xref: /illumos-gate/usr/src/cmd/vscan/vscand/vs_svc.c (revision b6c3f786)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * Implementation of the "scan file" interface
30  */
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <string.h>
36 #include <errno.h>
37 #include <syslog.h>
38 #include <sys/types.h>
39 #include <fcntl.h>
40 #include <bsm/adt.h>
41 #include <bsm/adt_event.h>
42 
43 #include "vs_incl.h"
44 
45 /* local functions */
46 static void vs_svc_vlog(char *, vs_result_t *);
47 static void vs_svc_audit(char *, vs_result_t *);
48 
49 /*
50  * vs_svc_init, vs_svc_fini
51  *
52  * Invoked on daemon load and unload
53  */
54 void
55 vs_svc_init()
56 {
57 }
58 
59 void
60 vs_svc_fini()
61 {
62 }
63 
64 
65 /*
66  * vs_svc_scan_file
67  *
68  * vs_svc_scan_file is responsible for:
69  *  - determining if a scan is required
70  *  - obtaining & releasing a scan engine connection
71  *  - invoking the scan engine interface code to do the scan
72  *  - retrying a failed scan (up to VS_MAX_RETRY times)
73  *  - updating scan statistics
74  *  - logging virus information
75  *
76  *
77  * Returns:
78  *  VS_STATUS_NO_SCAN - scan not reqd, or daemon shutting down
79  *  VS_STATUS_CLEAN - scan success. File clean.
80  *                    new scanstamp returned in scanstamp param.
81  *  VS_STATUS_INFECTED - scan success. File infected.
82  *  VS_STATUS_ERROR - scan failure either in vscand or scan engine.
83  */
84 int
85 vs_svc_scan_file(char *devname, char *fname, vs_attr_t *fattr, int flags,
86     vs_scanstamp_t *scanstamp)
87 {
88 	vs_eng_conn_t conn;
89 	int retries;
90 	vs_result_t result;
91 
92 	/* initialize response scanstamp to current scanstamp value */
93 	(void) strlcpy(*scanstamp, fattr->vsa_scanstamp,
94 	    sizeof (vs_scanstamp_t));
95 
96 
97 	/* No scan if file quarantined */
98 	if (fattr->vsa_quarantined)
99 		return (VS_STATUS_NO_SCAN);
100 
101 	/* No scan if file not modified AND scanstamp is current */
102 	if ((fattr->vsa_modified == 0) &&
103 	    vs_eng_scanstamp_current(fattr->vsa_scanstamp)) {
104 		return (VS_STATUS_NO_SCAN);
105 	}
106 
107 	(void) memset(&result, 0, sizeof (vs_result_t));
108 	result.vsr_rc = VS_RESULT_UNDEFINED;
109 
110 	for (retries = 0; retries <= VS_MAX_RETRY; retries++) {
111 		/* identify available engine connection */
112 		if (vs_eng_get(&conn, retries) != 0) {
113 			result.vsr_rc = VS_RESULT_ERROR;
114 			continue;
115 		}
116 
117 		/* connect to engine and scan file */
118 		if (vs_eng_connect(&conn) != 0) {
119 			result.vsr_rc = VS_RESULT_SE_ERROR;
120 		} else {
121 			if (vscand_get_state() == VS_STATE_SHUTDOWN) {
122 				vs_eng_release(&conn);
123 				return (VS_STATUS_NO_SCAN);
124 			}
125 
126 			(void) vs_icap_scan_file(&conn, devname, fname,
127 			    fattr->vsa_size, flags, &result);
128 		}
129 
130 		/* if no error, clear error state on engine and break */
131 		if ((result.vsr_rc != VS_RESULT_SE_ERROR) &&
132 		    (result.vsr_rc != VS_RESULT_ERROR)) {
133 			vs_eng_set_error(&conn, 0);
134 			vs_eng_release(&conn);
135 			break;
136 		}
137 
138 		/* treat error on shutdown as scan not required */
139 		if (vscand_get_state() == VS_STATE_SHUTDOWN) {
140 			vs_eng_release(&conn);
141 			return (VS_STATUS_NO_SCAN);
142 		}
143 
144 		/* set engine's error state and update engine stats */
145 		if (result.vsr_rc == VS_RESULT_SE_ERROR) {
146 			vs_eng_set_error(&conn, 1);
147 			vs_stats_eng_err(conn.vsc_engid);
148 		}
149 		vs_eng_release(&conn);
150 	}
151 
152 	vs_stats_set(result.vsr_rc);
153 
154 	/*
155 	 * VS_RESULT_CLEANED - file infected, cleaned data available
156 	 * VS_RESULT_FORBIDDEN - file infected, no cleaned data
157 	 * Log virus, write audit record and return INFECTED status
158 	 */
159 	if (result.vsr_rc == VS_RESULT_CLEANED ||
160 	    result.vsr_rc == VS_RESULT_FORBIDDEN) {
161 		vs_svc_vlog(fname, &result);
162 		vs_svc_audit(fname, &result);
163 		return (VS_STATUS_INFECTED);
164 	}
165 
166 	/* VS_RESULT_CLEAN - Set the scanstamp and return CLEAN status */
167 	if (result.vsr_rc == VS_RESULT_CLEAN) {
168 		(void) strlcpy(*scanstamp, result.vsr_scanstamp,
169 		    sizeof (vs_scanstamp_t));
170 		return (VS_STATUS_CLEAN);
171 	}
172 
173 	return (VS_STATUS_ERROR);
174 }
175 
176 
177 /*
178  * vs_svc_vlog
179  *
180  * log details of infections detected in file
181  * If virus log is not configured  or cannot be opened, use syslog.
