apparmor: add base infastructure for socket mediation

Provide a basic mediation of sockets. This is not a full net mediation
but just whether a spcific family of socket can be used by an
application, along with setting up some basic infrastructure for
network mediation to follow.

the user space rule hav the basic form of
  NETWORK RULE = [ QUALIFIERS ] 'network' [ DOMAIN ]
                 [ TYPE | PROTOCOL ]

  DOMAIN = ( 'inet' | 'ax25' | 'ipx' | 'appletalk' | 'netrom' |
             'bridge' | 'atmpvc' | 'x25' | 'inet6' | 'rose' |
	     'netbeui' | 'security' | 'key' | 'packet' | 'ash' |
	     'econet' | 'atmsvc' | 'sna' | 'irda' | 'pppox' |
	     'wanpipe' | 'bluetooth' | 'netlink' | 'unix' | 'rds' |
	     'llc' | 'can' | 'tipc' | 'iucv' | 'rxrpc' | 'isdn' |
	     'phonet' | 'ieee802154' | 'caif' | 'alg' | 'nfc' |
	     'vsock' | 'mpls' | 'ib' | 'kcm' ) ','

  TYPE = ( 'stream' | 'dgram' | 'seqpacket' |  'rdm' | 'raw' |
           'packet' )

  PROTOCOL = ( 'tcp' | 'udp' | 'icmp' )

eg.
  network,
  network inet,

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

4 files changed, 147 insertions, 11 deletions

diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h
index 620e81169659..ff4316e1068d 100644
--- a/security/apparmor/include/audit.h
+++ b/security/apparmor/include/audit.h
@@ -121,21 +121,29 @@ struct apparmor_audit_data {
 		/* these entries require a custom callback fn */
 		struct {
 			struct aa_label *peer;
-			struct {
-				const char *target;
-				kuid_t ouid;
-			} fs;
+			union {
+				struct {
+					kuid_t ouid;
+					const char *target;
+				} fs;
+				struct {
+					int type, protocol;
+					struct sock *peer_sk;
+					void *addr;
+					int addrlen;
+				} net;
+				int signal;
+				struct {
+					int rlim;
+					unsigned long max;
+				} rlim;
+			};
 		};
 		struct {
 			struct aa_profile *profile;
 			const char *ns;
 			long pos;
 		} iface;
-		int signal;
-		struct {
-			int rlim;
-			unsigned long max;
-		} rlim;
 		struct {
 			const char *src_name;
 			const char *type;
diff --git a/security/apparmor/include/net.h b/security/apparmor/include/net.h
new file mode 100644
index 000000000000..140c8efcf364
--- /dev/null
+++ b/security/apparmor/include/net.h
@@ -0,0 +1,114 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor network mediation definitions.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2017 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#ifndef __AA_NET_H
+#define __AA_NET_H
+
+#include <net/sock.h>
+#include <linux/path.h>
+
+#include "apparmorfs.h"
+#include "label.h"
+#include "perms.h"
+#include "policy.h"
+
+#define AA_MAY_SEND		AA_MAY_WRITE
+#define AA_MAY_RECEIVE		AA_MAY_READ
+
+#define AA_MAY_SHUTDOWN		AA_MAY_DELETE
+
+#define AA_MAY_CONNECT		AA_MAY_OPEN
+#define AA_MAY_ACCEPT		0x00100000
+
+#define AA_MAY_BIND		0x00200000
+#define AA_MAY_LISTEN		0x00400000
+
+#define AA_MAY_SETOPT		0x01000000
+#define AA_MAY_GETOPT		0x02000000
+
+#define NET_PERMS_MASK (AA_MAY_SEND | AA_MAY_RECEIVE | AA_MAY_CREATE |    \
+			AA_MAY_SHUTDOWN | AA_MAY_BIND | AA_MAY_LISTEN |	  \
+			AA_MAY_CONNECT | AA_MAY_ACCEPT | AA_MAY_SETATTR | \
+			AA_MAY_GETATTR | AA_MAY_SETOPT | AA_MAY_GETOPT)
+
+#define NET_FS_PERMS (AA_MAY_SEND | AA_MAY_RECEIVE | AA_MAY_CREATE |	\
+		      AA_MAY_SHUTDOWN | AA_MAY_CONNECT | AA_MAY_RENAME |\
+		      AA_MAY_SETATTR | AA_MAY_GETATTR | AA_MAY_CHMOD |	\
+		      AA_MAY_CHOWN | AA_MAY_CHGRP | AA_MAY_LOCK |	\
+		      AA_MAY_MPROT)
+
+#define NET_PEER_MASK (AA_MAY_SEND | AA_MAY_RECEIVE | AA_MAY_CONNECT |	\
+		       AA_MAY_ACCEPT)
+struct aa_sk_ctx {
+	struct aa_label *label;
+	struct aa_label *peer;
+	struct path path;
+};
+
+#define SK_CTX(X) ((X)->sk_security)
+#define SOCK_ctx(X) SOCK_INODE(X)->i_security
+#define DEFINE_AUDIT_NET(NAME, OP, SK, F, T, P)				  \
+	struct lsm_network_audit NAME ## _net = { .sk = (SK),		  \
+						  .family = (F)};	  \
+	DEFINE_AUDIT_DATA(NAME,						  \
+			  ((SK) && (F) != AF_UNIX) ? LSM_AUDIT_DATA_NET : \
+						     LSM_AUDIT_DATA_NONE, \
+			  OP);						  \
+	NAME.u.net = &(NAME ## _net);					  \
+	aad(&NAME)->net.type = (T);					  \
+	aad(&NAME)->net.protocol = (P)
+
+#define DEFINE_AUDIT_SK(NAME, OP, SK)					\
+	DEFINE_AUDIT_NET(NAME, OP, SK, (SK)->sk_family, (SK)->sk_type,	\
+			 (SK)->sk_protocol)
+
+/* struct aa_net - network confinement data
+ * @allow: basic network families permissions
+ * @audit: which network permissions to force audit
+ * @quiet: which network permissions to quiet rejects
+ */
+struct aa_net {
+	u16 allow[AF_MAX];
+	u16 audit[AF_MAX];
+	u16 quiet[AF_MAX];
+};
+
+
+extern struct aa_sfs_entry aa_sfs_entry_network[];
+
+void audit_net_cb(struct audit_buffer *ab, void *va);
+int aa_profile_af_perm(struct aa_profile *profile, struct common_audit_data *sa,
+		       u32 request, u16 family, int type);
+int aa_af_perm(struct aa_label *label, const char *op, u32 request, u16 family,
+	       int type, int protocol);
+static inline int aa_profile_af_sk_perm(struct aa_profile *profile,
+					struct common_audit_data *sa,
+					u32 request,
+					struct sock *sk)
+{
+	return aa_profile_af_perm(profile, sa, request, sk->sk_family,
+				  sk->sk_type);
+}
+int aa_sk_perm(const char *op, u32 request, struct sock *sk);
+
+int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
+		      struct socket *sock);
+
+
+static inline void aa_free_net_rules(struct aa_net *new)
+{
+	/* NOP */
+}
+
+#endif /* __AA_NET_H */
diff --git a/security/apparmor/include/perms.h b/security/apparmor/include/perms.h
index 2b27bb79aec4..af04d5a7d73d 100644
--- a/security/apparmor/include/perms.h
+++ b/security/apparmor/include/perms.h
@@ -135,9 +135,10 @@ extern struct aa_perms allperms;
 
