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Diffstat (limited to 'mysys/my_access.c')
| -rw-r--r-- | mysys/my_access.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/mysys/my_access.c b/mysys/my_access.c new file mode 100644 index 00000000..81e635d9 --- /dev/null +++ b/mysys/my_access.c @@ -0,0 +1,267 @@ +/* Copyright (c) 2000, 2012, Oracle and/or its affiliates + Copyright (c) 2012, 2014, SkySQL Ab + + This program 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; version 2 of the License. + + This program 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; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */ + +#include "mysys_priv.h" +#include <m_string.h> + +#ifdef _WIN32 + +/* + Check a file or path for accessability. + + SYNOPSIS + file_access() + path Path to file + amode Access method + + RETURN VALUES + 0 ok + -1 error (We use -1 as my_access is mapped to access on other platforms) +*/ + +int my_access(const char *path, int amode) +{ + DWORD attributes; + + attributes = GetFileAttributes(path); + if (attributes == INVALID_FILE_ATTRIBUTES || + ((attributes & FILE_ATTRIBUTE_READONLY) && (amode & W_OK))) + { + my_errno= errno= EACCES; + return -1; + } + return 0; +} + +#endif /* _WIN32 */ + + +/* + List of file names that causes problem on windows + + NOTE that one can also not have file names of type CON.TXT + + NOTE: it is important to keep "CLOCK$" on the first place, + we skip it in check_if_legal_tablename. +*/ +static const char *reserved_names[]= +{ + "CLOCK$", + "CON", "PRN", "AUX", "NUL", + "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9", + "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9", + NullS +}; + +#define MAX_RESERVED_NAME_LENGTH 6 + + +/* + Looks up a null-terminated string in a list, + case insensitively. + + SYNOPSIS + str_list_find() + list list of items + str item to find + + RETURN + 0 ok + 1 reserved file name +*/ +static int str_list_find(const char **list, const char *str) +{ + const char **name; + for (name= list; *name; name++) + { + if (!my_strcasecmp(&my_charset_latin1, *name, str)) + return 1; + } + return 0; +} + + +/* + A map for faster reserved_names lookup, + helps to avoid loops in many cases. + 1 - can be the first letter + 2 - can be the second letter + 4 - can be the third letter +*/ +static char reserved_map[256]= +{ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* !"#$%&'()*+,-./ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 0123456789:;<=>? */ + 0,1,0,1,0,0,0,0,0,0,0,0,7,4,5,2, /* @ABCDEFGHIJKLMNO */ + 3,0,2,0,4,2,0,0,4,0,0,0,0,0,0,0, /* PQRSTUVWXYZ[\]^_ */ + 0,1,0,1,0,0,0,0,0,0,0,0,7,4,5,2, /* bcdefghijklmno */ + 3,0,2,0,4,2,0,0,4,0,0,0,0,0,0,0, /* pqrstuvwxyz{|}~. */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* ................ */ + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 /* ................ */ +}; + + +/* + Check if a table name may cause problems + + SYNOPSIS + check_if_legal_tablename + name Table name (without any extensions) + + DESCRIPTION + We don't check 'CLOCK$' because dollar sign is encoded as @0024, + making table file name 'CLOCK@0024', which is safe. + This is why we start lookup from the second element + (i.e. &reserver_name[1]) + + RETURN + 0 ok + 1 reserved file name +*/ + +int check_if_legal_tablename(const char *name) +{ + DBUG_ENTER("check_if_legal_tablename"); + DBUG_RETURN((reserved_map[(uchar) name[0]] & 1) && + (reserved_map[(uchar) name[1]] & 2) && + (reserved_map[(uchar) name[2]] & 4) && + str_list_find(&reserved_names[1], name)); +} + + +#ifdef _WIN32 +/** + Checks if the drive letter supplied is valid or not. Valid drive + letters are A to Z, both lower case and upper case. + + @param drive_letter : The drive letter to validate. + + @return TRUE if the drive exists, FALSE otherwise. +*/ +static my_bool does_drive_exists(char drive_letter) +{ + DWORD drive_mask= GetLogicalDrives(); + drive_letter= toupper(drive_letter); + + return (drive_letter >= 'A' && drive_letter <= 'Z') && + (drive_mask & (0x1 << (drive_letter - 'A'))); +} + +/** + Verifies if the file name supplied is allowed or not. On Windows + file names with a colon (:) are not allowed because such file names + store data in Alternate Data Streams which can be used to hide + the data. + Apart from colon, other characters that are not allowed in filenames + on Windows are greater/less sign, double quotes, forward slash, backslash, + pipe and star characters. + + See MSDN documentation on filename restrictions. + + @param name contains the file name with or without path + @param length contains the length of file name + @param allow_current_dir TRUE if paths like C:foobar are allowed, + FALSE otherwise + + @return TRUE if the file name is allowed, FALSE otherwise. +*/ +#define ILLEGAL_FILENAME_CHARS "<>:\"/\\|?*" + +my_bool is_filename_allowed(const char *name __attribute__((unused)), + size_t length __attribute__((unused)), + my_bool allow_current_dir __attribute__((unused))) +{ + /* + For Windows, check if the file name contains : character. + Start from end of path and search if the file name contains : + */ + const char* ch = NULL; + for (ch= name + length - 1; ch >= name; --ch) + { + if (FN_LIBCHAR == *ch || '/' == *ch) + break; + else if (':' == *ch) + { + /* + File names like C:foobar.txt are allowed since the syntax means + file foobar.txt in current directory of C drive. However file + names likes CC:foobar are not allowed since this syntax means ADS + foobar in file CC. + */ + return (allow_current_dir && (ch - name == 1) && + does_drive_exists(*name)); + } + else if (strchr(ILLEGAL_FILENAME_CHARS, *ch)) + return FALSE; + } + return TRUE; +} /* is_filename_allowed */ +#endif /* _WIN32 */ + +#if defined(_WIN32) + +/* + Check if a path will access a reserved file name that may cause problems + + SYNOPSIS + check_if_legal_filename + path Path to file + + RETURN + 0 ok + 1 reserved file name +*/ + +int check_if_legal_filename(const char *path) +{ + const char *end; + const char **reserved_name; + DBUG_ENTER("check_if_legal_filename"); + + if (!is_filename_allowed(path, strlen(path), TRUE)) + DBUG_RETURN(1); + + path+= dirname_length(path); /* To start of filename */ + if (!(end= strchr(path, FN_EXTCHAR))) + end= strend(path); + if (path == end || (uint) (end - path) > MAX_RESERVED_NAME_LENGTH) + DBUG_RETURN(0); /* Simplify inner loop */ + + for (reserved_name= reserved_names; *reserved_name; reserved_name++) + { + const char *reserved= *reserved_name; /* never empty */ + const char *name= path; + + do + { + if (*reserved != my_toupper(&my_charset_latin1, *name)) + break; + if (++name == end && !reserved[1]) + DBUG_RETURN(1); /* Found wrong path */ + } while (*++reserved); + } + DBUG_RETURN(0); +} + +#endif /* defined(_WIN32) */ |