+ Features

- add support for mapping secids and using secctxes
   - add the ability to get a task's secid
   - add support for audit rule filtering
 
 + Cleanups
   - multiple typo fixes
   - Convert to use match_string() helper
   - update git and wiki locations in AppArmor docs
   - improve get_buffers macro by using get_cpu_ptr
   - Use an IDR to allocate apparmor secids
 
 + Bug fixes
   - fix '*seclen' is never less than zero
   - fix mediation of prlimit
   - fix memory leak when deduping profile load
   - fix ptrace read check
   - fix memory leak of rule on error exit path
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Merge tag 'apparmor-pr-2018-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull AppArmor updates from John Johansen:
 "Features
   - add support for mapping secids and using secctxes
   - add the ability to get a task's secid
   - add support for audit rule filtering

  Cleanups:
   - multiple typo fixes
   - Convert to use match_string() helper
   - update git and wiki locations in AppArmor docs
   - improve get_buffers macro by using get_cpu_ptr
   - Use an IDR to allocate apparmor secids

  Bug fixes:
   - fix '*seclen' is never less than zero
   - fix mediation of prlimit
   - fix memory leak when deduping profile load
   - fix ptrace read check
   - fix memory leak of rule on error exit path"

* tag 'apparmor-pr-2018-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (21 commits)
  apparmor: fix ptrace read check
  apparmor: fix memory leak when deduping profile load
  apparmor: fix mediation of prlimit
  apparmor: fixup secid map conversion to using IDR
  apparmor: Use an IDR to allocate apparmor secids
  apparmor: Fix memory leak of rule on error exit path
  apparmor: modify audit rule support to support profile stacks
  apparmor: Add support for audit rule filtering
  apparmor: update git and wiki locations in AppArmor docs
  apparmor: Convert to use match_string() helper
  apparmor: improve get_buffers macro by using get_cpu_ptr
  apparmor: fix '*seclen' is never less than zero
  apparmor: fix typo "preconfinement"
  apparmor: fix typo "independent"
  apparmor: fix typo "traverse"
  apparmor: fix typo "type"
  apparmor: fix typo "replace"
  apparmor: fix typo "comparison"
  apparmor: fix typo "loosen"
  apparmor: add the ability to get a task's secid
  ...
This commit is contained in:
Linus Torvalds 2018-06-14 16:11:28 +09:00
commit 463f202172
15 changed files with 313 additions and 74 deletions

View File

@ -44,8 +44,8 @@ Links
Mailing List - apparmor@lists.ubuntu.com Mailing List - apparmor@lists.ubuntu.com
Wiki - http://apparmor.wiki.kernel.org/ Wiki - http://wiki.apparmor.net
User space tools - https://launchpad.net/apparmor User space tools - https://gitlab.com/apparmor
Kernel module - git://git.kernel.org/pub/scm/linux/kernel/git/jj/apparmor-dev.git Kernel module - git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

View File

@ -19,7 +19,7 @@
#include "include/audit.h" #include "include/audit.h"
#include "include/policy.h" #include "include/policy.h"
#include "include/policy_ns.h" #include "include/policy_ns.h"
#include "include/secid.h"
const char *const audit_mode_names[] = { const char *const audit_mode_names[] = {
"normal", "normal",
@ -163,3 +163,91 @@ int aa_audit(int type, struct aa_profile *profile, struct common_audit_data *sa,
return aad(sa)->error; return aad(sa)->error;
} }
struct aa_audit_rule {
struct aa_label *label;
};
void aa_audit_rule_free(void *vrule)
{
struct aa_audit_rule *rule = vrule;
if (rule) {
if (!IS_ERR(rule->label))
aa_put_label(rule->label);
kfree(rule);
}
}
int aa_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
{
struct aa_audit_rule *rule;
switch (field) {
case AUDIT_SUBJ_ROLE:
if (op != Audit_equal && op != Audit_not_equal)
return -EINVAL;
break;
default:
return -EINVAL;
}
rule = kzalloc(sizeof(struct aa_audit_rule), GFP_KERNEL);
if (!rule)
return -ENOMEM;
/* Currently rules are treated as coming from the root ns */
rule->label = aa_label_parse(&root_ns->unconfined->label, rulestr,
GFP_KERNEL, true, false);
if (IS_ERR(rule->label)) {
aa_audit_rule_free(rule);
return PTR_ERR(rule->label);
}
*vrule = rule;
return 0;
}
int aa_audit_rule_known(struct audit_krule *rule)
{
int i;
for (i = 0; i < rule->field_count; i++) {
struct audit_field *f = &rule->fields[i];
switch (f->type) {
case AUDIT_SUBJ_ROLE:
return 1;
}
}
return 0;
}
int aa_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
struct audit_context *actx)
{
struct aa_audit_rule *rule = vrule;
struct aa_label *label;
int found = 0;
label = aa_secid_to_label(sid);
if (!label)
return -ENOENT;
if (aa_label_is_subset(label, rule->label))
found = 1;
switch (field) {
case AUDIT_SUBJ_ROLE:
switch (op) {
case Audit_equal:
return found;
case Audit_not_equal:
return !found;
}
}
return 0;
}

