoheader
+ *
+ * Update layer 4 header as per the update in IPv6 src/dst address.
+ *
+ * There is no need to update skb->csum in this function, because update in two
+ * fields a.) IPv6 src/dst address and b.) L4 header checksum cancels each other
+ * for skb->csum calculation. Whereas inet_proto_csum_replace4 function needs to
+ * update skb->csum, because update in 3 fields a.) IPv4 src/dst address,
+ * b.) IPv4 Header checksum and c.) L4 header checksum results in same diff as
+ * L4 Header checksum for skb->csum calculation.
+ */
+void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb,
+ const __be32 *from, const __be32 *to,
+ bool 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)));
+ } else if (pseudohdr)
+ *sum = ~csum_fold(csum_partial(diff, sizeof(diff),
+ csum_unfold(*sum)));
+}
+EXPORT_SYMBOL(inet_proto_csum_replace16);
+
+void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
+ __wsum diff, bool pseudohdr)
+{
+ if (skb->ip_summed != CHECKSUM_PARTIAL) {
+ csum_replace_by_diff(sum, diff);
+ if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
+ skb->csum = ~csum_sub(diff, skb->csum);
+ } else if (pseudohdr) {
+ *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
+ }
+}
+EXPORT_SYMBOL(inet_proto_csum_replace_by_diff);
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