xref: /openbmc/linux/arch/x86/include/asm/sgx.h (revision 63705da3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /**
3  * Copyright(c) 2016-20 Intel Corporation.
4  *
5  * Intel Software Guard Extensions (SGX) support.
6  */
7 #ifndef _ASM_X86_SGX_H
8 #define _ASM_X86_SGX_H
9 
10 #include <linux/bits.h>
11 #include <linux/types.h>
12 
13 /*
14  * This file contains both data structures defined by SGX architecture and Linux
15  * defined software data structures and functions.  The two should not be mixed
16  * together for better readability.  The architectural definitions come first.
17  */
18 
19 /* The SGX specific CPUID function. */
20 #define SGX_CPUID		0x12
21 /* EPC enumeration. */
22 #define SGX_CPUID_EPC		2
23 /* An invalid EPC section, i.e. the end marker. */
24 #define SGX_CPUID_EPC_INVALID	0x0
25 /* A valid EPC section. */
26 #define SGX_CPUID_EPC_SECTION	0x1
27 /* The bitmask for the EPC section type. */
28 #define SGX_CPUID_EPC_MASK	GENMASK(3, 0)
29 
30 enum sgx_encls_function {
31 	ECREATE	= 0x00,
32 	EADD	= 0x01,
33 	EINIT	= 0x02,
34 	EREMOVE	= 0x03,
35 	EDGBRD	= 0x04,
36 	EDGBWR	= 0x05,
37 	EEXTEND	= 0x06,
38 	ELDU	= 0x08,
39 	EBLOCK	= 0x09,
40 	EPA	= 0x0A,
41 	EWB	= 0x0B,
42 	ETRACK	= 0x0C,
43 	EAUG	= 0x0D,
44 	EMODPR	= 0x0E,
45 	EMODT	= 0x0F,
46 };
47 
48 /**
49  * enum sgx_return_code - The return code type for ENCLS, ENCLU and ENCLV
50  * %SGX_NOT_TRACKED:		Previous ETRACK's shootdown sequence has not
51  *				been completed yet.
52  * %SGX_CHILD_PRESENT		SECS has child pages present in the EPC.
53  * %SGX_INVALID_EINITTOKEN:	EINITTOKEN is invalid and enclave signer's
54  *				public key does not match IA32_SGXLEPUBKEYHASH.
55  * %SGX_UNMASKED_EVENT:		An unmasked event, e.g. INTR, was received
56  */
57 enum sgx_return_code {
58 	SGX_NOT_TRACKED			= 11,
59 	SGX_CHILD_PRESENT		= 13,
60 	SGX_INVALID_EINITTOKEN		= 16,
61 	SGX_UNMASKED_EVENT		= 128,
62 };
63 
64 /* The modulus size for 3072-bit RSA keys. */
65 #define SGX_MODULUS_SIZE 384
66 
67 /**
68  * enum sgx_miscselect - additional information to an SSA frame
69  * %SGX_MISC_EXINFO:	Report #PF or #GP to the SSA frame.
70  *
71  * Save State Area (SSA) is a stack inside the enclave used to store processor
72  * state when an exception or interrupt occurs. This enum defines additional
73  * information stored to an SSA frame.
74  */
75 enum sgx_miscselect {
76 	SGX_MISC_EXINFO		= BIT(0),
77 };
78 
79 #define SGX_MISC_RESERVED_MASK	GENMASK_ULL(63, 1)
80 
81 #define SGX_SSA_GPRS_SIZE		184
82 #define SGX_SSA_MISC_EXINFO_SIZE	16
83 
84 /**
85  * enum sgx_attributes - the attributes field in &struct sgx_secs
86  * %SGX_ATTR_INIT:		Enclave can be entered (is initialized).
87  * %SGX_ATTR_DEBUG:		Allow ENCLS(EDBGRD) and ENCLS(EDBGWR).
88  * %SGX_ATTR_MODE64BIT:		Tell that this a 64-bit enclave.
89  * %SGX_ATTR_PROVISIONKEY:      Allow to use provisioning keys for remote
90  *				attestation.
91  * %SGX_ATTR_KSS:		Allow to use key separation and sharing (KSS).
