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authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /sunrpc/svc_udp.c
downloadglibc-28f540f45bbacd939bfd07f213bcad2bf730b1bf.tar.gz
initial import
Diffstat (limited to 'sunrpc/svc_udp.c')
-rw-r--r--sunrpc/svc_udp.c475
1 files changed, 475 insertions, 0 deletions
diff --git a/sunrpc/svc_udp.c b/sunrpc/svc_udp.c
new file mode 100644
index 0000000000..69ef7a1ce3
--- /dev/null
+++ b/sunrpc/svc_udp.c
@@ -0,0 +1,475 @@
+/* @(#)svc_udp.c 2.2 88/07/29 4.0 RPCSRC */
+/*
+ * 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(lint) && defined(SCCSIDS)
+static char sccsid[] = "@(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";
+#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 <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 struct xp_ops svcudp_op = {
+ svcudp_recv,
+ svcudp_stat,
+ svcudp_getargs,
+ svcudp_reply,
+ svcudp_freeargs,
+ svcudp_destroy
+};
+
+extern int errno;
+
+/*
+ * 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;
+ }
+ bzero((char *)&addr, sizeof (addr));
+ 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 < 4*sizeof(u_long))
+ 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) \
+ bzero((char *) addr, 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.
+ */
+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
+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
+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) (bcmp((char*)&a1, (char*)&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);
+}
+