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  1. 15 2月, 2008 2 次提交
  3. 14 2月, 2008 1 次提交
  5. 11 2月, 2008 1 次提交
  7. 08 2月, 2008 1 次提交
  9. 06 2月, 2008 7 次提交
    • P
      SELinux: Remove security_get_policycaps() · 394c6753
      由 Paul Moore 提交于 
      The security_get_policycaps() functions has a couple of bugs in it and it
isn't currently used by any in-tree code, so get rid of it and all of it's
bugginess.
Signed-off-by: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames Morris <jmorris@localhost.localdomain>
      394c6753
    • E
      security: allow Kconfig to set default mmap_min_addr protection · a5ecbcb8
      由 Eric Paris 提交于 
      Since it was decided that low memory protection from userspace couldn't
be turned on by default add a Kconfig option to allow users/distros to
set a default at compile time.  This value is still tunable after boot
in /proc/sys/vm/mmap_min_addr

Discussion:
http://www.mail-archive.com/linux-security-module@vger.kernel.org/msg02543.htmlSigned-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NJames Morris <jmorris@namei.org>
      a5ecbcb8
    • C
      Smack: Simplified Mandatory Access Control Kernel · e114e473
      由 Casey Schaufler 提交于 
      Smack is the Simplified Mandatory Access Control Kernel.

Smack implements mandatory access control (MAC) using labels
attached to tasks and data containers, including files, SVIPC,
and other tasks. Smack is a kernel based scheme that requires
an absolute minimum of application support and a very small
amount of configuration data.

Smack uses extended attributes and
provides a set of general mount options, borrowing technics used
elsewhere. Smack uses netlabel for CIPSO labeling. Smack provides
a pseudo-filesystem smackfs that is used for manipulation of
system Smack attributes.

The patch, patches for ls and sshd, a README, a startup script,
and x86 binaries for ls and sshd are also available on

    http://www.schaufler-ca.com

Development has been done using Fedora Core 7 in a virtual machine
environment and on an old Sony laptop.

Smack provides mandatory access controls based on the label attached
to a task and the label attached to the object it is attempting to
access. Smack labels are deliberately short (1-23 characters) text
strings. Single character labels using special characters are reserved
for system use. The only operation applied to Smack labels is equality
comparison. No wildcards or expressions, regular or otherwise, are
used. Smack labels are composed of printable characters and may not
include "/".

A file always gets the Smack label of the task that created it.

Smack defines and uses these labels:

    "*" - pronounced "star"
    "_" - pronounced "floor"
    "^" - pronounced "hat"
    "?" - pronounced "huh"

The access rules enforced by Smack are, in order:

1. Any access requested by a task labeled "*" is denied.
2. A read or execute access requested by a task labeled "^"
   is permitted.
3. A read or execute access requested on an object labeled "_"
   is permitted.
4. Any access requested on an object labeled "*" is permitted.
5. Any access requested by a task on an object with the same
   label is permitted.
6. Any access requested that is explicitly defined in the loaded
   rule set is permitted.
7. Any other access is denied.

Rules may be explicitly defined by writing subject,object,access
triples to /smack/load.

Smack rule sets can be easily defined that describe Bell&LaPadula
sensitivity, Biba integrity, and a variety of interesting
configurations. Smack rule sets can be modified on the fly to
accommodate changes in the operating environment or even the time
of day.

Some practical use cases:

Hierarchical levels. The less common of the two usual uses
for MLS systems is to define hierarchical levels, often
unclassified, confidential, secret, and so on. To set up smack
to support this, these rules could be defined:

   C        Unclass rx
   S        C       rx
   S        Unclass rx
   TS       S       rx
   TS       C       rx
   TS       Unclass rx

A TS process can read S, C, and Unclass data, but cannot write it.
An S process can read C and Unclass. Note that specifying that
TS can read S and S can read C does not imply TS can read C, it
has to be explicitly stated.

Non-hierarchical categories. This is the more common of the
usual uses for an MLS system. Since the default rule is that a
subject cannot access an object with a different label no
access rules are required to implement compartmentalization.

