@@ -37,6 +37,10 @@ static const struct proc_ns_operations *ns_entries[] = {
&timens_operations,
&timens_for_children_operations,
#endif
+#ifdef CONFIG_IMA_NS
+ &imans_operations,
+ &imans_for_children_operations,
+#endif
};
static const char *proc_ns_get_link(struct dentry *dentry,
@@ -12,6 +12,9 @@
#include <linux/kexec.h>
struct linux_binprm;
+struct nsproxy;
+struct task_struct;
+
#ifdef CONFIG_IMA
extern int ima_bprm_check(struct linux_binprm *bprm);
extern int ima_file_check(struct file *file, int mask);
@@ -167,4 +170,58 @@ static inline bool ima_appraise_signature(enum kernel_read_file_id func)
return false;
}
#endif /* CONFIG_IMA_APPRAISE && CONFIG_INTEGRITY_TRUSTED_KEYRING */
+
+struct ima_namespace {
+ struct kref kref;
+ struct ns_common ns;
+ struct ucounts *ucounts;
+ struct user_namespace *user_ns;
+} __randomize_layout;
+
+extern struct ima_namespace init_ima_ns;
+
+#ifdef CONFIG_IMA_NS
+struct ima_namespace *copy_ima_ns(unsigned long flags,
+ struct user_namespace *user_ns,
+ struct ima_namespace *old_ns);
+
+void free_ima_ns(struct kref *kref);
+
+int imans_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
+
+static inline struct ima_namespace *get_ima_ns(struct ima_namespace *ns)
+{
+ if (ns)
+ kref_get(&ns->kref);
+ return ns;
+}
+static inline void put_ima_ns(struct ima_namespace *ns)
+{
+ if (ns)
+ kref_put(&ns->kref, free_ima_ns);
+}
+
+#else
+static inline struct ima_namespace *copy_ima_ns(unsigned long flags,
+ struct user_namespace *user_ns,
+ struct ima_namespace *old_ns)
+{
+ return old_ns;
+}
+
+static inline int imans_on_fork(struct nsproxy *nsproxy,
+ struct task_struct *tsk)
+{
+ return 0;
+}
+
+static inline struct ima_namespace *get_ima_ns(struct ima_namespace *ns)
+{
+ return ns;
+}
+
+static inline void put_ima_ns(struct ima_namespace *ns)
+{
+}
+#endif /* CONFIG_IMA_NS */
#endif /* _LINUX_IMA_H */
@@ -10,6 +10,7 @@ struct uts_namespace;
struct ipc_namespace;
struct pid_namespace;
struct cgroup_namespace;
+struct ima_namespace;
struct fs_struct;
/*
@@ -38,6 +39,8 @@ struct nsproxy {
struct time_namespace *time_ns;
struct time_namespace *time_ns_for_children;
struct cgroup_namespace *cgroup_ns;
+ struct ima_namespace *ima_ns;
+ struct ima_namespace *ima_ns_for_children;
};
extern struct nsproxy init_nsproxy;
@@ -16,7 +16,7 @@ struct inode;
struct proc_ns_operations {
const char *name;
const char *real_ns_name;
- int type;
+ unsigned long type;
struct ns_common *(*get)(struct task_struct *task);
void (*put)(struct ns_common *ns);
int (*install)(struct nsset *nsset, struct ns_common *ns);
@@ -34,6 +34,8 @@ extern const struct proc_ns_operations mntns_operations;
extern const struct proc_ns_operations cgroupns_operations;
extern const struct proc_ns_operations timens_operations;
extern const struct proc_ns_operations timens_for_children_operations;
+extern const struct proc_ns_operations imans_operations;
+extern const struct proc_ns_operations imans_for_children_operations;
/*
* We always define these enumerators
@@ -46,6 +48,7 @@ enum {
PROC_PID_INIT_INO = 0xEFFFFFFCU,
PROC_CGROUP_INIT_INO = 0xEFFFFFFBU,
PROC_TIME_INIT_INO = 0xEFFFFFFAU,
+ PROC_IMA_INIT_INO = 0xEFFFFFF9U,
};
#ifdef CONFIG_PROC_FS
@@ -46,6 +46,7 @@ enum ucount_type {
UCOUNT_MNT_NAMESPACES,
UCOUNT_CGROUP_NAMESPACES,
UCOUNT_TIME_NAMESPACES,
+ UCOUNT_IMA_NAMESPACES,
#ifdef CONFIG_INOTIFY_USER
UCOUNT_INOTIFY_INSTANCES,
UCOUNT_INOTIFY_WATCHES,
@@ -36,6 +36,7 @@
/* Flags for the clone3() syscall. */
#define CLONE_CLEAR_SIGHAND 0x100000000ULL /* Clear any signal handler and reset to SIG_DFL. */
#define CLONE_INTO_CGROUP 0x200000000ULL /* Clone into a specific cgroup given the right permissions. */
+#define CLONE_NEWIMA 0x400000000ULL /* New IMA namespace. */
/*
* cloning flags intersect with CSIGNAL so can be used with unshare and clone3
@@ -1184,6 +1184,18 @@ config NET_NS
Allow user space to create what appear to be multiple instances
of the network stack.
