path: root/src/pacman/check.c

/*
 *  check.c
 *
 *  Copyright (c) 2012-2017 Pacman Development Team <pacman-dev@archlinux.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

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

/* pacman */
#include "check.h"
#include "conf.h"
#include "util.h"

static int check_file_exists(const char *pkgname, char *filepath, size_t rootlen,
                struct stat *st)
{
        /* use lstat to prevent errors from symlinks */
        if(llstat(filepath, st) != 0) {
                if(alpm_option_match_noextract(config->handle, filepath + rootlen) == 0) {
                        /* NoExtract */
                        return -1;
                } else {
                        if(config->quiet) {
                                printf("%s %s\n", pkgname, filepath);
                        } else {
                                pm_printf(ALPM_LOG_WARNING, "%s: %s (%s)\n",
                                                pkgname, filepath, strerror(errno));
                        }
                        return 1;
                }
        }

        return 0;
}

static int check_file_type(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry)
{
        mode_t archive_type = archive_entry_filetype(entry);
        mode_t file_type = st->st_mode;

        if((archive_type == AE_IFREG && !S_ISREG(file_type)) ||
                        (archive_type == AE_IFDIR && !S_ISDIR(file_type)) ||
                        (archive_type == AE_IFLNK && !S_ISLNK(file_type))) {
                if(config->quiet) {
                        printf("%s %s\n", pkgname, filepath);
                } else {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (File type mismatch)\n"),
                                        pkgname, filepath);
                }
                return 1;
        }

        return 0;
}

static int check_file_permissions(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry)
{
        int errors = 0;
        mode_t fsmode;

        /* uid */
        if(st->st_uid != archive_entry_uid(entry)) {
                errors++;
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (UID mismatch)\n"),
                                        pkgname, filepath);
                }
        }

        /* gid */
        if(st->st_gid != archive_entry_gid(entry)) {
                errors++;
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (GID mismatch)\n"),
                                        pkgname, filepath);
                }
        }

        /* mode */
        fsmode = st->st_mode & (S_ISUID | S_ISGID | S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO);
        if(fsmode != (~AE_IFMT & archive_entry_mode(entry))) {
                errors++;
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (Permissions mismatch)\n"),
                                        pkgname, filepath);
                }
        }

        return (errors != 0 ? 1 : 0);
}

static int check_file_time(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry, int backup)
{
        if(st->st_mtime != archive_entry_mtime(entry)) {
                if(backup) {
                        if(!config->quiet) {
                                printf("%s%s%s: ", config->colstr.title, _("backup file"),
                                                config->colstr.nocolor);
                                printf(_("%s: %s (Modification time mismatch)\n"),
                                                pkgname, filepath);
                        }
                        return 0;
                }
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (Modification time mismatch)\n"),
                                        pkgname, filepath);
                }
                return 1;
        }

        return 0;
}

static int check_file_link(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry)
{
        size_t length = st->st_size + 1;
        char link[length];

        if(readlink(filepath, link, length) != st->st_size) {
                /* this should not happen */
                pm_printf(ALPM_LOG_ERROR, _("unable to read symlink contents: %s\n"), filepath);
                return 1;
        }
        link[length - 1] = '\0';

        if(strcmp(link, archive_entry_symlink(entry)) != 0) {
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (Symlink path mismatch)\n"),
                                        pkgname, filepath);
                }
                return 1;
        }

        return 0;
}

static int check_file_size(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry, int backup)
{
        if(st->st_size != archive_entry_size(entry)) {
                if(backup) {
                        if(!config->quiet) {
                                printf("%s%s%s: ", config->colstr.title, _("backup file"),
                                                config->colstr.nocolor);
                                printf(_("%s: %s (Size mismatch)\n"),
                                                pkgname, filepath);
                        }
                        return 0;
                }
                if(!config->quiet) {
                        pm_printf(ALPM_LOG_WARNING, _("%s: %s (Size mismatch)\n"),
                                        pkgname, filepath);
                }
                return 1;
        }

        return 0;
}

/* placeholders - libarchive currently does not read checksums from mtree files
static int check_file_md5sum(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry, int backup)
{
        return 0;
}

static int check_file_sha256sum(const char *pkgname, const char *filepath,
                struct stat *st, struct archive_entry *entry, int backup)
{
        return 0;
}
*/

/* Loop through the files of the package to check if they exist. */
int check_pkg_fast(alpm_pkg_t *pkg)
{
        const char *root, *pkgname;
        size_t errors = 0;
        size_t rootlen;
        char filepath[PATH_MAX];
        alpm_filelist_t *filelist;
        size_t i;

        root = alpm_option_get_root(config->handle);
        rootlen = strlen(root);
        if(rootlen + 1 > PATH_MAX) {
                /* we are in trouble here */
                pm_printf(ALPM_LOG_ERROR, _("path too long: %s%s\n"), root, "");
                return 1;
        }
        strcpy(filepath, root);

        pkgname = alpm_pkg_get_name(pkg);
        filelist = alpm_pkg_get_files(pkg);
        for(i = 0; i < filelist->count; i++) {
                const alpm_file_t *file = filelist->files + i;
                struct stat st;
                int exists;
                const char *path = file->name;
                size_t plen = strlen(path);

                if(rootlen + 1 + plen > PATH_MAX) {
                        pm_printf(ALPM_LOG_WARNING, _("path too long: %s%s\n"), root, path);
                        continue;
                }
                strcpy(filepath + rootlen, path);

