mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![David Howells](/assets/img/avatar_default.png)
Add support for per-user_namespace registers of persistent per-UID kerberos caches held within the kernel. This allows the kerberos cache to be retained beyond the life of all a user's processes so that the user's cron jobs can work. The kerberos cache is envisioned as a keyring/key tree looking something like: struct user_namespace \___ .krb_cache keyring - The register \___ _krb.0 keyring - Root's Kerberos cache \___ _krb.5000 keyring - User 5000's Kerberos cache \___ _krb.5001 keyring - User 5001's Kerberos cache \___ tkt785 big_key - A ccache blob \___ tkt12345 big_key - Another ccache blob Or possibly: struct user_namespace \___ .krb_cache keyring - The register \___ _krb.0 keyring - Root's Kerberos cache \___ _krb.5000 keyring - User 5000's Kerberos cache \___ _krb.5001 keyring - User 5001's Kerberos cache \___ tkt785 keyring - A ccache \___ krbtgt/REDHAT.COM@REDHAT.COM big_key \___ http/REDHAT.COM@REDHAT.COM user \___ afs/REDHAT.COM@REDHAT.COM user \___ nfs/REDHAT.COM@REDHAT.COM user \___ krbtgt/KERNEL.ORG@KERNEL.ORG big_key \___ http/KERNEL.ORG@KERNEL.ORG big_key What goes into a particular Kerberos cache is entirely up to userspace. Kernel support is limited to giving you the Kerberos cache keyring that you want. The user asks for their Kerberos cache by: krb_cache = keyctl_get_krbcache(uid, dest_keyring); The uid is -1 or the user's own UID for the user's own cache or the uid of some other user's cache (requires CAP_SETUID). This permits rpc.gssd or whatever to mess with the cache. The cache returned is a keyring named "_krb.<uid>" that the possessor can read, search, clear, invalidate, unlink from and add links to. Active LSMs get a chance to rule on whether the caller is permitted to make a link. Each uid's cache keyring is created when it first accessed and is given a timeout that is extended each time this function is called so that the keyring goes away after a while. The timeout is configurable by sysctl but defaults to three days. Each user_namespace struct gets a lazily-created keyring that serves as the register. The cache keyrings are added to it. This means that standard key search and garbage collection facilities are available. The user_namespace struct's register goes away when it does and anything left in it is then automatically gc'd. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Simo Sorce <simo@redhat.com> cc: Serge E. Hallyn <serge.hallyn@ubuntu.com> cc: Eric W. Biederman <ebiederm@xmission.com>
286 lines
9.4 KiB
C
286 lines
9.4 KiB
C
/* Authentication token and access key management internal defs
|
|
*
|
|
* Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.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; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _INTERNAL_H
|
|
#define _INTERNAL_H
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/key-type.h>
|
|
#include <linux/task_work.h>
|
|
|
|
struct iovec;
|
|
|
|
#ifdef __KDEBUG
|
|
#define kenter(FMT, ...) \
|
|
printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
|
|
#define kleave(FMT, ...) \
|
|
printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
|
|
#define kdebug(FMT, ...) \
|
|
printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
|
|
#else
|
|
#define kenter(FMT, ...) \
|
|
no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
|
|
#define kleave(FMT, ...) \
|
|
no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
|
|
#define kdebug(FMT, ...) \
|
|
no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
|
|
#endif
|
|
|
|
extern struct key_type key_type_dead;
|
|
extern struct key_type key_type_user;
|
|
extern struct key_type key_type_logon;
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* Keep track of keys for a user.
|
|
*
|
|
* This needs to be separate to user_struct to avoid a refcount-loop
|
|
* (user_struct pins some keyrings which pin this struct).
|
|
*
|
|
* We also keep track of keys under request from userspace for this UID here.
|
|
*/
|
|
struct key_user {
|
|
struct rb_node node;
|
|
struct mutex cons_lock; /* construction initiation lock */
|
|
spinlock_t lock;
|
|
atomic_t usage; /* for accessing qnkeys & qnbytes */
|
|
atomic_t nkeys; /* number of keys */
|
|
atomic_t nikeys; /* number of instantiated keys */
|
|
kuid_t uid;
|
|
int qnkeys; /* number of keys allocated to this user */
|
|
int qnbytes; /* number of bytes allocated to this user */
|
|
};
|
|
|
|
extern struct rb_root key_user_tree;
|
|
extern spinlock_t key_user_lock;
|
|
extern struct key_user root_key_user;
|
|
|
|
extern struct key_user *key_user_lookup(kuid_t uid);
|
|
extern void key_user_put(struct key_user *user);
|
|
|
|
/*
|
|
* Key quota limits.
