diff options
46 files changed, 992 insertions, 325 deletions
diff --git a/Documentation/security/keys/core.rst b/Documentation/security/keys/core.rst index 0e74f372e58c..1b3c907980ad 100644 --- a/Documentation/security/keys/core.rst +++ b/Documentation/security/keys/core.rst @@ -57,9 +57,9 @@ Each key has a number of attributes: type provides an operation to perform a match between the description on a key and a criterion string. - * Each key has an owner user ID, a group ID and a permissions mask. These - are used to control what a process may do to a key from userspace, and - whether a kernel service will be able to find the key. + * Each key has an owner user ID, a group ID and an ACL. These are used to + control what a process may do to a key from userspace, and whether a + kernel service will be able to find the key. * Each key can be set to expire at a specific time by the key type's instantiation function. Keys can also be immortal. @@ -198,43 +198,110 @@ The key service provides a number of features besides keys: Key Access Permissions ====================== -Keys have an owner user ID, a group access ID, and a permissions mask. The mask -has up to eight bits each for possessor, user, group and other access. Only -six of each set of eight bits are defined. These permissions granted are: +Keys have an owner user ID, a group ID and an ACL. The ACL is made up of a +sequence of ACEs that each contain three elements: - * View + * The type of subject. + * The subject. - This permits a key or keyring's attributes to be viewed - including key - type and description. + These two together indicate the subject to whom the permits are granted. + The type can be one of: - * Read + * ``KEY_ACE_SUBJ_STANDARD`` - This permits a key's payload to be viewed or a keyring's list of linked - keys. + The subject is a standard 'macro' type. The subject can be one of: + + * ``KEY_ACE_EVERYONE`` + + The permits are granted to everyone. It replaces the old 'other' + type on the assumption that you wouldn't grant a permission to other + that you you wouldn't grant to everyone else. + + * ``KEY_ACE_OWNER`` + + The permits are granted to the owner of the key (key->uid). + + * ``KEY_ACE_GROUP`` + + The permits are granted to the key's group (key->gid). + + * ``KEY_ACE_POSSESSOR`` + + The permits are granted to anyone who possesses the key. + + * The set of permits granted to the subject. These include: + + * ``KEY_ACE_VIEW`` + + This permits a key or keyring's attributes to be viewed - including the + key type and description. + + * ``KEY_ACE_READ`` + + This permits a key's payload to be viewed or a keyring's list of linked + keys. - * Write + * ``KEY_ACE_WRITE`` - This permits a key's payload to be instantiated or updated, or it allows a - link to be added to or removed from a keyring. + This permits a key's payload to be instantiated or updated, or it allows + a link to be added to or removed from a keyring. - * Search + * ``KEY_ACE_SEARCH`` - This permits keyrings to be searched and keys to be found. Searches can - only recurse into nested keyrings that have search permission set. + This permits keyrings to be searched and keys to be found. Searches can + only recurse into nested keyrings that have search permission set. - * Link + * ``KEY_ACE_LINK`` - This permits a key or keyring to be linked to. To create a link from a - keyring to a key, a process must have Write permission on the keyring and - Link permission on the key. + This permits a key or keyring to be linked to. To create a link from a + keyring to a key, a process must have Write permission on the keyring + and Link permission on the key. - * Set Attribute + * ``KEY_ACE_SET_SECURITY`` - This permits a key's UID, GID and permissions mask to be changed. + This permits a key's UID, GID and permissions mask to be changed. + + * ``KEY_ACE_INVAL`` + + This permits a key to be invalidated with KEYCTL_INVALIDATE. + + * ``KEY_ACE_REVOKE`` + + This permits a key to be revoked with KEYCTL_REVOKE. + + * ``KEY_ACE_JOIN`` + + This permits a keyring to be joined as a session by + KEYCTL_JOIN_SESSION_KEYRING or KEYCTL_SESSION_TO_PARENT. + + * ``KEY_ACE_CLEAR`` + + This permits a keyring to be cleared. For changing the ownership, group ID or permissions mask, being the owner of the key or having the sysadmin capability is sufficient. +The legacy KEYCTL_SETPERM and KEYCTL_DESCRIBE functions can only see/generate +View, Read, Write, Search, Link and SetAttr permits, and do this for each of +possessor, user, group and other permission sets as a 32-bit flag mask. These +will be approximated/inferred: + + SETPERM Permit Implied ACE Permit + =============== ======================= + Search Inval, Join + Write Revoke, Clear + Setattr Set Security, Revoke + + ACE Permit Described as + =============== ======================= + Inval Search + Join Search + Revoke Write (unless Setattr) + Clear write + Set Security Setattr + +'Other' will be approximated as/inferred from the 'Everyone' subject. + SELinux Support =============== @@ -1084,7 +1151,8 @@ payload contents" for more information. struct key *request_key(const struct key_type *type, const char *description, - const char *callout_info); + const char *callout_info, + struct key_acl *acl); This is used to request a key or keyring with a description that matches the description specified according to the key type's match_preparse() @@ -1099,6 +1167,8 @@ payload contents" for more information. If successful, the key will have been attached to the default keyring for implicitly obtained request-key keys, as set by KEYCTL_SET_REQKEY_KEYRING. + If a key is created, it will be given the specified ACL. + See also Documentation/security/keys/request-key.rst. @@ -1107,7 +1177,8 @@ payload contents" for more information. struct key *request_key_tag(const struct key_type *type, const char *description, struct key_tag *domain_tag, - const char *callout_info); + const char *callout_info, + struct key_acl *acl); This is identical to request_key(), except that a domain tag may be specifies that causes search algorithm to only match keys matching that @@ -1122,7 +1193,8 @@ payload contents" for more information. struct key_tag *domain_tag, const void *callout_info, size_t callout_len, - void *aux); + void *aux, + struct key_acl *acl); This is identical to request_key_tag(), except that the auxiliary data is passed to the key_type->request_key() op if it exists, and the @@ -1195,7 +1267,7 @@ payload contents" for more information. struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, const struct cred *cred, - key_perm_t perm, + struct key_acl *acl, struct key_restriction *restrict_link, unsigned long flags, struct key *dest); diff --git a/Documentation/security/keys/request-key.rst b/Documentation/security/keys/request-key.rst index 35f2296b704a..f356fd06c8d5 100644 --- a/Documentation/security/keys/request-key.rst +++ b/Documentation/security/keys/request-key.rst @@ -11,14 +11,16 @@ The process starts by either the kernel requesting a service by calling struct key *request_key(const struct key_type *type, const char *description, - const char *callout_info); + const char *callout_info, + struct key_acl *acl); or:: struct key *request_key_tag(const struct key_type *type, const char *description, const struct key_tag *domain_tag, - const char *callout_info); + const char *callout_info, + struct key_acl *acl); or:: @@ -27,7 +29,8 @@ or:: const struct key_tag *domain_tag, const char *callout_info, size_t callout_len, - void *aux); + void *aux, + struct key_acl *acl); or:: diff --git a/certs/blacklist.c b/certs/blacklist.c index ec00bf337eb6..93d70b885f8e 100644 --- a/certs/blacklist.c +++ b/certs/blacklist.c @@ -89,8 +89,7 @@ int mark_hash_blacklisted(const char *hash) hash, NULL, 0, - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW), + &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_BUILT_IN); if (IS_ERR(key)) { @@ -149,9 +148,7 @@ static int __init blacklist_init(void) keyring_alloc(".blacklist", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ | - KEY_USR_SEARCH, + &internal_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA | KEY_FLAG_KEEP, NULL, NULL); diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 1eba08a1af82..57be78b5fdfc 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -99,9 +99,7 @@ static __init int system_trusted_keyring_init(void) builtin_trusted_keys = keyring_alloc(".builtin_trusted_keys", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH), - KEY_ALLOC_NOT_IN_QUOTA, + &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(builtin_trusted_keys)) panic("Can't allocate builtin trusted keyring\n"); @@ -110,10 +108,7 @@ static __init int system_trusted_keyring_init(void) secondary_trusted_keys = keyring_alloc(".secondary_trusted_keys", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH | - KEY_USR_WRITE), - KEY_ALLOC_NOT_IN_QUOTA, + &internal_writable_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, get_builtin_and_secondary_restriction(), NULL); if (IS_ERR(secondary_trusted_keys)) @@ -163,8 +158,7 @@ static __init int load_system_certificate_list(void) NULL, p, plen, - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), + &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_BUILT_IN | KEY_ALLOC_BYPASS_RESTRICTION); diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 1b16d34bb785..0fd3ca9bfe54 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -2035,7 +2035,7 @@ static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string return -ENOMEM; key = request_key(key_string[0] == 'l' ? &key_type_logon : &key_type_user, - key_desc + 1, NULL); + key_desc + 1, NULL, NULL); if (IS_ERR(key)) { kzfree(new_key_string); return PTR_ERR(key); diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c index a570f2263a42..99a5708b37e3 100644 --- a/drivers/nvdimm/security.c +++ b/drivers/nvdimm/security.c @@ -55,7 +55,7 @@ static struct key *nvdimm_request_key(struct nvdimm *nvdimm) struct device *dev = &nvdimm->dev; sprintf(desc, "%s%s", NVDIMM_PREFIX, nvdimm->dimm_id); - key = request_key(&key_type_encrypted, desc, ""); + key = request_key(&key_type_encrypted, desc, "", NULL); if (IS_ERR(key)) { if (PTR_ERR(key) == -ENOKEY) dev_dbg(dev, "request_key() found no key\n"); diff --git a/fs/afs/security.c b/fs/afs/security.c index 71e71c07568f..8866703b2e6c 100644 --- a/fs/afs/security.c +++ b/fs/afs/security.c @@ -28,7 +28,7 @@ struct key *afs_request_key(struct afs_cell *cell) _debug("key %s", cell->anonymous_key->description); key = request_key(&key_type_rxrpc, cell->anonymous_key->description, - NULL); + NULL, NULL); if (IS_ERR(key)) { if (PTR_ERR(key) != -ENOKEY) { _leave(" = %ld", PTR_ERR(key)); diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c index 7f01c6e60791..d1b439ad0f1a 100644 --- a/fs/cifs/cifs_spnego.c +++ b/fs/cifs/cifs_spnego.c @@ -32,6 +32,25 @@ #include "cifsproto.h" static const struct cred *spnego_cred; +static struct key_acl cifs_spnego_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + +static struct key_acl cifs_spnego_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_CLEAR), + } +}; + /* create a new cifs key */ static int cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep) @@ -170,7 +189,8 @@ cifs_get_spnego_key(struct cifs_ses *sesInfo) cifs_dbg(FYI, "key description = %s\n", description); saved_cred = override_creds(spnego_cred); - spnego_key = request_key(&cifs_spnego_key_type, description, ""); + spnego_key = request_key(&cifs_spnego_key_type, description, "", + &cifs_spnego_key_acl); revert_creds(saved_cred); #ifdef CONFIG_CIFS_DEBUG2 @@ -207,8 +227,7 @@ init_cifs_spnego(void) keyring = keyring_alloc(".cifs_spnego", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ, + &cifs_spnego_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c index 1d377b7f2860..78eed72f3af0 100644 --- a/fs/cifs/cifsacl.c +++ b/fs/cifs/cifsacl.c @@ -33,6 +33,25 @@ #include "cifsproto.h" #include "cifs_debug.h" +static struct key_acl cifs_idmap_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + +static struct key_acl cifs_idmap_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + /* security id for everyone/world system group */ static const struct cifs_sid sid_everyone = { 1, 1, {0, 0, 0, 0, 0, 1}, {0} }; @@ -298,7 +317,8 @@ id_to_sid(unsigned int cid, uint sidtype, struct cifs_sid *ssid) rc = 0; saved_cred = override_creds(root_cred); - sidkey = request_key(&cifs_idmap_key_type, desc, ""); + sidkey = request_key(&cifs_idmap_key_type, desc, "", + &cifs_idmap_key_acl); if (IS_ERR(sidkey)) { rc = -EINVAL; cifs_dbg(FYI, "%s: Can't map %cid %u to a SID\n", @@ -403,7 +423,8 @@ try_upcall_to_get_id: return -ENOMEM; saved_cred = override_creds(root_cred); - sidkey = request_key(&cifs_idmap_key_type, sidstr, ""); + sidkey = request_key(&cifs_idmap_key_type, sidstr, "", + &cifs_idmap_key_acl); if (IS_ERR(sidkey)) { rc = -EINVAL; cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n", @@ -481,8 +502,7 @@ init_cifs_idmap(void) keyring = keyring_alloc(".cifs_idmap", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ, + &cifs_idmap_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 8dd6637a3cbb..93f7082daf52 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -2992,7 +2992,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses) } cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc); - key = request_key(&key_type_logon, desc, ""); + key = request_key(&key_type_logon, desc, "", NULL); if (IS_ERR(key)) { if (!ses->domainName) { cifs_dbg(FYI, "domainName is NULL\n"); @@ -3003,7 +3003,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses) /* didn't work, try to find a domain key */ sprintf(desc, "cifs:d:%s", ses->domainName); cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc); - key = request_key(&key_type_logon, desc, ""); + key = request_key(&key_type_logon, desc, "", NULL); if (IS_ERR(key)) { rc = PTR_ERR(key); goto out_err; diff --git a/fs/crypto/keyinfo.c b/fs/crypto/keyinfo.c index dcd91a3fbe49..4f85af8ab239 100644 --- a/fs/crypto/keyinfo.c +++ b/fs/crypto/keyinfo.c @@ -92,7 +92,7 @@ find_and_lock_process_key(const char *prefix, if (!description) return ERR_PTR(-ENOMEM); - key = request_key(&key_type_logon, description, NULL); + key = request_key(&key_type_logon, description, NULL, NULL); kfree(description); if (IS_ERR(key)) return key; diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 1c1a56be7ea2..67844fe41a61 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -91,7 +91,7 @@ ecryptfs_get_encrypted_key_payload_data(struct key *key) static inline struct key *ecryptfs_get_encrypted_key(char *sig) { - return request_key(&key_type_encrypted, sig, NULL); + return request_key(&key_type_encrypted, sig, NULL, NULL); } #else diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c index 9536e592e25a..ba382f135918 100644 --- a/fs/ecryptfs/keystore.c +++ b/fs/ecryptfs/keystore.c @@ -1610,7 +1610,7 @@ int ecryptfs_keyring_auth_tok_for_sig(struct key **auth_tok_key, { int rc = 0; - (*auth_tok_key) = request_key(&key_type_user, sig, NULL); + (*auth_tok_key) = request_key(&key_type_user, sig, NULL, NULL); if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) { (*auth_tok_key) = ecryptfs_get_encrypted_key(sig); if (!(*auth_tok_key) || IS_ERR(*auth_tok_key)) { diff --git a/fs/fscache/object-list.c b/fs/fscache/object-list.c index 72ebfe578f40..67b7bda5647a 100644 --- a/fs/fscache/object-list.c +++ b/fs/fscache/object-list.c @@ -317,7 +317,7 @@ static void fscache_objlist_config(struct fscache_objlist_data *data) const char *buf; int len; - key = request_key(&key_type_user, "fscache:objlist", NULL); + key = request_key(&key_type_user, "fscache:objlist", NULL, NULL); if (IS_ERR(key)) goto no_config; diff --git a/fs/nfs/nfs4idmap.c b/fs/nfs/nfs4idmap.c index 1e7296395d71..69679f4f2e6c 100644 --- a/fs/nfs/nfs4idmap.c +++ b/fs/nfs/nfs4idmap.c @@ -72,6 +72,25 @@ struct idmap { const struct cred *cred; }; +static struct key_acl nfs_idmap_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + +static struct key_acl nfs_idmap_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + static struct user_namespace *idmap_userns(const struct idmap *idmap) { if (idmap && idmap->cred) @@ -208,8 +227,7 @@ int nfs_idmap_init(void) keyring = keyring_alloc(".id_resolver", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ, + &nfs_idmap_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); @@ -287,11 +305,13 @@ static struct key *nfs_idmap_request_key(const char *name, size_t namelen, return ERR_PTR(ret); if (!idmap->cred || idmap->cred->user_ns == &init_user_ns) - rkey = request_key(&key_type_id_resolver, desc, ""); + rkey = request_key(&key_type_id_resolver, desc, "", + &nfs_idmap_key_acl); if (IS_ERR(rkey)) { mutex_lock(&idmap->idmap_mutex); rkey = request_key_with_auxdata(&key_type_id_resolver_legacy, - desc, NULL, "", 0, idmap); + desc, NULL, "", 0, idmap, + &nfs_idmap_key_acl); mutex_unlock(&idmap->idmap_mutex); } if (!IS_ERR(rkey)) @@ -320,8 +340,6 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen, } rcu_read_lock(); - rkey->perm |= KEY_USR_VIEW; - ret = key_validate(rkey); if (ret < 0) goto out_up; diff --git a/fs/ubifs/auth.c b/fs/ubifs/auth.c index 60f43b93d06e..38718026ad0b 100644 --- a/fs/ubifs/auth.c +++ b/fs/ubifs/auth.c @@ -227,7 +227,7 @@ int ubifs_init_authentication(struct ubifs_info *c) snprintf(hmac_name, CRYPTO_MAX_ALG_NAME, "hmac(%s)", c->auth_hash_name); - keyring_key = request_key(&key_type_logon, c->auth_key_name, NULL); + keyring_key = request_key(&key_type_logon, c->auth_key_name, NULL, NULL); if (IS_ERR(keyring_key)) { ubifs_err(c, "Failed to request key: %ld", diff --git a/include/linux/key.h b/include/linux/key.h index 91f391cd272e..6fef6684501f 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -27,49 +27,14 @@ /* key handle serial number */ typedef int32_t key_serial_t; -/* key handle permissions mask */ -typedef uint32_t key_perm_t; - struct key; struct net; #ifdef CONFIG_KEYS -#undef KEY_DEBUGGING +#include <linux/keyctl.h> -#define KEY_POS_VIEW 0x01000000 /* possessor can view a key's attributes */ -#define KEY_POS_READ 0x02000000 /* possessor can read key payload / view keyring */ -#define KEY_POS_WRITE 0x04000000 /* possessor can update key payload / add link to keyring */ -#define KEY_POS_SEARCH 0x08000000 /* possessor can find a key in search / search a keyring */ -#define KEY_POS_LINK 0x10000000 /* possessor can create a link to a key/keyring */ -#define KEY_POS_SETATTR 0x20000000 /* possessor can set key attributes */ -#define KEY_POS_ALL 0x3f000000 - -#define KEY_USR_VIEW 0x00010000 /* user permissions... */ -#define KEY_USR_READ 0x00020000 -#define KEY_USR_WRITE 0x00040000 -#define KEY_USR_SEARCH 0x00080000 -#define KEY_USR_LINK 0x00100000 -#define KEY_USR_SETATTR 0x00200000 -#define KEY_USR_ALL 0x003f0000 - -#define KEY_GRP_VIEW 0x00000100 /* group permissions... */ -#define KEY_GRP_READ 0x00000200 -#define KEY_GRP_WRITE 0x00000400 -#define KEY_GRP_SEARCH 0x00000800 -#define KEY_GRP_LINK 0x00001000 -#define KEY_GRP_SETATTR 0x00002000 -#define KEY_GRP_ALL 0x00003f00 - -#define KEY_OTH_VIEW 0x00000001 /* third party permissions... */ -#define KEY_OTH_READ 0x00000002 -#define KEY_OTH_WRITE 0x00000004 -#define KEY_OTH_SEARCH 0x00000008 -#define KEY_OTH_LINK 0x00000010 -#define KEY_OTH_SETATTR 0x00000020 -#define KEY_OTH_ALL 0x0000003f - -#define KEY_PERM_UNDEF 0xffffffff +#undef KEY_DEBUGGING struct seq_file; struct user_struct; @@ -113,6 +78,36 @@ union key_payload { void *data[4]; }; +struct key_ace { + unsigned int type; + unsigned int perm; + union { + kuid_t uid; + kgid_t gid; + unsigned int subject_id; + }; +}; + +struct key_acl { + refcount_t usage; + unsigned short nr_ace; + bool possessor_viewable; + struct rcu_head rcu; + struct key_ace aces[]; +}; + +#define KEY_POSSESSOR_ACE(perms) { \ + .type = KEY_ACE_SUBJ_STANDARD, \ + .perm = perms, \ + .subject_id = KEY_ACE_POSSESSOR \ + } + +#define KEY_OWNER_ACE(perms) { \ + .type = KEY_ACE_SUBJ_STANDARD, \ + .perm = perms, \ + .subject_id = KEY_ACE_OWNER \ + } + /*****************************************************************************/ /* * key reference with possession attribute handling @@ -179,6 +174,7 @@ struct key { struct rw_semaphore sem; /* change vs change sem */ struct key_user *user; /* owner of this key */ void *security; /* security data for this key */ + struct key_acl __rcu *acl; union { time64_t expiry; /* time at which key expires (or 0) */ time64_t revoked_at; /* time at which key was revoked */ @@ -186,7 +182,6 @@ struct key { time64_t last_used_at; /* last time used for LRU keyring discard */ kuid_t uid; kgid_t gid; - key_perm_t perm; /* access permissions */ unsigned short quotalen; /* length added to quota */ unsigned short datalen; /* payload data length * - may not match RCU dereferenced payload @@ -210,6 +205,7 @@ struct key { #define KEY_FLAG_ROOT_CAN_INVAL 7 /* set if key can be invalidated by root without permission */ #define KEY_FLAG_KEEP 8 /* set if key should not be removed */ #define KEY_FLAG_UID_KEYRING 9 /* set if key is a user or user session keyring */ +#define KEY_FLAG_HAS_ACL 10 /* Set if KEYCTL_SETACL called on key */ /* the key type and key description string * - the desc is used to match a key against search criteria @@ -258,7 +254,7 @@ extern struct key *key_alloc(struct key_type *type, const char *desc, kuid_t uid, kgid_t gid, const struct cred *cred, - key_perm_t perm, + struct key_acl *acl, unsigned long flags, struct key_restriction *restrict_link); @@ -295,7 +291,8 @@ static inline void key_ref_put(key_ref_t key_ref) extern struct key *request_key_tag(struct key_type *type, const char *description, struct key_tag *domain_tag, - const char *callout_info); + const char *callout_info, + struct key_acl *acl); extern struct key *request_key_rcu(struct key_type *type, const char *description, @@ -306,21 +303,24 @@ extern struct key *request_key_with_auxdata(struct key_type *type, struct key_tag *domain_tag, const void *callout_info, size_t callout_len, - void *aux); + void *aux, + struct key_acl *acl); /** * request_key - Request a key and wait for construction * @type: Type of key. * @description: The searchable description of the key. * @callout_info: The data to pass to the instantiation upcall (or NULL). + * @acl: The ACL to attach to a new key (or NULL). * * As for request_key_tag(), but with the default global domain tag. */ static inline struct key *request_key(struct key_type *type, const char *description, - const char *callout_info) + const char *callout_info, + struct key_acl *acl) { - return request_key_tag(type, description, NULL, callout_info); + return request_key_tag(type, description, NULL, callout_info, acl); } #ifdef CONFIG_NET @@ -330,6 +330,7 @@ static inline struct key *request_key(struct key_type *type, * @description: The searchable description of the key. * @net: The network namespace that is the key's domain of operation. * @callout_info: The data to pass to the instantiation upcall (or NULL). + * @acl: The ACL to attach to a new key (or NULL). * * As for request_key() except that it does not add the returned key to a * keyring if found, new keys are always allocated in the user's quota, the @@ -339,8 +340,8 @@ static inline struct key *request_key(struct key_type *type, * Furthermore, it then works as wait_for_key_construction() to wait for the * completion of keys undergoing construction with a non-interruptible wait. */ -#define request_key_net(type, description, net, callout_info) \ - request_key_tag(type, description, net->key_domain, callout_info); +#define request_key_net(type, description, net, callout_info, acl) \ + request_key_tag(type, description, net->key_domain, callout_info, acl); #endif /* CONFIG_NET */ extern int wait_for_key_construction(struct key *key, bool intr); @@ -352,7 +353,7 @@ extern key_ref_t key_create_or_update(key_ref_t keyring, const char *description, const void *payload, size_t plen, - key_perm_t perm, + struct key_acl *acl, unsigned long flags); extern int key_update(key_ref_t key, @@ -372,7 +373,7 @@ extern int key_unlink(struct key *keyring, extern struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, const struct cred *cred, - key_perm_t perm, + struct key_acl *acl, unsigned long flags, struct key_restriction *restrict_link, struct key *dest); @@ -405,19 +406,29 @@ 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); + u32 desired_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 */ +#define KEY_NEED_VIEW 0x001 /* Require permission to view attributes */ +#define KEY_NEED_READ 0x002 /* Require permission to read content */ +#define KEY_NEED_WRITE 0x004 /* Require permission to update / modify */ +#define KEY_NEED_SEARCH 0x008 /* Require permission to search (keyring) or find (key) */ +#define KEY_NEED_LINK 0x010 /* Require permission to link */ +#define KEY_NEED_SETSEC 0x020 /* Require permission to set owner, group, ACL */ +#define KEY_NEED_INVAL 0x040 /* Require permission to invalidate key */ +#define KEY_NEED_REVOKE 0x080 /* Require permission to revoke key */ +#define KEY_NEED_JOIN 0x100 /* Require permission to join keyring as session */ +#define KEY_NEED_CLEAR 0x200 /* Require permission to clear a keyring */ +#define KEY_NEED_ALL 0x3ff + +#define OLD_KEY_NEED_SETATTR 0x20 /* Used to be Require permission to change attributes */ + +extern struct key_acl internal_key_acl; +extern struct key_acl internal_keyring_acl; +extern struct key_acl internal_writable_keyring_acl; static inline short key_read_state(const struct key *key) { diff --git a/include/uapi/linux/keyctl.h b/include/uapi/linux/keyctl.h index ed3d5893830d..1f7a4e737214 100644 --- a/include/uapi/linux/keyctl.h +++ b/include/uapi/linux/keyctl.h @@ -15,6 +15,69 @@ #include <linux/types.h> +/* + * Keyring permission grant definitions + */ +enum key_ace_subject_type { + KEY_ACE_SUBJ_STANDARD = 0, /* subject is one of key_ace_standard_subject */ + nr__key_ace_subject_type +}; + +enum key_ace_standard_subject { + KEY_ACE_EVERYONE = 0, /* Everyone, including owner and group */ + KEY_ACE_GROUP = 1, /* The key's group */ + KEY_ACE_OWNER = 2, /* The owner of the key */ + KEY_ACE_POSSESSOR = 3, /* Any process that possesses of the key */ + nr__key_ace_standard_subject +}; + +#define KEY_ACE_VIEW 0x00000001 /* Can describe the key */ +#define KEY_ACE_READ 0x00000002 /* Can read the key content */ +#define KEY_ACE_WRITE 0x00000004 /* Can update/modify the key content */ +#define KEY_ACE_SEARCH 0x00000008 /* Can find the key by search */ +#define KEY_ACE_LINK 0x00000010 /* Can make a link to the key */ +#define KEY_ACE_SET_SECURITY 0x00000020 /* Can set owner, group, ACL */ +#define KEY_ACE_INVAL 0x00000040 /* Can invalidate the key */ +#define KEY_ACE_REVOKE 0x00000080 /* Can revoke the key */ +#define KEY_ACE_JOIN 0x00000100 /* Can join keyring */ +#define KEY_ACE_CLEAR 0x00000200 /* Can clear keyring */ +#define KEY_ACE__PERMS 0xffffffff + +/* + * Old-style permissions mask, deprecated in favour of ACL. + */ +#define KEY_POS_VIEW 0x01000000 /* possessor can view a key's attributes */ +#define KEY_POS_READ 0x02000000 /* possessor can read key payload / view keyring */ +#define KEY_POS_WRITE 0x04000000 /* possessor can update key payload / add link to keyring */ +#define KEY_POS_SEARCH 0x08000000 /* possessor can find a key in search / search a keyring */ +#define KEY_POS_LINK 0x10000000 /* possessor can create a link to a key/keyring */ +#define KEY_POS_SETATTR 0x20000000 /* possessor can set key attributes */ +#define KEY_POS_ALL 0x3f000000 + +#define KEY_USR_VIEW 0x00010000 /* user permissions... */ +#define KEY_USR_READ 0x00020000 +#define KEY_USR_WRITE 0x00040000 +#define KEY_USR_SEARCH 0x00080000 +#define KEY_USR_LINK 0x00100000 +#define KEY_USR_SETATTR 0x00200000 +#define KEY_USR_ALL 0x003f0000 + +#define KEY_GRP_VIEW 0x00000100 /* group permissions... */ +#define KEY_GRP_READ 0x00000200 +#define KEY_GRP_WRITE 0x00000400 +#define KEY_GRP_SEARCH 0x00000800 +#define KEY_GRP_LINK 0x00001000 +#define KEY_GRP_SETATTR 0x00002000 +#define KEY_GRP_ALL 0x00003f00 + +#define KEY_OTH_VIEW 0x00000001 /* third party permissions... */ +#define KEY_OTH_READ 0x00000002 +#define KEY_OTH_WRITE 0x00000004 +#define KEY_OTH_SEARCH 0x00000008 +#define KEY_OTH_LINK 0x00000010 +#define KEY_OTH_SETATTR 0x00000020 +#define KEY_OTH_ALL 0x0000003f + /* special process keyring shortcut IDs */ #define KEY_SPEC_THREAD_KEYRING -1 /* - key ID for thread-specific keyring */ #define KEY_SPEC_PROCESS_KEYRING -2 /* - key ID for process-specific keyring */ @@ -69,6 +132,7 @@ #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_GRANT_PERMISSION 32 /* Grant a permit to a key */ /* keyctl structures */ struct keyctl_dh_params { @@ -130,5 +194,6 @@ 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_ACL_ALTERABLE 0x04 /* Keys have internal ACL that can be altered */ #endif /* _LINUX_KEYCTL_H */ diff --git a/lib/digsig.c b/lib/digsig.c index e0627c3e53b2..ab0800f98eaf 100644 --- a/lib/digsig.c +++ b/lib/digsig.c @@ -224,7 +224,7 @@ int digsig_verify(struct key *keyring, const char *sig, int siglen, else key = key_ref_to_ptr(kref); } else { - key = request_key(&key_type_user, name, NULL); + key = request_key(&key_type_user, name, NULL, NULL); } if (IS_ERR(key)) { pr_err("key not found, id: %s\n", name); diff --git a/net/ceph/ceph_common.c b/net/ceph/ceph_common.c index 1c811c74bfc0..38de80d01aae 100644 --- a/net/ceph/ceph_common.c +++ b/net/ceph/ceph_common.c @@ -306,7 +306,7 @@ static int get_secret(struct ceph_crypto_key *dst, const char *name) { int err = 0; struct ceph_crypto_key *ckey; - ukey = request_key(&key_type_ceph, name, NULL); + ukey = request_key(&key_type_ceph, name, NULL, NULL); if (IS_ERR(ukey)) { /* request_key errors don't map nicely to mount(2) errors; don't even try, but still printk */ diff --git a/net/dns_resolver/dns_key.c b/net/dns_resolver/dns_key.c index 3e1a90669006..6b201531b165 100644 --- a/net/dns_resolver/dns_key.c +++ b/net/dns_resolver/dns_key.c @@ -46,6 +46,15 @@ const struct cred *dns_resolver_cache; #define DNS_ERRORNO_OPTION "dnserror" +static struct key_acl dns_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_CLEAR), + } +}; + /* * Preparse instantiation data for a dns_resolver key. * @@ -343,8 +352,7 @@ static int __init init_dns_resolver(void) keyring = keyring_alloc(".dns_resolver", GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ, + &dns_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c index cab4e0df924f..236baf2bfa4c 100644 --- a/net/dns_resolver/dns_query.c +++ b/net/dns_resolver/dns_query.c @@ -47,6 +47,16 @@ #include "internal.h" +static struct key_acl dns_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_INVAL), + } +}; + /** * dns_query - Query the DNS * @net: The network namespace to operate in. @@ -125,7 +135,8 @@ int dns_query(struct net *net, * add_key() to preinstall malicious redirections */ saved_cred = override_creds(dns_resolver_cache); - rkey = request_key_net(&key_type_dns_resolver, desc, net, options); + rkey = request_key_net(&key_type_dns_resolver, desc, net, options, + &dns_key_acl); revert_creds(saved_cred); kfree(desc); if (IS_ERR(rkey)) { @@ -135,8 +146,6 @@ int