/* $OpenBSD: krpc_subr.c,v 1.31 2017/08/10 19:20:43 mpi Exp $ */ /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */ /* * Copyright (c) 1995 Gordon Ross, Adam Glass * 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. * * partially based on: * libnetboot/rpc.c * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Kernel support for Sun RPC * * Used currently for bootstrapping in nfs diskless configurations. */ /* * Generic RPC headers */ struct auth_info { u_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 auth_info rpc_auth; struct auth_unix rpc_unix; struct auth_info rpc_verf; }; 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; }; #define rp_errno rp_u.rpu_errno #define rp_auth rp_u.rpu_rok.rok_auth #define rp_status rp_u.rpu_rok.rok_status #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */ u_int32_t krpc_get_xid(void); /* * Return an unpredictable XID. */ u_int32_t krpc_get_xid(void) { static struct idgen32_ctx krpc_xid_ctx; static int called = 0; if (!called) { called = 1; idgen32_init(&krpc_xid_ctx); } return idgen32(&krpc_xid_ctx); } /* * What is the longest we will wait before re-sending a request? * Note this is also the frequency of "RPC timeout" messages. * The re-send loop count sup linearly to this maximum, so the * first complaint will happen after (1+2+3+4+5)=15 seconds. */ #define MAX_RESEND_DELAY 5 /* seconds */ /* * Call portmap to lookup a port number for a particular rpc program * Returns non-zero error on failure. */ int krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp) { struct sdata { 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) */ } *sdata; struct rdata { u_int16_t pad; u_int16_t port; } *rdata; struct mbuf *m; int error; /* The portmapper port is fixed. */ if (prog == PMAPPROG) { *portp = htons(PMAPPORT); return 0; } m = m_get(M_WAIT, MT_DATA); sdata = mtod(m, struct sdata *); m->m_len = sizeof(*sdata); /* Do the RPC to get it. */ sdata->prog = txdr_unsigned(prog); sdata->vers = txdr_unsigned(vers); sdata->proto = txdr_unsigned(IPPROTO_UDP); sdata->port = 0; sin->sin_port = htons(PMAPPORT); error = krpc_call(sin, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT, &m, NULL, -1); if (error) return error; if (m->m_len < sizeof(*rdata)) { m = m_pullup(m, sizeof(*rdata)); if (m == NULL) return ENOBUFS; } rdata = mtod(m, struct rdata *); *portp = rdata->port; m_freem(m); return 0; } /* * Do a remote procedure call (RPC) and wait for its reply. * If from_p is non-null, then we are doing broadcast, and * the address from whence the response came is saved there. * data: input/output * from_p: output */ int krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func, struct mbuf **data, struct mbuf **from_p, int retries) { struct socket *so; struct sockaddr_in *sin; struct mbuf *m, *nam, *mhead, *from, *mopt; struct rpc_call *call; struct rpc_reply *reply; struct uio auio; int s, error, rcvflg, timo, secs, len; static u_int32_t xid = 0; char addr[INET_ADDRSTRLEN]; int *ip; struct timeval tv; /* * Validate address family. * Sorry, this is INET specific... */ if (sa->sin_family != AF_INET) return (EAFNOSUPPORT); /* Free at end if not null. */ nam = mhead = NULL; from = NULL; /* * Create socket and set its receive timeout. */ if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0))) goto out; m = m_get(M_WAIT, MT_SOOPTS); tv.tv_sec = 1; tv.tv_usec = 0; memcpy(mtod(m, struct timeval *), &tv, sizeof tv); m->m_len = sizeof(tv); s = solock(so); error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m); sounlock(s); if (error) goto out; /* * Enable broadcast if necessary. */ if (from_p) { int32_t *on; m = m_get(M_WAIT, MT_SOOPTS); on = mtod(m, int32_t *); m->m_len = sizeof(*on); *on = 1; s = solock(so); error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m); sounlock(s); if (error) goto out; } /* * Bind the local endpoint to a reserved port, * because some NFS servers refuse requests from * non-reserved (non-privileged) ports. */ MGET(mopt, M_WAIT, MT_SOOPTS); mopt->m_len = sizeof(int); ip = mtod(mopt, int *); *ip = IP_PORTRANGE_LOW; s = solock(so); error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt); sounlock(s); if (error) goto out; MGET(m, M_WAIT, MT_SONAME); sin = mtod(m, struct sockaddr_in *); memset(sin, 0, sizeof(*sin)); sin->sin_len = m->m_len = sizeof(struct sockaddr_in); sin->sin_family = AF_INET; sin->sin_addr.s_addr = INADDR_ANY; sin->sin_port = htons(0); s = solock(so); error = sobind(so, m, &proc0); sounlock(s); m_freem(m); if (error) { printf("bind failed\n"); goto out; } MGET(mopt, M_WAIT, MT_SOOPTS); mopt->m_len = sizeof(int); ip = mtod(mopt, int *); *ip = IP_PORTRANGE_DEFAULT; s = solock(so); error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt); sounlock(s); if (error) goto out; /* * Setup socket address for the server. */ nam = m_get(M_WAIT, MT_SONAME); sin = mtod(nam, struct sockaddr_in *); bcopy(sa, sin, (nam->m_len = sa->sin_len)); /* * Prepend RPC message header. */ mhead = m_gethdr(M_WAIT, MT_DATA); mhead->m_next = *data; call = mtod(mhead, struct rpc_call *); mhead->m_len = sizeof(*call); memset(call, 0, sizeof(*call)); /* rpc_call part */ xid = krpc_get_xid(); call->rp_xid = txdr_unsigned(xid); /* call->rp_direction = 0; */ call->rp_rpcvers = txdr_unsigned(2); call->rp_prog = txdr_unsigned(prog); call->rp_vers = txdr_unsigned(vers); call->rp_proc = txdr_unsigned(func); /* rpc_auth part (auth_unix as root) */ call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX); call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix)); /* rpc_verf part (auth_null) */ call->rpc_verf.authtype = 0; call->rpc_verf.authlen = 0; /* * Setup packet header */ len = 0; m = mhead; while (m) { len += m->m_len; m = m->m_next; } mhead->m_pkthdr.len = len; mhead->m_pkthdr.ph_ifidx = 0; /* * Send it, repeatedly, until a reply is received, * but delay each re-send by an increasing amount. * If the delay hits the maximum, start complaining. */ for (timo = 0; retries; retries--) { /* Send RPC request (or re-send). */ m = m_copym(mhead, 0, M_COPYALL, M_WAIT); if (m == NULL) { error = ENOBUFS; goto out; } error = sosend(so, nam, NULL, m, NULL, 0); if (error) { printf("krpc_call: sosend: %d\n", error); goto out; } m = NULL; /* Determine new timeout. */ if (timo < MAX_RESEND_DELAY) timo++; else printf("RPC timeout for server %s (0x%x) prog %u\n", inet_ntop(AF_INET, &sin->sin_addr, addr, sizeof(addr)), ntohl(sin->sin_addr.s_addr), prog); /* * Wait for up to timo seconds for a reply. * The socket receive timeout was set to 1 second. */ secs = timo; while (secs > 0) { m_freem(from); from = NULL; m_freem(m); m = NULL; auio.uio_resid = len = 1<<16; auio.uio_procp = NULL; rcvflg = 0; error = soreceive(so, &from, &auio, &m, NULL, &rcvflg, 0); if (error == EWOULDBLOCK) { secs--; continue; } if (error) goto out; len -= auio.uio_resid; /* Does the reply contain at least a header? */ if (len < MIN_REPLY_HDR) continue; if (m->m_len < MIN_REPLY_HDR) continue; reply = mtod(m, struct rpc_reply *); /* Is it the right reply? */ if (reply->rp_direction != txdr_unsigned(RPC_REPLY)) continue; if (reply->rp_xid != txdr_unsigned(xid)) continue; /* Was RPC accepted? (authorization OK) */ if (reply->rp_astatus != 0) { error = fxdr_unsigned(u_int32_t, reply->rp_errno); printf("rpc denied, error=%d\n", error); continue; } /* Did the call succeed? */ if (reply->rp_status != 0) { error = fxdr_unsigned(u_int32_t, reply->rp_status); printf("rpc denied, status=%d\n", error); continue; } goto gotreply; /* break two levels */ } /* while secs */ } /* forever send/receive */ error = ETIMEDOUT; goto out; gotreply: /* * Get RPC reply header into first mbuf, * get its length, then strip it off. */ len = sizeof(*reply); if (m->m_len < len) { m = m_pullup(m, len); if (m == NULL) { error = ENOBUFS; goto out; } } reply = mtod(m, struct rpc_reply *); if (reply->rp_auth.authtype != 0) { len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen); len = (len + 3) & ~3; /* XXX? */ } m_adj(m, len); /* result */ *data = m; if (from_p && error == 0) { *from_p = from; from = NULL; } out: m_freem(nam); m_freem(mhead); m_freem(from); soclose(so); return error; } /* * eXternal Data Representation routines. * (but with non-standard args...) */ /* * String representation for RPC. */ struct xdr_string { u_int32_t len; /* length without null or padding */ char data[4]; /* data (longer, of course) */ /* data is padded to a long-word boundary */ }; struct mbuf * xdr_string_encode(char *str, int len) { struct mbuf *m; struct xdr_string *xs; int dlen; /* padded string length */ int mlen; /* message length */ dlen = (len + 3) & ~3; mlen = dlen + 4; if (mlen > MCLBYTES) /* If too big, we just can't do it. */ return (NULL); m = m_get(M_WAIT, MT_DATA); if (mlen > MLEN) { MCLGET(m, M_WAIT); if ((m->m_flags & M_EXT) == 0) { (void) m_free(m); /* There can be only one. */ return (NULL); } } xs = mtod(m, struct xdr_string *); m->m_len = mlen; xs->len = txdr_unsigned(len); bcopy(str, xs->data, len); return (m); } struct mbuf * xdr_string_decode(struct mbuf *m, char *str, int *len_p) { struct xdr_string *xs; int mlen; /* message length */ int slen; /* string length */ if (m->m_len < 4) { m = m_pullup(m, 4); if (m == NULL) return (NULL); } xs = mtod(m, struct xdr_string *); slen = fxdr_unsigned(u_int32_t, xs->len); mlen = 4 + ((slen + 3) & ~3); if (slen > *len_p) slen = *len_p; if (slen > m->m_pkthdr.len) { m_freem(m); return (NULL); } m_copydata(m, 4, slen, str); m_adj(m, mlen); str[slen] = '\0'; *len_p = slen; return (m); } /* * Inet address in RPC messages * (Note, really four ints, NOT chars. Blech.) */ struct xdr_inaddr { u_int32_t atype; u_int32_t addr[4]; }; struct mbuf * xdr_inaddr_encode(struct in_addr *ia) { struct mbuf *m; struct xdr_inaddr *xi; u_int8_t *cp; u_int32_t *ip; m = m_get(M_WAIT, MT_DATA); xi = mtod(m, struct xdr_inaddr *); m->m_len = sizeof(*xi); xi->atype = txdr_unsigned(1); ip = xi->addr; cp = (u_int8_t *)&ia->s_addr; *ip++ = txdr_unsigned(*cp++); *ip++ = txdr_unsigned(*cp++); *ip++ = txdr_unsigned(*cp++); *ip++ = txdr_unsigned(*cp++); return (m); } struct mbuf * xdr_inaddr_decode(struct mbuf *m, struct in_addr *ia) { struct xdr_inaddr *xi; u_int8_t *cp; u_int32_t *ip; if (m->m_len < sizeof(*xi)) { m = m_pullup(m, sizeof(*xi)); if (m == NULL) return (NULL); } xi = mtod(m, struct xdr_inaddr *); if (xi->atype != txdr_unsigned(1)) { ia->s_addr = INADDR_ANY; goto out; } ip = xi->addr; cp = (u_int8_t *)&ia->s_addr; *cp++ = fxdr_unsigned(u_int8_t, *ip++); *cp++ = fxdr_unsigned(u_int8_t, *ip++); *cp++ = fxdr_unsigned(u_int8_t, *ip++); *cp++ = fxdr_unsigned(u_int8_t, *ip++); out: m_adj(m, sizeof(*xi)); return (m); }