Subject: [PATCH v12 8/9] LSM: Multiple concurrent LSMs

Change the infrastructure for Linux Security Modules (LSM)s
from a single vector of hook handlers to a list based method
for handling multiple concurrent modules. 

Abstract access to security blobs.
Remove commoncap calls.

Signed-off-by: Casey Schaufler <ca...@schaufler-ca.com>

---
 security/tomoyo/common.h        |    6 +++--
 security/tomoyo/domain.c        |    2 +-
 security/tomoyo/securityfs_if.c |    9 +++++---
 security/tomoyo/tomoyo.c        |   47 ++++++++++++++++++++++-----------------
 4 files changed, 38 insertions(+), 26 deletions(-)

diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index d4f166b..ef0cdcc 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -28,6 +28,7 @@
 #include <linux/in.h>
 #include <linux/in6.h>
 #include <linux/un.h>
+#include <linux/lsm.h>
 #include <net/sock.h>
 #include <net/af_unix.h>
 #include <net/ip.h>
@@ -1079,6 +1080,7 @@ extern struct list_head tomoyo_domain_list;
 extern struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
 extern struct list_head tomoyo_namespace_list;
 extern struct mutex tomoyo_policy_lock;
+extern struct security_operations tomoyo_security_ops;
 extern struct srcu_struct tomoyo_ss;
 extern struct tomoyo_domain_info tomoyo_kernel_domain;
 extern struct tomoyo_policy_namespace tomoyo_kernel_namespace;
@@ -1202,7 +1204,7 @@ static inline void tomoyo_put_group(struct tomoyo_group 
*group)
  */
 static inline struct tomoyo_domain_info *tomoyo_domain(void)
 {
-       return current_cred()->security;
+       return lsm_get_cred(current_cred(), &tomoyo_security_ops);
 }
 
 /**
@@ -1215,7 +1217,7 @@ static inline struct tomoyo_domain_info 
*tomoyo_domain(void)
 static inline struct tomoyo_domain_info *tomoyo_real_domain(struct task_struct
                                                            *task)
 {
-       return task_cred_xxx(task, security);
+       return lsm_get_cred(__task_cred(task), &tomoyo_security_ops);
 }
 
 /**
diff --git a/security/tomoyo/domain.c b/security/tomoyo/domain.c
index 3865145..15042e7 100644
--- a/security/tomoyo/domain.c
+++ b/security/tomoyo/domain.c
@@ -840,7 +840,7 @@ force_jump_domain:
                domain = old_domain;
        /* Update reference count on "struct tomoyo_domain_info". */
        atomic_inc(&domain->users);
-       bprm->cred->security = domain;
+       lsm_set_cred(bprm->cred, domain, &tomoyo_security_ops);
        kfree(exename.name);
        if (!retval) {
                ee->r.domain = domain;
diff --git a/security/tomoyo/securityfs_if.c b/security/tomoyo/securityfs_if.c
index 8592f2fc..37feaf5 100644
--- a/security/tomoyo/securityfs_if.c
+++ b/security/tomoyo/securityfs_if.c
@@ -75,8 +75,10 @@ static ssize_t tomoyo_write_self(struct file *file, const 
char __user *buf,
                                        error = -ENOMEM;
                                } else {
                                        struct tomoyo_domain_info *old_domain =
-                                               cred->security;
-                                       cred->security = new_domain;
+                                               lsm_get_cred(cred,
+                                                       &tomoyo_security_ops);
+                                       lsm_set_cred(cred, new_domain,
+                                                       &tomoyo_security_ops);
                                        atomic_inc(&new_domain->users);
                                        atomic_dec(&old_domain->users);
                                        commit_creds(cred);
@@ -242,7 +244,8 @@ static int __init tomoyo_initerface_init(void)
        struct dentry *tomoyo_dir;
 
        /* Don't create securityfs entries unless registered. */
-       if (current_cred()->security != &tomoyo_kernel_domain)
+       if (lsm_get_cred(current_cred(), &tomoyo_security_ops) !=
+                       &tomoyo_kernel_domain)
                return 0;
 
        tomoyo_dir = securityfs_create_dir("tomoyo", NULL);
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index a2ee362..b2a58ae 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -17,7 +17,7 @@
  */
 static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
 {
-       new->security = NULL;
+       lsm_set_cred(new, NULL, &tomoyo_security_ops);
        return 0;
 }
 
