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 */
encls_faulted(int ret)33 static 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 */
encls_failed(int ret)46 static 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. */
__ecreate(struct sgx_pageinfo * pginfo,void * secs)140 static 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. */
__eextend(void * secs,void * addr)146 static 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 */
__eadd(struct sgx_pageinfo * pginfo,void * addr)155 static 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. */
__einit(void * sigstruct,void * token,void * secs)161 static 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. */
__eremove(void * addr)167 static 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. */
__edbgwr(void * addr,unsigned long * data)173 static 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. */
__edbgrd(void * addr,unsigned long * data)179 static 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. */
__etrack(void * addr)185 static inline int __etrack(void *addr)
186 {
187 return __encls_ret_1(ETRACK, addr);
188 }
189
190 /* Load, verify, and unblock an EPC page. */
__eldu(struct sgx_pageinfo * pginfo,void * addr,void * va)191 static 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. */
__eblock(void * addr)198 static 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. */
__epa(void * addr)204 static 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. */
__ewb(struct sgx_pageinfo * pginfo,void * addr,void * va)212 static 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. */
__emodpr(struct sgx_secinfo * secinfo,void * addr)219 static 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. */
__emodt(struct sgx_secinfo * secinfo,void * addr)225 static 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. */
__eaug(struct sgx_pageinfo * pginfo,void * addr)231 static 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