xnu-3789.21.4.tar.gz

[apple/xnu.git] / bsd / sys / cprotect.h

diff --git a/bsd/sys/cprotect.h b/bsd/sys/cprotect.h
index 9a7c36d773df126032bea5cc9ac5b71cbe8bbccc..97cb5a7c11339f7bb7a5e7e1d5fe43e38b79f23d 100644 (file)
--- a/bsd/sys/cprotect.h
+++ b/bsd/sys/cprotect.h
@@ -1,5 +1,5 @@
 /*
 /*

- * Copyright (c) 2009-2012 Apple Inc. All rights reserved.
+ * Copyright (c) 2009-2014 Apple Inc. All rights reserved.

  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *


@@ -29,238 +29,179 @@
 #ifndef _SYS_CPROTECT_H_
 #define        _SYS_CPROTECT_H_
 
 #ifndef _SYS_CPROTECT_H_
 #define        _SYS_CPROTECT_H_
 

-#ifdef __cplusplus
-extern "C" {
-#endif
-

 #if KERNEL_PRIVATE
 
 #include <sys/cdefs.h>
 #if KERNEL_PRIVATE
 
 #include <sys/cdefs.h>

-#include <sys/content_protection.h>
-#include <sys/kernel_types.h>
+#include <sys/param.h>
+#include <sys/buf.h>
+#include <sys/kdebug.h>

 #include <crypto/aes.h>
 #include <crypto/aes.h>

+#include <stdbool.h>

 
 

-#define CP_IV_KEYSIZE             20   /* 16x8 = 128, but SHA1 pushes 20 bytes so keep space for that */
-#define CP_MAX_KEYSIZE            32   /* 8x4 = 32, 32x8 = 256 */
-#define CP_MAX_WRAPPEDKEYSIZE     128  /* The size of the largest allowed key */
-#define CP_INITIAL_WRAPPEDKEYSIZE 40
-#define CP_V2_WRAPPEDKEYSIZE      40   /* Size of the wrapped key in a v2 EA */
-#define CP_V4_RESERVEDBYTES       20   /* Number of reserved bytes in EA still present */
+__BEGIN_DECLS

 
 

-/* lock events from AppleKeyStore */
-#define CP_LOCKED_STATE           0    /* Device is locked */
-#define CP_UNLOCKED_STATE         1    /* Device is unlocked */
+#define CP_CODE(code) FSDBG_CODE(DBG_CONTENT_PROT, code)
+/* 
+ * Class DBG_FSYSTEM == 0x03
+ * Subclass DBG_CONTENT_PROT == 0xCF
+ * These debug codes are of the form 0x03CFzzzz
+ */

 
 

-#define CP_MAX_STATE                     1     /* uint8_t ; maximum # of states is 255 */
+enum {
+       CPDBG_OFFSET_IO = CP_CODE(0),   /* 0x03CF0000 */
+};

 
 

-#define CP_LOCKED_KEYCHAIN        0
-#define CP_UNLOCKED_KEYCHAIN      1
+/* normally the debug events are no-ops */
+#define CP_DEBUG(x,a,b,c,d,e) do {} while (0);

 
 

-/* For struct cprotect: cp_flags */
-#define CP_NEEDS_KEYS             0x01 /* File needs persistent keys */
-#define CP_KEY_FLUSHED            0x02 /* File's unwrapped key has been purged from memory */
-#define CP_NO_XATTR               0x04 /* Key info has not been saved as EA to the FS */
-#define CP_OFF_IV_ENABLED         0x08 /* Only go down relative IV route if this flag is set */
-#define CP_RELOCATION_INFLIGHT    0x10 /* File with offset IVs is in the process of being relocated. */
-#define CP_SEP_WRAPPEDKEY                0x20  /* Wrapped key delivered from keybag */
+/* dev kernels only! */
+#if !SECURE_KERNEL 

 
 

-/* Content Protection VNOP Operation flags */
-#define CP_READ_ACCESS            0x1
-#define CP_WRITE_ACCESS           0x2
+/* KDEBUG events used by content protection subsystem */
+#if 0
+#undef CP_DEBUG
+#define CP_DEBUG KERNEL_DEBUG_CONSTANT
+#endif

 
 

+#endif
+
+#define CP_MAX_WRAPPEDKEYSIZE     128  /* The size of the largest allowed key */
+
+/* lock events from AppleKeyStore */
+enum {
+       CP_ACTION_LOCKED        = 0,
+       CP_ACTION_UNLOCKED      = 1,
+};

 /*
 /*

- * Check for this version when deciding to enable features
- * For iOS 4, CP_CURRENT_MAJOR_VERS = 2.0
- * For iOS 5, CP_CURRENT_MAJOR_VERS = 4.0
+ * Ideally, cp_key_store_action_t would be an enum, but we cannot fix
+ * that until AppleKeyStore is updated.

