xref: /freebsd/lib/libproc/proc_util.c (revision 32734eb14c5cc3aa4ad576ba746830c73fb8eb54)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2010 The FreeBSD Foundation
5  * Copyright (c) 2008 John Birrell (jb@freebsd.org)
6  * All rights reserved.
7  *
8  * Portions of this software were developed by Rui Paulo under sponsorship
9  * from the FreeBSD Foundation.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/types.h>
37 #include <sys/ptrace.h>
38 #include <sys/wait.h>
39 
40 #include <err.h>
41 #include <errno.h>
42 #include <signal.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #include "_libproc.h"
47 
48 int
49 proc_clearflags(struct proc_handle *phdl, int mask)
50 {
51 
52 	if (phdl == NULL)
53 		return (EINVAL);
54 
55 	phdl->flags &= ~mask;
56 
57 	return (0);
58 }
59 
60 /*
61  * NB: we return -1 as the Solaris libproc Psetrun() function.
62  */
63 int
64 proc_continue(struct proc_handle *phdl)
65 {
66 	int pending;
67 
68 	if (phdl == NULL)
69 		return (-1);
70 
71 	if (phdl->status == PS_STOP && WSTOPSIG(phdl->wstat) != SIGTRAP)
72 		pending = WSTOPSIG(phdl->wstat);
73 	else
74 		pending = 0;
75 	if (ptrace(PT_CONTINUE, proc_getpid(phdl), (caddr_t)(uintptr_t)1,
76 	    pending) != 0)
77 		return (-1);
78 
79 	phdl->status = PS_RUN;
80 
81 	return (0);
82 }
83 
84 int
85 proc_detach(struct proc_handle *phdl, int reason)
86 {
87 	int status;
88 	int request;
89 	pid_t pid;
90 
91 	if (phdl == NULL)
92 		return (EINVAL);
93 	if (reason == PRELEASE_HANG)
94 		return (EINVAL);
95 	if ((phdl->flags & PATTACH_RDONLY) != 0)
96 		goto free;
97 	request = (reason == PRELEASE_KILL) ? PT_KILL : PT_DETACH;
98 	pid = proc_getpid(phdl);
99 	if (ptrace(request, pid, 0, 0) != 0 && errno == EBUSY) {
100 		kill(pid, SIGSTOP);
101 		waitpid(pid, &status, WUNTRACED);
102 		ptrace(request, pid, 0, 0);
103 		kill(pid, SIGCONT);
104 	}
105 free:
106 	proc_free(phdl);
107 	return (0);
108 }
109 
110 int
111 proc_getflags(struct proc_handle *phdl)
112 {
113 
114 	if (phdl == NULL)
115 		return (-1);
116 
117 	return (phdl->flags);
118 }
119 
120 int
121 proc_setflags(struct proc_handle *phdl, int mask)
122 {
123 
124 	if (phdl == NULL)
125 		return (EINVAL);
126 
127 	phdl->flags |= mask;
128 
129 	return (0);
130 }
131 
132 int
133 proc_state(struct proc_handle *phdl)
134 {
135 
136 	if (phdl == NULL)
137 		return (-1);
138 
139 	return (phdl->status);
140 }
141 
142 int
143 proc_getmodel(struct proc_handle *phdl)
144 {
145 
146 	if (phdl == NULL)
147 		return (-1);
148 
149 	return (phdl->model);
150 }
151 
152 int
153 proc_wstatus(struct proc_handle *phdl)
154 {
155 	int status;
156 
157 	if (phdl == NULL)
158 		return (-1);
159 	if (waitpid(proc_getpid(phdl), &status, WUNTRACED) < 0) {
160 		if (errno != EINTR)
161 			DPRINTF("waitpid");
162 		return (-1);
163 	}
164 	if (WIFSTOPPED(status))
165 		phdl->status = PS_STOP;
166 	if (WIFEXITED(status) || WIFSIGNALED(status))
167 		phdl->status = PS_UNDEAD;
168 	phdl->wstat = status;
169 
170 	return (phdl->status);
171 }
172 
173 int
174 proc_getwstat(struct proc_handle *phdl)
175 {
176 
177 	if (phdl == NULL)
178 		return (-1);
179 
180 	return (phdl->wstat);
181 }
182 
183 char *
184 proc_signame(int sig, char *name, size_t namesz)
185 {
186 
187 	strlcpy(name, strsignal(sig), namesz);
188 
189 	return (name);
190 }
191 
192 int
193 proc_read(struct proc_handle *phdl, void *buf, size_t size, size_t addr)
194 {
195 	struct ptrace_io_desc piod;
196 
197 	if (phdl == NULL)
198 		return (-1);
199 	piod.piod_op = PIOD_READ_D;
200 	piod.piod_len = size;
201 	piod.piod_addr = (void *)buf;
202 	piod.piod_offs = (void *)addr;
203 
204 	if (ptrace(PT_IO, proc_getpid(phdl), (caddr_t)&piod, 0) < 0)
205 		return (-1);
206 	return (piod.piod_len);
207 }
208 
209 const lwpstatus_t *
210 proc_getlwpstatus(struct proc_handle *phdl)
211 {
212 	struct ptrace_lwpinfo lwpinfo;
213 	lwpstatus_t *psp = &phdl->lwps;
214 	siginfo_t *siginfo;
215 
216 	if (phdl == NULL)
217 		return (NULL);
218 	if (ptrace(PT_LWPINFO, proc_getpid(phdl), (caddr_t)&lwpinfo,
219 	    sizeof(lwpinfo)) < 0)
220 		return (NULL);
221 	siginfo = &lwpinfo.pl_siginfo;
222 	if (lwpinfo.pl_event == PL_EVENT_SIGNAL &&
223 	    (lwpinfo.pl_flags & PL_FLAG_SI) != 0) {
224 		if (siginfo->si_signo == SIGTRAP &&
225 		    (siginfo->si_code == TRAP_BRKPT ||
226 		    siginfo->si_code == TRAP_TRACE)) {
227 			psp->pr_why = PR_FAULTED;
228 			psp->pr_what = FLTBPT;
229 		} else {
230 			psp->pr_why = PR_SIGNALLED;
231 			psp->pr_what = siginfo->si_signo;
232 		}
233 	} else if (lwpinfo.pl_flags & PL_FLAG_SCE) {
234 		psp->pr_why = PR_SYSENTRY;
235 	} else if (lwpinfo.pl_flags & PL_FLAG_SCX) {
236 		psp->pr_why = PR_SYSEXIT;
237 	}
238 
239 	return (psp);
240 }
241