TOMOYO: Add socket operation restriction support.

This patch adds support for permission checks for PF_INET/PF_INET6/PF_UNIX
socket's bind()/listen()/connect()/send() operations.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index 63720a3..d1c758e 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -23,6 +23,16 @@
 #include <linux/poll.h>
 #include <linux/binfmts.h>
 #include <linux/highmem.h>
+#include <linux/net.h>
+#include <linux/inet.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/un.h>
+#include <net/sock.h>
+#include <net/af_unix.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/udp.h>
 
 /********** Constants definitions. **********/
 
@@ -34,6 +44,12 @@
 #define TOMOYO_HASH_BITS  8
 #define TOMOYO_MAX_HASH (1u<<TOMOYO_HASH_BITS)
 
+/*
+ * TOMOYO checks only SOCK_STREAM, SOCK_DGRAM, SOCK_RAW, SOCK_SEQPACKET.
+ * Therefore, we don't need SOCK_MAX.
+ */
+#define TOMOYO_SOCK_MAX 6
+
 #define TOMOYO_EXEC_TMPSIZE     4096
 
 /* Profile number is an integer between 0 and 255. */
@@ -136,6 +152,7 @@
 /* Index numbers for entry type. */
 enum tomoyo_policy_id {
 	TOMOYO_ID_GROUP,
+	TOMOYO_ID_ADDRESS_GROUP,
 	TOMOYO_ID_PATH_GROUP,
 	TOMOYO_ID_NUMBER_GROUP,
 	TOMOYO_ID_TRANSITION_CONTROL,
@@ -166,6 +183,7 @@
 enum tomoyo_group_id {
 	TOMOYO_PATH_GROUP,
 	TOMOYO_NUMBER_GROUP,
+	TOMOYO_ADDRESS_GROUP,
 	TOMOYO_MAX_GROUP
 };
 
@@ -196,6 +214,8 @@
 	TOMOYO_TYPE_PATH_NUMBER_ACL,
 	TOMOYO_TYPE_MKDEV_ACL,
 	TOMOYO_TYPE_MOUNT_ACL,
+	TOMOYO_TYPE_INET_ACL,
+	TOMOYO_TYPE_UNIX_ACL,
 	TOMOYO_TYPE_ENV_ACL,
 };
 
@@ -229,6 +249,15 @@
 	TOMOYO_MAX_MKDEV_OPERATION
 };
 
+/* Index numbers for socket operations. */
+enum tomoyo_network_acl_index {
+	TOMOYO_NETWORK_BIND,    /* bind() operation. */
+	TOMOYO_NETWORK_LISTEN,  /* listen() operation. */
+	TOMOYO_NETWORK_CONNECT, /* connect() operation. */
+	TOMOYO_NETWORK_SEND,    /* send() operation. */
+	TOMOYO_MAX_NETWORK_OPERATION
+};
+
 /* Index numbers for access controls with two pathnames. */
 enum tomoyo_path2_acl_index {
 	TOMOYO_TYPE_LINK,
@@ -301,6 +330,21 @@
 	TOMOYO_MAC_FILE_MOUNT,
 	TOMOYO_MAC_FILE_UMOUNT,
 	TOMOYO_MAC_FILE_PIVOT_ROOT,
+	TOMOYO_MAC_NETWORK_INET_STREAM_BIND,
+	TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN,
+	TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT,
+	TOMOYO_MAC_NETWORK_INET_DGRAM_BIND,
+	TOMOYO_MAC_NETWORK_INET_DGRAM_SEND,
+	TOMOYO_MAC_NETWORK_INET_RAW_BIND,
+	TOMOYO_MAC_NETWORK_INET_RAW_SEND,
+	TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND,
+	TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN,
+	TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT,
+	TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND,
+	TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND,
+	TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND,
+	TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN,
+	TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT,
 	TOMOYO_MAC_ENVIRON,
 	TOMOYO_MAX_MAC_INDEX
 };
@@ -308,6 +352,7 @@
 /* Index numbers for category of functionality. */
 enum tomoyo_mac_category_index {
 	TOMOYO_MAC_CATEGORY_FILE,
+	TOMOYO_MAC_CATEGORY_NETWORK,
 	TOMOYO_MAC_CATEGORY_MISC,
 	TOMOYO_MAX_MAC_CATEGORY_INDEX
 };
@@ -403,6 +448,22 @@
 			const struct tomoyo_path_info *name;
 		} environ;
 		struct {
+			const __be32 *address;
+			u16 port;
+			/* One of values smaller than TOMOYO_SOCK_MAX. */
+			u8 protocol;
+			/* One of values in "enum tomoyo_network_acl_index". */
+			u8 operation;
+			bool is_ipv6;
+		} inet_network;
+		struct {
+			const struct tomoyo_path_info *address;
+			/* One of values smaller than TOMOYO_SOCK_MAX. */
+			u8 protocol;
+			/* One of values in "enum tomoyo_network_acl_index". */
+			u8 operation;
+		} unix_network;
+		struct {
 			const struct tomoyo_path_info *type;
 			const struct tomoyo_path_info *dir;
 			const struct tomoyo_path_info *dev;
@@ -448,7 +509,14 @@
 	u8 value_type[2];
 };
 