  */
  */

-#define CONTENT_PROTECTION_XATTR_NAME  "com.apple.system.cprotect"
-#define CP_NEW_MAJOR_VERS         4
-#define CP_PREV_MAJOR_VERS        2
-#define CP_MINOR_VERS             0
+typedef int cp_key_store_action_t;
+
+/*
+ * It was once the case (and it may still be the case) where the lock
+ * state got conflated with the possible actions/events that
+ * AppleKeyStore can send.  For that reason, the locked states below
+ * should numerically match their corresponding actions above.
+ */
+typedef unsigned char cp_lock_state_t;
+enum {
+       CP_LOCKED_STATE         = 0,
+       CP_UNLOCKED_STATE       = 1,
+};
+
+typedef uint32_t cp_key_class_t;
+typedef uint32_t cp_key_os_version_t;
+typedef uint16_t cp_key_revision_t;
+typedef uint64_t cp_crypto_id_t;

 
 typedef struct cprotect *cprotect_t;
 typedef struct cp_wrap_func *cp_wrap_func_t;
 
 typedef struct cprotect *cprotect_t;
 typedef struct cp_wrap_func *cp_wrap_func_t;

-typedef struct cp_global_state *cp_global_state_t;
-typedef struct cp_xattr *cp_xattr_t;
+typedef struct cpx *cpx_t;

 
 

-typedef struct cnode * cnode_ptr_t;
-//forward declare the struct.
-struct hfsmount;
+typedef struct cp_key {
+       uint8_t len;
+       void *key;
+} cp_key_t;

 
 

-/* Structures passed between HFS and AKS kext */
+/* Interface to AKS kext */

 typedef struct {
        void     *key;
        unsigned key_len;
        void     *iv_key;
        unsigned iv_key_len;
        uint32_t flags;
 typedef struct {
        void     *key;
        unsigned key_len;
        void     *iv_key;
        unsigned iv_key_len;
        uint32_t flags;

-} cp_raw_key_s, *cp_raw_key_t;
+} cp_raw_key_s;
+
+typedef cp_raw_key_s* cp_raw_key_t;

 
 typedef struct {
        void     *key;
        unsigned key_len;
 
 typedef struct {
        void     *key;
        unsigned key_len;

-       uint32_t dp_class;
-} cp_wrapped_key_s, *cp_wrapped_key_t;
+       cp_key_class_t dp_class;
+} cp_wrapped_key_s;
+
+typedef cp_wrapped_key_s* cp_wrapped_key_t;

 
 typedef struct {
 
 typedef struct {

-       ino64_t  inode;
-       uint32_t volume;
-       pid_t    pid;
-       uid_t    uid;
-} cp_cred_s, *cp_cred_t;
+       union {
+               ino64_t                 inode;
+               cp_crypto_id_t  crypto_id;
+       };
+       uint32_t                        volume;
+       pid_t                           pid;
+       uid_t                           uid;
+       cp_key_revision_t       key_revision;
+} cp_cred_s;
+
+typedef cp_cred_s* cp_cred_t;

 
 /* The wrappers are invoked on the AKS kext */
 typedef int unwrapper_t(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in, cp_raw_key_t key_out);
 
 /* The wrappers are invoked on the AKS kext */
 typedef int unwrapper_t(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in, cp_raw_key_t key_out);

-typedef int rewrapper_t(cp_cred_t access, uint32_t dp_class, const cp_wrapped_key_t wrapped_key_in, cp_wrapped_key_t wrapped_key_out);
-typedef int new_key_t(cp_cred_t access, uint32_t dp_class, cp_raw_key_t key_out, cp_wrapped_key_t wrapped_key_out);
+typedef int rewrapper_t(cp_cred_t access, cp_key_class_t dp_class, const cp_wrapped_key_t wrapped_key_in, cp_wrapped_key_t wrapped_key_out);
+typedef int new_key_t(cp_cred_t access, cp_key_class_t dp_class, cp_raw_key_t key_out, cp_wrapped_key_t wrapped_key_out);

 typedef int invalidater_t(cp_cred_t access); /* invalidates keys */
 typedef int invalidater_t(cp_cred_t access); /* invalidates keys */

+typedef int backup_key_t(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in, cp_wrapped_key_t wrapped_key_out);

 
 

-
-/* Flags for Interaction between AKS / Kernel */
-#define CP_RAW_KEY_WRAPPEDKEY 0x00000001
-
+/* 
+ * Flags for Interaction between AKS / Kernel 
+ * These are twiddled via the input/output structs in the above
+ * wrapper/unwrapper functions.
+ */
+#define CP_RAW_KEY_WRAPPEDKEY  0x00000001

