Commit 484a10f4 authored by Andrew Gabbasov's avatar Andrew Gabbasov Committed by Jan Kara
Browse files

udf: Merge linux specific translation into CS0 conversion function 



Current implementation of udf_translate_to_linux function does not
support multi-bytes characters at all: it counts bytes while calculating
extension length, when inserting CRC inside the name it doesn't
take into account inter-character boundaries and can break into
the middle of the character.

The most efficient way to properly support multi-bytes characters is
merging of translation operations directly into conversion function.
This can help to avoid extra passes along the string or parsing
the multi-bytes character back into unicode to find out it's length.

Signed-off-by: default avatarAndrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent 9293fcfb

fs/udf/unicode.c

+152 −128
Original line number Diff line number Diff line
@@ -28,9 +28,6 @@ 


#include "udf_sb.h"



static int udf_translate_to_linux(uint8_t *, int, const uint8_t *, int,

				  const uint8_t *, int);



static int udf_uni2char_utf8(wchar_t uni,

			     unsigned char *out,

			     int boundlen)
@@ -114,13 +111,83 @@ static int udf_char2uni_utf8(const unsigned char *in, 
	return u_len;

}



#define ILLEGAL_CHAR_MARK	'_'

#define EXT_MARK		'.'

#define CRC_MARK		'#'

#define EXT_SIZE		5

/* Number of chars we need to store generated CRC to make filename unique */

#define CRC_LEN			5



static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len,

			      int *str_o_idx,

			      const uint8_t *str_i, int str_i_max_len,

			      int *str_i_idx,

			      int u_ch, int *needsCRC,

			      int (*conv_f)(wchar_t, unsigned char *, int),

			      int translate)

{

	uint32_t c;

	int illChar = 0;

	int len, gotch = 0;



	for (; (!gotch) && (*str_i_idx < str_i_max_len); *str_i_idx += u_ch) {

		if (*str_o_idx >= str_o_max_len) {

			*needsCRC = 1;

			return gotch;

		}



		/* Expand OSTA compressed Unicode to Unicode */

		c = str_i[*str_i_idx];

		if (u_ch > 1)

			c = (c << 8) | str_i[*str_i_idx + 1];



		if (translate && (c == '/' || c == 0))

			illChar = 1;

		else if (illChar)

			break;

		else

			gotch = 1;

	}

	if (illChar) {

		*needsCRC = 1;

		c = ILLEGAL_CHAR_MARK;

		gotch = 1;

	}

	if (gotch) {

		len = conv_f(c, &str_o[*str_o_idx], str_o_max_len - *str_o_idx);

		/* Valid character? */

		if (len >= 0)

			*str_o_idx += len;

		else if (len == -ENAMETOOLONG) {

			*needsCRC = 1;

			gotch = 0;

		} else {

			str_o[(*str_o_idx)++] = '?';

			*needsCRC = 1;

		}

	}

	return gotch;

}



static int udf_name_from_CS0(uint8_t *str_o, int str_max_len,

			     const uint8_t *ocu, int ocu_len,

			     int (*conv_f)(wchar_t, unsigned char *, int))

			     int (*conv_f)(wchar_t, unsigned char *, int),

			     int translate)

{

	uint32_t c;

	uint8_t cmp_id;

	int i, len;

	int str_o_len = 0;

	int idx, len;

	int u_ch;

	int needsCRC = 0;

	int ext_i_len, ext_max_len;

	int str_o_len = 0;	/* Length of resulting output */

	int ext_o_len = 0;	/* Extension output length */

	int ext_crc_len = 0;	/* Extension output length if used with CRC */

	int i_ext = -1;		/* Extension position in input buffer */

	int o_crc = 0;		/* Rightmost possible output pos for CRC+ext */

	unsigned short valueCRC;

	uint8_t ext[EXT_SIZE * NLS_MAX_CHARSET_SIZE + 1];

	uint8_t crc[CRC_LEN];



	if (str_max_len <= 0)

		return 0;
@@ -133,24 +200,88 @@ static int udf_name_from_CS0(uint8_t *str_o, int str_max_len, 
	cmp_id = ocu[0];

	if (cmp_id != 8 && cmp_id != 16) {

		memset(str_o, 0, str_max_len);

		pr_err("unknown compression code (%d) stri=%s\n", cmp_id, ocu);

		pr_err("unknown compression code (%d)\n", cmp_id);

		return -EINVAL;