View File

@ -839,7 +839,7 @@ static struct aa_label *handle_onexec(struct aa_label *label,
cond, unsafe)); cond, unsafe));
} else { } else {
/* TODO: determine how much we want to losen this */ /* TODO: determine how much we want to loosen this */
error = fn_for_each_in_ns(label, profile, error = fn_for_each_in_ns(label, profile,
profile_onexec(profile, onexec, stack, bprm, profile_onexec(profile, onexec, stack, bprm,
buffer, cond, unsafe)); buffer, cond, unsafe));

View File

@ -189,4 +189,10 @@ static inline int complain_error(int error)
return error; return error;
} }
void aa_audit_rule_free(void *vrule);
int aa_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule);
int aa_audit_rule_known(struct audit_krule *rule);
int aa_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
struct audit_context *actx);
#endif /* __AA_AUDIT_H */ #endif /* __AA_AUDIT_H */

View File

@ -281,7 +281,7 @@ void __aa_labelset_update_subtree(struct aa_ns *ns);
void aa_label_free(struct aa_label *label); void aa_label_free(struct aa_label *label);
void aa_label_kref(struct kref *kref); void aa_label_kref(struct kref *kref);
bool aa_label_init(struct aa_label *label, int size); bool aa_label_init(struct aa_label *label, int size, gfp_t gfp);
struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp); struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp);
bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub); bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub);

View File

@ -43,10 +43,11 @@ struct aa_buffers {
DECLARE_PER_CPU(struct aa_buffers, aa_buffers); DECLARE_PER_CPU(struct aa_buffers, aa_buffers);
#define ASSIGN(FN, X, N) ((X) = FN(N)) #define ASSIGN(FN, A, X, N) ((X) = FN(A, N))
#define EVAL1(FN, X) ASSIGN(FN, X, 0) /*X = FN(0)*/ #define EVAL1(FN, A, X) ASSIGN(FN, A, X, 0) /*X = FN(0)*/
#define EVAL2(FN, X, Y...) do { ASSIGN(FN, X, 1); EVAL1(FN, Y); } while (0) #define EVAL2(FN, A, X, Y...) \
#define EVAL(FN, X...) CONCATENATE(EVAL, COUNT_ARGS(X))(FN, X) do { ASSIGN(FN, A, X, 1); EVAL1(FN, A, Y); } while (0)
#define EVAL(FN, A, X...) CONCATENATE(EVAL, COUNT_ARGS(X))(FN, A, X)
#define for_each_cpu_buffer(I) for ((I) = 0; (I) < MAX_PATH_BUFFERS; (I)++) #define for_each_cpu_buffer(I) for ((I) = 0; (I) < MAX_PATH_BUFFERS; (I)++)
@ -56,26 +57,24 @@ DECLARE_PER_CPU(struct aa_buffers, aa_buffers);
#define AA_BUG_PREEMPT_ENABLED(X) /* nop */ #define AA_BUG_PREEMPT_ENABLED(X) /* nop */
#endif #endif
#define __get_buffer(N) ({ \ #define __get_buffer(C, N) ({ \
struct aa_buffers *__cpu_var; \
AA_BUG_PREEMPT_ENABLED("__get_buffer without preempt disabled"); \ AA_BUG_PREEMPT_ENABLED("__get_buffer without preempt disabled"); \
__cpu_var = this_cpu_ptr(&aa_buffers); \ (C)->buf[(N)]; })
__cpu_var->buf[(N)]; })
#define __get_buffers(X...) EVAL(__get_buffer, X) #define __get_buffers(C, X...) EVAL(__get_buffer, C, X)
#define __put_buffers(X, Y...) ((void)&(X)) #define __put_buffers(X, Y...) ((void)&(X))
#define get_buffers(X...) \ #define get_buffers(X...) \
do { \ do { \
preempt_disable(); \ struct aa_buffers *__cpu_var = get_cpu_ptr(&aa_buffers); \
__get_buffers(X); \ __get_buffers(__cpu_var, X); \
} while (0) } while (0)
#define put_buffers(X, Y...) \ #define put_buffers(X, Y...) \
do { \ do { \
__put_buffers(X, Y); \ __put_buffers(X, Y); \
preempt_enable(); \ put_cpu_ptr(&aa_buffers); \
} while (0) } while (0)
#endif /* __AA_PATH_H */ #endif /* __AA_PATH_H */

