Since YP protocol definition uses the constant to declare
variable-size opaque byte strings, the change should be binary
compatible with existing installations which do not expose keys or
values larger than 1024 bytes.
All uses of local variables with YPMAXRECORD sizes were removed to
avoid insane stack use. On the other hand, variables with static
lifetime should be fine and only result in increased VA use.
Glibc made same change, increasing the allowed length for keys and
values in YP to 16M, in 2013.
Reviewed by: markj
Discussed with: ian
Sponsored by: Mellanox Technologies
MFC after: 3 weeks
Differential revision: https://reviews.freebsd.org/D20900
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
and real life. YPPUSHPROC_XFRRESP is supposed to return void and take
an argument of type yppushresp_xfr, not the other way around as yp.x seems
to imply. (I spent two hours today staring intensely at my prototype ypxfr
code and scratching my head before I finally figured this out.)
taking an argument of type ypresp_key. This is incorrect: it should be
ypresp_nokey. (yp_first() is supposed to return the first key in a
given map; the server doesn't need any client-specified key to handle
such a request.)
No, not really. There are just a couple of long-standing bogosities here
that I feel compelled to fix. :)
There are two small changes here:
1) yp.x actually contains _three_ protocol definitions: YPPROG (standard
NIS client/server procedures), YPPUSH_XFRRESPPROG (callback handler
for the YPPROC_XFR service, aka ypxfr/yppush) and YPBINDPROG (for ypbind,
ypset & friends). The problem is that when you run yp.x through rpcgen(1),
it generates client and server stubs with hooks for all three services.
This makes it impossible to actually use the rpcgen-erated code in a
program that only deals with _one_ of these services (ypserv, ypbind,
etc...) without manually removing the unneeded stubs (either by hand
editing or by committing unspeakable horrors with sed). This defeats
the whole purpose of using rpcgen and is generally annoying.
What I've done is to insert a few #ifndefs and #endifs to allow a
programmer to selectively blot out those functions that aren't needed
for a particular program. For instance, if you do 'rpcgen -DYPSERV_ONLY',
you'll get only the necessary client/server stubs to implement the
standard yp client and server functions. If you do 'rpcgen -DYPBIND_ONLY',
you get only what you need for ypbind. If you don't #define anything,
you get the whole mess, just like before, so existing programs won't
notice the difference. (Note that the -D flag is not supported by our
existing crufty version of rpcgen, but I intend to update it soon.)
2) The definition for the ypresp_key_val structure is actually incorrect
with respect to reality: the key and val members are specified in the
wrong order. It should be val/key rather than key/val. For whatever
the reason, Sun's actual NIS implementation contradicts the protocol
definition in this case. Again, accounting for this bogosity here is
cleaner and easier than mangling the output from rpcgen.
