freebsd-dev/lib/libc/rpc/svc_udp.c
Bill Paul ad133ed648 Resolve conflicts.
This concludes tonight's entertainment. Once I'm sure I haven't destroyed
the world with all these changes, I'll import the utilities. Everything
should continue to work as before. If it doesn't let me know.

Special thanks to Mark Murray for running a test 'make world' for me to
shake out the bugs, which, hopefully, I have fixed.

(And there was much rejoicing.)
1997-05-28 05:05:31 +00:00

481 lines
12 KiB
C

/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";*/
/*static char *sccsid = "from: @(#)svc_udp.c 2.2 88/07/29 4.0 RPCSRC";*/
static char *rcsid = "$Id: svc_udp.c,v 1.7 1996/12/30 15:21:19 peter Exp $";
#endif
/*
* svc_udp.c,
* Server side for UDP/IP based RPC. (Does some caching in the hopes of
* achieving execute-at-most-once semantics.)
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <errno.h>
#define rpc_buffer(xprt) ((xprt)->xp_p1)
#define MAX(a, b) ((a > b) ? a : b)
static bool_t svcudp_recv();
static bool_t svcudp_reply();
static enum xprt_stat svcudp_stat();
static bool_t svcudp_getargs();
static bool_t svcudp_freeargs();
static void svcudp_destroy();
static void cache_set __P((SVCXPRT *, u_long));
static int cache_get __P((SVCXPRT *, struct rpc_msg *, char **, u_long *));
static struct xp_ops svcudp_op = {
svcudp_recv,
svcudp_stat,
svcudp_getargs,
svcudp_reply,
svcudp_freeargs,
svcudp_destroy
};
/*
* kept in xprt->xp_p2
*/
struct svcudp_data {
u_int su_iosz; /* byte size of send.recv buffer */
u_long su_xid; /* transaction id */
XDR su_xdrs; /* XDR handle */
char su_verfbody[MAX_AUTH_BYTES]; /* verifier body */
char * su_cache; /* cached data, NULL if no cache */
};
#define su_data(xprt) ((struct svcudp_data *)(xprt->xp_p2))
/*
* Usage:
* xprt = svcudp_create(sock);
*
* If sock<0 then a socket is created, else sock is used.
* If the socket, sock is not bound to a port then svcudp_create
* binds it to an arbitrary port. In any (successful) case,
* xprt->xp_sock is the registered socket number and xprt->xp_port is the
* associated port number.
* Once *xprt is initialized, it is registered as a transporter;
* see (svc.h, xprt_register).
* The routines returns NULL if a problem occurred.
*/
SVCXPRT *
svcudp_bufcreate(sock, sendsz, recvsz)
register int sock;
u_int sendsz, recvsz;
{
bool_t madesock = FALSE;
register SVCXPRT *xprt;
register struct svcudp_data *su;
struct sockaddr_in addr;
int len = sizeof(struct sockaddr_in);
if (sock == RPC_ANYSOCK) {
if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
perror("svcudp_create: socket creation problem");
return ((SVCXPRT *)NULL);
}
madesock = TRUE;
}
memset((char *)&addr, 0, sizeof (addr));
addr.sin_len = sizeof(struct sockaddr_in);
addr.sin_family = AF_INET;
if (bindresvport(sock, &addr)) {
addr.sin_port = 0;
(void)bind(sock, (struct sockaddr *)&addr, len);
}
if (getsockname(sock, (struct sockaddr *)&addr, &len) != 0) {
perror("svcudp_create - cannot getsockname");
if (madesock)
(void)close(sock);
return ((SVCXPRT *)NULL);
}
xprt = (SVCXPRT *)mem_alloc(sizeof(SVCXPRT));
if (xprt == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
return (NULL);
}
su = (struct svcudp_data *)mem_alloc(sizeof(*su));
if (su == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
return (NULL);
}
su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
return (NULL);
}
xdrmem_create(
&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
su->su_cache = NULL;
xprt->xp_p2 = (caddr_t)su;
xprt->xp_verf.oa_base = su->su_verfbody;
xprt->xp_ops = &svcudp_op;
xprt->xp_port = ntohs(addr.sin_port);
xprt->xp_sock = sock;
xprt_register(xprt);
return (xprt);
}
SVCXPRT *
svcudp_create(sock)
int sock;
{
return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