92  * %SGX_ATTR_EINITTOKENKEY:	Allow to use token signing key that is used to
93  *				sign cryptographic tokens that can be passed to
94  *				EINIT as an authorization to run an enclave.
95  */
96 enum sgx_attribute {
97 	SGX_ATTR_INIT		= BIT(0),
98 	SGX_ATTR_DEBUG		= BIT(1),
99 	SGX_ATTR_MODE64BIT	= BIT(2),
100 	SGX_ATTR_PROVISIONKEY	= BIT(4),
101 	SGX_ATTR_EINITTOKENKEY	= BIT(5),
102 	SGX_ATTR_KSS		= BIT(7),
103 };
104 
105 #define SGX_ATTR_RESERVED_MASK	(BIT_ULL(3) | BIT_ULL(6) | GENMASK_ULL(63, 8))
106 
107 /**
108  * struct sgx_secs - SGX Enclave Control Structure (SECS)
109  * @size:		size of the address space
110  * @base:		base address of the  address space
111  * @ssa_frame_size:	size of an SSA frame
112  * @miscselect:		additional information stored to an SSA frame
113  * @attributes:		attributes for enclave
114  * @xfrm:		XSave-Feature Request Mask (subset of XCR0)
115  * @mrenclave:		SHA256-hash of the enclave contents
116  * @mrsigner:		SHA256-hash of the public key used to sign the SIGSTRUCT
117  * @config_id:		a user-defined value that is used in key derivation
118  * @isv_prod_id:	a user-defined value that is used in key derivation
119  * @isv_svn:		a user-defined value that is used in key derivation
120  * @config_svn:		a user-defined value that is used in key derivation
121  *
122  * SGX Enclave Control Structure (SECS) is a special enclave page that is not
123  * visible in the address space. In fact, this structure defines the address
124  * range and other global attributes for the enclave and it is the first EPC
125  * page created for any enclave. It is moved from a temporary buffer to an EPC
126  * by the means of ENCLS[ECREATE] function.
127  */
128 struct sgx_secs {
129 	u64 size;
130 	u64 base;
131 	u32 ssa_frame_size;
132 	u32 miscselect;
133 	u8  reserved1[24];
134 	u64 attributes;
135 	u64 xfrm;
136 	u32 mrenclave[8];
137 	u8  reserved2[32];
138 	u32 mrsigner[8];
139 	u8  reserved3[32];
140 	u32 config_id[16];
141 	u16 isv_prod_id;
142 	u16 isv_svn;
143 	u16 config_svn;
144 	u8  reserved4[3834];
145 } __packed;
146 
147 /**
148  * enum sgx_tcs_flags - execution flags for TCS
149  * %SGX_TCS_DBGOPTIN:	If enabled allows single-stepping and breakpoints
150  *			inside an enclave. It is cleared by EADD but can
151  *			be set later with EDBGWR.
152  */
153 enum sgx_tcs_flags {
154 	SGX_TCS_DBGOPTIN	= 0x01,
155 };
156 
157 #define SGX_TCS_RESERVED_MASK	GENMASK_ULL(63, 1)
158 #define SGX_TCS_RESERVED_SIZE	4024
159 
160 /**
161  * struct sgx_tcs - Thread Control Structure (TCS)
162  * @state:		used to mark an entered TCS
163  * @flags:		execution flags (cleared by EADD)
164  * @ssa_offset:		SSA stack offset relative to the enclave base
165  * @ssa_index:		the current SSA frame index (cleard by EADD)
166  * @nr_ssa_frames:	the number of frame in the SSA stack
167  * @entry_offset:	entry point offset relative to the enclave base
168  * @exit_addr:		address outside the enclave to exit on an exception or
169  *			interrupt
170  * @fs_offset:		offset relative to the enclave base to become FS
171  *			segment inside the enclave
172  * @gs_offset:		offset relative to the enclave base to become GS
173  *			segment inside the enclave
174  * @fs_limit:		size to become a new FS-limit (only 32-bit enclaves)
175  * @gs_limit:		size to become a new GS-limit (only 32-bit enclaves)
176  *
177  * Thread Control Structure (TCS) is an enclave page visible in its address
178  * space that defines an entry point inside the enclave. A thread enters inside
179  * an enclave by supplying address of TCS to ENCLU(EENTER). A TCS can be entered
180  * by only one thread at a time.