	}

	u_ch = cmp_id >> 3;



	for (i = 1; (i < ocu_len) && (str_o_len < str_max_len);) {

		/* Expand OSTA compressed Unicode to Unicode */

		uint32_t c = ocu[i++];

		if (cmp_id == 16)

			c = (c << 8) | ocu[i++];

	ocu++;

	ocu_len--;



		len = conv_f(c, &str_o[str_o_len], str_max_len - str_o_len);

		/* Valid character? */

		if (len >= 0)

			str_o_len += len;

		else if (len == -ENAMETOOLONG)

	if (ocu_len % u_ch) {

		pr_err("incorrect filename length (%d)\n", ocu_len + 1);

		return -EINVAL;

	}



	if (translate) {

		/* Look for extension */

		for (idx = ocu_len - u_ch, ext_i_len = 0;

		     (idx >= 0) && (ext_i_len < EXT_SIZE);

		     idx -= u_ch, ext_i_len++) {

			c = ocu[idx];

			if (u_ch > 1)

				c = (c << 8) | ocu[idx + 1];



			if (c == EXT_MARK) {

				if (ext_i_len)

					i_ext = idx;

				break;

			}

		}

		if (i_ext >= 0) {

			/* Convert extension */

			ext_max_len = min_t(int, sizeof(ext), str_max_len);

			ext[ext_o_len++] = EXT_MARK;

			idx = i_ext + u_ch;

			while (udf_name_conv_char(ext, ext_max_len, &ext_o_len,

						  ocu, ocu_len, &idx,

						  u_ch, &needsCRC,

						  conv_f, translate)) {

				if ((ext_o_len + CRC_LEN) < str_max_len)

					ext_crc_len = ext_o_len;

			}

		}

	}



	idx = 0;

	while (1) {

		if (translate && (idx == i_ext)) {

			if (str_o_len > (str_max_len - ext_o_len))

				needsCRC = 1;

			break;

		else

			str_o[str_o_len++] = '?';

		}



		if (!udf_name_conv_char(str_o, str_max_len, &str_o_len,

					ocu, ocu_len, &idx,

					u_ch, &needsCRC, conv_f, translate))

			break;



		if (translate &&

		    (str_o_len <= (str_max_len - ext_o_len - CRC_LEN)))

			o_crc = str_o_len;

	}



	if (translate) {

		if (str_o_len <= 2 && str_o[0] == '.' &&

		    (str_o_len == 1 || str_o[1] == '.'))

			needsCRC = 1;

		if (needsCRC) {

			str_o_len = o_crc;

			valueCRC = crc_itu_t(0, ocu, ocu_len);

			crc[0] = CRC_MARK;

			crc[1] = hex_asc_upper_hi(valueCRC >> 8);

			crc[2] = hex_asc_upper_lo(valueCRC >> 8);

			crc[3] = hex_asc_upper_hi(valueCRC);

			crc[4] = hex_asc_upper_lo(valueCRC);

			len = min_t(int, CRC_LEN, str_max_len - str_o_len);

			memcpy(&str_o[str_o_len], crc, len);

			str_o_len += len;

			ext_o_len = ext_crc_len;

		}

		if (ext_o_len > 0) {

			memcpy(&str_o[str_o_len], ext, ext_o_len);

			str_o_len += ext_o_len;

		}

	}



	return str_o_len;
@@ -207,13 +338,12 @@ try_again: 
int udf_CS0toUTF8(uint8_t *utf_o, int o_len, const uint8_t *ocu_i, int i_len)

{

	return udf_name_from_CS0(utf_o, o_len, ocu_i, i_len,

				 udf_uni2char_utf8);

				 udf_uni2char_utf8, 0);

}



int udf_get_filename(struct super_block *sb, const uint8_t *sname, int slen,

		     uint8_t *dname, int dlen)

{

	uint8_t *filename;

	int (*conv_f)(wchar_t, unsigned char *, int);

	int ret;
@@ -223,10 +353,6 @@ int udf_get_filename(struct super_block *sb, const uint8_t *sname, int slen, 
	if (dlen <= 0)

		return 0;



	filename = kmalloc(dlen, GFP_NOFS);

	if (!filename)

		return -ENOMEM;