View File

@ -3,7 +3,7 @@
* *
* This file contains AppArmor security identifier (secid) definitions * This file contains AppArmor security identifier (secid) definitions
* *
* Copyright 2009-2010 Canonical Ltd. * Copyright 2009-2018 Canonical Ltd.
* *
* This program is free software; you can redistribute it and/or * This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as * modify it under the terms of the GNU General Public License as
@ -14,13 +14,24 @@
#ifndef __AA_SECID_H #ifndef __AA_SECID_H
#define __AA_SECID_H #define __AA_SECID_H
#include <linux/slab.h>
#include <linux/types.h> #include <linux/types.h>
struct aa_label;
/* secid value that will not be allocated */ /* secid value that will not be allocated */
#define AA_SECID_INVALID 0 #define AA_SECID_INVALID 0
#define AA_SECID_ALLOC AA_SECID_INVALID
u32 aa_alloc_secid(void); struct aa_label *aa_secid_to_label(u32 secid);
int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
void apparmor_release_secctx(char *secdata, u32 seclen);
int aa_alloc_secid(struct aa_label *label, gfp_t gfp);
void aa_free_secid(u32 secid); void aa_free_secid(u32 secid);
void aa_secid_update(u32 secid, struct aa_label *label);
void aa_secids_init(void);
#endif /* __AA_SECID_H */ #endif /* __AA_SECID_H */

View File

@ -128,7 +128,7 @@ static int ns_cmp(struct aa_ns *a, struct aa_ns *b)
} }
/** /**
* profile_cmp - profile comparision for set ordering * profile_cmp - profile comparison for set ordering
* @a: profile to compare (NOT NULL) * @a: profile to compare (NOT NULL)
* @b: profile to compare (NOT NULL) * @b: profile to compare (NOT NULL)
* *
@ -157,7 +157,7 @@ static int profile_cmp(struct aa_profile *a, struct aa_profile *b)
} }
/** /**
* vec_cmp - label comparision for set ordering * vec_cmp - label comparison for set ordering
* @a: label to compare (NOT NULL) * @a: label to compare (NOT NULL)
* @vec: vector of profiles to compare (NOT NULL) * @vec: vector of profiles to compare (NOT NULL)
* @n: length of @vec * @n: length of @vec
@ -402,13 +402,12 @@ static void label_free_or_put_new(struct aa_label *label, struct aa_label *new)
aa_put_label(new); aa_put_label(new);
} }
bool aa_label_init(struct aa_label *label, int size) bool aa_label_init(struct aa_label *label, int size, gfp_t gfp)
{ {
AA_BUG(!label); AA_BUG(!label);
AA_BUG(size < 1); AA_BUG(size < 1);
label->secid = aa_alloc_secid(); if (aa_alloc_secid(label, gfp) < 0)
if (label->secid == AA_SECID_INVALID)
return false; return false;
label->size = size; /* doesn't include null */ label->size = size; /* doesn't include null */
@ -441,7 +440,7 @@ struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp)
if (!new) if (!new)
goto fail; goto fail;
if (!aa_label_init(new, size)) if (!aa_label_init(new, size, gfp))
goto fail; goto fail;
if (!proxy) { if (!proxy) {
@ -463,7 +462,7 @@ fail:
/** /**
* label_cmp - label comparision for set ordering * label_cmp - label comparison for set ordering
* @a: label to compare (NOT NULL) * @a: label to compare (NOT NULL)
* @b: label to compare (NOT NULL) * @b: label to compare (NOT NULL)
* *
@ -2011,7 +2010,7 @@ out:
/** /**
* __label_update - insert updated version of @label into labelset * __label_update - insert updated version of @label into labelset
* @label - the label to update/repace * @label - the label to update/replace
* *
* Returns: new label that is up to date * Returns: new label that is up to date
* else NULL on failure * else NULL on failure

