From dad9228494e3cc03dc477e8109f43119390b53c4 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Mon, 9 Dec 2019 15:52:38 +0100 Subject: Only check for OS specific bad filenames when unpacking When converting a SquashFS image to a tarball, it makes no sense to refuse conversion if the filename is considered evil by the OS. This patch adds an option to is_filename_sane to check if the OS has a problem with the given file name. sqfs2tar sets it to false and converts everything while rdsquashfs sets it to true when unpacking. Signed-off-by: David Oberhollenzer --- lib/common/filename_sane.c | 46 +++++++++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 17 deletions(-) (limited to 'lib/common') diff --git a/lib/common/filename_sane.c b/lib/common/filename_sane.c index d089ba4..56f1127 100644 --- a/lib/common/filename_sane.c +++ b/lib/common/filename_sane.c @@ -8,28 +8,24 @@ #include +#ifdef _WIN32 #ifdef _MSC_VER #define strncasecmp _strnicmp #define strcasecmp _stricmp #endif static const char *bad_names[] = { - ".", - "..", -#ifdef _WIN32 "CON", "PRN", "AUX", "NUL", "COM1", "COM2", "COM3", "COM4", "COM5", "COM6", "COM7", "COM8", "COM9", "LPT1", "LPT2", "LPT3", "LPT4", "LPT5", "LPT6", "LPT7", "LPT8", "LPT9", -#endif }; -bool is_filename_sane(const char *name) +static bool is_allowed_by_os(const char *name) { - size_t i = 0; + size_t len, i; for (i = 0; i < sizeof(bad_names) / sizeof(bad_names[0]); ++i) { -#ifdef _WIN32 - size_t len = strlen(bad_names[i]); + len = strlen(bad_names[i]); if (strncasecmp(name, bad_names[i], len) != 0) continue; @@ -39,23 +35,39 @@ bool is_filename_sane(const char *name) if (name[len] == '.' && strchr(name + len + 1, '.') == NULL) return false; + } + + return true; +} #else - if (strcmp(name, bad_names[i]) == 0) - return false; +static bool is_allowed_by_os(const char *name) +{ + (void)name; + return true; +} #endif - } + +bool is_filename_sane(const char *name, bool check_os_specific) +{ + if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0) + return false; + + if (check_os_specific && !is_allowed_by_os(name)) + return false; while (*name != '\0') { if (*name == '/' || *name == '\\') return false; #ifdef _WIN32 - if (*name == '<' || *name == '>' || *name == ':') - return false; - if (*name == '"' || *name == '|' || *name == '?') - return false; - if (*name == '*' || *name <= 31) - return false; + if (check_os_specific) { + if (*name == '<' || *name == '>' || *name == ':') + return false; + if (*name == '"' || *name == '|' || *name == '?') + return false; + if (*name == '*' || *name <= 31) + return false; + } #endif ++name; -- cgit v1.2.3