-/* Structure for "path_group"/"number_group" directive. */
+/* Structure for holding an IP address. */
+struct tomoyo_ipaddr_union {
+	struct in6_addr ip[2]; /* Big endian. */
+	struct tomoyo_group *group; /* Pointer to address group. */
+	bool is_ipv6; /* Valid only if @group == NULL. */
+};
+
+/* Structure for "path_group"/"number_group"/"address_group" directive. */
 struct tomoyo_group {
 	struct tomoyo_shared_acl_head head;
 	const struct tomoyo_path_info *group_name;
@@ -467,6 +535,13 @@
 	struct tomoyo_number_union number;
 };
 
+/* Structure for "address_group" directive. */
+struct tomoyo_address_group {
+	struct tomoyo_acl_head head;
+	/* Structure for holding an IP address. */
+	struct tomoyo_ipaddr_union address;
+};
+
 /* Subset of "struct stat". Used by conditional ACL and audit logs. */
 struct tomoyo_mini_stat {
 	uid_t uid;
@@ -650,6 +725,23 @@
 	const struct tomoyo_path_info *env; /* environment variable */
 };
 
+/* Structure for "network inet" directive. */
+struct tomoyo_inet_acl {
+	struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_INET_ACL */
+	u8 protocol;
+	u8 perm; /* Bitmask of values in "enum tomoyo_network_acl_index" */
+	struct tomoyo_ipaddr_union address;
+	struct tomoyo_number_union port;
+};
+
+/* Structure for "network unix" directive. */
+struct tomoyo_unix_acl {
+	struct tomoyo_acl_info head; /* type = TOMOYO_TYPE_UNIX_ACL */
+	u8 protocol;
+	u8 perm; /* Bitmask of values in "enum tomoyo_network_acl_index" */
+	struct tomoyo_name_union name;
+};
+
 /* Structure for holding a line from /sys/kernel/security/tomoyo/ interface. */
 struct tomoyo_acl_param {
 	char *data;
@@ -793,6 +885,8 @@
 
