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