| Start/ | End/ | |||
| True | False | - | Line | Source |
| 1 | /* -*- linux-c -*- --------------------------------------------------------- * | |||
| 2 | * | |||
| 3 | * linux/fs/devpts/inode.c | |||
| 4 | * | |||
| 5 | * Copyright 1998-2004 H. Peter Anvin -- All Rights Reserved | |||
| 6 | * | |||
| 7 | * This file is part of the Linux kernel and is made available under | |||
| 8 | * the terms of the GNU General Public License, version 2, or at your | |||
| 9 | * option, any later version, incorporated herein by reference. | |||
| 10 | * | |||
| 11 | * ------------------------------------------------------------------------- */ | |||
| 12 | ||||
| 13 | #include <linux/module.h> | |||
| 14 | #include <linux/init.h> | |||
| 15 | #include <linux/fs.h> | |||
| 16 | #include <linux/sched.h> | |||
| 17 | #include <linux/namei.h> | |||
| 18 | #include <linux/mount.h> | |||
| 19 | #include <linux/tty.h> | |||
| 20 | #include <linux/devpts_fs.h> | |||
| 21 | ||||
| 22 | #define DEVPTS_SUPER_MAGIC 0x1cd1 | |||
| 23 | ||||
| 24 | static struct vfsmount *devpts_mnt; | |||
| 25 | static struct dentry *devpts_root; | |||
| 26 | ||||
| 27 | static struct { | |||
| 28 | int setuid; | |||
| 29 | int setgid; | |||
| 30 | uid_t uid; | |||
| 31 | gid_t gid; | |||
| 32 | umode_t mode; | |||
| 33 | } config = {.mode = 0600}; | |||
| 34 | ||||
| 12 | 0 | 35 | static int devpts_remount(struct super_block *sb, int *flags, char *data) | |
| 36 | { | |||
| 37 | int setuid = 0; | |||
| 38 | int setgid = 0; | |||
| 39 | uid_t uid = 0; | |||
| 40 | gid_t gid = 0; | |||
| 41 | umode_t mode = 0600; | |||
| 42 | char *this_char; | |||
| 43 | ||||
| 44 | this_char = NULL; | |||
| 12 | 12 | 45 | while ((this_char = strsep(&data, ",")) != NULL) { | |
| 46 | int n; | |||
| 47 | char dummy; | |||
| 0 | 12 | - | 48 | if (!*this_char) |
| 0 | - | 49 | continue; | |
| 0 | 12 | - | 50 | if (sscanf(this_char, "uid=%i%c", &n, &dummy) == 1) { |
| 51 | setuid = 1; | |||
| 52 | uid = n; | |||
| 6 | 6 | 53 | } else if (sscanf(this_char, "gid=%i%c", &n, &dummy) == 1) { | |
| 54 | setgid = 1; | |||
| 55 | gid = n; | |||
| 6 | 0 | - | 56 | } else if (sscanf(this_char, "mode=%o%c", &n, &dummy) == 1) |
| 57 | mode = n & ~S_IFMT; | |||
| 58 | else { | |||
| 59 | printk("devpts: called with bogus options\n"); | |||
| 0 | - | 60 | return -EINVAL; | |
| 61 | } | |||
| 62 | } | |||
| 63 | config.setuid = setuid; | |||
| 64 | config.setgid = setgid; | |||
| 65 | config.uid = uid; | |||
| 66 | config.gid = gid; | |||
| 67 | config.mode = mode; | |||
| 68 | ||||
| 12 | 69 | return 0; | ||
| 70 | } | |||
| 71 | ||||
| 72 | static struct super_operations devpts_sops = { | |||
| 73 | .statfs = simple_statfs, | |||
| 74 | .remount_fs = devpts_remount, | |||
| 75 | }; | |||
| 76 | ||||
| 77 | static int | |||
| 6 | 0 | 78 | devpts_fill_super(struct super_block *s, void *data, int silent) | |
