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-rw-r--r--src/tool_doswin.c448
1 files changed, 349 insertions, 99 deletions
diff --git a/src/tool_doswin.c b/src/tool_doswin.c
index 6cad193ce..6e1fe0ed3 100644
--- a/src/tool_doswin.c
+++ b/src/tool_doswin.c
@@ -85,52 +85,113 @@ __pragma(warning(pop))
# include <fcntl.h> /* _use_lfn(f) prototype */
#endif
+#ifndef UNITTESTS
+static SANITIZEcode truncate_dryrun(const char *path,
+ const size_t truncate_pos);
#ifdef MSDOS
-static char *msdosify(const char *file_name);
+static SANITIZEcode msdosify(char **const sanitized, const char *file_name,
+ int flags);
#endif
-static char *rename_if_dos_device_name(const char *file_name);
+static SANITIZEcode rename_if_reserved_dos_device_name(char **const sanitized,
+ const char *file_name,
+ int flags);
+#endif /* !UNITTESTS (static declarations used if no unit tests) */
/*
-Sanitize *file_name.
-Success: (CURLE_OK) *file_name points to a sanitized version of the original.
- This function takes ownership of the original *file_name and frees it.
-Failure: (!= CURLE_OK) *file_name is unchanged.
+Sanitize a file or path name.
+
+All banned characters are replaced by underscores, for example:
+f?*foo => f__foo
+f:foo::$DATA => f_foo__$DATA
+f:\foo:bar => f__foo_bar
+f:\foo:bar => f:\foo:bar (flag SANITIZE_ALLOW_PATH)
+
+This function was implemented according to the guidelines in 'Naming Files,
+Paths, and Namespaces' section 'Naming Conventions'.
+https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247.aspx
+
+Flags
+-----
+SANITIZE_ALLOW_COLONS: Allow colons.
+Without this flag colons are sanitized.
+
+SANITIZE_ALLOW_PATH: Allow path separators and colons.
+Without this flag path separators and colons are sanitized.
+
+SANITIZE_ALLOW_RESERVED: Allow reserved device names.
+Without this flag a reserved device name is renamed (COM1 => _COM1) unless it's
+in a UNC prefixed path.
+
+SANITIZE_ALLOW_TRUNCATE: Allow truncating a long filename.
+Without this flag if the sanitized filename or path will be too long an error
+occurs. With this flag the filename --and not any other parts of the path-- may
+be truncated to at least a single character. A filename followed by an
+alternate data stream (ADS) cannot be truncated in any case.
+
+Success: (SANITIZE_ERR_OK) *sanitized points to a sanitized copy of file_name.
+Failure: (!= SANITIZE_ERR_OK) *sanitized is NULL.
*/
-CURLcode sanitize_file_name(char **file_name)
+SANITIZEcode sanitize_file_name(char **const sanitized, const char *file_name,
+ int flags)
{
+ char *p, *target;
size_t len;
- char *p, *sanitized;
+ CURLcode res;
+ size_t max_sanitized_len;
- /* Calculate the maximum length of a filename.
- FILENAME_MAX is often the same as PATH_MAX, in other words it does not
- discount the path information. PATH_MAX size is calculated based on:
- <drive-letter><colon><path-sep><max-filename-len><NULL> */
- const size_t max_filename_len = PATH_MAX - 3 - 1;
-
- if(!file_name || !*file_name)
- return CURLE_BAD_FUNCTION_ARGUMENT;
+ if(!sanitized)
+ return SANITIZE_ERR_BAD_ARGUMENT;
- len = strlen(*file_name);
+ *sanitized = NULL;
- if(len >= max_filename_len)
- len = max_filename_len - 1;
+ if(!file_name)
+ return SANITIZE_ERR_BAD_ARGUMENT;
- sanitized = malloc(len + 1);
+ if((flags & SANITIZE_ALLOW_PATH)) {
+#ifndef MSDOS
+ if((flags & SANITIZE_ALLOW_PATH) &&
+ file_name[0] == '\\' && file_name[1] == '\\')
+ /* UNC prefixed path, eg \\?\C:\foo */
+ max_sanitized_len = 32767-1;
+ else
+#endif
+ max_sanitized_len = PATH_MAX-1;
+ }
+ else
+ /* The maximum length of a filename.