A case that the Bell & LaPadula policy does not allow is demonstrated
with this Smack access rule:

A case that Bell&LaPadula does not allow that Smack does:

    ESPN    ABC   r
    ABC     ESPN  r

On my portable video device I have two applications, one that
shows ABC programming and the other ESPN programming. ESPN wants
to show me sport stories that show up as news, and ABC will
only provide minimal information about a sports story if ESPN
is covering it. Each side can look at the other's info, neither
can change the other. Neither can see what FOX is up to, which
is just as well all things considered.

Another case that I especially like:

    SatData Guard   w
    Guard   Publish w

A program running with the Guard label opens a UDP socket and
accepts messages sent by a program running with a SatData label.
The Guard program inspects the message to ensure it is wholesome
and if it is sends it to a program running with the Publish label.
This program then puts the information passed in an appropriate
place. Note that the Guard program cannot write to a Publish
file system object because file system semanitic require read as
well as write.

The four cases (categories, levels, mutual read, guardbox) here
are all quite real, and problems I've been asked to solve over
the years. The first two are easy to do with traditonal MLS systems
while the last two you can't without invoking privilege, at least
for a while.
Signed-off-by: NCasey Schaufler <casey@schaufler-ca.com>
Cc: Joshua Brindle <method@manicmethod.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: "Ahmed S. Darwish" <darwish.07@gmail.com>
Cc: Andrew G. Morgan <morgan@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e114e473
    • S
      capabilities: introduce per-process capability bounding set · 3b7391de
      由 Serge E. Hallyn 提交于 
      The capability bounding set is a set beyond which capabilities cannot grow.
 Currently cap_bset is per-system.  It can be manipulated through sysctl,
but only init can add capabilities.  Root can remove capabilities.  By
default it includes all caps except CAP_SETPCAP.

This patch makes the bounding set per-process when file capabilities are
enabled.  It is inherited at fork from parent.  Noone can add elements,
CAP_SETPCAP is required to remove them.

One example use of this is to start a safer container.  For instance, until
device namespaces or per-container device whitelists are introduced, it is
best to take CAP_MKNOD away from a container.

The bounding set will not affect pP and pE immediately.  It will only
affect pP' and pE' after subsequent exec()s.  It also does not affect pI,
and exec() does not constrain pI'.  So to really start a shell with no way
of regain CAP_MKNOD, you would do

	prctl(PR_CAPBSET_DROP, CAP_MKNOD);
	cap_t cap = cap_get_proc();
	cap_value_t caparray[1];
	caparray[0] = CAP_MKNOD;
	cap_set_flag(cap, CAP_INHERITABLE, 1, caparray, CAP_DROP);
	cap_set_proc(cap);
	cap_free(cap);

The following test program will get and set the bounding
set (but not pI).  For instance

	./bset get
		(lists capabilities in bset)
	./bset drop cap_net_raw
		(starts shell with new bset)
		(use capset, setuid binary, or binary with
		file capabilities to try to increase caps)

************************************************************
cap_bound.c
************************************************************
 #include <sys/prctl.h>
 #include <linux/capability.h>
 #include <sys/types.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #ifndef PR_CAPBSET_READ
 #define PR_CAPBSET_READ 23
 #endif

 #ifndef PR_CAPBSET_DROP
 #define PR_CAPBSET_DROP 24
 #endif

int usage(char *me)
{
	printf("Usage: %s get\n", me);
	printf("       %s drop <capability>\n", me);
	return 1;
}

 #define numcaps 32
char *captable[numcaps] = {
	"cap_chown",
	"cap_dac_override",
	"cap_dac_read_search",
	"cap_fowner",
	"cap_fsetid",
	"cap_kill",
	"cap_setgid",
	"cap_setuid",
	"cap_setpcap",
	"cap_linux_immutable",
	"cap_net_bind_service",
	"cap_net_broadcast",
	"cap_net_admin",
	"cap_net_raw",
	"cap_ipc_lock",
	"cap_ipc_owner",
	"cap_sys_module",
	"cap_sys_rawio",
	"cap_sys_chroot",
	"cap_sys_ptrace",
	"cap_sys_pacct",
	"cap_sys_admin",
	"cap_sys_boot",
	"cap_sys_nice",
	"cap_sys_resource",
	"cap_sys_time",
	"cap_sys_tty_config",
	"cap_mknod",
	"cap_lease",
	"cap_audit_write",
	"cap_audit_control",
	"cap_setfcap"
};

