Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 455 insertions, 0 deletions

diff --git a/fs/smb/server/unicode.c b/fs/smb/server/unicode.c
new file mode 100644
index 000000000..33fc6d45c
--- /dev/null
+++ b/fs/smb/server/unicode.c
@@ -0,0 +1,455 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Some of the source code in this file came from fs/cifs/cifs_unicode.c
+ *
+ *   Copyright (c) International Business Machines  Corp., 2000,2009
+ *   Modified by Steve French (sfrench@us.ibm.com)
+ *   Modified by Namjae Jeon (linkinjeon@kernel.org)
+ */
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+#include "glob.h"
+#include "unicode.h"
+#include "uniupr.h"
+#include "smb_common.h"
+
+/*
+ * cifs_mapchar() - convert a host-endian char to proper char in codepage
+ * @target:	where converted character should be copied
+ * @from:	host-endian source string
+ * @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).
+ *
+ * Return:	string length after conversion
+ */
+static int
+cifs_mapchar(char *target, const __u16 *from, const struct nls_table *cp,
+	     bool mapchar)
+{
+	int len = 1;
+	__u16 src_char;
+
+	src_char = *from;
+
+	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)
+		goto surrogate_pair;
+
+	goto out;
+
+surrogate_pair:
+	/* convert SURROGATE_PAIR and IVS */
+	if (strcmp(cp->charset, "utf8"))
+		goto unknown;
+	len = utf16s_to_utf8s(from, 3, UTF16_LITTLE_ENDIAN, target, 6);
+	if (len <= 0)
+		goto unknown;
+	return len;
+
+unknown:
+	*target = '?';
+	len = 1;
+	goto out;
+}
+
+/*
+ * smb_utf16_bytes() - compute converted string length
+ * @from:	pointer to input string
+ * @maxbytes:	input string length
+ * @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.
+ *
+ * Return:	string length after conversion
+ */
+static int smb_utf16_bytes(const __le16 *from, int maxbytes,
+			   const struct nls_table *codepage)
+{
+	int i, j;
+	int charlen, outlen = 0;
+	int maxwords = maxbytes / 2;
+	char tmp[NLS_MAX_CHARSET_SIZE];
+	__u16 ftmp[3];
+
+	for (i = 0; i < maxwords; i++) {
+		ftmp[0] = get_unaligned_le16(&from[i]);
+		if (ftmp[0] == 0)
+			break;
+		for (j = 1; j <= 2; j++) {
+			if (i + j < maxwords)
+				ftmp[j] = get_unaligned_le16(&from[i + j]);
+			else
+				ftmp[j] = 0;
+		}
+
+		charlen = cifs_mapchar(tmp, ftmp, codepage, 0);
+		if (charlen > 0)
+			outlen += charlen;
+		else
+			outlen++;
+	}
+
+	return outlen;
+}
+
+/*
+ * smb_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.
+ *
+ * Return:	string length after conversion
+ */
+static int smb_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
+			  const struct nls_table *codepage, bool mapchar)
+{
+	int i, j, charlen, safelen;
+	int outlen = 0;
+	int nullsize = nls_nullsize(codepage);
+	int fromwords = fromlen / 2;
+	char tmp[NLS_MAX_CHARSET_SIZE];
+	__u16 ftmp[3];	/* ftmp[3] = 3array x 2bytes = 6bytes UTF-16 */
+
+	/*
+	 * 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[0] = get_unaligned_le16(&from[i]);
+		if (ftmp[0] == 0)
+			break;
+		for (j = 1; j <= 2; j++) {
+			if (i + j < fromwords)
+				ftmp[j] = get_unaligned_le16(&from[i + j]);
+			else
+				ftmp[j] = 0;
+		}
+
+		/*
+		 * 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;
+
+		/*
+		 * charlen (=bytes of UTF-8 for 1 character)
+		 * 4bytes UTF-8(surrogate pair) is charlen=4
+		 * (4bytes UTF-16 code)
+		 * 7-8bytes UTF-8(IVS) is charlen=3+4 or 4+4
+		 * (2 UTF-8 pairs divided to 2 UTF-16 pairs)
+		 */
+		if (charlen == 4)
+			i++;
+		else if (charlen >= 5)
+			/* 5-6bytes UTF-8 */
+			i += 2;
+	}
+
+	/* properly null-terminate string */
+	for (i = 0; i < nullsize; i++)
+		to[outlen++] = 0;
+
+	return outlen;
+}
+
+/*
+ * smb_strtoUTF16() - Convert character string to unicode string
+ * @to:		destination buffer
+ * @from:	source buffer
+ * @len:	destination buffer size (in bytes)
+ * @codepage:	codepage to which characters should be converted
+ *
+ * Return:	string length after conversion
+ */
+int smb_strtoUTF16(__le16 *to, const char *from, int len,
+		   const struct nls_table *codepage)
+{
+	int charlen;
+	int i;
+	wchar_t wchar_to; /* needed to quiet sparse */
+
+	/* 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
+		 */
+	}
+
+	for (i = 0; len > 0 && *from; i++, from += charlen, len -= charlen) {
+		charlen = codepage->char2uni(from, len, &wchar_to);
+		if (charlen < 1) {
+			/* A question mark */
+			wchar_to = 0x003f;
+			charlen = 1;
+		}
+		put_unaligned_le16(wchar_to, &to[i]);
+	}
+
+success:
+	put_unaligned_le16(0, &to[i]);
+	return i;
+}
+
+/*
+ * smb_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.
