769 |
|
|
770 |
@ Allow reuse of memory allocated for domain policy. |
@ Allow reuse of memory allocated for domain policy. |
771 |
|
|
772 |
As with domain policy, unlike other policies, didn't have |
Regarding domain policy, unlike other policies, didn't have |
773 |
"is_deleted" flag and new memory were allocated |
"is_deleted" flag and new memory were allocated |
774 |
if the deleted entries are given again. |
if the deleted entries are given again. |
775 |
But to allow administrators switch domain policy periodically, |
But to allow administrators switch domain policy periodically, |
933 |
|
|
934 |
@ Fix ReadAddressGroupPolicy() bug. |
@ Fix ReadAddressGroupPolicy() bug. |
935 |
|
|
936 |
ReadAddressGroupPolicy() fails if both "path_group" and "address_group" are used |
ReadAddressGroupPolicy() fails if both "path_group" and "address_group" |
937 |
because I forgot to set "head->read_var1 = NULL". |
are used because I forgot to set "head->read_var1 = NULL". |
938 |
|
|
939 |
Fix 2007/07/10 |
Fix 2007/07/10 |
940 |
|
|
949 |
|
|
950 |
@ Remove mount-flags manipulation. |
@ Remove mount-flags manipulation. |
951 |
|
|
952 |
Until now, administrator is permitted to turn on/off specific mount options |
Until now, administrator is permitted to turn on/off specific mount |
953 |
regardless of mount options passed to kernel. |
options regardless of mount options passed to kernel. |
954 |
I removed this feature because "exact option matching" sounds better than |
I removed this feature because "exact option matching" sounds better than |
955 |
"automatic option enabler/disabler". |
"automatic option enabler/disabler". |
956 |
|
|
957 |
@ Remove /proc/ccs/info/mapping . |
@ Remove /proc/ccs/info/mapping . |
958 |
|
|
959 |
I removed /proc/ccs/info/mapping because nobody seems to use this feature. |
I removed /proc/ccs/info/mapping because nobody seems to use this |
960 |
|
feature. |
961 |
|
|
962 |
@ Call external policy loader automatically. |
@ Call external policy loader automatically. |
963 |
|
|
981 |
can handle interactive operations by opening /dev/console . |
can handle interactive operations by opening /dev/console . |
982 |
Now, there is no difference between init=/sbin/ccs-init and |
Now, there is no difference between init=/sbin/ccs-init and |
983 |
call_usermodehelper("/sbin/ccs-init"), and users no longer need to |
call_usermodehelper("/sbin/ccs-init"), and users no longer need to |
984 |
add init=/sbin/ccs-init parameter to load policy before /sbin/init starts. |
add init=/sbin/ccs-init parameter to load policy before /sbin/init |
985 |
|
starts. |
986 |
|
|
987 |
Fix 2007/08/14 |
Fix 2007/08/14 |
988 |
|
|
1042 |
|
|
1043 |
Now, quota checking is done before getting domain_acl_lock lock. |
Now, quota checking is done before getting domain_acl_lock lock. |
1044 |
This may exceed quota by one or two entries, but that won't matter. |
This may exceed quota by one or two entries, but that won't matter. |
1045 |
|
|
1046 |
|
Fix 2007/10/16 |
1047 |
|
|
1048 |
|
@ Add environment variable check. |
1049 |
|
|
1050 |
|
There are environment variables that may cause dangerous behavior |
1051 |
|
like LD_\* . |
1052 |
|
So I introduced 'allow_env' directive that allows specified |
1053 |
|
environment variable inherited to next domain. |
1054 |
|
Unlike other permissions, this check is done at execve() time |
1055 |
|
using next domain's ACL information. |
1056 |
|
|
1057 |
|
To manage commonly inherited environments like PATH , |
1058 |
|
you can use 'allow_env' directive in exception policy |
1059 |
|
to globally grant specified environment variable. |
1060 |
|
|
1061 |
|
Fix 2007/11/05 |
1062 |
|
|
1063 |
|
@ Replace semaphore with mutex. |
1064 |
|
|
1065 |
|
I replaced semaphore with mutex. |
1066 |
|
|
1067 |
|
@ Add missing down() in AddReservedEntry(). |
1068 |
|
|
1069 |
|
Mutex debugging capability told me that I had forgotten to call down() |
1070 |
|
since TOMOYO version 1.3.2 . |
