xref: /freebsd/lib/libproc/proc_util.c (revision b2db760808f74bb53c232900091c9da801ebbfcc)
1 /*-
2  * Copyright (c) 2010 The FreeBSD Foundation
3  * Copyright (c) 2008 John Birrell (jb@freebsd.org)
4  * All rights reserved.
5  *
6  * Portions of this software were developed by Rui Paulo under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #include <sys/types.h>
34 #include <sys/ptrace.h>
35 #include <sys/wait.h>
36 #include <err.h>
37 #include <errno.h>
38 #include <unistd.h>
39 #include <stdio.h>
40 #include <signal.h>
41 #include <string.h>
42 #include "_libproc.h"
43 
44 int
45 proc_clearflags(struct proc_handle *phdl, int mask)
46 {
47 
48 	if (phdl == NULL)
49 		return (EINVAL);
50 
51 	phdl->flags &= ~mask;
52 
53 	return (0);
54 }
55 
56 /*
57  * NB: we return -1 as the Solaris libproc Psetrun() function.
58  */
59 int
60 proc_continue(struct proc_handle *phdl)
61 {
62 
63 	if (phdl == NULL)
64 		return (-1);
65 
66 	if (ptrace(PT_CONTINUE, phdl->pid, (caddr_t)(uintptr_t) 1, 0) != 0)
67 		return (-1);
68 
69 	phdl->status = PS_RUN;
70 
71 	return (0);
72 }
73 
74 int
75 proc_detach(struct proc_handle *phdl, int reason)
76 {
77 	int status;
78 
79 	if (phdl == NULL)
80 		return (EINVAL);
81 	if (reason == PRELEASE_KILL) {
82 		kill(phdl->pid, SIGKILL);
83 		return (0);
84 	}
85 	if (ptrace(PT_DETACH, phdl->pid, 0, 0) != 0 && errno == ESRCH)
86 		return (0);
87 	if (errno == EBUSY) {
88 		kill(phdl->pid, SIGSTOP);
89 		waitpid(phdl->pid, &status, WUNTRACED);
90 		ptrace(PT_DETACH, phdl->pid, 0, 0);
91 		kill(phdl->pid, SIGCONT);
92 		return (0);
93 	}
94 
95 	return (0);
96 }
97 
98 int
99 proc_getflags(struct proc_handle *phdl)
100 {
101 
102 	if (phdl == NULL)
103 		return (-1);
104 
105 	return(phdl->flags);
106 }
107 
108 int
109 proc_setflags(struct proc_handle *phdl, int mask)
110 {
111 
112 	if (phdl == NULL)
113 		return (EINVAL);
114 
115 	phdl->flags |= mask;
116 
117 	return (0);
118 }
119 
120 int
121 proc_state(struct proc_handle *phdl)
122 {
123 
124 	if (phdl == NULL)
125 		return (-1);
126 
127 	return (phdl->status);
128 }
129 
130 pid_t
131 proc_getpid(struct proc_handle *phdl)
132 {
133 
134 	if (phdl == NULL)
135 		return (-1);
136 
137 	return (phdl->pid);
138 }
139 
140 int
141 proc_wstatus(struct proc_handle *phdl)
142 {
143 	int status;
144 
145 	if (phdl == NULL)
146 		return (-1);
147 	if (waitpid(phdl->pid, &status, WUNTRACED) < 0) {
148 		warn("waitpid");
149 		return (-1);
150 	}
151 	if (WIFSTOPPED(status))
152 		phdl->status = PS_STOP;
153 	if (WIFEXITED(status) || WIFSIGNALED(status))
154 		phdl->status = PS_UNDEAD;
155 	phdl->wstat = status;
156 
157 	return (phdl->status);
158 }
159 
160 int
161 proc_getwstat(struct proc_handle *phdl)
162 {
163 
164 	if (phdl == NULL)
165 		return (-1);
166 
167 	return (phdl->wstat);
168 }
169 
170 char *
171 proc_signame(int sig, char *name, size_t namesz)
172 {
173 
174 	strlcpy(name, strsignal(sig), namesz);
175 
176 	return (name);
177 }
178 
179 int
180 proc_read(struct proc_handle *phdl, void *buf, size_t size, size_t addr)
181 {
182 	struct ptrace_io_desc piod;
183 
184 	if (phdl == NULL)
185 		return (-1);
186 	piod.piod_op = PIOD_READ_D;
187 	piod.piod_len = size;
188 	piod.piod_addr = (void *)buf;
189 	piod.piod_offs = (void *)addr;
190 
191 	if (ptrace(PT_IO, phdl->pid, (caddr_t)&piod, 0) < 0)
192 		return (-1);
193 	return (piod.piod_len);
194 }
195 
196 const lwpstatus_t *
197 proc_getlwpstatus(struct proc_handle *phdl)
198 {
199 	struct ptrace_lwpinfo lwpinfo;
200 	lwpstatus_t *psp = &phdl->lwps;
201 	siginfo_t *siginfo;
202 
203 	if (phdl == NULL)
204 		return (NULL);
205 	if (ptrace(PT_LWPINFO, phdl->pid, (caddr_t)&lwpinfo,
206 	    sizeof(lwpinfo)) < 0)
207 		return (NULL);
208 	siginfo = &lwpinfo.pl_siginfo;
209 	if (lwpinfo.pl_event == PL_EVENT_SIGNAL &&
210 	    (lwpinfo.pl_flags & PL_FLAG_SI) &&
211 	    siginfo->si_signo == SIGTRAP &&
212 	    (siginfo->si_code == TRAP_BRKPT ||
213 	    siginfo->si_code == TRAP_TRACE)) {
214 		psp->pr_why = PR_FAULTED;
215 		psp->pr_what = FLTBPT;
216 	} else if (lwpinfo.pl_flags & PL_FLAG_SCE) {
217 		psp->pr_why = PR_SYSENTRY;
218 	} else if (lwpinfo.pl_flags & PL_FLAG_SCX) {
219 		psp->pr_why = PR_SYSEXIT;
220 	}
221 
222 	return (psp);
223 }
224