Initial import

1 files changed, 398 insertions, 0 deletions

diff --git a/fs/ntfs/unistr.c b/fs/ntfs/unistr.c
new file mode 100644
index 000000000..005ca4b0f
--- /dev/null
+++ b/fs/ntfs/unistr.c
@@ -0,0 +1,398 @@
+/*
+ * unistr.c - NTFS Unicode string handling. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001-2006 Anton Altaparmakov
+ *
+ * This program/include file 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.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/slab.h>
+
+#include "types.h"
+#include "debug.h"
+#include "ntfs.h"
+
+/*
+ * IMPORTANT
+ * =========
+ *
+ * All these routines assume that the Unicode characters are in little endian
+ * encoding inside the strings!!!
+ */
+
+/*
+ * This is used by the name collation functions to quickly determine what
+ * characters are (in)valid.
+ */
+static const u8 legal_ansi_char_array[0x40] = {
+	0x00, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
+	0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
+
+	0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
+	0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
+
+	0x17, 0x07, 0x18, 0x17, 0x17, 0x17, 0x17, 0x17,
+	0x17, 0x17, 0x18, 0x16, 0x16, 0x17, 0x07, 0x00,
+
+	0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17,
+	0x17, 0x17, 0x04, 0x16, 0x18, 0x16, 0x18, 0x18,
+};
+
+/**
+ * ntfs_are_names_equal - compare two Unicode names for equality
+ * @s1:			name to compare to @s2
+ * @s1_len:		length in Unicode characters of @s1
+ * @s2:			name to compare to @s1
+ * @s2_len:		length in Unicode characters of @s2
+ * @ic:			ignore case bool
+ * @upcase:		upcase table (only if @ic == IGNORE_CASE)
+ * @upcase_size:	length in Unicode characters of @upcase (if present)
+ *
+ * Compare the names @s1 and @s2 and return 'true' (1) if the names are
+ * identical, or 'false' (0) if they are not identical. If @ic is IGNORE_CASE,
+ * the @upcase table is used to performa a case insensitive comparison.
+ */
+bool ntfs_are_names_equal(const ntfschar *s1, size_t s1_len,
+		const ntfschar *s2, size_t s2_len, const IGNORE_CASE_BOOL ic,
+		const ntfschar *upcase, const u32 upcase_size)
+{
+	if (s1_len != s2_len)
+		return false;
+	if (ic == CASE_SENSITIVE)
+		return !ntfs_ucsncmp(s1, s2, s1_len);
+	return !ntfs_ucsncasecmp(s1, s2, s1_len, upcase, upcase_size);
+}
+
+/**
+ * ntfs_collate_names - collate two Unicode names
+ * @name1:	first Unicode name to compare
+ * @name2:	second Unicode name to compare
+ * @err_val:	if @name1 contains an invalid character return this value
+ * @ic:		either CASE_SENSITIVE or IGNORE_CASE
+ * @upcase:	upcase table (ignored if @ic is CASE_SENSITIVE)
+ * @upcase_len:	upcase table size (ignored if @ic is CASE_SENSITIVE)
+ *
+ * ntfs_collate_names collates two Unicode names and returns:
+ *
+ *  -1 if the first name collates before the second one,
+ *   0 if the names match,
+ *   1 if the second name collates before the first one, or
+ * @err_val if an invalid character is found in @name1 during the comparison.
+ *
+ * The following characters are considered invalid: '"', '*', '<', '>' and '?'.
+ */
+int ntfs_collate_names(const ntfschar *name1, const u32 name1_len,
+		const ntfschar *name2, const u32 name2_len,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const ntfschar *upcase, const u32 upcase_len)
+{
+	u32 cnt, min_len;
+	u16 c1, c2;
+
+	min_len = name1_len;
+	if (name1_len > name2_len)
+		min_len = name2_len;
+	for (cnt = 0; cnt < min_len; ++cnt) {
+		c1 = le16_to_cpu(*name1++);
+		c2 = le16_to_cpu(*name2++);
+		if (ic) {
+			if (c1 < upcase_len)
+				c1 = le16_to_cpu(upcase[c1]);
+			if (c2 < upcase_len)
+				c2 = le16_to_cpu(upcase[c2]);
+		}
+		if (c1 < 64 && legal_ansi_char_array[c1] & 8)
+			return err_val;
+		if (c1 < c2)
+			return -1;
+		if (c1 > c2)
+			return 1;
+	}
+	if (name1_len < name2_len)
+		return -1;
+	if (name1_len == name2_len)
+		return 0;
+	/* name1_len > name2_len */
+	c1 = le16_to_cpu(*name1);
+	if (c1 < 64 && legal_ansi_char_array[c1] & 8)
+		return err_val;
+	return 1;
+}
+
+/**
+ * ntfs_ucsncmp - compare two little endian Unicode strings
+ * @s1:		first string
+ * @s2:		second string
+ * @n:		maximum unicode characters to compare
+ *
+ * Compare the first @n characters of the Unicode strings @s1 and @s2,
+ * The strings in little endian format and appropriate le16_to_cpu()
+ * conversion is performed on non-little endian machines.