181  */
182 struct sgx_tcs {
183 	u64 state;
184 	u64 flags;
185 	u64 ssa_offset;
186 	u32 ssa_index;
187 	u32 nr_ssa_frames;
188 	u64 entry_offset;
189 	u64 exit_addr;
190 	u64 fs_offset;
191 	u64 gs_offset;
192 	u32 fs_limit;
193 	u32 gs_limit;
194 	u8  reserved[SGX_TCS_RESERVED_SIZE];
195 } __packed;
196 
197 /**
198  * struct sgx_pageinfo - an enclave page descriptor
199  * @addr:	address of the enclave page
200  * @contents:	pointer to the page contents
201  * @metadata:	pointer either to a SECINFO or PCMD instance
202  * @secs:	address of the SECS page
203  */
204 struct sgx_pageinfo {
205 	u64 addr;
206 	u64 contents;
207 	u64 metadata;
208 	u64 secs;
209 } __packed __aligned(32);
210 
211 
212 /**
213  * enum sgx_page_type - bits in the SECINFO flags defining the page type
214  * %SGX_PAGE_TYPE_SECS:	a SECS page
215  * %SGX_PAGE_TYPE_TCS:	a TCS page
216  * %SGX_PAGE_TYPE_REG:	a regular page
217  * %SGX_PAGE_TYPE_VA:	a VA page
218  * %SGX_PAGE_TYPE_TRIM:	a page in trimmed state
219  */
220 enum sgx_page_type {
221 	SGX_PAGE_TYPE_SECS,
222 	SGX_PAGE_TYPE_TCS,
223 	SGX_PAGE_TYPE_REG,
224 	SGX_PAGE_TYPE_VA,
225 	SGX_PAGE_TYPE_TRIM,
226 };
227 
228 #define SGX_NR_PAGE_TYPES	5
229 #define SGX_PAGE_TYPE_MASK	GENMASK(7, 0)
230 
231 /**
232  * enum sgx_secinfo_flags - the flags field in &struct sgx_secinfo
233  * %SGX_SECINFO_R:	allow read
234  * %SGX_SECINFO_W:	allow write
235  * %SGX_SECINFO_X:	allow execution
236  * %SGX_SECINFO_SECS:	a SECS page
237  * %SGX_SECINFO_TCS:	a TCS page
238  * %SGX_SECINFO_REG:	a regular page
239  * %SGX_SECINFO_VA:	a VA page
240  * %SGX_SECINFO_TRIM:	a page in trimmed state
241  */
242 enum sgx_secinfo_flags {
243 	SGX_SECINFO_R			= BIT(0),
244 	SGX_SECINFO_W			= BIT(1),
245 	SGX_SECINFO_X			= BIT(2),
246 	SGX_SECINFO_SECS		= (SGX_PAGE_TYPE_SECS << 8),
247 	SGX_SECINFO_TCS			= (SGX_PAGE_TYPE_TCS << 8),
248 	SGX_SECINFO_REG			= (SGX_PAGE_TYPE_REG << 8),
249 	SGX_SECINFO_VA			= (SGX_PAGE_TYPE_VA << 8),
250 	SGX_SECINFO_TRIM		= (SGX_PAGE_TYPE_TRIM << 8),
251 };
252 
253 #define SGX_SECINFO_PERMISSION_MASK	GENMASK_ULL(2, 0)
254 #define SGX_SECINFO_PAGE_TYPE_MASK	(SGX_PAGE_TYPE_MASK << 8)
255 #define SGX_SECINFO_RESERVED_MASK	~(SGX_SECINFO_PERMISSION_MASK | \
256 					  SGX_SECINFO_PAGE_TYPE_MASK)
257 
258 /**
259  * struct sgx_secinfo - describes attributes of an EPC page
260  * @flags:	permissions and type
261  *
262  * Used together with ENCLS leaves that add or modify an EPC page to an
263  * enclave to define page permissions and type.
264  */
265 struct sgx_secinfo {
266 	u64 flags;
267 	u8  reserved[56];
268 } __packed __aligned(64);
269 
270 #define SGX_PCMD_RESERVED_SIZE 40
271 
272 /**
273  * struct sgx_pcmd - Paging Crypto Metadata (PCMD)
274  * @enclave_id:	enclave identifier
275  * @mac:	MAC over PCMD, page contents and isvsvn
276  *
277  * PCMD is stored for every swapped page to the regular memory. When ELDU loads
278  * the page back it recalculates the MAC by using a isvsvn number stored in a
279  * VA page. Together these two structures bring integrity and rollback
280  * protection.