 
 /*
 
 /*

- * Runtime-only structure containing the content protection status
- * for the given file.  This is contained within the cnode
- * This is passed down to IOStorageFamily via the bufattr struct
- *
- ******************************************************
- * Some Key calculation information for offset based IV
- ******************************************************
- * Kf  = original 256 bit per file key
- * Kiv = SHA1(Kf), use full Kf, but truncate Kiv to 128 bits
- * Kiv can be cached in the cprotect, so it only has to be calculated once for the file init
- *
- * IVb = Encrypt(Kiv, offset)
- *
+ * Function prototypes for kexts to interface with our internal cprotect
+ * fields;  cpx provides opacity and allows us to modify behavior internally
+ * without requiring kext changes.

  */
  */

-struct cprotect {
-       uint32_t        cp_flags;
-       uint32_t        cp_pclass;
-       aes_encrypt_ctx cp_cache_iv_ctx;
-       uint32_t        cp_cache_key_len;
-       uint8_t         cp_cache_key[CP_MAX_KEYSIZE];
-       uint32_t        cp_persistent_key_len;
-       void*           cp_backing_cnode;
-       uint8_t         cp_persistent_key[];
-};
-
+cpx_t cpx_alloc(size_t key_size);
+void cpx_init(cpx_t, size_t key_len);
+void cpx_free(cpx_t);
+__attribute__((const)) size_t cpx_size(size_t key_size);
+__attribute__((pure)) bool cpx_is_sep_wrapped_key(const struct cpx *);
+void cpx_set_is_sep_wrapped_key(struct cpx *, bool);
+__attribute__((pure)) bool cpx_use_offset_for_iv(const struct cpx *);
+void cpx_set_use_offset_for_iv(struct cpx *, bool);
+__attribute__((pure)) bool cpx_synthetic_offset_for_iv(const struct cpx *);
+void cpx_set_synthetic_offset_for_iv(struct cpx *, bool);
+__attribute__((pure)) uint16_t cpx_key_len(const struct cpx *);
+void cpx_set_key_len(struct cpx *, uint16_t key_len);
+__attribute__((pure)) void *cpx_key(const struct cpx *);
+aes_encrypt_ctx *cpx_iv_aes_ctx(struct cpx *);
+void cpx_flush(cpx_t cpx);
+bool cpx_can_copy(const struct cpx *src, const struct cpx *dst);
+void cpx_copy(const struct cpx *src, cpx_t dst);
+uint16_t cpx_max_key_len(const struct cpx *cpx);
+bool cpx_has_key(const struct cpx *cpx);
+size_t cpx_sizex(const struct cpx *cpx);
+void cpx_set_aes_iv_key(struct cpx *cpx, void *iv_key);
+
+/* Structure to store pointers for AKS functions */

 struct cp_wrap_func {
        new_key_t       *new_key;
        unwrapper_t     *unwrapper;
        rewrapper_t     *rewrapper;
        invalidater_t   *invalidater;
 struct cp_wrap_func {
        new_key_t       *new_key;
        unwrapper_t     *unwrapper;
        rewrapper_t     *rewrapper;
        invalidater_t   *invalidater;

+       backup_key_t    *backup_key;

 };
 
 };
 

