]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/commitdiff
UBUNTU: SAUCE: apparmor: af_unix mediation
authorJohn Johansen <john.johansen@canonical.com>
Wed, 19 Jul 2017 06:27:23 +0000 (23:27 -0700)
committerAndrea Righi <andrea.righi@canonical.com>
Mon, 15 Feb 2021 07:25:39 +0000 (08:25 +0100)
af_socket mediation did not make it into 4.17 so add remaining out
of tree patch

Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
security/apparmor/Makefile
security/apparmor/af_unix.c [new file with mode: 0644]
security/apparmor/apparmorfs.c
security/apparmor/file.c
security/apparmor/include/af_unix.h [new file with mode: 0644]
security/apparmor/include/net.h
security/apparmor/include/path.h
security/apparmor/include/policy.h
security/apparmor/lsm.c
security/apparmor/net.c

index ff23fcfefe196da8d7e09f18c9eb8a4c4a5c2c08..fad407f6f62c82527e256866392508edd635d6d0 100644 (file)
@@ -5,7 +5,8 @@ obj-$(CONFIG_SECURITY_APPARMOR) += apparmor.o
 
 apparmor-y := apparmorfs.o audit.o capability.o task.o ipc.o lib.o match.o \
               path.o domain.o policy.o policy_unpack.o procattr.o lsm.o \
-              resource.o secid.o file.o policy_ns.o label.o mount.o net.o
+              resource.o secid.o file.o policy_ns.o label.o mount.o net.o \
+              af_unix.o
 apparmor-$(CONFIG_SECURITY_APPARMOR_HASH) += crypto.o
 