int getbcap(void)
{
	int comma=0;
	unsigned long i;
	int ret;

	printf("i know of %d capabilities\n", numcaps);
	printf("capability bounding set:");
	for (i=0; i<numcaps; i++) {
		ret = prctl(PR_CAPBSET_READ, i);
		if (ret < 0)
			perror("prctl");
		else if (ret==1)
			printf("%s%s", (comma++) ? ", " : " ", captable[i]);
	}
	printf("\n");
	return 0;
}

int capdrop(char *str)
{
	unsigned long i;

	int found=0;
	for (i=0; i<numcaps; i++) {
		if (strcmp(captable[i], str) == 0) {
			found=1;
			break;
		}
	}
	if (!found)
		return 1;
	if (prctl(PR_CAPBSET_DROP, i)) {
		perror("prctl");
		return 1;
	}
	return 0;
}

int main(int argc, char *argv[])
{
	if (argc<2)
		return usage(argv[0]);
	if (strcmp(argv[1], "get")==0)
		return getbcap();
	if (strcmp(argv[1], "drop")!=0 || argc<3)
		return usage(argv[0]);
	if (capdrop(argv[2])) {
		printf("unknown capability\n");
		return 1;
	}
	return execl("/bin/bash", "/bin/bash", NULL);
}
************************************************************

[serue@us.ibm.com: fix typo]
Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>a
Signed-off-by: N"Serge E. Hallyn" <serue@us.ibm.com>
Tested-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3b7391de
    • A
      Add 64-bit capability support to the kernel · e338d263
      由 Andrew Morgan 提交于 
      The patch supports legacy (32-bit) capability userspace, and where possible
translates 32-bit capabilities to/from userspace and the VFS to 64-bit
kernel space capabilities.  If a capability set cannot be compressed into
32-bits for consumption by user space, the system call fails, with -ERANGE.

FWIW libcap-2.00 supports this change (and earlier capability formats)

 http://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/

[akpm@linux-foundation.org: coding-syle fixes]
[akpm@linux-foundation.org: use get_task_comm()]
[ezk@cs.sunysb.edu: build fix]
[akpm@linux-foundation.org: do not initialise statics to 0 or NULL]
[akpm@linux-foundation.org: unused var]
[serue@us.ibm.com: export __cap_ symbols]
Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: NErez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e338d263
    • A
      revert "capabilities: clean up file capability reading" · 8f6936f4
      由 Andrew Morton 提交于 
      Revert b68680e4 to make way for the next
patch: "Add 64-bit capability support to the kernel".

We want to keep the vfs_cap_data.data[] structure, using two 'data's for
64-bit caps (and later three for 96-bit caps), whereas
b68680e4 had gotten rid of the 'data' struct
made its members inline.

The 64-bit caps patch keeps the stack abuse fix at get_file_caps(), which was
the more important part of that patch.

[akpm@linux-foundation.org: coding-style fixes]
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: James Morris <jmorris@namei.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Andrew Morgan <morgan@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8f6936f4
    • D
      VFS/Security: Rework inode_getsecurity and callers to return resulting buffer · 42492594
      由 David P. Quigley 提交于 
      This patch modifies the interface to inode_getsecurity to have the function
return a buffer containing the security blob and its length via parameters
instead of relying on the calling function to give it an appropriately sized
buffer.

Security blobs obtained with this function should be freed using the
release_secctx LSM hook.  This alleviates the problem of the caller having to
guess a length and preallocate a buffer for this function allowing it to be
used elsewhere for Labeled NFS.

The patch also removed the unused err parameter.  The conversion is similar to
the one performed by Al Viro for the security_getprocattr hook.
Signed-off-by: NDavid P. Quigley <dpquigl@tycho.nsa.gov>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Chris Wright <chrisw@sous-sol.org>
Acked-by: NJames Morris <jmorris@namei.org>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      42492594
  11. 02 2月, 2008 2 次提交
  13. 01 2月, 2008 1 次提交
  15. 30 1月, 2008 14 次提交
  17. 29 1月, 2008 1 次提交
  19. 26 1月, 2008 1 次提交
  21. 25 1月, 2008 9 次提交