Introduce helper functions that can construct and send raw
NSMPROC_NOTIFY, NLM downcalls, and portmapper calls over a datagram
socket, and receive and parse their replies. Support for IPv6 and
RPCB_GETADDR is featured. This code (and the IPv6 support it
introduces) can now be shared by statd and sm-notify, eliminating
code and bug duplication.
This implementation is based on what's in utils/statd/rmtcall.c now,
but is wrapped up in a nice API and includes extra error checking.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
support/include/nsm.h | 25 ++
support/nsm/Makefile.am | 2
support/nsm/rpc.c | 505 +++++++++++++++++++++++++++++++++++++
++++++++++
3 files changed, 531 insertions(+), 1 deletions(-)
create mode 100644 support/nsm/rpc.c
diff --git a/support/include/nsm.h b/support/include/nsm.h
index 594f0d9..96b23f2 100644
--- a/support/include/nsm.h
+++ b/support/include/nsm.h
@@ -59,4 +59,29 @@ extern int nsm_insert_monitored_host(const char
*hostname,
extern void nsm_delete_monitored_host(const char *hostname);
extern void nsm_delete_notified_host(const char *hostname);
+/* rpc.c */
+
+#define NSM_MAXMSGSIZE (2048 / sizeof(uint32_t))
+
+extern uint32_t nsm_xmit_getport(const int sock,
+ const struct sockaddr_in *sin,
+ const unsigned long program,
+ const unsigned long version);
+extern uint32_t nsm_xmit_getaddr(const int sock,
+ const struct sockaddr_in6 *sin6,
+ const rpcprog_t program, const rpcvers_t version);
+extern uint32_t nsm_xmit_rpcbind(const int sock, const struct
sockaddr *sap,
+ const rpcprog_t program, const rpcvers_t version);
+extern uint32_t nsm_xmit_notify(const int sock, const struct
sockaddr *sap,
+ const socklen_t salen, const rpcprog_t program,
+ const char *mon_name, const int state);
+extern uint32_t nsm_xmit_nlmcall(const int sock, const struct
sockaddr *sap,
+ const socklen_t salen, const struct mon *mon,
+ const int state);
+extern uint32_t nsm_parse_reply(XDR *xdrs);
+extern unsigned long
+ nsm_recv_getport(XDR *xdrs);
+extern uint16_t nsm_recv_getaddr(XDR *xdrs);
+extern uint16_t nsm_recv_rpcbind(const int family, XDR *xdrs);
+
#endif /* !_NFS_UTILS_SUPPORT_NSM_H */
diff --git a/support/nsm/Makefile.am b/support/nsm/Makefile.am
index e359a43..2038e68 100644
--- a/support/nsm/Makefile.am
+++ b/support/nsm/Makefile.am
@@ -10,7 +10,7 @@ GENFILES = $(GENFILES_CLNT) $(GENFILES_SVC) $
(GENFILES_XDR) $(GENFILES_H)
EXTRA_DIST = sm_inter.x
noinst_LIBRARIES = libnsm.a
-libnsm_a_SOURCES = $(GENFILES) file.c
+libnsm_a_SOURCES = $(GENFILES) file.c rpc.c
BUILT_SOURCES = $(GENFILES)
diff --git a/support/nsm/rpc.c b/support/nsm/rpc.c
new file mode 100644
index 0000000..a9d3a62
--- /dev/null
+++ b/support/nsm/rpc.c
@@ -0,0 +1,505 @@
+/*
+ * Copyright 2009 Oracle. All rights reserved.
+ *
+ * This file is part of nfs-utils.
+ *
+ * nfs-utils is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as
published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * nfs-utils is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with nfs-utils. If not, see <http://www.gnu.org/licenses/
>.
+ */
+
+/*
+ * NSM for Linux.
+ *
+ * Instead of using ONC or TI RPC library calls, statd constructs
+ * RPC calls directly in socket buffers. This allows a single
+ * socket to be concurrently shared among several different RPC
+ * programs and versions using a simple RPC request dispatcher.
+ *
+ * This file contains the details of RPC header and call
+ * construction and reply parsing, and a method for creating a
+ * socket for use with these functions.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <time.h>
+#include <netdb.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <net/if.h>
+#include <arpa/inet.h>
+
+#include <rpc/rpc.h>
+#include <rpc/pmap_prot.h>
+#include <rpc/pmap_rmt.h>
+
+#ifdef HAVE_LIBTIRPC
+#include <netconfig.h>
+#include <rpc/rpcb_prot.h>
+#endif /* HAVE_LIBTIRPC */
+
+#include "xlog.h"
+#include "nfsrpc.h"
+#include "nsm.h"
+#include "sm_inter.h"
+
+/*
+ * Returns a fresh XID appropriate for RPC over UDP -- never zero.
