| Kernel v2.6.25-rc7 /security/selinux/hooks.c |
|---|
  2.6.25-rc7
security
selinux
 hooks.c
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9f3124b..41a049f 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -12,8 +12,8 @@
* Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
* <dgoeddel@trustedcs.com>
- * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
- * Paul Moore, <paul.moore@hp.com>
+ * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
+ * Paul Moore <paul.moore@hp.com>
* Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
* Yuichi Nakamura <ynakam@hitachisoft.jp>
*
@@ -50,8 +50,11 @@
#include <net/icmp.h>
#include <net/ip.h> /* for local_port_range[] */
#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
+#include <net/net_namespace.h>
+#include <net/netlabel.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
+#include <asm/atomic.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h> /* for network interface checks */
@@ -76,17 +79,23 @@
#include "avc.h"
#include "objsec.h"
#include "netif.h"
+#include "netnode.h"
#include "xfrm.h"
#include "netlabel.h"
#define XATTR_SELINUX_SUFFIX "selinux"
#define XATTR_NAME_SELINUX XATTR_SECURITY_PREFIX XATTR_SELINUX_SUFFIX
+#define NUM_SEL_MNT_OPTS 4
+
extern unsigned int policydb_loaded_version;
extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
extern int selinux_compat_net;
extern struct security_operations *security_ops;
+/* SECMARK reference count */
+atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
+
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
int selinux_enforcing = 0;
@@ -127,30 +136,19 @@ static DEFINE_SPINLOCK(sb_security_lock);
static struct kmem_cache *sel_inode_cache;
-/* Return security context for a given sid or just the context
- length if the buffer is null or length is 0 */
-static int selinux_getsecurity(u32 sid, void *buffer, size_t size)
+/**
+ * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
+ *
+ * Description:
+ * This function checks the SECMARK reference counter to see if any SECMARK
+ * targets are currently configured, if the reference counter is greater than
+ * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
+ * enabled, false (0) if SECMARK is disabled.
+ *
+ */
+static int selinux_secmark_enabled(void)
{
- char *context;
- unsigned len;
- int rc;
-
- rc = security_sid_to_context(sid, &context, &len);
- if (rc)
- return rc;
-
- if (!buffer || !size)
- goto getsecurity_exit;
-
- if (size < len) {
- len = -ERANGE;
- goto getsecurity_exit;
- }
- memcpy(buffer, context, len);
-
-getsecurity_exit:
- kfree(context);
- return len;
+ return (atomic_read(&selinux_secmark_refcount) > 0);
}
/* Allocate and free functions for each kind of security blob. */
@@ -321,8 +319,8 @@ enum {
Opt_error = -1,
Opt_context = 1,
Opt_fscontext = 2,
- Opt_defcontext = 4,
- Opt_rootcontext = 8,
+ Opt_defcontext = 3,
+ Opt_rootcontext = 4,
};
static match_table_t tokens = {
@@ -366,150 +364,325 @@ static int may_context_mount_inode_relabel(u32 sid,
return rc;
}
-static int try_context_mount(struct super_block *sb, void *data)
+static int sb_finish_set_opts(struct super_block *sb)
{
- char *context = NULL, *defcontext = NULL;
- char *fscontext = NULL, *rootcontext = NULL;
- const char *name;
- u32 sid;
- int alloc = 0, rc = 0, seen = 0;
- struct task_security_struct *tsec = current->security;
struct superblock_security_struct *sbsec = sb->s_security;
+ struct dentry *root = sb->s_root;
+ struct inode *root_inode = root->d_inode;
+ int rc = 0;
- if (!data)
- goto out;
+ if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
+ /* Make sure that the xattr handler exists and that no
+ error other than -ENODATA is returned by getxattr on
+ the root directory. -ENODATA is ok, as this may be
+ the first boot of the SELinux kernel before we have
+ assigned xattr values to the filesystem. */
+ if (!root_inode->i_op->getxattr) {
+ printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
+ "xattr support\n", sb->s_id, sb->s_type->name);
+ rc = -EOPNOTSUPP;
+ goto out;
+ }
+ rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
+ if (rc < 0 && rc != -ENODATA) {
+ if (rc == -EOPNOTSUPP)
+ printk(KERN_WARNING "SELinux: (dev %s, type "
+ "%s) has no security xattr handler\n",
+ sb->s_id, sb->s_type->name);
+ else
+ printk(KERN_WARNING "SELinux: (dev %s, type "
+ "%s) getxattr errno %d\n", sb->s_id,
+ sb->s_type->name, -rc);
+ goto out;
+ }
+ }
- name = sb->s_type->name;
+ sbsec->initialized = 1;
- if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA) {
+ if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
+ printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
+ sb->s_id, sb->s_type->name);
+ else
+ printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
+ sb->s_id, sb->s_type->name,
+ labeling_behaviors[sbsec->behavior-1]);
- /* NFS we understand. */
- if (!strcmp(name, "nfs")) {
- struct nfs_mount_data *d = data;
+ /* Initialize the root inode. */
+ rc = inode_doinit_with_dentry(root_inode, root);
- if (d->version < NFS_MOUNT_VERSION)
- goto out;
+ /* Initialize any other inodes associated with the superblock, e.g.
+ inodes created prior to initial policy load or inodes created
+ during get_sb by a pseudo filesystem that directly
+ populates itself. */
+ spin_lock(&sbsec->isec_lock);
+next_inode:
+ if (!list_empty(&sbsec->isec_head)) {
+ struct inode_security_struct *isec =
+ list_entry(sbsec->isec_head.next,
+ struct inode_security_struct, list);
+ struct inode *inode = isec->inode;
+ spin_unlock(&sbsec->isec_lock);
+ inode = igrab(inode);
+ if (inode) {
+ if (!IS_PRIVATE(inode))
+ inode_doinit(inode);
+ iput(inode);
+ }
+ spin_lock(&sbsec->isec_lock);
+ list_del_init(&isec->list);
+ goto next_inode;
+ }
+ spin_unlock(&sbsec->isec_lock);
+out:
+ return rc;
+}
- if (d->context[0]) {
- context = d->context;
- seen |= Opt_context;
- }
- } else
- goto out;
+/*
+ * This function should allow an FS to ask what it's mount security
+ * options were so it can use those later for submounts, displaying
+ * mount options, or whatever.
