From d7cce01504a0ccb95b5007d846560cfccbc1947f Mon Sep 17 00:00:00 2001 From: Huw Davies Date: Mon, 27 Jun 2016 15:02:49 -0400 Subject: [PATCH] netlabel: Add support for removing a CALIPSO DOI. Remove a specified DOI through the NLBL_CALIPSO_C_REMOVE command. It requires the attribute: NLBL_CALIPSO_A_DOI. Signed-off-by: Huw Davies Signed-off-by: Paul Moore --- include/net/netlabel.h | 1 + net/ipv6/calipso.c | 48 +++++++++++++++++ net/netlabel/netlabel_calipso.c | 92 +++++++++++++++++++++++++++++++++ net/netlabel/netlabel_calipso.h | 9 ++++ 4 files changed, 150 insertions(+) diff --git a/include/net/netlabel.h b/include/net/netlabel.h index 2653d3a8cde8..2c0513b0cc88 100644 --- a/include/net/netlabel.h +++ b/include/net/netlabel.h @@ -237,6 +237,7 @@ struct netlbl_calipso_ops { int (*doi_add)(struct calipso_doi *doi_def, struct netlbl_audit *audit_info); void (*doi_free)(struct calipso_doi *doi_def); + int (*doi_remove)(u32 doi, struct netlbl_audit *audit_info); struct calipso_doi *(*doi_getdef)(u32 doi); void (*doi_putdef)(struct calipso_doi *doi_def); int (*doi_walk)(u32 *skip_cnt, diff --git a/net/ipv6/calipso.c b/net/ipv6/calipso.c index fa17c7a7f4be..d7df7a4bd32e 100644 --- a/net/ipv6/calipso.c +++ b/net/ipv6/calipso.c @@ -162,6 +162,53 @@ static void calipso_doi_free_rcu(struct rcu_head *entry) calipso_doi_free(doi_def); } +/** + * calipso_doi_remove - Remove an existing DOI from the CALIPSO protocol engine + * @doi: the DOI value + * @audit_secid: the LSM secid to use in the audit message + * + * Description: + * Removes a DOI definition from the CALIPSO engine. The NetLabel routines will + * be called to release their own LSM domain mappings as well as our own + * domain list. Returns zero on success and negative values on failure. + * + */ +static int calipso_doi_remove(u32 doi, struct netlbl_audit *audit_info) +{ + int ret_val; + struct calipso_doi *doi_def; + struct audit_buffer *audit_buf; + + spin_lock(&calipso_doi_list_lock); + doi_def = calipso_doi_search(doi); + if (!doi_def) { + spin_unlock(&calipso_doi_list_lock); + ret_val = -ENOENT; + goto doi_remove_return; + } + if (!atomic_dec_and_test(&doi_def->refcount)) { + spin_unlock(&calipso_doi_list_lock); + ret_val = -EBUSY; + goto doi_remove_return; + } + list_del_rcu(&doi_def->list); + spin_unlock(&calipso_doi_list_lock); + + call_rcu(&doi_def->rcu, calipso_doi_free_rcu); + ret_val = 0; + +doi_remove_return: + audit_buf = netlbl_audit_start(AUDIT_MAC_CALIPSO_DEL, audit_info); + if (audit_buf) { + audit_log_format(audit_buf, + " calipso_doi=%u res=%u", + doi, ret_val == 0 ? 1 : 0); + audit_log_end(audit_buf); + } + + return ret_val; +} + /** * calipso_doi_getdef - Returns a reference to a valid DOI definition * @doi: the DOI value @@ -253,6 +300,7 @@ static int calipso_doi_walk(u32 *skip_cnt, static const struct netlbl_calipso_ops ops = { .doi_add = calipso_doi_add, .doi_free = calipso_doi_free, + .doi_remove = calipso_doi_remove, .doi_getdef = calipso_doi_getdef, .doi_putdef = calipso_doi_putdef, .doi_walk = calipso_doi_walk, diff --git a/net/netlabel/netlabel_calipso.c b/net/netlabel/netlabel_calipso.c index 214114575812..2857673e8802 100644 --- a/net/netlabel/netlabel_calipso.c +++ b/net/netlabel/netlabel_calipso.c @@ -53,6 +53,12 @@ struct netlbl_calipso_doiwalk_arg { u32 seq; }; +/* Argument struct for netlbl_domhsh_walk() */ +struct netlbl_domhsh_walk_arg { + struct netlbl_audit *audit_info; + u32 doi; +}; + /* NetLabel Generic NETLINK CALIPSO family */ static struct genl_family netlbl_calipso_gnl_family = { .id = GENL_ID_GENERATE, @@ -257,6 +263,64 @@ static int netlbl_calipso_listall(struct sk_buff *skb, return skb->len; } +/** + * netlbl_calipso_remove_cb - netlbl_calipso_remove() callback for REMOVE + * @entry: LSM domain mapping entry + * @arg: the netlbl_domhsh_walk_arg