 clean-files := capability_names.h rlim_names.h net_names.h
diff --git a/security/apparmor/af_unix.c b/security/apparmor/af_unix.c
new file mode 100644 (file)
index 0000000..54b3796
--- /dev/null
@@ -0,0 +1,652 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor af_unix fine grained mediation
+ *
+ * Copyright 2018 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.
+ */
+
+#include <net/tcp_states.h>
+
+#include "include/audit.h"
+#include "include/af_unix.h"
+#include "include/apparmor.h"
+#include "include/file.h"
+#include "include/label.h"
+#include "include/path.h"
+#include "include/policy.h"
+#include "include/cred.h"
+
+static inline struct sock *aa_sock(struct unix_sock *u)
+{
+       return &u->sk;
+}
+
+static inline int unix_fs_perm(const char *op, u32 mask, struct aa_label *label,
+                              struct unix_sock *u, int flags)
+{
+       AA_BUG(!label);
+       AA_BUG(!u);
+       AA_BUG(!UNIX_FS(aa_sock(u)));
+
+       if (unconfined(label) || !LABEL_MEDIATES(label, AA_CLASS_FILE))
+               return 0;
+
+       mask &= NET_FS_PERMS;
+       if (!u->path.dentry) {
+               struct path_cond cond = { };
+               struct aa_perms perms = { };
+               struct aa_profile *profile;
+
+               /* socket path has been cleared because it is being shutdown
+                * can only fall back to original sun_path request
+                */
+               struct aa_sk_ctx *ctx = SK_CTX(&u->sk);
+               if (ctx->path.dentry)
+                       return aa_path_perm(op, label, &ctx->path, flags, mask,
+                                           &cond);
+               return fn_for_each_confined(label, profile,
+                       ((flags | profile->path_flags) & PATH_MEDIATE_DELETED) ?
+                               __aa_path_perm(op, profile,
+                                              u->addr->name->sun_path, mask,
+                                              &cond, flags, &perms) :
+                               aa_audit_file(profile, &nullperms, op, mask,
+                                             u->addr->name->sun_path, NULL,
+                                             NULL, cond.uid,
+                                             "Failed name lookup - "
+                                             "deleted entry", -EACCES));
+       } else {
+               /* the sunpath may not be valid for this ns so use the path */
+               struct path_cond cond = { u->path.dentry->d_inode->i_uid,
+                                         u->path.dentry->d_inode->i_mode
+               };
+
+               return aa_path_perm(op, label, &u->path, flags, mask, &cond);
+       }
+
+       return 0;
+}
+
+/* passing in state returned by PROFILE_MEDIATES_AF */
+static unsigned int match_to_prot(struct aa_profile *profile,
+                                 unsigned int state, int type, int protocol,
+                                 const char **info)
+{
+       __be16 buffer[2];
+       buffer[0] = cpu_to_be16(type);
+       buffer[1] = cpu_to_be16(protocol);
+       state = aa_dfa_match_len(profile->policy.dfa, state, (char *) &buffer,
+                                4);
+       if (!state)
+               *info = "failed type and protocol match";
+       return state;
+}
+
+static unsigned int match_addr(struct aa_profile *profile, unsigned int state,
+                              struct sockaddr_un *addr, int addrlen)
+{
+       if (addr)
+               /* include leading \0 */
+               state = aa_dfa_match_len(profile->policy.dfa, state,
+                                        addr->sun_path,
+                                        unix_addr_len(addrlen));
+       else
+               /* anonymous end point */
+               state = aa_dfa_match_len(profile->policy.dfa, state, "\x01",
+                                        1);
+       /* todo change to out of band */
+       state = aa_dfa_null_transition(profile->policy.dfa, state);
+       return state;
+}
+
+static unsigned int match_to_local(struct aa_profile *profile,
+                                  unsigned int state, int type, int protocol,
+                                  struct sockaddr_un *addr, int addrlen,
+                                  const char **info)
+{
+       state = match_to_prot(profile, state, type, protocol, info);
+       if (state) {
+               state = match_addr(profile, state, addr, addrlen);
+               if (state) {
+                       /* todo: local label matching */
+                       state = aa_dfa_null_transition(profile->policy.dfa,
+                                                      state);
+                       if (!state)
+                               *info = "failed local label match";
+               } else
+                       *info = "failed local address match";
+       }
+
+       return state;
+}
+
+static unsigned int match_to_sk(struct aa_profile *profile,
+                               unsigned int state, struct unix_sock *u,
+                               const char **info)
+{
+       struct sockaddr_un *addr = NULL;
+       int addrlen = 0;
+
+       if (u->addr) {
+               addr = u->addr->name;
+               addrlen = u->addr->len;
+       }
+
+       return match_to_local(profile, state, u->sk.sk_type, u->sk.sk_protocol,
+                             addr, addrlen, info);
+}
+
+#define CMD_ADDR       1
+#define CMD_LISTEN     2
+#define CMD_OPT                4
+
+static inline unsigned int match_to_cmd(struct aa_profile *profile,
+                                       unsigned int state, struct unix_sock *u,
+                                       char cmd, const char **info)
+{
+       state = match_to_sk(profile, state, u, info);
+       if (state) {
+               state = aa_dfa_match_len(profile->policy.dfa, state, &cmd, 1);
+               if (!state)
+                       *info = "failed cmd selection match";
+       }
+
+       return state;
+}
+
+static inline unsigned int match_to_peer(struct aa_profile *profile,
+                                        unsigned int state,
+                                        struct unix_sock *u,
+                                        struct sockaddr_un *peer_addr,
+                                        int peer_addrlen,
+                                        const char **info)
+{
+       state = match_to_cmd(profile, state, u, CMD_ADDR, info);
+       if (state) {
+               state = match_addr(profile, state, peer_addr, peer_addrlen);
+               if (!state)
+                       *info = "failed peer address match";
+       }
+       return state;
+}
+
+static int do_perms(struct aa_profile *profile, unsigned int state, u32 request,
+                   struct common_audit_data *sa)
+{
+       struct aa_perms perms;
+
+       AA_BUG(!profile);
+
+       aa_compute_perms(profile->policy.dfa, state, &perms);
+       aa_apply_modes_to_perms(profile, &perms);
+       return aa_check_perms(profile, &perms, request, sa,
+                             audit_net_cb);
+}
+
+static int match_label(struct aa_profile *profile, struct aa_profile *peer,
+                             unsigned int state, u32 request,
+                             struct common_audit_data *sa)
+{
+       AA_BUG(!profile);
+       AA_BUG(!peer);
+
+       aad(sa)->peer = &peer->label;
+
+       if (state) {
+               state = aa_dfa_match(profile->policy.dfa, state,
+                                    peer->base.hname);
+               if (!state)
+                       aad(sa)->info = "failed peer label match";
+       }
