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-rw-r--r--fs/cifs/cifs_unicode.c388
1 files changed, 357 insertions, 31 deletions
diff --git a/fs/cifs/cifs_unicode.c b/fs/cifs/cifs_unicode.c
index 7d75272a6b3..15e9505aa35 100644
--- a/fs/cifs/cifs_unicode.c
+++ b/fs/cifs/cifs_unicode.c
@@ -1,7 +1,7 @@
/*
* fs/cifs/cifs_unicode.c
*
- * Copyright (c) International Business Machines Corp., 2000,2005
+ * Copyright (c) International Business Machines Corp., 2000,2009
* Modified by Steve French (sfrench@us.ibm.com)
*
* This program is free software; you can redistribute it and/or modify
@@ -19,6 +19,7 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
+#include <linux/slab.h>
#include "cifs_unicode.h"
#include "cifs_uniupr.h"
#include "cifspdu.h"
@@ -26,65 +27,390 @@
#include "cifs_debug.h"
/*
- * NAME: cifs_strfromUCS()
- *
- * FUNCTION: Convert little-endian unicode string to character string
+ * cifs_utf16_bytes - how long will a string be after conversion?
+ * @utf16 - pointer to input string
+ * @maxbytes - don't go past this many bytes of input string
+ * @codepage - destination codepage
*
+ * Walk a utf16le string and return the number of bytes that the string will
+ * be after being converted to the given charset, not including any null
+ * termination required. Don't walk past maxbytes in the source buffer.
*/
int
-cifs_strfromUCS_le(char *to, const __le16 *from,
- int len, const struct nls_table *codepage)
+cifs_utf16_bytes(const __le16 *from, int maxbytes,
+ const struct nls_table *codepage)
{
int i;
- int outlen = 0;
+ int charlen, outlen = 0;
+ int maxwords = maxbytes / 2;
+ char tmp[NLS_MAX_CHARSET_SIZE];
+ __u16 ftmp;
+
+ for (i = 0; i < maxwords; i++) {
+ ftmp = get_unaligned_le16(&from[i]);
+ if (ftmp == 0)
+ break;
- for (i = 0; (i < len) && from[i]; i++) {
- int charlen;
- /* 2.4.0 kernel or greater */
- charlen =
- codepage->uni2char(le16_to_cpu(from[i]), &to[outlen],
- NLS_MAX_CHARSET_SIZE);
- if (charlen > 0) {
+ charlen = codepage->uni2char(ftmp, tmp, NLS_MAX_CHARSET_SIZE);
+ if (charlen > 0)
outlen += charlen;
- } else {
- to[outlen++] = '?';
+ else
+ outlen++;
+ }
+
+ return outlen;
+}
+
+/*
+ * cifs_mapchar - convert a host-endian char to proper char in codepage
+ * @target - where converted character should be copied
+ * @src_char - 2 byte host-endian source character
+ * @cp - codepage to which character should be converted
+ * @mapchar - should character be mapped according to mapchars mount option?
+ *
+ * This function handles the conversion of a single character. It is the
+ * responsibility of the caller to ensure that the target buffer is large
+ * enough to hold the result of the conversion (at least NLS_MAX_CHARSET_SIZE).
+ */
+static int
+cifs_mapchar(char *target, const __u16 src_char, const struct nls_table *cp,
+ bool mapchar)
+{
+ int len = 1;
+
+ if (!mapchar)
+ goto cp_convert;
+
+ /*
+ * BB: Cannot handle remapping UNI_SLASH until all the calls to
+ * build_path_from_dentry are modified, as they use slash as
+ * separator.
+ */
+ switch (src_char) {
+ case UNI_COLON:
+ *target = ':';
+ break;
+ case UNI_ASTERISK:
+ *target = '*';
+ break;
+ case UNI_QUESTION:
+ *target = '?';
+ break;
+ case UNI_PIPE:
+ *target = '|';
+ break;
+ case UNI_GRTRTHAN:
+ *target = '>';
+ break;
+ case UNI_LESSTHAN:
+ *target = '<';
+ break;
+ default:
+ goto cp_convert;
+ }
+
+out:
+ return len;
+
+cp_convert:
+ len = cp->uni2char(src_char, target, NLS_MAX_CHARSET_SIZE);
+ if (len <= 0) {
+ *target = '?';
+ len = 1;
+ }
+ goto out;
+}
+
+/*
+ * cifs_from_utf16 - convert utf16le string to local charset
+ * @to - destination buffer
+ * @from - source buffer
+ * @tolen - destination buffer size (in bytes)
+ * @fromlen - source buffer size (in bytes)
+ * @codepage - codepage to which characters should be converted
+ * @mapchar - should characters be remapped according to the mapchars option?
+ *
+ * Convert a little-endian utf16le string (as sent by the server) to a string
+ * in the provided codepage. The tolen and fromlen parameters are to ensure
+ * that the code doesn't walk off of the end of the buffer (which is always
+ * a danger if the alignment of the source buffer is off). The destination
+ * string is always properly null terminated and fits in the destination
+ * buffer. Returns the length of the destination string in bytes (including
+ * null terminator).