@@ -33,8 +33,10 @@ static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t 
gfp)
 static int tomoyo_cred_prepare(struct cred *new, const struct cred *old,
                               gfp_t gfp)
 {
-       struct tomoyo_domain_info *domain = old->security;
-       new->security = domain;
+       struct tomoyo_domain_info *domain;
+
+       domain = lsm_get_cred(old, &tomoyo_security_ops);
+       lsm_set_cred(new, domain, &tomoyo_security_ops);
        if (domain)
                atomic_inc(&domain->users);
        return 0;
@@ -58,9 +60,13 @@ static void tomoyo_cred_transfer(struct cred *new, const 
struct cred *old)
  */
 static void tomoyo_cred_free(struct cred *cred)
 {
-       struct tomoyo_domain_info *domain = cred->security;
-       if (domain)
+       struct tomoyo_domain_info *domain;
+
+       domain = lsm_get_cred(cred, &tomoyo_security_ops);
+       if (domain) {
                atomic_dec(&domain->users);
+               lsm_set_cred(cred, NULL, &tomoyo_security_ops);
+       }
 }
 
 /**
@@ -72,12 +78,6 @@ static void tomoyo_cred_free(struct cred *cred)
  */
 static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
 {
-       int rc;
-
-       rc = cap_bprm_set_creds(bprm);
-       if (rc)
-               return rc;
-
        /*
         * Do only if this function is called for the first time of an execve
         * operation.
@@ -98,13 +98,13 @@ static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
         * stored inside "bprm->cred->security" will be acquired later inside
         * tomoyo_find_next_domain().
         */
-       atomic_dec(&((struct tomoyo_domain_info *)
-                    bprm->cred->security)->users);
+       atomic_dec(&((struct tomoyo_domain_info *)lsm_get_cred(bprm->cred,
+                                               &tomoyo_security_ops))->users);
        /*
         * Tell tomoyo_bprm_check_security() is called for the first time of an
         * execve operation.
         */
-       bprm->cred->security = NULL;
+       lsm_set_cred(bprm->cred, NULL, &tomoyo_security_ops);
        return 0;
 }
 
@@ -117,8 +117,9 @@ static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
  */
 static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
 {
-       struct tomoyo_domain_info *domain = bprm->cred->security;
+       struct tomoyo_domain_info *domain;
 
+       domain = lsm_get_cred(bprm->cred, &tomoyo_security_ops);
        /*
         * Execute permission is checked against pathname passed to do_execve()
         * using current domain.
@@ -503,7 +504,7 @@ static int tomoyo_socket_sendmsg(struct socket *sock, 
struct msghdr *msg,
  * tomoyo_security_ops is a "struct security_operations" which is used for
  * registering TOMOYO.
  */
-static struct security_operations tomoyo_security_ops = {
+struct security_operations tomoyo_security_ops = {
        .name                = "tomoyo",
        .cred_alloc_blank    = tomoyo_cred_alloc_blank,
        .cred_prepare        = tomoyo_cred_prepare,
@@ -545,16 +546,22 @@ struct srcu_struct tomoyo_ss;
  */
 static int __init tomoyo_init(void)
 {
+       int rc;
        struct cred *cred = (struct cred *) current_cred();
 
+       /* register ourselves with the security framework */
        if (!security_module_enable(&tomoyo_security_ops))
                return 0;
-       /* register ourselves with the security framework */
-       if (register_security(&tomoyo_security_ops) ||
-           init_srcu_struct(&tomoyo_ss))
+
+       if (init_srcu_struct(&tomoyo_ss))
                panic("Failure registering TOMOYO Linux");
        printk(KERN_INFO "TOMOYO Linux initialized\n");
-       cred->security = &tomoyo_kernel_domain;
+
+       rc = lsm_set_init_cred(cred, &tomoyo_kernel_domain,
+                               &tomoyo_security_ops);
+       if (rc)
+               panic("Failure allocating credential for TOMOYO Linux");
+
        tomoyo_mm_init();
        return 0;
 }

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to