-struct cp_global_state {
-       uint8_t wrap_functions_set;
-       uint8_t lock_state;
-       u_int16_t reserved;
-};
-
-/*
- * On-disk structure written as the per-file EA payload
- * All on-disk multi-byte fields for the CP XATTR must be stored
- * little-endian on-disk.  This means they must be endian swapped to
- * L.E on getxattr() and converted to LE on setxattr().
- *
- * This structure is a fixed length and is tightly packed.
- * 56 bytes total.
- */
-struct cp_xattr_v2 {
-       u_int16_t xattr_major_version;
-       u_int16_t xattr_minor_version;
-       u_int32_t flags;
-       u_int32_t persistent_class;
-       u_int32_t key_size;
-       uint8_t   persistent_key[CP_V2_WRAPPEDKEYSIZE];
-} __attribute__((aligned(2), packed));
-
-
-/*
- * V4 Content Protection EA On-Disk Layout.
- *
- * This structure must be tightly packed, but the *size can vary*
- * depending on the length of the key.  At MOST, the key length will be
- * CP_MAX_WRAPPEDKEYSIZE, but the length is defined by the key_size field.
- *
- * Either way, the packing must be applied to ensure that the key data is
- * retrievable in the right location relative to the start of the struct.
- *
- * Fully packed, this structure can range from :
- *             MIN: 36 bytes (no key -- used with directories)
- *             MAX: 164 bytes (with 128 byte key)
- *
- * During runtime we always allocate with the full 128 byte key, but only
- * use as much of the key buffer as needed. It must be tightly packed, though.
- */
-
-struct cp_xattr_v4 {
-       u_int16_t xattr_major_version;
-       u_int16_t xattr_minor_version;
-       u_int32_t flags;
-       u_int32_t persistent_class;
-       u_int32_t key_size;
-       /* CP V4 Reserved Bytes == 20 */
-       u_int8_t reserved[CP_V4_RESERVEDBYTES];
-       /* All above fields are fixed regardless of key length (36 bytes) */
-       /* Max Wrapped Size == 128 */
-       uint8_t   persistent_key[CP_MAX_WRAPPEDKEYSIZE];
-} __attribute__((aligned(2), packed));
-
-
-/*
- * The Root Directory's EA (fileid 1) is special; it defines information about
- * what capabilities the filesystem is using.
- *
- * The data is still stored little endian.
- *
- * Note that this structure is tightly packed: 28 bytes total.
- */
- struct cp_root_xattr {
-       u_int16_t major_version;
-       u_int16_t minor_version;
-       u_int64_t flags;
-       u_int8_t reserved[16];
-} __attribute__((aligned(2), packed));
-
-
-/*
- * Functions to check the status of a CP and to query
- * the containing filesystem to see if it is supported.
- */
-int cp_vnode_getclass(vnode_t, int *);
-int cp_vnode_setclass(vnode_t, uint32_t);
-int cp_vnode_transcode(vnode_t);
-
-int cp_key_store_action(int);
+int cp_key_store_action(cp_key_store_action_t);

 int cp_register_wraps(cp_wrap_func_t);
 int cp_register_wraps(cp_wrap_func_t);

-
-int cp_entry_init(cnode_ptr_t, struct mount *);
-int cp_entry_gentempkeys(struct cprotect **entry_ptr, struct hfsmount *hfsmp);
-int cp_needs_tempkeys (struct hfsmount *hfsmp, int* needs);
-void cp_entry_destroy(struct cprotect *entry_ptr);
-void cp_replace_entry (struct cnode *cp, struct cprotect *newentry);
-cnode_ptr_t cp_get_protected_cnode(vnode_t);
-int cp_handle_vnop(vnode_t, int, int);
-int cp_fs_protected (mount_t);
-int cp_getrootxattr (struct hfsmount *hfsmp, struct cp_root_xattr *outxattr);
-int cp_setrootxattr (struct hfsmount *hfsmp, struct cp_root_xattr *newxattr);
-int cp_setxattr(struct cnode *cp, struct cprotect *entry, struct hfsmount *hfsmp, uint32_t fileid, int options);
-int cp_generate_keys (struct hfsmount *hfsmp, struct cnode *cp, int targetclass, struct cprotect **newentry);
-int cp_setup_newentry (struct hfsmount *hfsmp, struct cnode *dcp, int32_t suppliedclass, 
-               mode_t cmode, struct cprotect **tmpentry);
-int cp_handle_relocate (cnode_ptr_t cp, struct hfsmount *hfsmp);
-int cp_handle_open(struct vnode *vp, int mode);
-int cp_get_root_major_vers (struct vnode *vp, uint32_t *level);
-int cp_get_default_level (struct vnode *vp, uint32_t *level);
+int cp_rewrap_key(cp_cred_t access, cp_key_class_t dp_class,
+                                 const cp_wrapped_key_t wrapped_key_in,
+                                 cp_wrapped_key_t wrapped_key_out);
+int cp_new_key(cp_cred_t access, cp_key_class_t dp_class, cp_raw_key_t key_out,
+                          cp_wrapped_key_t wrapped_key_out);
+int cp_unwrap_key(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in,
+                                 cp_raw_key_t key_out);
+int cp_get_backup_key(cp_cred_t access, const cp_wrapped_key_t wrapped_key_in,
+                                         cp_wrapped_key_t wrapped_key_out);
+cp_key_os_version_t cp_os_version(void);
+// Should be cp_key_class_t but HFS has a conflicting definition

 int cp_is_valid_class (int isdir, int32_t protectionclass);
 
 int cp_is_valid_class (int isdir, int32_t protectionclass);
 

-#endif /* KERNEL_PRIVATE */
-
-#ifdef __cplusplus
-};
-#endif
+__END_DECLS

 
 

+#endif /* KERNEL_PRIVATE */

 #endif /* !_SYS_CPROTECT_H_ */
 #endif /* !_SYS_CPROTECT_H_ */