+ *
+ * Note that some windows versions actually send multiword UTF-16 characters
+ * instead of straight UTF16-2. The linux nls routines however aren't able to
+ * deal with those characters properly. In the event that we get some of
+ * those characters, they won't be translated properly.
+ */
+int
+cifs_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
+ const struct nls_table *codepage, bool mapchar)
+{
+ int i, charlen, safelen;
+ int outlen = 0;
+ int nullsize = nls_nullsize(codepage);
+ int fromwords = fromlen / 2;
+ char tmp[NLS_MAX_CHARSET_SIZE];
+ __u16 ftmp;
+
+ /*
+ * because the chars can be of varying widths, we need to take care
+ * not to overflow the destination buffer when we get close to the
+ * end of it. Until we get to this offset, we don't need to check
+ * for overflow however.
+ */
+ safelen = tolen - (NLS_MAX_CHARSET_SIZE + nullsize);
+
+ for (i = 0; i < fromwords; i++) {
+ ftmp = get_unaligned_le16(&from[i]);
+ if (ftmp == 0)
+ break;
+
+ /*
+ * check to see if converting this character might make the
+ * conversion bleed into the null terminator
+ */
+ if (outlen >= safelen) {
+ charlen = cifs_mapchar(tmp, ftmp, codepage, mapchar);
+ if ((outlen + charlen) > (tolen - nullsize))
+ break;
}
+
+ /* put converted char into 'to' buffer */
+ charlen = cifs_mapchar(&to[outlen], ftmp, codepage, mapchar);
+ outlen += charlen;
}
- to[outlen] = 0;
+
+ /* properly null-terminate string */
+ for (i = 0; i < nullsize; i++)
+ to[outlen++] = 0;
+
return outlen;
}
/*
- * NAME: cifs_strtoUCS()
+ * NAME: cifs_strtoUTF16()
*
* FUNCTION: Convert character string to unicode string
*
*/
int
-cifs_strtoUCS(__le16 *to, const char *from, int len,
+cifs_strtoUTF16(__le16 *to, const char *from, int len,
const struct nls_table *codepage)
{
int charlen;
int i;
- wchar_t *wchar_to = (wchar_t *)to; /* needed to quiet sparse */
+ wchar_t wchar_to; /* needed to quiet sparse */
- for (i = 0; len && *from; i++, from += charlen, len -= charlen) {
+ /* special case for utf8 to handle no plane0 chars */
+ if (!strcmp(codepage->charset, "utf8")) {
+ /*
+ * convert utf8 -> utf16, we assume we have enough space
+ * as caller should have assumed conversion does not overflow
+ * in destination len is length in wchar_t units (16bits)
+ */
+ i = utf8s_to_utf16s(from, len, UTF16_LITTLE_ENDIAN,
+ (wchar_t *) to, len);
+
+ /* if success terminate and exit */
+ if (i >= 0)
+ goto success;
+ /*
+ * if fails fall back to UCS encoding as this
+ * function should not return negative values
+ * currently can fail only if source contains
+ * invalid encoded characters
+ */
+ }
- /* works for 2.4.0 kernel or later */
- charlen = codepage->char2uni(from, len, &wchar_to[i]);
+ for (i = 0; len && *from; i++, from += charlen, len -= charlen) {
+ charlen = codepage->char2uni(from, len, &wchar_to);
if (charlen < 1) {
- cERROR(1,
- ("strtoUCS: char2uni of %d returned %d",
- (int)*from, charlen));
+ cifs_dbg(VFS, "strtoUTF16: char2uni of 0x%x returned %d\n",
+ *from, charlen);
/* A question mark */
- to[i] = cpu_to_le16(0x003f);
+ wchar_to = 0x003f;
charlen = 1;
- } else
- to[i] = cpu_to_le16(wchar_to[i]);
-
+ }
+ put_unaligned_le16(wchar_to, &to[i]);
}
- to[i] = 0;
+success:
+ put_unaligned_le16(0, &to[i]);
return i;
}
+/*
+ * cifs_strndup_from_utf16 - copy a string from wire format to the local
+ * codepage
+ * @src - source string
+ * @maxlen - don't walk past this many bytes in the source string
+ * @is_unicode - is this a unicode string?
+ * @codepage - destination codepage
+ *
+ * Take a string given by the server, convert it to the local codepage and
+ * put it in a new buffer. Returns a pointer to the new string or NULL on
+ * error.