+config IMA_NS
+ bool "IMA namespace"
+ depends on IMA
+ default n
+ help
+ This allows container engines to use ima namespaces to provide
+ different IMA policy rules for different containers. Also, it allows
+ to create what appear to be multiple instances of the IMA measurement
+ list and other IMA related resources.
+
+ If unsure, say N.
+
endif # NAMESPACES
config CHECKPOINT_RESTORE
@@ -1876,11 +1876,24 @@ static __latent_entropy struct task_struct *copy_process(
}
/*
- * If the new process will be in a different time namespace
- * do not allow it to share VM or a thread group with the forking task.
+ * If the new process will be in a different time namespace or a
+ * different ima namespace, do not allow it to share VM or a thread
+ * group with the forking task.
*/
if (clone_flags & (CLONE_THREAD | CLONE_VM)) {
- if (nsp->time_ns != nsp->time_ns_for_children)
+ if ((nsp->time_ns != nsp->time_ns_for_children) ||
+ ((clone_flags & CLONE_NEWIMA) ||
+ (nsp->ima_ns != nsp->ima_ns_for_children)))
+ return ERR_PTR(-EINVAL);
+ }
+
+ /*
+ * If the new process will be in a different ima namespace
+ * do not allow it to share the same file descriptor table.
+ */
+ if (clone_flags & CLONE_FILES) {
+ if ((clone_flags & CLONE_NEWIMA) ||
+ (nsp->ima_ns != nsp->ima_ns_for_children))
return ERR_PTR(-EINVAL);
}
@@ -2649,7 +2662,8 @@ static bool clone3_args_valid(struct kernel_clone_args *kargs)
{
/* Verify that no unknown flags are passed along. */
if (kargs->flags &
- ~(CLONE_LEGACY_FLAGS | CLONE_CLEAR_SIGHAND | CLONE_INTO_CGROUP))
+ ~(CLONE_LEGACY_FLAGS |
+ CLONE_CLEAR_SIGHAND | CLONE_INTO_CGROUP | CLONE_NEWIMA))
return false;
/*
@@ -2796,7 +2810,7 @@ static int check_unshare_flags(unsigned long unshare_flags)
CLONE_VM|CLONE_FILES|CLONE_SYSVSEM|
CLONE_NEWUTS|CLONE_NEWIPC|CLONE_NEWNET|
CLONE_NEWUSER|CLONE_NEWPID|CLONE_NEWCGROUP|
- CLONE_NEWTIME))
+ CLONE_NEWTIME|CLONE_NEWIMA))
return -EINVAL;
/*
* Not implemented, but pretend it works if there is nothing
@@ -19,6 +19,7 @@
#include <net/net_namespace.h>
#include <linux/ipc_namespace.h>
#include <linux/time_namespace.h>
+#include <linux/ima.h>
#include <linux/fs_struct.h>
#include <linux/proc_fs.h>
#include <linux/proc_ns.h>
@@ -47,6 +48,10 @@ struct nsproxy init_nsproxy = {
.time_ns = &init_time_ns,
.time_ns_for_children = &init_time_ns,
#endif
+#ifdef CONFIG_IMA_NS
+ .ima_ns = &init_ima_ns,
+ .ima_ns_for_children = &init_ima_ns,
+#endif
};
static inline struct nsproxy *create_nsproxy(void)
@@ -121,8 +126,19 @@ static struct nsproxy *create_new_namespaces(unsigned long flags,
}
new_nsp->time_ns = get_time_ns(tsk->nsproxy->time_ns);
+ new_nsp->ima_ns_for_children = copy_ima_ns(flags, user_ns,
+ tsk->nsproxy->ima_ns_for_children);
+ if (IS_ERR(new_nsp->ima_ns_for_children)) {
