}
}
-static bool is_matching_name_request(sd_bus_message *m, const char *name, bool prefix) {
-
- char *n = NULL;
- int r;
-
- if (!sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "RequestName"))
- return false;
+enum {
+ DENY,
+ ALLOW,
+ DUNNO,
+};
- r = sd_bus_message_read(m, "s", &n);
- if (r < 0)
- return false;
+static const char *verdict_to_string(int v) {
+ switch (v) {
- r = sd_bus_message_rewind(m, true);
- if (r < 0)
- return false;
+ case DENY:
+ return "DENY";
+ case ALLOW:
+ return "ALLOW";
+ case DUNNO:
+ return "DUNNO";
+ }
- if (prefix)
- return startswith(name, n);
- else
- return streq_ptr(name, n);
+ return NULL;
}
-static bool is_matching_call(PolicyItem *i, sd_bus_message *m, const char *name) {
+struct policy_check_filter {
+ PolicyItemClass class;
+ uid_t uid;
+ gid_t gid;
+ int message_type;
+ const char *name;
+ const char *interface;
+ const char *path;
+ const char *member;
+};
- if (i->message_type && (i->message_type != m->header->type))
- return false;
+static int is_permissive(PolicyItem *i) {
- if (i->path && (!m->path || !streq(i->path, m->path)))
- return false;
+ assert(i);
- if (i->member && (!m->member || !streq(i->member, m->member)))
- return false;
+ return (i->type == POLICY_ITEM_ALLOW) ? ALLOW : DENY;
+}
- if (i->interface && (!m->interface || !streq(i->interface, m->interface)))
- return false;
+static int check_policy_item(PolicyItem *i, const struct policy_check_filter *filter) {
- if (i->name && (!name || !streq(i->name, name)))
- return false;
+ assert(i);
+ assert(filter);
- return true;
-}
+ switch (i->class) {
+ case POLICY_ITEM_SEND:
+ case POLICY_ITEM_RECV:
-enum {
- ALLOW,
- DUNNO,
- DENY,
-};
+ if (i->name && !streq_ptr(i->name, filter->name))
+ break;
-static int is_permissive(PolicyItem *i) {
+ if ((i->message_type != 0) && (i->message_type != filter->message_type))
+ break;
- return (i->type == POLICY_ITEM_ALLOW) ? ALLOW : DENY;
-}
+ if (i->path && !streq_ptr(i->path, filter->path))
+ break;
-static int check_policy_item(PolicyItem *i, sd_bus_message *m, const struct ucred *ucred) {
+ if (i->member && !streq_ptr(i->member, filter->member))
+ break;
- switch (i->class) {
- case POLICY_ITEM_SEND:
- if ((m->bus->is_kernel && is_matching_call(i, m, m->destination)) ||
- (!m->bus->is_kernel && is_matching_call(i, m, m->sender)))
- return is_permissive(i);
- break;
+ if (i->interface && !streq_ptr(i->interface, filter->interface))
+ break;
- case POLICY_ITEM_RECV:
- if ((m->bus->is_kernel && is_matching_call(i, m, m->sender)) ||
- (!m->bus->is_kernel && is_matching_call(i, m, m->destination)))
- return is_permissive(i);
- break;
+ return is_permissive(i);
case POLICY_ITEM_OWN:
- if (is_matching_name_request(m, i->name, false))
+ assert(filter->name);
+
+ if (streq(i->name, "*") || streq(i->name, filter->name))
return is_permissive(i);
break;
case POLICY_ITEM_OWN_PREFIX:
- if (is_matching_name_request(m, i->name, true))
+ assert(filter->name);
+
+ if (streq(i->name, "*") || service_name_startswith(filter->name, i->name))
return is_permissive(i);
break;
case POLICY_ITEM_USER:
- if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "Hello") &&
