xref: /illumos-gate/usr/src/cmd/acctadm/utils.c (revision 9b4e3ac25d882519cad3fc11f0c53b07f4e60536)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <assert.h>
27 #include <sys/types.h>
28 #include <sys/acctctl.h>
29 #include <sys/param.h>
30 #include <sys/stat.h>
31 #include <libintl.h>
32 #include <string.h>
33 #include <stdlib.h>
34 #include <stdarg.h>
35 #include <stdio.h>
36 #include <strings.h>
37 #include <unistd.h>
38 #include <errno.h>
39 #include <exacct.h>
40 #include <fcntl.h>
41 #include <priv.h>
42 
43 #include "utils.h"
44 
45 static char PNAME_FMT[] = "%s: ";
46 static char ERRNO_FMT[] = ": %s\n";
47 
48 static char *pname;
49 
50 /*PRINTFLIKE1*/
51 void
52 warn(const char *format, ...)
53 {
54 	int err = errno;
55 	va_list alist;
56 	if (pname != NULL)
57 		(void) fprintf(stderr, gettext(PNAME_FMT), pname);
58 	va_start(alist, format);
59 	(void) vfprintf(stderr, format, alist);
60 	va_end(alist);
61 	if (strchr(format, '\n') == NULL)
62 		(void) fprintf(stderr, gettext(ERRNO_FMT), strerror(err));
63 }
64 
65 /*PRINTFLIKE1*/
66 void
67 die(char *format, ...)
68 {
69 	int err = errno;
70 	va_list alist;
71 
72 	if (pname != NULL)
73 		(void) fprintf(stderr, gettext(PNAME_FMT), pname);
74 	va_start(alist, format);
75 	(void) vfprintf(stderr, format, alist);
76 	va_end(alist);
77 	if (strchr(format, '\n') == NULL)
78 		(void) fprintf(stderr, gettext(ERRNO_FMT), strerror(err));
79 	exit(E_ERROR);
80 }
81 
82 char *
83 setprogname(char *arg0)
84 {
85 	char *p = strrchr(arg0, '/');
86 
87 	if (p == NULL)
88 		p = arg0;
89 	else
90 		p++;
91 	pname = p;
92 	return (pname);
93 }
94 
95 /*
96  * Return the localized name of an accounting type.
97  */
98 const char *
99 ac_type_name(int type)
100 {
101 	switch (type) {
102 	case AC_PROC:
103 		return (gettext("process"));
104 	case AC_FLOW:
105 		return (gettext("flow"));
106 	case AC_TASK:
107 		return (gettext("task"));
108 	case AC_NET:
109 		return (gettext("net"));
110 	default:
111 		die(gettext("invalid type %d\n"), type);
112 	}
113 	/* NOTREACHED */
114 	return (NULL);
115 }
116 
117 /*
118  * Open an accounting file.  The filename specified must be an absolute
119  * pathname and the existing contents of the file (if any) must be of the
120  * requested type.  Needs euid 0 to open the root-owned accounting file.
121  * file_dac_write is required to create a new file in a directory not owned
122  * by root (/var/adm/exacct is owned by 'adm').  Assumes sys_acct privilege is
123  * already asserted by caller.
124  */
125 int
126 open_exacct_file(const char *file, int type)
127 {
128 	int rc;
129 	int err;
130 
131 	if (file[0] != '/') {
132 		warn(gettext("%s is not an absolute pathname\n"), file);
133 		return (-1);
134 	}
135 	if (!verify_exacct_file(file, type)) {
136 		warn(gettext("%s is not a %s accounting file\n"), file,
137 		    ac_type_name(type));
138 		return (-1);
139 	}
140 	if (seteuid(0) == -1 || setegid(0) == -1) {
141 		warn(gettext("seteuid()/setegid() failed"));
142 		return (-1);
143 	}
144 	assert(priv_ineffect(PRIV_SYS_ACCT));
145 	(void) priv_set(PRIV_ON, PRIV_EFFECTIVE, PRIV_FILE_DAC_WRITE, NULL);
146 	rc = acctctl(type | AC_FILE_SET, (void *) file, strlen(file) + 1);
147 	if (rc == -1 && (err = errno) == EBUSY) {
148 		char name[MAXPATHLEN];
149 		struct stat cur;
150 		struct stat new;
151 
152 		/*
153 		 * The file is already open as an accounting file somewhere.