182  */
183 static void
184 vs_svc_vlog(char *filepath, vs_result_t *result)
185 {
186 	FILE *fp = NULL;
187 	time_t sec;
188 	struct tm *timestamp;
189 	char timebuf[18]; /* MM/DD/YY hh:mm:ss */
190 	int i;
191 	char *log;
192 
193 	if ((log = vscand_viruslog()) != NULL)
194 		fp = fopen(log, "a");
195 
196 	if (fp) {
197 		(void) time(&sec);
198 		timestamp = localtime(&sec);
199 		(void) strftime(timebuf, sizeof (timebuf), "%D %T", timestamp);
200 	}
201 
202 	if (result->vsr_nviolations == 0) {
203 		if (fp) {
204 			(void) fprintf(fp, "%s quarantine %s",
205 			    timebuf, filepath);
206 		} else {
207 			syslog(LOG_WARNING, "quarantine %s\n", filepath);
208 		}
209 	} else {
210 		for (i = 0; i < result->vsr_nviolations; i++) {
211 			if (fp) {
212 				(void) fprintf(fp, "%s quarantine %s %d - %s\n",
213 				    timebuf, filepath,
214 				    result->vsr_vrec[i].vr_id,
215 				    result->vsr_vrec[i].vr_desc);
216 			} else {
217 				syslog(LOG_WARNING, "quarantine %s %d - %s\n",
218 				    filepath,
219 				    result->vsr_vrec[i].vr_id,
220 				    result->vsr_vrec[i].vr_desc);
221 			}
222 		}
223 	}
224 
225 	if (fp)
226 		(void) fclose(fp);
227 }
228 
229 
230 /*
231  * vs_svc_audit
232  *
233  * Generate AUE_vscan_quarantine audit record containing name
234  * of infected file, and violation details if available.
235  */
236 static void
237 vs_svc_audit(char *filepath, vs_result_t *result)
238 {
239 	int i;
240 	char *violations[VS_MAX_VIOLATIONS];
241 	char data[VS_MAX_VIOLATIONS][VS_DESCRIPTION_MAX];
242 	adt_session_data_t *ah;
243 	adt_termid_t *p_tid;
244 	adt_event_data_t *event;
245 
246 	if (adt_start_session(&ah, NULL, ADT_USE_PROC_DATA)) {
247 		syslog(LOG_AUTH | LOG_ALERT, "adt_start_session: %m");
248 		return;
249 	}
250 
251 	if (adt_load_ttyname("/dev/console", &p_tid) != 0) {
252 		syslog(LOG_AUTH | LOG_ALERT,
253 		    "adt_load_ttyname(/dev/console): %m");
254 		return;
255 	}
256 
257 	if (adt_set_user(ah, ADT_NO_ATTRIB, ADT_NO_ATTRIB, ADT_NO_ATTRIB,
258 	    ADT_NO_ATTRIB, p_tid, ADT_NEW) != 0) {
259 		syslog(LOG_AUTH | LOG_ALERT, "adt_set_user(ADT_NO_ATTRIB): %m");
260 		(void) adt_end_session(ah);
261 		return;
262 	}
263 
264 	if ((event = adt_alloc_event(ah, ADT_vscan_quarantine)) == NULL) {
265 		syslog(LOG_AUTH | LOG_ALERT,
266 		    "adt_alloc_event(ADT_vscan_quarantine)): %m");
267 		(void) adt_end_session(ah);
268 		return;
269 	}
270 
271 	/* populate vscan audit event */
272 	event->adt_vscan_quarantine.file = filepath;
273 	for (i = 0; i < result->vsr_nviolations; i++) {
274 		(void) snprintf(data[i], VS_DESCRIPTION_MAX, "%d - %s",
275 		    result->vsr_vrec[i].vr_id, result->vsr_vrec[i].vr_desc);
276 		violations[i] = data[i];
277 	}
278 
279 	event->adt_vscan_quarantine.violations = (char **)violations;
280 	event->adt_vscan_quarantine.nviolations = result->vsr_nviolations;
281 
282 	if (adt_put_event(event, ADT_SUCCESS, ADT_SUCCESS))
283 		syslog(LOG_AUTH | LOG_ALERT, "adt_put_event: %m");
284 
285 	adt_free_event(event);
286 	(void) adt_end_session(ah);
287 }
288