- (streq_ptr(i->name, "*") || (i->uid_valid && i->uid == ucred->uid)))
- return is_permissive(i);
+ if (filter->uid != (uid_t) -1)
+ if ((streq_ptr(i->name, "*") || (i->uid_valid && i->uid == filter->uid)))
+ return is_permissive(i);
break;
case POLICY_ITEM_GROUP:
- if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "Hello") &&
- (streq_ptr(i->name, "*") || (i->gid_valid && i->gid == ucred->gid)))
- return is_permissive(i);
+ if (filter->gid != (gid_t) -1)
+ if ((streq_ptr(i->name, "*") || (i->gid_valid && i->gid == filter->gid)))
+ return is_permissive(i);
break;
case POLICY_ITEM_IGNORE:
return DUNNO;
}
-static int check_policy_items(PolicyItem *items, sd_bus_message *m, const struct ucred *ucred) {
+static int check_policy_items(PolicyItem *items, const struct policy_check_filter *filter) {
PolicyItem *i;
- int r, ret = DUNNO;
+ int verdict = DUNNO;
+
+ assert(filter);
/* Check all policies in a set - a broader one might be followed by a more specific one,
* and the order of rules in policy definitions matters */
LIST_FOREACH(items, i, items) {
- r = check_policy_item(i, m, ucred);
- if (r != DUNNO)
- ret = r;
+ int v;
+
+ if (i->class != filter->class &&
+ !(i->class == POLICY_ITEM_OWN_PREFIX && filter->class == POLICY_ITEM_OWN))
+ continue;
+
+ v = check_policy_item(i, filter);
+ if (v != DUNNO)
+ verdict = v;
}
- return ret;
+ return verdict;
}
-bool policy_check(Policy *p, sd_bus_message *m, const struct ucred *ucred) {
+static int policy_check(Policy *p, const struct policy_check_filter *filter) {
PolicyItem *items;
- int r;
+ int verdict, v;
+
+ assert(p);
+ assert(filter);
+
+ assert(IN_SET(filter->class, POLICY_ITEM_SEND, POLICY_ITEM_RECV, POLICY_ITEM_OWN, POLICY_ITEM_USER, POLICY_ITEM_GROUP));
/*
* The policy check is implemented by the following logic:
*
- * 1. Check mandatory items. If the message matches any of these, it is decisive.
- * 2. See if the passed ucred match against the user/group hashmaps. A matching entry is also decisive.
- * 3. Consult the defaults if non of the above matched with a more specific rule.
- * 4. If the message isn't caught be the defaults either, reject it.
+ * 1. Check default items
+ * 2. Check group items
+ * 3. Check user items
+ * 4. Check mandatory items
+ *
+ * Later rules override earlier rules.
*/
- r = check_policy_items(p->mandatory_items, m, ucred);
- if (r != DUNNO)
- return r == ALLOW;
+ verdict = check_policy_items(p->default_items, filter);
- if (ucred->pid > 0) {
- items = hashmap_get(p->user_items, UINT32_TO_PTR(ucred->uid));
+ if (filter->gid != (gid_t) -1) {
+ items = hashmap_get(p->group_items, UINT32_TO_PTR(filter->gid));
if (items) {
- r = check_policy_items(items, m, ucred);
- if (r != DUNNO)
- return r == ALLOW;
+ v = check_policy_items(items, filter);
+ if (v != DUNNO)
+ verdict = v;
}
+ }
- items = hashmap_get(p->group_items, UINT32_TO_PTR(ucred->gid));
+ if (filter->uid != (uid_t) -1) {
+ items = hashmap_get(p->user_items, UINT32_TO_PTR(filter->uid));
if (items) {
- r = check_policy_items(items, m, ucred);
- if (r != DUNNO)
- return r == ALLOW;
+ v = check_policy_items(items, filter);
+ if (v != DUNNO)
+ verdict = v;
}
}