+ err = PTR_ERR(new_nsp->ima_ns_for_children);
+ goto out_ima;
+ }
+ new_nsp->ima_ns = get_ima_ns(tsk->nsproxy->ima_ns);
+
return new_nsp;
+out_ima:
+ put_time_ns(new_nsp->time_ns);
+ put_time_ns(new_nsp->time_ns_for_children);
out_time:
put_net(new_nsp->net_ns);
out_net:
@@ -157,8 +173,10 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
if (likely(!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
CLONE_NEWPID | CLONE_NEWNET |
- CLONE_NEWCGROUP | CLONE_NEWTIME)))) {
- if (likely(old_ns->time_ns_for_children == old_ns->time_ns)) {
+ CLONE_NEWCGROUP | CLONE_NEWTIME |
+ CLONE_NEWIMA)))) {
+ if (likely((old_ns->time_ns_for_children == old_ns->time_ns) &&
+ (old_ns->ima_ns_for_children == old_ns->ima_ns))) {
get_nsproxy(old_ns);
return 0;
}
@@ -186,6 +204,12 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
return ret;
}
+ ret = imans_on_fork(new_ns, tsk);
+ if (ret) {
+ free_nsproxy(new_ns);
+ return ret;
+ }
+
tsk->nsproxy = new_ns;
return 0;
}
@@ -204,6 +228,10 @@ void free_nsproxy(struct nsproxy *ns)
put_time_ns(ns->time_ns);
if (ns->time_ns_for_children)
put_time_ns(ns->time_ns_for_children);
+ if (ns->ima_ns)
+ put_ima_ns(ns->ima_ns);
+ if (ns->ima_ns_for_children)
+ put_ima_ns(ns->ima_ns_for_children);
put_cgroup_ns(ns->cgroup_ns);
put_net(ns->net_ns);
kmem_cache_free(nsproxy_cachep, ns);
@@ -221,7 +249,7 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags,
if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC |
CLONE_NEWNET | CLONE_NEWPID | CLONE_NEWCGROUP |
- CLONE_NEWTIME)))
+ CLONE_NEWTIME | CLONE_NEWIMA)))
return 0;
user_ns = new_cred ? new_cred->user_ns : current_user_ns();
@@ -70,6 +70,7 @@ static struct ctl_table user_table[] = {
UCOUNT_ENTRY("max_mnt_namespaces"),
UCOUNT_ENTRY("max_cgroup_namespaces"),
UCOUNT_ENTRY("max_time_namespaces"),
+ UCOUNT_ENTRY("max_ima_namespaces"),
#ifdef CONFIG_INOTIFY_USER
UCOUNT_ENTRY("max_inotify_instances"),
UCOUNT_ENTRY("max_inotify_watches"),
@@ -14,3 +14,4 @@ ima-$(CONFIG_HAVE_IMA_KEXEC) += ima_kexec.o
ima-$(CONFIG_IMA_BLACKLIST_KEYRING) += ima_mok.o
ima-$(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) += ima_asymmetric_keys.o
ima-$(CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS) += ima_queue_keys.o
+ima-$(CONFIG_IMA_NS) += ima_ns.o
@@ -20,6 +20,7 @@
#include <linux/hash.h>
#include <linux/tpm.h>
#include <linux/audit.h>
+#include <linux/ima.h>
#include <crypto/hash_info.h>
#include "../integrity.h"
@@ -371,6 +372,18 @@ static inline int ima_read_xattr(struct dentry *dentry,
#endif /* CONFIG_IMA_APPRAISE */
+#ifdef CONFIG_IMA_NS
+static inline struct ima_namespace *get_current_ns(void)
+{
+ return current->nsproxy->ima_ns;
+}
+#else
+static inline struct ima_namespace *get_current_ns(void)
+{
