[NetLabel]: rework the Netlink attribute handling (part 2)

At the suggestion of Thomas Graf, rewrite NetLabel's use of Netlink attributes
to better follow the common Netlink attribute usage.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 35 insertions, 44 deletions

diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 785f4960e0d3..440f5c4e1e2d 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -55,9 +55,13 @@ static struct genl_family netlbl_unlabel_gnl_family = {
         .hdrsize = 0,
         .name = NETLBL_NLTYPE_UNLABELED_NAME,
         .version = NETLBL_PROTO_VERSION,
-        .maxattr = 0,
+        .maxattr = NLBL_UNLABEL_A_MAX,
 };
 
+/* NetLabel Netlink attribute policy */
+static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
+        [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
+};
 
 /*
  * NetLabel Command Handlers
@@ -75,31 +79,18 @@ static struct genl_family netlbl_unlabel_gnl_family = {
  */
 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 {
-        int ret_val;
-        struct nlattr *data = netlbl_netlink_payload_data(skb);
-        u32 value;
-
-        ret_val = netlbl_netlink_cap_check(skb, CAP_NET_ADMIN);
-        if (ret_val != 0)
-                return ret_val;
+        int ret_val = -EINVAL;
+        u8 value;
 
-        if (netlbl_netlink_payload_len(skb) == NETLBL_LEN_U32) {
-                value = nla_get_u32(data);
+        if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
+                value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
                 if (value == 1 || value == 0) {
                         atomic_set(&netlabel_unlabel_accept_flg, value);
-                        netlbl_netlink_send_ack(info,
-                                                netlbl_unlabel_gnl_family.id,
-                                                NLBL_UNLABEL_C_ACK,
-                                                NETLBL_E_OK);
-                        return 0;
+                        ret_val = 0;
                 }
         }
 
-        netlbl_netlink_send_ack(info,
-                                netlbl_unlabel_gnl_family.id,
-                                NLBL_UNLABEL_C_ACK,
-                                EINVAL);
-        return -EINVAL;
+        return ret_val;
 }
 
 /**
@@ -114,39 +105,39 @@ static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
  */
 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
 {
-        int ret_val = -ENOMEM;
+        int ret_val = -EINVAL;
         struct sk_buff *ans_skb;
+        void *data;
 
-        ans_skb = netlbl_netlink_alloc_skb(0,
-                                           GENL_HDRLEN + NETLBL_LEN_U32,
-                                           GFP_KERNEL);
+        ans_skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
         if (ans_skb == NULL)
                 goto list_failure;
-
-        if (netlbl_netlink_hdr_put(ans_skb,
-                                   info->snd_pid,
-                                   0,
-                                   netlbl_unlabel_gnl_family.id,
-                                   NLBL_UNLABEL_C_LIST) == NULL)
+        data = netlbl_netlink_hdr_put(ans_skb,
+                                      info->snd_pid,
+                                      info->snd_seq,
+                                      netlbl_unlabel_gnl_family.id,
+                                      0,
+                                      NLBL_UNLABEL_C_LIST);
+        if (data == NULL) {
+                ret_val = -ENOMEM;
                 goto list_failure;
+        }
 
-        ret_val = nla_put_u32(ans_skb,
-                              NLA_U32,
-                              atomic_read(&netlabel_unlabel_accept_flg));
+        ret_val = nla_put_u8(ans_skb,
+                             NLBL_UNLABEL_A_ACPTFLG,
+                             atomic_read(&netlabel_unlabel_accept_flg));
         if (ret_val != 0)
                 goto list_failure;
 
-        ret_val = netlbl_netlink_snd(ans_skb, info->snd_pid);
+        genlmsg_end(ans_skb, data);
+
+        ret_val = genlmsg_unicast(ans_skb, info->snd_pid);
         if (ret_val != 0)
                 goto list_failure;
-
         return 0;
 
 list_failure:
-        netlbl_netlink_send_ack(info,
-                                netlbl_unlabel_gnl_family.id,
-                                NLBL_UNLABEL_C_ACK,
-                                -ret_val);
+        kfree(ans_skb);
         return ret_val;
 }
 
@@ -157,7 +148,8 @@ list_failure:
 
 static struct genl_ops netlbl_unlabel_genl_c_accept = {
         .cmd = NLBL_UNLABEL_C_ACCEPT,
-        .flags = 0,
+        .flags = GENL_ADMIN_PERM,
+        .policy = netlbl_unlabel_genl_policy,
         .doit = netlbl_unlabel_accept,
         .dumpit = NULL,
 };
@@ -165,6 +157,7 @@ static struct genl_ops netlbl_unlabel_genl_c_accept = {
 static struct genl_ops netlbl_unlabel_genl_c_list = {
         .cmd = NLBL_UNLABEL_C_LIST,
         .flags = 0,
+        .policy = netlbl_unlabel_genl_policy,
         .doit = netlbl_unlabel_list,
         .dumpit = NULL,
 };
@@ -218,10 +211,8 @@ int netlbl_unlabel_genl_init(void)
  */
 int netlbl_unlabel_getattr(struct netlbl_lsm_secattr *secattr)
 {
-        if (atomic_read(&netlabel_unlabel_accept_flg) == 1) {
-                memset(secattr, 0, sizeof(*secattr));
-                return 0;
-        }
+        if (atomic_read(&netlabel_unlabel_accept_flg) == 1)
+                return netlbl_secattr_init(secattr);
 
         return -ENOMSG;
 }