View File

@ -408,7 +408,7 @@ int aa_profile_label_perm(struct aa_profile *profile, struct aa_profile *target,
* @request: requested perms * @request: requested perms
* @deny: Returns: explicit deny set * @deny: Returns: explicit deny set
* @sa: initialized audit structure (MAY BE NULL if not auditing) * @sa: initialized audit structure (MAY BE NULL if not auditing)
* @cb: callback fn for tpye specific fields (MAY BE NULL) * @cb: callback fn for type specific fields (MAY BE NULL)
* *
* Returns: 0 if permission else error code * Returns: 0 if permission else error code
* *

View File

@ -39,6 +39,7 @@
#include "include/policy_ns.h" #include "include/policy_ns.h"
#include "include/procattr.h" #include "include/procattr.h"
#include "include/mount.h" #include "include/mount.h"
#include "include/secid.h"
/* Flag indicating whether initialization completed */ /* Flag indicating whether initialization completed */
int apparmor_initialized; int apparmor_initialized;
@ -116,7 +117,8 @@ static int apparmor_ptrace_access_check(struct task_struct *child,
tracer = begin_current_label_crit_section(); tracer = begin_current_label_crit_section();
tracee = aa_get_task_label(child); tracee = aa_get_task_label(child);
error = aa_may_ptrace(tracer, tracee, error = aa_may_ptrace(tracer, tracee,
mode == PTRACE_MODE_READ ? AA_PTRACE_READ : AA_PTRACE_TRACE); (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
: AA_PTRACE_TRACE);
aa_put_label(tracee); aa_put_label(tracee);
end_current_label_crit_section(tracer); end_current_label_crit_section(tracer);
@ -710,6 +712,13 @@ static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
return; return;
} }
static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
{
struct aa_label *label = aa_get_task_label(p);
*secid = label->secid;
aa_put_label(label);
}
static int apparmor_task_setrlimit(struct task_struct *task, static int apparmor_task_setrlimit(struct task_struct *task,
unsigned int resource, struct rlimit *new_rlim) unsigned int resource, struct rlimit *new_rlim)
{ {
@ -1186,8 +1195,20 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(task_free, apparmor_task_free), LSM_HOOK_INIT(task_free, apparmor_task_free),
LSM_HOOK_INIT(task_alloc, apparmor_task_alloc), LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit), LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
LSM_HOOK_INIT(task_kill, apparmor_task_kill), LSM_HOOK_INIT(task_kill, apparmor_task_kill),
#ifdef CONFIG_AUDIT
LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
#endif
LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
}; };
/* /*
@ -1378,14 +1399,12 @@ static int param_set_audit(const char *val, const struct kernel_param *kp)
if (apparmor_initialized && !policy_admin_capable(NULL)) if (apparmor_initialized && !policy_admin_capable(NULL))
return -EPERM; return -EPERM;
for (i = 0; i < AUDIT_MAX_INDEX; i++) { i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
if (strcmp(val, audit_mode_names[i]) == 0) { if (i < 0)
aa_g_audit = i; return -EINVAL;
return 0;
}
}
return -EINVAL; aa_g_audit = i;
return 0;
} }
static int param_get_mode(char *buffer, const struct kernel_param *kp) static int param_get_mode(char *buffer, const struct kernel_param *kp)
@ -1409,14 +1428,13 @@ static int param_set_mode(const char *val, const struct kernel_param *kp)
if (apparmor_initialized && !policy_admin_capable(NULL)) if (apparmor_initialized && !policy_admin_capable(NULL))
return -EPERM; return -EPERM;
for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) { i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
if (strcmp(val, aa_profile_mode_names[i]) == 0) { val);
aa_g_profile_mode = i; if (i < 0)
return 0; return -EINVAL;
}
}
return -EINVAL; aa_g_profile_mode = i;
return 0;
} }
/* /*
@ -1530,6 +1548,8 @@ static int __init apparmor_init(void)
return 0; return 0;
} }
aa_secids_init();
error = aa_setup_dfa_engine(); error = aa_setup_dfa_engine();
if (error) { if (error) {
AA_ERROR("Unable to setup dfa engine\n"); AA_ERROR("Unable to setup dfa engine\n");

