netfilter: nft_quota: allow to restore consumed quota

Allow to restore consumed quota, this is useful to restore the quota
state across reboots.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_quota.c b/net/netfilter/nft_quota.c
index 7f27ebdce7ab83007fa908bf4e287f521e4936cb..bd6efc53f26d01d8c8ac246c36fa4b1cf970ce31 100644 (file)
--- a/net/netfilter/nft_quota.c
+++ b/net/netfilter/nft_quota.c
@@ -43,6 +43,7 @@ static inline void nft_quota_do_eval(struct nft_quota *priv,
 static const struct nla_policy nft_quota_policy[NFTA_QUOTA_MAX + 1] = {
        [NFTA_QUOTA_BYTES]      = { .type = NLA_U64 },
        [NFTA_QUOTA_FLAGS]      = { .type = NLA_U32 },
+       [NFTA_QUOTA_CONSUMED]   = { .type = NLA_U64 },
 };
 
 #define NFT_QUOTA_DEPLETED_BIT 1       /* From NFT_QUOTA_F_DEPLETED. */
@@ -68,7 +69,7 @@ static int nft_quota_do_init(const struct nlattr * const tb[],
                             struct nft_quota *priv)
 {
        unsigned long flags = 0;
-       u64 quota;
+       u64 quota, consumed = 0;
 
        if (!tb[NFTA_QUOTA_BYTES])
                return -EINVAL;
@@ -77,6 +78,12 @@ static int nft_quota_do_init(const struct nlattr * const tb[],
        if (quota > S64_MAX)
                return -EOVERFLOW;
 
+       if (tb[NFTA_QUOTA_CONSUMED]) {
+               consumed = be64_to_cpu(nla_get_be64(tb[NFTA_QUOTA_CONSUMED]));
+               if (consumed > quota)
+                       return -EINVAL;
+       }
+
        if (tb[NFTA_QUOTA_FLAGS]) {
                flags = ntohl(nla_get_be32(tb[NFTA_QUOTA_FLAGS]));
                if (flags & ~NFT_QUOTA_F_INV)
@@ -87,7 +94,7 @@ static int nft_quota_do_init(const struct nlattr * const tb[],
 
        priv->quota = quota;
        priv->flags = flags;
-       atomic64_set(&priv->consumed, 0);
+       atomic64_set(&priv->consumed, consumed);
 
        return 0;
 }