aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/auditfilter.c
diff options
context:
space:
mode:
authorAmy Griffis <amy.griffis@hp.com>2006-06-14 18:45:21 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2006-07-01 05:43:06 -0400
commit5adc8a6adc91c4c85a64c75a70a619fffc924817 (patch)
treeace9af6bbc3cf711f43cfd88e834baeb6989ca3f /kernel/auditfilter.c
parent9262e9149f346a5443300f8c451b8e7631e81a42 (diff)
[PATCH] add rule filterkey
Add support for a rule key, which can be used to tie audit records to audit rules. This is useful when a watched file is accessed through a link or symlink, as well as for general audit log analysis. Because this patch uses a string key instead of an integer key, there is a bit of extra overhead to do the kstrdup() when a rule fires. However, we're also allocating memory for the audit record buffer, so it's probably not that significant. I went ahead with a string key because it seems more user-friendly. Note that the user must ensure that filterkeys are unique. The kernel only checks for duplicate rules. Signed-off-by: Amy Griffis <amy.griffis@hpd.com>
Diffstat (limited to 'kernel/auditfilter.c')
-rw-r--r--kernel/auditfilter.c95
1 files changed, 59 insertions, 36 deletions
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 4c99d2c586ed..e98db08fc6df 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -141,6 +141,7 @@ static inline void audit_free_rule(struct audit_entry *e)
selinux_audit_rule_free(f->se_rule);
}
kfree(e->rule.fields);
+ kfree(e->rule.filterkey);
kfree(e);
}
@@ -511,6 +512,16 @@ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
if (err)
goto exit_free;
break;
+ case AUDIT_FILTERKEY:
+ err = -EINVAL;
+ if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN)
+ goto exit_free;
+ str = audit_unpack_string(&bufp, &remain, f->val);
+ if (IS_ERR(str))
+ goto exit_free;
+ entry->rule.buflen += f->val;
+ entry->rule.filterkey = str;
+ break;
default:
goto exit_free;
}
@@ -612,6 +623,10 @@ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
data->buflen += data->values[i] =
audit_pack_string(&bufp, krule->watch->path);
break;
+ case AUDIT_FILTERKEY:
+ data->buflen += data->values[i] =
+ audit_pack_string(&bufp, krule->filterkey);
+ break;
default:
data->values[i] = f->val;
}
@@ -651,6 +666,11 @@ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
if (strcmp(a->watch->path, b->watch->path))
return 1;
break;
+ case AUDIT_FILTERKEY:
+ /* both filterkeys exist based on above type compare */
+ if (strcmp(a->filterkey, b->filterkey))
+ return 1;
+ break;
default:
if (a->fields[i].val != b->fields[i].val)
return 1;
@@ -730,6 +750,7 @@ static struct audit_entry *audit_dupe_rule(struct audit_krule *old,
u32 fcount = old->field_count;
struct audit_entry *entry;
struct audit_krule *new;
+ char *fk;
int i, err = 0;
entry = audit_init_entry(fcount);
@@ -760,6 +781,13 @@ static struct audit_entry *audit_dupe_rule(struct audit_krule *old,
case AUDIT_SE_CLR:
err = audit_dupe_selinux_field(&new->fields[i],
&old->fields[i]);
+ break;
+ case AUDIT_FILTERKEY:
+ fk = kstrdup(old->filterkey, GFP_KERNEL);
+ if (unlikely(!fk))
+ err = -ENOMEM;
+ else
+ new->filterkey = fk;
}
if (err) {
audit_free_rule(entry);
@@ -1245,6 +1273,34 @@ static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
skb_queue_tail(q, skb);
}
+/* Log rule additions and removals */
+static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action,
+ struct audit_krule *rule, int res)
+{
+ struct audit_buffer *ab;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+ if (!ab)
+ return;
+ audit_log_format(ab, "auid=%u", loginuid);
+ if (sid) {
+ char *ctx = NULL;
+ u32 len;
+ if (selinux_ctxid_to_string(sid, &ctx, &len))
+ audit_log_format(ab, " ssid=%u", sid);
+ else
+ audit_log_format(ab, " subj=%s", ctx);
+ kfree(ctx);
+ }
+ audit_log_format(ab, " %s rule key=", action);
+ if (rule->filterkey)
+ audit_log_untrustedstring(ab, rule->filterkey);
+ else
+ audit_log_format(ab, "(null)");
+ audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
+ audit_log_end(ab);
+}
+
/**
* audit_receive_filter - apply all rules to the specified message type
* @type: audit message type
@@ -1304,24 +1360,7 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
err = audit_add_rule(entry,
&audit_filter_list[entry->rule.listnr]);
-
- if (sid) {
- char *ctx = NULL;
- u32 len;
- if (selinux_ctxid_to_string(sid, &ctx, &len)) {
- /* Maybe call audit_panic? */
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u ssid=%u add rule to list=%d res=%d",
- loginuid, sid, entry->rule.listnr, !err);
- } else
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u subj=%s add rule to list=%d res=%d",
- loginuid, ctx, entry->rule.listnr, !err);
- kfree(ctx);
- } else
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u add rule to list=%d res=%d",
- loginuid, entry->rule.listnr, !err);
+ audit_log_rule_change(loginuid, sid, "add", &entry->rule, !err);
if (err)
audit_free_rule(entry);
@@ -1337,24 +1376,8 @@ int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
err = audit_del_rule(entry,
&audit_filter_list[entry->rule.listnr]);
-
- if (sid) {
- char *ctx = NULL;
- u32 len;
- if (selinux_ctxid_to_string(sid, &ctx, &len)) {
- /* Maybe call audit_panic? */
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u ssid=%u remove rule from list=%d res=%d",
- loginuid, sid, entry->rule.listnr, !err);
- } else
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u subj=%s remove rule from list=%d res=%d",
- loginuid, ctx, entry->rule.listnr, !err);
- kfree(ctx);
- } else
- audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
- "auid=%u remove rule from list=%d res=%d",
- loginuid, entry->rule.listnr, !err);
+ audit_log_rule_change(loginuid, sid, "remove", &entry->rule,
+ !err);
audit_free_rule(entry);
break;

Privacy Policy