xref: /linux/arch/x86/include/uapi/asm/sgx.h (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * Copyright(c) 2016-20 Intel Corporation.
4  */
5 #ifndef _UAPI_ASM_X86_SGX_H
6 #define _UAPI_ASM_X86_SGX_H
7 
8 #include <linux/types.h>
9 #include <linux/ioctl.h>
10 
11 /**
12  * enum sgx_page_flags - page control flags
13  * %SGX_PAGE_MEASURE:	Measure the page contents with a sequence of
14  *			ENCLS[EEXTEND] operations.
15  */
16 enum sgx_page_flags {
17 	SGX_PAGE_MEASURE	= 0x01,
18 };
19 
20 #define SGX_MAGIC 0xA4
21 
22 #define SGX_IOC_ENCLAVE_CREATE \
23 	_IOW(SGX_MAGIC, 0x00, struct sgx_enclave_create)
24 #define SGX_IOC_ENCLAVE_ADD_PAGES \
25 	_IOWR(SGX_MAGIC, 0x01, struct sgx_enclave_add_pages)
26 #define SGX_IOC_ENCLAVE_INIT \
27 	_IOW(SGX_MAGIC, 0x02, struct sgx_enclave_init)
28 #define SGX_IOC_ENCLAVE_PROVISION \
29 	_IOW(SGX_MAGIC, 0x03, struct sgx_enclave_provision)
30 #define SGX_IOC_VEPC_REMOVE_ALL \
31 	_IO(SGX_MAGIC, 0x04)
32 #define SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS \
33 	_IOWR(SGX_MAGIC, 0x05, struct sgx_enclave_restrict_permissions)
34 #define SGX_IOC_ENCLAVE_MODIFY_TYPES \
35 	_IOWR(SGX_MAGIC, 0x06, struct sgx_enclave_modify_types)
36 #define SGX_IOC_ENCLAVE_REMOVE_PAGES \
37 	_IOWR(SGX_MAGIC, 0x07, struct sgx_enclave_remove_pages)
38 
39 /**
40  * struct sgx_enclave_create - parameter structure for the
41  *                             %SGX_IOC_ENCLAVE_CREATE ioctl
42  * @src:	address for the SECS page data
43  */
44 struct sgx_enclave_create  {
45 	__u64	src;
46 };
47 
48 /**
49  * struct sgx_enclave_add_pages - parameter structure for the
50  *                                %SGX_IOC_ENCLAVE_ADD_PAGE ioctl
51  * @src:	start address for the page data
52  * @offset:	starting page offset
53  * @length:	length of the data (multiple of the page size)
54  * @secinfo:	address for the SECINFO data
55  * @flags:	page control flags
56  * @count:	number of bytes added (multiple of the page size)
57  */
58 struct sgx_enclave_add_pages {
59 	__u64 src;
60 	__u64 offset;
61 	__u64 length;
62 	__u64 secinfo;
63 	__u64 flags;
64 	__u64 count;
65 };
66 
67 /**
68  * struct sgx_enclave_init - parameter structure for the
69  *                           %SGX_IOC_ENCLAVE_INIT ioctl
70  * @sigstruct:	address for the SIGSTRUCT data
71  */
72 struct sgx_enclave_init {
73 	__u64 sigstruct;
74 };
75 
76 /**
77  * struct sgx_enclave_provision - parameter structure for the
78  *				  %SGX_IOC_ENCLAVE_PROVISION ioctl
79  * @fd:		file handle of /dev/sgx_provision
80  */
81 struct sgx_enclave_provision {
82 	__u64 fd;
83 };
84 
85 /**
86  * struct sgx_enclave_restrict_permissions - parameters for ioctl
87  *                                        %SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS
88  * @offset:	starting page offset (page aligned relative to enclave base
89  *		address defined in SECS)
90  * @length:	length of memory (multiple of the page size)
91  * @permissions:new permission bits for pages in range described by @offset
92  *              and @length
93  * @result:	(output) SGX result code of ENCLS[EMODPR] function
94  * @count:	(output) bytes successfully changed (multiple of page size)
95  */
96 struct sgx_enclave_restrict_permissions {
97 	__u64 offset;
98 	__u64 length;
99 	__u64 permissions;
100 	__u64 result;
101 	__u64 count;
102 };
103 
104 /**
105  * struct sgx_enclave_modify_types - parameters for ioctl
106  *                                   %SGX_IOC_ENCLAVE_MODIFY_TYPES
107  * @offset:	starting page offset (page aligned relative to enclave base
108  *		address defined in SECS)
109  * @length:	length of memory (multiple of the page size)
110  * @page_type:	new type for pages in range described by @offset and @length
111  * @result:	(output) SGX result code of ENCLS[EMODT] function
112  * @count:	(output) bytes successfully changed (multiple of page size)
113  */
114 struct sgx_enclave_modify_types {
115 	__u64 offset;
116 	__u64 length;
117 	__u64 page_type;
118 	__u64 result;
119 	__u64 count;
120 };
121 
122 /**
123  * struct sgx_enclave_remove_pages - %SGX_IOC_ENCLAVE_REMOVE_PAGES parameters
124  * @offset:	starting page offset (page aligned relative to enclave base
125  *		address defined in SECS)
126  * @length:	length of memory (multiple of the page size)
127  * @count:	(output) bytes successfully changed (multiple of page size)
128  *
129  * Regular (PT_REG) or TCS (PT_TCS) can be removed from an initialized
130  * enclave if the system supports SGX2. First, the %SGX_IOC_ENCLAVE_MODIFY_TYPES
131  * ioctl() should be used to change the page type to PT_TRIM. After that
132  * succeeds ENCLU[EACCEPT] should be run from within the enclave and then
133  * %SGX_IOC_ENCLAVE_REMOVE_PAGES can be used to complete the page removal.
