xref: /freebsd/lib/libproc/proc_regs.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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/types.h>
33 #include <sys/ptrace.h>
34 
35 #include <err.h>
36 #include <stdio.h>
37 #include <string.h>
38 #include <errno.h>
39 
40 #include "_libproc.h"
41 
42 int
43 proc_regget(struct proc_handle *phdl, proc_reg_t reg, unsigned long *regvalue)
44 {
45 	struct reg regs;
46 
47 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
48 	    phdl->status == PS_IDLE) {
49 		errno = ENOENT;
50 		return (-1);
51 	}
52 	memset(&regs, 0, sizeof(regs));
53 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
54 		return (-1);
55 	switch (reg) {
56 	case REG_PC:
57 #if defined(__aarch64__)
58 		*regvalue = regs.elr;
59 #elif defined(__amd64__)
60 		*regvalue = regs.r_rip;
61 #elif defined(__arm__)
62 		*regvalue = regs.r_pc;
63 #elif defined(__i386__)
64 		*regvalue = regs.r_eip;
65 #elif defined(__powerpc__)
66 		*regvalue = regs.pc;
67 #elif defined(__riscv)
68 		*regvalue = regs.sepc;
69 #endif
70 		break;
71 	case REG_SP:
72 #if defined(__aarch64__)
73 		*regvalue = regs.sp;
74 #elif defined(__amd64__)
75 		*regvalue = regs.r_rsp;
76 #elif defined(__arm__)
77 		*regvalue = regs.r_sp;
78 #elif defined(__i386__)
79 		*regvalue = regs.r_esp;
80 #elif defined(__powerpc__)
81 		*regvalue = regs.fixreg[1];
82 #elif defined(__riscv)
83 		*regvalue = regs.sp;
84 #endif
85 		break;
86 	default:
87 		DPRINTFX("ERROR: no support for reg number %d", reg);
88 		return (-1);
89 	}
90 
91 	return (0);
92 }
93 
94 int
95 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
96 {
97 	struct reg regs;
98 
99 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
100 	    phdl->status == PS_IDLE) {
101 		errno = ENOENT;
102 		return (-1);
103 	}
104 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
105 		return (-1);
106 	switch (reg) {
107 	case REG_PC:
108 #if defined(__aarch64__)
109 		regs.elr = regvalue;
110 #elif defined(__amd64__)
111 		regs.r_rip = regvalue;
112 #elif defined(__arm__)
113 		regs.r_pc = regvalue;
114 #elif defined(__i386__)
115 		regs.r_eip = regvalue;
116 #elif defined(__powerpc__)
117 		regs.pc = regvalue;
118 #elif defined(__riscv)
119 		regs.sepc = regvalue;
120 #endif
121 		break;
122 	case REG_SP:
123 #if defined(__aarch64__)
124 		regs.sp = regvalue;
125 #elif defined(__amd64__)
126 		regs.r_rsp = regvalue;
127 #elif defined(__arm__)
128 		regs.r_sp = regvalue;
129 #elif defined(__i386__)
130 		regs.r_esp = regvalue;
131 #elif defined(__powerpc__)
132 		regs.fixreg[1] = regvalue;
133 #elif defined(__riscv)
134 		regs.sp = regvalue;
135 #endif
136 		break;
137 	default:
138 		DPRINTFX("ERROR: no support for reg number %d", reg);
139 		return (-1);
140 	}
141 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
142 		return (-1);
143 
144 	return (0);
145 }
146