+ */
+static int selinux_get_mnt_opts(const struct super_block *sb,
+ struct security_mnt_opts *opts)
+{
+ int rc = 0, i;
+ struct superblock_security_struct *sbsec = sb->s_security;
+ char *context = NULL;
+ u32 len;
+ char tmp;
- } else {
- /* Standard string-based options. */
- char *p, *options = data;
+ security_init_mnt_opts(opts);
- while ((p = strsep(&options, "|")) != NULL) {
- int token;
- substring_t args[MAX_OPT_ARGS];
+ if (!sbsec->initialized)
+ return -EINVAL;
- if (!*p)
- continue;
+ if (!ss_initialized)
+ return -EINVAL;
- token = match_token(p, tokens, args);
+ /*
+ * if we ever use sbsec flags for anything other than tracking mount
+ * settings this is going to need a mask
+ */
+ tmp = sbsec->flags;
+ /* count the number of mount options for this sb */
+ for (i = 0; i < 8; i++) {
+ if (tmp & 0x01)
+ opts->num_mnt_opts++;
+ tmp >>= 1;
+ }
- switch (token) {
- case Opt_context:
- if (seen & (Opt_context|Opt_defcontext)) {
- rc = -EINVAL;
- printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
- goto out_free;
- }
- context = match_strdup(&args[0]);
- if (!context) {
- rc = -ENOMEM;
- goto out_free;
- }
- if (!alloc)
- alloc = 1;
- seen |= Opt_context;
- break;
+ opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
+ if (!opts->mnt_opts) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
- case Opt_fscontext:
- if (seen & Opt_fscontext) {
- rc = -EINVAL;
- printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
- goto out_free;
- }
- fscontext = match_strdup(&args[0]);
- if (!fscontext) {
- rc = -ENOMEM;
- goto out_free;
- }
- if (!alloc)
- alloc = 1;
- seen |= Opt_fscontext;
- break;
+ opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
+ if (!opts->mnt_opts_flags) {
+ rc = -ENOMEM;
+ goto out_free;
+ }
- case Opt_rootcontext:
- if (seen & Opt_rootcontext) {
- rc = -EINVAL;
- printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
- goto out_free;
- }
- rootcontext = match_strdup(&args[0]);
- if (!rootcontext) {
- rc = -ENOMEM;
- goto out_free;
- }
- if (!alloc)
- alloc = 1;
- seen |= Opt_rootcontext;
- break;
+ i = 0;
+ if (sbsec->flags & FSCONTEXT_MNT) {
+ rc = security_sid_to_context(sbsec->sid, &context, &len);
+ if (rc)
+ goto out_free;
+ opts->mnt_opts[i] = context;
+ opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
+ }
+ if (sbsec->flags & CONTEXT_MNT) {
+ rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
+ if (rc)
+ goto out_free;
+ opts->mnt_opts[i] = context;
+ opts->mnt_opts_flags[i++] = CONTEXT_MNT;
+ }
+ if (sbsec->flags & DEFCONTEXT_MNT) {
+ rc = security_sid_to_context(sbsec->def_sid, &context, &len);
+ if (rc)
+ goto out_free;
+ opts->mnt_opts[i] = context;
+ opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
+ }
+ if (sbsec->flags & ROOTCONTEXT_MNT) {
+ struct inode *root = sbsec->sb->s_root->d_inode;
+ struct inode_security_struct *isec = root->i_security;
- case Opt_defcontext:
- if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
- rc = -EINVAL;
- printk(KERN_WARNING "SELinux: "
- "defcontext option is invalid "
- "for this filesystem type\n");
- goto out_free;
- }
- if (seen & (Opt_context|Opt_defcontext)) {
- rc = -EINVAL;
- printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
- goto out_free;
- }
- defcontext = match_strdup(&args[0]);
- if (!defcontext) {
- rc = -ENOMEM;
- goto out_free;
- }
- if (!alloc)
- alloc = 1;
- seen |= Opt_defcontext;
- break;
+ rc = security_sid_to_context(isec->sid, &context, &len);
+ if (rc)
+ goto out_free;
+ opts->mnt_opts[i] = context;
+ opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
+ }
- default:
- rc = -EINVAL;
- printk(KERN_WARNING "SELinux: unknown mount "
- "option\n");
- goto out_free;
+ BUG_ON(i != opts->num_mnt_opts);
- }
+ return 0;
+
+out_free:
+ security_free_mnt_opts(opts);
+ return rc;
+}
+
+static int bad_option(struct superblock_security_struct *sbsec, char flag,
+ u32 old_sid, u32 new_sid)
+{
+ /* check if the old mount command had the same options */
+ if (sbsec->initialized)
+ if (!(sbsec->flags & flag) ||
+ (old_sid != new_sid))
+ return 1;
+
+ /* check if we were passed the same options twice,
+ * aka someone passed context=a,context=b
+ */
+ if (!sbsec->initialized)
+ if (sbsec->flags & flag)
+ return 1;
+ return 0;
+}
+
+/*
+ * Allow filesystems with binary mount data to explicitly set mount point
+ * labeling information.
+ */
+static int selinux_set_mnt_opts(struct super_block *sb,
+ struct security_mnt_opts *opts)
+{
+ int rc = 0, i;
+ struct task_security_struct *tsec = current->security;
+ struct superblock_security_struct *sbsec = sb->s_security;
+ const char *name = sb->s_type->name;
+ struct inode *inode = sbsec->sb->s_root->d_inode;
+ struct inode_security_struct *root_isec = inode->i_security;
+ u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
+ u32 defcontext_sid = 0;
+ char **mount_options = opts->mnt_opts;
+ int *flags = opts->mnt_opts_flags;
+ int num_opts = opts->num_mnt_opts;
+
+ mutex_lock(&sbsec->lock);
+
+ if (!ss_initialized) {
+ if (!num_opts) {
+ /* Defer initialization until selinux_complete_init,
+ after the initial policy is loaded and the security
+ server is ready to handle calls. */
+ spin_lock(&sb_security_lock);
+ if (list_empty(&sbsec->list))
+ list_add(&sbsec->list, &superblock_security_head);
+ spin_unlock(&sb_security_lock);
+ goto out;
}
+ rc = -EINVAL;
+ printk(KERN_WARNING "Unable to set superblock options before "
+ "the security server is initialized\n");
+ goto out;
}
- if (!seen)
- goto out;
+ /*
+ * Binary mount data FS will come through this function twice. Once
+ * from an explicit call and once from the generic calls from the vfs.
+ * Since the generic VFS calls will not contain any security mount data
+ * we need to skip the double mount verification.
+ *
+ * This does open a hole in which we will not notice if the first
+ * mount using this sb set explict options and a second mount using
+ * this sb does not set any security options. (The first options
+ * will be used for both mounts)
+ */
+ if (sbsec->initialized && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
+ && (num_opts == 0))
+ goto out;
- /* sets the context of the superblock for the fs being mounted. */
- if (fscontext) {
- rc = security_context_to_sid(fscontext, strlen(fscontext), &sid);
+ /*
+ * parse the mount options, check if they are valid sids.
+ * also check if someone is trying to mount the same sb more
+ * than once with different security options.
+ */
+ for (i = 0; i < num_opts; i++) {
+ u32 sid;
+ rc = security_context_to_sid(mount_options[i],
+ strlen(mount_options[i]), &sid);
if (rc) {
printk(KERN_WARNING "SELinux: security_context_to_sid"
"(%s) failed for (dev %s, type %s) errno=%d\n",
- fscontext, sb->s_id, name, rc);
- goto out_free;
+ mount_options[i], sb->s_id, name, rc);
+ goto out;
+ }
+ switch (flags[i]) {
+ case FSCONTEXT_MNT:
+ fscontext_sid = sid;
+
+ if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
+ fscontext_sid))
+ goto out_double_mount;
+
+ sbsec->flags |= FSCONTEXT_MNT;
+ break;
+ case CONTEXT_MNT:
+ context_sid = sid;
+
+ if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
+ context_sid))
+ goto out_double_mount;
+
+ sbsec->flags |= CONTEXT_MNT;
+ break;
+ case ROOTCONTEXT_MNT:
+ rootcontext_sid = sid;
+
+ if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
+ rootcontext_sid))
+ goto out_double_mount;
+
+ sbsec->flags |= ROOTCONTEXT_MNT;
+
+ break;
+ case DEFCONTEXT_MNT:
+ defcontext_sid = sid;
+
+ if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
+ defcontext_sid))
+ goto out_double_mount;
+
+ sbsec->flags |= DEFCONTEXT_MNT;
+
+ break;
+ default:
+ rc = -EINVAL;
+ goto out;
}
+ }
+
+ if (sbsec->initialized) {
+ /* previously mounted with options, but not on this attempt? */
+ if (sbsec->flags && !num_opts)
+ goto out_double_mount;
+ rc = 0;
+ goto out;
+ }
+
+ if (strcmp(sb->s_type->name, "proc") == 0)
+ sbsec->proc = 1;
+
+ /* Determine the labeling behavior to use for this filesystem type. */
+ rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
+ if (rc) {
+ printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
+ __FUNCTION__, sb->s_type->name, rc);
+ goto out;
+ }
- rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
+ /* sets the context of the superblock for the fs being mounted. */
+ if (fscontext_sid) {
+
+ rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, tsec);
if (rc)
- goto out_free;
+ goto out;
- sbsec->sid = sid;
+ sbsec->sid = fscontext_sid;
}
/*
@@ -517,182 +690,260 @@ static int try_context_mount(struct super_block *sb, void *data)
* sets the label used on all file below the mountpoint, and will set
* the superblock context if not already set.