134  */
135 struct sgx_enclave_remove_pages {
136 	__u64 offset;
137 	__u64 length;
138 	__u64 count;
139 };
140 
141 struct sgx_enclave_run;
142 
143 /**
144  * typedef sgx_enclave_user_handler_t - Exit handler function accepted by
145  *					__vdso_sgx_enter_enclave()
146  * @run:	The run instance given by the caller
147  *
148  * The register parameters contain the snapshot of their values at enclave
149  * exit. An invalid ENCLU function number will cause -EINVAL to be returned
150  * to the caller.
151  *
152  * Return:
153  * - <= 0:	The given value is returned back to the caller.
154  * - > 0:	ENCLU function to invoke, either EENTER or ERESUME.
155  */
156 typedef int (*sgx_enclave_user_handler_t)(long rdi, long rsi, long rdx,
157 					  long rsp, long r8, long r9,
158 					  struct sgx_enclave_run *run);
159 
160 /**
161  * struct sgx_enclave_run - the execution context of __vdso_sgx_enter_enclave()
162  * @tcs:			TCS used to enter the enclave
163  * @function:			The last seen ENCLU function (EENTER, ERESUME or EEXIT)
164  * @exception_vector:		The interrupt vector of the exception
165  * @exception_error_code:	The exception error code pulled out of the stack
166  * @exception_addr:		The address that triggered the exception
167  * @user_handler:		User provided callback run on exception
168  * @user_data:			Data passed to the user handler
169  * @reserved			Reserved for future extensions
170  *
171  * If @user_handler is provided, the handler will be invoked on all return paths
172  * of the normal flow.  The user handler may transfer control, e.g. via a
173  * longjmp() call or a C++ exception, without returning to
174  * __vdso_sgx_enter_enclave().
175  */
176 struct sgx_enclave_run {
177 	__u64 tcs;
178 	__u32 function;
179 	__u16 exception_vector;
180 	__u16 exception_error_code;
181 	__u64 exception_addr;
182 	__u64 user_handler;
183 	__u64 user_data;
184 	__u8  reserved[216];
185 };
186 
187 /**
188  * typedef vdso_sgx_enter_enclave_t - Prototype for __vdso_sgx_enter_enclave(),
189  *				      a vDSO function to enter an SGX enclave.
190  * @rdi:	Pass-through value for RDI
191  * @rsi:	Pass-through value for RSI
192  * @rdx:	Pass-through value for RDX
193  * @function:	ENCLU function, must be EENTER or ERESUME
194  * @r8:		Pass-through value for R8
195  * @r9:		Pass-through value for R9
196  * @run:	struct sgx_enclave_run, must be non-NULL
197  *
198  * NOTE: __vdso_sgx_enter_enclave() does not ensure full compliance with the
199  * x86-64 ABI, e.g. doesn't handle XSAVE state.  Except for non-volatile
200  * general purpose registers, EFLAGS.DF, and RSP alignment, preserving/setting
201  * state in accordance with the x86-64 ABI is the responsibility of the enclave
202  * and its runtime, i.e. __vdso_sgx_enter_enclave() cannot be called from C
203  * code without careful consideration by both the enclave and its runtime.
204  *
205  * All general purpose registers except RAX, RBX and RCX are passed as-is to the
206  * enclave.  RAX, RBX and RCX are consumed by EENTER and ERESUME and are loaded
207  * with @function, asynchronous exit pointer, and @run.tcs respectively.
208  *
209  * RBP and the stack are used to anchor __vdso_sgx_enter_enclave() to the
210  * pre-enclave state, e.g. to retrieve @run.exception and @run.user_handler
211  * after an enclave exit.  All other registers are available for use by the
212  * enclave and its runtime, e.g. an enclave can push additional data onto the
213  * stack (and modify RSP) to pass information to the optional user handler (see
214  * below).
215  *
216  * Most exceptions reported on ENCLU, including those that occur within the
217  * enclave, are fixed up and reported synchronously instead of being delivered
218  * via a standard signal. Debug Exceptions (#DB) and Breakpoints (#BP) are
219  * never fixed up and are always delivered via standard signals. On synchronously
220  * reported exceptions, -EFAULT is returned and details about the exception are
221  * recorded in @run.exception, the optional sgx_enclave_exception struct.
222  *
223  * Return:
224  * - 0:		ENCLU function was successfully executed.
225  * - -EINVAL:	Invalid ENCL number (neither EENTER nor ERESUME).
226  */
227 typedef int (*vdso_sgx_enter_enclave_t)(unsigned long rdi, unsigned long rsi,
228 					unsigned long rdx, unsigned int function,
229 					unsigned long r8,  unsigned long r9,
230 					struct sgx_enclave_run *run);
231 
232 #endif /* _UAPI_ASM_X86_SGX_H */
233