xref: /freebsd/lib/libproc/proc_regs.c (revision ccfd87fe2ac0e2e6aeb1911a7d7cce6712a8564f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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(__powerpc__)
69 		*regvalue = regs.pc;
70 #elif defined(__riscv)
71 		*regvalue = regs.sepc;
72 #endif
73 		break;
74 	case REG_SP:
75 #if defined(__aarch64__)
76 		*regvalue = regs.sp;
77 #elif defined(__amd64__)
78 		*regvalue = regs.r_rsp;
79 #elif defined(__arm__)
80 		*regvalue = regs.r_sp;
81 #elif defined(__i386__)
82 		*regvalue = regs.r_esp;
83 #elif defined(__powerpc__)
84 		*regvalue = regs.fixreg[1];
85 #elif defined(__riscv)
86 		*regvalue = regs.sp;
87 #endif
88 		break;
89 	default:
90 		DPRINTFX("ERROR: no support for reg number %d", reg);
91 		return (-1);
92 	}
93 
94 	return (0);
95 }
96 
97 int
98 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
99 {
100 	struct reg regs;
101 
102 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
103 	    phdl->status == PS_IDLE) {
104 		errno = ENOENT;
105 		return (-1);
106 	}
107 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
108 		return (-1);
109 	switch (reg) {
110 	case REG_PC:
111 #if defined(__aarch64__)
112 		regs.elr = regvalue;
113 #elif defined(__amd64__)
114 		regs.r_rip = regvalue;
115 #elif defined(__arm__)
116 		regs.r_pc = regvalue;
117 #elif defined(__i386__)
118 		regs.r_eip = regvalue;
119 #elif defined(__powerpc__)
120 		regs.pc = regvalue;
121 #elif defined(__riscv)
122 		regs.sepc = regvalue;
123 #endif
124 		break;
125 	case REG_SP:
126 #if defined(__aarch64__)
127 		regs.sp = regvalue;
128 #elif defined(__amd64__)
129 		regs.r_rsp = regvalue;
130 #elif defined(__arm__)
131 		regs.r_sp = regvalue;
132 #elif defined(__i386__)
133 		regs.r_esp = regvalue;
134 #elif defined(__powerpc__)
135 		regs.fixreg[1] = regvalue;
136 #elif defined(__riscv)
137 		regs.sp = regvalue;
138 #endif
139 		break;
140 	default:
141 		DPRINTFX("ERROR: no support for reg number %d", reg);
142 		return (-1);
143 	}
144 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
145 		return (-1);
146 
147 	return (0);
148 }
149