*/
- if (context) {
- rc = security_context_to_sid(context, strlen(context), &sid);
- if (rc) {
- printk(KERN_WARNING "SELinux: security_context_to_sid"
- "(%s) failed for (dev %s, type %s) errno=%d\n",
- context, sb->s_id, name, rc);
- goto out_free;
- }
-
- if (!fscontext) {
- rc = may_context_mount_sb_relabel(sid, sbsec, tsec);
+ if (context_sid) {
+ if (!fscontext_sid) {
+ rc = may_context_mount_sb_relabel(context_sid, sbsec, tsec);
if (rc)
- goto out_free;
- sbsec->sid = sid;
+ goto out;
+ sbsec->sid = context_sid;
} else {
- rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
+ rc = may_context_mount_inode_relabel(context_sid, sbsec, tsec);
if (rc)
- goto out_free;
+ goto out;
}
- sbsec->mntpoint_sid = sid;
+ if (!rootcontext_sid)
+ rootcontext_sid = context_sid;
+ sbsec->mntpoint_sid = context_sid;
sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
}
- if (rootcontext) {
- struct inode *inode = sb->s_root->d_inode;
- struct inode_security_struct *isec = inode->i_security;
- rc = security_context_to_sid(rootcontext, strlen(rootcontext), &sid);
- if (rc) {
- printk(KERN_WARNING "SELinux: security_context_to_sid"
- "(%s) failed for (dev %s, type %s) errno=%d\n",
- rootcontext, sb->s_id, name, rc);
- goto out_free;
- }
-
- rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
+ if (rootcontext_sid) {
+ rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec, tsec);
if (rc)
- goto out_free;
+ goto out;
- isec->sid = sid;
- isec->initialized = 1;
+ root_isec->sid = rootcontext_sid;
+ root_isec->initialized = 1;
}
- if (defcontext) {
- rc = security_context_to_sid(defcontext, strlen(defcontext), &sid);
- if (rc) {
- printk(KERN_WARNING "SELinux: security_context_to_sid"
- "(%s) failed for (dev %s, type %s) errno=%d\n",
- defcontext, sb->s_id, name, rc);
- goto out_free;
+ if (defcontext_sid) {
+ if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
+ rc = -EINVAL;
+ printk(KERN_WARNING "SELinux: defcontext option is "
+ "invalid for this filesystem type\n");
+ goto out;
}
- if (sid == sbsec->def_sid)
- goto out_free;
-
- rc = may_context_mount_inode_relabel(sid, sbsec, tsec);
- if (rc)
- goto out_free;
+ if (defcontext_sid != sbsec->def_sid) {
+ rc = may_context_mount_inode_relabel(defcontext_sid,
+ sbsec, tsec);
+ if (rc)
+ goto out;
+ }
- sbsec->def_sid = sid;
+ sbsec->def_sid = defcontext_sid;
}
-out_free:
- if (alloc) {
- kfree(context);
- kfree(defcontext);
- kfree(fscontext);
- kfree(rootcontext);
- }
+ rc = sb_finish_set_opts(sb);
out:
+ mutex_unlock(&sbsec->lock);
return rc;
+out_double_mount:
+ rc = -EINVAL;
+ printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
+ "security settings for (dev %s, type %s)\n", sb->s_id, name);
+ goto out;
}
-static int superblock_doinit(struct super_block *sb, void *data)
+static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
+ struct super_block *newsb)
{
- struct superblock_security_struct *sbsec = sb->s_security;
- struct dentry *root = sb->s_root;
- struct inode *inode = root->d_inode;
- int rc = 0;
+ const struct superblock_security_struct *oldsbsec = oldsb->s_security;
+ struct superblock_security_struct *newsbsec = newsb->s_security;
- mutex_lock(&sbsec->lock);
- if (sbsec->initialized)
- goto out;
+ int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
+ int set_context = (oldsbsec->flags & CONTEXT_MNT);
+ int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
- if (!ss_initialized) {
- /* Defer initialization until selinux_complete_init,
- after the initial policy is loaded and the security
- server is ready to handle calls. */
- spin_lock(&sb_security_lock);
- if (list_empty(&sbsec->list))
- list_add(&sbsec->list, &superblock_security_head);
- spin_unlock(&sb_security_lock);
- goto out;
+ /* we can't error, we can't save the info, this shouldn't get called
+ * this early in the boot process. */
+ BUG_ON(!ss_initialized);
+
+ /* this might go away sometime down the line if there is a new user
+ * of clone, but for now, nfs better not get here... */
+ BUG_ON(newsbsec->initialized);
+
+ /* how can we clone if the old one wasn't set up?? */
+ BUG_ON(!oldsbsec->initialized);
+
+ mutex_lock(&newsbsec->lock);
+
+ newsbsec->flags = oldsbsec->flags;
+
+ newsbsec->sid = oldsbsec->sid;
+ newsbsec->def_sid = oldsbsec->def_sid;
+ newsbsec->behavior = oldsbsec->behavior;
+
+ if (set_context) {
+ u32 sid = oldsbsec->mntpoint_sid;
+
+ if (!set_fscontext)
+ newsbsec->sid = sid;
+ if (!set_rootcontext) {
+ struct inode *newinode = newsb->s_root->d_inode;
+ struct inode_security_struct *newisec = newinode->i_security;
+ newisec->sid = sid;
+ }
+ newsbsec->mntpoint_sid = sid;
}
+ if (set_rootcontext) {
+ const struct inode *oldinode = oldsb->s_root->d_inode;
+ const struct inode_security_struct *oldisec = oldinode->i_security;
+ struct inode *newinode = newsb->s_root->d_inode;
+ struct inode_security_struct *newisec = newinode->i_security;
- /* Determine the labeling behavior to use for this filesystem type. */
- rc = security_fs_use(sb->s_type->name, &sbsec->behavior, &sbsec->sid);
- if (rc) {
- printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
- __FUNCTION__, sb->s_type->name, rc);
- goto out;
+ newisec->sid = oldisec->sid;
}
- rc = try_context_mount(sb, data);
- if (rc)
- goto out;
+ sb_finish_set_opts(newsb);
+ mutex_unlock(&newsbsec->lock);
+}
+
+static int selinux_parse_opts_str(char *options,
+ struct security_mnt_opts *opts)
+{
+ char *p;
+ char *context = NULL, *defcontext = NULL;
+ char *fscontext = NULL, *rootcontext = NULL;
+ int rc, num_mnt_opts = 0;
+
+ opts->num_mnt_opts = 0;
+
+ /* Standard string-based options. */
+ while ((p = strsep(&options, "|")) != NULL) {
+ int token;
+ substring_t args[MAX_OPT_ARGS];
+
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+
+ switch (token) {
+ case Opt_context:
+ if (context || defcontext) {
+ rc = -EINVAL;
+ printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
+ goto out_err;
+ }
+ context = match_strdup(&args[0]);
+ if (!context) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+ break;
+
+ case Opt_fscontext:
+ if (fscontext) {
+ rc = -EINVAL;
+ printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
+ goto out_err;
+ }
+ fscontext = match_strdup(&args[0]);
