include.c

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Author : Pierre Le Marre
Date : 2023-11-06 21:53:51
Hash : 00e3058e
Message : Prevent recursive includes of keymap components - Add check for recursive includes of keymap components. It relies on limiting the include depth. The threshold is currently to 15, which seems reasonable with plenty of margin for keymaps in the wild. - Add corresponding new log message `recursive-include`. - Add tests for recursive includes.
src/xkbcomp/include.c
/************************************************************
 * Copyright (c) 1994 by Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting
 * documentation, and that the name of Silicon Graphics not be
 * used in advertising or publicity pertaining to distribution
 * of the software without specific prior written permission.
 * Silicon Graphics makes no representation about the suitability
 * of this software for any purpose. It is provided "as is"
 * without any express or implied warranty.
 *
 * SILICON GRAPHICS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
 * GRAPHICS BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION  WITH
 * THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 ********************************************************/

/*
 * Copyright © 2012 Ran Benita <ran234@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include "config.h"

#include <errno.h>
#include <limits.h>
#include <stdio.h>

#include "xkbcomp-priv.h"
#include "include.h"

/**
 * Parse an include statement. Each call returns a file name, along with
 * (possibly) a specific map in the file, an explicit group designator, and
 * the separator from the next file, used to determine the merge mode.
 *
 * @param str_inout Input statement, modified in-place. Should be passed in
 * repeatedly. If str_inout is NULL, the parsing has completed.
 *
 * @param file_rtrn Set to the name of the include file to be used. Combined
 * with an enum xkb_file_type, this determines which file to look for in the
 * include path.
 *
 * @param map_rtrn Set to the string between '(' and ')', if any. This will
 * result in the compilation of a specific named map within the file (e.g.
 * xkb_symbols "basic" { ... }) , as opposed to the default map of the file.
 *
 * @param nextop_rtrn Set to the next operation in the complete statement,
 * which is '\0' if it's the last file or '+' or '|' if there are more.
 * Separating the files with '+' sets the merge mode to MERGE_MODE_OVERRIDE,
 * while '|' sets the merge mode to MERGE_MODE_AUGMENT.
 *
 * @param extra_data Set to the string after ':', if any. Currently the
 * extra data is only used for setting an explicit group index for a symbols
 * file.
 *
 * @return true if parsing was successful, false for an illegal string.
 *
 * Example: "evdev+aliases(qwerty):2"
 *      str_inout = "aliases(qwerty):2"
 *      file_rtrn = "evdev"
 *      map_rtrn = NULL
 *      nextop_retrn = "+"
 *      extra_data = NULL
 *
 * 2nd run with "aliases(qwerty):2"
 *      str_inout = NULL
 *      file_rtrn = "aliases"
 *      map_rtrn = "qwerty"
 *      nextop_retrn = ""
 *      extra_data = "2"
 *
 */
bool
ParseIncludeMap(char **str_inout, char **file_rtrn, char **map_rtrn,
                char *nextop_rtrn, char **extra_data)
{
    char *tmp, *str, *next;

    str = *str_inout;

    /*
     * Find the position in the string where the next file is included,
     * if there is more than one left in the statement.
     */
    next = strpbrk(str, "|+");
    if (next) {
        /* Got more files, this function will be called again. */
        *nextop_rtrn = *next;
        /* Separate the string, for strchr etc. to work on this file only. */
        *next++ = '\0';
    }
    else {
        /* This is the last file in this statement, won't be called again. */
        *nextop_rtrn = '\0';
        next = NULL;
    }

    /*
     * Search for the explicit group designator, if any. If it's there,
     * it goes after the file name and map.
     */
    tmp = strchr(str, ':');
    if (tmp != NULL) {
        *tmp++ = '\0';
        *extra_data = strdup(tmp);
    }
    else {
        *extra_data = NULL;
    }

    /* Look for a map, if any. */
    tmp = strchr(str, '(');
    if (tmp == NULL) {
        /* No map. */
        *file_rtrn = strdup(str);
        *map_rtrn = NULL;
    }
    else if (str[0] == '(') {
        /* Map without file - invalid. */
        free(*extra_data);
        return false;
    }
    else {
        /* Got a map; separate the file and the map for the strdup's. */
        *tmp++ = '\0';
        *file_rtrn = strdup(str);
        str = tmp;
        tmp = strchr(str, ')');
        if (tmp == NULL || tmp[1] != '\0') {
            free(*file_rtrn);
            free(*extra_data);
            return false;
        }
        *tmp++ = '\0';
        *map_rtrn = strdup(str);
    }

    /* Set up the next file for the next call, if any. */
    if (*nextop_rtrn == '\0')
        *str_inout = NULL;
    else if (*nextop_rtrn == '|' || *nextop_rtrn == '+')
        *str_inout = next;
    else
        return false;

    return true;
}

static const char *xkb_file_type_include_dirs[_FILE_TYPE_NUM_ENTRIES] = {
    [FILE_TYPE_KEYCODES] = "keycodes",
    [FILE_TYPE_TYPES] = "types",
    [FILE_TYPE_COMPAT] = "compat",
    [FILE_TYPE_SYMBOLS] = "symbols",
    [FILE_TYPE_GEOMETRY] = "geometry",
    [FILE_TYPE_KEYMAP] = "keymap",
    [FILE_TYPE_RULES] = "rules",
};

