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author | 2018-12-13 16:01:29 +0100 | |
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committer | 2018-12-17 23:33:04 +0100 | |
commit | 203f2e78200c27e42e9f7d063091f950bf5fe4a0 (patch) | |
tree | 5249d1c4823cc4654004047c88edb5b5e246ce27 /net/netfilter/nf_nat_core.c | |
parent | netfilter: nat: un-export nf_nat_l4proto_unique_tuple (diff) | |
download | linux-203f2e78200c27e42e9f7d063091f950bf5fe4a0.tar.gz linux-203f2e78200c27e42e9f7d063091f950bf5fe4a0.tar.bz2 linux-203f2e78200c27e42e9f7d063091f950bf5fe4a0.zip |
netfilter: nat: remove l4proto->unique_tuple
fold remaining users (icmp, icmpv6, gre) into nf_nat_l4proto_unique_tuple.
The static-save of old incarnation of resolved key in gre and icmp is
removed as well, just use the prandom based offset like the others.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nf_nat_core.c')
-rw-r--r-- | net/netfilter/nf_nat_core.c | 69 |
1 files changed, 56 insertions, 13 deletions
diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 0c0f012343b1..763a92e82755 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -310,20 +310,65 @@ find_best_ips_proto(const struct nf_conntrack_zone *zone, } } +/* Alter the per-proto part of the tuple (depending on maniptype), to + * give a unique tuple in the given range if possible. + * + * Per-protocol part of tuple is initialized to the incoming packet. + */ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, const struct nf_nat_range2 *range, enum nf_nat_manip_type maniptype, const struct nf_conn *ct) { unsigned int range_size, min, max, i, attempts; - __be16 *portptr; + __be16 *keyptr; u16 off; static const unsigned int max_attempts = 128; - if (maniptype == NF_NAT_MANIP_SRC) - portptr = &tuple->src.u.all; - else - portptr = &tuple->dst.u.all; + switch (tuple->dst.protonum) { + case IPPROTO_ICMP: /* fallthrough */ + case IPPROTO_ICMPV6: + /* id is same for either direction... */ + keyptr = &tuple->src.u.icmp.id; + min = range->min_proto.icmp.id; + range_size = ntohs(range->max_proto.icmp.id) - + ntohs(range->min_proto.icmp.id) + 1; + goto find_free_id; +#if IS_ENABLED(CONFIG_NF_CT_PROTO_GRE) + case IPPROTO_GRE: + /* If there is no master conntrack we are not PPTP, + do not change tuples */ + if (!ct->master) + return; + + if (maniptype == NF_NAT_MANIP_SRC) + keyptr = &tuple->src.u.gre.key; + else + keyptr = &tuple->dst.u.gre.key; + + if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)) { + min = 1; + range_size = 65535; + } else { + min = ntohs(range->min_proto.gre.key); + range_size = ntohs(range->max_proto.gre.key) - min + 1; + } + goto find_free_id; +#endif + case IPPROTO_UDP: /* fallthrough */ + case IPPROTO_UDPLITE: /* fallthrough */ + case IPPROTO_TCP: /* fallthrough */ + case IPPROTO_SCTP: /* fallthrough */ + case IPPROTO_DCCP: /* fallthrough */ + if (maniptype == NF_NAT_MANIP_SRC) + keyptr = &tuple->src.u.all; + else + keyptr = &tuple->dst.u.all; + + break; + default: + return; + } /* If no range specified... */ if (!(range->flags & NF_NAT_RANGE_PROTO_SPECIFIED)) { @@ -331,9 +376,9 @@ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, if (maniptype == NF_NAT_MANIP_DST) return; - if (ntohs(*portptr) < 1024) { + if (ntohs(*keyptr) < 1024) { /* Loose convention: >> 512 is credential passing */ - if (ntohs(*portptr) < 512) { + if (ntohs(*keyptr) < 512) { min = 1; range_size = 511 - min + 1; } else { @@ -352,8 +397,9 @@ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, range_size = max - min + 1; } +find_free_id: if (range->flags & NF_NAT_RANGE_PROTO_OFFSET) - off = (ntohs(*portptr) - ntohs(range->base_proto.all)); + off = (ntohs(*keyptr) - ntohs(range->base_proto.all)); else off = prandom_u32(); @@ -369,7 +415,7 @@ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, */ another_round: for (i = 0; i < attempts; i++, off++) { - *portptr = htons(min + off % range_size); + *keyptr = htons(min + off % range_size); if (!nf_nat_used_tuple(tuple, ct)) return; } @@ -454,10 +500,7 @@ get_unique_tuple(struct nf_conntrack_tuple *tuple, } /* Last chance: get protocol to try to obtain unique tuple. */ - if (l4proto->unique_tuple) - l4proto->unique_tuple(l3proto, tuple, range, maniptype, ct); - else - nf_nat_l4proto_unique_tuple(tuple, range, maniptype, ct); + nf_nat_l4proto_unique_tuple(tuple, range, maniptype, ct); out: rcu_read_unlock(); } |