+ if (!fscontext) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+ break;
+
+ case Opt_rootcontext:
+ if (rootcontext) {
+ rc = -EINVAL;
+ printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
+ goto out_err;
+ }
+ rootcontext = match_strdup(&args[0]);
+ if (!rootcontext) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+ break;
+
+ case Opt_defcontext:
+ if (context || defcontext) {
+ rc = -EINVAL;
+ printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
+ goto out_err;
+ }
+ defcontext = match_strdup(&args[0]);
+ if (!defcontext) {
+ rc = -ENOMEM;
+ goto out_err;
+ }
+ break;
+
+ default:
+ rc = -EINVAL;
+ printk(KERN_WARNING "SELinux: unknown mount option\n");
+ goto out_err;
- if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
- /* Make sure that the xattr handler exists and that no
- error other than -ENODATA is returned by getxattr on
- the root directory. -ENODATA is ok, as this may be
- the first boot of the SELinux kernel before we have
- assigned xattr values to the filesystem. */
- if (!inode->i_op->getxattr) {
- printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
- "xattr support\n", sb->s_id, sb->s_type->name);
- rc = -EOPNOTSUPP;
- goto out;
- }
- rc = inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
- if (rc < 0 && rc != -ENODATA) {
- if (rc == -EOPNOTSUPP)
- printk(KERN_WARNING "SELinux: (dev %s, type "
- "%s) has no security xattr handler\n",
- sb->s_id, sb->s_type->name);
- else
- printk(KERN_WARNING "SELinux: (dev %s, type "
- "%s) getxattr errno %d\n", sb->s_id,
- sb->s_type->name, -rc);
- goto out;
}
}
- if (strcmp(sb->s_type->name, "proc") == 0)
- sbsec->proc = 1;
-
- sbsec->initialized = 1;
+ rc = -ENOMEM;
+ opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
+ if (!opts->mnt_opts)
+ goto out_err;
+
+ opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
+ if (!opts->mnt_opts_flags) {
+ kfree(opts->mnt_opts);
+ goto out_err;
+ }
- if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors)) {
- printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
- sb->s_id, sb->s_type->name);
+ if (fscontext) {
+ opts->mnt_opts[num_mnt_opts] = fscontext;
+ opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
}
- else {
- printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
- sb->s_id, sb->s_type->name,
- labeling_behaviors[sbsec->behavior-1]);
+ if (context) {
+ opts->mnt_opts[num_mnt_opts] = context;
+ opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
+ }
+ if (rootcontext) {
+ opts->mnt_opts[num_mnt_opts] = rootcontext;
+ opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
+ }
+ if (defcontext) {
+ opts->mnt_opts[num_mnt_opts] = defcontext;
+ opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
}
- /* Initialize the root inode. */
- rc = inode_doinit_with_dentry(sb->s_root->d_inode, sb->s_root);
+ opts->num_mnt_opts = num_mnt_opts;
+ return 0;
+
+out_err:
+ kfree(context);
+ kfree(defcontext);
+ kfree(fscontext);
+ kfree(rootcontext);
+ return rc;
+}
+/*
+ * string mount options parsing and call set the sbsec
+ */
+static int superblock_doinit(struct super_block *sb, void *data)
+{
+ int rc = 0;
+ char *options = data;
+ struct security_mnt_opts opts;
+
+ security_init_mnt_opts(&opts);
+
+ if (!data)
+ goto out;
+
+ BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
+
+ rc = selinux_parse_opts_str(options, &opts);
+ if (rc)
+ goto out_err;
- /* Initialize any other inodes associated with the superblock, e.g.
- inodes created prior to initial policy load or inodes created
- during get_sb by a pseudo filesystem that directly
- populates itself. */
- spin_lock(&sbsec->isec_lock);
-next_inode:
- if (!list_empty(&sbsec->isec_head)) {
- struct inode_security_struct *isec =
- list_entry(sbsec->isec_head.next,
- struct inode_security_struct, list);
- struct inode *inode = isec->inode;
- spin_unlock(&sbsec->isec_lock);
- inode = igrab(inode);
- if (inode) {
- if (!IS_PRIVATE (inode))
- inode_doinit(inode);
- iput(inode);
- }
- spin_lock(&sbsec->isec_lock);
- list_del_init(&isec->list);
- goto next_inode;
- }
- spin_unlock(&sbsec->isec_lock);
out:
- mutex_unlock(&sbsec->lock);
+ rc = selinux_set_mnt_opts(sb, &opts);
+
+out_err:
+ security_free_mnt_opts(&opts);
return rc;
}
@@ -1039,12 +1290,18 @@ static int task_has_perm(struct task_struct *tsk1,
SECCLASS_PROCESS, perms, NULL);
}
+#if CAP_LAST_CAP > 63
+#error Fix SELinux to handle capabilities > 63.
+#endif
+
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
int cap)
{
struct task_security_struct *tsec;
struct avc_audit_data ad;
+ u16 sclass;
+ u32 av = CAP_TO_MASK(cap);
tsec = tsk->security;
@@ -1052,8 +1309,19 @@ static int task_has_capability(struct task_struct *tsk,
ad.tsk = tsk;
ad.u.cap = cap;
- return avc_has_perm(tsec->sid, tsec->sid,
- SECCLASS_CAPABILITY, CAP_TO_MASK(cap), &ad);
+ switch (CAP_TO_INDEX(cap)) {
+ case 0:
+ sclass = SECCLASS_CAPABILITY;
+ break;
+ case 1:
+ sclass = SECCLASS_CAPABILITY2;
+ break;
+ default:
+ printk(KERN_ERR
+ "SELinux: out of range capability %d\n", cap);
+ BUG();
+ }
+ return avc_has_perm(tsec->sid, tsec->sid, sclass, av, &ad);
}
/* Check whether a task is allowed to use a system operation. */
@@ -1106,8 +1374,8 @@ static inline int dentry_has_perm(struct task_struct *tsk,
struct inode *inode = dentry->d_inode;
struct avc_audit_data ad;
AVC_AUDIT_DATA_INIT(&ad,FS);
- ad.u.fs.mnt = mnt;
- ad.u.fs.dentry = dentry;
+ ad.u.fs.path.mnt = mnt;
+ ad.u.fs.path.dentry = dentry;
return inode_has_perm(tsk, inode, av, &ad);
}
@@ -1125,15 +1393,12 @@ static int file_has_perm(struct task_struct *tsk,
{
struct task_security_struct *tsec = tsk->security;
struct file_security_struct *fsec = file->f_security;
- struct vfsmount *mnt = file->f_path.mnt;
- struct dentry *dentry = file->f_path.dentry;
- struct inode *inode = dentry->d_inode;
+ struct inode *inode = file->f_path.dentry->d_inode;
struct avc_audit_data ad;
int rc;
AVC_AUDIT_DATA_INIT(&ad, FS);
- ad.u.fs.mnt = mnt;
- ad.u.fs.dentry = dentry;
+ ad.u.fs.path = file->f_path;
if (tsec->sid != fsec->sid) {
rc = avc_has_perm(tsec->sid, fsec->sid,
@@ -1168,7 +1433,7 @@ static int may_create(struct inode *dir,
sbsec = dir->i_sb->s_security;
AVC_AUDIT_DATA_INIT(&ad, FS);
- ad.u.fs.dentry = dentry;
+ ad.u.fs.path.dentry = dentry;
