xref: /freebsd/lib/libproc/proc_regs.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #include <sys/types.h>
34 #include <sys/ptrace.h>
35 
36 #include <err.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <errno.h>
40 
41 #include "_libproc.h"
42 
43 int
44 proc_regget(struct proc_handle *phdl, proc_reg_t reg, unsigned long *regvalue)
45 {
46 	struct reg regs;
47 
48 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
49 	    phdl->status == PS_IDLE) {
50 		errno = ENOENT;
51 		return (-1);
52 	}
53 	memset(&regs, 0, sizeof(regs));
54 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
55 		return (-1);
56 	switch (reg) {
57 	case REG_PC:
58 #if defined(__aarch64__)
59 		*regvalue = regs.elr;
60 #elif defined(__amd64__)
61 		*regvalue = regs.r_rip;
62 #elif defined(__arm__)
63 		*regvalue = regs.r_pc;
64 #elif defined(__i386__)
65 		*regvalue = regs.r_eip;
66 #elif defined(__powerpc__)
67 		*regvalue = regs.pc;
68 #elif defined(__riscv)
69 		*regvalue = regs.sepc;
70 #endif
71 		break;
72 	case REG_SP:
73 #if defined(__aarch64__)
74 		*regvalue = regs.sp;
75 #elif defined(__amd64__)
76 		*regvalue = regs.r_rsp;
77 #elif defined(__arm__)
78 		*regvalue = regs.r_sp;
79 #elif defined(__i386__)
80 		*regvalue = regs.r_esp;
81 #elif defined(__powerpc__)
82 		*regvalue = regs.fixreg[1];
83 #elif defined(__riscv)
84 		*regvalue = regs.sp;
85 #endif
86 		break;
87 	default:
88 		DPRINTFX("ERROR: no support for reg number %d", reg);
89 		return (-1);
90 	}
91 
92 	return (0);
93 }
94 
95 int
96 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
97 {
98 	struct reg regs;
99 
100 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
101 	    phdl->status == PS_IDLE) {
102 		errno = ENOENT;
103 		return (-1);
104 	}
105 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
106 		return (-1);
107 	switch (reg) {
108 	case REG_PC:
109 #if defined(__aarch64__)
110 		regs.elr = regvalue;
111 #elif defined(__amd64__)
112 		regs.r_rip = regvalue;
113 #elif defined(__arm__)
114 		regs.r_pc = regvalue;
115 #elif defined(__i386__)
116 		regs.r_eip = regvalue;
117 #elif defined(__powerpc__)
118 		regs.pc = regvalue;
119 #elif defined(__riscv)
120 		regs.sepc = regvalue;
121 #endif
122 		break;
123 	case REG_SP:
124 #if defined(__aarch64__)
125 		regs.sp = regvalue;
126 #elif defined(__amd64__)
127 		regs.r_rsp = regvalue;
128 #elif defined(__arm__)
129 		regs.r_sp = regvalue;
130 #elif defined(__i386__)
131 		regs.r_esp = regvalue;
132 #elif defined(__powerpc__)
133 		regs.fixreg[1] = regvalue;
134 #elif defined(__riscv)
135 		regs.sp = regvalue;
136 #endif
137 		break;
138 	default:
139 		DPRINTFX("ERROR: no support for reg number %d", reg);
140 		return (-1);
141 	}
142 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
143 		return (-1);
144 
145 	return (0);
146 }
147