Re: [PATCH v38 02/39] LSM: Add an LSM identifier for external use

[Georgia Garcia]

On Tue, 2022-09-27 at 12:53 -0700, Casey Schaufler wrote:
> Add an integer member "id" to the struct lsm_id. This value is
> a unique identifier associated with each security module. The
> values are defined in a new UAPI header file. Each existing LSM
> has been updated to include it's LSMID in the lsm_id.
> 
> Signed-off-by: Casey Schaufler <casey@xxxxxxxxxxxxxxxx>

Reviewed-by: Georgia Garcia <georgia.garcia@xxxxxxxxxxxxx>

> ---
>  include/linux/lsm_hooks.h    |  1 +
>  include/uapi/linux/lsm.h     | 32 ++++++++++++++++++++++++++++++++
>  security/apparmor/lsm.c      |  2 ++
>  security/bpf/hooks.c         |  2 ++
>  security/commoncap.c         |  2 ++
>  security/landlock/setup.c    |  2 ++
>  security/loadpin/loadpin.c   |  2 ++
>  security/lockdown/lockdown.c |  4 +++-
>  security/safesetid/lsm.c     |  2 ++
>  security/selinux/hooks.c     |  2 ++
>  security/smack/smack_lsm.c   |  2 ++
>  security/tomoyo/tomoyo.c     |  2 ++
>  security/yama/yama_lsm.c     |  2 ++
>  13 files changed, 56 insertions(+), 1 deletion(-)
>  create mode 100644 include/uapi/linux/lsm.h
> 
> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
> index 23054881eb08..407f57aaa6ef 100644
> --- a/include/linux/lsm_hooks.h
> +++ b/include/linux/lsm_hooks.h
> @@ -1603,6 +1603,7 @@ struct security_hook_heads {
>   */
>  struct lsm_id {
>  	const char	*lsm;		/* Name of the LSM */
> +	int		id;		/* LSM ID */
>  };
>  
>  /*
> diff --git a/include/uapi/linux/lsm.h b/include/uapi/linux/lsm.h
> new file mode 100644
> index 000000000000..5647c3e220c0
> --- /dev/null
> +++ b/include/uapi/linux/lsm.h
> @@ -0,0 +1,32 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Linus Security Modules (LSM) - User space API
> + *
> + * Copyright (C) 2022 Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
> + * Copyright (C) Intel Corporation
> + */
> +
> +#ifndef _UAPI_LINUX_LSM_H
> +#define _UAPI_LINUX_LSM_H
> +
> +/*
> + * ID values to identify security modules.
> + * A system may use more than one security module.
> + *
> + * LSM_ID_XXX values 32 and below are reserved for future use
> + */
> +#define LSM_ID_INVALID		-1
> +#define LSM_ID_SELINUX		33
> +#define LSM_ID_SMACK		34
> +#define LSM_ID_TOMOYO		35
> +#define LSM_ID_IMA		36
> +#define LSM_ID_APPARMOR		37
> +#define LSM_ID_YAMA		38
> +#define LSM_ID_LOADPIN		39
> +#define LSM_ID_SAFESETID	40
> +#define LSM_ID_LOCKDOWN		41
> +#define LSM_ID_BPF		42
> +#define LSM_ID_LANDLOCK		43
> +#define LSM_ID_CAPABILITY	44
> +
> +#endif /* _UAPI_LINUX_LSM_H */
> diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
> index b71f7d4159d7..fb6c7edd5393 100644
> --- a/security/apparmor/lsm.c
> +++ b/security/apparmor/lsm.c
> @@ -24,6 +24,7 @@
>  #include <linux/zlib.h>
>  #include <net/sock.h>
>  #include <uapi/linux/mount.h>
> +#include <uapi/linux/lsm.h>
>  
>  #include "include/apparmor.h"
>  #include "include/apparmorfs.h"
> @@ -1204,6 +1205,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
>  
>  static struct lsm_id apparmor_lsmid __lsm_ro_after_init = {
>  	.lsm      = "apparmor",
> +	.id       = LSM_ID_APPARMOR,
>  };
>  
