diff options
Diffstat (limited to 'src/extras/edd_id/edd_id.c')
| -rw-r--r-- | src/extras/edd_id/edd_id.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/src/extras/edd_id/edd_id.c b/src/extras/edd_id/edd_id.c new file mode 100644 index 0000000000..ac4da07611 --- /dev/null +++ b/src/extras/edd_id/edd_id.c @@ -0,0 +1,196 @@ +/* + * edd_id - naming of BIOS disk devices via EDD + * + * Copyright (C) 2005 John Hull <John_Hull@Dell.com> + * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.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/>. + */ + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE 1 +#endif + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <fcntl.h> +#include <ctype.h> +#include <string.h> +#include <errno.h> +#include <dirent.h> +#include <stdint.h> + +#include "libudev.h" +#include "libudev-private.h" + +static void log_fn(struct udev *udev, int priority, + const char *file, int line, const char *fn, + const char *format, va_list args) +{ + vsyslog(priority, format, args); +} + +int main(int argc, char *argv[]) +{ + struct udev *udev; + const char *node = NULL; + int i; + int export = 0; + uint32_t disk_id; + uint16_t mbr_valid; + struct dirent *dent; + int disk_fd; + int sysfs_fd; + DIR *dir = NULL; + int rc = 1; + char filename[UTIL_PATH_SIZE]; + char match[UTIL_PATH_SIZE]; + + udev = udev_new(); + if (udev == NULL) + goto exit; + + udev_log_init("edd_id"); + udev_set_log_fn(udev, log_fn); + + for (i = 1 ; i < argc; i++) { + char *arg = argv[i]; + + if (strcmp(arg, "--export") == 0) { + export = 1; + } else + node = arg; + } + if (node == NULL) { + err(udev, "no node specified\n"); + fprintf(stderr, "no node specified\n"); + goto exit; + } + + /* check for kernel support */ + util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev), "/firmware/edd", NULL); + dir = opendir(filename); + if (dir == NULL) { + info(udev, "no kernel EDD support\n"); + fprintf(stderr, "no kernel EDD support\n"); + rc = 2; + goto exit; + } + + disk_fd = open(node, O_RDONLY); + if (disk_fd < 0) { + info(udev, "unable to open '%s'\n", node); + fprintf(stderr, "unable to open '%s'\n", node); + rc = 3; + goto closedir; + } + + /* check for valid MBR signature */ + if (lseek(disk_fd, 510, SEEK_SET) < 0) { + info(udev, "seek to MBR validity failed '%s'\n", node); + rc = 4; + goto close; + } + if (read(disk_fd, &mbr_valid, sizeof(mbr_valid)) != sizeof(mbr_valid)) { + info(udev, "read MBR validity failed '%s'\n", node); + rc = 5; + goto close; + } + if (mbr_valid != 0xAA55) { + fprintf(stderr, "no valid MBR signature '%s'\n", node); + info(udev, "no valid MBR signature '%s'\n", node); + rc=6; + goto close; + } + + /* read EDD signature */ + if (lseek(disk_fd, 440, SEEK_SET) < 0) { + info(udev, "seek to signature failed '%s'\n", node); + rc = 7; + goto close; + } + if (read(disk_fd, &disk_id, sizeof(disk_id)) != sizeof(disk_id)) { + info(udev, "read signature failed '%s'\n", node); + rc = 8; + goto close; + } + /* all zero is invalid */ + info(udev, "read id 0x%08x from '%s'\n", disk_id, node); + if (disk_id == 0) { + fprintf(stderr, "no EDD signature '%s'\n", node); + info(udev, "'%s' signature is zero\n", node); + rc = 9; + goto close; + } + + /* lookup signature in sysfs to determine the name */ + match[0] = '\0'; + for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) { + char sysfs_id_buf[256]; + uint32_t sysfs_id; + ssize_t size; + + if (dent->d_name[0] == '.') + continue; + + util_strscpyl(filename, sizeof(filename), dent->d_name, "/mbr_signature", NULL); + sysfs_fd = openat(dirfd(dir), filename, O_RDONLY); + if (sysfs_fd < 0) { + info(udev, "unable to open sysfs '%s'\n", filename); + continue; + } + + size = read(sysfs_fd, sysfs_id_buf, sizeof(sysfs_id_buf)-1); + close(sysfs_fd); + if (size <= 0) { + info(udev, "read sysfs '%s' failed\n", filename); + continue; + } + sysfs_id_buf[size] = '\0'; + info(udev, "read '%s' from '%s'\n", sysfs_id_buf, filename); + sysfs_id = strtoul(sysfs_id_buf, NULL, 16); + + /* look for matching value, that appears only once */ + if (disk_id == sysfs_id) { + if (match[0] == '\0') { + /* store id */ + util_strscpy(match, sizeof(match), dent->d_name); + } else { + /* error, same signature for another device */ + info(udev, "'%s' does not have a unique signature\n", node); + fprintf(stderr, "'%s' does not have a unique signature\n", node); + rc = 10; + goto exit; + } + } + } + + if (match[0] != '\0') { + if (export) + printf("ID_EDD=%s\n", match); + else + printf("%s\n", match); + rc = 0; + } + +close: + close(disk_fd); +closedir: + closedir(dir); +exit: + udev_unref(udev); + udev_log_close(); + return rc; +} |