xref: /freebsd/contrib/processor-trace/libipt/internal/include/pt_insn.h (revision 85f87cf491bec6f90948a85b10f5523ea24db9e3)
1 /*
2  * Copyright (c) 2016-2019, Intel Corporation
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  *  * Redistributions of source code must retain the above copyright notice,
8  *    this list of conditions and the following disclaimer.
9  *  * Redistributions in binary form must reproduce the above copyright notice,
10  *    this list of conditions and the following disclaimer in the documentation
11  *    and/or other materials provided with the distribution.
12  *  * Neither the name of Intel Corporation nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef PT_INSN_H
30 #define PT_INSN_H
31 
32 #include <inttypes.h>
33 
34 #include "intel-pt.h"
35 
36 struct pt_insn_ext;
37 
38 
39 /* A finer-grain classification of instructions used internally. */
40 typedef enum {
41 	PTI_INST_INVALID,
42 
43 	PTI_INST_CALL_9A,
44 	PTI_INST_CALL_FFr3,
45 	PTI_INST_CALL_FFr2,
46 	PTI_INST_CALL_E8,
47 	PTI_INST_INT,
48 
49 	PTI_INST_INT3,
50 	PTI_INST_INT1,
51 	PTI_INST_INTO,
52 	PTI_INST_IRET,	/* includes IRETD and IRETQ (EOSZ determines) */
53 
54 	PTI_INST_JMP_E9,
55 	PTI_INST_JMP_EB,
56 	PTI_INST_JMP_EA,
57 	PTI_INST_JMP_FFr5,	/* REXW? */
58 	PTI_INST_JMP_FFr4,
59 	PTI_INST_JCC,
60 	PTI_INST_JrCXZ,
61 	PTI_INST_LOOP,
62 	PTI_INST_LOOPE,	/* aka Z */
63 	PTI_INST_LOOPNE,	/* aka NE */
64 
65 	PTI_INST_MOV_CR3,
66 
67 	PTI_INST_RET_C3,
68 	PTI_INST_RET_C2,
69 	PTI_INST_RET_CB,
70 	PTI_INST_RET_CA,
71 
72 	PTI_INST_SYSCALL,
73 	PTI_INST_SYSENTER,
74 	PTI_INST_SYSEXIT,
75 	PTI_INST_SYSRET,
76 
77 	PTI_INST_VMLAUNCH,
78 	PTI_INST_VMRESUME,
79 	PTI_INST_VMCALL,
80 	PTI_INST_VMPTRLD,
81 
82 	PTI_INST_PTWRITE,
83 
84 	PTI_INST_LAST
85 } pti_inst_enum_t;
86 
87 /* Information about an instruction we need internally in addition to the
88  * information provided in struct pt_insn.
89  */
90 struct pt_insn_ext {
91 	/* A more detailed instruction class. */
92 	pti_inst_enum_t iclass;
93 
94 	/* Instruction-specific information. */
95 	union {
96 		/* For branch instructions. */
97 		struct {
98 			/* The branch displacement.
99 			 *
100 			 * This is only valid for direct calls/jumps.
101 			 *
102 			 * The displacement is applied to the address of the
103 			 * instruction following the branch.
104 			 */
105 			int32_t displacement;
106 
107 			/* A flag saying whether the branch is direct.
108 			 *
109 			 *   non-zero: direct
110 			 *   zero:     indirect
111 			 *
112 			 * This is expected to go away someday when we extend
113 			 * enum pt_insn_class to distinguish direct and indirect
114 			 * branches.
115 			 */
116 			uint8_t is_direct;
117 		} branch;
118 	} variant;
119 };
120 
121 
122 /* Check if the instruction @insn/@iext changes the current privilege level.
123  *
124  * Returns non-zero if it does, zero if it doesn't (or @insn/@iext is NULL).
125  */
126 extern int pt_insn_changes_cpl(const struct pt_insn *insn,
127 			       const struct pt_insn_ext *iext);
128 
129 /* Check if the instruction @insn/@iext changes CR3.
130  *
131  * Returns non-zero if it does, zero if it doesn't (or @insn/@iext is NULL).
132  */
133 extern int pt_insn_changes_cr3(const struct pt_insn *insn,
134 			       const struct pt_insn_ext *iext);
135 
136 /* Check if the instruction @insn/@iext is a (near or far) branch.
137  *
138  * Returns non-zero if it is, zero if it isn't (or @insn/@iext is NULL).
139  */
140 extern int pt_insn_is_branch(const struct pt_insn *insn,
141 			     const struct pt_insn_ext *iext);
142 
143 /* Check if the instruction @insn/@iext is a far branch.
144  *
145  * Returns non-zero if it is, zero if it isn't (or @insn/@iext is NULL).
146  */
147 extern int pt_insn_is_far_branch(const struct pt_insn *insn,
148 				 const struct pt_insn_ext *iext);
149 
150 /* Check if the instruction @insn/@iext binds to a PIP packet.
151  *
152  * Returns non-zero if it does, zero if it doesn't (or @insn/@iext is NULL).
153  */
154 extern int pt_insn_binds_to_pip(const struct pt_insn *insn,
155 				const struct pt_insn_ext *iext);
156 
157 /* Check if the instruction @insn/@iext binds to a VMCS packet.
158  *
159  * Returns non-zero if it does, zero if it doesn't (or @insn/@iext is NULL).
160  */
161 extern int pt_insn_binds_to_vmcs(const struct pt_insn *insn,
162 				 const struct pt_insn_ext *iext);
163 
164 /* Check if the instruction @insn/@iext is a ptwrite instruction.
165  *
166  * Returns non-zero if it is, zero if it isn't (or @insn/@iext is NULL).
167  */
168 extern int pt_insn_is_ptwrite(const struct pt_insn *insn,
169 			      const struct pt_insn_ext *iext);
170 
171 /* Determine the IP of the next instruction.
172  *
173  * Tries to determine the IP of the next instruction without using trace and
174  * provides it in @ip unless @ip is NULL.
175  *
176  * Returns zero on success, a negative error code otherwise.
177  * Returns -pte_bad_query if the IP can't be determined.
178  * Returns -pte_internal if @insn or @iext is NULL.
179  */
180 extern int pt_insn_next_ip(uint64_t *ip, const struct pt_insn *insn,
181 			   const struct pt_insn_ext *iext);
182 
183 /* Decode and analyze one instruction.
184  *
185  * Decodes the instructruction at @insn->ip in @insn->mode into @insn and @iext.
186  *
187  * If the instruction can not be decoded using a single memory read in a single
188  * section, sets @insn->truncated and reads the missing bytes from one or more
189  * other sections until either the instruction can be decoded or we're sure it
190  * is invalid.
191  *
192  * Returns the size in bytes on success, a negative error code otherwise.
193  * Returns -pte_bad_insn if the instruction could not be decoded.
194  */
195 extern int pt_insn_decode(struct pt_insn *insn, struct pt_insn_ext *iext,
196 			  struct pt_image *image, const struct pt_asid *asid);
197 
198 /* Determine if a range of instructions is contiguous.
199  *
200  * Try to proceed from IP @begin to IP @end in @asid without using trace.
201  *
202  * Returns a positive integer if we reach @end from @begin.
203  * Returns zero if we couldn't reach @end within @nsteps steps.
204  * Returns a negative error code otherwise.
205  */
206 extern int pt_insn_range_is_contiguous(uint64_t begin, uint64_t end,
207 				       enum pt_exec_mode mode,
208 				       struct pt_image *image,
209 				       const struct pt_asid *asid,
210 				       size_t nsteps);
211 
212 #endif /* PT_INSN_H */
213