                exists = check_file_exists(pkgname, filepath, rootlen, &st);
                if(exists == 0) {
                        int expect_dir = path[plen - 1] == '/' ? 1 : 0;
                        int is_dir = S_ISDIR(st.st_mode) ? 1 : 0;
                        if(expect_dir != is_dir) {
                                pm_printf(ALPM_LOG_WARNING, _("%s: %s (File type mismatch)\n"),
                                                pkgname, filepath);
                                ++errors;
                        }
                } else if(exists == 1) {
                        ++errors;
                }
        }

        if(!config->quiet) {
                printf(_n("%s: %jd total file, ", "%s: %jd total files, ",
                                        (unsigned long)filelist->count), pkgname, (intmax_t)filelist->count);
                printf(_n("%jd missing file\n", "%jd missing files\n",
                                        (unsigned long)errors), (intmax_t)errors);
        }

        return (errors != 0 ? 1 : 0);
}

/* Loop though files in a package and perform full file property checking. */
int check_pkg_full(alpm_pkg_t *pkg)
{
        const char *root, *pkgname;
        size_t errors = 0;
        size_t rootlen;
        struct archive *mtree;
        struct archive_entry *entry = NULL;
        size_t file_count = 0;
        const alpm_list_t *lp;

        root = alpm_option_get_root(config->handle);
        rootlen = strlen(root);
        if(rootlen + 1 > PATH_MAX) {
                /* we are in trouble here */
                pm_printf(ALPM_LOG_ERROR, _("path too long: %s%s\n"), root, "");
                return 1;
        }

        pkgname = alpm_pkg_get_name(pkg);
        mtree = alpm_pkg_mtree_open(pkg);
        if(mtree == NULL) {
                /* TODO: check error to confirm failure due to no mtree file */
                if(!config->quiet) {
                        printf(_("%s: no mtree file\n"), pkgname);
                }
                return 0;
        }

        while(alpm_pkg_mtree_next(pkg, mtree, &entry) == ARCHIVE_OK) {
                struct stat st;
                const char *path = archive_entry_pathname(entry);
                char filepath[PATH_MAX];
                int filepath_len;
                mode_t type;
                size_t file_errors = 0;
                int backup = 0;
                int exists;

                /* strip leading "./" from path entries */
                if(path[0] == '.' && path[1] == '/') {
                        path += 2;
                }

                if(*path == '.') {
                        const char *dbfile = NULL;

                        if(strcmp(path, ".INSTALL") == 0) {
                                dbfile = "install";
                        } else if(strcmp(path, ".CHANGELOG") == 0) {
                                dbfile = "changelog";
                        } else {
                                continue;
                        }

                        /* Do not append root directory as alpm_option_get_dbpath is already
                         * an absoute path */
                        filepath_len = snprintf(filepath, PATH_MAX, "%slocal/%s-%s/%s",
                                        alpm_option_get_dbpath(config->handle),
                                        pkgname, alpm_pkg_get_version(pkg), dbfile);
                        if(filepath_len >= PATH_MAX) {
                                pm_printf(ALPM_LOG_WARNING, _("path too long: %slocal/%s-%s/%s\n"),
                                                alpm_option_get_dbpath(config->handle),
                                                pkgname, alpm_pkg_get_version(pkg), dbfile);
                                continue;
                        }
                } else {
                        filepath_len = snprintf(filepath, PATH_MAX, "%s%s", root, path);
                        if(filepath_len >= PATH_MAX) {
                                pm_printf(ALPM_LOG_WARNING, _("path too long: %s%s\n"), root, path);
                                continue;
                        }
                }

                file_count++;

                exists = check_file_exists(pkgname, filepath, rootlen, &st);
                if(exists == 1) {
                        errors++;
                        continue;
                } else if(exists == -1) {
                        /* NoExtract */
                        continue;
                }

                type = archive_entry_filetype(entry);

                if(type != AE_IFDIR && type != AE_IFREG && type != AE_IFLNK) {
                        pm_printf(ALPM_LOG_WARNING, _("file type not recognized: %s%s\n"), root, path);
                        continue;
                }

                if(check_file_type(pkgname, filepath, &st, entry) == 1) {
                        errors++;
                        continue;
                }

                file_errors += check_file_permissions(pkgname, filepath, &st, entry);

                if(type == AE_IFLNK) {
                        file_errors += check_file_link(pkgname, filepath, &st, entry);
                }

                /* the following checks are expected to fail if a backup file has been
                   modified */
                for(lp = alpm_pkg_get_backup(pkg); lp; lp = lp->next) {
                        alpm_backup_t *bl = lp->data;

                        if(strcmp(path, bl->name) == 0) {
                                backup = 1;
                                break;
                        }
                }

                if(type != AE_IFDIR) {
                        /* file or symbolic link */
                        file_errors += check_file_time(pkgname, filepath, &st, entry, backup);
                }

                if(type == AE_IFREG) {
                        file_errors += check_file_size(pkgname, filepath, &st, entry, backup);
                        /* file_errors += check_file_md5sum(pkgname, filepath, &st, entry, backup); */
                }

                if(config->quiet && file_errors) {
                        printf("%s %s\n", pkgname, filepath);
                }

                errors += (file_errors != 0 ? 1 : 0);
        }

        alpm_pkg_mtree_close(pkg, mtree);

        if(!config->quiet) {
                printf(_n("%s: %jd total file, ", "%s: %jd total files, ",
                                        (unsigned long)file_count), pkgname, (intmax_t)file_count);
                printf(_n("%jd altered file\n", "%jd altered files\n",
                                        (unsigned long)errors), (intmax_t)errors);
        }

        return (errors != 0 ? 1 : 0);
}

/* vim: set noet: */