diff options
Diffstat (limited to 'lib/libc/rpc/svc_udp.c')
-rw-r--r-- | lib/libc/rpc/svc_udp.c | 482 |
1 files changed, 482 insertions, 0 deletions
diff --git a/lib/libc/rpc/svc_udp.c b/lib/libc/rpc/svc_udp.c new file mode 100644 index 0000000..b071355 --- /dev/null +++ b/lib/libc/rpc/svc_udp.c @@ -0,0 +1,482 @@ +/* + * 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 1.3 1995/05/30 05:41:39 rgrimes 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 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; + static int cache_get(); + + 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 < (int)(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; + static void cache_set(); + + 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 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 +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); +} + |