- r = check_policy_items(p->default_items, m, ucred);
- if (r != DUNNO)
- return r == ALLOW;
+ v = check_policy_items(p->mandatory_items, filter);
+ if (v != DUNNO)
+ verdict = v;
+
+ return verdict;
+}
+
+bool policy_check_own(Policy *p, uid_t uid, gid_t gid, const char *name) {
+
+ struct policy_check_filter filter = {
+ .class = POLICY_ITEM_OWN,
+ .uid = uid,
+ .gid = gid,
+ .name = name,
+ };
+
+ int verdict;
+
+ assert(p);
+ assert(name);
+
+ verdict = policy_check(p, &filter);
+
+ log_full(LOG_AUTH | (verdict != ALLOW ? LOG_WARNING : LOG_DEBUG),
+ "Ownership permission check for uid=" UID_FMT " gid=" GID_FMT" name=%s: %s",
+ uid, gid, strna(name), strna(verdict_to_string(verdict)));
+
+ return verdict == ALLOW;
+}
+
+bool policy_check_hello(Policy *p, uid_t uid, gid_t gid) {
+
+ struct policy_check_filter filter = {
+ .uid = uid,
+ .gid = gid,
+ };
+ int verdict;
+
+ assert(p);
+
+ filter.class = POLICY_ITEM_USER;
+ verdict = policy_check(p, &filter);
+
+ if (verdict != DENY) {
+ int v;
+
+ filter.class = POLICY_ITEM_GROUP;
+ v = policy_check(p, &filter);
+ if (v != DUNNO)
+ verdict = v;
+ }
+
+ log_full(LOG_AUTH | (verdict != ALLOW ? LOG_WARNING : LOG_DEBUG),
+ "Hello permission check for uid=" UID_FMT " gid=" GID_FMT": %s",
+ uid, gid, strna(verdict_to_string(verdict)));
+
+ return verdict == ALLOW;
+}
+
+bool policy_check_recv(Policy *p,
+ uid_t uid,
+ gid_t gid,
+ int message_type,
+ const char *name,
+ const char *path,
+ const char *interface,
+ const char *member) {
+
+ struct policy_check_filter filter = {
+ .class = POLICY_ITEM_RECV,
+ .uid = uid,
+ .gid = gid,
+ .message_type = message_type,
+ .name = name,
+ .interface = interface,
+ .path = path,
+ .member = member,
+ };
+
+ int verdict;
+
+ assert(p);
+
+ verdict = policy_check(p, &filter);
+
+ log_full(LOG_AUTH | (verdict != ALLOW ? LOG_WARNING : LOG_DEBUG),
+ "Recieve permission check for uid=" UID_FMT " gid=" GID_FMT" message=%s name=%s interface=%s path=%s member=%s: %s",
+ uid, gid, bus_message_type_to_string(message_type), strna(name), strna(path), strna(interface), strna(member), strna(verdict_to_string(verdict)));
+
+ return verdict == ALLOW;
+}
+
+bool policy_check_send(Policy *p,
+ uid_t uid,
+ gid_t gid,
+ int message_type,
+ const char *name,
+ const char *path,
+ const char *interface,
+ const char *member) {
+
+ struct policy_check_filter filter = {
+ .class = POLICY_ITEM_SEND,
+ .uid = uid,
+ .gid = gid,
+ .message_type = message_type,
+ .name = name,
+ .interface = interface,
+ .path = path,
+ .member = member,
+ };
+
+ int verdict;
+
+ assert(p);
+
+ verdict = policy_check(p, &filter);
+
+ log_full(LOG_AUTH | (verdict != ALLOW ? LOG_WARNING : LOG_DEBUG),
+ "Send permission check for uid=" UID_FMT " gid=" GID_FMT" message=%s name=%s interface=%s path=%s member=%s: %s",
+ uid, gid, bus_message_type_to_string(message_type), strna(name), strna(path), strna(interface), strna(member), strna(verdict_to_string(verdict)));
- return false;
+ return verdict == ALLOW;
}
int policy_load(Policy *p, char **files) {
printf("%sGroup: %s (%d)\n",
prefix, strna(group), i->gid);
}
+ printf("%s-\n", prefix);
}
}
~ianmdlvl / elogind.git / blobdiff