+       return do_perms(profile, state, request, sa);
+}
+
+
+/* unix sock creation comes before we know if the socket will be an fs
+ * socket
+ * v6 - semantics are handled by mapping in profile load
+ * v7 - semantics require sock create for tasks creating an fs socket.
+ */
+static int profile_create_perm(struct aa_profile *profile, int family,
+                              int type, int protocol)
+{
+       unsigned int state;
+       DEFINE_AUDIT_NET(sa, OP_CREATE, NULL, family, type, protocol);
+
+       AA_BUG(!profile);
+       AA_BUG(profile_unconfined(profile));
+
+       if ((state = PROFILE_MEDIATES_AF(profile, AF_UNIX))) {
+               state = match_to_prot(profile, state, type, protocol,
+                                     &aad(&sa)->info);
+               return do_perms(profile, state, AA_MAY_CREATE, &sa);
+       }
+
+       return aa_profile_af_perm(profile, &sa, AA_MAY_CREATE, family, type);
+}
+
+int aa_unix_create_perm(struct aa_label *label, int family, int type,
+                       int protocol)
+{
+       struct aa_profile *profile;
+
+       if (unconfined(label))
+               return 0;
+
+       return fn_for_each_confined(label, profile,
+                       profile_create_perm(profile, family, type, protocol));
+}
+
+
+static inline int profile_sk_perm(struct aa_profile *profile, const char *op,
+                                 u32 request, struct sock *sk)
+{
+       unsigned int state;
+       DEFINE_AUDIT_SK(sa, op, sk);
+
+       AA_BUG(!profile);
+       AA_BUG(!sk);
+       AA_BUG(UNIX_FS(sk));
+       AA_BUG(profile_unconfined(profile));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               state = match_to_sk(profile, state, unix_sk(sk),
+                                   &aad(&sa)->info);
+               return do_perms(profile, state, request, &sa);
+       }
+
+       return aa_profile_af_sk_perm(profile, &sa, request, sk);
+}
+
+int aa_unix_label_sk_perm(struct aa_label *label, const char *op, u32 request,
+                         struct sock *sk)
+{
+       struct aa_profile *profile;
+
+       return fn_for_each_confined(label, profile,
+                       profile_sk_perm(profile, op, request, sk));
+}
+
+static int unix_label_sock_perm(struct aa_label *label, const char *op, u32 request,
+                               struct socket *sock)
+{
+       if (unconfined(label))
+               return 0;
+       if (UNIX_FS(sock->sk))
+               return unix_fs_perm(op, request, label, unix_sk(sock->sk), 0);
+
+       return aa_unix_label_sk_perm(label, op, request, sock->sk);
+}
+
+/* revaliation, get/set attr */
+int aa_unix_sock_perm(const char *op, u32 request, struct socket *sock)
+{
+       struct aa_label *label;
+       int error;
+
+       label = begin_current_label_crit_section();
+       error = unix_label_sock_perm(label, op, request, sock);
+       end_current_label_crit_section(label);
+
+       return error;
+}
+
+static int profile_bind_perm(struct aa_profile *profile, struct sock *sk,
+                            struct sockaddr *addr, int addrlen)
+{
+       unsigned int state;
+       DEFINE_AUDIT_SK(sa, OP_BIND, sk);
+
+       AA_BUG(!profile);
+       AA_BUG(!sk);
+       AA_BUG(addr->sa_family != AF_UNIX);
+       AA_BUG(profile_unconfined(profile));
+       AA_BUG(unix_addr_fs(addr, addrlen));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               /* bind for abstract socket */
+               aad(&sa)->net.addr = unix_addr(addr);
+               aad(&sa)->net.addrlen = addrlen;
+
+               state = match_to_local(profile, state,
+                                      sk->sk_type, sk->sk_protocol,
+                                      unix_addr(addr), addrlen,
+                                      &aad(&sa)->info);
+               return do_perms(profile, state, AA_MAY_BIND, &sa);
+       }
+
+       return aa_profile_af_sk_perm(profile, &sa, AA_MAY_BIND, sk);
+}
+
+int aa_unix_bind_perm(struct socket *sock, struct sockaddr *address,
+                     int addrlen)
+{
+       struct aa_profile *profile;
+       struct aa_label *label;
+       int error = 0;
+
+        label = begin_current_label_crit_section();
+        /* fs bind is handled by mknod */
+       if (!(unconfined(label) || unix_addr_fs(address, addrlen)))
+               error = fn_for_each_confined(label, profile,
+                               profile_bind_perm(profile, sock->sk, address,
+                                                 addrlen));
+       end_current_label_crit_section(label);
+
+       return error;
+}
+
+int aa_unix_connect_perm(struct socket *sock, struct sockaddr *address,
+                        int addrlen)
+{
+       /* unix connections are covered by the
+        * - unix_stream_connect (stream) and unix_may_send hooks (dgram)
+        * - fs connect is handled by open
+        */
+       return 0;
+}
+
+static int profile_listen_perm(struct aa_profile *profile, struct sock *sk,
+                              int backlog)
+{
+       unsigned int state;
+       DEFINE_AUDIT_SK(sa, OP_LISTEN, sk);
+
+       AA_BUG(!profile);
+       AA_BUG(!sk);
+       AA_BUG(UNIX_FS(sk));
+       AA_BUG(profile_unconfined(profile));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               __be16 b = cpu_to_be16(backlog);
+
+               state = match_to_cmd(profile, state, unix_sk(sk), CMD_LISTEN,
+                                    &aad(&sa)->info);
+               if (state) {
+                       state = aa_dfa_match_len(profile->policy.dfa, state,
+                                                (char *) &b, 2);
+                       if (!state)
+                               aad(&sa)->info = "failed listen backlog match";
+               }
+               return do_perms(profile, state, AA_MAY_LISTEN, &sa);
+       }
+
+       return aa_profile_af_sk_perm(profile, &sa, AA_MAY_LISTEN, sk);
+}
+
+int aa_unix_listen_perm(struct socket *sock, int backlog)
+{
+       struct aa_profile *profile;
+       struct aa_label *label;
+       int error = 0;
+
+       label = begin_current_label_crit_section();
+       if (!(unconfined(label) || UNIX_FS(sock->sk)))
+               error = fn_for_each_confined(label, profile,
+                               profile_listen_perm(profile, sock->sk,
+                                                   backlog));
+       end_current_label_crit_section(label);
+
+       return error;
+}
+
+
+static inline int profile_accept_perm(struct aa_profile *profile,
+                                     struct sock *sk,
+                                     struct sock *newsk)
+{
+       unsigned int state;
+       DEFINE_AUDIT_SK(sa, OP_ACCEPT, sk);
+
+       AA_BUG(!profile);
+       AA_BUG(!sk);
+       AA_BUG(UNIX_FS(sk));
+       AA_BUG(profile_unconfined(profile));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               state = match_to_sk(profile, state, unix_sk(sk),
+                                   &aad(&sa)->info);
+               return do_perms(profile, state, AA_MAY_ACCEPT, &sa);
+       }
+
+       return aa_profile_af_sk_perm(profile, &sa, AA_MAY_ACCEPT, sk);
+}
+
+/* ability of sock to connect, not peer address binding */
+int aa_unix_accept_perm(struct socket *sock, struct socket *newsock)
+{
+       struct aa_profile *profile;
+       struct aa_label *label;
+       int error = 0;
+
+       label = begin_current_label_crit_section();
+       if (!(unconfined(label) || UNIX_FS(sock->sk)))
+               error = fn_for_each_confined(label, profile,
+                               profile_accept_perm(profile, sock->sk,
+                                                   newsock->sk));