+ FILENAME_MAX is often the same as PATH_MAX, in other words it is 260 and
+ does not discount the path information therefore we shouldn't use it. */
+ max_sanitized_len = (PATH_MAX-1 > 255) ? 255 : PATH_MAX-1;
+
+ len = strlen(file_name);
+ if(len > max_sanitized_len) {
+ if(!(flags & SANITIZE_ALLOW_TRUNCATE) ||
+ truncate_dryrun(file_name, max_sanitized_len))
+ return SANITIZE_ERR_INVALID_PATH;
+
+ len = max_sanitized_len;
+ }
- if(!sanitized)
- return CURLE_OUT_OF_MEMORY;
+ target = malloc(len + 1);
+ if(!target)
+ return SANITIZE_ERR_OUT_OF_MEMORY;
- strncpy(sanitized, *file_name, len);
- sanitized[len] = '\0';
+ strncpy(target, file_name, len);
+ target[len] = '\0';
- for(p = sanitized; *p; ++p ) {
+ /* replace control characters and other banned characters */
+ for(p = target; *p; ++p) {
const char *banned;
- if(1 <= *p && *p <= 31) {
+
+ if((1 <= *p && *p <= 31) ||
+ (!(flags & (SANITIZE_ALLOW_COLONS|SANITIZE_ALLOW_PATH)) && *p == ':') ||
+ (!(flags & SANITIZE_ALLOW_PATH) && (*p == '/' || *p == '\\'))) {
*p = '_';
continue;
}
- for(banned = "|<>/\\\":?*"; *banned; ++banned) {
+
+ for(banned = "|<>\"?*"; *banned; ++banned) {
if(*p == *banned) {
*p = '_';
break;
@@ -138,39 +199,111 @@ CURLcode sanitize_file_name(char **file_name)
}
}
+ /* remove trailing spaces and periods if not allowing paths */
+ if(!(flags & SANITIZE_ALLOW_PATH) && len) {
+ char *clip = NULL;
+
+ p = &target[len];
+ do {
+ --p;
+ if(*p != ' ' && *p != '.')
+ break;
+ clip = p;
+ } while(p != target);
+
+ if(clip) {
+ *clip = '\0';
+ len = clip - target;
+ }
+ }
+
#ifdef MSDOS
- /* msdosify checks for more banned characters for MSDOS, however it allows
- for some path information to pass through. since we are sanitizing only a
- filename and cannot allow a path it's important this call be done in
- addition to and not instead of the banned character check above. */
- p = msdosify(sanitized);
- if(!p) {
- free(sanitized);
- return CURLE_BAD_FUNCTION_ARGUMENT;
+ res = msdosify(&p, target, flags);
+ free(target);
+ if(res)
+ return res;
+ target = p;
+ len = strlen(target);
+
+ if(len > max_sanitized_len) {
+ free(target);
+ return SANITIZE_ERR_INVALID_PATH;
}
- sanitized = p;
- len = strlen(sanitized);
#endif
- p = rename_if_dos_device_name(sanitized);
- if(!p) {
- free(sanitized);
- return CURLE_BAD_FUNCTION_ARGUMENT;
+ if(!(flags & SANITIZE_ALLOW_RESERVED)) {
+ res = rename_if_reserved_dos_device_name(&p, target, flags);
+ free(target);
+ if(res)
+ return res;
+ target = p;
+ len = strlen(target);
+
+ if(len > max_sanitized_len) {
+ free(target);
+ return SANITIZE_ERR_INVALID_PATH;
+ }
}
- sanitized = p;
- len = strlen(sanitized);
-
- /* dos_device_name rename will rename a device name, possibly changing the
- length. If the length is too long now we can't truncate it because we
- could end up with a device name. In practice this shouldn't be a problem
- because device names are short, but you never know. */
- if(len >= max_filename_len) {
- free(sanitized);
- return CURLE_BAD_FUNCTION_ARGUMENT;
+
+ *sanitized = target;
+ return SANITIZE_ERR_OK;
+}
+
+
+/*
+Test if truncating a path to a file will leave at least a single character in
+the filename. Filenames suffixed by an alternate data stream can't be
+truncated. This performs a dry run, nothing is modified.
+
+Good truncate_pos 9: C:\foo\bar => C:\foo\ba
+Good truncate_pos 6: C:\foo => C:\foo
+Good truncate_pos 5: C:\foo => C:\fo
+Bad* truncate_pos 5: C:foo => C:foo
+Bad truncate_pos 5: C:\foo:ads => C:\fo
+Bad truncate_pos 9: C:\foo:ads => C:\foo:ad
+Bad truncate_pos 5: C:\foo\bar => C:\fo
+Bad truncate_pos 5: C:\foo\ => C:\fo
+Bad truncate_pos 7: C:\foo\ => C:\foo\
+Error truncate_pos 7: C:\foo => (pos out of range)
+Bad truncate_pos 1: C:\foo\ => C
+
+* C:foo is ambiguous, C could end up being a drive or file therefore something
+ like C:superlongfilename can't be truncated.