1071 |
|
This function is not called by learning mode, |
1072 |
|
so the semaphore's counter will not overflow for normal usage. |
1073 |
|
|
1074 |
|
Fix 2005/11/27 |
1075 |
|
|
1076 |
|
@ Fix ReadTable() truncation bug. |
1077 |
|
|
1078 |
|
"snprintf(str, size, format, ...) >= size" means truncated. |
1079 |
|
But I was checking for "snprintf(str, size, format, ...) > size". |
1080 |
|
As a result, some entries might be dumped without '\n'. |
1081 |
|
|
1082 |
|
@ Purge direct "->prev"/"->next" manipulation. |
1083 |
|
|
1084 |
|
All list manipulations use "struct list_head" or "struct list1_head". |
1085 |
|
"struct list1_head" doesn't have "->prev" member to save memory usage. |
1086 |
|
|
1087 |
|
Fix 2007/11/29 |
1088 |
|
|
1089 |
|
@ Add missing semaphore in GetEXE(). |
1090 |
|
|
1091 |
|
mm->mmap_sem was missing. |
1092 |
|
|
1093 |
|
Fix 2007/12/17 |
1094 |
|
|
1095 |
|
@ Remove unused EXPORT_SYMBOL(). |
1096 |
|
|
1097 |
|
Mark some functions static. |
1098 |
|
|
1099 |
|
Fix 2007/12/18 |
1100 |
|
|
1101 |
|
@ Fix AddMountACL() rejection bug. |
1102 |
|
|
1103 |
|
To my surprise, "mount --bind source dest" accepts |
1104 |
|
not only "both source and dest are directory" |
1105 |
|
but also "both source and dest are non-directory". |
1106 |
|
I was rejecting if dest is not a directory in AddMountACL(). |
1107 |
|
|
1108 |
|
@ Change log format. |
1109 |
|
|
1110 |
|
Profile number and mode is added in audit logs. |
1111 |
|
|
1112 |
|
Fix 2008/01/03 |
1113 |
|
|
1114 |
|
@ Change directive for file's read/write/execute permission. |
1115 |
|
|
1116 |
|
Directives for file's read/write/execute permissions were |
1117 |
|
4/2/1 respectively. But for easier understanding, they are now |
1118 |
|
replaced by read/write/execute (e.g. "allow_read" instead of "4"). |
1119 |
|
But for easier inputting, 4/2/1 are still accepted instead of |
1120 |
|
allow_read/allow_write/allow_execute respectively. |
1121 |
|
|
1122 |
|
@ Change internal data structure. |
1123 |
|
|
1124 |
|
Since I don't have more than 16 types of file permissions, |
1125 |
|
I combined them using bit-fields. |
1126 |
|
|
1127 |
|
Each entry had a field for conditional permission support. |
1128 |
|
But since this field is unlikely used, I separated the field from |
1129 |
|
common part. |
1130 |
|
|
1131 |
|
These changes will reduce memory used by policy. |
1132 |
|
|
1133 |
|
Fix 2008/01/15 |
1134 |
|
|
1135 |
|
@ Add ptrace() hook. |
1136 |
|
|
1137 |
|
To prevent attackers from controlling important processes using |
1138 |
|
ptrace(), I added a hook for ptrace(). |
1139 |
|
Most programs (except strace(1) and gdb(1)) won't use ptrace(2). |
1140 |
|
|
1141 |
|
@ Fix sleep condition check in CheckSocketRecvDatagramPermission(). |
1142 |
|
|
1143 |
|
It seems that correct method to use is in_atomic() |
1144 |
|
rather than in_interrupt() because in_atomic() returns nonzero |
1145 |
|
whenever scheduling is not allowed. |
1146 |
|
|
1147 |
|
Fix 2008/02/05 |
1148 |
|
|
1149 |
|
@ Use find_task_by_vpid() instead of find_task_pid(). |
1150 |
|
|
1151 |
|
Kernel 2.6.24 introduced PID namespace. |
1152 |
|
To search PID given from userland, the kernel needs to use |
1153 |
|
find_task_by_vpid() instead of find_task_pid(). |
1154 |
|
|
1155 |
|
Fix 2008/02/14 |
1156 |
|
|
1157 |
|
@ Add execve() parameter checking. |
1158 |
|
|
1159 |
|
Until now, it was impossible to check argv[] and envp[] parameters |
1160 |
|
passed to execve(). |
1161 |
|
I expanded conditional permission syntax so that |
1162 |
|
{ argc, envc, argv[] , envp[] } parameters can be checked if needed. |
1163 |
|
This will allow administrator permit execution of /bin/sh only when |
1164 |
|
/bin/sh is invoked in the form of "/bin/sh -c" and environment variable |
1165 |
|
HOME is set by specifying |
1166 |
|
|
1167 |
|
allow_execute /bin/sh if exec.argv[1]="-c" exec.envp["HOME"]!=NULL |
1168 |
|
|
1169 |
|
in the policy. |
1170 |
|
