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const sockaddr in tcp syn cache
> On 25 Jan 2024, at 02:47, Alexander Bluhm <alexander.bluhm@gmx.net> wrote:
>
> On Fri, Jan 19, 2024 at 03:01:12PM +0100, Alexander Bluhm wrote:
>> On Fri, Jan 19, 2024 at 02:47:53PM +0100, Alexander Bluhm wrote:
>>> tcp6_ctlinput() casts a constant sockaddr_sin6 to non-const sockaddr.
>>> sa6_src may be &sa6_any which lives in read-only data section.
>>>
>>> Better pass down the const addresses to tcp syn cache. We only need
>>> them for lookup.
>>
>> Oops, missed one satosin_const which breaks non-INET6 builds.
>>
>> updated diff, ok?
>
> anyone?
>
ok mvs
>> Index: netinet/tcp_input.c
>> ===================================================================
>> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_input.c,v
>> diff -u -p -r1.398 tcp_input.c
>> --- netinet/tcp_input.c 11 Jan 2024 13:49:49 -0000 1.398
>> +++ netinet/tcp_input.c 19 Jan 2024 13:56:41 -0000
>> @@ -201,8 +201,8 @@ int syn_cache_add(struct sockaddr *, st
>> struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *,
>> struct tcphdr *, unsigned int, unsigned int, struct socket *,
>> struct mbuf *, uint64_t);
>> -struct syn_cache *syn_cache_lookup(struct sockaddr *, struct sockaddr *,
>> - struct syn_cache_head **, u_int);
>> +struct syn_cache *syn_cache_lookup(const struct sockaddr *,
>> + const struct sockaddr *, struct syn_cache_head **, u_int);
>>
>> /*
>> * Insert segment ti into reassembly queue of tcp with
>> @@ -3109,9 +3109,9 @@ struct mutex syn_cache_mtx = MUTEX_INITI
>> #ifndef INET6
>> #define SYN_HASHALL(hash, src, dst, rand) \
>> do { \
>> - hash = SYN_HASH(&satosin(src)->sin_addr, \
>> - satosin(src)->sin_port, \
>> - satosin(dst)->sin_port, (rand)); \
>> + hash = SYN_HASH(&satosin_const(src)->sin_addr, \
>> + satosin_const(src)->sin_port, \
>> + satosin_const(dst)->sin_port, (rand)); \
>> } while (/*CONSTCOND*/ 0)
>> #else
>> #define SYN_HASH6(sa, sp, dp, rand) \
>> @@ -3125,14 +3125,14 @@ do { \
>> do { \
>> switch ((src)->sa_family) { \
>> case AF_INET: \
>> - hash = SYN_HASH(&satosin(src)->sin_addr, \
>> - satosin(src)->sin_port, \
>> - satosin(dst)->sin_port, (rand)); \
>> + hash = SYN_HASH(&satosin_const(src)->sin_addr, \
>> + satosin_const(src)->sin_port, \
>> + satosin_const(dst)->sin_port, (rand)); \
>> break; \
>> case AF_INET6: \
>> - hash = SYN_HASH6(&satosin6(src)->sin6_addr, \
>> - satosin6(src)->sin6_port, \
>> - satosin6(dst)->sin6_port, (rand)); \
>> + hash = SYN_HASH6(&satosin6_const(src)->sin6_addr, \
>> + satosin6_const(src)->sin6_port, \
>> + satosin6_const(dst)->sin6_port, (rand)); \
>> break; \
>> default: \
>> hash = 0; \
>> @@ -3423,7 +3423,7 @@ syn_cache_cleanup(struct tcpcb *tp)
>> * Find an entry in the syn cache.
>> */
>> struct syn_cache *
>> -syn_cache_lookup(struct sockaddr *src, struct sockaddr *dst,
>> +syn_cache_lookup(const struct sockaddr *src, const struct sockaddr *dst,
>> struct syn_cache_head **headp, u_int rtableid)
>> {
>> struct syn_cache_set *sets[2];
>> @@ -3709,8 +3709,8 @@ syn_cache_reset(struct sockaddr *src, st
>> }
>>
>> void
>> -syn_cache_unreach(struct sockaddr *src, struct sockaddr *dst, struct tcphdr *th,
>> - u_int rtableid)
>> +syn_cache_unreach(const struct sockaddr *src, const struct sockaddr *dst,
>> + struct tcphdr *th, u_int rtableid)
>> {
>> struct syn_cache *sc;
>> struct syn_cache_head *scp;
>> Index: netinet/tcp_subr.c
>> ===================================================================
>> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_subr.c,v
>> diff -u -p -r1.195 tcp_subr.c
>> --- netinet/tcp_subr.c 11 Jan 2024 13:49:49 -0000 1.195
>> +++ netinet/tcp_subr.c 19 Jan 2024 13:37:29 -0000
>> @@ -698,8 +698,8 @@ tcp6_ctlinput(int cmd, struct sockaddr *
>> } else if (inet6ctlerrmap[cmd] == EHOSTUNREACH ||
>> inet6ctlerrmap[cmd] == ENETUNREACH ||
>> inet6ctlerrmap[cmd] == EHOSTDOWN)
>> - syn_cache_unreach((struct sockaddr *)sa6_src,
>> - sa, &th, rdomain);
>> + syn_cache_unreach(sin6tosa_const(sa6_src), sa, &th,
>> + rdomain);
>> in_pcbunref(inp);
>> } else {
>> in6_pcbnotify(&tcbtable, sa6, 0,
>> Index: netinet/tcp_var.h
>> ===================================================================
>> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_var.h,v
>> diff -u -p -r1.174 tcp_var.h
>> --- netinet/tcp_var.h 11 Jan 2024 13:49:49 -0000 1.174
>> +++ netinet/tcp_var.h 19 Jan 2024 13:37:29 -0000
>> @@ -799,7 +799,7 @@ int tcp_signature(struct tdb *, int, str
>> #endif /* TCP_SIGNATURE */
>> void tcp_set_iss_tsm(struct tcpcb *);
>>
>> -void syn_cache_unreach(struct sockaddr *, struct sockaddr *,
>> +void syn_cache_unreach(const struct sockaddr *, const struct sockaddr *,
>> struct tcphdr *, u_int);
>> void syn_cache_init(void);
>> void syn_cache_cleanup(struct tcpcb *);
>> Index: netinet6/in6.h
>> ===================================================================
>> RCS file: /data/mirror/openbsd/cvs/src/sys/netinet6/in6.h,v
>> diff -u -p -r1.111 in6.h
>> --- netinet6/in6.h 28 Nov 2023 13:23:20 -0000 1.111
>> +++ netinet6/in6.h 19 Jan 2024 13:37:29 -0000
>> @@ -459,6 +459,12 @@ sin6tosa(struct sockaddr_in6 *sin6)
>> return ((struct sockaddr *)(sin6));
>> }
>>
>> +static inline const struct sockaddr *
>> +sin6tosa_const(const struct sockaddr_in6 *sin6)
>> +{
>> + return ((const struct sockaddr *)(sin6));
>> +}
>> +
>> static inline struct in6_ifaddr *
>> ifatoia6(struct ifaddr *ifa)
>> {
>
const sockaddr in tcp syn cache