+
+Returns
+SANITIZE_ERR_OK: Good -- 'path' can be truncated
+SANITIZE_ERR_INVALID_PATH: Bad -- 'path' cannot be truncated
+!= SANITIZE_ERR_OK && != SANITIZE_ERR_INVALID_PATH: Error
+*/
+SANITIZEcode truncate_dryrun(const char *path, const size_t truncate_pos)
+{
+ size_t len;
+
+ if(!path)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ len = strlen(path);
+
+ if(truncate_pos > len)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ if(!len || !truncate_pos)
+ return SANITIZE_ERR_INVALID_PATH;
+
+ if(strpbrk(&path[truncate_pos - 1], "\\/:"))
+ return SANITIZE_ERR_INVALID_PATH;
+
+ /* C:\foo can be truncated but C:\foo:ads can't */
+ if(truncate_pos > 1) {
+ const char *p = &path[truncate_pos - 1];
+ do {
+ --p;
+ if(*p == ':')
+ return SANITIZE_ERR_INVALID_PATH;
+ } while(p != path && *p != '\\' && *p != '/');
}
- *file_name = sanitized;
- return CURLE_OK;
+ return SANITIZE_ERR_OK;
}
/* The functions msdosify, rename_if_dos_device_name and __crt0_glob_function
@@ -180,16 +313,24 @@ CURLcode sanitize_file_name(char **file_name)
/*
Extra sanitization MSDOS for file_name.
-Returns a copy of file_name that is sanitized by MSDOS standards.
-Warning: path information may pass through. For sanitizing a filename use
-sanitize_file_name which calls this function after sanitizing path info.
+
+This is a supporting function for sanitize_file_name.
+
+Warning: This is an MSDOS legacy function and was purposely written in a way
+that some path information may pass through. For example drive letter names
+(C:, D:, etc) are allowed to pass through. For sanitizing a filename use
+sanitize_file_name.
+
+Success: (SANITIZE_ERR_OK) *sanitized points to a sanitized copy of file_name.
+Failure: (!= SANITIZE_ERR_OK) *sanitized is NULL.
*/
-#ifdef MSDOS
-static char *msdosify(const char *file_name)
+#if defined(MSDOS) || defined(UNITTESTS)
+SANITIZEcode msdosify(char **const sanitized, const char *file_name,
+ int flags)
{
char dos_name[PATH_MAX];
static const char illegal_chars_dos[] = ".+, ;=[]" /* illegal in DOS */
- "|<>\\\":?*"; /* illegal in DOS & W95 */
+ "|<>/\\\":?*"; /* illegal in DOS & W95 */
static const char *illegal_chars_w95 = &illegal_chars_dos[8];
int idx, dot_idx;
const char *s = file_name;
@@ -198,6 +339,19 @@ static char *msdosify(const char *file_name)
const char *illegal_aliens = illegal_chars_dos;
size_t len = sizeof(illegal_chars_dos) - 1;
+ if(!sanitized)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ *sanitized = NULL;
+
+ if(!file_name)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ if(strlen(file_name) > PATH_MAX-1 &&
+ (!(flags & SANITIZE_ALLOW_TRUNCATE) ||
+ truncate_dryrun(file_name, PATH_MAX-1)))
+ return SANITIZE_ERR_INVALID_PATH;
+
/* Support for Windows 9X VFAT systems, when available. */
if(_use_lfn(file_name)) {
illegal_aliens = illegal_chars_w95;
@@ -207,22 +361,35 @@ static char *msdosify(const char *file_name)
/* Get past the drive letter, if any. */
if(s[0] >= 'A' && s[0] <= 'z' && s[1] == ':') {
*d++ = *s++;
- *d++ = *s++;
+ *d = ((flags & (SANITIZE_ALLOW_COLONS|SANITIZE_ALLOW_PATH))) ? ':' : '_';
+ ++d, ++s;
}
for(idx = 0, dot_idx = -1; *s && d < dlimit; s++, d++) {
if(memchr(illegal_aliens, *s, len)) {
+
+ if((flags & (SANITIZE_ALLOW_COLONS|SANITIZE_ALLOW_PATH)) && *s == ':')
+ *d = ':';
+ else if((flags & SANITIZE_ALLOW_PATH) && (*s == '/' || *s == '\\'))
+ *d = *s;
/* Dots are special: DOS doesn't allow them as the leading character,
and a file name cannot have more than a single dot. We leave the
first non-leading dot alone, unless it comes too close to the
beginning of the name: we want sh.lex.c to become sh_lex.c, not
sh.lex-c. */
- if(*s == '.') {
- if(idx == 0 && (s[1] == '/' || (s[1] == '.' && s[2] == '/'))) {
+ else if(*s == '.') {
+ if((flags & SANITIZE_ALLOW_PATH) && idx == 0 &&
+ (s[1] == '/' || s[1] == '\\' ||
+ (s[1] == '.' && (s[2] == '/' || s[2] == '\\')))) {
/* Copy "./" and "../" verbatim. */
*d++ = *s++;
- if(*s == '.')