+ return &init_ima_ns;
+}
+#endif /* CONFIG_IMA_NS */
+
#ifdef CONFIG_IMA_APPRAISE_MODSIG
int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
struct modsig **modsig);
@@ -15,6 +15,9 @@
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/err.h>
+#include <linux/kref.h>
+#include <linux/proc_ns.h>
+#include <linux/user_namespace.h>
#include "ima.h"
@@ -22,6 +25,16 @@
const char boot_aggregate_name[] = "boot_aggregate";
struct tpm_chip *ima_tpm_chip;
+struct ima_namespace init_ima_ns = {
+ .kref = KREF_INIT(2),
+ .user_ns = &init_user_ns,
+ .ns.inum = PROC_IMA_INIT_INO,
+#ifdef CONFIG_IMA_NS
+ .ns.ops = &imans_operations,
+#endif
+};
+EXPORT_SYMBOL(init_ima_ns);
+
/* Add the boot aggregate to the IMA measurement list and extend
* the PCR register.
*
new file mode 100644
@@ -0,0 +1,232 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019-2020 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Krzysztof Struczynski <krzysztof.struczynski@huawei.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ * File: ima_ns.c
+ * Functions to manage the IMA namespace.
+ */
+
+#include <linux/export.h>
+#include <linux/ima.h>
+#include <linux/kref.h>
+#include <linux/proc_ns.h>
+#include <linux/slab.h>
+#include <linux/user_namespace.h>
+#include <linux/nsproxy.h>
+#include <linux/sched.h>
+
+#include "ima.h"
+
+static struct ucounts *inc_ima_namespaces(struct user_namespace *ns)
+{
+ return inc_ucount(ns, current_euid(), UCOUNT_IMA_NAMESPACES);
+}
+
+static void dec_ima_namespaces(struct ucounts *ucounts)
+{
+ return dec_ucount(ucounts, UCOUNT_IMA_NAMESPACES);
+}
+
+static struct ima_namespace *ima_ns_alloc(void)
+{
+ struct ima_namespace *ima_ns;
+
+ ima_ns = kzalloc(sizeof(*ima_ns), GFP_KERNEL);
+ if (!ima_ns)
+ return NULL;
+
+ return ima_ns;
+}
+
+/**
+ * Clone a new ns copying an original ima namespace, setting refcount to 1
+ *
+ * @user_ns: User namespace that current task runs in
+ * @old_ns: Old ima namespace to clone
+ * Return: ERR_PTR(-ENOMEM) on error (failure to kmalloc), new ns otherwise
+ */
+static struct ima_namespace *clone_ima_ns(struct user_namespace *user_ns,
+ struct ima_namespace *old_ns)
+{
+ struct ima_namespace *ns;
+ struct ucounts *ucounts;
+ int err;
+
+ err = -ENOSPC;
+ ucounts = inc_ima_namespaces(user_ns);
+ if (!ucounts)
+ goto fail;
+
+ err = -ENOMEM;
+ ns = ima_ns_alloc();
+ if (!ns)
+ goto fail_dec;
+
+ kref_init(&ns->kref);
+
+ err = ns_alloc_inum(&ns->ns);
+ if (err)
+ goto fail_free;
+
+ ns->ns.ops = &imans_operations;
+ ns->user_ns = get_user_ns(user_ns);
+ ns->ucounts = ucounts;
+
+ return ns;
+
+fail_free:
+ kfree(ns);
+fail_dec:
+ dec_ima_namespaces(ucounts);
+fail:
+ return ERR_PTR(err);
+}
+
+/**
+ * Copy task's ima namespace, or clone it if flags specifies CLONE_NEWNS.
