in src/common-ssh/sftp.c [37:103]
int guac_common_ssh_sftp_normalize_path(char* fullpath,
const char* path) {
int path_depth = 0;
const char* path_components[GUAC_COMMON_SSH_SFTP_MAX_DEPTH];
/* If original path is not absolute, normalization fails */
if (path[0] != '\\' && path[0] != '/')
return 0;
/* Create scratch copy of path excluding leading slash (we will be
* replacing path separators with null terminators and referencing those
* substrings directly as path components) */
char path_scratch[GUAC_COMMON_SSH_SFTP_MAX_PATH - 1];
int length = guac_strlcpy(path_scratch, path + 1,
sizeof(path_scratch));
/* Fail if provided path is too long */
if (length >= sizeof(path_scratch))
return 0;
/* Locate all path components within path */
const char* current_path_component = &(path_scratch[0]);
for (int i = 0; i <= length; i++) {
/* If current character is a path separator, parse as component */
char c = path_scratch[i];
if (c == '/' || c == '\\' || c == '\0') {
/* Terminate current component */
path_scratch[i] = '\0';
/* If component refers to parent, just move up in depth */
if (strcmp(current_path_component, "..") == 0) {
if (path_depth > 0)
path_depth--;
}
/* Otherwise, if component not current directory, add to list */
else if (strcmp(current_path_component, ".") != 0
&& strcmp(current_path_component, "") != 0) {
/* Fail normalization if path is too deep */
if (path_depth >= GUAC_COMMON_SSH_SFTP_MAX_DEPTH)
return 0;
path_components[path_depth++] = current_path_component;
}
/* Update start of next component */
current_path_component = &(path_scratch[i+1]);
} /* end if separator */
} /* end for each character */
/* Add leading slash for resulting absolute path */
fullpath[0] = '/';
/* Append normalized components to path, separated by slashes */
guac_strljoin(fullpath + 1, path_components, path_depth,
"/", GUAC_COMMON_SSH_SFTP_MAX_PATH - 1);
return 1;
}