| 79 | { | |||
| 80 | struct inode * inode; | |||
| 81 | ||||
| 82 | s->s_blocksize = 1024; | |||
| 83 | s->s_blocksize_bits = 10; | |||
| 84 | s->s_magic = DEVPTS_SUPER_MAGIC; | |||
| 85 | s->s_op = &devpts_sops; | |||
| 86 | s->s_time_gran = 1; | |||
| 87 | ||||
| 88 | inode = new_inode(s); | |||
| 0 | 6 | - | 89 | if (!inode) |
| 0 | - | 90 | goto fail; | |
| 91 | inode->i_ino = 1; | |||
| 92 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |||
| 93 | inode->i_blocks = 0; | |||
| 94 | inode->i_blksize = 1024; | |||
| 95 | inode->i_uid = inode->i_gid = 0; | |||
| 96 | inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR; | |||
| 97 | inode->i_op = &simple_dir_inode_operations; | |||
| 98 | inode->i_fop = &simple_dir_operations; | |||
| 99 | inode->i_nlink = 2; | |||
| 100 | ||||
| 101 | devpts_root = s->s_root = d_alloc_root(inode); | |||
| 6 | 0 | - | 102 | if (s->s_root) |
| 6 | 103 | return 0; | ||
| 104 | ||||
| 105 | printk("devpts: get root dentry failed\n"); | |||
| 106 | iput(inode); | |||
| 107 | fail: | |||
| 0 | - | 108 | return -ENOMEM; | |
| 109 | } | |||
| 110 | ||||
| 12 | 0 | 111 | static struct super_block *devpts_get_sb(struct file_system_type *fs_type, | |
| 112 | int flags, const char *dev_name, void *data) | |||
| 113 | { | |||
| 12 | 114 | return get_sb_single(fs_type, flags, data, devpts_fill_super); | ||
| 115 | } | |||
| 116 | ||||
| 117 | static struct file_system_type devpts_fs_type = { | |||
| 118 | .owner = THIS_MODULE, | |||
| 119 | .name = "devpts", | |||
| 120 | .get_sb = devpts_get_sb, | |||
| 121 | .kill_sb = kill_anon_super, | |||
| 122 | }; | |||
| 123 | ||||
| 124 | /* | |||
| 125 | * The normal naming convention is simply /dev/pts/<number>; this conforms | |||
| 126 | * to the System V naming convention | |||
| 127 | */ | |||
| 128 | ||||
| 2757 | 0 | 129 | static struct dentry *get_node(int num) | |
| 130 | { | |||
| 131 | char s[12]; | |||
| 132 | struct dentry *root = devpts_root; | |||
| 133 | mutex_lock(&root->d_inode->i_mutex); | |||
| 2757 | 134 | return lookup_one_len(s, root, sprintf(s, "%d", num)); | ||
| 135 | } | |||
| 136 | ||||
| 113 | 0 | 137 | int devpts_pty_new(struct tty_struct *tty) | |
| 138 | { | |||
| 139 | int number = tty->index; | |||
| 140 | struct tty_driver *driver = tty->driver; | |||
| 141 | dev_t device = MKDEV(driver->major, driver->minor_start+number); | |||
| 142 | struct dentry *dentry; | |||
| 143 | struct inode *inode = new_inode(devpts_mnt->mnt_sb); | |||
| 144 | ||||
| 145 | /* We're supposed to be given the slave end of a pty */ | |||
| 146 | BUG_ON(driver->type != TTY_DRIVER_TYPE_PTY); | |||
| 0 | 113 | - | 146 | if (__builtin_expect ( ! ! ( ( driver -> typ.. |
| 0 | 113 | - | 146 | do-while (0) |
| 147 | BUG_ON(driver->subtype != PTY_TYPE_SLAVE); | |||
| 0 | 113 | - | 147 | if (__builtin_expect ( ! ! ( ( driver -> sub.. |