}
static enum xprt_stat
svcudp_stat(xprt)
SVCXPRT *xprt;
{
return (XPRT_IDLE);
}
static bool_t
svcudp_recv(xprt, msg)
register SVCXPRT *xprt;
struct rpc_msg *msg;
{
register struct svcudp_data *su = su_data(xprt);
register XDR *xdrs = &(su->su_xdrs);
register int rlen;
char *reply;
u_long replylen;
again:
xprt->xp_addrlen = sizeof(struct sockaddr_in);
rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz,
0, (struct sockaddr *)&(xprt->xp_raddr), &(xprt->xp_addrlen));
if (rlen == -1 && errno == EINTR)
goto again;
if (rlen == -1 || rlen < 4*sizeof(u_int32_t))
return (FALSE);
xdrs->x_op = XDR_DECODE;
XDR_SETPOS(xdrs, 0);
if (! xdr_callmsg(xdrs, msg))
return (FALSE);
su->su_xid = msg->rm_xid;
if (su->su_cache != NULL) {
if (cache_get(xprt, msg, &reply, &replylen)) {
(void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
(struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
return (TRUE);
}
}
return (TRUE);
}
static bool_t
svcudp_reply(xprt, msg)
register SVCXPRT *xprt;
struct rpc_msg *msg;
{
register struct svcudp_data *su = su_data(xprt);
register XDR *xdrs = &(su->su_xdrs);
register int slen;
register bool_t stat = FALSE;
xdrs->x_op = XDR_ENCODE;
XDR_SETPOS(xdrs, 0);
msg->rm_xid = su->su_xid;
if (xdr_replymsg(xdrs, msg)) {
slen = (int)XDR_GETPOS(xdrs);
if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
(struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
== slen) {
stat = TRUE;
if (su->su_cache && slen >= 0) {
cache_set(xprt, (u_long) slen);
}
}
}
return (stat);
}
static bool_t
svcudp_getargs(xprt, xdr_args, args_ptr)
SVCXPRT *xprt;
xdrproc_t xdr_args;
caddr_t args_ptr;
{
return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr));
}
static bool_t
svcudp_freeargs(xprt, xdr_args, args_ptr)
SVCXPRT *xprt;
xdrproc_t xdr_args;
caddr_t args_ptr;
{
register XDR *xdrs = &(su_data(xprt)->su_xdrs);
xdrs->x_op = XDR_FREE;
return ((*xdr_args)(xdrs, args_ptr));
}
static void
svcudp_destroy(xprt)
register SVCXPRT *xprt;
{
register struct svcudp_data *su = su_data(xprt);
xprt_unregister(xprt);
(void)close(xprt->xp_sock);
XDR_DESTROY(&(su->su_xdrs));
mem_free(rpc_buffer(xprt), su->su_iosz);
mem_free((caddr_t)su, sizeof(struct svcudp_data));
mem_free((caddr_t)xprt, sizeof(SVCXPRT));
}
/***********this could be a separate file*********************/
/*
* Fifo cache for udp server
* Copies pointers to reply buffers into fifo cache
* Buffers are sent again if retransmissions are detected.
*/
#define SPARSENESS 4 /* 75% sparse */
#define CACHE_PERROR(msg) \
(void) fprintf(stderr,"%s\n", msg)
#define ALLOC(type, size) \
(type *) mem_alloc((unsigned) (sizeof(type) * (size)))
#define BZERO(addr, type, size) \
memset((char *) addr, 0, sizeof(type) * (int) (size))
/*
* An entry in the cache
*/
typedef struct cache_node *cache_ptr;
struct cache_node {
/*
* Index into cache is xid, proc, vers, prog and address
*/
u_long cache_xid;
u_long cache_proc;
u_long cache_vers;
u_long cache_prog;
struct sockaddr_in cache_addr;
/*
* The cached reply and length
*/
char * cache_reply;
u_long cache_replylen;
/*
* Next node on the list, if there is a collision
*/
cache_ptr cache_next;
};
/*
* The entire cache
*/
struct udp_cache {
u_long uc_size; /* size of cache */
cache_ptr *uc_entries; /* hash table of entries in cache */
cache_ptr *uc_fifo; /* fifo list of entries in cache */
u_long uc_nextvictim; /* points to next victim in fifo list */
u_long uc_prog; /* saved program number */
u_long uc_vers; /* saved version number */
u_long uc_proc; /* saved procedure number */
struct sockaddr_in uc_addr; /* saved caller's address */
};
/*
* the hashing function
*/
#define CACHE_LOC(transp, xid) \
(xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
/*
* Enable use of the cache.
