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
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
|
/* Copyright (C) 2007-2010 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Gurvinder Singh <gurvindersinghdahiya@gmail.com>
*
* File to drop the engine capabilities using libcap-ng by
* Steve Grubb
*/
#ifndef OS_WIN32
#include "suricata-common.h"
#include "util-debug.h"
#include "suricata.h"
#include "util-privs.h"
#include "util-byte.h"
#ifdef HAVE_LIBCAP_NG
#include <cap-ng.h>
#ifdef HAVE_SYS_PRCTL_H
#include <sys/prctl.h>
#endif
#include "threadvars.h"
#include "util-cpu.h"
#include "runmodes.h"
/** flag indicating if we'll be using caps */
extern int sc_set_caps;
/** our current runmode */
extern int run_mode;
/**
* \brief Drop the privileges of the main thread
*/
void SCDropMainThreadCaps(uint32_t userid, uint32_t groupid)
{
if (sc_set_caps == FALSE)
return;
capng_clear(CAPNG_SELECT_BOTH);
switch (run_mode) {
case RUNMODE_PCAP_DEV:
case RUNMODE_AFP_DEV:
case RUNMODE_AFXDP_DEV:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_RAW, /* needed for pcap live mode */
CAP_SYS_NICE,
CAP_NET_ADMIN,
-1);
break;
case RUNMODE_PFRING:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_ADMIN, CAP_NET_RAW, CAP_SYS_NICE,
-1);
break;
case RUNMODE_NFLOG:
case RUNMODE_NFQ:
capng_updatev(CAPNG_ADD, CAPNG_EFFECTIVE|CAPNG_PERMITTED,
CAP_NET_ADMIN, /* needed for nflog and nfqueue inline mode */
CAP_SYS_NICE,
-1);
break;
}
if (capng_change_id(userid, groupid, CAPNG_DROP_SUPP_GRP |
CAPNG_CLEAR_BOUNDING) < 0)
{
FatalError("capng_change_id for main thread"
" failed");
}
SCLogInfo("dropped the caps for main thread");
}
void SCDropCaps(ThreadVars *tv)
{
#if 0
capng_clear(CAPNG_SELECT_BOTH);
capng_apply(CAPNG_SELECT_BOTH);
if (tv->cap_flags & SC_CAP_IPC_LOCK) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_IPC_LOCK);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_IPC_LOCK has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_ADMIN) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_ADMIN);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_ADMIN has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_BIND_SERVICE) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_BIND_SERVICE);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_BIND_SERVICE has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_BROADCAST) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_BROADCAST);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_BROADCAST has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_NET_RAW) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_NET_RAW);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_NET_RAW has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_SYS_ADMIN) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_SYS_ADMIN);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_SYS_ADMIN has been set", tv->name);
}
if (tv->cap_flags & SC_CAP_SYS_RAW_IO) {
capng_update(CAPNG_ADD, (capng_type_t) (CAPNG_EFFECTIVE | CAPNG_PERMITTED), CAP_SYS_RAWIO);
capng_apply(CAPNG_SELECT_CAPS);
SCLogDebug("For thread \"%s\" CAP_SYS_RAWIO has been set", tv->name);
}
#endif
}
#endif /* HAVE_LIBCAP_NG */
/**
* \brief Function to get the user and group ID from the specified user name
*
* \param user_name pointer to the given user name
* \param uid pointer to the user id in which result will be stored
* \param gid pointer to the group id in which result will be stored
*
* \retval FatalError on a failure
*/
void SCGetUserID(const char *user_name, const char *group_name, uint32_t *uid, uint32_t *gid)
{
uint32_t userid = 0;
uint32_t groupid = 0;
struct passwd *pw;
if (user_name == NULL || strlen(user_name) == 0) {
FatalError("no user name was provided - ensure it is specified either in the configuration "
"file (run-as.user) or in command-line arguments (--user)");
}
/* Get the user ID */
if (isdigit((unsigned char)user_name[0]) != 0) {
if (ByteExtractStringUint32(&userid, 10, 0, (const char *)user_name) < 0) {
FatalError("invalid user id value: '%s'", user_name);
}
pw = getpwuid(userid);
if (pw == NULL) {
FatalError("unable to get the user ID, "
"check if user exist!!");
}
} else {
pw = getpwnam(user_name);
if (pw == NULL) {
FatalError("unable to get the user ID, "
"check if user exist!!");
}
userid = pw->pw_uid;
}
/* Get the group ID */
if (group_name != NULL) {
struct group *gp;
if (isdigit((unsigned char)group_name[0]) != 0) {
if (ByteExtractStringUint32(&groupid, 10, 0, (const char *)group_name) < 0) {
FatalError("invalid group id: '%s'", group_name);
}
} else {
gp = getgrnam(group_name);
if (gp == NULL) {
FatalError("unable to get the group"
" ID, check if group exist!!");
}
groupid = gp->gr_gid;
}
} else {
groupid = pw->pw_gid;
}
/* close the group database */
endgrent();
/* close the user database */
endpwent();
*uid = userid;
*gid = groupid;
}
/**
* \brief Function to get the group ID from the specified group name
*
* \param group_name pointer to the given group name
* \param gid pointer to the group id in which result will be stored
*
* \retval FatalError on a failure
*/
void SCGetGroupID(const char *group_name, uint32_t *gid)
{
uint32_t grpid = 0;
struct group *gp;
if (group_name == NULL || strlen(group_name) == 0) {
FatalError("no group name was provided - ensure it is specified either in the "
"configuration file (run-as.group) or in command-line arguments (--group)");
}
/* Get the group ID */
if (isdigit((unsigned char)group_name[0]) != 0) {
if (ByteExtractStringUint32(&grpid, 10, 0, (const char *)group_name) < 0) {
FatalError("invalid group id: '%s'", group_name);
}
} else {
gp = getgrnam(group_name);
if (gp == NULL) {
FatalError("unable to get the group ID,"
" check if group exist!!");
}
grpid = gp->gr_gid;
}
/* close the group database */
endgrent();
*gid = grpid;
}
#ifdef __OpenBSD__
int SCPledge(void)
{
int ret = pledge("stdio rpath wpath cpath fattr unix dns bpf", NULL);
if (ret != 0) {
SCLogError("unable to pledge,"
" check permissions!! ret=%i errno=%i",
ret, errno);
exit(EXIT_FAILURE);
}
return 0;
}
#endif /* __OpenBSD__ */
#endif /* OS_WIN32 */
|