+ *
+ * The function returns an integer less than, equal to, or greater than zero
+ * if @s1 (or the first @n Unicode characters thereof) is found, respectively,
+ * to be less than, to match, or be greater than @s2.
+ */
+int ntfs_ucsncmp(const ntfschar *s1, const ntfschar *s2, size_t n)
+{
+	u16 c1, c2;
+	size_t i;
+
+	for (i = 0; i < n; ++i) {
+		c1 = le16_to_cpu(s1[i]);
+		c2 = le16_to_cpu(s2[i]);
+		if (c1 < c2)
+			return -1;
+		if (c1 > c2)
+			return 1;
+		if (!c1)
+			break;
+	}
+	return 0;
+}
+
+/**
+ * ntfs_ucsncasecmp - compare two little endian Unicode strings, ignoring case
+ * @s1:			first string
+ * @s2:			second string
+ * @n:			maximum unicode characters to compare
+ * @upcase:		upcase table
+ * @upcase_size:	upcase table size in Unicode characters
+ *
+ * Compare the first @n characters of the Unicode strings @s1 and @s2,
+ * ignoring case. The strings in little endian format and appropriate
+ * le16_to_cpu() conversion is performed on non-little endian machines.
+ *
+ * Each character is uppercased using the @upcase table before the comparison.
+ *
+ * The function returns an integer less than, equal to, or greater than zero
+ * if @s1 (or the first @n Unicode characters thereof) is found, respectively,
+ * to be less than, to match, or be greater than @s2.
+ */
+int ntfs_ucsncasecmp(const ntfschar *s1, const ntfschar *s2, size_t n,
+		const ntfschar *upcase, const u32 upcase_size)
+{
+	size_t i;
+	u16 c1, c2;
+
+	for (i = 0; i < n; ++i) {
+		if ((c1 = le16_to_cpu(s1[i])) < upcase_size)
+			c1 = le16_to_cpu(upcase[c1]);
+		if ((c2 = le16_to_cpu(s2[i])) < upcase_size)
+			c2 = le16_to_cpu(upcase[c2]);
+		if (c1 < c2)
+			return -1;
+		if (c1 > c2)
+			return 1;
+		if (!c1)
+			break;
+	}
+	return 0;
+}
+
+void ntfs_upcase_name(ntfschar *name, u32 name_len, const ntfschar *upcase,
+		const u32 upcase_len)
+{
+	u32 i;
+	u16 u;
+
+	for (i = 0; i < name_len; i++)
+		if ((u = le16_to_cpu(name[i])) < upcase_len)
+			name[i] = upcase[u];
+}
+
+void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr,
+		const ntfschar *upcase, const u32 upcase_len)
+{
+	ntfs_upcase_name((ntfschar*)&file_name_attr->file_name,
+			file_name_attr->file_name_length, upcase, upcase_len);
+}
+
+int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1,
+		FILE_NAME_ATTR *file_name_attr2,
+		const int err_val, const IGNORE_CASE_BOOL ic,
+		const ntfschar *upcase, const u32 upcase_len)
+{
+	return ntfs_collate_names((ntfschar*)&file_name_attr1->file_name,
+			file_name_attr1->file_name_length,
+			(ntfschar*)&file_name_attr2->file_name,
+			file_name_attr2->file_name_length,
+			err_val, ic, upcase, upcase_len);
+}
+
+/**
+ * ntfs_nlstoucs - convert NLS string to little endian Unicode string
+ * @vol:	ntfs volume which we are working with
+ * @ins:	input NLS string buffer
+ * @ins_len:	length of input string in bytes
+ * @outs:	on return contains the allocated output Unicode string buffer
+ *
+ * Convert the input string @ins, which is in whatever format the loaded NLS
+ * map dictates, into a little endian, 2-byte Unicode string.
+ *
+ * This function allocates the string and the caller is responsible for
+ * calling kmem_cache_free(ntfs_name_cache, *@outs); when finished with it.
+ *
+ * On success the function returns the number of Unicode characters written to
+ * the output string *@outs (>= 0), not counting the terminating Unicode NULL
+ * character. *@outs is set to the allocated output string buffer.
+ *
+ * On error, a negative number corresponding to the error code is returned. In
+ * that case the output string is not allocated. Both *@outs and *@outs_len
+ * are then undefined.
+ *
+ * This might look a bit odd due to fast path optimization...