* Note: there is no disable.
*/
int svcudp_enablecache(transp, size)
SVCXPRT *transp;
u_long size;
{
struct svcudp_data *su = su_data(transp);
struct udp_cache *uc;
if (su->su_cache != NULL) {
CACHE_PERROR("enablecache: cache already enabled");
return(0);
}
uc = ALLOC(struct udp_cache, 1);
if (uc == NULL) {
CACHE_PERROR("enablecache: could not allocate cache");
return(0);
}
uc->uc_size = size;
uc->uc_nextvictim = 0;
uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
if (uc->uc_entries == NULL) {
CACHE_PERROR("enablecache: could not allocate cache data");
return(0);
}
BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
uc->uc_fifo = ALLOC(cache_ptr, size);
if (uc->uc_fifo == NULL) {
CACHE_PERROR("enablecache: could not allocate cache fifo");
return(0);
}
BZERO(uc->uc_fifo, cache_ptr, size);
su->su_cache = (char *) uc;
return(1);
}
/*
* Set an entry in the cache
*/
static void
cache_set(xprt, replylen)
SVCXPRT *xprt;
u_long replylen;
{
register cache_ptr victim;
register cache_ptr *vicp;
register struct svcudp_data *su = su_data(xprt);
struct udp_cache *uc = (struct udp_cache *) su->su_cache;
u_int loc;
char *newbuf;
/*
* Find space for the new entry, either by
* reusing an old entry, or by mallocing a new one
*/
victim = uc->uc_fifo[uc->uc_nextvictim];
if (victim != NULL) {
loc = CACHE_LOC(xprt, victim->cache_xid);
for (vicp = &uc->uc_entries[loc];
*vicp != NULL && *vicp != victim;
vicp = &(*vicp)->cache_next)
;
if (*vicp == NULL) {
CACHE_PERROR("cache_set: victim not found");
return;
}
*vicp = victim->cache_next; /* remote from cache */
newbuf = victim->cache_reply;
} else {
victim = ALLOC(struct cache_node, 1);
if (victim == NULL) {
CACHE_PERROR("cache_set: victim alloc failed");
return;
}
newbuf = mem_alloc(su->su_iosz);
if (newbuf == NULL) {
CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
return;
}
}
/*
* Store it away
*/
victim->cache_replylen = replylen;
victim->cache_reply = rpc_buffer(xprt);
rpc_buffer(xprt) = newbuf;
xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_ENCODE);
victim->cache_xid = su->su_xid;
victim->cache_proc = uc->uc_proc;
victim->cache_vers = uc->uc_vers;
victim->cache_prog = uc->uc_prog;
victim->cache_addr = uc->uc_addr;
loc = CACHE_LOC(xprt, victim->cache_xid);
victim->cache_next = uc->uc_entries[loc];
uc->uc_entries[loc] = victim;
uc->uc_fifo[uc->uc_nextvictim++] = victim;
uc->uc_nextvictim %= uc->uc_size;
}
/*
* Try to get an entry from the cache
* return 1 if found, 0 if not found
*/
static int
cache_get(xprt, msg, replyp, replylenp)
SVCXPRT *xprt;
struct rpc_msg *msg;
char **replyp;
u_long *replylenp;
{
u_int loc;
register cache_ptr ent;
register struct svcudp_data *su = su_data(xprt);
register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
# define EQADDR(a1, a2) (memcmp(&a1, &a2, sizeof(a1)) == 0)
loc = CACHE_LOC(xprt, su->su_xid);
for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
if (ent->cache_xid == su->su_xid &&
ent->cache_proc == uc->uc_proc &&
ent->cache_vers == uc->uc_vers &&
ent->cache_prog == uc->uc_prog &&
EQADDR(ent->cache_addr, uc->uc_addr)) {
*replyp = ent->cache_reply;
*replylenp = ent->cache_replylen;
return(1);
}
}
/*
* Failed to find entry
* Remember a few things so we can do a set later
*/
uc->uc_proc = msg->rm_call.cb_proc;
uc->uc_vers = msg->rm_call.cb_vers;
uc->uc_prog = msg->rm_call.cb_prog;
uc->uc_addr = xprt->xp_raddr;
return(0);
}