 /********** Function prototypes. **********/
 
+bool tomoyo_address_matches_group(const bool is_ipv6, const __be32 *address,
+				  const struct tomoyo_group *group);
 bool tomoyo_compare_number_union(const unsigned long value,
 				 const struct tomoyo_number_union *ptr);
 bool tomoyo_condition(struct tomoyo_request_info *r,
@@ -808,6 +902,8 @@
 bool tomoyo_number_matches_group(const unsigned long min,
 				 const unsigned long max,
 				 const struct tomoyo_group *group);
+bool tomoyo_parse_ipaddr_union(struct tomoyo_acl_param *param,
+			       struct tomoyo_ipaddr_union *ptr);
 bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
 			     struct tomoyo_name_union *ptr);
 bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
@@ -817,6 +913,7 @@
 bool tomoyo_permstr(const char *string, const char *keyword);
 bool tomoyo_str_starts(char **src, const char *find);
 char *tomoyo_encode(const char *str);
+char *tomoyo_encode2(const char *str, int str_len);
 char *tomoyo_init_log(struct tomoyo_request_info *r, int len, const char *fmt,
 		      va_list args);
 char *tomoyo_read_token(struct tomoyo_acl_param *param);
@@ -855,6 +952,13 @@
 			   const struct tomoyo_path_info *filename);
 int tomoyo_poll_control(struct file *file, poll_table *wait);
 int tomoyo_poll_log(struct file *file, poll_table *wait);
+int tomoyo_socket_bind_permission(struct socket *sock, struct sockaddr *addr,
+				  int addr_len);
+int tomoyo_socket_connect_permission(struct socket *sock,
+				     struct sockaddr *addr, int addr_len);
+int tomoyo_socket_listen_permission(struct socket *sock);
+int tomoyo_socket_sendmsg_permission(struct socket *sock, struct msghdr *msg,
+				     int size);
 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
 	__printf(2, 3);
 int tomoyo_update_domain(struct tomoyo_acl_info *new_entry, const int size,
@@ -874,8 +978,10 @@
 int tomoyo_write_file(struct tomoyo_acl_param *param);
 int tomoyo_write_group(struct tomoyo_acl_param *param, const u8 type);
 int tomoyo_write_misc(struct tomoyo_acl_param *param);
+int tomoyo_write_inet_network(struct tomoyo_acl_param *param);
 int tomoyo_write_transition_control(struct tomoyo_acl_param *param,
 				    const u8 type);
+int tomoyo_write_unix_network(struct tomoyo_acl_param *param);
 ssize_t tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
 			    const int buffer_len);
 ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
@@ -911,6 +1017,8 @@
 void tomoyo_memory_free(void *ptr);
 void tomoyo_normalize_line(unsigned char *buffer);
 void tomoyo_notify_gc(struct tomoyo_io_buffer *head, const bool is_register);
+void tomoyo_print_ip(char *buf, const unsigned int size,
+		     const struct tomoyo_ipaddr_union *ptr);
 void tomoyo_print_ulong(char *buffer, const int buffer_len,
 			const unsigned long value, const u8 type);
 void tomoyo_put_name_union(struct tomoyo_name_union *ptr);
@@ -933,6 +1041,8 @@
 					      + TOMOYO_MAX_MAC_CATEGORY_INDEX];
 extern const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE];
 extern const char * const tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION];
+extern const char * const tomoyo_proto_keyword[TOMOYO_SOCK_MAX];
+extern const char * const tomoyo_socket_keyword[TOMOYO_MAX_NETWORK_OPERATION];
 extern const u8 tomoyo_index2category[TOMOYO_MAX_MAC_INDEX];
 extern const u8 tomoyo_pn2mac[TOMOYO_MAX_PATH_NUMBER_OPERATION];
 extern const u8 tomoyo_pnnn2mac[TOMOYO_MAX_MKDEV_OPERATION];
@@ -1112,6 +1222,21 @@
 }
 
 /**
+ * tomoyo_same_ipaddr_union - Check for duplicated "struct tomoyo_ipaddr_union" entry.
+ *
+ * @a: Pointer to "struct tomoyo_ipaddr_union".
+ * @b: Pointer to "struct tomoyo_ipaddr_union".
+ *
+ * Returns true if @a == @b, false otherwise.
+ */
+static inline bool tomoyo_same_ipaddr_union
+(const struct tomoyo_ipaddr_union *a, const struct tomoyo_ipaddr_union *b)
+{
+	return !memcmp(a->ip, b->ip, sizeof(a->ip)) && a->group == b->group &&
+		a->is_ipv6 == b->is_ipv6;
+}
+
+/**
  * tomoyo_current_namespace - Get "struct tomoyo_policy_namespace" for current thread.
  *
  * Returns pointer to "struct tomoyo_policy_namespace" for current thread.