Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame] | 1 | /* |
| 2 | * kernel/configs.c |
| 3 | * Echo the kernel .config file used to build the kernel |
| 4 | * |
| 5 | * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com> |
| 6 | * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net> |
| 7 | * Copyright (C) 2002 Al Stone <ahs3@fc.hp.com> |
| 8 | * Copyright (C) 2002 Hewlett-Packard Company |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation; either version 2 of the License, or (at |
| 13 | * your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, but |
| 16 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 18 | * NON INFRINGEMENT. See the GNU General Public License for more |
| 19 | * details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 24 | */ |
| 25 | |
| 26 | #include <linux/kernel.h> |
| 27 | #include <linux/module.h> |
| 28 | #include <linux/proc_fs.h> |
| 29 | #include <linux/seq_file.h> |
| 30 | #include <linux/init.h> |
| 31 | #include <asm/uaccess.h> |
| 32 | |
| 33 | /**************************************************/ |
| 34 | /* the actual current config file */ |
| 35 | |
| 36 | /* |
| 37 | * Define kernel_config_data and kernel_config_data_size, which contains the |
| 38 | * wrapped and compressed configuration file. The file is first compressed |
| 39 | * with gzip and then bounded by two eight byte magic numbers to allow |
| 40 | * extraction from a binary kernel image: |
| 41 | * |
| 42 | * IKCFG_ST |
| 43 | * <image> |
| 44 | * IKCFG_ED |
| 45 | */ |
| 46 | #define MAGIC_START "IKCFG_ST" |
| 47 | #define MAGIC_END "IKCFG_ED" |
| 48 | #include "config_data.h" |
| 49 | |
| 50 | |
| 51 | #define MAGIC_SIZE (sizeof(MAGIC_START) - 1) |
| 52 | #define kernel_config_data_size \ |
| 53 | (sizeof(kernel_config_data) - 1 - MAGIC_SIZE * 2) |
| 54 | |
| 55 | #ifdef CONFIG_IKCONFIG_PROC |
| 56 | |
| 57 | static ssize_t |
| 58 | ikconfig_read_current(struct file *file, char __user *buf, |
| 59 | size_t len, loff_t * offset) |
| 60 | { |
| 61 | return simple_read_from_buffer(buf, len, offset, |
| 62 | kernel_config_data + MAGIC_SIZE, |
| 63 | kernel_config_data_size); |
| 64 | } |
| 65 | |
| 66 | static const struct file_operations ikconfig_file_ops = { |
| 67 | .owner = THIS_MODULE, |
| 68 | .read = ikconfig_read_current, |
| 69 | .llseek = default_llseek, |
| 70 | }; |
| 71 | |
| 72 | static int __init ikconfig_init(void) |
| 73 | { |
| 74 | struct proc_dir_entry *entry; |
| 75 | |
| 76 | /* create the current config file */ |
| 77 | entry = proc_create("config.gz", S_IFREG | S_IRUGO, NULL, |
| 78 | &ikconfig_file_ops); |
| 79 | if (!entry) |
| 80 | return -ENOMEM; |
| 81 | |
| 82 | proc_set_size(entry, kernel_config_data_size); |
| 83 | |
| 84 | return 0; |
| 85 | } |
| 86 | |
| 87 | static void __exit ikconfig_cleanup(void) |
| 88 | { |
| 89 | remove_proc_entry("config.gz", NULL); |
| 90 | } |
| 91 | |
| 92 | module_init(ikconfig_init); |
| 93 | module_exit(ikconfig_cleanup); |
| 94 | |
| 95 | #endif /* CONFIG_IKCONFIG_PROC */ |
| 96 | |
| 97 | MODULE_LICENSE("GPL"); |
| 98 | MODULE_AUTHOR("Randy Dunlap"); |
| 99 | MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel"); |