+ if(d == dlimit)
+ break;
+ if(*s == '.') {
*d++ = *s++;
+ if(d == dlimit)
+ break;
+ }
*d = *s;
}
else if(idx == 0)
@@ -244,12 +411,22 @@ static char *msdosify(const char *file_name)
else if(*s == '+' && s[1] == '+') {
if(idx - 2 == dot_idx) { /* .c++, .h++ etc. */
*d++ = 'x';
+ if(d == dlimit)
+ break;
*d = 'x';
}
else {
/* libg++ etc. */
- memcpy (d, "plus", 4);
- d += 3;
+ if(dlimit - d < 4) {
+ *d++ = 'x';
+ if(d == dlimit)
+ break;
+ *d = 'x';
+ }
+ else {
+ memcpy (d, "plus", 4);
+ d += 3;
+ }
}
s++;
idx++;
@@ -259,56 +436,90 @@ static char *msdosify(const char *file_name)
}
else
*d = *s;
- if(*s == '/') {
+ if(*s == '/' || *s == '\\') {
idx = 0;
dot_idx = -1;
}
else
idx++;
}
-
*d = '\0';
- return strdup(dos_name);
+
+ if(*s) {
+ /* dos_name is truncated, check that truncation requirements are met,
+ specifically truncating a filename suffixed by an alternate data stream
+ or truncating the entire filename is not allowed. */
+ if(!(flags & SANITIZE_ALLOW_TRUNCATE) || strpbrk(s, "\\/:") ||
+ truncate_dryrun(dos_name, d - dos_name))
+ return SANITIZE_ERR_INVALID_PATH;
+ }
+
+ *sanitized = strdup(dos_name);
+ return (*sanitized ? SANITIZE_ERR_OK : SANITIZE_ERR_OUT_OF_MEMORY);
}
-#endif
+#endif /* MSDOS || UNITTESTS */
/*
-Rename file_name if it's a representation of a device name.
-Returns a copy of file_name, and the copy will have contents different from the
-original if a device name was found.
+Rename file_name if it's a reserved dos device name.
+
+This is a supporting function for sanitize_file_name.
+
+Warning: This is an MSDOS legacy function and was purposely written in a way
+that some path information may pass through. For example drive letter names
+(C:, D:, etc) are allowed to pass through. For sanitizing a filename use
+sanitize_file_name.
+
+Success: (SANITIZE_ERR_OK) *sanitized points to a sanitized copy of file_name.
+Failure: (!= SANITIZE_ERR_OK) *sanitized is NULL.
*/
-static char *rename_if_dos_device_name(const char *file_name)
+SANITIZEcode rename_if_reserved_dos_device_name(char **const sanitized,
+ const char *file_name,
+ int flags)
{
/* We could have a file whose name is a device on MS-DOS. Trying to
* retrieve such a file would fail at best and wedge us at worst. We need
* to rename such files. */
char *p, *base;
- struct_stat st_buf;
char fname[PATH_MAX];
+#ifdef MSDOS
+ struct_stat st_buf;
+#endif
+
+ if(!sanitized)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ *sanitized = NULL;
+
+ if(!file_name)
+ return SANITIZE_ERR_BAD_ARGUMENT;
+
+ /* Ignore UNC prefixed paths, they are allowed to contain a reserved name. */
+#ifndef MSDOS
+ if((flags & SANITIZE_ALLOW_PATH) &&
+ file_name[0] == '\\' && file_name[1] == '\\') {
+ size_t len = strlen(file_name);
+ *sanitized = malloc(len + 1);
+ if(!*sanitized)
+ return SANITIZE_ERR_OUT_OF_MEMORY;
+ strncpy(*sanitized, file_name, len + 1);
+ return SANITIZE_ERR_OK;
+ }
+#endif
+
+ if(strlen(file_name) > PATH_MAX-1 &&
+ (!(flags & SANITIZE_ALLOW_TRUNCATE) ||
+ truncate_dryrun(file_name, PATH_MAX-1)))
+ return SANITIZE_ERR_INVALID_PATH;
strncpy(fname, file_name, PATH_MAX-1);
fname[PATH_MAX-1] = '\0';
base = basename(fname);
- if(((stat(base, &st_buf)) == 0) && (S_ISCHR(st_buf.st_mode))) {
- size_t blen = strlen(base);
-
- if(strlen(fname) == PATH_MAX-1) {
- /* Make room for the '_' */
- blen--;
- base[blen] = '\0';
- }
- /* Prepend a '_'. */
- memmove(base + 1, base, blen + 1);
- base[0] = '_';
- }
-
- /* The above stat check does not identify devices for me in Windows 7. For
- example a stat on COM1 returns a regular file S_IFREG. According to MSDN
- stat doc that is the correct behavior, so I assume the above code is
- legacy, maybe MSDOS or DJGPP specific? */
- /* Rename devices.
