Hi,
In general it is a bad idea to use one random secret for two things.
The inet PCB uses one hash with local and foreign addresses, and
one with local port numbers. Give both hashes separate keys. Also
document the struct fields.
ok?
bluhm
Index: netinet/in_pcb.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/in_pcb.c,v
retrieving revision 1.244
diff -u -p -r1.244 in_pcb.c
--- netinet/in_pcb.c 13 Sep 2018 19:53:58 -0000 1.244
+++ netinet/in_pcb.c 13 Sep 2018 20:53:22 -0000
@@ -148,7 +148,7 @@ in_pcblhash(struct inpcbtable *table, in
SIPHASH_CTX ctx;
u_int32_t nrdom = htonl(rdom);
- SipHash24_Init(&ctx, &table->inpt_key);
+ SipHash24_Init(&ctx, &table->inpt_lkey);
SipHash24_Update(&ctx, &nrdom, sizeof(nrdom));
SipHash24_Update(&ctx, &lport, sizeof(lport));
@@ -171,6 +171,7 @@ in_pcbinit(struct inpcbtable *table, int
table->inpt_count = 0;
table->inpt_size = hashsize;
arc4random_buf(&table->inpt_key, sizeof(table->inpt_key));
+ arc4random_buf(&table->inpt_lkey, sizeof(table->inpt_lkey));
}
/*
@@ -999,6 +1000,7 @@ in_pcbresize(struct inpcbtable *table, i
table->inpt_lmask = nlmask;
table->inpt_size = hashsize;
arc4random_buf(&table->inpt_key, sizeof(table->inpt_key));
+ arc4random_buf(&table->inpt_lkey, sizeof(table->inpt_lkey));
TAILQ_FOREACH(inp, &table->inpt_queue, inp_queue) {
in_pcbrehash(inp);
Index: netinet/in_pcb.h
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/in_pcb.h,v
retrieving revision 1.111
diff -u -p -r1.111 in_pcb.h
--- netinet/in_pcb.h 13 Sep 2018 19:53:58 -0000 1.111
+++ netinet/in_pcb.h 13 Sep 2018 21:09:33 -0000
@@ -90,10 +90,10 @@ union inpaddru {
* control block.
*/
struct inpcb {
- LIST_ENTRY(inpcb) inp_hash;
- LIST_ENTRY(inpcb) inp_lhash; /* extra hash for lport */
- TAILQ_ENTRY(inpcb) inp_queue;
- struct inpcbtable *inp_table;
+ LIST_ENTRY(inpcb) inp_hash; /* local and foreign hash */
+ LIST_ENTRY(inpcb) inp_lhash; /* locol port hash */
+ TAILQ_ENTRY(inpcb) inp_queue; /* inet PCB queue */
+ struct inpcbtable *inp_table; /* inet queue/hash table */
union inpaddru inp_faddru; /* Foreign address. */
union inpaddru inp_laddru; /* Local address. */
#define inp_faddr inp_faddru.iau_a4u.inaddr
@@ -149,11 +149,12 @@ struct inpcb {
LIST_HEAD(inpcbhead, inpcb);
struct inpcbtable {
- TAILQ_HEAD(inpthead, inpcb) inpt_queue;
- struct inpcbhead *inpt_hashtbl, *inpt_lhashtbl;
- SIPHASH_KEY inpt_key;
- u_long inpt_mask, inpt_lmask;
- int inpt_count, inpt_size;
+ TAILQ_HEAD(inpthead, inpcb) inpt_queue; /* inet PCB queue */
+ struct inpcbhead *inpt_hashtbl; /* local and foreign hash */
+ struct inpcbhead *inpt_lhashtbl; /* local port hash */
+ SIPHASH_KEY inpt_key, inpt_lkey; /* secrets for hashes */
+ u_long inpt_mask, inpt_lmask; /* hash masks */
+ int inpt_count, inpt_size; /* queue count, hash size */
};
/* flags in inp_flags: */
