xref: /linux/arch/x86/include/asm/sev.h (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * AMD Encrypted Register State Support
4  *
5  * Author: Joerg Roedel <jroedel@suse.de>
6  */
7 
8 #ifndef __ASM_ENCRYPTED_STATE_H
9 #define __ASM_ENCRYPTED_STATE_H
10 
11 #include <linux/types.h>
12 #include <linux/sev-guest.h>
13 
14 #include <asm/insn.h>
15 #include <asm/sev-common.h>
16 #include <asm/coco.h>
17 
18 #define GHCB_PROTOCOL_MIN	1ULL
19 #define GHCB_PROTOCOL_MAX	2ULL
20 #define GHCB_DEFAULT_USAGE	0ULL
21 
22 #define	VMGEXIT()			{ asm volatile("rep; vmmcall\n\r"); }
23 
24 struct boot_params;
25 
26 enum es_result {
27 	ES_OK,			/* All good */
28 	ES_UNSUPPORTED,		/* Requested operation not supported */
29 	ES_VMM_ERROR,		/* Unexpected state from the VMM */
30 	ES_DECODE_FAILED,	/* Instruction decoding failed */
31 	ES_EXCEPTION,		/* Instruction caused exception */
32 	ES_RETRY,		/* Retry instruction emulation */
33 };
34 
35 struct es_fault_info {
36 	unsigned long vector;
37 	unsigned long error_code;
38 	unsigned long cr2;
39 };
40 
41 struct pt_regs;
42 
43 /* ES instruction emulation context */
44 struct es_em_ctxt {
45 	struct pt_regs *regs;
46 	struct insn insn;
47 	struct es_fault_info fi;
48 };
49 
50 /*
51  * AMD SEV Confidential computing blob structure. The structure is
52  * defined in OVMF UEFI firmware header:
53  * https://github.com/tianocore/edk2/blob/master/OvmfPkg/Include/Guid/ConfidentialComputingSevSnpBlob.h
54  */
55 #define CC_BLOB_SEV_HDR_MAGIC	0x45444d41
56 struct cc_blob_sev_info {
57 	u32 magic;
58 	u16 version;
59 	u16 reserved;
60 	u64 secrets_phys;
61 	u32 secrets_len;
62 	u32 rsvd1;
63 	u64 cpuid_phys;
64 	u32 cpuid_len;
65 	u32 rsvd2;
66 } __packed;
67 
68 void do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code);
69 
70 static inline u64 lower_bits(u64 val, unsigned int bits)
71 {
72 	u64 mask = (1ULL << bits) - 1;
73 
74 	return (val & mask);
75 }
76 
77 struct real_mode_header;
78 enum stack_type;
79 
80 /* Early IDT entry points for #VC handler */
81 extern void vc_no_ghcb(void);
82 extern void vc_boot_ghcb(void);
83 extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
84 
85 /* PVALIDATE return codes */
86 #define PVALIDATE_FAIL_SIZEMISMATCH	6
87 
88 /* Software defined (when rFlags.CF = 1) */
89 #define PVALIDATE_FAIL_NOUPDATE		255
90 
91 /* RMUPDATE detected 4K page and 2MB page overlap. */
92 #define RMPUPDATE_FAIL_OVERLAP		4
93 
94 /* PSMASH failed due to concurrent access by another CPU */
95 #define PSMASH_FAIL_INUSE		3
96 
97 /* RMP page size */
98 #define RMP_PG_SIZE_4K			0
99 #define RMP_PG_SIZE_2M			1
100 #define RMP_TO_PG_LEVEL(level)		(((level) == RMP_PG_SIZE_4K) ? PG_LEVEL_4K : PG_LEVEL_2M)
