From: Florian Westphal <fw@xxxxxxxxx>
Historically this was net_random() based, and was then converted to
a hash based algorithm (private boot seed + hash of endpoint addresses)
due to concerns of leaking net_random() bits.
RANDOM_FULLY mode was added later to avoid problems with hash
based mode (see commit 34ce324019e76,
"netfilter: nf_nat: add full port randomization support" for details).
Just make prandom_u32() the default search starting point and get rid of
->secure_port() altogether.
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
include/net/netfilter/nf_nat_l3proto.h | 2 --
net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 7 -------
net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 7 -------
net/netfilter/nf_nat_proto_common.c | 9 ++-------
4 files changed, 2 insertions(+), 23 deletions(-)
diff --git a/include/net/netfilter/nf_nat_l3proto.h b/include/net/netfilter/nf_nat_l3proto.h
index d300b8f03972..f8b3fbe7a1bf 100644
--- a/include/net/netfilter/nf_nat_l3proto.h
+++ b/include/net/netfilter/nf_nat_l3proto.h
@@ -9,8 +9,6 @@ struct nf_nat_l3proto {
bool (*in_range)(const struct nf_conntrack_tuple *t,
const struct nf_nat_range2 *range);
- u32 (*secure_port)(const struct nf_conntrack_tuple *t, __be16);
-
bool (*manip_pkt)(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_nat_l4proto *l4proto,
diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
index 78a67f961d86..4d755a6f73ad 100644
--- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
@@ -69,12 +69,6 @@ static bool nf_nat_ipv4_in_range(const struct nf_conntrack_tuple *t,
ntohl(t->src.u3.ip) <= ntohl(range->max_addr.ip);
}
-static u32 nf_nat_ipv4_secure_port(const struct nf_conntrack_tuple *t,
- __be16 dport)
-{
- return secure_ipv4_port_ephemeral(t->src.u3.ip, t->dst.u3.ip, dport);
-}
-
static bool nf_nat_ipv4_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_nat_l4proto *l4proto,
@@ -162,7 +156,6 @@ static int nf_nat_ipv4_nlattr_to_range(struct nlattr *tb[],
static const struct nf_nat_l3proto nf_nat_l3proto_ipv4 = {
.l3proto = NFPROTO_IPV4,
.in_range = nf_nat_ipv4_in_range,
- .secure_port = nf_nat_ipv4_secure_port,
.manip_pkt = nf_nat_ipv4_manip_pkt,
.csum_update = nf_nat_ipv4_csum_update,
.csum_recalc = nf_nat_ipv4_csum_recalc,
diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
index ca6d38698b1a..290bb0142192 100644
--- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
@@ -68,12 +68,6 @@ static bool nf_nat_ipv6_in_range(const struct nf_conntrack_tuple *t,
ipv6_addr_cmp(&t->src.u3.in6, &range->max_addr.in6) <= 0;
}
-static u32 nf_nat_ipv6_secure_port(const struct nf_conntrack_tuple *t,
- __be16 dport)
-{
- return secure_ipv6_port_ephemeral(t->src.u3.ip6, t->dst.u3.ip6, dport);
-}
-
static bool nf_nat_ipv6_manip_pkt(struct sk_buff *skb,
unsigned int iphdroff,
const struct nf_nat_l4proto *l4proto,
@@ -171,7 +165,6 @@ static int nf_nat_ipv6_nlattr_to_range(struct nlattr *tb[],
static const struct nf_nat_l3proto nf_nat_l3proto_ipv6 = {
.l3proto = NFPROTO_IPV6,
- .secure_port = nf_nat_ipv6_secure_port,
.in_range = nf_nat_ipv6_in_range,
.manip_pkt = nf_nat_ipv6_manip_pkt,
.csum_update = nf_nat_ipv6_csum_update,
diff --git a/net/netfilter/nf_nat_proto_common.c b/net/netfilter/nf_nat_proto_common.c
index dcb5d11688a1..dabfe9a2c041 100644
--- a/net/netfilter/nf_nat_proto_common.c
+++ b/net/netfilter/nf_nat_proto_common.c
@@ -77,15 +77,10 @@ void nf_nat_l4proto_unique_tuple(const struct nf_nat_l3proto *l3proto,
range_size = max - min + 1;
}
- if (range->flags & NF_NAT_RANGE_PROTO_RANDOM) {
- off = l3proto->secure_port(tuple, maniptype == NF_NAT_MANIP_SRC
- ? tuple->dst.u.all
- : tuple->src.u.all);
- } else if (range->flags & NF_NAT_RANGE_PROTO_OFFSET) {
+ if (range->flags & NF_NAT_RANGE_PROTO_OFFSET)
off = (ntohs(*portptr) - ntohs(range->base_proto.all));
- } else {
+ else
off = prandom_u32();
- }
attempts = range_size;
if (attempts > max_attempts)
--
2.11.0