154 		 * If the file we're trying to open is the same as we have
155 		 * currently open then we're ok.
156 		 */
157 		if (acctctl(type | AC_FILE_GET, name, sizeof (name)) == 0 &&
158 		    stat(file, &new) != -1 && stat(name, &cur) != -1 &&
159 		    new.st_dev == cur.st_dev && new.st_ino == cur.st_ino)
160 			rc = 0;
161 	}
162 
163 	/*
164 	 * euid 0, egid 0 and the file_dac_write privilege are no longer
165 	 * required; give them up permanently.
166 	 */
167 	(void) priv_set(PRIV_OFF, PRIV_PERMITTED, PRIV_FILE_DAC_WRITE, NULL);
168 	if (setreuid(getuid(), getuid()) == -1 ||
169 	    setregid(getgid(), getgid()) == -1)
170 		die(gettext("setreuid()/setregid() failed"));
171 	if (rc == 0)
172 		return (0);
173 
174 	warn(gettext("cannot open %s accounting file %s: %s\n"),
175 	    ac_type_name(type), file, strerror(err));
176 	return (-1);
177 }
178 
179 /*
180  * Verify that the file contents (if any) are extended accounting records
181  * of the desired type.
182  */
183 boolean_t
184 verify_exacct_file(const char *file, int type)
185 {
186 	ea_file_t ef;
187 	ea_object_t eo;
188 	struct stat st;
189 	int err;
190 
191 	if (stat(file, &st) != -1 && st.st_size != 0) {
192 		if (seteuid(0) == -1)
193 			return (B_FALSE);
194 		err = ea_open(&ef, file, "SunOS", EO_TAIL, O_RDONLY, 0);
195 		if (seteuid(getuid()) == 1)
196 			die(gettext("seteuid() failed"));
197 		if (err == -1)
198 			return (B_FALSE);
199 
200 		bzero(&eo, sizeof (eo));
201 		if (ea_previous_object(&ef, &eo) == EO_ERROR) {
202 			/*
203 			 * EXR_EOF indicates there are no non-header objects
204 			 * in the file.  It can't be determined that this
205 			 * file is or is not the proper type of extended
206 			 * accounting file, which isn't necessarily an error.
207 			 * Since it is a proper (albeit empty) extended
208 			 * accounting file, it matches any desired type.
209 			 *
210 			 * if ea_previous_object() failed for any other reason
211 			 * than EXR_EOF, the file must be corrupt.
212 			 */
213 			if (ea_error() != EXR_EOF) {
214 				(void) ea_close(&ef);
215 				return (B_FALSE);
216 			}
217 		} else {
218 			/*
219 			 * A non-header object exists.  Insist that it be
220 			 * either a process, task, flow  or net accounting
221 			 * record, the same type as is desired.
222 			 * xxx-venu:check 101 merge for EXD_GROUP_NET_*
223 			 */
224 			uint_t c = eo.eo_catalog & EXD_DATA_MASK;
225 
226 			if (eo.eo_type != EO_GROUP ||
227 			    (eo.eo_catalog & EXC_CATALOG_MASK) != EXC_NONE ||
228 			    (!(c == EXD_GROUP_PROC && type == AC_PROC ||
229 			    c == EXD_GROUP_TASK && type == AC_TASK ||
230 			    c == EXD_GROUP_FLOW && type == AC_FLOW ||
231 			    (c == EXD_GROUP_NET_LINK_DESC ||
232 			    c == EXD_GROUP_NET_FLOW_DESC ||
233 			    c == EXD_GROUP_NET_LINK_STATS ||
234 			    c == EXD_GROUP_NET_FLOW_STATS) &&
235 			    type == AC_NET))) {
236 				(void) ea_close(&ef);
237 				return (B_FALSE);
238 			}
239 		}
240 		(void) ea_close(&ef);
241 	}
242 	return (B_TRUE);
243 }
244