util-path.c

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/* Copyright (C) 2007-2023 Open Information Security Foundation
 *
 * You can copy, redistribute or modify this Program under the terms of
 * the GNU General Public License version 2 as published by the Free
 * Software Foundation.
 *
 * 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
 * version 2 along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */
 
/**
 * \file
 *
 * \author Victor Julien <victor@inliniac.net>
 *
 */
 
#include "suricata-common.h"
#include "suricata.h"
#include "util-debug.h"
#include "util-path.h"
 
#ifdef OS_WIN32
#include "win32-misc.h"
#define DIRECTORY_SEPARATOR '\\'
#else
#define DIRECTORY_SEPARATOR '/'
#endif
 
/**
 *  \brief Check if a path is absolute
 *
 *  \param path string with the path
 *
 *  \retval 1 absolute
 *  \retval 0 not absolute
 */
int PathIsAbsolute(const char *path)
{
    if (strlen(path) > 1 && path[0] == '/') {
        return 1;
    }
 
#if (defined OS_WIN32 || defined __CYGWIN__)
    if (strlen(path) > 2) {
        if (isalpha((unsigned char)path[0]) && path[1] == ':') {
            return 1;
        }
    }
#endif
 
    return 0;
}
 
/**
 *  \brief Check if a path is relative
 *
 *  \param path string with the path
 *
 *  \retval 1 relative
 *  \retval 0 not relative
 */
int PathIsRelative(const char *path)
{
    return PathIsAbsolute(path) ? 0 : 1;
}
 
int PathMerge(char *out_buf, size_t buf_size, const char *const dir, const char *const fname)
{
    char path[PATH_MAX];
    if (dir == NULL || strlen(dir) == 0)
        return -1;
 
    size_t r = strlcpy(path, dir, sizeof(path));
    if (r >= sizeof(path)) {
        return -1;
    }
 
#if defined OS_WIN32 || defined __CYGWIN__
    if (path[strlen(path) - 1] != '\\')
        r = strlcat(path, "\\\\", sizeof(path));
#else
    if (path[strlen(path) - 1] != '/')
        r = strlcat(path, "/", sizeof(path));
#endif
    if (r >= sizeof(path)) {
        return -1;
    }
    r = strlcat(path, fname, sizeof(path));
    if (r >= sizeof(path)) {
        return -1;
    }
    r = strlcpy(out_buf, path, buf_size);
    if (r >= buf_size) {
        return -1;
    }
 
    return 0;
}
 
char *PathMergeAlloc(const char *const dir, const char *const fname)
{
    char path[PATH_MAX];
    if (PathMerge(path, sizeof(path), dir, fname) != 0)
        return NULL;
 
    char *ret = SCStrdup(path);
    if (ret == NULL)
        return NULL;
 
    return ret;
}
 
/**
 * \brief Wrapper around SCMkDir with default mode arguments.
 */
int SCDefaultMkDir(const char *path)
{
    return SCMkDir(path, S_IRWXU | S_IRGRP | S_IXGRP);
}
 
/**
 * \brief Recursively create a directory.
 *
 * \param path Path to create
 * \param final true will create the final path component, false will not
 *
 * \retval 0 on success
 * \retval -1 on error
 */
int SCCreateDirectoryTree(const char *path, const bool final)
{
    char pathbuf[PATH_MAX];
    char *p;
    size_t len = strlen(path);
 
    if (len > PATH_MAX - 1) {
        return -1;
    }
 
    strlcpy(pathbuf, path, sizeof(pathbuf));
 
    for (p = pathbuf + 1; *p; p++) {
        if (*p == '/') {
            /* Truncate, while creating directory */
            *p = '\0';
 
            if (SCDefaultMkDir(pathbuf) != 0) {
                if (errno != EEXIST) {
                    return -1;
                }
            }
 
