#include "strv.h"
#include "conf-files.h"
#include "bus-internal.h"
+#include "bus-message.h"
#include "bus-policy.h"
static void policy_item_free(PolicyItem *i) {
DEFINE_TRIVIAL_CLEANUP_FUNC(PolicyItem*, policy_item_free);
+static void item_append(PolicyItem *i, PolicyItem **list) {
+
+ PolicyItem *tail;
+
+ LIST_FIND_TAIL(items, *list, tail);
+ LIST_INSERT_AFTER(items, *list, tail, i);
+}
+
static int file_load(Policy *p, const char *path) {
_cleanup_free_ char *c = NULL, *policy_user = NULL, *policy_group = NULL;
if (r == -EISDIR)
return r;
- log_error("Failed to load %s: %s", path, strerror(-r));
- return r;
+ return log_error_errno(r, "Failed to load %s: %m", path);
}
q = c;
int t;
t = xml_tokenize(&q, &name, &xml_state, &line);
- if (t < 0) {
- log_error("XML parse failure in %s: %s", path, strerror(-t));
- return t;
- }
+ if (t < 0)
+ return log_error_errno(t, "XML parse failure in %s: %m", path);
switch (state) {
else if (streq(name, "group"))
state = STATE_POLICY_GROUP;
else {
- log_warning("Attribute %s of <policy> tag unknown at %s:%u, ignoring.", name, path, line);
+ if (streq(name, "at_console"))
+ log_debug("Attribute %s of <policy> tag unsupported at %s:%u, ignoring.", name, path, line);
+ else
+ log_warning("Attribute %s of <policy> tag unknown at %s:%u, ignoring.", name, path, line);
state = STATE_POLICY_OTHER_ATTRIBUTE;
}
} else if (t == XML_TAG_CLOSE_EMPTY ||
ic = POLICY_ITEM_USER;
else if (streq(name, "group"))
ic = POLICY_ITEM_GROUP;
- else {
+ else if (streq(name, "eavesdrop")) {
+ log_debug("Unsupported attribute %s= at %s:%u, ignoring.", name, path, line);
+ i->class = POLICY_ITEM_IGNORE;
+ state = STATE_ALLOW_DENY_OTHER_ATTRIBUTE;
+ break;
+ } else {
log_error("Unknown attribute %s= at %s:%u, ignoring.", name, path, line);
state = STATE_ALLOW_DENY_OTHER_ATTRIBUTE;
break;
(streq(u, "sender") && ic == POLICY_ITEM_RECV))
state = STATE_ALLOW_DENY_NAME;
else {
- log_error("Unknown attribute %s= at %s:%u, ignoring.", name, path, line);
+ if (streq(u, "requested_reply"))
+ log_debug("Unsupported attribute %s= at %s:%u, ignoring.", name, path, line);
+ else
+ log_error("Unknown attribute %s= at %s:%u, ignoring.", name, path, line);
state = STATE_ALLOW_DENY_OTHER_ATTRIBUTE;
break;
}
}
if (policy_category == POLICY_CATEGORY_DEFAULT)
- LIST_PREPEND(items, p->default_items, i);
+ item_append(i, &p->default_items);
else if (policy_category == POLICY_CATEGORY_MANDATORY)
- LIST_PREPEND(items, p->default_items, i);
+ item_append(i, &p->mandatory_items);
else if (policy_category == POLICY_CATEGORY_USER) {
- PolicyItem *first;
+ const char *u = policy_user;
assert_cc(sizeof(uid_t) == sizeof(uint32_t));
- r = hashmap_ensure_allocated(&p->user_items, trivial_hash_func, trivial_compare_func);
+ r = hashmap_ensure_allocated(&p->user_items, NULL);
if (r < 0)
return log_oom();
- first = hashmap_get(p->user_items, UINT32_TO_PTR(i->uid));
- LIST_PREPEND(items, first, i);
+ if (!u) {
+ log_error("User policy without name");
+ return -EINVAL;
+ }
- r = hashmap_replace(p->user_items, UINT32_TO_PTR(i->uid), first);
+ r = get_user_creds(&u, &i->uid, NULL, NULL, NULL);
if (r < 0) {
- LIST_REMOVE(items, first, i);
- return log_oom();
+ log_error_errno(r, "Failed to resolve user %s, ignoring policy: %m", u);
+ free(i);
+ } else {
+ PolicyItem *first;
+
+ first = hashmap_get(p->user_items, UINT32_TO_PTR(i->uid));
+ item_append(i, &first);
+ i->uid_valid = true;
+
+ r = hashmap_replace(p->user_items, UINT32_TO_PTR(i->uid), first);
+ if (r < 0) {
+ LIST_REMOVE(items, first, i);
+ return log_oom();
+ }
}
+
} else if (policy_category == POLICY_CATEGORY_GROUP) {
- PolicyItem *first;
+ const char *g = policy_group;
assert_cc(sizeof(gid_t) == sizeof(uint32_t));
- r = hashmap_ensure_allocated(&p->group_items, trivial_hash_func, trivial_compare_func);