This extension will make exploit codes difficult to start /bin/sh because |
1171 |
|
they unlikely set up environment variables and unlikely specify "-c" |
1172 |
|
option when invoking /bin/sh , whereas proper functions likely set up |
1173 |
|
environment variables and likely specify "-c" option. |
1174 |
|
|
1175 |
|
Fix 2008/02/18 |
1176 |
|
|
1177 |
|
@ Add process state checking. |
1178 |
|
|
1179 |
|
Until now, it was impossible to change ACL without executing program. |
1180 |
|
I added three variables for performing stateful checking within a domain. |
1181 |
|
You can set current process's state like: |
1182 |
|
|
1183 |
|
allow_network TCP accept @TRUSTED_HOSTS 1024-65535 ; set task.state[0]=1 |
1184 |
|
allow_network TCP accept @UNTRUSTED_HOSTS 1024-65535 ; set task.state[0]=0 |
1185 |
|
|
1186 |
|
and you can use the state like |
1187 |
|
|
1188 |
|
allow_read /path/to/important/file if task.state[0]=1 |
1189 |
|
|
1190 |
|
in the policy. |
1191 |
|
The state changes when the request was granted by the MAC's policy, |
1192 |
|
so please be careful with situations where the state has changed |
1193 |
|
successfully but the request was not processed because of other reasons |
1194 |
|
(e.g. out of memory). |
1195 |
|
|
1196 |
|
Fix 2008/02/26 |
1197 |
|
|
1198 |
|
@ Support /proc/ccs/ access by non-root user. |
1199 |
|
|
1200 |
|
Until now, only root user can access /proc/ccs/ interface. |
1201 |
|
But to permit /proc/ccs/ access by non-root user so that it won't require |
1202 |
|
ssh login by root user when administrating from remote host, |
1203 |
|
I made "(current->uid == 0 && current->euid == 0)" requirement optional. |
1204 |
|
If this requirement is disabled, only "conventional DAC permission |
1205 |
|
checks" and "/proc/ccs/manager checks" are used. |
1206 |
|
|
1207 |
|
Fix 2008/02/29 |
1208 |
|
|
1209 |
|
@ Add sleep_on_violation feature. |
1210 |
|
|
1211 |
|
Some exploit codes (e.g. trans2open for Samba) continue running |
1212 |
|
until it achieves the purpose of the exploit code (e.g. invoke /bin/sh). |
1213 |
|
|
1214 |
|
If such code is injected due to buffer overflow but the kernel |
1215 |
|
rejects the request, it triggers infinite "Permission denied" loop. |
1216 |
|
As a result, the CPU usage becomes 100% and gives bad effects to |
1217 |
|
the rest of processes. |
1218 |
|
This is a side effect of rejecting the request from the exploit code |
1219 |
|
which wouldn't happen if the request from the exploit code was granted. |
1220 |
|
|
1221 |
|
To avoid such CPU consumption, I added a penalty that forcibly |
1222 |
|
sleeps for specified period when a request is rejected. |
1223 |
|
|
1224 |
|
This penalty doesn't work if the exploit code does nothing but |
1225 |
|
continue running, but I think most exploit code's purpose is |
1226 |
|
to start some program rather than to slow down the target system. |
1227 |
|
|
1228 |
|
@ Add alt_exec feature. |
1229 |
|
|
1230 |
|
Since TOMOYO Linux's approach is "know all essential requests in advance |
1231 |
|
and create policy that permits only them", you can regard anomalous |
1232 |
|
requests as attacks (if you want to do so). |
1233 |
|
|
1234 |
|
Common MAC implementations merely reject requests that violate policy. |
1235 |
|
But I added a special handler for execve() to TOMOYO Linux. |
1236 |
|
|
1237 |
|
This handler is triggered when a process requested to execute a program |
1238 |
|
but the request was rejected by the policy. |
1239 |
|
This handler executes a program specified by the administrator |
1240 |
|
instead of a program requested by the process. |
1241 |
|
|
1242 |
|
Most attackers attempt to execute /bin/sh to start something malicious. |
1243 |
|
Attackers execute an exploit code using buffer overflow vulnerability |
1244 |
|
to steal control of a process. But this handler can get back control |
1245 |
|
if an exploit code requests execve() that is not permitted by policy. |
1246 |
|