rc = avc_has_perm(tsec->sid, dsec->sid, SECCLASS_DIR,
DIR__ADD_NAME | DIR__SEARCH,
@@ -1226,7 +1491,7 @@ static int may_link(struct inode *dir,
isec = dentry->d_inode->i_security;
AVC_AUDIT_DATA_INIT(&ad, FS);
- ad.u.fs.dentry = dentry;
+ ad.u.fs.path.dentry = dentry;
av = DIR__SEARCH;
av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
@@ -1273,7 +1538,7 @@ static inline int may_rename(struct inode *old_dir,
AVC_AUDIT_DATA_INIT(&ad, FS);
- ad.u.fs.dentry = old_dentry;
+ ad.u.fs.path.dentry = old_dentry;
rc = avc_has_perm(tsec->sid, old_dsec->sid, SECCLASS_DIR,
DIR__REMOVE_NAME | DIR__SEARCH, &ad);
if (rc)
@@ -1289,7 +1554,7 @@ static inline int may_rename(struct inode *old_dir,
return rc;
}
- ad.u.fs.dentry = new_dentry;
+ ad.u.fs.path.dentry = new_dentry;
av = DIR__ADD_NAME | DIR__SEARCH;
if (new_dentry->d_inode)
av |= DIR__REMOVE_NAME;
@@ -1668,8 +1933,7 @@ static int selinux_bprm_set_security(struct linux_binprm *bprm)
}
AVC_AUDIT_DATA_INIT(&ad, FS);
- ad.u.fs.mnt = bprm->file->f_path.mnt;
- ad.u.fs.dentry = bprm->file->f_path.dentry;
+ ad.u.fs.path = bprm->file->f_path;
if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
newsid = tsec->sid;
@@ -2007,7 +2271,7 @@ static inline void take_selinux_option(char **to, char *from, int *first,
}
}
-static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void *copy)
+static int selinux_sb_copy_data(char *orig, char *copy)
{
int fnosec, fsec, rc = 0;
char *in_save, *in_curr, *in_end;
@@ -2017,12 +2281,6 @@ static int selinux_sb_copy_data(struct file_system_type *type, void *orig, void
in_curr = orig;
sec_curr = copy;
- /* Binary mount data: just copy */
- if (type->fs_flags & FS_BINARY_MOUNTDATA) {
- copy_page(sec_curr, in_curr);
- goto out;
- }
-
nosec = (char *)get_zeroed_page(GFP_KERNEL);
if (!nosec) {
rc = -ENOMEM;
@@ -2065,7 +2323,7 @@ static int selinux_sb_kern_mount(struct super_block *sb, void *data)
return rc;
AVC_AUDIT_DATA_INIT(&ad,FS);
- ad.u.fs.dentry = sb->s_root;
+ ad.u.fs.path.dentry = sb->s_root;
return superblock_has_perm(current, sb, FILESYSTEM__MOUNT, &ad);
}
@@ -2074,7 +2332,7 @@ static int selinux_sb_statfs(struct dentry *dentry)
struct avc_audit_data ad;
AVC_AUDIT_DATA_INIT(&ad,FS);
- ad.u.fs.dentry = dentry->d_sb->s_root;
+ ad.u.fs.path.dentry = dentry->d_sb->s_root;
return superblock_has_perm(current, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
}
@@ -2091,10 +2349,10 @@ static int selinux_mount(char * dev_name,
return rc;
if (flags & MS_REMOUNT)
- return superblock_has_perm(current, nd->mnt->mnt_sb,
+ return superblock_has_perm(current, nd->path.mnt->mnt_sb,
FILESYSTEM__REMOUNT, NULL);
else
- return dentry_has_perm(current, nd->mnt, nd->dentry,
+ return dentry_has_perm(current, nd->path.mnt, nd->path.dentry,
FILE__MOUNTON);
}
@@ -2337,7 +2595,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, char *name, void *value
return -EPERM;
AVC_AUDIT_DATA_INIT(&ad,FS);
- ad.u.fs.dentry = dentry;
+ ad.u.fs.path.dentry = dentry;
rc = avc_has_perm(tsec->sid, isec->sid, isec->sclass,
FILE__RELABELFROM, &ad);
@@ -2416,14 +2674,27 @@ static int selinux_inode_removexattr (struct dentry *dentry, char *name)
*
* Permission check is handled by selinux_inode_getxattr hook.
*/
-static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void *buffer, size_t size, int err)
+static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
{
+ u32 size;
+ int error;
+ char *context = NULL;
struct inode_security_struct *isec = inode->i_security;
if (strcmp(name, XATTR_SELINUX_SUFFIX))
return -EOPNOTSUPP;
- return selinux_getsecurity(isec->sid, buffer, size);
+ error = security_sid_to_context(isec->sid, &context, &size);
+ if (error)
+ return error;
+ error = size;
+ if (alloc) {
+ *buffer = context;
+ goto out_nofree;
+ }
+ kfree(context);
+out_nofree:
+ return error;
}
static int selinux_inode_setsecurity(struct inode *inode, const char *name,
@@ -3158,7 +3429,7 @@ out:
#endif /* IPV6 */
static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
- char **addrp, int *len, int src, u8 *proto)
+ char **addrp, int src, u8 *proto)
{
int ret = 0;
@@ -3167,7 +3438,6 @@ static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
ret = selinux_parse_skb_ipv4(skb, ad, proto);
if (ret || !addrp)
break;
- *len = 4;
*addrp = (char *)(src ? &ad->u.net.v4info.saddr :
&ad->u.net.v4info.daddr);
break;
@@ -3177,7 +3447,6 @@ static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
ret = selinux_parse_skb_ipv6(skb, ad, proto);
if (ret || !addrp)
break;
- *len = 16;
*addrp = (char *)(src ? &ad->u.net.v6info.saddr :
&ad->u.net.v6info.daddr);
break;
@@ -3186,36 +3455,48 @@ static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
break;
}
+ if (unlikely(ret))
+ printk(KERN_WARNING
+ "SELinux: failure in selinux_parse_skb(),"
+ " unable to parse packet\n");
+
return ret;
}
/**
- * selinux_skb_extlbl_sid - Determine the external label of a packet
+ * selinux_skb_peerlbl_sid - Determine the peer label of a packet
* @skb: the packet
- * @sid: the packet's SID
+ * @family: protocol family
+ * @sid: the packet's peer label SID
*
* Description:
- * Check the various different forms of external packet labeling and determine
- * the external SID for the packet. If only one form of external labeling is
- * present then it is used, if both labeled IPsec and NetLabel labels are
- * present then the SELinux type information is taken from the labeled IPsec
- * SA and the MLS sensitivity label information is taken from the NetLabel
- * security attributes. This bit of "magic" is done in the call to
- * selinux_netlbl_skbuff_getsid().
+ * Check the various different forms of network peer labeling and determine
+ * the peer label/SID for the packet; most of the magic actually occurs in
+ * the security server function security_net_peersid_cmp(). The function
+ * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
+ * or -EACCES if @sid is invalid due to inconsistencies with the different
+ * peer labels.
*
*/
-static void selinux_skb_extlbl_sid(struct sk_buff *skb, u32 *sid)
+static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
{
+ int err;
u32 xfrm_sid;
u32 nlbl_sid;
+ u32 nlbl_type;
selinux_skb_xfrm_sid(skb, &xfrm_sid);
- if (selinux_netlbl_skbuff_getsid(skb,
- (xfrm_sid == SECSID_NULL ?
