1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _X86_ENCLS_H
3#define _X86_ENCLS_H
4
5#include <linux/bitops.h>
6#include <linux/err.h>
7#include <linux/io.h>
8#include <linux/rwsem.h>
9#include <linux/types.h>
10#include <asm/asm.h>
11#include <asm/traps.h>
12#include "sgx.h"
13
14/* Retrieve the encoded trapnr from the specified return code. */
15#define ENCLS_TRAPNR(r) ((r) & ~SGX_ENCLS_FAULT_FLAG)
16
17/* Issue a WARN() about an ENCLS function. */
18#define ENCLS_WARN(r, name) { \
19 do { \
20 int _r = (r); \
21 WARN_ONCE(_r, "%s returned %d (0x%x)\n", (name), _r, _r); \
22 } while (0); \
23}
24
25/*
26 * encls_faulted() - Check if an ENCLS leaf faulted given an error code
27 * @ret: the return value of an ENCLS leaf function call
28 *
29 * Return:
30 * - true: ENCLS leaf faulted.
31 * - false: Otherwise.
32 */
33static inline bool encls_faulted(int ret)
34{
35 return ret & SGX_ENCLS_FAULT_FLAG;
36}
37
38/**
39 * encls_failed() - Check if an ENCLS function failed
40 * @ret: the return value of an ENCLS function call
41 *
42 * Check if an ENCLS function failed. This happens when the function causes a
43 * fault that is not caused by an EPCM conflict or when the function returns a
44 * non-zero value.
45 */
46static inline bool encls_failed(int ret)
47{
48 if (encls_faulted(ret))
49 return ENCLS_TRAPNR(ret) != X86_TRAP_PF;
50
51 return !!ret;
52}
53
54/**
55 * __encls_ret_N - encode an ENCLS function that returns an error code in EAX
56 * @rax: function number
57 * @inputs: asm inputs for the function
58 *
59 * Emit assembly for an ENCLS function that returns an error code, e.g. EREMOVE.
60 * And because SGX isn't complex enough as it is, function that return an error
61 * code also modify flags.
62 *
63 * Return:
64 * 0 on success,
65 * SGX error code on failure
66 */
67#define __encls_ret_N(rax, inputs...) \
68 ({ \
69 int ret; \
70 asm volatile( \
71 "1: .byte 0x0f, 0x01, 0xcf;\n\t" \
72 "2:\n" \
73 _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX) \
74 : "=a"(ret) \
75 : "a"(rax), inputs \
76 : "memory", "cc"); \
77 ret; \
78 })
79
80#define __encls_ret_1(rax, rcx) \
81 ({ \
82 __encls_ret_N(rax, "c"(rcx)); \
83 })
84
85#define __encls_ret_2(rax, rbx, rcx) \
86 ({ \
87 __encls_ret_N(rax, "b"(rbx), "c"(rcx)); \
88 })
89
90#define __encls_ret_3(rax, rbx, rcx, rdx) \
91 ({ \
92 __encls_ret_N(rax, "b"(rbx), "c"(rcx), "d"(rdx)); \
93 })
94
95/**
96 * __encls_N - encode an ENCLS function that doesn't return an error code
97 * @rax: function number
98 * @rbx_out: optional output variable
99 * @inputs: asm inputs for the function
100 *
101 * Emit assembly for an ENCLS function that does not return an error code, e.g.
102 * ECREATE. Leaves without error codes either succeed or fault. @rbx_out is an
103 * optional parameter for use by EDGBRD, which returns the requested value in
104 * RBX.