- Examples: CON => _CON, CON.EXT => CON_EXT, CON:ADS => CON_ADS */
+ /* Rename reserved device names that are known to be accessible without \\.\
+ Examples: CON => _CON, CON.EXT => CON_EXT, CON:ADS => CON_ADS
+ https://support.microsoft.com/en-us/kb/74496
+ https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247.aspx
+ */
for(p = fname; p; p = (p == fname && fname != base ? base : NULL)) {
size_t p_len;
int x = (curl_strnequal(p, "CON", 3) ||
@@ -323,31 +534,70 @@ static char *rename_if_dos_device_name(const char *file_name)
continue;
/* the devices may be accessible with an extension or ADS, for
- example CON.AIR and CON:AIR both access console */
- if(p[x] == '.' || p[x] == ':') {
+ example CON.AIR and 'CON . AIR' and CON:AIR access console */
+
+ for(; p[x] == ' '; ++x)
+ ;
+
+ if(p[x] == '.') {
p[x] = '_';
continue;
}
+ else if(p[x] == ':') {
+ if(!(flags & (SANITIZE_ALLOW_COLONS|SANITIZE_ALLOW_PATH))) {
+ p[x] = '_';
+ continue;
+ }
+ ++x;
+ }
else if(p[x]) /* no match */
continue;
+ /* p points to 'CON' or 'CON ' or 'CON:', etc */
p_len = strlen(p);
+ /* Prepend a '_' */
if(strlen(fname) == PATH_MAX-1) {
- /* Make room for the '_' */
- p_len--;
+ --p_len;
+ if(!(flags & SANITIZE_ALLOW_TRUNCATE) || truncate_dryrun(p, p_len))
+ return SANITIZE_ERR_INVALID_PATH;
p[p_len] = '\0';
}
- /* Prepend a '_'. */
memmove(p + 1, p, p_len + 1);
p[0] = '_';
+ ++p_len;
/* if fname was just modified then the basename pointer must be updated */
if(p == fname)
base = basename(fname);
}
- return strdup(fname);
+ /* This is the legacy portion from rename_if_dos_device_name that checks for
+ reserved device names. It only works on MSDOS. On Windows XP the stat
+ check errors with EINVAL if the device name is reserved. On Windows
+ Vista/7/8 it sets mode S_IFREG (regular file or device). According to MSDN
+ stat doc the latter behavior is correct, but that doesn't help us identify
+ whether it's a reserved device name and not a regular file name. */
+#ifdef MSDOS
+ if(base && ((stat(base, &st_buf)) == 0) && (S_ISCHR(st_buf.st_mode))) {
+ /* Prepend a '_' */
+ size_t blen = strlen(base);
+ if(blen) {
+ if(strlen(fname) == PATH_MAX-1) {
+ --blen;
+ if(!(flags & SANITIZE_ALLOW_TRUNCATE) || truncate_dryrun(base, blen))
+ return SANITIZE_ERR_INVALID_PATH;
+ base[blen] = '\0';
+ }
+ memmove(base + 1, base, blen + 1);
+ base[0] = '_';
+ ++blen;
+ }
+ }
+#endif
+
+ *sanitized = strdup(fname);
+ return (*sanitized ? SANITIZE_ERR_OK : SANITIZE_ERR_OUT_OF_MEMORY);
}
#if defined(MSDOS) && (defined(__DJGPP__) || defined(__GO32__))