|
1247 |
|
By default, this handler does nothing (i.e. merely reject execve() |
1248 |
|
request). You can specify any program to start what you want to do. |
1249 |
|
|
1250 |
|
You can redirect attackers to somewhere else (e.g. honeypot). |
1251 |
|
This makes it possible to act your Linux box as an on-demand honeypot |
1252 |
|
while keeping regular services for your usage. |
1253 |
|
|
1254 |
|
You can collect information of the attacker (e.g. IP address) and |
1255 |
|
update firewall configuration. |
1256 |
|
|
1257 |
|
You can silently terminate a process who requested execve() |
1258 |
|
that is not permitted by policy. |
1259 |
|
|
1260 |
|
Fix 2008/03/03 |
1261 |
|
|
1262 |
|
@ Add "force_alt_exec" keyword. |
1263 |
|
|
1264 |
|
To be able to fully utilize "alt_exec" feature, |
1265 |
|
I added "force_alt_exec" keyword so that |
1266 |
|
all execute requests are replaced by the execute request of a program |
1267 |
|
specified by alt_exec feature. |
1268 |
|
|
1269 |
|
If this keyword is specified for a domain, the domain no longer |
1270 |
|
executes any programs regardless of the mode of file access control |
1271 |
|
(i.e. the domain won't execute even if MAC_FOR_FILE=0 ). |
1272 |
|
Instead, the domain executes the program specified by alt_exec feature |
1273 |
|
and the program specified by alt_exec feature validates the execute |
1274 |
|
request and executes it if it is appropriate to execute. |
1275 |
|
|
1276 |
|
If you can tolerate that there is no chance to return an error code |
1277 |
|
to the caller to tell the execute request was rejected, |
1278 |
|
this is more flexible approach than in-kernel execve() parameter |
1279 |
|
checking because we can do argv[] and envp[] checking easily. |
1280 |
|
|
1281 |
|
Fix 2008/03/04 |
1282 |
|
|
1283 |
|
@ Use string for access control mode. |
1284 |
|
|
1285 |
|
An integer expression for access control mode sometimes confuses |
1286 |
|
administrators because profile number is also an integer expression. |
1287 |
|
To avoid confusion between profile number and access control mode, |
1288 |
|
I introduced a string expression for access control mode. |
1289 |
|
|
1290 |
|
Modes which take an integer between 0 and 3. |
1291 |
|
|
1292 |
|
0 -> disabled |
1293 |
|
1 -> learning |
1294 |
|
2 -> permissive |
1295 |
|
3 -> enforcing |
1296 |
|
|
1297 |
|
Modes which take 0 or 1. |
1298 |
|
|
1299 |
|
0 -> disabled |
1300 |
|
1 -> enabled |
1301 |
|
|
1302 |
|
Fix 2008/03/10 |
1303 |
|
|
1304 |
|
@ Rename "force_alt_exec" keyword to "preferred_execute_handler". |
1305 |
|
|
1306 |
|
To be able to use different programs for validating execve() parameters, |
1307 |
|
I moved the location to specify the program's pathname from profile |
1308 |
|
to domain policy. |
1309 |
|
|
1310 |
|
The "preferred_execute_handler" keyword takes one pathname which is |
1311 |
|
invoked whenever execve() request is issued. Thus, any "allow_execute" |
1312 |
|
keywords in a domain with "preferred_execute_handler" are ignored. |
1313 |
|
This keyword is designed for validating expected/desirable execve() |
1314 |
|
requests in userspace, although there is no way to tell the caller |
1315 |
|
that the execve() request was rejected. |
1316 |
|
|
1317 |
|
@ Rename "alt_exec" keyword to "default_execute_handler". |
1318 |
|
|
1319 |
|
The "default_execute_handler" keyword takes one pathname which is |
1320 |
|
invoked only when execve() request was rejected. In other words, |
1321 |
|
this program is invoked only when the following conditions are met. |
1322 |
|
|
1323 |
|
(1) None of "allow_execute" keywords in the domain didn't match. |
1324 |
|
(2) The execve() request was rejected in enforcing mode. |
1325 |
|
(3) "preferred_execute_handler" keyword is not used by the domain. |
1326 |
|
|
1327 |
|
This keyword is designed for handling unexpected/undesirable execve() |
1328 |
|
requests, to redirect the process issuing such requests to somewhere. |