/* $OpenBSD: rpc.c,v 1.15 2015/08/15 19:42:56 miod Exp $ */ /* $NetBSD: rpc.c,v 1.16 1996/10/13 02:29:06 christos Exp $ */ /* * Copyright (c) 1992 Regents of the University of California. * All rights reserved. * * This software was developed by the Computer Systems Engineering group * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and * contributed to Berkeley. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Lawrence Berkeley Laboratory and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) */ /* * RPC functions used by NFS and bootparams. * Note that bootparams requires the ability to find out the * address of the server from which its response has come. * This is supported by keeping the IP/UDP headers in the * buffer space provided by the caller. (See rpc_fromaddr) */ #include #include #include #include #include "stand.h" #include "net.h" #include "netif.h" #include "rpc.h" struct auth_info { int32_t authtype; /* auth type */ u_int32_t authlen; /* auth length */ }; struct auth_unix { int32_t ua_time; int32_t ua_hostname; /* null */ int32_t ua_uid; int32_t ua_gid; int32_t ua_gidlist; /* null */ }; struct rpc_call { u_int32_t rp_xid; /* request transaction id */ int32_t rp_direction; /* call direction (0) */ u_int32_t rp_rpcvers; /* rpc version (2) */ u_int32_t rp_prog; /* program */ u_int32_t rp_vers; /* version */ u_int32_t rp_proc; /* procedure */ }; struct rpc_reply { u_int32_t rp_xid; /* request transaction id */ int32_t rp_direction; /* call direction (1) */ int32_t rp_astatus; /* accept status (0: accepted) */ union { u_int32_t rpu_errno; struct { struct auth_info rok_auth; u_int32_t rok_status; } rpu_rok; } rp_u; }; /* Local forwards */ static ssize_t recvrpc(struct iodesc *, void *, size_t, time_t); static int rpc_getport(struct iodesc *, u_int32_t, u_int32_t); int rpc_xid; int rpc_port = 0x400; /* predecrement */ /* * Make a rpc call; return length of answer * Note: Caller must leave room for headers. */ ssize_t rpc_call(struct iodesc *d, u_int32_t prog, u_int32_t vers, u_int32_t proc, void *sdata, size_t slen, void *rdata, size_t rlen) { ssize_t cc; struct auth_info *auth; struct rpc_call *call; struct rpc_reply *reply; char *send_head, *send_tail; char *recv_head, *recv_tail; u_int32_t x; int port; /* host order */ #ifdef RPC_DEBUG if (debug) printf("rpc_call: prog=0x%x vers=%d proc=%d\n", prog, vers, proc); #endif port = rpc_getport(d, prog, vers); if (port == -1) return (-1); d->destport = htons(port); /* * Prepend authorization stuff and headers. * Note, must prepend things in reverse order. */ send_head = sdata; send_tail = (char *)sdata + slen; /* Auth verifier is always auth_null */ send_head -= sizeof(*auth); auth = (struct auth_info *)send_head; auth->authtype = htonl(RPCAUTH_NULL); auth->authlen = 0; #if 1 /* Auth credentials: always auth unix (as root) */ send_head -= sizeof(struct auth_unix); bzero(send_head, sizeof(struct auth_unix)); send_head -= sizeof(*auth); auth = (struct auth_info *)send_head; auth->authtype = htonl(RPCAUTH_UNIX); auth->authlen = htonl(sizeof(struct auth_unix)); #else /* Auth credentials: always auth_null (XXX OK?) */ send_head -= sizeof(*auth); auth = send_head; auth->authtype = htonl(RPCAUTH_NULL); auth->authlen = 0; #endif /* RPC call structure. */ send_head -= sizeof(*call); call = (struct rpc_call *)send_head; rpc_xid++; call->rp_xid = htonl(rpc_xid); call->rp_direction = htonl(RPC_CALL); call->rp_rpcvers = htonl(RPC_VER2); call->rp_prog = htonl(prog); call->rp_vers = htonl(vers); call->rp_proc = htonl(proc); /* Make room for the rpc_reply header. */ recv_head = rdata; recv_tail = (char *)rdata + rlen; recv_head -= sizeof(*reply); cc = sendrecv(d, sendudp, send_head, send_tail - send_head, recvrpc, recv_head, recv_tail - recv_head); #ifdef RPC_DEBUG if (debug) printf("callrpc: cc=%d rlen=%d\n", cc, rlen); #endif if (cc <= -1) return (-1); if ((size_t)cc <= sizeof(*reply)) { errno = EBADRPC; return (-1); } recv_tail = recv_head + cc; /* * Check the RPC reply status. * The xid, dir, astatus were already checked. */ reply = (struct rpc_reply *)recv_head; auth = &reply->rp_u.rpu_rok.rok_auth; x = ntohl(auth->authlen); if (x != 