1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
/*
* This file is part of the ZFS Event Daemon (ZED)
* for ZFS on Linux (ZoL) <http://zfsonlinux.org/>.
* Developed at Lawrence Livermore National Laboratory (LLNL-CODE-403049).
* Copyright (C) 2013-2014 Lawrence Livermore National Security, LLC.
* Refer to the ZoL git commit log for authoritative copyright attribution.
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License Version 1.0 (CDDL-1.0).
* You can obtain a copy of the license from the top-level file
* "OPENSOLARIS.LICENSE" or at <http://opensource.org/licenses/CDDL-1.0>.
* You may not use this file except in compliance with the license.
*/
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
#include "zed_file.h"
#include "zed_log.h"
#include "zed_strings.h"
#define ZEVENT_FILENO 3
/*
* Create an environment string array for passing to execve() using the
* NAME=VALUE strings in container [zsp].
* Return a newly-allocated environment, or NULL on error.
*/
static char **
_zed_exec_create_env(zed_strings_t *zsp)
{
int num_ptrs;
int buflen;
char *buf;
char **pp;
char *p;
const char *q;
int i;
int len;
num_ptrs = zed_strings_count(zsp) + 1;
buflen = num_ptrs * sizeof (char *);
for (q = zed_strings_first(zsp); q; q = zed_strings_next(zsp))
buflen += strlen(q) + 1;
buf = calloc(1, buflen);
if (!buf)
return (NULL);
pp = (char **) buf;
p = buf + (num_ptrs * sizeof (char *));
i = 0;
for (q = zed_strings_first(zsp); q; q = zed_strings_next(zsp)) {
pp[i] = p;
len = strlen(q) + 1;
memcpy(p, q, len);
p += len;
i++;
}
pp[i] = NULL;
assert(buf + buflen == p);
return ((char **) buf);
}
/*
* Fork a child process to handle event [eid]. The program [prog]
* in directory [dir] is executed with the envionment [env].
*
* The file descriptor [zfd] is the zevent_fd used to track the
* current cursor location within the zevent nvlist.
*/
static void
_zed_exec_fork_child(uint64_t eid, const char *dir, const char *prog,
char *env[], int zfd)
{
char path[PATH_MAX];
int n;
pid_t pid;
int fd;
pid_t wpid;
int status;
assert(dir != NULL);
assert(prog != NULL);
assert(env != NULL);
assert(zfd >= 0);
n = snprintf(path, sizeof (path), "%s/%s", dir, prog);
if ((n < 0) || (n >= sizeof (path))) {
zed_log_msg(LOG_WARNING,
"Failed to fork \"%s\" for eid=%llu: %s",
prog, eid, strerror(ENAMETOOLONG));
return;
}
pid = fork();
if (pid < 0) {
zed_log_msg(LOG_WARNING,
"Failed to fork \"%s\" for eid=%llu: %s",
prog, eid, strerror(errno));
return;
} else if (pid == 0) {
(void) umask(022);
if ((fd = open("/dev/null", O_RDWR)) != -1) {
(void) dup2(fd, STDIN_FILENO);
(void) dup2(fd, STDOUT_FILENO);
(void) dup2(fd, STDERR_FILENO);
}
(void) dup2(zfd, ZEVENT_FILENO);
zed_file_close_from(ZEVENT_FILENO + 1);
execle(path, prog, NULL, env);
_exit(127);
} else {
zed_log_msg(LOG_INFO, "Invoking \"%s\" eid=%llu pid=%d",
prog, eid, pid);
/* FIXME: Timeout rogue child processes with sigalarm? */
restart:
wpid = waitpid(pid, &status, 0);
if (wpid == (pid_t) -1) {
if (errno == EINTR)
goto restart;
zed_log_msg(LOG_WARNING,
"Failed to wait for \"%s\" eid=%llu pid=%d",
prog, eid, pid);
} else if (WIFEXITED(status)) {
zed_log_msg(LOG_INFO,
"Finished \"%s\" eid=%llu pid=%d exit=%d",
prog, eid, pid, WEXITSTATUS(status));
} else if (WIFSIGNALED(status)) {
zed_log_msg(LOG_INFO,
"Finished \"%s\" eid=%llu pid=%d sig=%d/%s",
prog, eid, pid, WTERMSIG(status),
strsignal(WTERMSIG(status)));
} else {
zed_log_msg(LOG_INFO,
"Finished \"%s\" eid=%llu pid=%d status=0x%X",
prog, eid, (unsigned int) status);
}
}
}
/*
* Process the event [eid] by synchronously invoking all zedlets with a
* matching class prefix.
*
* Each executable in [zedlets] from the directory [dir] is matched against
* the event's [class], [subclass], and the "all" class (which matches
* all events). Every zedlet with a matching class prefix is invoked.
* The NAME=VALUE strings in [envs] will be passed to the zedlet as
* environment variables.
*
* The file descriptor [zfd] is the zevent_fd used to track the
* current cursor location within the zevent nvlist.
*
* Return 0 on success, -1 on error.
*/
int
zed_exec_process(uint64_t eid, const char *class, const char *subclass,
const char *dir, zed_strings_t *zedlets, zed_strings_t *envs, int zfd)
{
const char *class_strings[4];
const char *allclass = "all";
const char **csp;
const char *z;
char **e;
int n;
if (!dir || !zedlets || !envs || zfd < 0)
return (-1);
csp = class_strings;
if (class)
*csp++ = class;
if (subclass)
*csp++ = subclass;
if (allclass)
*csp++ = allclass;
*csp = NULL;
e = _zed_exec_create_env(envs);
for (z = zed_strings_first(zedlets); z; z = zed_strings_next(zedlets)) {
for (csp = class_strings; *csp; csp++) {
n = strlen(*csp);
if ((strncmp(z, *csp, n) == 0) && !isalpha(z[n]))
_zed_exec_fork_child(eid, dir, z, e, zfd);
}
}
free(e);
return (0);
}
|