281  */
282 struct sgx_pcmd {
283 	struct sgx_secinfo secinfo;
284 	u64 enclave_id;
285 	u8  reserved[SGX_PCMD_RESERVED_SIZE];
286 	u8  mac[16];
287 } __packed __aligned(128);
288 
289 #define SGX_SIGSTRUCT_RESERVED1_SIZE 84
290 #define SGX_SIGSTRUCT_RESERVED2_SIZE 20
291 #define SGX_SIGSTRUCT_RESERVED3_SIZE 32
292 #define SGX_SIGSTRUCT_RESERVED4_SIZE 12
293 
294 /**
295  * struct sgx_sigstruct_header -  defines author of the enclave
296  * @header1:		constant byte string
297  * @vendor:		must be either 0x0000 or 0x8086
298  * @date:		YYYYMMDD in BCD
299  * @header2:		constant byte string
300  * @swdefined:		software defined value
301  */
302 struct sgx_sigstruct_header {
303 	u64 header1[2];
304 	u32 vendor;
305 	u32 date;
306 	u64 header2[2];
307 	u32 swdefined;
308 	u8  reserved1[84];
309 } __packed;
310 
311 /**
312  * struct sgx_sigstruct_body - defines contents of the enclave
313  * @miscselect:		additional information stored to an SSA frame
314  * @misc_mask:		required miscselect in SECS
315  * @attributes:		attributes for enclave
316  * @xfrm:		XSave-Feature Request Mask (subset of XCR0)
317  * @attributes_mask:	required attributes in SECS
318  * @xfrm_mask:		required XFRM in SECS
319  * @mrenclave:		SHA256-hash of the enclave contents
320  * @isvprodid:		a user-defined value that is used in key derivation
321  * @isvsvn:		a user-defined value that is used in key derivation
322  */
323 struct sgx_sigstruct_body {
324 	u32 miscselect;
325 	u32 misc_mask;
326 	u8  reserved2[20];
327 	u64 attributes;
328 	u64 xfrm;
329 	u64 attributes_mask;
330 	u64 xfrm_mask;
331 	u8  mrenclave[32];
332 	u8  reserved3[32];
333 	u16 isvprodid;
334 	u16 isvsvn;
335 } __packed;
336 
337 /**
338  * struct sgx_sigstruct - an enclave signature
339  * @header:		defines author of the enclave
340  * @modulus:		the modulus of the public key
341  * @exponent:		the exponent of the public key
342  * @signature:		the signature calculated over the fields except modulus,
343  * @body:		defines contents of the enclave
344  * @q1:			a value used in RSA signature verification
345  * @q2:			a value used in RSA signature verification
346  *
347  * Header and body are the parts that are actual signed. The remaining fields
348  * define the signature of the enclave.
349  */
350 struct sgx_sigstruct {
351 	struct sgx_sigstruct_header header;
352 	u8  modulus[SGX_MODULUS_SIZE];
353 	u32 exponent;
354 	u8  signature[SGX_MODULUS_SIZE];
355 	struct sgx_sigstruct_body body;
356 	u8  reserved4[12];
357 	u8  q1[SGX_MODULUS_SIZE];
358 	u8  q2[SGX_MODULUS_SIZE];
359 } __packed;
360 
361 #define SGX_LAUNCH_TOKEN_SIZE 304
362 
363 /*
364  * Do not put any hardware-defined SGX structure representations below this
365  * comment!
366  */
367 
368 #ifdef CONFIG_X86_SGX_KVM
369 int sgx_virt_ecreate(struct sgx_pageinfo *pageinfo, void __user *secs,
370 		     int *trapnr);
371 int sgx_virt_einit(void __user *sigstruct, void __user *token,
372 		   void __user *secs, u64 *lepubkeyhash, int *trapnr);
373 #endif
374 
375 int sgx_set_attribute(unsigned long *allowed_attributes,
376 		      unsigned int attribute_fd);
377 
378 #endif /* _ASM_X86_SGX_H */
379