include/linux/ipc_namespace.h

   1 #ifndef __IPC_NAMESPACE_H__
   2 #define __IPC_NAMESPACE_H__
   3
   4 #include <linux/err.h>
   5 #include <linux/idr.h>
   6 #include <linux/rwsem.h>
   7 #include <linux/notifier.h>
   8 #include <linux/nsproxy.h>
   9
  10 /*
  11  * ipc namespace events
  12  */
  13 #define IPCNS_MEMCHANGED   0x00000001   /* Notify lowmem size changed */
  14 #define IPCNS_CREATED  0x00000002   /* Notify new ipc namespace created */
  15 #define IPCNS_REMOVED  0x00000003   /* Notify ipc namespace removed */
  16
  17 #define IPCNS_CALLBACK_PRI 0
  18
  19 struct user_namespace;
  20
  21 struct ipc_ids {
  22         int in_use;
  23         unsigned short seq;
  24         unsigned short seq_max;
  25         struct rw_semaphore rw_mutex;
  26         struct idr ipcs_idr;
  27 };
  28
  29 struct ipc_namespace {
  30         atomic_t        count;
  31         struct ipc_ids  ids[3];
  32
  33         int             sem_ctls[4];
  34         int             used_sems;
  35
  36         int             msg_ctlmax;
  37         int             msg_ctlmnb;
  38         int             msg_ctlmni;
  39         atomic_t        msg_bytes;
  40         atomic_t        msg_hdrs;
  41         int             auto_msgmni;
  42
  43         size_t          shm_ctlmax;
  44         size_t          shm_ctlall;
  45         int             shm_ctlmni;
  46         int             shm_tot;
  47         /*
  48          * Defines whether IPC_RMID is forced for _all_ shm segments regardless
  49          * of shmctl()
  50          */
  51         int             shm_rmid_forced;
  52
  53         struct notifier_block ipcns_nb;
  54
  55         /* The kern_mount of the mqueuefs sb.  We take a ref on it */
  56         struct vfsmount *mq_mnt;
  57
  58         /* # queues in this ns, protected by mq_lock */
  59         unsigned int    mq_queues_count;
  60
  61         /* next fields are set through sysctl */
  62         unsigned int    mq_queues_max;   /* initialized to DFLT_QUEUESMAX */
  63         unsigned int    mq_msg_max;      /* initialized to DFLT_MSGMAX */
  64         unsigned int    mq_msgsize_max;  /* initialized to DFLT_MSGSIZEMAX */
  65         unsigned int    mq_msg_default;
  66         unsigned int    mq_msgsize_default;
  67
  68         /* user_ns which owns the ipc ns */
  69         struct user_namespace *user_ns;
  70
  71         unsigned int    proc_inum;
  72 };
  73
  74 extern struct ipc_namespace init_ipc_ns;
  75 extern atomic_t nr_ipc_ns;
  76
  77 extern spinlock_t mq_lock;
  78
  79 #ifdef CONFIG_SYSVIPC
  80 extern int register_ipcns_notifier(struct ipc_namespace *);
  81 extern int cond_register_ipcns_notifier(struct ipc_namespace *);
  82 extern void unregister_ipcns_notifier(struct ipc_namespace *);
  83 extern int ipcns_notify(unsigned long);
  84 extern void shm_destroy_orphaned(struct ipc_namespace *ns);
  85 #else /* CONFIG_SYSVIPC */
  86 static inline int register_ipcns_notifier(struct ipc_namespace *ns)
  87 { return 0; }
  88 static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
  89 { return 0; }
  90 static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
  91 static inline int ipcns_notify(unsigned long l) { return 0; }
  92 static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
  93 #endif /* CONFIG_SYSVIPC */
  94
  95 #ifdef CONFIG_POSIX_MQUEUE
  96 extern int mq_init_ns(struct ipc_namespace *ns);
  97 /*
  98  * POSIX Message Queue default values:
  99  *
 100  * MIN_*: Lowest value an admin can set the maximum unprivileged limit to
 101  * DFLT_*MAX: Default values for the maximum unprivileged limits
 102  * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
 103  *   an attribute to the open call and the queue must be created
 104  * HARD_*: Highest value the maximums can be set to.  These are enforced
 105  *   on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
 106  *   suitably high)
 107  *
 108  * POSIX Requirements:
 109  *   Per app minimum openable message queues - 8.  This does not map well
 110  *     to the fact that we limit the number of queues on a per namespace
 111  *     basis instead of a per app basis.  So, make the default high enough
 112  *     that no given app should have a hard time opening 8 queues.
 113  *   Minimum maximum for HARD_MSGMAX - 32767.  I bumped this to 65536.
 114  *   Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this.  However,
 115  *     we have run into a situation where running applications in the wild
 116  *     require this to be at least 5MB, and preferably 10MB, so I set the
 117  *     value to 16MB in hopes that this user is the worst of the bunch and
 118  *     the new maximum will handle anyone else.  I may have to revisit this
 119  *     in the future.
 120  */
 121 #define MIN_QUEUESMAX                   1
 122 #define DFLT_QUEUESMAX                256
 123 #define HARD_QUEUESMAX               1024
 124 #define MIN_MSGMAX                      1
 125 #define DFLT_MSG                       10U
 126 #define DFLT_MSGMAX                    10
 127 #define HARD_MSGMAX                 65536
 128 #define MIN_MSGSIZEMAX                128
 129 #define DFLT_MSGSIZE                 8192U
 130 #define DFLT_MSGSIZEMAX              8192
 131 #define HARD_MSGSIZEMAX     (16*1024*1024)
 132 #else
 133 static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
 134 #endif
 135
 136 #if defined(CONFIG_IPC_NS)
 137 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
 138         struct user_namespace *user_ns, struct ipc_namespace *ns);
 139
 140 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
 141 {
 142         if (ns)
 143                 atomic_inc(&ns->count);
 144         return ns;
 145 }
 146
 147 extern void put_ipc_ns(struct ipc_namespace *ns);
 148 #else
 149 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
 150         struct user_namespace *user_ns, struct ipc_namespace *ns)
 151 {
 152         if (flags & CLONE_NEWIPC)
 153                 return ERR_PTR(-EINVAL);
 154
 155         return ns;
 156 }
 157
 158 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
 159 {
 160         return ns;
 161 }
 162
 163 static inline void put_ipc_ns(struct ipc_namespace *ns)
 164 {
 165 }
 166 #endif
 167
 168 #ifdef CONFIG_POSIX_MQUEUE_SYSCTL
 169
 170 struct ctl_table_header;
 171 extern struct ctl_table_header *mq_register_sysctl_table(void);
 172
 173 #else /* CONFIG_POSIX_MQUEUE_SYSCTL */
 174
 175 static inline struct ctl_table_header *mq_register_sysctl_table(void)
 176 {
 177         return NULL;
 178 }
 179
 180 #endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
 181 #endif