105 *
106 * Return:
107 * 0 on success,
108 * trapnr with SGX_ENCLS_FAULT_FLAG set on fault
109 */
110#define __encls_N(rax, rbx_out, inputs...) \
111 ({ \
112 int ret; \
113 asm volatile( \
114 "1: .byte 0x0f, 0x01, 0xcf;\n\t" \
115 " xor %%eax,%%eax;\n" \
116 "2:\n" \
117 _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_SGX) \
118 : "=a"(ret), "=b"(rbx_out) \
119 : "a"(rax), inputs \
120 : "memory"); \
121 ret; \
122 })
123
124#define __encls_2(rax, rbx, rcx) \
125 ({ \
126 unsigned long ign_rbx_out; \
127 __encls_N(rax, ign_rbx_out, "b"(rbx), "c"(rcx)); \
128 })
129
130#define __encls_1_1(rax, data, rcx) \
131 ({ \
132 unsigned long rbx_out; \
133 int ret = __encls_N(rax, rbx_out, "c"(rcx)); \
134 if (!ret) \
135 data = rbx_out; \
136 ret; \
137 })
138
139/* Initialize an EPC page into an SGX Enclave Control Structure (SECS) page. */
140static inline int __ecreate(struct sgx_pageinfo *pginfo, void *secs)
141{
142 return __encls_2(ECREATE, pginfo, secs);
143}
144
145/* Hash a 256 byte region of an enclave page to SECS:MRENCLAVE. */
146static inline int __eextend(void *secs, void *addr)
147{
148 return __encls_2(EEXTEND, secs, addr);
149}
150
151/*
152 * Associate an EPC page to an enclave either as a REG or TCS page
153 * populated with the provided data.
154 */
155static inline int __eadd(struct sgx_pageinfo *pginfo, void *addr)
156{
157 return __encls_2(EADD, pginfo, addr);
158}
159
160/* Finalize enclave build, initialize enclave for user code execution. */
161static inline int __einit(void *sigstruct, void *token, void *secs)
162{
163 return __encls_ret_3(EINIT, sigstruct, secs, token);
164}
165
166/* Disassociate EPC page from its enclave and mark it as unused. */
167static inline int __eremove(void *addr)
168{
169 return __encls_ret_1(EREMOVE, addr);
170}
171
172/* Copy data to an EPC page belonging to a debug enclave. */
173static inline int __edbgwr(void *addr, unsigned long *data)
174{
175 return __encls_2(EDGBWR, *data, addr);
176}
177
178/* Copy data from an EPC page belonging to a debug enclave. */
179static inline int __edbgrd(void *addr, unsigned long *data)
180{
181 return __encls_1_1(EDGBRD, *data, addr);
182}
183
184/* Track that software has completed the required TLB address clears. */
185static inline int __etrack(void *addr)
186{
187 return __encls_ret_1(ETRACK, addr);
188}
189
190/* Load, verify, and unblock an EPC page. */
191static inline int __eldu(struct sgx_pageinfo *pginfo, void *addr,
192 void *va)
193{
194 return __encls_ret_3(ELDU, pginfo, addr, va);
195}
196
197/* Make EPC page inaccessible to enclave, ready to be written to memory. */
198static inline int __eblock(void *addr)
199{
200 return __encls_ret_1(EBLOCK, addr);
201}
202
203/* Initialize an EPC page into a Version Array (VA) page. */
204static inline int __epa(void *addr)
205{
206 unsigned long rbx = SGX_PAGE_TYPE_VA;
207
208 return __encls_2(EPA, rbx, addr);
209}
210
211/* Invalidate an EPC page and write it out to main memory. */
212static inline int __ewb(struct sgx_pageinfo *pginfo, void *addr,
213 void *va)
214{
215 return __encls_ret_3(EWB, pginfo, addr, va);
216}
217
218/* Restrict the EPCM permissions of an EPC page. */
219static inline int __emodpr(struct sgx_secinfo *secinfo, void *addr)
220{
221 return __encls_ret_2(EMODPR, secinfo, addr);
222}
223
224/* Change the type of an EPC page. */
225static inline int __emodt(struct sgx_secinfo *secinfo, void *addr)
226{
227 return __encls_ret_2(EMODT, secinfo, addr);
228}
229
230/* Zero a page of EPC memory and add it to an initialized enclave. */
231static inline int __eaug(struct sgx_pageinfo *pginfo, void *addr)
232{
233 return __encls_2(EAUG, pginfo, addr);
234}
235
236#endif /* _X86_ENCLS_H */
237

source code of linux/arch/x86/kernel/cpu/sgx/encls.h