kernel/vserver/helper.c

   1 /*
   2  *  linux/kernel/vserver/helper.c
   3  *
   4  *  Virtual Context Support
   5  *
   6  *  Copyright (C) 2004-2005  Herbert Pötzl
   7  *
   8  *  V0.01  basic helper
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/errno.h>
  14 #include <linux/reboot.h>
  15 #include <linux/kmod.h>
  16 #include <linux/sched.h>
  17 #include <linux/vs_context.h>
  18 #include <linux/vs_network.h>
  19
  20 #include <asm/uaccess.h>
  21 #include <asm/unistd.h>
  22
  23
  24 char vshelper_path[255] = "/sbin/vshelper";
  25
  26
  27 int do_vshelper(char *name, char *argv[], char *envp[], int sync)
  28 {
  29         int ret;
  30
  31         if ((ret = call_usermodehelper(name, argv, envp, sync))) {
  32                 printk( KERN_WARNING
  33                         "%s: (%s %s) returned %s with %d\n",
  34                         name, argv[1], argv[2],
  35                         sync?"sync":"async", ret);
  36         }
  37         vxdprintk(VXD_CBIT(switch, 4),
  38                 "%s: (%s %s) returned %s with %d",
  39                 name, argv[1], argv[2], sync?"sync":"async", ret);
  40         return ret;
  41 }
  42
  43 /*
  44  *      vshelper path is set via /proc/sys
  45  *      invoked by vserver sys_reboot(), with
  46  *      the following arguments
  47  *
  48  *      argv [0] = vshelper_path;
  49  *      argv [1] = action: "restart", "halt", "poweroff", ...
  50  *      argv [2] = context identifier
  51  *
  52  *      envp [*] = type-specific parameters
  53  */
  54
  55 long vs_reboot(unsigned int cmd, void * arg)
  56 {
  57         char id_buf[8], cmd_buf[16];
  58         char uid_buf[16], pid_buf[16];
  59         int ret;
  60
  61         char *argv[] = {vshelper_path, NULL, id_buf, 0};
  62         char *envp[] = {"HOME=/", "TERM=linux",
  63                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
  64                         uid_buf, pid_buf, cmd_buf, 0};
  65
  66         snprintf(id_buf, sizeof(id_buf)-1, "%d", vx_current_xid());
  67
  68         snprintf(cmd_buf, sizeof(cmd_buf)-1, "VS_CMD=%08x", cmd);
  69         snprintf(uid_buf, sizeof(uid_buf)-1, "VS_UID=%d", current->uid);
  70         snprintf(pid_buf, sizeof(pid_buf)-1, "VS_PID=%d", current->pid);
  71
  72         switch (cmd) {
  73         case LINUX_REBOOT_CMD_RESTART:
  74                 argv[1] = "restart";
  75                 break;
  76
  77         case LINUX_REBOOT_CMD_HALT:
  78                 argv[1] = "halt";
  79                 break;
  80
  81         case LINUX_REBOOT_CMD_POWER_OFF:
  82                 argv[1] = "poweroff";
  83                 break;
  84
  85         case LINUX_REBOOT_CMD_SW_SUSPEND:
  86                 argv[1] = "swsusp";
  87                 break;
  88
  89         default:
  90                 return 0;
  91         }
  92
  93 #ifndef CONFIG_VSERVER_LEGACY
  94         ret = do_vshelper(vshelper_path, argv, envp, 1);
  95 #else
  96         ret = do_vshelper(vshelper_path, argv, envp, 0);
  97 #endif
  98         return (ret) ? -EPERM : 0;
  99 }
 100
 101
 102 /*
 103  *      argv [0] = vshelper_path;
 104  *      argv [1] = action: "startup", "shutdown"
 105  *      argv [2] = context identifier
 106  *
 107  *      envp [*] = type-specific parameters
 108  */
 109
 110 long vs_state_change(struct vx_info *vxi, unsigned int cmd)
 111 {
 112         char id_buf[8], cmd_buf[16];
 113         char *argv[] = {vshelper_path, NULL, id_buf, 0};
 114         char *envp[] = {"HOME=/", "TERM=linux",
 115                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin", cmd_buf, 0};
 116
 117         if (!vx_info_flags(vxi, VXF_STATE_HELPER, 0))
 118                 return 0;
 119
 120         snprintf(id_buf, sizeof(id_buf)-1, "%d", vxi->vx_id);
 121         snprintf(cmd_buf, sizeof(cmd_buf)-1, "VS_CMD=%08x", cmd);
 122
 123         switch (cmd) {
 124         case VSC_STARTUP:
 125                 argv[1] = "startup";
 126                 break;
 127         case VSC_SHUTDOWN:
 128                 argv[1] = "shutdown";
 129                 break;
 130         default:
 131                 return 0;
 132         }
 133
 134         do_vshelper(vshelper_path, argv, envp, 1);
 135         return 0;
 136 }
 137
 138
 139 /*
 140  *      argv [0] = vshelper_path;
 141  *      argv [1] = action: "netup", "netdown"
 142  *      argv [2] = context identifier
 143  *
 144  *      envp [*] = type-specific parameters
 145  */
 146
 147 long vs_net_change(struct nx_info *nxi, unsigned int cmd)
 148 {
 149         char id_buf[8], cmd_buf[16];
 150         char *argv[] = {vshelper_path, NULL, id_buf, 0};
 151         char *envp[] = {"HOME=/", "TERM=linux",
 152                         "PATH=/sbin:/usr/sbin:/bin:/usr/bin", cmd_buf, 0};
 153
 154         if (!nx_info_flags(nxi, NXF_STATE_HELPER, 0))
 155                 return 0;
 156
 157         snprintf(id_buf, sizeof(id_buf)-1, "%d", nxi->nx_id);
 158         snprintf(cmd_buf, sizeof(cmd_buf)-1, "VS_CMD=%08x", cmd);
 159
 160         switch (cmd) {
 161         case VSC_NETUP:
 162                 argv[1] = "netup";
 163                 break;
 164         case VSC_NETDOWN:
 165                 argv[1] = "netdown";
 166                 break;
 167         default:
 168                 return 0;
 169         }
 170
 171         do_vshelper(vshelper_path, argv, envp, 1);
 172         return 0;
 173 }
 174