diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/key.h | 33 | ||||
-rw-r--r-- | include/linux/lsm_audit.h | 1 | ||||
-rw-r--r-- | include/linux/lsm_hook_defs.h | 9 | ||||
-rw-r--r-- | include/linux/lsm_hooks.h | 14 | ||||
-rw-r--r-- | include/linux/pipe_fs_i.h | 27 | ||||
-rw-r--r-- | include/linux/security.h | 30 | ||||
-rw-r--r-- | include/linux/watch_queue.h | 127 | ||||
-rw-r--r-- | include/uapi/linux/keyctl.h | 2 | ||||
-rw-r--r-- | include/uapi/linux/watch_queue.h | 104 |
9 files changed, 331 insertions, 16 deletions
diff --git a/include/linux/key.h b/include/linux/key.h index 6cf8e71cf8b7..0f2e24f13c2b 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -71,6 +71,23 @@ struct net; #define KEY_PERM_UNDEF 0xffffffff +/* + * The permissions required on a key that we're looking up. + */ +enum key_need_perm { + KEY_NEED_UNSPECIFIED, /* Needed permission unspecified */ + KEY_NEED_VIEW, /* Require permission to view attributes */ + KEY_NEED_READ, /* Require permission to read content */ + KEY_NEED_WRITE, /* Require permission to update / modify */ + KEY_NEED_SEARCH, /* Require permission to search (keyring) or find (key) */ + KEY_NEED_LINK, /* Require permission to link */ + KEY_NEED_SETATTR, /* Require permission to change attributes */ + KEY_NEED_UNLINK, /* Require permission to unlink key */ + KEY_SYSADMIN_OVERRIDE, /* Special: override by CAP_SYS_ADMIN */ + KEY_AUTHTOKEN_OVERRIDE, /* Special: override by possession of auth token */ + KEY_DEFER_PERM_CHECK, /* Special: permission check is deferred */ +}; + struct seq_file; struct user_struct; struct signal_struct; @@ -176,6 +193,9 @@ struct key { struct list_head graveyard_link; struct rb_node serial_node; }; +#ifdef CONFIG_KEY_NOTIFICATIONS + struct watch_list *watchers; /* Entities watching this key for changes */ +#endif struct rw_semaphore sem; /* change vs change sem */ struct key_user *user; /* owner of this key */ void *security; /* security data for this key */ @@ -417,20 +437,9 @@ static inline key_serial_t key_serial(const struct key *key) extern void key_set_timeout(struct key *, unsigned); extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags, - key_perm_t perm); + enum key_need_perm need_perm); extern void key_free_user_ns(struct user_namespace *); -/* - * The permissions required on a key that we're looking up. - */ -#define KEY_NEED_VIEW 0x01 /* Require permission to view attributes */ -#define KEY_NEED_READ 0x02 /* Require permission to read content */ -#define KEY_NEED_WRITE 0x04 /* Require permission to update / modify */ -#define KEY_NEED_SEARCH 0x08 /* Require permission to search (keyring) or find (key) */ -#define KEY_NEED_LINK 0x10 /* Require permission to link */ -#define KEY_NEED_SETATTR 0x20 /* Require permission to change attributes */ -#define KEY_NEED_ALL 0x3f /* All the above permissions */ - static inline short key_read_state(const struct key *key) { /* Barrier versus mark_key_instantiated(). */ diff --git a/include/linux/lsm_audit.h b/include/linux/lsm_audit.h index 99d629fd9944..28f23b341c1c 100644 --- a/include/linux/lsm_audit.h +++ b/include/linux/lsm_audit.h @@ -75,6 +75,7 @@ struct common_audit_data { #define LSM_AUDIT_DATA_IBPKEY 13 #define LSM_AUDIT_DATA_IBENDPORT 14 #define LSM_AUDIT_DATA_LOCKDOWN 15 +#define LSM_AUDIT_DATA_NOTIFICATION 16 union { struct path path; struct dentry *dentry; diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index fb3ce6cec997..4a3d70baa7f1 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -254,6 +254,15 @@ LSM_HOOK(int, 0, inode_setsecctx, struct dentry *dentry, void *ctx, u32 ctxlen) LSM_HOOK(int, 0, inode_getsecctx, struct inode *inode, void **ctx, u32 *ctxlen) +#if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE) +LSM_HOOK(int, 0, post_notification, const struct cred *w_cred, + const struct cred *cred, struct watch_notification *n) +#endif /* CONFIG_SECURITY && CONFIG_WATCH_QUEUE */ + +#if defined(CONFIG_SECURITY) && defined(CONFIG_KEY_NOTIFICATIONS) +LSM_HOOK(int, 0, watch_key, struct key *key) +#endif /* CONFIG_SECURITY && CONFIG_KEY_NOTIFICATIONS */ + #ifdef CONFIG_SECURITY_NETWORK LSM_HOOK(int, 0, unix_stream_connect, struct sock *sock, struct sock *other, struct sock *newsk) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 3e62dab77699..73d87955e26b 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1445,6 +1445,20 @@ * @ctx is a pointer in which to place the allocated security context. * @ctxlen points to the place to put the length of @ctx. * + * Security hooks for the general notification queue: + * + * @post_notification: + * Check to see if a watch notification can be posted to a particular + * queue. + * @w_cred: The credentials of the whoever set the watch. + * @cred: The event-triggerer's credentials + * @n: The notification being posted + * + * @watch_key: + * Check to see if a process is allowed to watch for event notifications + * from a key or keyring. + * @key: The key to watch. + * * Security hooks for using the eBPF maps and programs functionalities through * eBPF syscalls. * diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 0c31b9461262..50afd0d0084c 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -9,6 +9,10 @@ #define PIPE_BUF_FLAG_GIFT 0x04 /* page is a gift */ #define PIPE_BUF_FLAG_PACKET 0x08 /* read() as a packet */ #define PIPE_BUF_FLAG_CAN_MERGE 0x10 /* can merge buffers */ +#define PIPE_BUF_FLAG_WHOLE 0x20 /* read() must return entire buffer or error */ +#ifdef CONFIG_WATCH_QUEUE +#define PIPE_BUF_FLAG_LOSS 0x40 /* Message loss happened after this buffer */ +#endif /** * struct pipe_buffer - a linux kernel pipe buffer @@ -34,8 +38,10 @@ struct pipe_buffer { * @wr_wait: writer wait point in case of full pipe * @head: The point of buffer production * @tail: The point of buffer consumption + * @note_loss: The next read() should insert a data-lost message * @max_usage: The maximum number of slots that may be used in the ring * @ring_size: total number of buffers (should be a power of 2) + * @nr_accounted: The amount this pipe accounts for in user->pipe_bufs * @tmp_page: cached released page * @readers: number of current readers of this pipe * @writers: number of current writers of this pipe @@ -46,6 +52,7 @@ struct pipe_buffer { * @fasync_writers: writer side fasync * @bufs: the circular array of pipe buffers * @user: the user who created this pipe + * @watch_queue: If this pipe is a watch_queue, this is the stuff for that **/ struct pipe_inode_info { struct mutex mutex; @@ -54,6 +61,10 @@ struct pipe_inode_info { unsigned int tail; unsigned int max_usage; unsigned int ring_size; +#ifdef CONFIG_WATCH_QUEUE + bool note_loss; +#endif + unsigned int nr_accounted; unsigned int readers; unsigned int writers; unsigned int files; @@ -64,6 +75,9 @@ struct pipe_inode_info { struct fasync_struct *fasync_writers; struct pipe_buffer *bufs; struct user_struct *user; +#ifdef CONFIG_WATCH_QUEUE + struct watch_queue *watch_queue; +#endif }; /* @@ -239,9 +253,20 @@ void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *); extern const struct pipe_buf_operations nosteal_pipe_buf_ops; +#ifdef CONFIG_WATCH_QUEUE +unsigned long account_pipe_buffers(struct user_struct *user, + unsigned long old, unsigned long new); +bool too_many_pipe_buffers_soft(unsigned long user_bufs); +bool too_many_pipe_buffers_hard(unsigned long user_bufs); +bool