+       end_current_label_crit_section(label);
+
+       return error;
+}
+
+
+/* dgram handled by unix_may_sendmsg, right to send on stream done at connect
+ * could do per msg unix_stream here
+ */
+/* sendmsg, recvmsg */
+int aa_unix_msg_perm(const char *op, u32 request, struct socket *sock,
+                    struct msghdr *msg, int size)
+{
+       return 0;
+}
+
+
+static int profile_opt_perm(struct aa_profile *profile, const char *op, u32 request,
+                           struct sock *sk, int level, int optname)
+{
+       unsigned int state;
+       DEFINE_AUDIT_SK(sa, op, sk);
+
+       AA_BUG(!profile);
+       AA_BUG(!sk);
+       AA_BUG(UNIX_FS(sk));
+       AA_BUG(profile_unconfined(profile));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               __be16 b = cpu_to_be16(optname);
+
+               state = match_to_cmd(profile, state, unix_sk(sk), CMD_OPT,
+                                    &aad(&sa)->info);
+               if (state) {
+                       state = aa_dfa_match_len(profile->policy.dfa, state,
+                                                (char *) &b, 2);
+                       if (!state)
+                               aad(&sa)->info = "failed sockopt match";
+               }
+               return do_perms(profile, state, request, &sa);
+       }
+
+       return aa_profile_af_sk_perm(profile, &sa, request, sk);
+}
+
+int aa_unix_opt_perm(const char *op, u32 request, struct socket *sock, int level,
+                    int optname)
+{
+       struct aa_profile *profile;
+       struct aa_label *label;
+       int error = 0;
+
+       label = begin_current_label_crit_section();
+       if (!(unconfined(label) || UNIX_FS(sock->sk)))
+               error = fn_for_each_confined(label, profile,
+                               profile_opt_perm(profile, op, request,
+                                                sock->sk, level, optname));
+       end_current_label_crit_section(label);
+
+       return error;
+}
+
+/* null peer_label is allowed, in which case the peer_sk label is used */
+static int profile_peer_perm(struct aa_profile *profile, const char *op, u32 request,
+                            struct sock *sk, struct sock *peer_sk,
+                            struct aa_label *peer_label,
+                            struct common_audit_data *sa)
+{
+       unsigned int state;
+
+       AA_BUG(!profile);
+       AA_BUG(profile_unconfined(profile));
+       AA_BUG(!sk);
+       AA_BUG(!peer_sk);
+       AA_BUG(UNIX_FS(peer_sk));
+
+       state = PROFILE_MEDIATES_AF(profile, AF_UNIX);
+       if (state) {
+               struct aa_sk_ctx *peer_ctx = SK_CTX(peer_sk);
+               struct aa_profile *peerp;
+               struct sockaddr_un *addr = NULL;
+               int len = 0;
+               if (unix_sk(peer_sk)->addr) {
+                       addr = unix_sk(peer_sk)->addr->name;
+                       len = unix_sk(peer_sk)->addr->len;
+               }
+               state = match_to_peer(profile, state, unix_sk(sk),
+                                     addr, len, &aad(sa)->info);
+               if (!peer_label)
+                       peer_label = peer_ctx->label;
+               return fn_for_each_in_ns(peer_label, peerp,
+                                  match_label(profile, peerp, state, request,
+                                              sa));
+       }
+
+       return aa_profile_af_sk_perm(profile, sa, request, sk);
+}
+
+/**
+ *
+ * Requires: lock held on both @sk and @peer_sk
+ */
+int aa_unix_peer_perm(struct aa_label *label, const char *op, u32 request,
+                     struct sock *sk, struct sock *peer_sk,
+                     struct aa_label *peer_label)
+{
+       struct unix_sock *peeru = unix_sk(peer_sk);
+       struct unix_sock *u = unix_sk(sk);
+
+       AA_BUG(!label);
+       AA_BUG(!sk);
+       AA_BUG(!peer_sk);
+
+       if (UNIX_FS(aa_sock(peeru)))
+               return unix_fs_perm(op, request, label, peeru, 0);
+       else if (UNIX_FS(aa_sock(u)))
+               return unix_fs_perm(op, request, label, u, 0);
+       else {
+               struct aa_profile *profile;
+               DEFINE_AUDIT_SK(sa, op, sk);
+               aad(&sa)->net.peer_sk = peer_sk;
+
+               /* TODO: ns!!! */
+               if (!net_eq(sock_net(sk), sock_net(peer_sk))) {
+                       ;
+               }
+
+               if (unconfined(label))
+                       return 0;
+
+               return fn_for_each_confined(label, profile,
+                               profile_peer_perm(profile, op, request, sk,
+                                                 peer_sk, peer_label, &sa));
+       }
+}
+
+
+/* from net/unix/af_unix.c */
+static void unix_state_double_lock(struct sock *sk1, struct sock *sk2)
+{
+       if (unlikely(sk1 == sk2) || !sk2) {
+               unix_state_lock(sk1);
+               return;
+       }
+       if (sk1 < sk2) {
+               unix_state_lock(sk1);
+               unix_state_lock_nested(sk2);
+       } else {
+               unix_state_lock(sk2);
+               unix_state_lock_nested(sk1);
+       }
+}
+
+static void unix_state_double_unlock(struct sock *sk1, struct sock *sk2)
+{
+       if (unlikely(sk1 == sk2) || !sk2) {
+               unix_state_unlock(sk1);
+               return;
+       }
+       unix_state_unlock(sk1);
+       unix_state_unlock(sk2);
+}
+
+int aa_unix_file_perm(struct aa_label *label, const char *op, u32 request,
+                     struct socket *sock)
+{
+       struct sock *peer_sk = NULL;
+       u32 sk_req = request & ~NET_PEER_MASK;
+       int error = 0;
+
+       AA_BUG(!label);
+       AA_BUG(!sock);
+       AA_BUG(!sock->sk);
+       AA_BUG(sock->sk->sk_family != AF_UNIX);
+
+       /* TODO: update sock label with new task label */
+       unix_state_lock(sock->sk);
+       peer_sk = unix_peer(sock->sk);
+       if (peer_sk)
+               sock_hold(peer_sk);
+       if (!unix_connected(sock) && sk_req) {
+               error = unix_label_sock_perm(label, op, sk_req, sock);
+               if (!error) {
+                       // update label
+               }
+       }
+       unix_state_unlock(sock->sk);
+       if (!peer_sk)
+               return error;
+
+       unix_state_double_lock(sock->sk, peer_sk);
+       if (UNIX_FS(sock->sk)) {
+               error = unix_fs_perm(op, request, label, unix_sk(sock->sk),
+                                    PATH_SOCK_COND);
+       } else if (UNIX_FS(peer_sk)) {
+               error = unix_fs_perm(op, request, label, unix_sk(peer_sk),
+                                    PATH_SOCK_COND);
+       } else {
+               struct aa_sk_ctx *pctx = SK_CTX(peer_sk);
+               if (sk_req)
+                       error = aa_unix_label_sk_perm(label, op, sk_req,
+                                                     sock->sk);
+               last_error(error,
+                       xcheck(aa_unix_peer_perm(label, op,
+                                                MAY_READ | MAY_WRITE,
+                                                sock->sk, peer_sk, NULL),
+                              aa_unix_peer_perm(pctx->label, op,
+                                                MAY_READ | MAY_WRITE,
+                                                peer_sk, sock->sk, label)));
+       }
+
+       unix_state_double_unlock(sock->sk, peer_sk);
+       sock_put(peer_sk);
+
+       return error;
+}
index 0806140f203e22a0a6dddc28761d2a3a0825f224..ee54211393798b56574b6f36381c6dc0beb30da9 100644 (file)
@@ -2345,6 +2345,11 @@ static struct aa_sfs_entry aa_sfs_entry_ns[] = {
        { }
 };
 