View File

@ -472,7 +472,7 @@ unsigned int aa_dfa_match(struct aa_dfa *dfa, unsigned int start,
/** /**
* aa_dfa_next - step one character to the next state in the dfa * aa_dfa_next - step one character to the next state in the dfa
* @dfa: the dfa to tranverse (NOT NULL) * @dfa: the dfa to traverse (NOT NULL)
* @state: the state to start in * @state: the state to start in
* @c: the input character to transition on * @c: the input character to transition on
* *

View File

@ -121,7 +121,7 @@ static void audit_cb(struct audit_buffer *ab, void *va)
* @src_name: src_name of object being mediated (MAYBE_NULL) * @src_name: src_name of object being mediated (MAYBE_NULL)
* @type: type of filesystem (MAYBE_NULL) * @type: type of filesystem (MAYBE_NULL)
* @trans: name of trans (MAYBE NULL) * @trans: name of trans (MAYBE NULL)
* @flags: filesystem idependent mount flags * @flags: filesystem independent mount flags
* @data: filesystem mount flags * @data: filesystem mount flags
* @request: permissions requested * @request: permissions requested
* @perms: the permissions computed for the request (NOT NULL) * @perms: the permissions computed for the request (NOT NULL)

View File

@ -268,7 +268,7 @@ struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
if (!aa_policy_init(&profile->base, NULL, hname, gfp)) if (!aa_policy_init(&profile->base, NULL, hname, gfp))
goto fail; goto fail;
if (!aa_label_init(&profile->label, 1)) if (!aa_label_init(&profile->label, 1, gfp))
goto fail; goto fail;
/* update being set needed by fs interface */ /* update being set needed by fs interface */
@ -1008,6 +1008,9 @@ ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
audit_policy(label, op, ns_name, ent->new->base.hname, audit_policy(label, op, ns_name, ent->new->base.hname,
"same as current profile, skipping", "same as current profile, skipping",
error); error);
/* break refcount cycle with proxy. */
aa_put_proxy(ent->new->label.proxy);
ent->new->label.proxy = NULL;
goto skip; goto skip;
} }
@ -1085,7 +1088,7 @@ fail:
* Remove a profile or sub namespace from the current namespace, so that * Remove a profile or sub namespace from the current namespace, so that
* they can not be found anymore and mark them as replaced by unconfined * they can not be found anymore and mark them as replaced by unconfined
* *
* NOTE: removing confinement does not restore rlimits to preconfinemnet values * NOTE: removing confinement does not restore rlimits to preconfinement values
* *
* Returns: size of data consume else error code if fails * Returns: size of data consume else error code if fails
*/ */

View File

@ -124,7 +124,7 @@ int aa_task_setrlimit(struct aa_label *label, struct task_struct *task,
*/ */
if (label != peer && if (label != peer &&
!aa_capable(label, CAP_SYS_RESOURCE, SECURITY_CAP_NOAUDIT)) aa_capable(label, CAP_SYS_RESOURCE, SECURITY_CAP_NOAUDIT) != 0)
error = fn_for_each(label, profile, error = fn_for_each(label, profile,
audit_resource(profile, resource, audit_resource(profile, resource,
new_rlim->rlim_max, peer, new_rlim->rlim_max, peer,