 
 void aa_perm_mask_to_str(char *str, const char *chrs, u32 mask);
-void aa_audit_perm_names(struct audit_buffer *ab, const char **names, u32 mask);
+void aa_audit_perm_names(struct audit_buffer *ab, const char * const *names,
+			 u32 mask);
 void aa_audit_perm_mask(struct audit_buffer *ab, u32 mask, const char *chrs,
-			u32 chrsmask, const char **names, u32 namesmask);
+			u32 chrsmask, const char * const *names, u32 namesmask);
 void aa_apply_modes_to_perms(struct aa_profile *profile,
 			     struct aa_perms *perms);
 void aa_compute_perms(struct aa_dfa *dfa, unsigned int state,
diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h
index 17fe41a9cac3..4364088a0b9e 100644
--- a/security/apparmor/include/policy.h
+++ b/security/apparmor/include/policy.h
@@ -30,6 +30,7 @@
 #include "file.h"
 #include "lib.h"
 #include "label.h"
+#include "net.h"
 #include "perms.h"
 #include "resource.h"
 
@@ -111,6 +112,7 @@ struct aa_data {
  * @policy: general match rules governing policy
  * @file: The set of rules governing basic file access and domain transitions
  * @caps: capabilities for the profile
+ * @net: network controls for the profile
  * @rlimits: rlimits for the profile
  *
  * @dents: dentries for the profiles file entries in apparmorfs
@@ -148,6 +150,7 @@ struct aa_profile {
 	struct aa_policydb policy;
 	struct aa_file_rules file;
 	struct aa_caps caps;
+	struct aa_net net;
 	struct aa_rlimit rlimits;
 
 	struct aa_loaddata *rawdata;
@@ -220,6 +223,16 @@ static inline unsigned int PROFILE_MEDIATES_SAFE(struct aa_profile *profile,
 	return 0;
 }
 
+static inline unsigned int PROFILE_MEDIATES_AF(struct aa_profile *profile,
+					       u16 AF) {
+	unsigned int state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
+	u16 be_af = cpu_to_be16(AF);
+
+	if (!state)
+		return 0;
+	return aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
+}
+
 /**
  * aa_get_profile - increment refcount on profile @p
  * @p: profile  (MAYBE NULL)