101 #define PG_LEVEL_TO_RMP(level)		(((level) == PG_LEVEL_4K) ? RMP_PG_SIZE_4K : RMP_PG_SIZE_2M)
102 
103 struct rmp_state {
104 	u64 gpa;
105 	u8 assigned;
106 	u8 pagesize;
107 	u8 immutable;
108 	u8 rsvd;
109 	u32 asid;
110 } __packed;
111 
112 #define RMPADJUST_VMSA_PAGE_BIT		BIT(16)
113 
114 /* SNP Guest message request */
115 struct snp_req_data {
116 	unsigned long req_gpa;
117 	unsigned long resp_gpa;
118 	unsigned long data_gpa;
119 	unsigned int data_npages;
120 };
121 
122 #define MAX_AUTHTAG_LEN		32
123 
124 /* See SNP spec SNP_GUEST_REQUEST section for the structure */
125 enum msg_type {
126 	SNP_MSG_TYPE_INVALID = 0,
127 	SNP_MSG_CPUID_REQ,
128 	SNP_MSG_CPUID_RSP,
129 	SNP_MSG_KEY_REQ,
130 	SNP_MSG_KEY_RSP,
131 	SNP_MSG_REPORT_REQ,
132 	SNP_MSG_REPORT_RSP,
133 	SNP_MSG_EXPORT_REQ,
134 	SNP_MSG_EXPORT_RSP,
135 	SNP_MSG_IMPORT_REQ,
136 	SNP_MSG_IMPORT_RSP,
137 	SNP_MSG_ABSORB_REQ,
138 	SNP_MSG_ABSORB_RSP,
139 	SNP_MSG_VMRK_REQ,
140 	SNP_MSG_VMRK_RSP,
141 
142 	SNP_MSG_TYPE_MAX
143 };
144 
145 enum aead_algo {
146 	SNP_AEAD_INVALID,
147 	SNP_AEAD_AES_256_GCM,
148 };
149 
150 struct snp_guest_msg_hdr {
151 	u8 authtag[MAX_AUTHTAG_LEN];
152 	u64 msg_seqno;
153 	u8 rsvd1[8];
154 	u8 algo;
155 	u8 hdr_version;
156 	u16 hdr_sz;
157 	u8 msg_type;
158 	u8 msg_version;
159 	u16 msg_sz;
160 	u32 rsvd2;
161 	u8 msg_vmpck;
162 	u8 rsvd3[35];
163 } __packed;
164 
165 struct snp_guest_msg {
166 	struct snp_guest_msg_hdr hdr;
167 	u8 payload[4000];
168 } __packed;
169 
170 struct sev_guest_platform_data {
171 	u64 secrets_gpa;
172 };
173 
174 /*
175  * The secrets page contains 96-bytes of reserved field that can be used by
176  * the guest OS. The guest OS uses the area to save the message sequence
177  * number for each VMPCK.
178  *
179  * See the GHCB spec section Secret page layout for the format for this area.
180  */
181 struct secrets_os_area {
182 	u32 msg_seqno_0;
183 	u32 msg_seqno_1;
184 	u32 msg_seqno_2;
185 	u32 msg_seqno_3;
186 	u64 ap_jump_table_pa;
187 	u8 rsvd[40];
188 	u8 guest_usage[32];
189 } __packed;
190 
191 #define VMPCK_KEY_LEN		32
192 
193 /* See the SNP spec version 0.9 for secrets page format */
194 struct snp_secrets_page {
195 	u32 version;
196 	u32 imien	: 1,
197 	    rsvd1	: 31;
198 	u32 fms;
199 	u32 rsvd2;
200 	u8 gosvw[16];
201 	u8 vmpck0[VMPCK_KEY_LEN];
202 	u8 vmpck1[VMPCK_KEY_LEN];
203 	u8 vmpck2[VMPCK_KEY_LEN];
204 	u8 vmpck3[VMPCK_KEY_LEN];
205 	struct secrets_os_area os_area;
206 
207 	u8 vmsa_tweak_bitmap[64];
208 
209 	/* SVSM fields */
210 	u64 svsm_base;
211 	u64 svsm_size;
212 	u64 svsm_caa;
213 	u32 svsm_max_version;
214 	u8 svsm_guest_vmpl;
215 	u8 rsvd3[3];
216 
217 	/* Remainder of page */
218 	u8 rsvd4[3744];
219 } __packed;
220 
221 /*
222  * The SVSM Calling Area (CA) related structures.