| 0 | 113 | - | 147 | do-while (0) |
| 148 | ||||
| 0 | 113 | - | 149 | if (!inode) |
| 0 | - | 150 | return -ENOMEM; | |
| 151 | ||||
| 152 | inode->i_ino = number+2; | |||
| 153 | inode->i_blksize = 1024; | |||
| 154 | inode->i_uid = config.setuid ? config.uid : current->fsuid; | |||
| 0 | 113 | - | 154 | ternary-?: config . setuid |
| 155 | inode->i_gid = config.setgid ? config.gid : current->fsgid; | |||
| 113 | 0 | - | 155 | ternary-?: config . setgid |
| 156 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |||
| 157 | init_special_inode(inode, S_IFCHR|config.mode, device); | |||
| 158 | inode->u.generic_ip = tty; | |||
| 159 | ||||
| 160 | dentry = get_node(number); | |||
| 113 | 0 | - | 161 | if (!IS_ERR(dentry) && !dentry->d_inode) |
| 113 | 161 | T && T | ||
| 0 | - | 161 | T && F | |
| 0 | - | 161 | F && _ | |
| 162 | d_instantiate(dentry, inode); | |||
| 163 | ||||
| 164 | mutex_unlock(&devpts_root->d_inode->i_mutex); | |||
| 165 | ||||
| 113 | 166 | return 0; | ||
| 167 | } | |||
| 168 | ||||
| 2557 | 0 | 169 | struct tty_struct *devpts_get_tty(int number) | |
| 170 | { | |||
| 171 | struct dentry *dentry = get_node(number); | |||
| 172 | struct tty_struct *tty; | |||
| 173 | ||||
| 174 | tty = NULL; | |||
| 2557 | 0 | - | 175 | if (!IS_ERR(dentry)) { |
| 2444 | 113 | 176 | if (dentry->d_inode) | |
| 177 | tty = dentry->d_inode->u.generic_ip; | |||
| 178 | dput(dentry); | |||
| 179 | } | |||
| 180 | ||||
| 181 | mutex_unlock(&devpts_root->d_inode->i_mutex); | |||
| 182 | ||||
| 2557 | 183 | return tty; | ||
| 184 | } | |||
| 185 | ||||
| 87 | 87 | 186 | void devpts_pty_kill(int number) | |
| 187 | { | |||
| 188 | struct dentry *dentry = get_node(number); | |||
| 189 | ||||
| 87 | 0 | - | 190 | if (!IS_ERR(dentry)) { |
| 191 | struct inode *inode = dentry->d_inode; | |||
| 87 | 0 | - | 192 | if (inode) { |
| 193 | inode->i_nlink--; | |||
| 194 | d_delete(dentry); | |||
| 195 | dput(dentry); | |||
| 196 | } | |||
| 197 | dput(dentry); | |||
| 198 | } | |||
| 199 | mutex_unlock(&devpts_root->d_inode->i_mutex); | |||
| 200 | } | |||
| 201 | ||||
| 6 | 0 | 202 | static int __init init_devpts_fs(void) | |
| 203 | { | |||
| 204 | int err = register_filesystem(&devpts_fs_type); | |||
| 6 | 0 | - | 205 | if (!err) { |
| 206 | devpts_mnt = kern_mount(&devpts_fs_type); | |||
| 0 | 6 | - | 207 | if (IS_ERR(devpts_mnt)) |
| 208 | err = PTR_ERR(devpts_mnt); | |||
| 209 | } | |||
| 6 | 210 | return err; | ||
| 211 | } | |||
| 212 | ||||
| 0 | 0 | - | 213 | static void __exit exit_devpts_fs(void) |
| 214 | { | |||
| 215 | unregister_filesystem(&devpts_fs_type); | |||
| 216 | mntput(devpts_mnt); | |||
| 217 | } | |||
| 218 | ||||
| 219 | module_init(init_devpts_fs) | |||
| 220 | module_exit(exit_devpts_fs) | |||
| 221 | MODULE_LICENSE("GPL"); | |||
| ***TER 61% (40/66) of SOURCE FILE inode.c | ||||