pipe_is_unprivileged_user(void); +#endif + /* for F_SETPIPE_SZ and F_GETPIPE_SZ */ +#ifdef CONFIG_WATCH_QUEUE +int pipe_resize_ring(struct pipe_inode_info *pipe, unsigned int nr_slots); +#endif long pipe_fcntl(struct file *, unsigned int, unsigned long arg); -struct pipe_inode_info *get_pipe_info(struct file *file); +struct pipe_inode_info *get_pipe_info(struct file *file, bool for_splice); int create_pipe_files(struct file **, int); unsigned int round_pipe_size(unsigned long size); diff --git a/include/linux/security.h b/include/linux/security.h index b3f2cb21b4f2..469fa91f8cf8 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -56,6 +56,8 @@ struct mm_struct; struct fs_context; struct fs_parameter; enum fs_value_type; +struct watch; +struct watch_notification; /* Default (no) options for the capable function */ #define CAP_OPT_NONE 0x0 @@ -1282,6 +1284,28 @@ static inline int security_locked_down(enum lockdown_reason what) } #endif /* CONFIG_SECURITY */ +#if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE) +int security_post_notification(const struct cred *w_cred, + const struct cred *cred, + struct watch_notification *n); +#else +static inline int security_post_notification(const struct cred *w_cred, + const struct cred *cred, + struct watch_notification *n) +{ + return 0; +} +#endif + +#if defined(CONFIG_SECURITY) && defined(CONFIG_KEY_NOTIFICATIONS) +int security_watch_key(struct key *key); +#else +static inline int security_watch_key(struct key *key) +{ + return 0; +} +#endif + #ifdef CONFIG_SECURITY_NETWORK int security_unix_stream_connect(struct sock *sock, struct sock *other, struct sock *newsk); @@ -1750,8 +1774,8 @@ static inline int security_path_chroot(const struct path *path) int security_key_alloc(struct key *key, const struct cred *cred, unsigned long flags); void security_key_free(struct key *key); -int security_key_permission(key_ref_t key_ref, - const struct cred *cred, unsigned perm); +int security_key_permission(key_ref_t key_ref, const struct cred *cred, + enum key_need_perm need_perm); int security_key_getsecurity(struct key *key, char **_buffer); #else @@ -1769,7 +1793,7 @@ static inline void security_key_free(struct key *key) static inline int security_key_permission(key_ref_t key_ref, const struct cred *cred, - unsigned perm) + enum key_need_perm need_perm) { return 0; } diff --git a/include/linux/watch_queue.h b/include/linux/watch_queue.h new file mode 100644 index 000000000000..5e08db2adc31 --- /dev/null +++ b/include/linux/watch_queue.h @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0 +/* User-mappable watch queue + * + * Copyright (C) 2020 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * See Documentation/watch_queue.rst + */ + +#ifndef _LINUX_WATCH_QUEUE_H +#define _LINUX_WATCH_QUEUE_H + +#include <uapi/linux/watch_queue.h> +#include <linux/kref.h> +#include <linux/rcupdate.h> + +#ifdef CONFIG_WATCH_QUEUE + +struct cred; + +struct watch_type_filter { + enum watch_notification_type type; + __u32 subtype_filter[1]; /* Bitmask of subtypes to filter on */ + __u32 info_filter; /* Filter on watch_notification::info */ + __u32 info_mask; /* Mask of relevant bits in info_filter */ +}; + +struct watch_filter { + union { + struct rcu_head rcu; + unsigned long type_filter[2]; /* Bitmask of accepted types */ + }; + u32 nr_filters; /* Number of filters */ + struct watch_type_filter filters[]; +}; + +struct watch_queue { + struct rcu_head rcu; + struct watch_filter __rcu *filter; + struct pipe_inode_info *pipe; /* The pipe we're using as a buffer */ + struct hlist_head watches; /* Contributory watches */ + struct page **notes; /* Preallocated notifications */ + unsigned long *notes_bitmap; /* Allocation bitmap for notes */ + struct kref usage; /* Object usage count */ + spinlock_t lock; + unsigned int nr_notes; /* Number of notes */ + unsigned int nr_pages; /* Number of pages in notes[] */ + bool defunct; /* T when queues closed */ +}; + +/* + * Representation of a watch on an object. + */ +struct watch { + union { + struct rcu_head rcu; + u32 info_id; /* ID to be OR'd in to info field */ + }; + struct watch_queue __rcu *queue; /* Queue to post events to */ + struct hlist_node queue_node; /* Link in queue->watches */ + struct watch_list __rcu *watch_list; + struct hlist_node list_node; /* Link in watch_list->watchers */ + const struct cred *cred; /* Creds of the owner of the watch */ + void *private; /* Private data for the watched object */ + u64 id; /* Internal identifier */ + struct kref usage; /* Object usage count */ +}; + +/* + * List of watches on an object. + */ +struct watch_list { + struct rcu_head rcu; + struct hlist_head watchers; + void (*release_watch)(struct watch *); + spinlock_t lock; +}; + +extern void __post_watch_notification(struct watch_list *, + struct watch_notification *, + const struct cred *, + u64); +extern struct watch_queue *get_watch_queue(int); +extern void put_watch_queue(struct watch_queue *); +extern void init_watch(struct watch *, struct watch_queue *); +extern int add_watch_to_object(struct watch *, struct watch_list *); +extern int remove_watch_from_object(struct watch_list *, struct watch_queue *, u64, bool); +extern long watch_queue_set_size(struct pipe_inode_info *, unsigned int); +extern long watch_queue_set_filter(struct pipe_inode_info *, + struct watch_notification_filter __user *); +extern int watch_queue_init(struct pipe_inode_info *); +extern void watch_queue_clear(struct watch_queue *); + +static inline void init_watch_list(struct watch_list *wlist, + void (*release_watch)(struct watch *)) +{ + INIT_HLIST_HEAD(&wlist->watchers); + spin_lock_init(&wlist->lock); + wlist->release_watch = release_watch; +} + +static inline void post_watch_notification(struct watch_list *wlist, + struct watch_notification *n, + const struct cred *cred, + u64 id) +{ + if (unlikely(wlist)) + __post_watch_notification(wlist, n, cred, id); +} + +static inline void remove_watch_list(struct watch_list *wlist, u64 id) +{ + if (wlist) { + remove_watch_from_object(wlist, NULL, id, true); + kfree_rcu(wlist, rcu); + } +} + +/** + * watch_sizeof - Calculate the information part of the size of a watch record, + * given the structure size. + */ +#define watch_sizeof(STRUCT) (sizeof(STRUCT) << WATCH_INFO_LENGTH__SHIFT) + +#endif + +#endif /* _LINUX_WATCH_QUEUE_H */ diff --git a/include/uapi/linux/keyctl.h b/include/uapi/linux/keyctl.h index ed3d5893830d..4c8884eea808 100644 --- a/include/uapi/linux/keyctl.h +++ b/include/uapi/linux/keyctl.h @@ -69,6 +69,7 @@ #define KEYCTL_RESTRICT_KEYRING 29 /* Restrict keys allowed to link to a keyring */ #define KEYCTL_MOVE 30 /* Move keys between keyrings */ #define KEYCTL_CAPABILITIES 31 /* Find capabilities of keyrings subsystem */ +#define KEYCTL_WATCH_KEY 32 /* Watch a key or ring of keys for changes */ /* keyctl structures */ struct keyctl_dh_params { @@ -130,5 +131,6 @@ struct keyctl_pkey_params { #define KEYCTL_CAPS0_MOVE 0x80 /* KEYCTL_MOVE supported */ #define KEYCTL_CAPS1_NS_KEYRING_NAME 0x01 /* Keyring names are per-user_namespace */ #define KEYCTL_CAPS1_NS_KEY_TAG 0x02 /* Key indexing can include a namespace tag */ +#define KEYCTL_CAPS1_NOTIFICATIONS 0x04 /* Keys generate watchable notifications */ #endif /* _LINUX_KEYCTL_H */ diff --git a/include/uapi/linux/watch_queue.h b/include/uapi/linux/watch_queue.h new file