xref: /freebsd/lib/libproc/proc_util.c (revision 63a938566d524836885917d95bd491aa4400b181)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 	pid_t pid;
89 
90 	if (phdl == NULL)
91 		return (EINVAL);
92 	if (reason == PRELEASE_HANG)
93 		return (EINVAL);
94 	if (reason == PRELEASE_KILL) {
95 		kill(proc_getpid(phdl), SIGKILL);
96 		goto free;
97 	}
98 	if ((phdl->flags & PATTACH_RDONLY) != 0)
99 		goto free;
100 	pid = proc_getpid(phdl);
101 	if (ptrace(PT_DETACH, pid, 0, 0) != 0 && errno == ESRCH)
102 		goto free;
103 	if (errno == EBUSY) {
104 		kill(pid, SIGSTOP);
105 		waitpid(pid, &status, WUNTRACED);
106 		ptrace(PT_DETACH, pid, 0, 0);
107 		kill(pid, SIGCONT);
108 	}
109 free:
110 	proc_free(phdl);
111 	return (0);
112 }
113 
114 int
115 proc_getflags(struct proc_handle *phdl)
116 {
117 
118 	if (phdl == NULL)
119 		return (-1);
120 
121 	return (phdl->flags);
122 }
123 
124 int
125 proc_setflags(struct proc_handle *phdl, int mask)
126 {
127 
128 	if (phdl == NULL)
129 		return (EINVAL);
130 
131 	phdl->flags |= mask;
132 
133 	return (0);
134 }
135 
136 int
137 proc_state(struct proc_handle *phdl)
138 {
139 
140 	if (phdl == NULL)
141 		return (-1);
142 
143 	return (phdl->status);
144 }
145 
146 int
147 proc_getmodel(struct proc_handle *phdl)
148 {
149 
150 	if (phdl == NULL)
151 		return (-1);
152 
153 	return (phdl->model);
154 }
155 
156 int
157 proc_wstatus(struct proc_handle *phdl)
158 {
159 	int status;
160 
161 	if (phdl == NULL)
162 		return (-1);
163 	if (waitpid(proc_getpid(phdl), &status, WUNTRACED) < 0) {
164 		if (errno != EINTR)
165 			DPRINTF("waitpid");
166 		return (-1);
167 	}
168 	if (WIFSTOPPED(status))
169 		phdl->status = PS_STOP;
170 	if (WIFEXITED(status) || WIFSIGNALED(status))
171 		phdl->status = PS_UNDEAD;
172 	phdl->wstat = status;
173 
174 	return (phdl->status);
175 }
176 
177 int
178 proc_getwstat(struct proc_handle *phdl)
179 {
180 
181 	if (phdl == NULL)
182 		return (-1);
183 
184 	return (phdl->wstat);
185 }
186 
187 char *
188 proc_signame(int sig, char *name, size_t namesz)
189 {
190 
191 	strlcpy(name, strsignal(sig), namesz);
192 
193 	return (name);
194 }
195 
196 int
197 proc_read(struct proc_handle *phdl, void *buf, size_t size, size_t addr)
198 {
199 	struct ptrace_io_desc piod;
200 
201 	if (phdl == NULL)
202 		return (-1);
203 	piod.piod_op = PIOD_READ_D;
204 	piod.piod_len = size;
205 	piod.piod_addr = (void *)buf;
206 	piod.piod_offs = (void *)addr;
207 
208 	if (ptrace(PT_IO, proc_getpid(phdl), (caddr_t)&piod, 0) < 0)
209 		return (-1);
210 	return (piod.piod_len);
211 }
212 
213 const lwpstatus_t *
214 proc_getlwpstatus(struct proc_handle *phdl)
215 {
216 	struct ptrace_lwpinfo lwpinfo;
217 	lwpstatus_t *psp = &phdl->lwps;
218 	siginfo_t *siginfo;
219 
220 	if (phdl == NULL)
221 		return (NULL);
222 	if (ptrace(PT_LWPINFO, proc_getpid(phdl), (caddr_t)&lwpinfo,
223 	    sizeof(lwpinfo)) < 0)
224 		return (NULL);
225 	siginfo = &lwpinfo.pl_siginfo;
226 	if (lwpinfo.pl_event == PL_EVENT_SIGNAL &&
227 	    (lwpinfo.pl_flags & PL_FLAG_SI) != 0) {
228 		if (siginfo->si_signo == SIGTRAP &&
229 		    (siginfo->si_code == TRAP_BRKPT ||
230 		    siginfo->si_code == TRAP_TRACE)) {
231 			psp->pr_why = PR_FAULTED;
232 			psp->pr_what = FLTBPT;
233 		} else {
234 			psp->pr_why = PR_SIGNALLED;
235 			psp->pr_what = siginfo->si_signo;
236 		}
237 	} else if (lwpinfo.pl_flags & PL_FLAG_SCE) {
238 		psp->pr_why = PR_SYSENTRY;
239 	} else if (lwpinfo.pl_flags & PL_FLAG_SCX) {
240 		psp->pr_why = PR_SYSEXIT;
241 	}
242 
243 	return (psp);
244 }
245