xref: /freebsd/lib/libproc/proc_regs.c (revision 1456f0f9681bbd7fdae7b683553f6c7491508c4e)
1 /*-
2  * Copyright (c) 2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Rui Paulo under sponsorship from the
6  * FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
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(__mips__)
67 		*regvalue = regs.r_regs[PC];
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(__mips__)
84 		*regvalue = regs.r_regs[SP];
85 #elif defined(__powerpc__)
86 		*regvalue = regs.fixreg[1];
87 #elif defined(__riscv__)
88 		*regvalue = regs.sp;
89 #endif
90 		break;
91 	default:
92 		DPRINTFX("ERROR: no support for reg number %d", reg);
93 		return (-1);
94 	}
95 
96 	return (0);
97 }
98 
99 int
100 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
101 {
102 	struct reg regs;
103 
104 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
105 	    phdl->status == PS_IDLE) {
106 		errno = ENOENT;
107 		return (-1);
108 	}
109 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
110 		return (-1);
111 	switch (reg) {
112 	case REG_PC:
113 #if defined(__aarch64__)
114 		regs.elr = regvalue;
115 #elif defined(__amd64__)
116 		regs.r_rip = regvalue;
117 #elif defined(__arm__)
118 		regs.r_pc = regvalue;
119 #elif defined(__i386__)
120 		regs.r_eip = regvalue;
121 #elif defined(__mips__)
122 		regs.r_regs[PC] = regvalue;
123 #elif defined(__powerpc__)
124 		regs.pc = regvalue;
125 #elif defined(__riscv__)
126 		regs.sepc = regvalue;
127 #endif
128 		break;
129 	case REG_SP:
130 #if defined(__aarch64__)
131 		regs.sp = regvalue;
132 #elif defined(__amd64__)
133 		regs.r_rsp = regvalue;
134 #elif defined(__arm__)
135 		regs.r_sp = regvalue;
136 #elif defined(__i386__)
137 		regs.r_esp = regvalue;
138 #elif defined(__mips__)
139 		regs.r_regs[PC] = regvalue;
140 #elif defined(__powerpc__)
141 		regs.fixreg[1] = regvalue;
142 #elif defined(__riscv__)
143 		regs.sp = regvalue;
144 #endif
145 		break;
146 	default:
147 		DPRINTFX("ERROR: no support for reg number %d", reg);
148 		return (-1);
149 	}
150 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
151 		return (-1);
152 
153 	return (0);
154 }
155