- SECINITSID_NETMSG : xfrm_sid),
- &nlbl_sid) != 0)
- nlbl_sid = SECSID_NULL;
- *sid = (nlbl_sid == SECSID_NULL ? xfrm_sid : nlbl_sid);
+ selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
+
+ err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
+ if (unlikely(err)) {
+ printk(KERN_WARNING
+ "SELinux: failure in selinux_skb_peerlbl_sid(),"
+ " unable to determine packet's peer label\n");
+ return -EACCES;
+ }
+
+ return 0;
}
/* socket security operations */
@@ -3281,6 +3562,7 @@ static int selinux_socket_post_create(struct socket *sock, int family,
if (sock->sk) {
sksec = sock->sk->sk_security;
sksec->sid = isec->sid;
+ sksec->sclass = isec->sclass;
err = selinux_netlbl_socket_post_create(sock);
}
@@ -3373,7 +3655,7 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in
break;
}
- err = security_node_sid(family, addrp, addrlen, &sid);
+ err = sel_netnode_sid(addrp, family, &sid);
if (err)
goto out;
@@ -3584,131 +3866,182 @@ static int selinux_socket_unix_may_send(struct socket *sock,
return 0;
}
-static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
- struct avc_audit_data *ad, u16 family, char *addrp, int len)
+static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
+ u32 peer_sid,
+ struct avc_audit_data *ad)
{
- int err = 0;
- u32 netif_perm, node_perm, node_sid, if_sid, recv_perm = 0;
- struct socket *sock;
- u16 sock_class = 0;
- u32 sock_sid = 0;
-
- read_lock_bh(&sk->sk_callback_lock);
- sock = sk->sk_socket;
- if (sock) {
- struct inode *inode;
- inode = SOCK_INODE(sock);
- if (inode) {
- struct inode_security_struct *isec;
- isec = inode->i_security;
- sock_sid = isec->sid;
- sock_class = isec->sclass;
- }
- }
- read_unlock_bh(&sk->sk_callback_lock);
- if (!sock_sid)
- goto out;
+ int err;
+ u32 if_sid;
+ u32 node_sid;
- if (!skb->dev)
- goto out;
+ err = sel_netif_sid(ifindex, &if_sid);
+ if (err)
+ return err;
+ err = avc_has_perm(peer_sid, if_sid,
+ SECCLASS_NETIF, NETIF__INGRESS, ad);
+ if (err)
+ return err;
- err = sel_netif_sids(skb->dev, &if_sid, NULL);
+ err = sel_netnode_sid(addrp, family, &node_sid);
if (err)
- goto out;
+ return err;
+ return avc_has_perm(peer_sid, node_sid,
+ SECCLASS_NODE, NODE__RECVFROM, ad);
+}
- switch (sock_class) {
+static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
+ struct sk_buff *skb,
+ struct avc_audit_data *ad,
+ u16 family,
+ char *addrp)
+{
+ int err;
+ struct sk_security_struct *sksec = sk->sk_security;
+ u16 sk_class;
+ u32 netif_perm, node_perm, recv_perm;
+ u32 port_sid, node_sid, if_sid, sk_sid;
+
+ sk_sid = sksec->sid;
+ sk_class = sksec->sclass;
+
+ switch (sk_class) {
case SECCLASS_UDP_SOCKET:
netif_perm = NETIF__UDP_RECV;
node_perm = NODE__UDP_RECV;
recv_perm = UDP_SOCKET__RECV_MSG;
break;
-
case SECCLASS_TCP_SOCKET:
netif_perm = NETIF__TCP_RECV;
node_perm = NODE__TCP_RECV;
recv_perm = TCP_SOCKET__RECV_MSG;
break;
-
case SECCLASS_DCCP_SOCKET:
netif_perm = NETIF__DCCP_RECV;
node_perm = NODE__DCCP_RECV;
recv_perm = DCCP_SOCKET__RECV_MSG;
break;
-
default:
netif_perm = NETIF__RAWIP_RECV;
node_perm = NODE__RAWIP_RECV;
+ recv_perm = 0;
break;
}
- err = avc_has_perm(sock_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
+ err = sel_netif_sid(skb->iif, &if_sid);
if (err)
- goto out;
-
- err = security_node_sid(family, addrp, len, &node_sid);
+ return err;
+ err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
if (err)
- goto out;
+ return err;
- err = avc_has_perm(sock_sid, node_sid, SECCLASS_NODE, node_perm, ad);
+ err = sel_netnode_sid(addrp, family, &node_sid);
if (err)
- goto out;
+ return err;
+ err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
+ if (err)
+ return err;
+
+ if (!recv_perm)
+ return 0;
+ err = security_port_sid(sk->sk_family, sk->sk_type,
+ sk->sk_protocol, ntohs(ad->u.net.sport),
+ &port_sid);
+ if (unlikely(err)) {
+ printk(KERN_WARNING
+ "SELinux: failure in"
+ " selinux_sock_rcv_skb_iptables_compat(),"
+ " network port label not found\n");
+ return err;
+ }
+ return avc_has_perm(sk_sid, port_sid, sk_class, recv_perm, ad);
+}
- if (recv_perm) {
- u32 port_sid;
+static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
+ struct avc_audit_data *ad,
+ u16 family, char *addrp)
+{
+ int err;
+ struct sk_security_struct *sksec = sk->sk_security;
+ u32 peer_sid;
+ u32 sk_sid = sksec->sid;
- err = security_port_sid(sk->sk_family, sk->sk_type,
- sk->sk_protocol, ntohs(ad->u.net.sport),
- &port_sid);
- if (err)
- goto out;
+ if (selinux_compat_net)
+ err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
+ family, addrp);
+ else
+ err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
+ PACKET__RECV, ad);
+ if (err)
+ return err;
- err = avc_has_perm(sock_sid, port_sid,
- sock_class, recv_perm, ad);
+ if (selinux_policycap_netpeer) {
+ err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
+ if (err)
+ return err;
+ err = avc_has_perm(sk_sid, peer_sid,
+ SECCLASS_PEER, PEER__RECV, ad);
+ } else {
+ err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
+ if (err)
+ return err;
+ err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
}
-out:
return err;
}
static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
- u16 family;
- char *addrp;
- int len, err = 0;
- struct avc_audit_data ad;
+ int err;
struct sk_security_struct *sksec = sk->sk_security;
+ u16 family = sk->sk_family;
+ u32 sk_sid = sksec->sid;
+ struct avc_audit_data ad;
+ char *addrp;
- family = sk->sk_family;
if (family != PF_INET && family != PF_INET6)
- goto out;
+ return 0;
/* Handle mapped IPv4 packets arriving via IPv6 sockets */
if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
family = PF_INET;
AVC_AUDIT_DATA_INIT(&ad, NET);
- ad.u.net.netif = skb->dev ? skb->dev->name : "[unknown]";
+ ad.u.net.netif = skb->iif;
ad.u.net.family = family;
-
- err = selinux_parse_skb(skb, &ad, &addrp, &len, 1, NULL);
+ err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
if (err)
- goto out;
+ return err;
- if (selinux_compat_net)
- err = selinux_sock_rcv_skb_compat(sk, skb, &ad, family,
- addrp, len);
- else
- err = avc_has_perm(sksec->sid, skb->secmark, SECCLASS_PACKET,
- PACKET__RECV, &ad);
- if (err)
- goto out;
+ /* If any sort of compatibility mode is enabled then handoff processing
+ * to the selinux_sock_rcv_skb_compat() function to deal with the
+ * special handling. We do this in an attempt to keep this function
+ * as fast and as clean as possible. */
+ if (selinux_compat_net || !selinux_policycap_netpeer)
+ return selinux_sock_rcv_skb_compat(sk, skb, &ad,
+ family, addrp);
- err = selinux_netlbl_sock_rcv_skb(sksec, skb, &ad);
- if (err)
- goto out;
+ if (netlbl_enabled() || selinux_xfrm_enabled()) {
+ u32 peer_sid;
+
+ err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
+ if (err)
+ return err;
+ err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
+ peer_sid, &ad);
+ if (err)
+ return err;
+ err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
+ PEER__RECV, &ad);
+ }
+
+ if (selinux_secmark_enabled()) {
+ err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
+ PACKET__RECV, &ad);
+ if (err)
+ return err;
+ }
- err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
-out:
return err;
}
@@ -3759,18 +4092,25 @@ out:
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
{
u32 peer_secid = SECSID_NULL;
- int err = 0;
+ u16 family;
+
+ if (sock)
+ family = sock->sk->sk_family;
+ else if (skb && skb->sk)
+ family = skb->sk->sk_family;
+ else
+ goto out;
- if (sock && sock->sk->sk_family == PF_UNIX)
+ if (sock && family == PF_UNIX)
selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid);
else if (skb)
- selinux_skb_extlbl_sid(skb, &peer_secid);
+ selinux_skb_peerlbl_sid(skb, family, &peer_secid);
- if (peer_secid == SECSID_NULL)
- err = -EINVAL;
+out:
*secid = peer_secid;
-
- return err;
+ if (peer_secid == SECSID_NULL)