structure + * + * Description: + * This function is intended for use by netlbl_calipso_remove() as the callback + * for the netlbl_domhsh_walk() function; it removes LSM domain map entries + * which are associated with the CALIPSO DOI specified in @arg. Returns zero on + * success, negative values on failure. + * + */ +static int netlbl_calipso_remove_cb(struct netlbl_dom_map *entry, void *arg) +{ + struct netlbl_domhsh_walk_arg *cb_arg = arg; + + if (entry->def.type == NETLBL_NLTYPE_CALIPSO && + entry->def.calipso->doi == cb_arg->doi) + return netlbl_domhsh_remove_entry(entry, cb_arg->audit_info); + + return 0; +} + +/** + * netlbl_calipso_remove - Handle a REMOVE message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated REMOVE message and respond accordingly. Returns + * zero on success, negative values on failure. + * + */ +static int netlbl_calipso_remove(struct sk_buff *skb, struct genl_info *info) +{ + int ret_val = -EINVAL; + struct netlbl_domhsh_walk_arg cb_arg; + struct netlbl_audit audit_info; + u32 skip_bkt = 0; + u32 skip_chain = 0; + + if (!info->attrs[NLBL_CALIPSO_A_DOI]) + return -EINVAL; + + netlbl_netlink_auditinfo(skb, &audit_info); + cb_arg.doi = nla_get_u32(info->attrs[NLBL_CALIPSO_A_DOI]); + cb_arg.audit_info = &audit_info; + ret_val = netlbl_domhsh_walk(&skip_bkt, &skip_chain, + netlbl_calipso_remove_cb, &cb_arg); + if (ret_val == 0 || ret_val == -ENOENT) { + ret_val = calipso_doi_remove(cb_arg.doi, &audit_info); + if (ret_val == 0) + atomic_dec(&netlabel_mgmt_protocount); + } + + return ret_val; +} + /* NetLabel Generic NETLINK Command Definitions */ @@ -269,6 +333,13 @@ static const struct genl_ops netlbl_calipso_ops[] = { .dumpit = NULL, }, { + .cmd = NLBL_CALIPSO_C_REMOVE, + .flags = GENL_ADMIN_PERM, + .policy = calipso_genl_policy, + .doit = netlbl_calipso_remove, + .dumpit = NULL, + }, + { .cmd = NLBL_CALIPSO_C_LIST, .flags = 0, .policy = calipso_genl_policy, @@ -362,6 +433,27 @@ void calipso_doi_free(struct calipso_doi *doi_def) ops->doi_free(doi_def); } +/** + * calipso_doi_remove - Remove an existing DOI from the CALIPSO protocol engine + * @doi: the DOI value + * @audit_secid: the LSM secid to use in the audit message + * + * Description: + * Removes a DOI definition from the CALIPSO engine. The NetLabel routines will + * be called to release their own LSM domain mappings as well as our own + * domain list. Returns zero on success and negative values on failure. + * + */ +int calipso_doi_remove(u32 doi, struct netlbl_audit *audit_info) +{ + int ret_val = -ENOMSG; + const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); + + if (ops) + ret_val = ops->doi_remove(doi, audit_info); + return ret_val; +} + /** * calipso_doi_getdef - Returns a reference to a valid DOI definition * @doi: the DOI value diff --git a/net/netlabel/netlabel_calipso.h b/net/netlabel/netlabel_calipso.h index 1f24174466e4..ed78554ba472 100644 --- a/net/netlabel/netlabel_calipso.h +++ b/net/netlabel/netlabel_calipso.h @@ -46,6 +46,14 @@ * * If using CALIPSO_MAP_PASS no additional attributes are required. * + * o REMOVE: + * Sent by an application to remove a specific DOI mapping table from the + * CALIPSO system. + * + * Required attributes: + * + * NLBL_CALIPSO_A_DOI + * * o LIST: * Sent by an application to list the details of a DOI definition. On * success the kernel should send a response using the following format. @@ -114,6 +122,7 @@ static inline int netlbl_calipso_genl_init(void) int calipso_doi_add(struct calipso_doi *doi_def, struct netlbl_audit *audit_info); void calipso_doi_free(struct calipso_doi *doi_def); +int calipso_doi_remove(u32 doi, struct netlbl_audit *audit_info); struct calipso_doi *calipso_doi_getdef(u32 doi); void calipso_doi_putdef(struct calipso_doi *doi_def); int calipso_doi_walk(u32 *skip_cnt, -- GitLab