+ r = hashmap_ensure_allocated(&p->group_items, NULL);
if (r < 0)
return log_oom();
- first = hashmap_get(p->group_items, UINT32_TO_PTR(i->gid));
- LIST_PREPEND(items, first, i);
+ if (!g) {
+ log_error("Group policy without name");
+ return -EINVAL;
+ }
- r = hashmap_replace(p->group_items, UINT32_TO_PTR(i->gid), first);
+ r = get_group_creds(&g, &i->gid);
if (r < 0) {
- LIST_REMOVE(items, first, i);
- return log_oom();
+ log_error_errno(r, "Failed to resolve group %s, ignoring policy: %m", g);
+ free(i);
+ } else {
+ PolicyItem *first;
+
+ first = hashmap_get(p->group_items, UINT32_TO_PTR(i->gid));
+ item_append(i, &first);
+ i->gid_valid = true;
+
+ r = hashmap_replace(p->group_items, UINT32_TO_PTR(i->gid), first);
+ if (r < 0) {
+ LIST_REMOVE(items, first, i);
+ return log_oom();
+ }
}
}
return -EINVAL;
}
+ switch (i->class) {
+ case POLICY_ITEM_USER:
+ if (!streq(name, "*")) {
+ const char *u = name;
+
+ r = get_user_creds(&u, &i->uid, NULL, NULL, NULL);
+ if (r < 0)
+ log_error_errno(r, "Failed to resolve user %s: %m", name);
+ else
+ i->uid_valid = true;
+ }
+ break;
+ case POLICY_ITEM_GROUP:
+ if (!streq(name, "*")) {
+ const char *g = name;
+
+ r = get_group_creds(&g, &i->gid);
+ if (r < 0)
+ log_error_errno(r, "Failed to resolve group %s: %m", name);
+ else
+ i->gid_valid = true;
+ }
+ break;
+ default:
+ break;
+ }
+
i->name = name;
name = NULL;
+
state = STATE_ALLOW_DENY;
} else {
log_error("Unexpected token (14) in %s:%u.", path, line);
}
}
+enum {
+ DENY,
+ ALLOW,
+ DUNNO,
+};
+
+static const char *verdict_to_string(int v) {
+ switch (v) {
+
+ case DENY:
+ return "DENY";
+ case ALLOW:
+ return "ALLOW";
+ case DUNNO:
+ return "DUNNO";
+ }
+
+ return NULL;
+}
+
+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;
+};
+
+static int is_permissive(PolicyItem *i) {
+
+ assert(i);
+
+ return (i->type == POLICY_ITEM_ALLOW) ? ALLOW : DENY;
+}
+
+static int check_policy_item(PolicyItem *i, const struct policy_check_filter *filter) {
+
+ assert(i);
+ assert(filter);
+
+ switch (i->class) {
+ case POLICY_ITEM_SEND:
+ case POLICY_ITEM_RECV:
+
+ if (i->name && !streq_ptr(i->name, filter->name))
+ break;
+
+ if ((i->message_type != 0) && (i->message_type != filter->message_type))
+ break;
+
+ if (i->path && !streq_ptr(i->path, filter->path))
+ break;
+
+ if (i->member && !streq_ptr(i->member, filter->member))
+ break;
+
+ if (i->interface && !streq_ptr(i->interface, filter->interface))
+ break;
+
+ return is_permissive(i);
+
+ case POLICY_ITEM_OWN:
+ assert(filter->name);
+
+ if (streq(i->name, "*") || streq(i->name, filter->name))
+ return is_permissive(i);
+ break;
+
+ case POLICY_ITEM_OWN_PREFIX:
+ assert(filter->name);
+
+ if (streq(i->name, "*") || service_name_startswith(filter->name, i->name))
+ return is_permissive(i);
+ break;
+
+ case POLICY_ITEM_USER:
+ if (filter->uid != UID_INVALID)
+ if ((streq_ptr(i->name, "*") || (i->uid_valid && i->uid == filter->uid)))
+ return is_permissive(i);
+ break;
+
+ case POLICY_ITEM_GROUP:
+ if (filter->gid != GID_INVALID)
+ if ((streq_ptr(i->name, "*") || (i->gid_valid && i->gid == filter->gid)))
+ return is_permissive(i);
+ break;
+
+ case POLICY_ITEM_IGNORE:
+ default:
+ break;
+ }
+
+ return DUNNO;
+}
+
+static int check_policy_items(PolicyItem *items, const struct policy_check_filter *filter) {
+
+ PolicyItem *i;
+ 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) {
+ 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 verdict;
+}
+
+static int policy_check(Policy *p, const struct policy_check_filter *filter) {
+
+ PolicyItem *items;
+ 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 default items
+ * 2. Check group items
+ * 3. Check user items
+ * 4. Check mandatory items
+ *
+ * Later rules override earlier rules.