|
|
* - root has its own separate limits to everyone else
|
|
*/
|
|
extern unsigned key_quota_root_maxkeys;
|
|
extern unsigned key_quota_root_maxbytes;
|
|
extern unsigned key_quota_maxkeys;
|
|
extern unsigned key_quota_maxbytes;
|
|
|
|
#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
|
|
|
|
|
|
extern struct kmem_cache *key_jar;
|
|
extern struct rb_root key_serial_tree;
|
|
extern spinlock_t key_serial_lock;
|
|
extern struct mutex key_construction_mutex;
|
|
extern wait_queue_head_t request_key_conswq;
|
|
|
|
|
|
extern struct key_type *key_type_lookup(const char *type);
|
|
extern void key_type_put(struct key_type *ktype);
|
|
|
|
extern int __key_link_begin(struct key *keyring,
|
|
const struct keyring_index_key *index_key,
|
|
struct assoc_array_edit **_edit);
|
|
extern int __key_link_check_live_key(struct key *keyring, struct key *key);
|
|
extern void __key_link(struct key *key, struct assoc_array_edit **_edit);
|
|
extern void __key_link_end(struct key *keyring,
|
|
const struct keyring_index_key *index_key,
|
|
struct assoc_array_edit *edit);
|
|
|
|
extern key_ref_t find_key_to_update(key_ref_t keyring_ref,
|
|
const struct keyring_index_key *index_key);
|
|
|
|
extern struct key *keyring_search_instkey(struct key *keyring,
|
|
key_serial_t target_id);
|
|
|
|
extern int iterate_over_keyring(const struct key *keyring,
|
|
int (*func)(const struct key *key, void *data),
|
|
void *data);
|
|
|
|
typedef int (*key_match_func_t)(const struct key *, const void *);
|
|
|
|
struct keyring_search_context {
|
|
struct keyring_index_key index_key;
|
|
const struct cred *cred;
|
|
key_match_func_t match;
|
|
const void *match_data;
|
|
unsigned flags;
|
|
#define KEYRING_SEARCH_LOOKUP_TYPE 0x0001 /* [as type->def_lookup_type] */
|
|
#define KEYRING_SEARCH_NO_STATE_CHECK 0x0002 /* Skip state checks */
|
|
#define KEYRING_SEARCH_DO_STATE_CHECK 0x0004 /* Override NO_STATE_CHECK */
|
|
#define KEYRING_SEARCH_NO_UPDATE_TIME 0x0008 /* Don't update times */
|
|
#define KEYRING_SEARCH_NO_CHECK_PERM 0x0010 /* Don't check permissions */
|
|
#define KEYRING_SEARCH_DETECT_TOO_DEEP 0x0020 /* Give an error on excessive depth */
|
|
|
|
int (*iterator)(const void *object, void *iterator_data);
|
|
|
|
/* Internal stuff */
|
|
int skipped_ret;
|
|
bool possessed;
|
|
key_ref_t result;
|
|
struct timespec now;
|
|
};
|
|
|
|
extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
|
|
struct keyring_search_context *ctx);
|
|
|
|
extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
|
|
extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
|
|
|
|
extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
|
|
|
|
extern int install_user_keyrings(void);
|
|
extern int install_thread_keyring_to_cred(struct cred *);
|
|
extern int install_process_keyring_to_cred(struct cred *);
|
|
extern int install_session_keyring_to_cred(struct cred *, struct key *);
|
|
|
|
extern struct key *request_key_and_link(struct key_type *type,
|
|
const char *description,
|
|
const void *callout_info,
|
|
size_t callout_len,
|
|
void *aux,
|
|
struct key *dest_keyring,
|
|
unsigned long flags);
|
|
|
|
extern int lookup_user_key_possessed(const struct key *key, const void *target);
|
|
extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
|
|
key_perm_t perm);
|
|
#define KEY_LOOKUP_CREATE 0x01
|
|
#define KEY_LOOKUP_PARTIAL 0x02
|
|
#define KEY_LOOKUP_FOR_UNLINK 0x04
|
|
|
|
extern long join_session_keyring(const char *name);
|
|
extern void key_change_session_keyring(struct callback_head *twork);
|
|
|
|
extern struct work_struct key_gc_work;
|
|
extern unsigned key_gc_delay;
|
|
extern void keyring_gc(struct key *keyring, time_t limit);
|
|
extern void key_schedule_gc(time_t gc_at);
|
|
extern void key_schedule_gc_links(void);
|
|
extern void key_gc_keytype(struct key_type *ktype);
|
|
|
|
extern int key_task_permission(const key_ref_t key_ref,
|
|
const struct cred *cred,
|
|
key_perm_t perm);
|
|
|
|
/*
|
|
* Check to see whether permission is granted to use a key in the desired way.