+ *
+ * Return:	destination string buffer or error ptr
+ */
+char *smb_strndup_from_utf16(const char *src, const int maxlen,
+			     const bool is_unicode,
+			     const struct nls_table *codepage)
+{
+	int len, ret;
+	char *dst;
+
+	if (is_unicode) {
+		len = smb_utf16_bytes((__le16 *)src, maxlen, codepage);
+		len += nls_nullsize(codepage);
+		dst = kmalloc(len, GFP_KERNEL);
+		if (!dst)
+			return ERR_PTR(-ENOMEM);
+		ret = smb_from_utf16(dst, (__le16 *)src, len, maxlen, codepage,
+				     false);
+		if (ret < 0) {
+			kfree(dst);
+			return ERR_PTR(-EINVAL);
+		}
+	} else {
+		len = strnlen(src, maxlen);
+		len++;
+		dst = kmalloc(len, GFP_KERNEL);
+		if (!dst)
+			return ERR_PTR(-ENOMEM);
+		strscpy(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
+ */
+/*
+ * smbConvertToUTF16() - convert string from local charset to utf16
+ * @target:	destination buffer
+ * @source:	source buffer
+ * @srclen:	source buffer size (in bytes)
+ * @cp:		codepage to which characters should be converted
+ * @mapchar:	should characters be remapped according to the mapchars option?
+ *
+ * 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
+ *
+ * Return:	char length after conversion
+ */
+int smbConvertToUTF16(__le16 *target, const char *source, int srclen,
+		      const struct nls_table *cp, int mapchars)
+{
+	int i, j, charlen;
+	char src_char;
+	__le16 dst_char;
+	wchar_t tmp;
+	wchar_t wchar_to[6];	/* UTF-16 */
+	int ret;
+	unicode_t u;
+
+	if (!mapchars)
+		return smb_strtoUTF16(target, source, srclen, cp);
+
+	for (i = 0, j = 0; i < srclen; j++) {
+		src_char = source[i];
+		charlen = 1;
+		switch (src_char) {
+		case 0:
+			put_unaligned(0, &target[j]);
+			return j;
+		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 > 0)
+				goto ctoUTF16;
+
+			/* convert SURROGATE_PAIR */
+			if (strcmp(cp->charset, "utf8"))
+				goto unknown;
+			if (*(source + i) & 0x80) {
+				charlen = utf8_to_utf32(source + i, 6, &u);
+				if (charlen < 0)
+					goto unknown;
+			} else
+				goto unknown;
+			ret  = utf8s_to_utf16s(source + i, charlen,
+					UTF16_LITTLE_ENDIAN,
+					wchar_to, 6);
+			if (ret < 0)
+				goto unknown;
+
+			i += charlen;
+			dst_char = cpu_to_le16(*wchar_to);
+			if (charlen <= 3)
+				/* 1-3bytes UTF-8 to 2bytes UTF-16 */
+				put_unaligned(dst_char, &target[j]);
+			else if (charlen == 4) {
+				/*
+				 * 4bytes UTF-8(surrogate pair) to 4bytes UTF-16
+				 * 7-8bytes UTF-8(IVS) divided to 2 UTF-16
+				 * (charlen=3+4 or 4+4)
+				 */
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 1));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+			} else if (charlen >= 5) {
+				/* 5-6bytes UTF-8 to 6bytes UTF-16 */
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 1));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+				dst_char = cpu_to_le16(*(wchar_to + 2));
+				j++;
+				put_unaligned(dst_char, &target[j]);
+			}
+			continue;
+
+unknown:
+			dst_char = cpu_to_le16(0x003f);
+			charlen = 1;
+		}
+
+ctoUTF16:
+		/*
+		 * 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]);
+	}
+
+	return j;
+}