mode 100644 index 000000000000..c3d8320b5d3a --- /dev/null +++ b/include/uapi/linux/watch_queue.h @@ -0,0 +1,104 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_LINUX_WATCH_QUEUE_H +#define _UAPI_LINUX_WATCH_QUEUE_H + +#include <linux/types.h> +#include <linux/fcntl.h> +#include <linux/ioctl.h> + +#define O_NOTIFICATION_PIPE O_EXCL /* Parameter to pipe2() selecting notification pipe */ + +#define IOC_WATCH_QUEUE_SET_SIZE _IO('W', 0x60) /* Set the size in pages */ +#define IOC_WATCH_QUEUE_SET_FILTER _IO('W', 0x61) /* Set the filter */ + +enum watch_notification_type { + WATCH_TYPE_META = 0, /* Special record */ + WATCH_TYPE_KEY_NOTIFY = 1, /* Key change event notification */ + WATCH_TYPE__NR = 2 +}; + +enum watch_meta_notification_subtype { + WATCH_META_REMOVAL_NOTIFICATION = 0, /* Watched object was removed */ + WATCH_META_LOSS_NOTIFICATION = 1, /* Data loss occurred */ +}; + +/* + * Notification record header. This is aligned to 64-bits so that subclasses + * can contain __u64 fields. + */ +struct watch_notification { + __u32 type:24; /* enum watch_notification_type */ + __u32 subtype:8; /* Type-specific subtype (filterable) */ + __u32 info; +#define WATCH_INFO_LENGTH 0x0000007f /* Length of record */ +#define WATCH_INFO_LENGTH__SHIFT 0 +#define WATCH_INFO_ID 0x0000ff00 /* ID of watchpoint */ +#define WATCH_INFO_ID__SHIFT 8 +#define WATCH_INFO_TYPE_INFO 0xffff0000 /* Type-specific info */ +#define WATCH_INFO_TYPE_INFO__SHIFT 16 +#define WATCH_INFO_FLAG_0 0x00010000 /* Type-specific info, flag bit 0 */ +#define WATCH_INFO_FLAG_1 0x00020000 /* ... */ +#define WATCH_INFO_FLAG_2 0x00040000 +#define WATCH_INFO_FLAG_3 0x00080000 +#define WATCH_INFO_FLAG_4 0x00100000 +#define WATCH_INFO_FLAG_5 0x00200000 +#define WATCH_INFO_FLAG_6 0x00400000 +#define WATCH_INFO_FLAG_7 0x00800000 +}; + +/* + * Notification filtering rules (IOC_WATCH_QUEUE_SET_FILTER). + */ +struct watch_notification_type_filter { + __u32 type; /* Type to apply filter to */ + __u32 info_filter; /* Filter on watch_notification::info */ + __u32 info_mask; /* Mask of relevant bits in info_filter */ + __u32 subtype_filter[8]; /* Bitmask of subtypes to filter on */ +}; + +struct watch_notification_filter { + __u32 nr_filters; /* Number of filters */ + __u32 __reserved; /* Must be 0 */ + struct watch_notification_type_filter filters[]; +}; + + +/* + * Extended watch removal notification. This is used optionally if the type + * wants to indicate an identifier for the object being watched, if there is + * such. This can be distinguished by the length. + * + * type -> WATCH_TYPE_META + * subtype -> WATCH_META_REMOVAL_NOTIFICATION + */ +struct watch_notification_removal { + struct watch_notification watch; + __u64 id; /* Type-dependent identifier */ +}; + +/* + * Type of key/keyring change notification. + */ +enum key_notification_subtype { + NOTIFY_KEY_INSTANTIATED = 0, /* Key was instantiated (aux is error code) */ + NOTIFY_KEY_UPDATED = 1, /* Key was updated */ + NOTIFY_KEY_LINKED = 2, /* Key (aux) was added to watched keyring */ + NOTIFY_KEY_UNLINKED = 3, /* Key (aux) was removed from watched keyring */ + NOTIFY_KEY_CLEARED = 4, /* Keyring was cleared */ + NOTIFY_KEY_REVOKED = 5, /* Key was revoked */ + NOTIFY_KEY_INVALIDATED = 6, /* Key was invalidated */ + NOTIFY_KEY_SETATTR = 7, /* Key's attributes got changed */ +}; + +/* + * Key/keyring notification record. + * - watch.type = WATCH_TYPE_KEY_NOTIFY + * - watch.subtype = enum key_notification_type + */ +struct key_notification { + struct watch_notification watch; + __u32 key_id; /* The key/keyring affected */ + __u32 aux; /* Per-type auxiliary data */ +}; + +#endif /* _UAPI_LINUX_WATCH_QUEUE_H */ |