/**
 * Return the xkb directory based on the type.
 */
static const char *
DirectoryForInclude(enum xkb_file_type type)
{
    if (type >= _FILE_TYPE_NUM_ENTRIES)
        return "";
    return xkb_file_type_include_dirs[type];
}

static void
LogIncludePaths(struct xkb_context *ctx)
{
    unsigned int i;

    if (xkb_context_num_include_paths(ctx) > 0) {
        log_err(ctx,
                XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                "%d include paths searched:\n",
                xkb_context_num_include_paths(ctx));
        for (i = 0; i < xkb_context_num_include_paths(ctx); i++)
            log_err(ctx,
                    XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                    "\t%s\n",
                    xkb_context_include_path_get(ctx, i));
    }
    else {
        log_err(ctx,
                XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                "There are no include paths to search\n");
    }

    if (xkb_context_num_failed_include_paths(ctx) > 0) {
        log_err(ctx,
                XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                "%d include paths could not be added:\n",
                xkb_context_num_failed_include_paths(ctx));
        for (i = 0; i < xkb_context_num_failed_include_paths(ctx); i++)
            log_err(ctx,
                    XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                    "\t%s\n",
                    xkb_context_failed_include_path_get(ctx, i));
    }
}

/**
 * Return an open file handle to the first file (counting from offset) with the
 * given name in the include paths, starting at the offset.
 *
 * offset must be zero the first time this is called and is set to the index the
 * file was found. Call again with offset+1 to keep searching through the
 * include paths.
 *
 * If this function returns NULL, no more files are available.
 */
FILE *
FindFileInXkbPath(struct xkb_context *ctx, const char *name,
                  enum xkb_file_type type, char **pathRtrn,
                  unsigned int *offset)
{
    unsigned int i;
    FILE *file = NULL;
    char buf[PATH_MAX];
    const char *typeDir;

    typeDir = DirectoryForInclude(type);

    for (i = *offset; i < xkb_context_num_include_paths(ctx); i++) {
        if (!snprintf_safe(buf, sizeof(buf), "%s/%s/%s",
                           xkb_context_include_path_get(ctx, i),
                           typeDir, name)) {
            log_err(ctx,
                    XKB_ERROR_INSUFFICIENT_BUFFER_SIZE,
                    "Path is too long: expected max length of %lu, got: %s/%s/%s\n",
                    (unsigned long int) sizeof(buf),
                    xkb_context_include_path_get(ctx, i), typeDir, name);
            continue;
        }

        file = fopen(buf, "rb");
        if (file) {
            if (pathRtrn)
                *pathRtrn = strdup(buf);
            *offset = i;
            goto out;
        }
    }

    /* We only print warnings if we can't find the file on the first lookup */
    if (*offset == 0) {
        log_err(ctx,
                XKB_ERROR_INCLUDED_FILE_NOT_FOUND,
                "Couldn't find file \"%s/%s\" in include paths\n",
                typeDir, name);
        LogIncludePaths(ctx);
    }

out:
    return file;
}

bool
ExceedsIncludeMaxDepth(struct xkb_context *ctx, unsigned int include_depth)
{
    if (include_depth >= INCLUDE_MAX_DEPTH) {
        log_err(ctx,
                XKB_ERROR_RECURSIVE_INCLUDE,
                "Exceeded include depth threshold (%d)",
                INCLUDE_MAX_DEPTH);
        return true;
    } else {
        return false;
    }
}

XkbFile *
ProcessIncludeFile(struct xkb_context *ctx, IncludeStmt *stmt,
                   enum xkb_file_type file_type)
{
    FILE *file;
    XkbFile *xkb_file = NULL;
    unsigned int offset = 0;

    file = FindFileInXkbPath(ctx, stmt->file, file_type, NULL, &offset);
    if (!file)
        return NULL;

    while (file) {
        xkb_file = XkbParseFile(ctx, file, stmt->file, stmt->map);
        fclose(file);

        if (xkb_file) {
            if (xkb_file->file_type != file_type) {
                log_err(ctx,
                        XKB_ERROR_INVALID_INCLUDED_FILE,
                        "Include file of wrong type (expected %s, got %s); "
                        "Include file \"%s\" ignored\n",
                        xkb_file_type_to_string(file_type),
                        xkb_file_type_to_string(xkb_file->file_type), stmt->file);
                FreeXkbFile(xkb_file);
                xkb_file = NULL;
            } else {
                break;
            }
        }

        offset++;
        file = FindFileInXkbPath(ctx, stmt->file, file_type, NULL, &offset);
    }

    if (!xkb_file) {
        if (stmt->map)
            log_err(ctx,
                    XKB_ERROR_INVALID_INCLUDED_FILE,
                    "Couldn't process include statement for '%s(%s)'\n",
                    stmt->file, stmt->map);
        else
            log_err(ctx,
                    XKB_ERROR_INVALID_INCLUDED_FILE,
                    "Couldn't process include statement for '%s'\n",
                    stmt->file);
    }

    return xkb_file;
}
kc3-lang/libxkbcommon/src/xkbcomp/include.c

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kc3-lang/libxkbcommon /src/xkbcomp/include.c