+ return -EINVAL;
+ return 0;
}
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
@@ -3790,6 +4130,7 @@ static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
newssec->sid = ssec->sid;
newssec->peer_sid = ssec->peer_sid;
+ newssec->sclass = ssec->sclass;
selinux_netlbl_sk_security_clone(ssec, newssec);
}
@@ -3813,6 +4154,7 @@ static void selinux_sock_graft(struct sock* sk, struct socket *parent)
if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
sk->sk_family == PF_UNIX)
isec->sid = sksec->sid;
+ sksec->sclass = isec->sclass;
selinux_netlbl_sock_graft(sk, parent);
}
@@ -3825,7 +4167,9 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
u32 newsid;
u32 peersid;
- selinux_skb_extlbl_sid(skb, &peersid);
+ err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
+ if (err)
+ return err;
if (peersid == SECSID_NULL) {
req->secid = sksec->sid;
req->peer_secid = SECSID_NULL;
@@ -3863,7 +4207,7 @@ static void selinux_inet_conn_established(struct sock *sk,
{
struct sk_security_struct *sksec = sk->sk_security;
- selinux_skb_extlbl_sid(skb, &sksec->peer_sid);
+ selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
}
static void selinux_req_classify_flow(const struct request_sock *req,
@@ -3910,149 +4254,260 @@ out:
#ifdef CONFIG_NETFILTER
-static int selinux_ip_postroute_last_compat(struct sock *sk, struct net_device *dev,
- struct avc_audit_data *ad,
- u16 family, char *addrp, int len)
+static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
+ u16 family)
{
- int err = 0;
- u32 netif_perm, node_perm, node_sid, if_sid, send_perm = 0;
- struct socket *sock;
- struct inode *inode;
- struct inode_security_struct *isec;
+ char *addrp;
+ u32 peer_sid;
+ struct avc_audit_data ad;
+ u8 secmark_active;
+ u8 peerlbl_active;
- sock = sk->sk_socket;
- if (!sock)
- goto out;
+ if (!selinux_policycap_netpeer)
+ return NF_ACCEPT;
- inode = SOCK_INODE(sock);
- if (!inode)
- goto out;
+ secmark_active = selinux_secmark_enabled();
+ peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+ if (!secmark_active && !peerlbl_active)
+ return NF_ACCEPT;
- isec = inode->i_security;
-
- err = sel_netif_sids(dev, &if_sid, NULL);
- if (err)
- goto out;
+ AVC_AUDIT_DATA_INIT(&ad, NET);
+ ad.u.net.netif = ifindex;
+ ad.u.net.family = family;
+ if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
+ return NF_DROP;
+
+ if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
+ return NF_DROP;
+
+ if (peerlbl_active)
+ if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
+ peer_sid, &ad) != 0)
+ return NF_DROP;
+
+ if (secmark_active)
+ if (avc_has_perm(peer_sid, skb->secmark,
+ SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
+ return NF_DROP;
+
+ return NF_ACCEPT;
+}
- switch (isec->sclass) {
+static unsigned int selinux_ipv4_forward(unsigned int hooknum,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return selinux_ip_forward(skb, in->ifindex, PF_INET);
+}
+
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static unsigned int selinux_ipv6_forward(unsigned int hooknum,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return selinux_ip_forward(skb, in->ifindex, PF_INET6);
+}
+#endif /* IPV6 */
+
+static int selinux_ip_postroute_iptables_compat(struct sock *sk,
+ int ifindex,
+ struct avc_audit_data *ad,
+ u16 family, char *addrp)
+{
+ int err;
+ struct sk_security_struct *sksec = sk->sk_security;
+ u16 sk_class;
+ u32 netif_perm, node_perm, send_perm;
+ u32 port_sid, node_sid, if_sid, sk_sid;
+
+ sk_sid = sksec->sid;
+ sk_class = sksec->sclass;
+
+ switch (sk_class) {
case SECCLASS_UDP_SOCKET:
netif_perm = NETIF__UDP_SEND;
node_perm = NODE__UDP_SEND;
send_perm = UDP_SOCKET__SEND_MSG;
break;
-
case SECCLASS_TCP_SOCKET:
netif_perm = NETIF__TCP_SEND;
node_perm = NODE__TCP_SEND;
send_perm = TCP_SOCKET__SEND_MSG;
break;
-
case SECCLASS_DCCP_SOCKET:
netif_perm = NETIF__DCCP_SEND;
node_perm = NODE__DCCP_SEND;
send_perm = DCCP_SOCKET__SEND_MSG;
break;
-
default:
netif_perm = NETIF__RAWIP_SEND;
node_perm = NODE__RAWIP_SEND;
+ send_perm = 0;
break;
}
- err = avc_has_perm(isec->sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
+ err = sel_netif_sid(ifindex, &if_sid);
if (err)
- goto out;
+ return err;
+ err = avc_has_perm(sk_sid, if_sid, SECCLASS_NETIF, netif_perm, ad);
+ return err;
- err = security_node_sid(family, addrp, len, &node_sid);
+ err = sel_netnode_sid(addrp, family, &node_sid);
if (err)
- goto out;
-
- err = avc_has_perm(isec->sid, node_sid, SECCLASS_NODE, node_perm, ad);
+ return err;
+ err = avc_has_perm(sk_sid, node_sid, SECCLASS_NODE, node_perm, ad);
if (err)
- goto out;
+ return err;
- if (send_perm) {
- u32 port_sid;
-
- err = security_port_sid(sk->sk_family,
- sk->sk_type,
- sk->sk_protocol,
- ntohs(ad->u.net.dport),
- &port_sid);
- if (err)
- goto out;
+ if (send_perm != 0)
+ return 0;
- err = avc_has_perm(isec->sid, port_sid, isec->sclass,
- send_perm, ad);
+ err = security_port_sid(sk->sk_family, sk->sk_type,
+ sk->sk_protocol, ntohs(ad->u.net.dport),
+ &port_sid);
+ if (unlikely(err)) {
+ printk(KERN_WARNING
+ "SELinux: failure in"
+ " selinux_ip_postroute_iptables_compat(),"
+ " network port label not found\n");
+ return err;
}
-out:
- return err;
+ return avc_has_perm(sk_sid, port_sid, sk_class, send_perm, ad);
}
-static unsigned int selinux_ip_postroute_last(unsigned int hooknum,
- struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *),
- u16 family)
+static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
+ int ifindex,
+ struct avc_audit_data *ad,
+ u16 family,
+ char *addrp,
+ u8 proto)
{
- char *addrp;
- int len, err = 0;
- struct sock *sk;
- struct avc_audit_data ad;
- struct net_device *dev = (struct net_device *)out;
+ struct sock *sk = skb->sk;
struct sk_security_struct *sksec;
- u8 proto;
-
- sk = skb->sk;
- if (!sk)
- goto out;
+ if (sk == NULL)
+ return NF_ACCEPT;
sksec = sk->sk_security;
- AVC_AUDIT_DATA_INIT(&ad, NET);
- ad.u.net.netif = dev->name;
- ad.u.net.family = family;
+ if (selinux_compat_net) {
+ if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
+ ad, family, addrp))
+ return NF_DROP;
+ } else {
+ if (avc_has_perm(sksec->sid, skb->secmark,
+ SECCLASS_PACKET, PACKET__SEND, ad))
+ return NF_DROP;
+ }
- err = selinux_parse_skb(skb, &ad, &addrp, &len, 0, &proto);
- if (err)
- goto out;
+ if (selinux_policycap_netpeer)
+ if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
+ return NF_DROP;
- if (selinux_compat_net)
- err = selinux_ip_postroute_last_compat(sk, dev, &ad,
- family, addrp, len);
- else
- err = avc_has_perm(sksec->sid, skb->secmark, SECCLASS_PACKET,
- PACKET__SEND, &ad);
+ return NF_ACCEPT;
+}
- if (err)
- goto out;
+static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
+ u16 family)
+{
+ u32 secmark_perm;
+ u32 peer_sid;
+ struct sock *sk;
+ struct avc_audit_data ad;
+ char *addrp;
+ u8 proto;
+ u8 secmark_active;
+ u8 peerlbl_active;
- err = selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto);
-out:
- return err ? NF_DROP : NF_ACCEPT;
+ AVC_AUDIT_DATA_INIT(&ad, NET);
+ ad.u.net.netif = ifindex;
+ ad.u.net.family = family;
+ if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
+ return NF_DROP;
+
+ /* If any sort of compatibility mode is enabled then handoff processing
+ * to the selinux_ip_postroute_compat() function to deal with the
+ * special handling. We do this in an attempt to keep this function
+ * as fast and as clean as possible. */
+ if (selinux_compat_net || !selinux_policycap_netpeer)
+ return selinux_ip_postroute_compat(skb, ifindex, &ad,
+ family, addrp, proto);
+
+ /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
+ * packet transformation so allow the packet to pass without any checks
+ * since we'll have another chance to perform access control checks
+ * when the packet is on it's final way out.