223  */
224 struct svsm_ca {
225 	u8 call_pending;
226 	u8 mem_available;
227 	u8 rsvd1[6];
228 
229 	u8 svsm_buffer[PAGE_SIZE - 8];
230 };
231 
232 #define SVSM_SUCCESS				0
233 #define SVSM_ERR_INCOMPLETE			0x80000000
234 #define SVSM_ERR_UNSUPPORTED_PROTOCOL		0x80000001
235 #define SVSM_ERR_UNSUPPORTED_CALL		0x80000002
236 #define SVSM_ERR_INVALID_ADDRESS		0x80000003
237 #define SVSM_ERR_INVALID_FORMAT			0x80000004
238 #define SVSM_ERR_INVALID_PARAMETER		0x80000005
239 #define SVSM_ERR_INVALID_REQUEST		0x80000006
240 #define SVSM_ERR_BUSY				0x80000007
241 #define SVSM_PVALIDATE_FAIL_SIZEMISMATCH	0x80001006
242 
243 /*
244  * The SVSM PVALIDATE related structures
245  */
246 struct svsm_pvalidate_entry {
247 	u64 page_size		: 2,
248 	    action		: 1,
249 	    ignore_cf		: 1,
250 	    rsvd		: 8,
251 	    pfn			: 52;
252 };
253 
254 struct svsm_pvalidate_call {
255 	u16 num_entries;
256 	u16 cur_index;
257 
258 	u8 rsvd1[4];
259 
260 	struct svsm_pvalidate_entry entry[];
261 };
262 
263 #define SVSM_PVALIDATE_MAX_COUNT	((sizeof_field(struct svsm_ca, svsm_buffer) -		\
264 					  offsetof(struct svsm_pvalidate_call, entry)) /	\
265 					 sizeof(struct svsm_pvalidate_entry))
266 
267 /*
268  * The SVSM Attestation related structures
269  */
270 struct svsm_loc_entry {
271 	u64 pa;
272 	u32 len;
273 	u8 rsvd[4];
274 };
275 
276 struct svsm_attest_call {
277 	struct svsm_loc_entry report_buf;
278 	struct svsm_loc_entry nonce;
279 	struct svsm_loc_entry manifest_buf;
280 	struct svsm_loc_entry certificates_buf;
281 
282 	/* For attesting a single service */
283 	u8 service_guid[16];
284 	u32 service_manifest_ver;
285 	u8 rsvd[4];
286 };
287 
288 /*
289  * SVSM protocol structure
290  */
291 struct svsm_call {
292 	struct svsm_ca *caa;
293 	u64 rax;
294 	u64 rcx;
295 	u64 rdx;
296 	u64 r8;
297 	u64 r9;
298 	u64 rax_out;
299 	u64 rcx_out;
300 	u64 rdx_out;
301 	u64 r8_out;
302 	u64 r9_out;
303 };
304 
305 #define SVSM_CORE_CALL(x)		((0ULL << 32) | (x))
306 #define SVSM_CORE_REMAP_CA		0
307 #define SVSM_CORE_PVALIDATE		1
308 #define SVSM_CORE_CREATE_VCPU		2
309 #define SVSM_CORE_DELETE_VCPU		3
310 
311 #define SVSM_ATTEST_CALL(x)		((1ULL << 32) | (x))
312 #define SVSM_ATTEST_SERVICES		0
313 #define SVSM_ATTEST_SINGLE_SERVICE	1
314 
315 #ifdef CONFIG_AMD_MEM_ENCRYPT
316 
317 extern u8 snp_vmpl;
318 
319 extern void __sev_es_ist_enter(struct pt_regs *regs);
320 extern void __sev_es_ist_exit(void);
321 static __always_inline void sev_es_ist_enter(struct pt_regs *regs)
322 {
323 	if (cc_vendor == CC_VENDOR_AMD &&
324 	    cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
325 		__sev_es_ist_enter(regs);
326 }
327 static __always_inline void sev_es_ist_exit(void)
328 {
329 	if (cc_vendor == CC_VENDOR_AMD &&
330 	    cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
331 		__sev_es_ist_exit();
332 }
333 extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh);
334 extern void __sev_es_nmi_complete(void);
335 static __always_inline void sev_es_nmi_complete(void)
336 {
337 	if (cc_vendor == CC_VENDOR_AMD &&
338 	    cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
339 		__sev_es_nmi_complete();
340 }
341 extern int __init sev_es_efi_map_ghcbs(pgd_t *pgd);
342 extern void sev_enable(struct boot_params *bp);
343 
344 /*
345  * RMPADJUST modifies the RMP permissions of a page of a lesser-
346  * privileged (numerically higher) VMPL.
347  *
348  * If the guest is running at a higher-privilege than the privilege
349  * level the instruction is targeting, the instruction will succeed,
350  * otherwise, it will fail.