+static struct aa_sfs_entry aa_sfs_entry_dbus[] = {
+       AA_SFS_FILE_STRING("mask", "acquire send receive"),
+       { }
+};
+
 static struct aa_sfs_entry aa_sfs_entry_query_label[] = {
        AA_SFS_FILE_STRING("perms", "allow deny audit quiet"),
        AA_SFS_FILE_BOOLEAN("data",             1),
@@ -2369,6 +2374,7 @@ static struct aa_sfs_entry aa_sfs_entry_features[] = {
        AA_SFS_DIR("caps",                      aa_sfs_entry_caps),
        AA_SFS_DIR("ptrace",                    aa_sfs_entry_ptrace),
        AA_SFS_DIR("signal",                    aa_sfs_entry_signal),
+       AA_SFS_DIR("dbus",                      aa_sfs_entry_dbus),
        AA_SFS_DIR("query",                     aa_sfs_entry_query),
        { }
 };
index 92acf9a49405c4cbc23132e90b738f2c6bd43681..60cd84cfc6707be1561502723d1e0d3b5d21d76a 100644 (file)
@@ -12,6 +12,7 @@
 #include <linux/fdtable.h>
 #include <linux/file.h>
 
+#include "include/af_unix.h"
 #include "include/apparmor.h"
 #include "include/audit.h"
 #include "include/cred.h"
@@ -269,7 +270,8 @@ int __aa_path_perm(const char *op, struct aa_profile *profile, const char *name,
 {
        int e = 0;
 