+ * NOTE: there appear to be some IPv6 multicast cases where skb->dst
+ * is NULL, in this case go ahead and apply access control. */
+ if (skb->dst != NULL && skb->dst->xfrm != NULL)
+ return NF_ACCEPT;
+
+ secmark_active = selinux_secmark_enabled();
+ peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+ if (!secmark_active && !peerlbl_active)
+ return NF_ACCEPT;
+
+ /* if the packet is locally generated (skb->sk != NULL) then use the
+ * socket's label as the peer label, otherwise the packet is being
+ * forwarded through this system and we need to fetch the peer label
+ * directly from the packet */
+ sk = skb->sk;
+ if (sk) {
+ struct sk_security_struct *sksec = sk->sk_security;
+ peer_sid = sksec->sid;
+ secmark_perm = PACKET__SEND;
+ } else {
+ if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
+ return NF_DROP;
+ secmark_perm = PACKET__FORWARD_OUT;
+ }
+
+ if (secmark_active)
+ if (avc_has_perm(peer_sid, skb->secmark,
+ SECCLASS_PACKET, secmark_perm, &ad))
+ return NF_DROP;
+
+ if (peerlbl_active) {
+ u32 if_sid;
+ u32 node_sid;
+
+ if (sel_netif_sid(ifindex, &if_sid))
+ return NF_DROP;
+ if (avc_has_perm(peer_sid, if_sid,
+ SECCLASS_NETIF, NETIF__EGRESS, &ad))
+ return NF_DROP;
+
+ if (sel_netnode_sid(addrp, family, &node_sid))
+ return NF_DROP;
+ if (avc_has_perm(peer_sid, node_sid,
+ SECCLASS_NODE, NODE__SENDTO, &ad))
+ return NF_DROP;
+ }
+
+ return NF_ACCEPT;
}
-static unsigned int selinux_ipv4_postroute_last(unsigned int hooknum,
- struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *))
+static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
{
- return selinux_ip_postroute_last(hooknum, skb, in, out, okfn, PF_INET);
+ return selinux_ip_postroute(skb, out->ifindex, PF_INET);
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-
-static unsigned int selinux_ipv6_postroute_last(unsigned int hooknum,
- struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *))
+static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
{
- return selinux_ip_postroute_last(hooknum, skb, in, out, okfn, PF_INET6);
+ return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
}
-
#endif /* IPV6 */
#endif /* CONFIG_NETFILTER */
@@ -4710,6 +5165,11 @@ static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
return security_sid_to_context(secid, secdata, seclen);
}
+static int selinux_secctx_to_secid(char *secdata, u32 seclen, u32 *secid)
+{
+ return security_context_to_sid(secdata, seclen, secid);
+}
+
static void selinux_release_secctx(char *secdata, u32 seclen)
{
kfree(secdata);
@@ -4800,6 +5260,11 @@ static struct security_operations selinux_ops = {
.sb_statfs = selinux_sb_statfs,
.sb_mount = selinux_mount,
.sb_umount = selinux_umount,
+ .sb_get_mnt_opts = selinux_get_mnt_opts,
+ .sb_set_mnt_opts = selinux_set_mnt_opts,
+ .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
+ .sb_parse_opts_str = selinux_parse_opts_str,
+
.inode_alloc_security = selinux_inode_alloc_security,
.inode_free_security = selinux_inode_free_security,
@@ -4898,6 +5363,7 @@ static struct security_operations selinux_ops = {
.setprocattr = selinux_setprocattr,
.secid_to_secctx = selinux_secid_to_secctx,
+ .secctx_to_secid = selinux_secctx_to_secid,
.release_secctx = selinux_release_secctx,
.unix_stream_connect = selinux_socket_unix_stream_connect,
@@ -5031,22 +5497,40 @@ security_initcall(selinux_init);
#if defined(CONFIG_NETFILTER)
-static struct nf_hook_ops selinux_ipv4_op = {
- .hook = selinux_ipv4_postroute_last,
- .owner = THIS_MODULE,
- .pf = PF_INET,
- .hooknum = NF_IP_POST_ROUTING,
- .priority = NF_IP_PRI_SELINUX_LAST,
+static struct nf_hook_ops selinux_ipv4_ops[] = {
+ {
+ .hook = selinux_ipv4_postroute,
+ .owner = THIS_MODULE,
+ .pf = PF_INET,
+ .hooknum = NF_INET_POST_ROUTING,
+ .priority = NF_IP_PRI_SELINUX_LAST,
+ },
+ {
+ .hook = selinux_ipv4_forward,
+ .owner = THIS_MODULE,
+ .pf = PF_INET,
+ .hooknum = NF_INET_FORWARD,
+ .priority = NF_IP_PRI_SELINUX_FIRST,
+ }
};
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static struct nf_hook_ops selinux_ipv6_op = {
- .hook = selinux_ipv6_postroute_last,
- .owner = THIS_MODULE,
- .pf = PF_INET6,
- .hooknum = NF_IP6_POST_ROUTING,
- .priority = NF_IP6_PRI_SELINUX_LAST,
+static struct nf_hook_ops selinux_ipv6_ops[] = {
+ {
+ .hook = selinux_ipv6_postroute,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_INET_POST_ROUTING,
+ .priority = NF_IP6_PRI_SELINUX_LAST,
+ },
+ {
+ .hook = selinux_ipv6_forward,
+ .owner = THIS_MODULE,
+ .pf = PF_INET6,
+ .hooknum = NF_INET_FORWARD,
+ .priority = NF_IP6_PRI_SELINUX_FIRST,
+ }
};
#endif /* IPV6 */
@@ -5054,22 +5538,27 @@ static struct nf_hook_ops selinux_ipv6_op = {
static int __init selinux_nf_ip_init(void)
{
int err = 0;
+ u32 iter;
if (!selinux_enabled)
goto out;
printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
- err = nf_register_hook(&selinux_ipv4_op);
- if (err)
- panic("SELinux: nf_register_hook for IPv4: error %d\n", err);
+ for (iter = 0; iter < ARRAY_SIZE(selinux_ipv4_ops); iter++) {
+ err = nf_register_hook(&selinux_ipv4_ops[iter]);
+ if (err)
+ panic("SELinux: nf_register_hook for IPv4: error %d\n",
+ err);
+ }
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-
- err = nf_register_hook(&selinux_ipv6_op);
- if (err)
- panic("SELinux: nf_register_hook for IPv6: error %d\n", err);
-
+ for (iter = 0; iter < ARRAY_SIZE(selinux_ipv6_ops); iter++) {
+ err = nf_register_hook(&selinux_ipv6_ops[iter]);
+ if (err)
+ panic("SELinux: nf_register_hook for IPv6: error %d\n",
+ err);
+ }
#endif /* IPV6 */
out:
@@ -5081,11 +5570,15 @@ __initcall(selinux_nf_ip_init);
#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
+ u32 iter;
+
printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
- nf_unregister_hook(&selinux_ipv4_op);
+ for (iter = 0; iter < ARRAY_SIZE(selinux_ipv4_ops); iter++)
+ nf_unregister_hook(&selinux_ipv4_ops[iter]);
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- nf_unregister_hook(&selinux_ipv6_op);
+ for (iter = 0; iter < ARRAY_SIZE(selinux_ipv6_ops); iter++)
+ nf_unregister_hook(&selinux_ipv6_ops[iter]);
#endif /* IPV6 */
}
#endif
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