	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {

		conv_f = udf_uni2char_utf8;

	} else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
@@ -234,19 +360,10 @@ int udf_get_filename(struct super_block *sb, const uint8_t *sname, int slen, 
	} else

		BUG();



	ret = udf_name_from_CS0(filename, dlen, sname, slen, conv_f);

	if (ret < 0) {

		udf_debug("Failed in udf_get_filename: sname = %s\n", sname);

		goto out2;

	}



	ret = udf_translate_to_linux(dname, dlen, filename, dlen,

				     sname + 1, slen - 1);

	ret = udf_name_from_CS0(dname, dlen, sname, slen, conv_f, 1);

	/* Zero length filename isn't valid... */

	if (ret == 0)

		ret = -EINVAL;

out2:

	kfree(filename);

	return ret;

}
@@ -265,96 +382,3 @@ int udf_put_filename(struct super_block *sb, const uint8_t *sname, int slen, 
	return udf_name_to_CS0(dname, dlen, sname, slen, conv_f);

}

#define ILLEGAL_CHAR_MARK	'_'

#define EXT_MARK		'.'

#define CRC_MARK		'#'

#define EXT_SIZE 		5

/* Number of chars we need to store generated CRC to make filename unique */

#define CRC_LEN			5



static int udf_translate_to_linux(uint8_t *newName, int newLen,

				  const uint8_t *udfName, int udfLen,

				  const uint8_t *fidName, int fidNameLen)

{

	int index, newIndex = 0, needsCRC = 0;

	int extIndex = 0, newExtIndex = 0, hasExt = 0;

	unsigned short valueCRC;

	uint8_t curr;



	if (udfName[0] == '.' &&

	    (udfLen == 1 || (udfLen == 2 && udfName[1] == '.'))) {

		needsCRC = 1;

		newIndex = udfLen;

		memcpy(newName, udfName, udfLen);

	} else {

		for (index = 0; index < udfLen; index++) {

			curr = udfName[index];

			if (curr == '/' || curr == 0) {

				needsCRC = 1;

				curr = ILLEGAL_CHAR_MARK;

				while (index + 1 < udfLen &&

						(udfName[index + 1] == '/' ||

						 udfName[index + 1] == 0))

					index++;

			}

			if (curr == EXT_MARK &&

					(udfLen - index - 1) <= EXT_SIZE) {

				if (udfLen == index + 1)

					hasExt = 0;

				else {

					hasExt = 1;

					extIndex = index;

					newExtIndex = newIndex;

				}

			}

			if (newIndex < newLen)

				newName[newIndex++] = curr;

			else

				needsCRC = 1;

		}

	}

	if (needsCRC) {

		uint8_t ext[EXT_SIZE];

		int localExtIndex = 0;



		if (hasExt) {

			int maxFilenameLen;

			for (index = 0;

			     index < EXT_SIZE && extIndex + index + 1 < udfLen;

			     index++) {

				curr = udfName[extIndex + index + 1];



				if (curr == '/' || curr == 0) {

					needsCRC = 1;

					curr = ILLEGAL_CHAR_MARK;

					while (extIndex + index + 2 < udfLen &&

					      (index + 1 < EXT_SIZE &&

						(udfName[extIndex + index + 2] == '/' ||

						 udfName[extIndex + index + 2] == 0)))

						index++;

				}

				ext[localExtIndex++] = curr;

			}

			maxFilenameLen = newLen - CRC_LEN - localExtIndex;

			if (newIndex > maxFilenameLen)

				newIndex = maxFilenameLen;

			else

				newIndex = newExtIndex;

		} else if (newIndex > newLen - CRC_LEN)

			newIndex = newLen - CRC_LEN;

		newName[newIndex++] = CRC_MARK;

		valueCRC = crc_itu_t(0, fidName, fidNameLen);

		newName[newIndex++] = hex_asc_upper_hi(valueCRC >> 8);

		newName[newIndex++] = hex_asc_upper_lo(valueCRC >> 8);

		newName[newIndex++] = hex_asc_upper_hi(valueCRC);

		newName[newIndex++] = hex_asc_upper_lo(valueCRC);



		if (hasExt) {

			newName[newIndex++] = EXT_MARK;

			for (index = 0; index < localExtIndex; index++)

				newName[newIndex++] = ext[index];

		}

	}



	return newIndex;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE