kernel/generic/include/cap/cap.h

   1 /*
   2  * Copyright (c) 2017 Jakub Jermar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup kernel_generic
  30  * @{
  31  */
  32 /** @file
  33  */
  34
  35 #ifndef KERN_CAP_H_
  36 #define KERN_CAP_H_
  37
  38 #include <abi/cap.h>
  39 #include <typedefs.h>
  40 #include <adt/list.h>
  41 #include <adt/hash.h>
  42 #include <adt/hash_table.h>
  43 #include <lib/ra.h>
  44 #include <synch/mutex.h>
  45 #include <atomic.h>
  46
  47 typedef enum {
  48         CAP_STATE_FREE,
  49         CAP_STATE_ALLOCATED,
  50         CAP_STATE_PUBLISHED
  51 } cap_state_t;
  52
  53 typedef enum {
  54         KOBJECT_TYPE_CALL,
  55         KOBJECT_TYPE_IRQ,
  56         KOBJECT_TYPE_PHONE,
  57         KOBJECT_TYPE_WAITQ,
  58         KOBJECT_TYPE_MAX
  59 } kobject_type_t;
  60
  61 struct task;
  62
  63 struct call;
  64 struct irq;
  65 struct phone;
  66 struct waitq;
  67
  68 typedef struct kobject_ops {
  69         void (*destroy)(void *);
  70 } kobject_ops_t;
  71
  72 /*
  73  * Everything in kobject_t except for the atomic reference count, the capability
  74  * list and its lock is imutable.
  75  */
  76 typedef struct kobject {
  77         kobject_type_t type;
  78         atomic_t refcnt;
  79
  80         /** Mutex protecting caps_list */
  81         mutex_t caps_list_lock;
  82         /** List of published capabilities associated with the kobject */
  83         list_t caps_list;
  84
  85         kobject_ops_t *ops;
  86
  87         union {
  88                 void *raw;
  89                 struct call *call;
  90                 struct irq *irq;
  91                 struct phone *phone;
  92                 struct waitq *waitq;
  93         };
  94 } kobject_t;
  95
  96 /*
  97  * A cap_t may only be accessed under the protection of the cap_info_t lock.
  98  */
  99 typedef struct cap {
 100         cap_state_t state;
 101
 102         struct task *task;
 103         cap_handle_t handle;
 104
 105         /** Link to the kobject's list of capabilities. */
 106         link_t kobj_link;
 107
 108         /* Link to the task's capabilities of the same kobject type. */
 109         link_t type_link;
 110
 111         ht_link_t caps_link;
 112
 113         /* The underlying kernel object. */
 114         kobject_t *kobject;
 115 } cap_t;
 116
 117 typedef struct cap_info {
 118         mutex_t lock;
 119
 120         list_t type_list[KOBJECT_TYPE_MAX];
 121
 122         hash_table_t caps;
 123         ra_arena_t *handles;
 124 } cap_info_t;
 125
 126 extern void caps_init(void);
 127 extern errno_t caps_task_alloc(struct task *);
 128 extern void caps_task_free(struct task *);
 129 extern void caps_task_init(struct task *);
 130 extern bool caps_apply_to_kobject_type(struct task *, kobject_type_t,
 131     bool (*)(cap_t *, void *), void *);
 132
 133 extern errno_t cap_alloc(struct task *, cap_handle_t *);
 134 extern void cap_publish(struct task *, cap_handle_t, kobject_t *);
 135 extern kobject_t *cap_unpublish(struct task *, cap_handle_t, kobject_type_t);
 136 extern void cap_revoke(kobject_t *);
 137 extern void cap_free(struct task *, cap_handle_t);
 138
 139 extern kobject_t *kobject_alloc(unsigned int);
 140 extern void kobject_free(kobject_t *);
 141 extern void kobject_initialize(kobject_t *, kobject_type_t, void *,
 142     kobject_ops_t *);
 143 extern kobject_t *kobject_get(struct task *, cap_handle_t, kobject_type_t);
 144 extern void kobject_add_ref(kobject_t *);
 145 extern void kobject_put(kobject_t *);
 146
 147 #endif
 148
 149 /** @}
 150  */