Commit e1ce69df authored by Huw Davies's avatar Huw Davies Committed by Paul Moore
Browse files

netlabel: Add support for enumerating the CALIPSO DOI list. 



Enumerate the DOI list through the NLBL_CALIPSO_C_LISTALL command.
It takes no attributes.

Signed-off-by: default avatarHuw Davies <huw@codeweavers.com>
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent a5e34490

include/net/netlabel.h

+4 −0
Original line number Diff line number Diff line
@@ -225,6 +225,7 @@ struct netlbl_lsm_secattr { 
 * @doi_free: free a CALIPSO DOI

 * @doi_getdef: returns a reference to a DOI

 * @doi_putdef: releases a reference of a DOI

 * @doi_walk: enumerate the DOI list

 *

 * Description:

 * This structure is filled out by the CALIPSO engine and passed
@@ -238,6 +239,9 @@ struct netlbl_calipso_ops { 
	void (*doi_free)(struct calipso_doi *doi_def);

	struct calipso_doi *(*doi_getdef)(u32 doi);

	void (*doi_putdef)(struct calipso_doi *doi_def);

	int (*doi_walk)(u32 *skip_cnt,

			int (*callback)(struct calipso_doi *doi_def, void *arg),

			void *cb_arg);

};



/*

net/ipv6/calipso.c

+41 −0
Original line number Diff line number Diff line
@@ -210,11 +210,52 @@ static void calipso_doi_putdef(struct calipso_doi *doi_def) 
	call_rcu(&doi_def->rcu, calipso_doi_free_rcu);

}



/**

 * calipso_doi_walk - Iterate through the DOI definitions

 * @skip_cnt: skip past this number of DOI definitions, updated

 * @callback: callback for each DOI definition

 * @cb_arg: argument for the callback function

 *

 * Description:

 * Iterate over the DOI definition list, skipping the first @skip_cnt entries.

 * For each entry call @callback, if @callback returns a negative value stop

 * 'walking' through the list and return.  Updates the value in @skip_cnt upon

 * return.  Returns zero on success, negative values on failure.

 *

 */

static int calipso_doi_walk(u32 *skip_cnt,

			    int (*callback)(struct calipso_doi *doi_def,

					    void *arg),

			    void *cb_arg)

{

	int ret_val = -ENOENT;

	u32 doi_cnt = 0;

	struct calipso_doi *iter_doi;



	rcu_read_lock();

	list_for_each_entry_rcu(iter_doi, &calipso_doi_list, list)

		if (atomic_read(&iter_doi->refcount) > 0) {

			if (doi_cnt++ < *skip_cnt)

				continue;

			ret_val = callback(iter_doi, cb_arg);

			if (ret_val < 0) {

				doi_cnt--;

				goto doi_walk_return;

			}

		}



doi_walk_return:

	rcu_read_unlock();

	*skip_cnt = doi_cnt;

	return ret_val;

}



static const struct netlbl_calipso_ops ops = {

	.doi_add          = calipso_doi_add,

	.doi_free         = calipso_doi_free,

	.doi_getdef       = calipso_doi_getdef,

	.doi_putdef       = calipso_doi_putdef,

	.doi_walk         = calipso_doi_walk,

};



/**

net/netlabel/netlabel_calipso.c

+106 −0
Original line number Diff line number Diff line
@@ -46,6 +46,13 @@ 
#include "netlabel_mgmt.h"

#include "netlabel_domainhash.h"



/* Argument struct for calipso_doi_walk() */

struct netlbl_calipso_doiwalk_arg {

	struct netlink_callback *nl_cb;

	struct sk_buff *skb;

	u32 seq;

};



/* NetLabel Generic NETLINK CALIPSO family */

static struct genl_family netlbl_calipso_gnl_family = {

	.id = GENL_ID_GENERATE,
@@ -183,6 +190,73 @@ static int netlbl_calipso_list(struct sk_buff *skb, struct genl_info *info) 
	return ret_val;

}



/**

 * netlbl_calipso_listall_cb - calipso_doi_walk() callback for LISTALL

 * @doi_def: the CALIPSO DOI definition

 * @arg: the netlbl_calipso_doiwalk_arg structure

 *

 * Description:

 * This function is designed to be used as a callback to the

 * calipso_doi_walk() function for use in generating a response for a LISTALL

 * message.  Returns the size of the message on success, negative values on

 * failure.