-       if (profile_unconfined(profile))
+       if (profile_unconfined(profile) ||
+           ((flags & PATH_SOCK_COND) && !PROFILE_MEDIATES_AF(profile, AF_UNIX)))
                return 0;
        aa_str_perms(profile->file.dfa, profile->file.start, name, cond, perms);
        if (request & ~perms->allow)
diff --git a/security/apparmor/include/af_unix.h b/security/apparmor/include/af_unix.h
new file mode 100644 (file)
index 0000000..d1b7f23
--- /dev/null
@@ -0,0 +1,114 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor af_unix fine grained mediation
+ *
+ * Copyright 2014 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_AF_UNIX_H
+
+#include <net/af_unix.h>
+
+#include "label.h"
+//#include "include/net.h"
+
+#define unix_addr_len(L) ((L) - sizeof(sa_family_t))
+#define unix_abstract_name_len(L) (unix_addr_len(L) - 1)
+#define unix_abstract_len(U) (unix_abstract_name_len((U)->addr->len))
+#define addr_unix_abstract_name(B) ((B)[0] == 0)
+#define addr_unix_anonymous(U) (addr_unix_len(U) <= 0)
+#define addr_unix_abstract(U) (!addr_unix_anonymous(U) && addr_unix_abstract_name((U)->addr))
+//#define unix_addr_fs(U) (!unix_addr_anonymous(U) && !unix_addr_abstract_name((U)->addr))
+
+#define unix_addr(A) ((struct sockaddr_un *)(A))
+#define unix_addr_anon(A, L) ((A) && unix_addr_len(L) <= 0)
+#define unix_addr_fs(A, L) (!unix_addr_anon(A, L) && !addr_unix_abstract_name(unix_addr(A)->sun_path))
+
+#define UNIX_ANONYMOUS(U) (!unix_sk(U)->addr)
+/* from net/unix/af_unix.c */
+#define UNIX_ABSTRACT(U) (!UNIX_ANONYMOUS(U) &&                                \
+                         unix_sk(U)->addr->hash < UNIX_HASH_SIZE)
+#define UNIX_FS(U) (!UNIX_ANONYMOUS(U) && unix_sk(U)->addr->name->sun_path[0])
+#define unix_peer(sk) (unix_sk(sk)->peer)
+#define unix_connected(S) ((S)->state == SS_CONNECTED)
+
+static inline void print_unix_addr(struct sockaddr_un *A, int L)
+{
+       char *buf = (A) ? (char *) &(A)->sun_path : NULL;
+       int len = unix_addr_len(L);
+       if (!buf || len <= 0)
+               printk(" <anonymous>");
+       else if (buf[0])
+               printk(" %s", buf);
+       else
+               /* abstract name len includes leading \0 */
+               printk(" %d @%.*s", len - 1, len - 1, buf+1);
+};
+
+/*
+       printk("%s: %s: f %d, t %d, p %d", __FUNCTION__,                \
+              #SK ,                                                    \
+*/
+#define print_unix_sk(SK)                                              \
+do {                                                                   \
+       struct unix_sock *u = unix_sk(SK);                              \
+       printk("%s: f %d, t %d, p %d",  #SK ,                           \
+              (SK)->sk_family, (SK)->sk_type, (SK)->sk_protocol);      \
+       if (u->addr)                                                    \
+               print_unix_addr(u->addr->name, u->addr->len);           \
+       else                                                            \
+               print_unix_addr(NULL, sizeof(sa_family_t));             \
+       /* printk("\n");*/                                              \
+} while (0)
+
+#define print_sk(SK)                                                   \
+do {                                                                   \
+       if (!(SK)) {                                                    \
+               printk("%s: %s is null\n", __FUNCTION__, #SK);          \
+       } else if ((SK)->sk_family == PF_UNIX) {                        \
+               print_unix_sk(SK);                                      \
+               printk("\n");                                           \
+       } else {                                                        \
+               printk("%s: %s: family %d\n", __FUNCTION__, #SK ,       \
+                      (SK)->sk_family);                                \
+       }                                                               \
+} while (0)
+
+#define print_sock_addr(U) \
+do {                          \
+       printk("%s:\n", __FUNCTION__);                                  \
+       printk("    sock %s:", sock_ctx && sock_ctx->label ? aa_label_printk(sock_ctx->label, GFP_ATOMIC); : "<null>"); print_sk(sock); \
+       printk("    other %s:", other_ctx && other_ctx->label ? aa_label_printk(other_ctx->label, GFP_ATOMIC); : "<null>"); print_sk(other); \
+       printk("    new %s", new_ctx && new_ctx->label ? aa_label_printk(new_ctx->label, GFP_ATOMIC); : "<null>"); print_sk(newsk); \
+} while (0)
+
+
+
+
+int aa_unix_peer_perm(struct aa_label *label, const char *op, u32 request,
+                     struct sock *sk, struct sock *peer_sk,
+                     struct aa_label *peer_label);
+int aa_unix_label_sk_perm(struct aa_label *label, const char *op, u32 request,
+                         struct sock *sk);
+int aa_unix_sock_perm(const char *op, u32 request, struct socket *sock);
+int aa_unix_create_perm(struct aa_label *label, int family, int type,
+                       int protocol);
+int aa_unix_bind_perm(struct socket *sock, struct sockaddr *address,
+                     int addrlen);
+int aa_unix_connect_perm(struct socket *sock, struct sockaddr *address,
+                        int addrlen);
+int aa_unix_listen_perm(struct socket *sock, int backlog);
+int aa_unix_accept_perm(struct socket *sock, struct socket *newsock);
+int aa_unix_msg_perm(const char *op, u32 request, struct socket *sock,
+                    struct msghdr *msg, int size);
+int aa_unix_opt_perm(const char *op, u32 request, struct socket *sock, int level,
+                    int optname);
+int aa_unix_file_perm(struct aa_label *label, const char *op, u32 request,
+                     struct socket *sock);
+
+#endif /* __AA_AF_UNIX_H */
index 98a42efb9d700bcbf2f1895f46c28efce674384e..b4044facd8114afd9b19f24aa9040e6582a8d82c 100644 (file)
@@ -49,6 +49,7 @@
 struct aa_sk_ctx {
        struct aa_label *label;
        struct aa_label *peer;
+       struct path path;
 };
 