dns_query(struct net *net, down_read(&rkey->sem); set_bit(KEY_FLAG_ROOT_CAN_INVAL, &rkey->flags); - rkey->perm |= KEY_USR_VIEW; - ret = key_validate(rkey); if (ret < 0) goto put; diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c index 6c3f35fac42d..2032f6a8225e 100644 --- a/net/rxrpc/key.c +++ b/net/rxrpc/key.c @@ -23,6 +23,14 @@ #include <keys/user-type.h> #include "ar-internal.h" +static struct key_acl rxrpc_null_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 1, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_READ), + } +}; + static int rxrpc_vet_description_s(const char *); static int rxrpc_preparse(struct key_preparsed_payload *); static int rxrpc_preparse_s(struct key_preparsed_payload *); @@ -910,7 +918,8 @@ int rxrpc_request_key(struct rxrpc_sock *rx, char __user *optval, int optlen) if (IS_ERR(description)) return PTR_ERR(description); - key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), NULL); + key = request_key_net(&key_type_rxrpc, description, sock_net(&rx->sk), + NULL, NULL); if (IS_ERR(key)) { kfree(description); _leave(" = %ld", PTR_ERR(key)); @@ -941,7 +950,8 @@ int rxrpc_server_keyring(struct rxrpc_sock *rx, char __user *optval, if (IS_ERR(description)) return PTR_ERR(description); - key = request_key_net(&key_type_keyring, description, sock_net(&rx->sk), NULL); + key = request_key_net(&key_type_keyring, description, sock_net(&rx->sk), + NULL, NULL); if (IS_ERR(key)) { kfree(description); _leave(" = %ld", PTR_ERR(key)); @@ -974,7 +984,8 @@ int rxrpc_get_server_data_key(struct rxrpc_connection *conn, _enter(""); key = key_alloc(&key_type_rxrpc, "x", - GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0, + GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, + &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(key)) { _leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key)); @@ -1022,7 +1033,7 @@ struct key *rxrpc_get_null_key(const char *keyname) key = key_alloc(&key_type_rxrpc, keyname, GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, - KEY_POS_SEARCH, KEY_ALLOC_NOT_IN_QUOTA, NULL); + &rxrpc_null_key_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(key)) return key; diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 4831ad745f91..298fe91557f7 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -741,8 +741,7 @@ static void __init load_keys_from_buffer(const u8 *p, unsigned int buflen) key = key_create_or_update(make_key_ref(builtin_regdb_keys, 1), "asymmetric", NULL, p, plen, - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), + &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_BUILT_IN | KEY_ALLOC_BYPASS_RESTRICTION); @@ -768,8 +767,7 @@ static int __init load_builtin_regdb_keys(void) builtin_regdb_keys = keyring_alloc(".builtin_regdb_keys", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ | KEY_USR_SEARCH), + &internal_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(builtin_regdb_keys)) return PTR_ERR(builtin_regdb_keys); diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index 4582bc26770a..ceb10553a6ba 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -47,7 +47,8 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, if (!keyring[id]) { keyring[id] = - request_key(&key_type_keyring, keyring_name[id], NULL); + request_key(&key_type_keyring, keyring_name[id], + NULL, NULL); if (IS_ERR(keyring[id])) { int err = PTR_ERR(keyring[id]); pr_err("no %s keyring: %d\n", keyring_name[id], err); @@ -69,14 +70,14 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, return -EOPNOTSUPP; } -static int __integrity_init_keyring(const unsigned int id, key_perm_t perm, +static int __integrity_init_keyring(const unsigned int id, struct key_acl *acl, struct key_restriction *restriction) { const struct cred *cred = current_cred(); int err = 0; keyring[id] = keyring_alloc(keyring_name[id], KUIDT_INIT(0), - KGIDT_INIT(0), cred, perm, + KGIDT_INIT(0), cred, acl, KEY_ALLOC_NOT_IN_QUOTA, restriction, NULL); if (IS_ERR(keyring[id])) { err = PTR_ERR(keyring[id]); @@ -94,10 +95,7 @@ static int __integrity_init_keyring(const unsigned int id, key_perm_t perm, int __init integrity_init_keyring(const unsigned int id) { struct key_restriction *restriction; - key_perm_t perm; - - perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW - | KEY_USR_READ | KEY_USR_SEARCH; + struct key_acl *acl = &internal_keyring_acl; if (id == INTEGRITY_KEYRING_PLATFORM) { restriction = NULL; @@ -112,14 +110,14 @@ int __init integrity_init_keyring(const unsigned int id) return -ENOMEM; restriction->check = restrict_link_to_ima; - perm |= KEY_USR_WRITE; + acl = &internal_writable_keyring_acl; out: - return __integrity_init_keyring(id, perm, restriction); + return __integrity_init_keyring(id, acl, restriction); } -int __init integrity_add_key(const unsigned int id, const void *data, - off_t size, key_perm_t perm) +static int __init integrity_add_key(const unsigned int id, const void *data, + off_t size, struct key_acl *acl) { key_ref_t key; int rc = 0; @@ -128,7 +126,7 @@ int __init integrity_add_key(const unsigned int id, const void *data, return -EINVAL; key = key_create_or_update(make_key_ref(keyring[id], 1), "asymmetric", - NULL, data, size, perm, + NULL, data, size, acl ?: &internal_key_acl, KEY_ALLOC_NOT_IN_QUOTA); if (IS_ERR(key)) { rc = PTR_ERR(key); @@ -148,7 +146,6 @@ int __init integrity_load_x509(const unsigned int id, const char *path) void *data; loff_t size; int rc; - key_perm_t perm; rc = kernel_read_file_from_path(path, &data, &size, 0, READING_X509_CERTIFICATE); @@ -157,21 +154,19 @@ int __init integrity_load_x509(const unsigned int id, const char *path) return rc; } - perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ; - pr_info("Loading X.509 certificate: %s\n", path); - rc = integrity_add_key(id, (const void *)data, size, perm); + rc = integrity_add_key(id, data, size, NULL); vfree(data); return rc; } int __init integrity_load_cert(const unsigned int id, const char *source, - const void *data, size_t len, key_perm_t perm) + const void *data, size_t len, struct key_acl *acl) { if (!data) return -EINVAL; pr_info("Loading X.509 certificate: %s\n", source); - return integrity_add_key(id, data, len, perm); + return integrity_add_key(id, data, len, acl); } diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c index 55aec161d0e1..a29df775fdd8 100644 --- a/security/integrity/digsig_asymmetric.c +++ b/security/integrity/digsig_asymmetric.c @@ -53,7 +53,7 @@ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) else key = key_ref_to_ptr(kref); } else { - key = request_key(&key_type_asymmetric, name, NULL); + key = request_key(&key_type_asymmetric, name, NULL, NULL); } if (IS_ERR(key)) { diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index d485f6fc908e..466eebd3b4aa 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -356,7 +356,7 @@ int evm_init_key(void) struct encrypted_key_payload *ekp; int rc; - evm_key = request_key(&key_type_encrypted, EVMKEY, NULL); + evm_key = request_key(&key_type_encrypted, EVMKEY, NULL, NULL); if (IS_ERR(evm_key)) return -ENOENT; diff --git a/security/integrity/ima/ima_mok.c b/security/integrity/ima/ima_mok.c index 36cadadbfba4..b52ae1476ec3 100644 --- a/security/integrity/ima/ima_mok.c +++ b/security/integrity/ima/ima_mok.c @@ -16,6 +16,15 @@ #include <keys/system_keyring.h> +static struct key_acl integrity_blacklist_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | KEY_ACE_SEARCH), + } +}; + struct key *ima_blacklist_keyring; /* @@ -35,9 +44,7 @@ __init int ima_mok_init(void) ima_blacklist_keyring = keyring_alloc(".ima_blacklist", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - (KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ | - KEY_USR_WRITE | KEY_USR_SEARCH, + &integrity_blacklist_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, restriction, NULL); diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 65377848fbc5..45f4aef83e29 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -12,6 +12,8 @@ #include <linux/key.h> #include <linux/audit.h> +struct key_acl; + /* iint action cache flags */ #define IMA_MEASURE 0x00000001 #define IMA_MEASURED 0x00000002 @@ -149,7 +151,7 @@ int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen, int __init integrity_init_keyring(const unsigned int id); int __init integrity_load_x509(const unsigned int id, const char *path); int __init integrity_load_cert(const unsigned int id, const char *source, - const void *data, size_t len, key_perm_t perm); + const void *data, size_t len, struct key_acl *acl); #else static inline int integrity_digsig_verify(const unsigned int id, @@ -167,7 +169,7 @@ static inline int integrity_init_keyring(const unsigned int id) static inline int __init integrity_load_cert(const unsigned int id, const char *source, const void *data, size_t len, - key_perm_t perm) + struct key_acl *acl) { return 0; } diff --git a/security/integrity/platform_certs/platform_keyring.c b/security/integrity/platform_certs/platform_keyring.c index bcafd7387729..7646e35f2d91 100644 --- a/security/integrity/platform_certs/platform_keyring.c +++ b/security/integrity/platform_certs/platform_keyring.c @@ -14,6 +14,15 @@ #include <linux/slab.h> #include "../integrity.h" +static struct key_acl platform_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_READ), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + /** * add_to_platform_keyring - Add to platform keyring without validation. * @source: Source of key @@ -26,13 +35,10 @@ void __init add_to_platform_keyring(const char *source, const void *data, size_t len) { - key_perm_t perm; int rc; - perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW; - rc = integrity_load_cert(INTEGRITY_KEYRING_PLATFORM, source, data, len, - perm); + &platform_key_acl); if (rc) pr_info("Error adding keys to platform keyring %s\n", source); } diff --git a/security/keys/compat.c b/security/keys/compat.c index 9bcc404131aa..b0e59546e7bd 100644 --- a/security/keys/compat.c +++ b/security/keys/compat.c @@ -157,6 +157,8 @@ COMPAT_SYSCALL_DEFINE5(keyctl, u32, option, case KEYCTL_MOVE: return keyctl_keyring_move(arg2, arg3, arg4, arg5); + case KEYCTL_GRANT_PERMISSION: + return keyctl_grant_permission(arg2, arg3, arg4, arg5); case KEYCTL_CAPABILITIES: return keyctl_capabilities(compat_ptr(arg2), arg3); diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index 60720f58cbe0..9df560e477c2 