>  static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
> diff --git a/security/bpf/hooks.c b/security/bpf/hooks.c
> index e50de3abfde2..c462fc41dd57 100644
> --- a/security/bpf/hooks.c
> +++ b/security/bpf/hooks.c
> @@ -5,6 +5,7 @@
>   */
>  #include <linux/lsm_hooks.h>
>  #include <linux/bpf_lsm.h>
> +#include <uapi/linux/lsm.h>
>  
>  static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = {
>  	#define LSM_HOOK(RET, DEFAULT, NAME, ...) \
> @@ -21,6 +22,7 @@ static struct security_hook_list bpf_lsm_hooks[] __lsm_ro_after_init = {
>   */
>  struct lsm_id bpf_lsmid __lsm_ro_after_init = {
>  	.lsm      = "bpf",
> +	.id       = LSM_ID_BPF,
>  };
>  
>  static int __init bpf_lsm_init(void)
> diff --git a/security/commoncap.c b/security/commoncap.c
> index dab1b5f5e6aa..4e9b140159d8 100644
> --- a/security/commoncap.c
> +++ b/security/commoncap.c
> @@ -25,6 +25,7 @@
>  #include <linux/binfmts.h>
>  #include <linux/personality.h>
>  #include <linux/mnt_idmapping.h>
> +#include <uapi/linux/lsm.h>
>  
>  /*
>   * If a non-root user executes a setuid-root binary in
> @@ -1448,6 +1449,7 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
>  
>  static struct lsm_id capability_lsmid __lsm_ro_after_init = {
>  	.lsm      = "capability",
> +	.id       = LSM_ID_CAPABILITY,
>  };
>  
>  static struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
> diff --git a/security/landlock/setup.c b/security/landlock/setup.c
> index fc7b69c5839e..1242c61c9de4 100644
> --- a/security/landlock/setup.c
> +++ b/security/landlock/setup.c
> @@ -8,6 +8,7 @@
>  
>  #include <linux/init.h>
>  #include <linux/lsm_hooks.h>
> +#include <uapi/linux/lsm.h>
>  
>  #include "common.h"
>  #include "cred.h"
> @@ -25,6 +26,7 @@ struct lsm_blob_sizes landlock_blob_sizes __lsm_ro_after_init = {
>  
>  struct lsm_id landlock_lsmid __lsm_ro_after_init = {
>  	.lsm      = LANDLOCK_NAME,
> +	.id       = LSM_ID_LANDLOCK,
>  };
>  
>  static int __init landlock_init(void)
> diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
> index 7e5c897ccbb2..276c8a7cd6fe 100644
> --- a/security/loadpin/loadpin.c
> +++ b/security/loadpin/loadpin.c
> @@ -20,6 +20,7 @@
>  #include <linux/string_helpers.h>
>  #include <linux/dm-verity-loadpin.h>
>  #include <uapi/linux/loadpin.h>
> +#include <uapi/linux/lsm.h>
>  
>  static void report_load(const char *origin, struct file *file, char *operation)
>  {
> @@ -197,6 +198,7 @@ static int loadpin_load_data(enum kernel_load_data_id id, bool contents)
>  
>  static struct lsm_id loadpin_lsmid __lsm_ro_after_init = {
>  	.lsm      = "loadpin",
> +	.id       = LSM_ID_LOADPIN,
>  };
>  
>  static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
> diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
> index 2af4bff8d101..3d3347f3dbd1 100644
> --- a/security/lockdown/lockdown.c
> +++ b/security/lockdown/lockdown.c
> @@ -13,6 +13,7 @@
>  #include <linux/security.h>
>  #include <linux/export.h>
>  #include <linux/lsm_hooks.h>
> +#include <uapi/linux/lsm.h>
>  
>  static enum lockdown_reason kernel_locked_down;
>  
> @@ -76,7 +77,8 @@ static struct security_hook_list lockdown_hooks[] __lsm_ro_after_init = {
>  };
>  
>  static struct lsm_id lockdown_lsmid __lsm_ro_after_init = {