 #define SK_CTX(X) ((X)->sk_security)
@@ -83,6 +84,9 @@ struct aa_net_compat {
 ({                                             \
        int __e;                                \
        switch ((FAMILY)) {                     \
+       case AF_UNIX:                           \
+               __e = aa_unix_ ## FN;           \
+               break;                          \
        default:                                \
                __e = DEF_FN;                   \
        }                                       \
index 44a7945fbe3c6575100e5bf03d14e5abace7c2f4..44592cd989d733e6a2ae703adf21cfd1d390ee47 100644 (file)
@@ -13,6 +13,7 @@
 
 enum path_flags {
        PATH_IS_DIR = 0x1,              /* path is a directory */
+       PATH_SOCK_COND = 0x2,
        PATH_CONNECT_PATH = 0x4,        /* connect disconnected paths to / */
        PATH_CHROOT_REL = 0x8,          /* do path lookup relative to chroot */
        PATH_CHROOT_NSCONNECT = 0x10,   /* connect paths that are at ns root */
index f904105f48de54fe64aefbe01706d3de80a7eccf..f1c9cdc49a0dc0bfb167cc6d80133faa807d0496 100644 (file)
@@ -230,9 +230,13 @@ static inline unsigned int PROFILE_MEDIATES_AF(struct aa_profile *profile,
        unsigned int state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
        __be16 be_af = cpu_to_be16(AF);
 
-       if (!state)
-               return 0;
-       return aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
+       if (!state) {
+               state = PROFILE_MEDIATES(profile, AA_CLASS_NET_COMPAT);
+               if (!state)
+                       return 0;
+       }
+       state = aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
+       return state;
 }
 
 /**
index 1b0aba8eb7235f129b260ae36f6ba1ab2c2317ca..de7de8780b13eb3cea3c615097c55debbeeae6ce 100644 (file)
@@ -25,6 +25,7 @@
 #include <net/sock.h>
 #include <uapi/linux/mount.h>
 
+#include "include/af_unix.h"
 #include "include/apparmor.h"
 #include "include/apparmorfs.h"
 #include "include/audit.h"
@@ -792,6 +793,7 @@ static void apparmor_sk_free_security(struct sock *sk)
        SK_CTX(sk) = NULL;
        aa_put_label(ctx->label);
        aa_put_label(ctx->peer);
+       path_put(&ctx->path);
        kfree(ctx);
 }
 
@@ -811,6 +813,99 @@ static void apparmor_sk_clone_security(const struct sock *sk,
        if (new->peer)
                aa_put_label(new->peer);
        new->peer = aa_get_label(ctx->peer);
+       new->path = ctx->path;
+       path_get(&new->path);
+}
+
+static struct path *UNIX_FS_CONN_PATH(struct sock *sk, struct sock *newsk)
+{
+       if (sk->sk_family == PF_UNIX && UNIX_FS(sk))
+               return &unix_sk(sk)->path;
+       else if (newsk->sk_family == PF_UNIX && UNIX_FS(newsk))
+               return &unix_sk(newsk)->path;
+       return NULL;
+}
+
+/**
+ * apparmor_unix_stream_connect - check perms before making unix domain conn
+ *
+ * peer is locked when this hook is called
+ */
+static int apparmor_unix_stream_connect(struct sock *sk, struct sock *peer_sk,
+                                       struct sock *newsk)
+{
+       struct aa_sk_ctx *sk_ctx = SK_CTX(sk);
+       struct aa_sk_ctx *peer_ctx = SK_CTX(peer_sk);
+       struct aa_sk_ctx *new_ctx = SK_CTX(newsk);
+       struct aa_label *label;
+       struct path *path;
+       int error;
+
+       label = __begin_current_label_crit_section();
+       error = aa_unix_peer_perm(label, OP_CONNECT,
+                               (AA_MAY_CONNECT | AA_MAY_SEND | AA_MAY_RECEIVE),
+                                 sk, peer_sk, NULL);
+       if (!UNIX_FS(peer_sk)) {
+               last_error(error,
+                       aa_unix_peer_perm(peer_ctx->label, OP_CONNECT,
+                               (AA_MAY_ACCEPT | AA_MAY_SEND | AA_MAY_RECEIVE),
+                               peer_sk, sk, label));
+       }
+       __end_current_label_crit_section(label);
+
+       if (error)
+               return error;
+
+       /* label newsk if it wasn't labeled in post_create. Normally this
+        * would be done in sock_graft, but because we are directly looking
+        * at the peer_sk to obtain peer_labeling for unix socks this
+        * does not work
+        */
+       if (!new_ctx->label)
+               new_ctx->label = aa_get_label(peer_ctx->label);
+
+       /* Cross reference the peer labels for SO_PEERSEC */
+       if (new_ctx->peer)
+               aa_put_label(new_ctx->peer);
+
+       if (sk_ctx->peer)
+               aa_put_label(sk_ctx->peer);
+
+       new_ctx->peer = aa_get_label(sk_ctx->label);
+       sk_ctx->peer = aa_get_label(peer_ctx->label);
+
+       path = UNIX_FS_CONN_PATH(sk, peer_sk);
+       if (path) {
+               new_ctx->path = *path;
+               sk_ctx->path = *path;
+               path_get(path);
+               path_get(path);
+       }
+       return 0;
+}
+
+/**
+ * apparmor_unix_may_send - check perms before conn or sending unix dgrams
+ *
+ * other is locked when this hook is called
+ *
+ * dgram connect calls may_send, peer setup but path not copied?????
+ */
+static int apparmor_unix_may_send(struct socket *sock, struct socket *peer)
+{
+       struct aa_sk_ctx *peer_ctx = SK_CTX(peer->sk);
+       struct aa_label *label;
+       int error;
+
+       label = __begin_current_label_crit_section();
+       error = xcheck(aa_unix_peer_perm(label, OP_SENDMSG, AA_MAY_SEND,
+                                        sock->sk, peer->sk, NULL),
+                      aa_unix_peer_perm(peer_ctx->label, OP_SENDMSG,
+                                        AA_MAY_RECEIVE,
+                                        peer->sk, sock->sk, label));
+       __end_current_label_crit_section(label);
+
+       return error;
 }
 