351  */
352 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs)
353 {
354 	int rc;
355 
356 	/* "rmpadjust" mnemonic support in binutils 2.36 and newer */
357 	asm volatile(".byte 0xF3,0x0F,0x01,0xFE\n\t"
358 		     : "=a"(rc)
359 		     : "a"(vaddr), "c"(rmp_psize), "d"(attrs)
360 		     : "memory", "cc");
361 
362 	return rc;
363 }
364 static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate)
365 {
366 	bool no_rmpupdate;
367 	int rc;
368 
369 	/* "pvalidate" mnemonic support in binutils 2.36 and newer */
370 	asm volatile(".byte 0xF2, 0x0F, 0x01, 0xFF\n\t"
371 		     CC_SET(c)
372 		     : CC_OUT(c) (no_rmpupdate), "=a"(rc)
373 		     : "a"(vaddr), "c"(rmp_psize), "d"(validate)
374 		     : "memory", "cc");
375 
376 	if (no_rmpupdate)
377 		return PVALIDATE_FAIL_NOUPDATE;
378 
379 	return rc;
380 }
381 
382 struct snp_guest_request_ioctl;
383 
384 void setup_ghcb(void);
385 void early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr,
386 				  unsigned long npages);
387 void early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr,
388 				 unsigned long npages);
389 void snp_set_memory_shared(unsigned long vaddr, unsigned long npages);
390 void snp_set_memory_private(unsigned long vaddr, unsigned long npages);
391 void snp_set_wakeup_secondary_cpu(void);
392 bool snp_init(struct boot_params *bp);
393 void __noreturn snp_abort(void);
394 void snp_dmi_setup(void);
395 int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio);
396 int snp_issue_svsm_attest_req(u64 call_id, struct svsm_call *call, struct svsm_attest_call *input);
397 void snp_accept_memory(phys_addr_t start, phys_addr_t end);
398 u64 snp_get_unsupported_features(u64 status);
399 u64 sev_get_status(void);
400 void sev_show_status(void);
401 void snp_update_svsm_ca(void);
402 
403 #else	/* !CONFIG_AMD_MEM_ENCRYPT */
404 
405 #define snp_vmpl 0
406 static inline void sev_es_ist_enter(struct pt_regs *regs) { }
407 static inline void sev_es_ist_exit(void) { }
408 static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; }
409 static inline void sev_es_nmi_complete(void) { }
410 static inline int sev_es_efi_map_ghcbs(pgd_t *pgd) { return 0; }
411 static inline void sev_enable(struct boot_params *bp) { }
412 static inline int pvalidate(unsigned long vaddr, bool rmp_psize, bool validate) { return 0; }
413 static inline int rmpadjust(unsigned long vaddr, bool rmp_psize, unsigned long attrs) { return 0; }
414 static inline void setup_ghcb(void) { }
415 static inline void __init
416 early_snp_set_memory_private(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
417 static inline void __init
418 early_snp_set_memory_shared(unsigned long vaddr, unsigned long paddr, unsigned long npages) { }
419 static inline void snp_set_memory_shared(unsigned long vaddr, unsigned long npages) { }
420 static inline void snp_set_memory_private(unsigned long vaddr, unsigned long npages) { }
421 static inline void snp_set_wakeup_secondary_cpu(void) { }
422 static inline bool snp_init(struct boot_params *bp) { return false; }
423 static inline void snp_abort(void) { }
424 static inline void snp_dmi_setup(void) { }
425 static inline int snp_issue_guest_request(u64 exit_code, struct snp_req_data *input, struct snp_guest_request_ioctl *rio)
426 {
427 	return -ENOTTY;
428 }
429 static inline int snp_issue_svsm_attest_req(u64 call_id, struct svsm_call *call, struct svsm_attest_call *input)
430 {
431 	return -ENOTTY;
432 }
433 static inline void snp_accept_memory(phys_addr_t start, phys_addr_t end) { }
434 static inline u64 snp_get_unsupported_features(u64 status) { return 0; }
435 static inline u64 sev_get_status(void) { return 0; }
436 static inline void sev_show_status(void) { }
437 static inline void snp_update_svsm_ca(void) { }
438 
439 #endif	/* CONFIG_AMD_MEM_ENCRYPT */
440 
441 #ifdef CONFIG_KVM_AMD_SEV
442 bool snp_probe_rmptable_info(void);
443 int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level);
444 void snp_dump_hva_rmpentry(unsigned long address);
445 int psmash(u64 pfn);
446 int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid, bool immutable);
447 int rmp_make_shared(u64 pfn, enum pg_level level);
448 void snp_leak_pages(u64 pfn, unsigned int npages);
449 void kdump_sev_callback(void);
450 void snp_fixup_e820_tables(void);
451 #else
452 static inline bool snp_probe_rmptable_info(void) { return false; }
453 static inline int snp_lookup_rmpentry(u64 pfn, bool *assigned, int *level) { return -ENODEV; }
454 static inline void snp_dump_hva_rmpentry(unsigned long address) {}
455 static inline int psmash(u64 pfn) { return -ENODEV; }
456 static inline int rmp_make_private(u64 pfn, u64 gpa, enum pg_level level, u32 asid,
457 				   bool immutable)
458 {
459 	return -ENODEV;
460 }
461 static inline int rmp_make_shared(u64 pfn, enum pg_level level) { return -ENODEV; }
462 static inline void snp_leak_pages(u64 pfn, unsigned int npages) {}
463 static inline void kdump_sev_callback(void) { }
464 static inline void snp_fixup_e820_tables(void) {}
465 #endif
466 
467 #endif
468