 *

 */

static int netlbl_calipso_listall_cb(struct calipso_doi *doi_def, void *arg)

{

	int ret_val = -ENOMEM;

	struct netlbl_calipso_doiwalk_arg *cb_arg = arg;

	void *data;



	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,

			   cb_arg->seq, &netlbl_calipso_gnl_family,

			   NLM_F_MULTI, NLBL_CALIPSO_C_LISTALL);

	if (!data)

		goto listall_cb_failure;



	ret_val = nla_put_u32(cb_arg->skb, NLBL_CALIPSO_A_DOI, doi_def->doi);

	if (ret_val != 0)

		goto listall_cb_failure;

	ret_val = nla_put_u32(cb_arg->skb,

			      NLBL_CALIPSO_A_MTYPE,

			      doi_def->type);

	if (ret_val != 0)

		goto listall_cb_failure;



	genlmsg_end(cb_arg->skb, data);

	return 0;



listall_cb_failure:

	genlmsg_cancel(cb_arg->skb, data);

	return ret_val;

}



/**

 * netlbl_calipso_listall - Handle a LISTALL message

 * @skb: the NETLINK buffer

 * @cb: the NETLINK callback

 *

 * Description:

 * Process a user generated LISTALL message and respond accordingly.  Returns

 * zero on success and negative values on error.

 *

 */

static int netlbl_calipso_listall(struct sk_buff *skb,

				  struct netlink_callback *cb)

{

	struct netlbl_calipso_doiwalk_arg cb_arg;

	u32 doi_skip = cb->args[0];



	cb_arg.nl_cb = cb;

	cb_arg.skb = skb;

	cb_arg.seq = cb->nlh->nlmsg_seq;



	calipso_doi_walk(&doi_skip, netlbl_calipso_listall_cb, &cb_arg);



	cb->args[0] = doi_skip;

	return skb->len;

}



/* NetLabel Generic NETLINK Command Definitions

 */
@@ -201,6 +275,13 @@ static const struct genl_ops netlbl_calipso_ops[] = { 
	.doit = netlbl_calipso_list,

	.dumpit = NULL,

	},

	{

	.cmd = NLBL_CALIPSO_C_LISTALL,

	.flags = 0,

	.policy = calipso_genl_policy,

	.doit = NULL,

	.dumpit = netlbl_calipso_listall,

	},

};



/* NetLabel Generic NETLINK Protocol Functions
@@ -316,3 +397,28 @@ void calipso_doi_putdef(struct calipso_doi *doi_def) 
	if (ops)

		ops->doi_putdef(doi_def);

}



/**

 * calipso_doi_walk - Iterate through the DOI definitions

 * @skip_cnt: skip past this number of DOI definitions, updated

 * @callback: callback for each DOI definition

 * @cb_arg: argument for the callback function

 *

 * Description:

 * Iterate over the DOI definition list, skipping the first @skip_cnt entries.

 * For each entry call @callback, if @callback returns a negative value stop

 * 'walking' through the list and return.  Updates the value in @skip_cnt upon

 * return.  Returns zero on success, negative values on failure.

 *

 */

int calipso_doi_walk(u32 *skip_cnt,

		     int (*callback)(struct calipso_doi *doi_def, void *arg),

		     void *cb_arg)

{

	int ret_val = -ENOMSG;

	const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get();



	if (ops)

		ret_val = ops->doi_walk(skip_cnt, callback, cb_arg);

	return ret_val;

}

net/netlabel/netlabel_calipso.h

+14 −0
Original line number Diff line number Diff line
@@ -63,6 +63,17 @@ 
 *

 *   If using CALIPSO_MAP_PASS no additional attributes are required.

 *

 * o LISTALL:

 *   This message is sent by an application to list the valid DOIs on the

 *   system.  When sent by an application there is no payload and the

 *   NLM_F_DUMP flag should be set.  The kernel should respond with a series of

 *   the following messages.

 *

 *   Required attributes:

 *

 *    NLBL_CALIPSO_A_DOI

 *    NLBL_CALIPSO_A_MTYPE

 *

 */



/* NetLabel CALIPSO commands */
@@ -105,5 +116,8 @@ int calipso_doi_add(struct calipso_doi *doi_def, 
void calipso_doi_free(struct calipso_doi *doi_def);

struct calipso_doi *calipso_doi_getdef(u32 doi);

void calipso_doi_putdef(struct calipso_doi *doi_def);

int calipso_doi_walk(u32 *skip_cnt,

		     int (*callback)(struct calipso_doi *doi_def, void *arg),

		     void *cb_arg);



#endif