0) { #ifdef RPC_DEBUG if (debug) printf("callrpc: reply auth != NULL\n"); #endif errno = EBADRPC; return(-1); } x = ntohl(reply->rp_u.rpu_rok.rok_status); if (x != 0) { printf("callrpc: error = %d\n", x); errno = EBADRPC; return(-1); } recv_head += sizeof(*reply); return (ssize_t)(recv_tail - recv_head); } /* * Returns true if packet is the one we're waiting for. * This just checks the XID, direction, acceptance. * Remaining checks are done by callrpc */ static ssize_t recvrpc(struct iodesc *d, void *pkt, size_t len, time_t tleft) { struct rpc_reply *reply; ssize_t n; int x; errno = 0; #ifdef RPC_DEBUG if (debug) printf("recvrpc: called len=%d\n", len); #endif n = readudp(d, pkt, len, tleft); if (n <= (4 * 4)) return -1; reply = (struct rpc_reply *)pkt; x = ntohl(reply->rp_xid); if (x != rpc_xid) { #ifdef RPC_DEBUG if (debug) printf("recvrpc: rp_xid %d != xid %d\n", x, rpc_xid); #endif return -1; } x = ntohl(reply->rp_direction); if (x != RPC_REPLY) { #ifdef RPC_DEBUG if (debug) printf("recvrpc: rp_direction %d != REPLY\n", x); #endif return -1; } x = ntohl(reply->rp_astatus); if (x != RPC_MSGACCEPTED) { errno = ntohl(reply->rp_u.rpu_errno); printf("recvrpc: reject, astat=%d, errno=%d\n", x, errno); return -1; } /* Return data count (thus indicating success) */ return (n); } /* * Given a pointer to a reply just received, * dig out the IP address/port from the headers. */ void rpc_fromaddr(void *pkt, struct in_addr *addr, u_short *port) { struct hackhdr { /* Tail of IP header: just IP addresses */ u_int32_t ip_src; u_int32_t ip_dst; /* UDP header: */ u_int16_t uh_sport; /* source port */ u_int16_t uh_dport; /* destination port */ int16_t uh_ulen; /* udp length */ u_int16_t uh_sum; /* udp checksum */ /* RPC reply header: */ struct rpc_reply rpc; } *hhdr; hhdr = ((struct hackhdr *)pkt) - 1; addr->s_addr = hhdr->ip_src; *port = hhdr->uh_sport; } /* * RPC Portmapper cache */ #define PMAP_NUM 8 /* need at most 5 pmap entries */ int rpc_pmap_num; struct pmap_list { struct in_addr addr; /* server, net order */ u_int prog; /* host order */ u_int vers; /* host order */ int port; /* host order */ } rpc_pmap_list[PMAP_NUM]; /* return port number in host order, or -1 */ int rpc_pmap_getcache(struct in_addr addr, u_int prog, u_int vers) { struct pmap_list *pl; for (pl = rpc_pmap_list; pl < &rpc_pmap_list[rpc_pmap_num]; pl++) { if (pl->addr.s_addr == addr.s_addr && pl->prog == prog && pl->vers == vers) return (pl->port); } return (-1); } void rpc_pmap_putcache(struct in_addr addr, u_int prog, u_int vers, int port) { struct pmap_list *pl; /* Don't overflow cache... */ if (rpc_pmap_num >= PMAP_NUM) { /* ... just re-use the last entry. */ rpc_pmap_num = PMAP_NUM - 1; #ifdef RPC_DEBUG printf("rpc_pmap_putcache: cache overflow\n"); #endif } pl = &rpc_pmap_list[rpc_pmap_num]; rpc_pmap_num++; /* Cache answer */ pl->addr = addr; pl->prog = prog; pl->vers = vers; pl->port = port; } /* * Request a port number from the port mapper. * Returns the port in host order. */ int rpc_getport(struct iodesc *d, u_int32_t prog, u_int32_t vers) { struct args { u_int32_t prog; /* call program */ u_int32_t vers; /* call version */ u_int32_t proto; /* call protocol */ u_int32_t port; /* call port (unused) */ } *args; struct res { u_int32_t port; } *res; struct { u_int32_t h[RPC_HEADER_WORDS]; struct args d; } sdata; struct { u_int32_t h[RPC_HEADER_WORDS]; struct res d; u_int32_t pad; } rdata; ssize_t cc; int port; #ifdef RPC_DEBUG if (debug) printf("getport: prog=0x%x vers=%d\n", prog, vers); #endif /* This one is fixed forever. */ if (prog == PMAPPROG) return (PMAPPORT); /* Try for cached answer first */ port = rpc_pmap_getcache(d->destip, prog, vers); if (port != -1) return (port); args = &sdata.d; args->prog = htonl(prog); args->vers = htonl(vers); args->proto = htonl(IPPROTO_UDP); args->port = 0; res = &rdata.d; cc = rpc_call(d, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT, args, sizeof(*args), res, sizeof(*res)); if (cc < 0 || (size_t)cc < sizeof(*res)) { printf("getport: %s", strerror(errno)); errno = EBADRPC; return (-1); } port = (int)ntohl(res->port); rpc_pmap_putcache(d->destip, prog, vers, port); return (port); }