binfmt.c 5.63 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

/***
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <stdlib.h>
#include <stdbool.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>
#include <stdarg.h>
#include <getopt.h>

#include "log.h"
#include "hashmap.h"
#include "strv.h"
#include "util.h"
#include "conf-files.h"
#include "fileio.h"
37
#include "build.h"
38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88

static const char conf_file_dirs[] =
        "/etc/binfmt.d\0"
        "/run/binfmt.d\0"
        "/usr/local/lib/binfmt.d\0"
        "/usr/lib/binfmt.d\0"
#ifdef HAVE_SPLIT_USR
        "/lib/binfmt.d\0"
#endif
        ;

static int delete_rule(const char *rule) {
        _cleanup_free_ char *x = NULL, *fn = NULL;
        char *e;

        assert(rule[0]);

        x = strdup(rule);
        if (!x)
                return log_oom();

        e = strchrnul(x+1, x[0]);
        *e = 0;

        fn = strappend("/proc/sys/fs/binfmt_misc/", x+1);
        if (!fn)
                return log_oom();

        return write_string_file(fn, "-1");
}

static int apply_rule(const char *rule) {
        int r;

        delete_rule(rule);

        r = write_string_file("/proc/sys/fs/binfmt_misc/register", rule);
        if (r < 0) {
                log_error("Failed to add binary format: %s", strerror(-r));
                return r;
        }

        return 0;
}

static int apply_file(const char *path, bool ignore_enoent) {
        _cleanup_fclose_ FILE *f = NULL;
        int r;

        assert(path);

89
        r = search_and_fopen_nulstr(path, "re", NULL, conf_file_dirs, &f);
90 91 92 93 94 95 96 97
        if (r < 0) {
                if (ignore_enoent && r == -ENOENT)
                        return 0;

                log_error("Failed to open file '%s', ignoring: %s", path, strerror(-r));
                return r;
        }

98
        log_debug("apply: %s", path);
99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128
        for (;;) {
                char l[LINE_MAX], *p;
                int k;

                if (!fgets(l, sizeof(l), f)) {
                        if (feof(f))
                                break;

                        log_error("Failed to read file '%s', ignoring: %m", path);
                        return -errno;
                }

                p = strstrip(l);
                if (!*p)
                        continue;
                if (strchr(COMMENTS "\n", *p))
                        continue;

                k = apply_rule(p);
                if (k < 0 && r == 0)
                        r = k;
        }

        return r;
}

static int help(void) {

        printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
               "Registers binary formats.\n\n"
129 130
               "  -h --help             Show this help\n"
               "     --version          Show package version\n",
131 132 133 134 135 136 137
               program_invocation_short_name);

        return 0;
}

static int parse_argv(int argc, char *argv[]) {

138 139 140 141
        enum {
                ARG_VERSION = 0x100,
        };

142 143
        static const struct option options[] = {
                { "help",      no_argument,       NULL, 'h'           },
144 145
                { "version",   no_argument,       NULL, ARG_VERSION   },
                {}
146 147 148 149 150 151 152 153 154 155 156 157
        };

        int c;

        assert(argc >= 0);
        assert(argv);

        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {

                switch (c) {

                case 'h':
158 159 160 161 162
                        return help();

                case ARG_VERSION:
                        puts(PACKAGE_STRING);
                        puts(SYSTEMD_FEATURES);
163 164 165 166 167 168
                        return 0;

                case '?':
                        return -EINVAL;

                default:
169
                        assert_not_reached("Unhandled option");
170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221
                }
        }

        return 1;
}

int main(int argc, char *argv[]) {
        int r, k;

        r = parse_argv(argc, argv);
        if (r <= 0)
                return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;

        log_set_target(LOG_TARGET_AUTO);
        log_parse_environment();
        log_open();

        umask(0022);

        r = 0;

        if (argc > optind) {
                int i;

                for (i = optind; i < argc; i++) {
                        k = apply_file(argv[i], false);
                        if (k < 0 && r == 0)
                                r = k;
                }
        } else {
                _cleanup_strv_free_ char **files = NULL;
                char **f;

                r = conf_files_list_nulstr(&files, ".conf", NULL, conf_file_dirs);
                if (r < 0) {
                        log_error("Failed to enumerate binfmt.d files: %s", strerror(-r));
                        goto finish;
                }

                /* Flush out all rules */
                write_string_file("/proc/sys/fs/binfmt_misc/status", "-1");

                STRV_FOREACH(f, files) {
                        k = apply_file(*f, true);
                        if (k < 0 && r == 0)
                                r = k;
                }
        }

finish:
        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}