Moving Sun RPC code into libc, part 1. Based on work done by a number of

people, including J.T. Conklin, Theo de Raadt, Paul Richards, and probably
someone else who's going to flame me as soon as they see this message.

1 files changed, 480 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..d7c7bb2
--- /dev/null
+++ b/lib/libc/rpc/svc_udp.c
@@ -0,0 +1,480 @@
+/*
+ * 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 1.1 1993/10/27 05:41:03 paul 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 <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 < 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);
+}
+