+ */
+int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins,
+		const int ins_len, ntfschar **outs)
+{
+	struct nls_table *nls = vol->nls_map;
+	ntfschar *ucs;
+	wchar_t wc;
+	int i, o, wc_len;
+
+	/* We do not trust outside sources. */
+	if (likely(ins)) {
+		ucs = kmem_cache_alloc(ntfs_name_cache, GFP_NOFS);
+		if (likely(ucs)) {
+			for (i = o = 0; i < ins_len; i += wc_len) {
+				wc_len = nls->char2uni(ins + i, ins_len - i,
+						&wc);
+				if (likely(wc_len >= 0 &&
+						o < NTFS_MAX_NAME_LEN)) {
+					if (likely(wc)) {
+						ucs[o++] = cpu_to_le16(wc);
+						continue;
+					} /* else if (!wc) */
+					break;
+				} /* else if (wc_len < 0 ||
+						o >= NTFS_MAX_NAME_LEN) */
+				goto name_err;
+			}
+			ucs[o] = 0;
+			*outs = ucs;
+			return o;
+		} /* else if (!ucs) */
+		ntfs_error(vol->sb, "Failed to allocate buffer for converted "
+				"name from ntfs_name_cache.");
+		return -ENOMEM;
+	} /* else if (!ins) */
+	ntfs_error(vol->sb, "Received NULL pointer.");
+	return -EINVAL;
+name_err:
+	kmem_cache_free(ntfs_name_cache, ucs);
+	if (wc_len < 0) {
+		ntfs_error(vol->sb, "Name using character set %s contains "
+				"characters that cannot be converted to "
+				"Unicode.", nls->charset);
+		i = -EILSEQ;
+	} else /* if (o >= NTFS_MAX_NAME_LEN) */ {
+		ntfs_error(vol->sb, "Name is too long (maximum length for a "
+				"name on NTFS is %d Unicode characters.",
+				NTFS_MAX_NAME_LEN);
+		i = -ENAMETOOLONG;
+	}
+	return i;
+}
+
+/**
+ * ntfs_ucstonls - convert little endian Unicode string to NLS string
+ * @vol:	ntfs volume which we are working with
+ * @ins:	input Unicode string buffer
+ * @ins_len:	length of input string in Unicode characters
+ * @outs:	on return contains the (allocated) output NLS string buffer
+ * @outs_len:	length of output string buffer in bytes
+ *
+ * Convert the input little endian, 2-byte Unicode string @ins, of length
+ * @ins_len into the string format dictated by the loaded NLS.
+ *
+ * If *@outs is NULL, this function allocates the string and the caller is
+ * responsible for calling kfree(*@outs); when finished with it. In this case
+ * @outs_len is ignored and can be 0.
+ *
+ * On success the function returns the number of bytes written to the output
+ * string *@outs (>= 0), not counting the terminating NULL byte. If the output
+ * string buffer was allocated, *@outs is set to it.
+ *
+ * On error, a negative number corresponding to the error code is returned. In
+ * that case the output string is not allocated. The contents of *@outs are
+ * then undefined.
+ *
+ * This might look a bit odd due to fast path optimization...
+ */
+int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins,
+		const int ins_len, unsigned char **outs, int outs_len)
+{
+	struct nls_table *nls = vol->nls_map;
+	unsigned char *ns;
+	int i, o, ns_len, wc;
+
+	/* We don't trust outside sources. */
+	if (ins) {
+		ns = *outs;
+		ns_len = outs_len;
+		if (ns && !ns_len) {
+			wc = -ENAMETOOLONG;
+			goto conversion_err;
+		}
+		if (!ns) {
+			ns_len = ins_len * NLS_MAX_CHARSET_SIZE;
+			ns = kmalloc(ns_len + 1, GFP_NOFS);
+			if (!ns)
+				goto mem_err_out;
+		}
+		for (i = o = 0; i < ins_len; i++) {
+retry:			wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o,
+					ns_len - o);
+			if (wc > 0) {
+				o += wc;
+				continue;
+			} else if (!wc)
+				break;
+			else if (wc == -ENAMETOOLONG && ns != *outs) {
+				unsigned char *tc;
+				/* Grow in multiples of 64 bytes. */
+				tc = kmalloc((ns_len + 64) &
+						~63, GFP_NOFS);
+				if (tc) {
+					memcpy(tc, ns, ns_len);
+					ns_len = ((ns_len + 64) & ~63) - 1;
+					kfree(ns);
+					ns = tc;
+					goto retry;
+				} /* No memory so goto conversion_error; */
+			} /* wc < 0, real error. */
+			goto conversion_err;
+		}
+		ns[o] = 0;
+		*outs = ns;
+		return o;
+	} /* else (!ins) */
+	ntfs_error(vol->sb, "Received NULL pointer.");
+	return -EINVAL;
+conversion_err:
+	ntfs_error(vol->sb, "Unicode name contains characters that cannot be "
+			"converted to character set %s.  You might want to "
+			"try to use the mount option nls=utf8.", nls->charset);
+	if (ns != *outs)
+		kfree(ns);
+	if (wc != -ENAMETOOLONG)
+		wc = -EILSEQ;
+	return wc;
+mem_err_out:
+	ntfs_error(vol->sb, "Failed to allocate name!");
+	return -ENOMEM;
+}