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -304,7 +304,7 @@ static struct key *request_user_key(const char *master_desc, const u8 **master_k const struct user_key_payload *upayload; struct key *ukey; - ukey = request_key(&key_type_user, master_desc, NULL); + ukey = request_key(&key_type_user, master_desc, NULL, NULL); if (IS_ERR(ukey)) goto error; diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c index c68528aa49c6..d649f2f29475 100644 --- a/security/keys/encrypted-keys/masterkey_trusted.c +++ b/security/keys/encrypted-keys/masterkey_trusted.c @@ -30,7 +30,7 @@ struct key *request_trusted_key(const char *trusted_desc, struct trusted_key_payload *tpayload; struct key *tkey; - tkey = request_key(&key_type_trusted, trusted_desc, NULL); + tkey = request_key(&key_type_trusted, trusted_desc, NULL, NULL); if (IS_ERR(tkey)) goto error; diff --git a/security/keys/gc.c b/security/keys/gc.c index 671dd730ecfc..48c3e124c272 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -151,6 +151,7 @@ static noinline void key_gc_unused_keys(struct list_head *keys) key_user_put(key->user); key_put_tag(key->domain_tag); + key_put_acl(rcu_access_pointer(key->acl)); kfree(key->description); memzero_explicit(key, sizeof(*key)); @@ -220,7 +221,6 @@ continue_scanning: if (key->type == key_gc_dead_keytype) { gc_state |= KEY_GC_FOUND_DEAD_KEY; set_bit(KEY_FLAG_DEAD, &key->flags); - key->perm = 0; goto skip_dead_key; } else if (key->type == &key_type_keyring && key->restrict_link) { diff --git a/security/keys/internal.h b/security/keys/internal.h index c039373488bd..e0c5bb8b1685 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -84,8 +84,11 @@ 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_acl default_key_acl; +extern struct key_acl joinable_keyring_acl; extern void key_set_index_key(struct keyring_index_key *index_key); + extern struct key_type *key_type_lookup(const char *type); extern void key_type_put(struct key_type *ktype); @@ -156,6 +159,7 @@ extern struct key *request_key_and_link(struct key_type *type, const void *callout_info, size_t callout_len, void *aux, + struct key_acl *acl, struct key *dest_keyring, unsigned long flags); @@ -179,7 +183,10 @@ 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); + u32 desired_perm); +extern unsigned int key_acl_to_perm(const struct key_acl *acl); +extern long key_set_acl(struct key *key, struct key_acl *acl); +extern void key_put_acl(struct key_acl *acl); /* * Check to see whether permission is granted to use a key in the desired way. @@ -226,7 +233,7 @@ 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_setperm_key(key_serial_t, unsigned int); 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); @@ -331,6 +338,11 @@ static inline long keyctl_pkey_e_d_s(int op, extern long keyctl_capabilities(unsigned char __user *_buffer, size_t buflen); +extern long keyctl_grant_permission(key_serial_t keyid, + enum key_ace_subject_type type, + unsigned int subject, + unsigned int perm); + /* * Debugging key validation */ diff --git a/security/keys/key.c b/security/keys/key.c index 764f4c57913e..519211a996e7 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -195,7 +195,7 @@ serial_exists: * @uid: The owner of the new key. * @gid: The group ID for the new key's group permissions. * @cred: The credentials specifying UID namespace. - * @perm: The permissions mask of the new key. + * @acl: The ACL to attach to the new key. * @flags: Flags specifying quota properties. * @restrict_link: Optional link restriction for new keyrings. * @@ -223,7 +223,7 @@ serial_exists: */ struct key *key_alloc(struct key_type *type, const char *desc, kuid_t uid, kgid_t gid, const struct cred *cred, - key_perm_t perm, unsigned long flags, + struct key_acl *acl, unsigned long flags, struct key_restriction *restrict_link) { struct key_user *user = NULL; @@ -246,6 +246,9 @@ struct key *key_alloc(struct key_type *type, const char *desc, desclen = strlen(desc); quotalen = desclen + 1 + type->def_datalen; + if (!acl) + acl = &default_key_acl; + /* get hold of the key tracking for this user */ user = key_user_lookup(uid); if (!user) @@ -292,7 +295,8 @@ struct key *key_alloc(struct key_type *type, const char *desc, key->datalen = type->def_datalen; key->uid = uid; key->gid = gid; - key->perm = perm; + refcount_inc(&acl->usage); + rcu_assign_pointer(key->acl, acl); key->restrict_link = restrict_link; key->last_used_at = ktime_get_real_seconds(); @@ -787,7 +791,7 @@ error: * @description: The searchable description for the key. * @payload: The data to use to instantiate or update the key. * @plen: The length of @payload. - * @perm: The permissions mask for a new key. + * @acl: The ACL to attach if a key is created. * @flags: The quota flags for a new key. * * Search the destination keyring for a key of the same description and if one @@ -810,7 +814,7 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, const char *description, const void *payload, size_t plen, - key_perm_t perm, + struct key_acl *acl, unsigned long flags) { struct keyring_index_key index_key = { @@ -907,22 +911,9 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref, goto found_matching_key; } - /* if the client doesn't provide, decide on the permissions we want */ - if (perm == KEY_PERM_UNDEF) { - perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; - perm |= KEY_USR_VIEW; - - if (index_key.type->read) - perm |= KEY_POS_READ; - - if (index_key.type == &key_type_keyring || - index_key.type->update) - perm |= KEY_POS_WRITE; - } - /* allocate a new key */ key = key_alloc(index_key.type, index_key.description, - cred->fsuid, cred->fsgid, cred, perm, flags, NULL); + cred->fsuid, cred->fsgid, cred, acl, flags, NULL); if (IS_ERR(key)) { key_ref = ERR_CAST(key); goto error_link_end; diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 9b898c969558..c2dd66d556d4 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -37,7 +37,8 @@ static const unsigned char keyrings_capabilities[2] = { KEYCTL_CAPS0_MOVE ), [1] = (KEYCTL_CAPS1_NS_KEYRING_NAME | - KEYCTL_CAPS1_NS_KEY_TAG), + KEYCTL_CAPS1_NS_KEY_TAG | + KEYCTL_CAPS1_ACL_ALTERABLE), }; static int key_get_type_from_user(char *type, @@ -130,8 +131,7 @@ SYSCALL_DEFINE5(add_key, const char __user *, _type, /* create or update the requested key and add it to the target * keyring */ key_ref = key_create_or_update(keyring_ref, type, description, - payload, plen, KEY_PERM_UNDEF, - KEY_ALLOC_IN_QUOTA); + payload, plen, NULL, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key_ref)) { ret = key_ref_to_ptr(key_ref)->serial; key_ref_put(key_ref); @@ -221,7 +221,8 @@ SYSCALL_DEFINE4(request_key, const char __user *, _type, /* do the search */ key = request_key_and_link(ktype, description, NULL, callout_info, - callout_len, NULL, key_ref_to_ptr(dest_ref), + callout_len, NULL, NULL, + key_ref_to_ptr(dest_ref), KEY_ALLOC_IN_QUOTA); if (IS_ERR(key)) { ret = PTR_ERR(key); @@ -383,16 +384,10 @@ long keyctl_revoke_key(key_serial_t id) struct key *key; long ret; - key_ref = lookup_user_key(id, 0, KEY_NEED_WRITE); + key_ref = lookup_user_key(id, 0, KEY_NEED_REVOKE); if (IS_ERR(key_ref)) { ret = PTR_ERR(key_ref); - if (ret != -EACCES) - goto error; - key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR); - if (IS_ERR(key_ref)) { - ret = PTR_ERR(key_ref); - goto error; - } + goto error; } key = key_ref_to_ptr(key_ref); @@ -426,7 +421,7 @@ long keyctl_invalidate_key(key_serial_t id) kenter("%d", id); - key_ref = lookup_user_key(id, 0, KEY_NEED_SEARCH); + key_ref = lookup_user_key(id, 0, KEY_NEED_INVAL); if (IS_ERR(key_ref)) { ret = PTR_ERR(key_ref); @@ -471,7 +466,7 @@ long keyctl_keyring_clear(key_serial_t ringid) struct key *keyring; long ret; - keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_WRITE); + keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_NEED_CLEAR); if (IS_ERR(keyring_ref)) { ret = PTR_ERR(keyring_ref); @@ -646,6 +641,7 @@ long keyctl_describe_key(key_serial_t keyid, size_t buflen) { struct key *key, *instkey; + unsigned int perm; key_ref_t key_ref; char *infobuf; long ret; @@ -675,6 +671,10 @@ okay: key = key_ref_to_ptr(key_ref); desclen = strlen(key->description); + rcu_read_lock(); + perm = key_acl_to_perm(rcu_dereference(key->acl)); + rcu_read_unlock(); + /* calculate how much information we're going to return */ ret = -ENOMEM; infobuf = kasprintf(GFP_KERNEL, @@ -682,7 +682,7 @@ okay: key->type->name, from_kuid_munged(current_user_ns(), key->uid), from_kgid_munged(current_user_ns(), key->gid), - key->perm); + perm); if (!infobuf) goto error2; infolen = strlen(infobuf); @@ -899,7 +899,7 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group) goto error; key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, - KEY_NEED_SETATTR); + KEY_NEED_SETSEC); if (IS_ERR(key_ref)) { ret = PTR_ERR(key_ref); goto error; @@ -994,18 +994,25 @@ quota_overrun: * the key need not be fully instantiated yet. If the caller does not have * sysadmin capability, it may only change the permission on keys that it owns. */ -long keyctl_setperm_key(key_serial_t id, key_perm_t perm) +long keyctl_setperm_key(key_serial_t id, unsigned int perm) { + struct key_acl *acl; struct key *key; key_ref_t key_ref; long ret; + int nr, i, j; - ret = -EINVAL; if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL)) - goto error; + return -EINVAL; + + nr = 0; + if (perm & KEY_POS_ALL) nr++; + if (perm & KEY_USR_ALL) nr++; + if (perm & KEY_GRP_ALL) nr++; + if (perm & KEY_OTH_ALL) nr++; key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, - KEY_NEED_SETATTR); + KEY_NEED_SETSEC); if (IS_ERR(key_ref)) { ret = PTR_ERR(key_ref); goto error; @@ -1013,17 +1020,45 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm) key = key_ref_to_ptr(key_ref); - /* make the changes with the locks held to prevent chown/chmod races */ - ret = -EACCES; - down_write(&key->sem); + ret = -EOPNOTSUPP; + if (test_bit(KEY_FLAG_HAS_ACL, &key->flags)) + goto error_key; - /* if we're not the sysadmin, we can only change a key that we own */ - if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) { - key->perm = perm; - ret = 0; + ret = -ENOMEM; + acl = kzalloc(struct_size(acl, aces, nr), GFP_KERNEL); + if (!acl) + goto error_key; + + refcount_set(&acl->usage, 1); + acl->nr_ace = nr; + j = 0; + for (i = 0; i < 4; i++) { + struct key_ace *ace = &acl->aces[j]; + unsigned int subset = (perm >> (i * 8)) & KEY_OTH_ALL; + + if (!subset) + continue; + ace->type = KEY_ACE_SUBJ_STANDARD; + ace->subject_id = KEY_ACE_EVERYONE + i; + ace->perm = subset; + if (subset & (KEY_OTH_WRITE | KEY_OTH_SETATTR)) + ace->perm |= KEY_ACE_REVOKE; + if (subset & KEY_OTH_SEARCH) + ace->perm |= KEY_ACE_INVAL; + if (key->type == &key_type_keyring) { + if (subset & KEY_OTH_SEARCH) + ace->perm |= KEY_ACE_JOIN; + if (subset & KEY_OTH_WRITE) + ace->perm |= KEY_ACE_CLEAR; + } + j++; } + /* make the changes with the locks held to prevent chown/chmod races */ + down_write(&key->sem); + ret = key_set_acl(key, acl); up_write(&key->sem); +error_key: key_put(key); error: return ret; @@ -1388,7 +1423,7 @@ long keyctl_set_timeout(key_serial_t id, unsigned timeout) long ret; key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL, - KEY_NEED_SETATTR); + KEY_NEED_SETSEC); if (IS_ERR(key_ref)) { /* setting the timeout on a key under construction is permitted * if we have the authorisation token handy */ @@ -1539,7 +1574,7 @@ long keyctl_get_security(key_serial_t keyid, * Attempt to install the calling process's session keyring on the process's * parent process. * - * The keyring must exist and must grant the caller LINK permission, and the + * The keyring must exist and must grant the caller JOIN permission, and the * parent process must be single-threaded and must have the same effective * ownership as this process and mustn't be SUID/SGID. * @@ -1556,7 +1591,7 @@ long keyctl_session_to_parent(void) struct cred *cred; int ret; - keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_NEED_LINK); + keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_NEED_JOIN); if (IS_ERR(keyring_r)) return PTR_ERR(keyring_r); @@ -1658,7 +1693,7 @@ long keyctl_restrict_keyring(key_serial_t id, const char __user *_type, char *restriction = NULL; long ret; - key_ref = lookup_user_key(id, 0, KEY_NEED_SETATTR); + key_ref = lookup_user_key(id, 0, KEY_NEED_SETSEC); if (IS_ERR(key_ref)) return PTR_ERR(key_ref); @@ -1764,7 +1799,7 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, case KEYCTL_SETPERM: return keyctl_setperm_key((key_serial_t) arg2, - (key_perm_t) arg3); + (unsigned int)arg3); case KEYCTL_INSTANTIATE: return keyctl_instantiate_key((key_serial_t) arg2, @@ -1853,6 +1888,11 @@ SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3, (key_serial_t)arg3, (key_serial_t)arg4, (unsigned int)arg5); + case KEYCTL_GRANT_PERMISSION: + return keyctl_grant_permission((key_serial_t)arg2, + (enum key_ace_subject_type)arg3, + (unsigned int)arg4, + (unsigned int)arg5); case KEYCTL_CAPABILITIES: return keyctl_capabilities((unsigned char __user *)arg2, (size_t)arg3); diff --git a/security/keys/keyring.c b/security/keys/keyring.c index febf36c6ddc5..3b5458f23a95 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -515,11 +515,19 @@ static long keyring_read(const struct key *keyring, return ret; } -/* - * Allocate a keyring and link into the destination keyring. +/** + * keyring_alloc - Allocate a keyring and link into the destination + * @description: The key description to allow the key to be searched out. + * @uid: The owner of the new key. + * @gid: The group ID for the new key's group permissions. + * @cred: The credentials specifying UID namespace. + * @acl: The ACL to attach to the new key. + * @flags: Flags specifying quota properties. + * @restrict_link: Optional link restriction for new keyrings. + * @dest: Destination keyring. */ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, - const struct cred *cred, key_perm_t perm, + const struct cred *cred, struct key_acl *acl, unsigned long flags, struct key_restriction *restrict_link, struct key *dest) @@ -528,7 +536,7 @@ struct key *keyring_alloc(const char *description, kuid_t uid, kgid_t gid, int ret; keyring = key_alloc(&key_type_keyring, description, - uid, gid, cred, perm, flags, restrict_link); + uid, gid, cred, acl, flags, restrict_link); if (!IS_ERR(keyring)) { ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); if (ret < 0) { @@ -1132,10 +1140,11 @@ found: /* * Find a keyring with the specified name. * - * Only keyrings that have nonzero refcount, are not revoked, and are owned by a - * user in the current user namespace are considered. If @uid_keyring is %true, - * the keyring additionally must have been allocated as a user or user session - * keyring; otherwise, it must grant Search permission directly to the caller. + * Only keyrings that have nonzero refcount, are not revoked, and are owned by + * a user in the current user namespace are considered. If @uid_keyring is + * %true, the keyring additionally must have been allocated as a user or user + * session keyring; otherwise, it must grant JOIN permission directly to the + * caller (ie. not through possession). * * Returns a pointer to the keyring with the keyring's refcount having being * incremented on success. -ENOKEY is returned if a key could not be found. @@ -1169,7 +1178,7 @@ struct key *find_keyring_by_name(const char *name, bool uid_keyring) continue; } else { if (key_permission(make_key_ref(keyring, 0), - KEY_NEED_SEARCH) < 0) + KEY_NEED_JOIN) < 0) continue; } diff --git a/security/keys/permission.c b/security/keys/permission.c index 085f907b64ac..fd8a5dc6910a 100644 --- a/security/keys/permission.c +++ b/security/keys/permission.c @@ -7,13 +7,67 @@ #include <linux/export.h> #include <linux/security.h> +#include <linux/user_namespace.h> +#include <linux/uaccess.h> #include "internal.h" +struct key_acl default_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE__PERMS & ~KEY_ACE_JOIN), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; +EXPORT_SYMBOL(default_key_acl); + +struct key_acl joinable_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE__PERMS & ~KEY_ACE_JOIN), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_LINK | KEY_ACE_JOIN), + } +}; +EXPORT_SYMBOL(joinable_keyring_acl); + +struct key_acl internal_key_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_SEARCH), + } +}; +EXPORT_SYMBOL(internal_key_acl); + +struct key_acl internal_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_SEARCH), + } +}; +EXPORT_SYMBOL(internal_keyring_acl); + +struct key_acl internal_writable_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | KEY_ACE_SEARCH), + } +}; +EXPORT_SYMBOL(internal_writable_keyring_acl); + /** * key_task_permission - Check a key can be used * @key_ref: The key to check. * @cred: The credentials to use. - * @perm: The permissions to check for. + * @desired_perm: The permission to check for. * * Check to see whether permission is granted to use a key in the desired way, * but permit the security modules to override. @@ -24,53 +78,73 @@ * permissions bits or the LSM check. */ int key_task_permission(const key_ref_t key_ref, const struct cred *cred, - unsigned perm) + unsigned int desired_perm) { - struct key *key; - key_perm_t kperm; - int ret; + const struct key_acl *acl; + const struct key *key; + unsigned int allow = 0; + int i; + + BUILD_BUG_ON(KEY_NEED_VIEW != KEY_ACE_VIEW || + KEY_NEED_READ != KEY_ACE_READ || + KEY_NEED_WRITE != KEY_ACE_WRITE || + KEY_NEED_SEARCH != KEY_ACE_SEARCH || + KEY_NEED_LINK != KEY_ACE_LINK || + KEY_NEED_SETSEC != KEY_ACE_SET_SECURITY || + KEY_NEED_INVAL != KEY_ACE_INVAL || + KEY_NEED_REVOKE != KEY_ACE_REVOKE || + KEY_NEED_JOIN != KEY_ACE_JOIN || + KEY_NEED_CLEAR != KEY_ACE_CLEAR); key = key_ref_to_ptr(key_ref); - /* use the second 8-bits of permissions for keys the caller owns */ - if (uid_eq(key->uid, cred->fsuid)) { - kperm = key->perm >> 16; - goto use_these_perms; - } + rcu_read_lock(); - /* use the third 8-bits of permissions for keys the caller has a group - * membership in common with */ - if (gid_valid(key->gid) && key->perm & KEY_GRP_ALL) { - if (gid_eq(key->gid, cred->fsgid)) { - kperm = key->perm >> 8; - goto use_these_perms; - } + acl = rcu_dereference(key->acl); + if (!acl || acl->nr_ace == 0) + goto no_access_rcu; - ret = groups_search(cred->group_info, key->gid); - if (ret) { - kperm = key->perm >> 8; - goto use_these_perms; + for (i = 0; i < acl->nr_ace; i++) { + const struct key_ace *ace = &acl->aces[i]; + + switch (ace->type) { + case KEY_ACE_SUBJ_STANDARD: + switch (ace->subject_id) { + case KEY_ACE_POSSESSOR: + if (is_key_possessed(key_ref)) + allow |= ace->perm; + break; + case KEY_ACE_OWNER: + if (uid_eq(key->uid, cred->fsuid)) + allow |= ace->perm; + break; + case KEY_ACE_GROUP: + if (gid_valid(key->gid)) { + if (gid_eq(key->gid, cred->fsgid)) + allow |= ace->perm; + else if (groups_search(cred->group_info, key->gid)) + allow |= ace->perm; + } + break; + case KEY_ACE_EVERYONE: + allow |= ace->perm; + break; + } + break; } } - /* otherwise use the least-significant 8-bits */ - kperm = key->perm; - -use_these_perms: + rcu_read_unlock(); - /* use the top 8-bits of permissions for keys the caller possesses - * - possessor permissions are additive with other permissions - */ - if (is_key_possessed(key_ref)) - kperm |= key->perm >> 24; + if (!(allow & desired_perm)) + goto no_access; - kperm = kperm & perm & KEY_NEED_ALL; + return security_key_permission(key_ref, cred, desired_perm); - if (kperm != perm) - return -EACCES; - - /* let LSM be the final arbiter */ - return security_key_permission(key_ref, cred, perm); +no_access_rcu: + rcu_read_unlock(); +no_access: + return -EACCES; } EXPORT_SYMBOL(key_task_permission); @@ -104,3 +178,218 @@ int key_validate(const struct key *key) return 0; } EXPORT_SYMBOL(key_validate); + +/* + * Roughly render an ACL to an old-style permissions mask. We cannot + * accurately render what the ACL, particularly if it has ACEs that represent + * subjects outside of { poss, user, group, other }. + */ +unsigned int key_acl_to_perm(const struct key_acl *acl) +{ + unsigned int perm = 0, tperm; + int i; + + BUILD_BUG_ON(KEY_OTH_VIEW != KEY_ACE_VIEW || + KEY_OTH_READ != KEY_ACE_READ || + KEY_OTH_WRITE != KEY_ACE_WRITE || + KEY_OTH_SEARCH != KEY_ACE_SEARCH || + KEY_OTH_LINK != KEY_ACE_LINK || + KEY_OTH_SETATTR != KEY_ACE_SET_SECURITY); + + if (!acl || acl->nr_ace == 0) + return 0; + + for (i = 0; i < acl->nr_ace; i++) { + const struct key_ace *ace = &acl->aces[i]; + + switch (ace->type) { + case KEY_ACE_SUBJ_STANDARD: + tperm = ace->perm & KEY_OTH_ALL; + + /* Invalidation and joining were allowed by SEARCH */ + if (ace->perm & (KEY_ACE_INVAL | KEY_ACE_JOIN)) + tperm |= KEY_OTH_SEARCH; + + /* Revocation was allowed by either SETATTR or WRITE */ + if ((ace->perm & KEY_ACE_REVOKE) && !