+ */
+
+ verdict = check_policy_items(p->default_items, filter);
+
+ if (filter->gid != GID_INVALID) {
+ items = hashmap_get(p->group_items, UINT32_TO_PTR(filter->gid));
+ if (items) {
+ v = check_policy_items(items, filter);
+ if (v != DUNNO)
+ verdict = v;
+ }
+ }
+
+ if (filter->uid != UID_INVALID) {
+ items = hashmap_get(p->user_items, UINT32_TO_PTR(filter->uid));
+ if (items) {
+ v = check_policy_items(items, filter);
+ if (v != DUNNO)
+ verdict = v;
+ }
+ }
+
+ 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 verdict == ALLOW;
+}
+
int policy_load(Policy *p, char **files) {
char **i;
int r;
char **j;
r = conf_files_list(&l, ".conf", NULL, *i, NULL);
- if (r < 0) {
- log_error("Failed to get configuration file list: %s", strerror(-r));
- return r;
- }
+ if (r < 0)
+ return log_error_errno(r, "Failed to get configuration file list: %m");
STRV_FOREACH(j, l)
file_load(p, *j);
p->user_items = p->group_items = NULL;
}
-static void dump_items(PolicyItem *i) {
+static void dump_items(PolicyItem *items, const char *prefix) {
+
+ PolicyItem *i;
- if (!i)
+ if (!items)
return;
- printf("Type: %s\n"
- "Class: %s\n",
- policy_item_type_to_string(i->type),
- policy_item_class_to_string(i->class));
+ if (!prefix)
+ prefix = "";
- if (i->interface)
- printf("Interface: %s\n",
- i->interface);
+ LIST_FOREACH(items, i, items) {
- if (i->member)
- printf("Member: %s\n",
- i->member);
+ printf("%sType: %s\n"
+ "%sClass: %s\n",
+ prefix, policy_item_type_to_string(i->type),
+ prefix, policy_item_class_to_string(i->class));
- if (i->error)
- printf("Error: %s\n",
- i->error);
+ if (i->interface)
+ printf("%sInterface: %s\n",
+ prefix, i->interface);
- if (i->path)
- printf("Path: %s\n",
- i->path);
+ if (i->member)
+ printf("%sMember: %s\n",
+ prefix, i->member);
- if (i->name)
- printf("Name: %s\n",
- i->name);
+ if (i->error)
+ printf("%sError: %s\n",
+ prefix, i->error);
- if (i->message_type != 0)
- printf("Message Type: %s\n",
- bus_message_type_to_string(i->message_type));
+ if (i->path)
+ printf("%sPath: %s\n",
+ prefix, i->path);
- if (i->uid_valid) {
- _cleanup_free_ char *user;
+ if (i->name)
+ printf("%sName: %s\n",
+ prefix, i->name);
- user = uid_to_name(i->uid);
+ if (i->message_type != 0)
+ printf("%sMessage Type: %s\n",
+ prefix, bus_message_type_to_string(i->message_type));
- printf("User: %s\n",
- strna(user));
- }
+ if (i->uid_valid) {
+ _cleanup_free_ char *user;
- if (i->gid_valid) {
- _cleanup_free_ char *group;
+ user = uid_to_name(i->uid);
- group = gid_to_name(i->gid);
+ printf("%sUser: %s (%d)\n",
+ prefix, strna(user), i->uid);
+ }
- printf("Group: %s\n",
- strna(group));
- }
+ if (i->gid_valid) {
+ _cleanup_free_ char *group;
- if (i->items_next) {
- printf("--\n");
- dump_items(i->items_next);
+ group = gid_to_name(i->gid);
+
+ printf("%sGroup: %s (%d)\n",
+ prefix, strna(group), i->gid);
+ }
+ printf("%s-\n", prefix);
}
}
void *k;
HASHMAP_FOREACH_KEY(i, k, h, j) {
- printf("Item for %u:\n", PTR_TO_UINT(k));
- dump_items(i);
+ printf("\t%s Item for %u:\n", draw_special_char(DRAW_ARROW), PTR_TO_UINT(k));
+ dump_items(i, "\t\t");
}
}
-noreturn void policy_dump(Policy *p) {
+void policy_dump(Policy *p) {
printf("%s Default Items:\n", draw_special_char(DRAW_ARROW));
- dump_items(p->default_items);
-
- printf("%s Mandatory Items:\n", draw_special_char(DRAW_ARROW));
- dump_items(p->mandatory_items);
+ dump_items(p->default_items, "\t");
printf("%s Group Items:\n", draw_special_char(DRAW_ARROW));
dump_hashmap_items(p->group_items);
printf("%s User Items:\n", draw_special_char(DRAW_ARROW));
dump_hashmap_items(p->user_items);
- exit(0);
+
+ printf("%s Mandatory Items:\n", draw_special_char(DRAW_ARROW));
+ dump_items(p->mandatory_items, "\t");
}
static const char* const policy_item_type_table[_POLICY_ITEM_TYPE_MAX] = {
[POLICY_ITEM_OWN_PREFIX] = "own-prefix",
[POLICY_ITEM_USER] = "user",
[POLICY_ITEM_GROUP] = "group",
+ [POLICY_ITEM_IGNORE] = "ignore",
};
DEFINE_STRING_TABLE_LOOKUP(policy_item_class, PolicyItemClass);