xref: /freebsd/lib/libproc/proc_regs.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2010 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * This software was developed by Rui Paulo under sponsorship from the
8  * FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/types.h>
36 #include <sys/ptrace.h>
37 
38 #include <err.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <errno.h>
42 
43 #include "_libproc.h"
44 
45 int
46 proc_regget(struct proc_handle *phdl, proc_reg_t reg, unsigned long *regvalue)
47 {
48 	struct reg regs;
49 
50 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
51 	    phdl->status == PS_IDLE) {
52 		errno = ENOENT;
53 		return (-1);
54 	}
55 	memset(&regs, 0, sizeof(regs));
56 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
57 		return (-1);
58 	switch (reg) {
59 	case REG_PC:
60 #if defined(__aarch64__)
61 		*regvalue = regs.elr;
62 #elif defined(__amd64__)
63 		*regvalue = regs.r_rip;
64 #elif defined(__arm__)
65 		*regvalue = regs.r_pc;
66 #elif defined(__i386__)
67 		*regvalue = regs.r_eip;
68 #elif defined(__mips__)
69 		*regvalue = regs.r_regs[PC];
70 #elif defined(__powerpc__)
71 		*regvalue = regs.pc;
72 #elif defined(__riscv)
73 		*regvalue = regs.sepc;
74 #endif
75 		break;
76 	case REG_SP:
77 #if defined(__aarch64__)
78 		*regvalue = regs.sp;
79 #elif defined(__amd64__)
80 		*regvalue = regs.r_rsp;
81 #elif defined(__arm__)
82 		*regvalue = regs.r_sp;
83 #elif defined(__i386__)
84 		*regvalue = regs.r_esp;
85 #elif defined(__mips__)
86 		*regvalue = regs.r_regs[SP];
87 #elif defined(__powerpc__)
88 		*regvalue = regs.fixreg[1];
89 #elif defined(__riscv)
90 		*regvalue = regs.sp;
91 #endif
92 		break;
93 	default:
94 		DPRINTFX("ERROR: no support for reg number %d", reg);
95 		return (-1);
96 	}
97 
98 	return (0);
99 }
100 
101 int
102 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
103 {
104 	struct reg regs;
105 
106 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
107 	    phdl->status == PS_IDLE) {
108 		errno = ENOENT;
109 		return (-1);
110 	}
111 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
112 		return (-1);
113 	switch (reg) {
114 	case REG_PC:
115 #if defined(__aarch64__)
116 		regs.elr = regvalue;
117 #elif defined(__amd64__)
118 		regs.r_rip = regvalue;
119 #elif defined(__arm__)
120 		regs.r_pc = regvalue;
121 #elif defined(__i386__)
122 		regs.r_eip = regvalue;
123 #elif defined(__mips__)
124 		regs.r_regs[PC] = regvalue;
125 #elif defined(__powerpc__)
126 		regs.pc = regvalue;
127 #elif defined(__riscv)
128 		regs.sepc = regvalue;
129 #endif
130 		break;
131 	case REG_SP:
132 #if defined(__aarch64__)
133 		regs.sp = regvalue;
134 #elif defined(__amd64__)
135 		regs.r_rsp = regvalue;
136 #elif defined(__arm__)
137 		regs.r_sp = regvalue;
138 #elif defined(__i386__)
139 		regs.r_esp = regvalue;
140 #elif defined(__mips__)
141 		regs.r_regs[PC] = regvalue;
142 #elif defined(__powerpc__)
143 		regs.fixreg[1] = regvalue;
144 #elif defined(__riscv)
145 		regs.sp = regvalue;
146 #endif
147 		break;
148 	default:
149 		DPRINTFX("ERROR: no support for reg number %d", reg);
150 		return (-1);
151 	}
152 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
153 		return (-1);
154 
155 	return (0);
156 }
157