(tperm & KEY_OTH_SETATTR)) + tperm |= KEY_OTH_WRITE; + + /* Clearing was allowed by WRITE */ + if (ace->perm & KEY_ACE_CLEAR) + tperm |= KEY_OTH_WRITE; + + switch (ace->subject_id) { + case KEY_ACE_POSSESSOR: + perm |= tperm << 24; + break; + case KEY_ACE_OWNER: + perm |= tperm << 16; + break; + case KEY_ACE_GROUP: + perm |= tperm << 8; + break; + case KEY_ACE_EVERYONE: + perm |= tperm << 0; + break; + } + } + } + + return perm; +} + +/* + * Destroy a key's ACL. + */ +void key_put_acl(struct key_acl *acl) +{ + if (acl && refcount_dec_and_test(&acl->usage)) + kfree_rcu(acl, rcu); +} + +/* + * Try to set the ACL. This either attaches or discards the proposed ACL. + */ +long key_set_acl(struct key *key, struct key_acl *acl) +{ + int i; + + /* If we're not the sysadmin, we can only change a key that we own. */ + if (!capable(CAP_SYS_ADMIN) && !uid_eq(key->uid, current_fsuid())) { + key_put_acl(acl); + return -EACCES; + } + + for (i = 0; i < acl->nr_ace; i++) { + const struct key_ace *ace = &acl->aces[i]; + if (ace->type == KEY_ACE_SUBJ_STANDARD && + ace->subject_id == KEY_ACE_POSSESSOR) { + if (ace->perm & KEY_ACE_VIEW) + acl->possessor_viewable = true; + break; + } + } + + rcu_swap_protected(key->acl, acl, lockdep_is_held(&key->sem)); + key_put_acl(acl); + return 0; +} + +/* + * Allocate a new ACL with an extra ACE slot. + */ +static struct key_acl *key_alloc_acl(const struct key_acl *old_acl, int nr, int skip) +{ + struct key_acl *acl; + int nr_ace, i, j = 0; + + nr_ace = old_acl->nr_ace + nr; + if (nr_ace > 16) + return ERR_PTR(-EINVAL); + + acl = kzalloc(struct_size(acl, aces, nr_ace), GFP_KERNEL); + if (!acl) + return ERR_PTR(-ENOMEM); + + refcount_set(&acl->usage, 1); + acl->nr_ace = nr_ace; + for (i = 0; i < old_acl->nr_ace; i++) { + if (i == skip) + continue; + acl->aces[j] = old_acl->aces[i]; + j++; + } + return acl; +} + +/* + * Generate the revised ACL. + */ +static long key_change_acl(struct key *key, struct key_ace *new_ace) +{ + struct key_acl *acl, *old; + int i; + + old = rcu_dereference_protected(key->acl, lockdep_is_held(&key->sem)); + + for (i = 0; i < old->nr_ace; i++) + if (old->aces[i].type == new_ace->type && + old->aces[i].subject_id == new_ace->subject_id) + goto found_match; + + if (new_ace->perm == 0) + return 0; /* No permissions to remove. Add deny record? */ + + acl = key_alloc_acl(old, 1, -1); + if (IS_ERR(acl)) + return PTR_ERR(acl); + acl->aces[i] = *new_ace; + goto change; + +found_match: + if (new_ace->perm == 0) + goto delete_ace; + if (new_ace->perm == old->aces[i].perm) + return 0; + acl = key_alloc_acl(old, 0, -1); + if (IS_ERR(acl)) + return PTR_ERR(acl); + acl->aces[i].perm = new_ace->perm; + goto change; + +delete_ace: + acl = key_alloc_acl(old, -1, i); + if (IS_ERR(acl)) + return PTR_ERR(acl); + goto change; + +change: + return key_set_acl(key, acl); +} + +/* + * Add, alter or remove (if perm == 0) an ACE in a key's ACL. + */ +long keyctl_grant_permission(key_serial_t keyid, + enum key_ace_subject_type type, + unsigned int subject, + unsigned int perm) +{ + struct key_ace new_ace; + struct key *key; + key_ref_t key_ref; + long ret; + + new_ace.type = type; + new_ace.perm = perm; + + switch (type) { + case KEY_ACE_SUBJ_STANDARD: + if (subject >= nr__key_ace_standard_subject) + return -ENOENT; + new_ace.subject_id = subject; + break; + + default: + return -ENOENT; + } + + key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_NEED_SETSEC); + if (IS_ERR(key_ref)) { + ret = PTR_ERR(key_ref); + goto error; + } + + key = key_ref_to_ptr(key_ref); + + down_write(&key->sem); + + /* If we're not the sysadmin, we can only change a key that we own */ + ret = -EACCES; + if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) + ret = key_change_acl(key, &new_ace); + up_write(&key->sem); + key_put(key); +error: + return ret; +} diff --git a/security/keys/persistent.c b/security/keys/persistent.c index 97af230aa4b2..8171c90d4c9a 100644 --- a/security/keys/persistent.c +++ b/security/keys/persistent.c @@ -12,6 +12,27 @@ unsigned persistent_keyring_expiry = 3 * 24 * 3600; /* Expire after 3 days of non-use */ +static struct key_acl persistent_register_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + +static struct key_acl persistent_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | + KEY_ACE_SEARCH | KEY_ACE_LINK | + KEY_ACE_CLEAR | KEY_ACE_INVAL), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + /* * Create the persistent keyring register for the current user namespace. * @@ -22,8 +43,7 @@ static int key_create_persistent_register(struct user_namespace *ns) struct key *reg = keyring_alloc(".persistent_register", KUIDT_INIT(0), KGIDT_INIT(0), current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), + &persistent_register_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL); if (IS_ERR(reg)) return PTR_ERR(reg); @@ -56,8 +76,7 @@ static key_ref_t key_create_persistent(struct user_namespace *ns, kuid_t uid, persistent = keyring_alloc(index_key->description, uid, INVALID_GID, current_cred(), - ((KEY_POS_ALL & ~KEY_POS_SETATTR) | - KEY_USR_VIEW | KEY_USR_READ), + &persistent_keyring_acl, KEY_ALLOC_NOT_IN_QUOTA, NULL, ns->persistent_keyring_register); if (IS_ERR(persistent)) diff --git a/security/keys/proc.c b/security/keys/proc.c index 415f3f1c2da0..b394ad1e874b 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -110,11 +110,13 @@ static struct key *find_ge_key(struct seq_file *p, key_serial_t id) } static void *proc_keys_start(struct seq_file *p, loff_t *_pos) + __acquires(rcu) __acquires(key_serial_lock) { key_serial_t pos = *_pos; struct key *key; + rcu_read_lock(); spin_lock(&key_serial_lock); if (*_pos > INT_MAX) @@ -144,12 +146,15 @@ static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos) static void proc_keys_stop(struct seq_file *p, void *v) __releases(key_serial_lock) + __releases(rcu) { spin_unlock(&key_serial_lock); + rcu_read_unlock(); } static int proc_keys_show(struct seq_file *m, void *v) { + const struct key_acl *acl; struct rb_node *_p = v; struct key *key = rb_entry(_p, struct key, serial_node); unsigned long flags; @@ -157,6 +162,7 @@ static int proc_keys_show(struct seq_file *m, void *v) time64_t now, expiry; char xbuf[16]; short state; + bool check_pos; u64 timo; int rc; @@ -170,15 +176,15 @@ static int proc_keys_show(struct seq_file *m, void *v) KEYRING_SEARCH_RECURSE), }; - key_ref = make_key_ref(key, 0); + acl = rcu_dereference(key->acl); + check_pos = acl->possessor_viewable; /* determine if the key is possessed by this process (a test we can * skip if the key does not indicate the possessor can view it */ - if (key->perm & KEY_POS_VIEW) { - rcu_read_lock(); + key_ref = make_key_ref(key, 0); + if (check_pos) { skey_ref = search_cred_keyrings_rcu(&ctx); - rcu_read_unlock(); if (!IS_ERR(skey_ref)) { key_ref_put(skey_ref); key_ref = make_key_ref(key, 1); @@ -188,12 +194,10 @@ static int proc_keys_show(struct seq_file *m, void *v) /* check whether the current task is allowed to view the key */ rc = key_task_permission(key_ref, ctx.cred, KEY_NEED_VIEW); if (rc < 0) - return 0; + goto out; now = ktime_get_real_seconds(); - rcu_read_lock(); - /* come up with a suitable timeout value */ expiry = READ_ONCE(key->expiry); if (expiry == 0) { @@ -232,7 +236,7 @@ static int proc_keys_show(struct seq_file *m, void *v) showflag(flags, 'i', KEY_FLAG_INVALIDATED), refcount_read(&key->usage), xbuf, - key->perm, + key_acl_to_perm(acl), from_kuid_munged(seq_user_ns(m), key->uid), from_kgid_munged(seq_user_ns(m), key->gid), key->type->name); @@ -243,7 +247,7 @@ static int proc_keys_show(struct seq_file *m, void *v) key->type->describe(key, m); seq_putc(m, '\n'); - rcu_read_unlock(); +out: return 0; } diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 09541de31f2f..aa3bfcadbc66 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -32,6 +32,47 @@ struct key_user root_key_user = { .uid = GLOBAL_ROOT_UID, }; +static struct key_acl user_reg_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .possessor_viewable = true, + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_WRITE | KEY_ACE_SEARCH), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + +static struct key_acl user_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .possessor_viewable = true, + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | + KEY_ACE_SEARCH | KEY_ACE_LINK), + KEY_OWNER_ACE(KEY_ACE__PERMS & ~(KEY_ACE_JOIN | KEY_ACE_SET_SECURITY)), + } +}; + +static struct key_acl session_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .possessor_viewable = true, + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE__PERMS & ~KEY_ACE_JOIN), + KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ), + } +}; + +static struct key_acl thread_and_process_keyring_acl = { + .usage = REFCOUNT_INIT(1), + .possessor_viewable = true, + .nr_ace = 2, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE__PERMS & ~(KEY_ACE_JOIN | KEY_ACE_SET_SECURITY)), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + /* * Get or create a user register keyring. */ @@ -51,11 +92,8 @@ static struct key *get_user_register(struct user_namespace *user_ns) if (!reg_keyring) { reg_keyring = keyring_alloc(".user_reg", user_ns->owner, INVALID_GID, - &init_cred, - KEY_POS_WRITE | KEY_POS_SEARCH | - KEY_USR_VIEW | KEY_USR_READ, - 0, - NULL, NULL); + &init_cred, &user_reg_keyring_acl, + 0, NULL, NULL); if (!IS_ERR(reg_keyring)) smp_store_release(&user_ns->user_keyring_register, reg_keyring); @@ -77,14 +115,11 @@ int look_up_user_keyrings(struct key **_user_keyring, const struct cred *cred = current_cred(); struct user_namespace *user_ns = current_user_ns(); struct key *reg_keyring, *uid_keyring, *session_keyring; - key_perm_t user_keyring_perm; key_ref_t uid_keyring_r, session_keyring_r; uid_t uid = from_kuid(user_ns, cred->user->uid); char buf[20]; int ret; - user_keyring_perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL; - kenter("%u", uid); reg_keyring = get_user_register(user_ns); @@ -104,7 +139,7 @@ int look_up_user_keyrings(struct key **_user_keyring, kdebug("_uid %p", uid_keyring_r); if (uid_keyring_r == ERR_PTR(-EAGAIN)) { uid_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID, - cred, user_keyring_perm, + cred, &user_keyring_acl, KEY_ALLOC_UID_KEYRING | KEY_ALLOC_IN_QUOTA, NULL, reg_keyring); @@ -126,7 +161,7 @@ int look_up_user_keyrings(struct key **_user_keyring, kdebug("_uid_ses %p", session_keyring_r); if (session_keyring_r == ERR_PTR(-EAGAIN)) { session_keyring = keyring_alloc(buf, cred->user->uid, INVALID_GID, - cred, user_keyring_perm, + cred, &user_keyring_acl, KEY_ALLOC_UID_KEYRING | KEY_ALLOC_IN_QUOTA, NULL, NULL); @@ -226,7 +261,7 @@ int install_thread_keyring_to_cred(struct cred *new) return 0; keyring = keyring_alloc("_tid", new->uid, new->gid, new, - KEY_POS_ALL | KEY_USR_VIEW, + &thread_and_process_keyring_acl, KEY_ALLOC_QUOTA_OVERRUN, NULL, NULL); if (IS_ERR(keyring)) @@ -273,7 +308,7 @@ int install_process_keyring_to_cred(struct cred *new) return 0; keyring = keyring_alloc("_pid", new->uid, new->gid, new, - KEY_POS_ALL | KEY_USR_VIEW, + &thread_and_process_keyring_acl, KEY_ALLOC_QUOTA_OVERRUN, NULL, NULL); if (IS_ERR(keyring)) @@ -328,8 +363,7 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring) flags = KEY_ALLOC_IN_QUOTA; keyring = keyring_alloc("_ses", cred->uid, cred->gid, cred, - KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, - flags, NULL, NULL); + &session_keyring_acl, flags, NULL, NULL); if (IS_ERR(keyring)) return PTR_ERR(keyring); } else { @@ -609,7 +643,7 @@ bool lookup_user_key_possessed(const struct key *key, * returned key reference. */ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags, - key_perm_t perm) + unsigned int desired_perm) { struct keyring_search_context ctx = { .match_data.cmp = lookup_user_key_possessed, @@ -784,12 +818,12 @@ try_again: case -ERESTARTSYS: goto invalid_key; default: - if (perm) + if (desired_perm) goto invalid_key; case 0: break; } - } else if (perm) { + } else if (desired_perm) { ret = key_validate(key); if (ret < 0) goto invalid_key; @@ -801,9 +835,11 @@ try_again: goto invalid_key; /* check the permissions */ - ret = key_task_permission(key_ref, ctx.cred, perm); - if (ret < 0) - goto invalid_key; + if (desired_perm) { + ret = key_task_permission(key_ref, ctx.cred, desired_perm); + if (ret < 0) + goto invalid_key; + } key->last_used_at = ktime_get_real_seconds(); @@ -868,13 +904,13 @@ long join_session_keyring(const char *name) if (PTR_ERR(keyring) == -ENOKEY) { /* not found - try and create a new one */ keyring = keyring_alloc( - name, old->uid, old->gid, old, - KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ | KEY_USR_LINK, + name, old->uid, old->gid, old, &joinable_keyring_acl, KEY_ALLOC_IN_QUOTA, NULL, NULL); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error2; } + goto no_perm_test; } else if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); goto error2; @@ -883,6 +919,12 @@ long join_session_keyring(const char *name) goto error3; } + ret = key_task_permission(make_key_ref(keyring, false), old, + KEY_NEED_JOIN); + if (ret < 0) + goto error3; + +no_perm_test: /* we've got a keyring - now to install it */ ret = install_session_keyring_to_cred(new, keyring); if (ret < 0) diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 7325f382dbf4..46c5187ce03f 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -135,8 +135,7 @@ static int call_sbin_request_key(struct key *authkey, void *aux) cred = get_current_cred(); keyring = keyring_alloc(desc, cred->fsuid, cred->fsgid, cred, - KEY_POS_ALL | KEY_USR_VIEW | KEY_USR_READ, - KEY_ALLOC_QUOTA_OVERRUN, NULL, NULL); + NULL, KEY_ALLOC_QUOTA_OVERRUN, NULL, NULL); put_cred(cred); if (IS_ERR(keyring)) { ret = PTR_ERR(keyring); @@ -367,11 +366,11 @@ static int construct_alloc_key(struct keyring_search_context *ctx, struct key *dest_keyring, unsigned long flags, struct key_user *user, + struct key_acl *acl, struct key **_key) { struct assoc_array_edit *edit = NULL; struct key *key; - key_perm_t perm; key_ref_t key_ref; int ret; @@ -381,17 +380,9 @@ static int construct_alloc_key(struct keyring_search_context *ctx, *_key = NULL; mutex_lock(&user->cons_lock); - perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR; - perm |= KEY_USR_VIEW; - if (ctx->index_key.type->read) - perm |= KEY_POS_READ; - if (ctx->index_key.type == &key_type_keyring || - ctx->index_key.type->update) - perm |= KEY_POS_WRITE; - key = key_alloc(ctx->index_key.type, ctx->index_key.description, ctx->cred->fsuid, ctx->cred->fsgid, ctx->cred, - perm, flags, NULL); + acl, flags, NULL); if (IS_ERR(key)) goto alloc_failed; @@ -474,6 +465,7 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, const char *callout_info, size_t callout_len, void *aux, + struct key_acl *acl, struct key *dest_keyring, unsigned long flags) { @@ -496,7 +488,7 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, goto error_put_dest_keyring; } - ret = construct_alloc_key(ctx, dest_keyring, flags, user, &key); + ret = construct_alloc_key(ctx, dest_keyring, flags, user, acl, &key); key_user_put(user); if (ret == 0) { @@ -534,6 +526,7 @@ error: * @callout_info: The data to pass to the instantiation upcall (or NULL). * @callout_len: The length of callout_info. * @aux: Auxiliary data for the upcall. + * @acl: The ACL to attach if a new key is created. * @dest_keyring: Where to cache the key. * @flags: Flags to key_alloc(). * @@ -561,6 +554,7 @@ struct key *request_key_and_link(struct key_type *type, const void *callout_info, size_t callout_len, void *aux, + struct key_acl *acl, struct key *dest_keyring, unsigned long flags) { @@ -635,7 +629,7 @@ struct key *request_key_and_link(struct key_type *type, goto error_free; key = construct_key_and_link(&ctx, callout_info, callout_len, - aux, dest_keyring, flags); + aux, acl, dest_keyring, flags); } error_free: @@ -678,6 +672,7 @@ EXPORT_SYMBOL(wait_for_key_construction); * @description: The searchable description of the key. * @domain_tag: The domain in which the key operates. * @callout_info: The data to pass to the instantiation upcall (or NULL). + * @acl: The ACL to attach if a new key is created. * * As for request_key_and_link() except that it does not add the returned key * to a keyring if found, new keys are always allocated in the user's quota, @@ -690,7 +685,8 @@ EXPORT_SYMBOL(wait_for_key_construction); struct key *request_key_tag(struct key_type *type, const char *description, struct key_tag *domain_tag, - const char *callout_info) + const char *callout_info, + struct key_acl *acl) { struct key *key; size_t callout_len = 0; @@ -700,7 +696,7 @@ struct key *request_key_tag(struct key_type *type, callout_len = strlen(callout_info); key = request_key_and_link(type, description, domain_tag, callout_info, callout_len, - NULL, NULL, KEY_ALLOC_IN_QUOTA); + NULL, acl, NULL, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key)) { ret = wait_for_key_construction(key, false); if (ret < 0) { @@ -720,6 +716,7 @@ EXPORT_SYMBOL(request_key_tag); * @callout_info: The data to pass to the instantiation upcall (or NULL). * @callout_len: The length of callout_info. * @aux: Auxiliary data for the upcall. + * @acl: The ACL to attach if a new key is created. * * As for request_key_and_link() except that it does not add the returned key * to a keyring if found and new keys are always allocated in the user's quota. @@ -732,14 +729,15 @@ struct key *request_key_with_auxdata(struct key_type *type, struct key_tag *domain_tag, const void *callout_info, size_t callout_len, - void *aux) + void *aux, + struct key_acl *acl) { struct key *key; int ret; key = request_key_and_link(type, description, domain_tag, callout_info, callout_len, - aux, NULL, KEY_ALLOC_IN_QUOTA); + aux, acl, NULL, KEY_ALLOC_IN_QUOTA); if (!IS_ERR(key)) { ret = wait_for_key_construction(key, false); if (ret < 0) { diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index e73ec040e250..27e437d94b81 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -24,6 +24,17 @@ static void request_key_auth_revoke(struct key *); static void request_key_auth_destroy(struct key *); static long request_key_auth_read(const struct key *, char __user *, size_t); +static struct key_acl request_key_auth_acl = { + .usage = REFCOUNT_INIT(1), + .nr_ace = 2, + .possessor_viewable = true, + .aces = { + KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_SEARCH | + KEY_ACE_LINK), + KEY_OWNER_ACE(KEY_ACE_VIEW), + } +}; + /* * The request-key authorisation key type definition. */ @@ -210,8 +221,8 @@ struct key *request_key_auth_new(struct key *target, const char *op, authkey = key_alloc(&key_type_request_key_auth, desc, cred->fsuid, cred->fsgid, cred, - KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH | KEY_POS_LINK | - KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA, NULL); + &request_key_auth_acl, + KEY_ALLOC_NOT_IN_QUOTA, NULL); if (IS_ERR(authkey)) { ret = PTR_ERR(authkey); goto error_free_rka; diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3ec7ac70c313..4ed83d869084 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -6502,6 +6502,7 @@ static int selinux_key_permission(key_ref_t key_ref, { struct key *key; struct key_security_struct *ksec; + unsigned oldstyle_perm; u32 sid; /* if no specific permissions are requested, we skip the @@ -6510,13 +6511,26 @@ static int selinux_key_permission(key_ref_t key_ref, if (perm == 0) return 0; + oldstyle_perm = perm & (KEY_NEED_VIEW | KEY_NEED_READ | KEY_NEED_WRITE | + KEY_NEED_SEARCH | KEY_NEED_LINK); + if (perm & KEY_NEED_SETSEC) + oldstyle_perm |= OLD_KEY_NEED_SETATTR; + if (perm & KEY_NEED_INVAL) + oldstyle_perm |= KEY_NEED_SEARCH; + if (perm & KEY_NEED_REVOKE && !(perm & OLD_KEY_NEED_SETATTR)) + oldstyle_perm |= KEY_NEED_WRITE; + if (perm & KEY_NEED_JOIN) + oldstyle_perm |= KEY_NEED_SEARCH; + if (perm & KEY_NEED_CLEAR) + oldstyle_perm |= KEY_NEED_WRITE; + sid = cred_sid(cred); key = key_ref_to_ptr(key_ref); ksec = key->security; return avc_has_perm(&selinux_state, - sid, ksec->sid, SECCLASS_KEY, perm, NULL); + sid, ksec->sid, SECCLASS_KEY, oldstyle_perm, NULL); } static int selinux_key_getsecurity(struct key *key, char **_buffer) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 4c5e5a438f8b..50c536cad85b 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -4284,7 +4284,8 @@ static int smack_key_permission(key_ref_t key_ref, #endif if (perm & (KEY_NEED_READ | KEY_NEED_SEARCH | KEY_NEED_VIEW)) request |= MAY_READ; - if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR)) + if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETSEC | + KEY_NEED_INVAL | KEY_NEED_REVOKE | KEY_NEED_CLEAR)) request |= MAY_WRITE; rc = smk_access(tkp, keyp->security, request, &ad); rc = smk_bu_note("key access", tkp, keyp->security, request, rc); 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