 /**
@@ -1056,11 +1151,25 @@ static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 static struct aa_label *sk_peer_label(struct sock *sk)
 {
+       struct sock *peer_sk;
        struct aa_sk_ctx *ctx = SK_CTX(sk);
 
        if (ctx->peer)
                return ctx->peer;
 
+       if (sk->sk_family != PF_UNIX)
+               return ERR_PTR(-ENOPROTOOPT);
+
+       /* check for sockpair peering which does not go through
+        * security_unix_stream_connect
+        */
+       peer_sk = unix_peer(sk);
+       if (peer_sk) {
+               ctx = SK_CTX(peer_sk);
+               if (ctx->label)
+                       return ctx->label;
+       }
+
        return ERR_PTR(-ENOPROTOOPT);
 }
 
@@ -1207,6 +1316,9 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
        LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
        LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
 
+       LSM_HOOK_INIT(unix_stream_connect, apparmor_unix_stream_connect),
+       LSM_HOOK_INIT(unix_may_send, apparmor_unix_may_send),
+
        LSM_HOOK_INIT(socket_create, apparmor_socket_create),
        LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
        LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
index e693df8d0286a0aac47d7f1b8c690e8d16e72024..e2e759b21e44131bd454c1170370b7bddab4e5f9 100644 (file)
@@ -8,6 +8,7 @@
  * Copyright 2009-2017 Canonical Ltd.
  */
 
+#include "include/af_unix.h"
 #include "include/apparmor.h"
 #include "include/audit.h"
 #include "include/cred.h"
@@ -26,6 +27,7 @@ struct aa_sfs_entry aa_sfs_entry_network[] = {
 
 struct aa_sfs_entry aa_sfs_entry_network_compat[] = {
        AA_SFS_FILE_STRING("af_mask",   AA_SFS_AF_MASK),
+       AA_SFS_FILE_BOOLEAN("af_unix",  1),
        { }
 };
 
@@ -71,6 +73,36 @@ static const char * const net_mask_names[] = {
        "unknown",
 };
 
+static void audit_unix_addr(struct audit_buffer *ab, const char *str,
+                           struct sockaddr_un *addr, int addrlen)
+{
+       int len = unix_addr_len(addrlen);
+
+       if (!addr || len <= 0) {
+               audit_log_format(ab, " %s=none", str);
+       } else if (addr->sun_path[0]) {
+               audit_log_format(ab, " %s=", str);
+               audit_log_untrustedstring(ab, addr->sun_path);
+       } else {
+               audit_log_format(ab, " %s=\"@", str);
+               if (audit_string_contains_control(&addr->sun_path[1], len - 1))
+                       audit_log_n_hex(ab, &addr->sun_path[1], len - 1);
+               else
+                       audit_log_format(ab, "%.*s", len - 1,
+                                        &addr->sun_path[1]);
+               audit_log_format(ab, "\"");
+       }
+}
+
+static void audit_unix_sk_addr(struct audit_buffer *ab, const char *str,
+                              struct sock *sk)
+{
+       struct unix_sock *u = unix_sk(sk);
+       if (u && u->addr)
+               audit_unix_addr(ab, str, u->addr->name, u->addr->len);
+       else
+               audit_unix_addr(ab, str, NULL, 0);
+}
 
 /* audit callback for net specific fields */
 void audit_net_cb(struct audit_buffer *ab, void *va)
@@ -102,6 +134,23 @@ void audit_net_cb(struct audit_buffer *ab, void *va)
                                           net_mask_names, NET_PERMS_MASK);
                }
        }
+       if (sa->u.net->family == AF_UNIX) {
+               if ((aad(sa)->request & ~NET_PEER_MASK) && aad(sa)->net.addr)
+                       audit_unix_addr(ab, "addr",
+                                       unix_addr(aad(sa)->net.addr),
+                                       aad(sa)->net.addrlen);
+               else
+                       audit_unix_sk_addr(ab, "addr", sa->u.net->sk);
+               if (aad(sa)->request & NET_PEER_MASK) {
+                       if (aad(sa)->net.addr)
+                               audit_unix_addr(ab, "peer_addr",
+                                               unix_addr(aad(sa)->net.addr),
+                                               aad(sa)->net.addrlen);
+                       else
+                               audit_unix_sk_addr(ab, "peer_addr",
+                                                  aad(sa)->net.peer_sk);
+               }
+       }
        if (aad(sa)->peer) {
                audit_log_format(ab, " peer=");
                aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
@@ -202,7 +251,9 @@ int aa_sock_file_perm(struct aa_label *label, const char *op, u32 request,
        AA_BUG(!sock);
        AA_BUG(!sock->sk);
 
-       return aa_label_sk_perm(label, op, request, sock->sk);
+       return af_select(sock->sk->sk_family,
+                        file_perm(label, op, request, sock),
+                        aa_label_sk_perm(label, op, request, sock->sk));
 }
 
 #ifdef CONFIG_NETWORK_SECMARK