            *p = '/';
        }
    }
 
    if (final) {
        if (SCDefaultMkDir(pathbuf) != 0) {
            if (errno != EEXIST) {
                return -1;
            }
        }
    }
 
    return 0;
}
 
/**
 * \brief Check if a path exists.
 *
 * \param Path to check for existence
 *
 * \retval true if path exists
 * \retval false if path does not exist
 */
bool SCPathExists(const char *path)
{
    struct stat sb;
    return stat(path, &sb) == 0;
}
 
/**
 * \brief OS independent wrapper for directory check
 *
 * \param dir_entry object to check
 *
 * \retval True if the object is a regular directory, otherwise false.  This directory
 *          and parent directory will return false.
 */
bool SCIsRegularDirectory(const struct dirent *const dir_entry)
{
#if !defined(OS_WIN32) && !defined(__sun)
    if ((dir_entry->d_type == DT_DIR) &&
        (strcmp(dir_entry->d_name, ".") != 0) &&
        (strcmp(dir_entry->d_name, "..") != 0)) {
        return true;
    }
#endif
    return false;
}
/**
 * \brief OS independent to check for regular file
 *
 * \param dir_entry object to check
 *
 * \retval True if the object is a regular file.  Otherwise false.
 */
bool SCIsRegularFile(const struct dirent *const dir_entry)
{
#if defined(DT_REG)
    return dir_entry->d_type == DT_REG;
#endif
    return false;
}
 
/**
 * \brief OS independent wrapper for realpath
 *
 * \param path the path to resolve
 * \param resolved_path the resolved path; if null, a buffer will be allocated
 *
 * \retval the resolved_path; or a pointer to a new resolved_path buffer
 */
char *SCRealPath(const char *path, char *resolved_path)
{
#ifdef OS_WIN32
    return _fullpath(resolved_path, path, PATH_MAX);
#else
    return realpath(path, resolved_path);
#endif
}
 
/*
 * \brief Return the basename of the provided path.
 * \param path The path on which to compute the basename
 *
 * \retval the basename of the path or NULL if the path lacks a non-leaf
 */
const char *SCBasename(const char *path)
{
    if (!path || strlen(path) == 0)
        return NULL;
 
    const char *final = strrchr(path, DIRECTORY_SEPARATOR);
    if (!final)
        return path;
 
    if (*(final + 1) == '\0')
        return NULL;
 
    return final + 1;
}
 
/**
 * \brief Check for directory traversal
 *
 * \param path The path string to check for traversal
 *
 * \retval true if directory traversal is found, otherwise false
 */
bool SCPathContainsTraversal(const char *path)
{
#ifdef OS_WIN32
    /* Win32 treats '/' and '\\' as equivalent directory separators */
    return strstr(path, "../") != NULL || strstr(path, "..\\") != NULL;
#else
    return strstr(path, "../") != NULL;
#endif
}
 
/**
 * \brief Open a text log file for append or truncate.
 *
 * On Windows, allows the file to be renamed or deleted while open so that
 * external tools can rotate it. Only modes "a" and "w" are supported on
 * all platforms; other modes fail with errno set to EINVAL.
 *
 * \param path The file path to open
 * \param mode "a" to append or "w" to truncate
 * \retval FILE* on success
 * \retval NULL on error with errno set
 */
FILE *SCFopenLogFile(const char *path, const char *mode)
{
    if (strcmp(mode, "a") != 0 && strcmp(mode, "w") != 0) {
        errno = EINVAL;
        return NULL;
    }
 
#ifdef OS_WIN32
    return SCWin32Fopen(path, mode);
#else
    return fopen(path, mode);
#endif
}
 
/**
 * \brief Update access and modification time of an existing file to 'now'.
 * \param path The file path to touch
 * \retval 0 on success, -1 on failure
 */
int SCTouchFile(const char *path)
{
    if (path == NULL || path[0] == '\0') {
        errno = EINVAL;
        return -1;
    }
#ifndef OS_WIN32
    struct utimbuf ub;
    ub.actime = ub.modtime = time(NULL);
    if (utime(path, &ub) == 0)
        return 0;
#endif
    return -1;
}