+ */
+char *
+cifs_strndup_from_utf16(const char *src, const int maxlen,
+ const bool is_unicode, const struct nls_table *codepage)
+{
+ int len;
+ char *dst;
+
+ if (is_unicode) {
+ len = cifs_utf16_bytes((__le16 *) src, maxlen, codepage);
+ len += nls_nullsize(codepage);
+ dst = kmalloc(len, GFP_KERNEL);
+ if (!dst)
+ return NULL;
+ cifs_from_utf16(dst, (__le16 *) src, len, maxlen, codepage,
+ false);
+ } else {
+ len = strnlen(src, maxlen);
+ len++;
+ dst = kmalloc(len, GFP_KERNEL);
+ if (!dst)
+ return NULL;
+ strlcpy(dst, src, len);
+ }
+
+ return dst;
+}
+
+/*
+ * Convert 16 bit Unicode pathname to wire format from string in current code
+ * page. Conversion may involve remapping up the six characters that are
+ * only legal in POSIX-like OS (if they are present in the string). Path
+ * names are little endian 16 bit Unicode on the wire
+ */
+int
+cifsConvertToUTF16(__le16 *target, const char *source, int srclen,
+ const struct nls_table *cp, int mapChars)
+{
+ int i, charlen;
+ int j = 0;
+ char src_char;
+ __le16 dst_char;
+ wchar_t tmp;
+
+ if (!mapChars)
+ return cifs_strtoUTF16(target, source, PATH_MAX, cp);
+
+ for (i = 0; i < srclen; j++) {
+ src_char = source[i];
+ charlen = 1;
+ switch (src_char) {
+ case 0:
+ goto ctoUTF16_out;
+ case ':':
+ dst_char = cpu_to_le16(UNI_COLON);
+ break;
+ case '*':
+ dst_char = cpu_to_le16(UNI_ASTERISK);
+ break;
+ case '?':
+ dst_char = cpu_to_le16(UNI_QUESTION);
+ break;
+ case '<':
+ dst_char = cpu_to_le16(UNI_LESSTHAN);
+ break;
+ case '>':
+ dst_char = cpu_to_le16(UNI_GRTRTHAN);
+ break;
+ case '|':
+ dst_char = cpu_to_le16(UNI_PIPE);
+ break;
+ /*
+ * FIXME: We can not handle remapping backslash (UNI_SLASH)
+ * until all the calls to build_path_from_dentry are modified,
+ * as they use backslash as separator.
+ */
+ default:
+ charlen = cp->char2uni(source + i, srclen - i, &tmp);
+ dst_char = cpu_to_le16(tmp);
+
+ /*
+ * if no match, use question mark, which at least in
+ * some cases serves as wild card
+ */
+ if (charlen < 1) {
+ dst_char = cpu_to_le16(0x003f);
+ charlen = 1;
+ }
+ }
+ /*
+ * character may take more than one byte in the source string,
+ * but will take exactly two bytes in the target string
+ */
+ i += charlen;
+ put_unaligned(dst_char, &target[j]);
+ }
+
+ctoUTF16_out:
+ put_unaligned(0, &target[j]); /* Null terminate target unicode string */
+ return j;
+}
+
+#ifdef CONFIG_CIFS_SMB2
+/*
+ * cifs_local_to_utf16_bytes - how long will a string be after conversion?
+ * @from - pointer to input string
+ * @maxbytes - don't go past this many bytes of input string
+ * @codepage - source codepage
+ *
+ * Walk a string and return the number of bytes that the string will
+ * be after being converted to the given charset, not including any null
+ * termination required. Don't walk past maxbytes in the source buffer.
+ */
+
+static int
+cifs_local_to_utf16_bytes(const char *from, int len,
+ const struct nls_table *codepage)
+{
+ int charlen;
+ int i;
+ wchar_t wchar_to;
+
+ for (i = 0; len && *from; i++, from += charlen, len -= charlen) {
+ charlen = codepage->char2uni(from, len, &wchar_to);
+ /* Failed conversion defaults to a question mark */
+ if (charlen < 1)
+ charlen = 1;
+ }
+ return 2 * i; /* UTF16 characters are two bytes */
+}
+
+/*
+ * cifs_strndup_to_utf16 - copy a string to wire format from the local codepage
+ * @src - source string
+ * @maxlen - don't walk past this many bytes in the source string
+ * @utf16_len - the length of the allocated string in bytes (including null)
+ * @cp - source codepage
+ * @remap - map special chars
+ *
+ * Take a string convert it from the local codepage to UTF16 and
+ * put it in a new buffer. Returns a pointer to the new string or NULL on
+ * error.
+ */
+__le16 *
+cifs_strndup_to_utf16(const char *src, const int maxlen, int *utf16_len,
+ const struct nls_table *cp, int remap)
+{
+ int len;
+ __le16 *dst;
+
+ len = cifs_local_to_utf16_bytes(src, maxlen, cp);
+ len += 2; /* NULL */
+ dst = kmalloc(len, GFP_KERNEL);
+ if (!dst) {
+ *utf16_len = 0;
+ return NULL;
+ }
+ cifsConvertToUTF16(dst, src, strlen(src), cp, remap);
+ *utf16_len = len;
+ return dst;
+}
+#endif /* CONFIG_CIFS_SMB2 */
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