View File

@ -3,7 +3,7 @@
* *
* This file contains AppArmor security identifier (secid) manipulation fns * This file contains AppArmor security identifier (secid) manipulation fns
* *
* Copyright 2009-2010 Canonical Ltd. * Copyright 2009-2017 Canonical Ltd.
* *
* This program is free software; you can redistribute it and/or * This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as * modify it under the terms of the GNU General Public License as
@ -11,38 +11,142 @@
* License. * License.
* *
* *
* AppArmor allocates a unique secid for every profile loaded. If a profile * AppArmor allocates a unique secid for every label used. If a label
* is replaced it receives the secid of the profile it is replacing. * is replaced it receives the secid of the label it is replacing.
*
* The secid value of 0 is invalid.
*/ */
#include <linux/spinlock.h>
#include <linux/errno.h> #include <linux/errno.h>
#include <linux/err.h> #include <linux/err.h>
#include <linux/gfp.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include "include/cred.h"
#include "include/lib.h"
#include "include/secid.h" #include "include/secid.h"
#include "include/label.h"
#include "include/policy_ns.h"
/* global counter from which secids are allocated */ /*
static u32 global_secid; * secids - do not pin labels with a refcount. They rely on the label
* properly updating/freeing them
*/
#define AA_FIRST_SECID 1
static DEFINE_IDR(aa_secids);
static DEFINE_SPINLOCK(secid_lock); static DEFINE_SPINLOCK(secid_lock);
/* TODO FIXME: add secid to profile mapping, and secid recycling */ /*
* TODO: allow policy to reserve a secid range?
* TODO: add secid pinning
* TODO: use secid_update in label replace
*/
/**
* aa_secid_update - update a secid mapping to a new label
* @secid: secid to update
* @label: label the secid will now map to
*/
void aa_secid_update(u32 secid, struct aa_label *label)
{
unsigned long flags;
spin_lock_irqsave(&secid_lock, flags);
idr_replace(&aa_secids, label, secid);
spin_unlock_irqrestore(&secid_lock, flags);
}
/**
*
* see label for inverse aa_label_to_secid
*/
struct aa_label *aa_secid_to_label(u32 secid)
{
struct aa_label *label;
rcu_read_lock();
label = idr_find(&aa_secids, secid);
rcu_read_unlock();
return label;
}
int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
/* TODO: cache secctx and ref count so we don't have to recreate */
struct aa_label *label = aa_secid_to_label(secid);
int len;
AA_BUG(!secdata);
AA_BUG(!seclen);
if (!label)
return -EINVAL;
if (secdata)
len = aa_label_asxprint(secdata, root_ns, label,
FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
FLAG_HIDDEN_UNCONFINED | FLAG_ABS_ROOT,
GFP_ATOMIC);
else
len = aa_label_snxprint(NULL, 0, root_ns, label,
FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
FLAG_HIDDEN_UNCONFINED | FLAG_ABS_ROOT);
if (len < 0)
return -ENOMEM;
*seclen = len;
return 0;
}
int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
{
struct aa_label *label;
label = aa_label_strn_parse(&root_ns->unconfined->label, secdata,
seclen, GFP_KERNEL, false, false);
if (IS_ERR(label))
return PTR_ERR(label);
*secid = label->secid;
return 0;
}
void apparmor_release_secctx(char *secdata, u32 seclen)
{
kfree(secdata);
}
/** /**
* aa_alloc_secid - allocate a new secid for a profile * aa_alloc_secid - allocate a new secid for a profile
* @label: the label to allocate a secid for
* @gfp: memory allocation flags
*
* Returns: 0 with @label->secid initialized
* <0 returns error with @label->secid set to AA_SECID_INVALID
*/ */
u32 aa_alloc_secid(void) int aa_alloc_secid(struct aa_label *label, gfp_t gfp)
{ {
u32 secid; unsigned long flags;
int ret;
/* idr_preload(gfp);
* TODO FIXME: secid recycling - part of profile mapping table spin_lock_irqsave(&secid_lock, flags);
*/ ret = idr_alloc(&aa_secids, label, AA_FIRST_SECID, 0, GFP_ATOMIC);
spin_lock(&secid_lock); spin_unlock_irqrestore(&secid_lock, flags);
secid = (++global_secid); idr_preload_end();
spin_unlock(&secid_lock);
return secid; if (ret < 0) {
label->secid = AA_SECID_INVALID;
return ret;
}
AA_BUG(ret == AA_SECID_INVALID);
label->secid = ret;
return 0;
} }
/** /**
@ -51,5 +155,14 @@ u32 aa_alloc_secid(void)
*/ */
void aa_free_secid(u32 secid) void aa_free_secid(u32 secid)
{ {
; /* NOP ATM */ unsigned long flags;
spin_lock_irqsave(&secid_lock, flags);
idr_remove(&aa_secids, secid);
spin_unlock_irqrestore(&secid_lock, flags);
}
void aa_secids_init(void)
{
idr_init_base(&aa_secids, AA_FIRST_SECID);
} }