> -	.lsm     = "lockdown",
> +	.lsm      = "lockdown",
> +	.id       = LSM_ID_LOCKDOWN,
>  };
>  
>  static int __init lockdown_lsm_init(void)
> diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c
> index 3a94103f3c5b..88002731e603 100644
> --- a/security/safesetid/lsm.c
> +++ b/security/safesetid/lsm.c
> @@ -19,6 +19,7 @@
>  #include <linux/ptrace.h>
>  #include <linux/sched/task_stack.h>
>  #include <linux/security.h>
> +#include <uapi/linux/lsm.h>
>  #include "lsm.h"
>  
>  /* Flag indicating whether initialization completed */
> @@ -263,6 +264,7 @@ static int safesetid_task_fix_setgroups(struct cred *new, const struct cred *old
>  
>  static struct lsm_id safesetid_lsmid __lsm_ro_after_init = {
>  	.lsm      = "safesetid",
> +	.id       = LSM_ID_SAFESETID,
>  };
>  
>  static struct security_hook_list safesetid_security_hooks[] = {
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index 5e4938f3ce11..9803bbbc6747 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -92,6 +92,7 @@
>  #include <linux/fsnotify.h>
>  #include <linux/fanotify.h>
>  #include <linux/io_uring.h>
> +#include <uapi/linux/lsm.h>
>  
>  #include "avc.h"
>  #include "objsec.h"
> @@ -7014,6 +7015,7 @@ static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
>  
>  static struct lsm_id selinux_lsmid __lsm_ro_after_init = {
>  	.lsm      = "selinux",
> +	.id       = LSM_ID_SELINUX,
>  };
>  
>  /*
> diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
> index 5d8bc13feb09..2a88b4e7669e 100644
> --- a/security/smack/smack_lsm.c
> +++ b/security/smack/smack_lsm.c
> @@ -43,6 +43,7 @@
>  #include <linux/fs_parser.h>
>  #include <linux/watch_queue.h>
>  #include <linux/io_uring.h>
> +#include <uapi/linux/lsm.h>
>  #include "smack.h"
>  
>  #define TRANS_TRUE	"TRUE"
> @@ -4776,6 +4777,7 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
>  
>  static struct lsm_id smack_lsmid __lsm_ro_after_init = {
>  	.lsm      = "smack",
> +	.id       = LSM_ID_SMACK,
>  };
>  
>  static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
> diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
> index 38342c1fa4bc..71eab206ba6e 100644
> --- a/security/tomoyo/tomoyo.c
> +++ b/security/tomoyo/tomoyo.c
> @@ -6,6 +6,7 @@
>   */
>  
>  #include <linux/lsm_hooks.h>
> +#include <uapi/linux/lsm.h>
>  #include "common.h"
>  
>  /**
> @@ -532,6 +533,7 @@ static void tomoyo_task_free(struct task_struct *task)
>  
>  static struct lsm_id tomoyo_lsmid __lsm_ro_after_init = {
>  	.lsm      = "tomoyo",
> +	.id       = LSM_ID_TOMOYO,
>  };
>  
>  /*
> diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
> index ed6d45e62e0d..b178d74bb00b 100644
> --- a/security/yama/yama_lsm.c
> +++ b/security/yama/yama_lsm.c
> @@ -18,6 +18,7 @@
>  #include <linux/task_work.h>
>  #include <linux/sched.h>
>  #include <linux/spinlock.h>
> +#include <uapi/linux/lsm.h>
>  
>  #define YAMA_SCOPE_DISABLED	0
>  #define YAMA_SCOPE_RELATIONAL	1
> @@ -423,6 +424,7 @@ static int yama_ptrace_traceme(struct task_struct *parent)
>  
>  static struct lsm_id yama_lsmid __lsm_ro_after_init = {
>  	.lsm      = "yama",
> +	.id       = LSM_ID_YAMA,
>  };
>  
>  static struct security_hook_list yama_hooks[] __lsm_ro_after_init = {