|
|
*/
|
|
static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
|
|
{
|
|
return key_task_permission(key_ref, current_cred(), perm);
|
|
}
|
|
|
|
/* required permissions */
|
|
#define KEY_VIEW 0x01 /* require permission to view attributes */
|
|
#define KEY_READ 0x02 /* require permission to read content */
|
|
#define KEY_WRITE 0x04 /* require permission to update / modify */
|
|
#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
|
|
#define KEY_LINK 0x10 /* require permission to link */
|
|
#define KEY_SETATTR 0x20 /* require permission to change attributes */
|
|
#define KEY_ALL 0x3f /* all the above permissions */
|
|
|
|
/*
|
|
* Authorisation record for request_key().
|
|
*/
|
|
struct request_key_auth {
|
|
struct key *target_key;
|
|
struct key *dest_keyring;
|
|
const struct cred *cred;
|
|
void *callout_info;
|
|
size_t callout_len;
|
|
pid_t pid;
|
|
};
|
|
|
|
extern struct key_type key_type_request_key_auth;
|
|
extern struct key *request_key_auth_new(struct key *target,
|
|
const void *callout_info,
|
|
size_t callout_len,
|
|
struct key *dest_keyring);
|
|
|
|
extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
|
|
|
|
/*
|
|
* Determine whether a key is dead.
|
|
*/
|
|
static inline bool key_is_dead(const struct key *key, time_t limit)
|
|
{
|
|
return
|
|
key->flags & ((1 << KEY_FLAG_DEAD) |
|
|
(1 << KEY_FLAG_INVALIDATED)) ||
|
|
(key->expiry > 0 && key->expiry <= limit);
|
|
}
|
|
|
|
/*
|
|
* keyctl() functions
|
|
*/
|
|
extern long keyctl_get_keyring_ID(key_serial_t, int);
|
|
extern long keyctl_join_session_keyring(const char __user *);
|
|
extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
|
|
extern long keyctl_revoke_key(key_serial_t);
|
|
extern long keyctl_keyring_clear(key_serial_t);
|
|
extern long keyctl_keyring_link(key_serial_t, key_serial_t);
|
|
extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
|
|
extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
|
|
extern long keyctl_keyring_search(key_serial_t, const char __user *,
|
|
const char __user *, key_serial_t);
|
|
extern long keyctl_read_key(key_serial_t, char __user *, size_t);
|
|
extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
|
|
extern long keyctl_setperm_key(key_serial_t, key_perm_t);
|
|
extern long keyctl_instantiate_key(key_serial_t, const void __user *,
|
|
size_t, key_serial_t);
|
|
extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
|
|
extern long keyctl_set_reqkey_keyring(int);
|
|
extern long keyctl_set_timeout(key_serial_t, unsigned);
|
|
extern long keyctl_assume_authority(key_serial_t);
|
|
extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
|
|
size_t buflen);
|
|
extern long keyctl_session_to_parent(void);
|
|
extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
|
|
extern long keyctl_instantiate_key_iov(key_serial_t,
|
|
const struct iovec __user *,
|
|
unsigned, key_serial_t);
|
|
extern long keyctl_invalidate_key(key_serial_t);
|
|
|
|
extern long keyctl_instantiate_key_common(key_serial_t,
|
|
const struct iovec *,
|
|
unsigned, size_t, key_serial_t);
|
|
#ifdef CONFIG_PERSISTENT_KEYRINGS
|
|
extern long keyctl_get_persistent(uid_t, key_serial_t);
|
|
extern unsigned persistent_keyring_expiry;
|
|
#else
|
|
static inline long keyctl_get_persistent(uid_t uid, key_serial_t destring)
|
|
{
|
|
return -EOPNOTSUPP;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Debugging key validation
|
|
*/
|
|
#ifdef KEY_DEBUGGING
|
|
extern void __key_check(const struct key *);
|
|
|
|
static inline void key_check(const struct key *key)
|
|
{
|
|
if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
|
|
__key_check(key);
|
|
}
|
|
|
|
#else
|
|
|
|
#define key_check(key) do {} while(0)
|
|
|
|
#endif
|
|
|
|
#endif /* _INTERNAL_H */
|