+ *
+ * @flags: Cloning flags
+ * @user_ns: User namespace that current task runs in
+ * @old_ns: Old ima namespace to clone
+ *
+ * Return: IMA namespace or ERR_PTR.
+ */
+
+struct ima_namespace *copy_ima_ns(unsigned long flags,
+ struct user_namespace *user_ns,
+ struct ima_namespace *old_ns)
+{
+ if (!(flags & CLONE_NEWIMA))
+ return get_ima_ns(old_ns);
+
+ return clone_ima_ns(user_ns, old_ns);
+}
+
+static void destroy_ima_ns(struct ima_namespace *ns)
+{
+ dec_ima_namespaces(ns->ucounts);
+ put_user_ns(ns->user_ns);
+ ns_free_inum(&ns->ns);
+ kfree(ns);
+}
+
+void free_ima_ns(struct kref *kref)
+{
+ struct ima_namespace *ns;
+
+ ns = container_of(kref, struct ima_namespace, kref);
+
+ destroy_ima_ns(ns);
+}
+
+static inline struct ima_namespace *to_ima_ns(struct ns_common *ns)
+{
+ return container_of(ns, struct ima_namespace, ns);
+}
+
+static struct ns_common *imans_get(struct task_struct *task)
+{
+ struct ima_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ task_lock(task);
+ nsproxy = task->nsproxy;
+ if (nsproxy) {
+ ns = nsproxy->ima_ns;
+ get_ima_ns(ns);
+ }
+ task_unlock(task);
+
+ return ns ? &ns->ns : NULL;
+}
+
+static struct ns_common *imans_for_children_get(struct task_struct *task)
+{
+ struct ima_namespace *ns = NULL;
+ struct nsproxy *nsproxy;
+
+ task_lock(task);
+ nsproxy = task->nsproxy;
+ if (nsproxy) {
+ ns = nsproxy->ima_ns_for_children;
+ get_ima_ns(ns);
+ }
+ task_unlock(task);
+
+ return ns ? &ns->ns : NULL;
+}
+
+static void imans_put(struct ns_common *ns)
+{
+ put_ima_ns(to_ima_ns(ns));
+}
+
+static int imans_install(struct nsset *nsset, struct ns_common *new)
+{
+ struct nsproxy *nsproxy = nsset->nsproxy;
+ struct ima_namespace *ns = to_ima_ns(new);
+
+ if (!current_is_single_threaded())
+ return -EUSERS;
+
+ if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) ||
+ !ns_capable(nsset->cred->user_ns, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ get_ima_ns(ns);
+ put_ima_ns(nsproxy->ima_ns);
+ nsproxy->ima_ns = ns;
+
+ get_ima_ns(ns);
+ put_ima_ns(nsproxy->ima_ns_for_children);
+ nsproxy->ima_ns_for_children = ns;
+
+ return 0;
+}
+
+int imans_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk)
+{
+ struct ns_common *nsc = &nsproxy->ima_ns_for_children->ns;
+ struct ima_namespace *ns = to_ima_ns(nsc);
+
+ /* create_new_namespaces() already incremented the ref counter */
+ if (nsproxy->ima_ns == nsproxy->ima_ns_for_children)
+ return 0;
+
+ get_ima_ns(ns);
+ put_ima_ns(nsproxy->ima_ns);
+ nsproxy->ima_ns = ns;
+
+ return 0;
+}
+
+static struct user_namespace *imans_owner(struct ns_common *ns)
+{
+ return to_ima_ns(ns)->user_ns;
+}
+
+const struct proc_ns_operations imans_operations = {
+ .name = "ima",
+ .type = CLONE_NEWIMA,
+ .get = imans_get,
+ .put = imans_put,
+ .install = imans_install,
+ .owner = imans_owner,
+};
+
+const struct proc_ns_operations imans_for_children_operations = {
+ .name = "ima_for_children",
+ .type = CLONE_NEWIMA,
+ .get = imans_for_children_get,
+ .put = imans_put,
+ .install = imans_install,
+ .owner = imans_owner,
+};
+