+ */
+static uint32_t
+nsm_next_xid(void)
+{
+ static uint32_t nsm_xid = 0;
+ struct timeval now;
+
+ if (nsm_xid == 0) {
+ (void)gettimeofday(&now, NULL);
+ nsm_xid = getpid() ^ now.tv_sec ^ now.tv_usec;
+ }
+
+ return nsm_xid++;
+}
+
+/*
+ * Select a fresh XID and construct an RPC header in @mesg.
+ * Always use AUTH_NULL credentials and verifiers.
+ *
+ * Returns the new XID.
+ */
+static uint32_t
+nsm_init_rpc_header(const rpcprog_t program, const rpcvers_t
version,
+ const rpcproc_t procedure, struct rpc_msg *mesg)
+{
+ struct call_body *cb = &mesg->rm_call;
+
+ mesg->rm_xid = nsm_next_xid();
+ mesg->rm_direction = CALL;
+
+ cb->cb_rpcvers = RPC_MSG_VERSION;
+ cb->cb_prog = program;
+ cb->cb_vers = version;
+ cb->cb_proc = procedure;
+
+ cb->cb_cred.oa_flavor = AUTH_NULL;
+ cb->cb_cred.oa_base = (caddr_t) NULL;
+ cb->cb_cred.oa_length = 0;
+ cb->cb_verf.oa_flavor = AUTH_NULL;
+ cb->cb_verf.oa_base = (caddr_t) NULL;
+ cb->cb_verf.oa_length = 0;
+
+ return mesg->rm_xid;
+}
+
+/*
+ * Send a completed RPC call on a socket.
+ *
+ * Returns 1 if all the bytes were sent successfully; otherwise
+ * zero if any error occurred.
+ */
+static int
+nsm_rpc_sendto(const int sock, const struct sockaddr *sap,
+ const socklen_t salen, XDR *xdrs, void *buf)
+{
+ const unsigned int len = xdr_getpos(xdrs);
+ ssize_t err;
+
+ err = sendto(sock, buf, len, 0, sap, salen);
+ if ((err < 0) || ((size_t)err != len)) {
+ xlog(L_ERROR, "%s: sendto failed: %m", __func__);
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * nsm_xmit_getport - post a PMAP_GETPORT call on a socket
descriptor
+ * @sock: datagram socket descriptor
+ * @sin: pointer to AF_INET socket address of server
+ * @program: RPC program number to query
+ * @version: RPC version number to query
+ *
+ * Send a PMAP_GETPORT call to the portmap daemon at @sin using
+ * socket descriptor @sock. This request queries the RPC program
+ * [program, version, IPPROTO_UDP].
+ *
+ * NB: PMAP_GETPORT works only for IPv4 hosts. This implementation
+ * works only over UDP, and queries only UDP registrations.
+ *
+ * Returns the XID of the call, or zero if an error occurred.
+ */
+uint32_t
+nsm_xmit_getport(const int sock, const struct sockaddr_in *sin,
+ const unsigned long program,
+ const unsigned long version)
+{
+ struct pmap parms = {
+ .pm_prog = program,
+ .pm_vers = version,
+ .pm_prot = IPPROTO_UDP,
+ .pm_port = 0,
+ };
+ unsigned int msgbuf[NSM_MAXMSGSIZE];
+ struct rpc_msg mesg;
+ uint32_t xid;
+ int err = 0;
+ XDR xdr;
+
+ xlog(D_CALL, "Sending PMAP_GETPORT for %u, %u, udp", program,
version);
+
+ xid = nsm_init_rpc_header(PMAPPROG, PMAPVERS,
+ (rpcproc_t)PMAPPROC_GETPORT, &mesg);
+
+ xdrmem_create(&xdr, (caddr_t)msgbuf, sizeof(msgbuf), XDR_ENCODE);
+
+ if (xdr_callmsg(&xdr, &mesg) && xdr_pmap(&xdr, &parms)) {
+ struct sockaddr_in addr = *sin;
+
+ addr.sin_port = htons((uint16_t)PMAPPORT);
+ err = nsm_rpc_sendto(sock, (struct sockaddr *)&addr,
+ (socklen_t)sizeof(addr), &xdr, msgbuf);
+ } else
+ xlog(L_ERROR, "%s: can't encode PMAP_GETPORT call", __func__);
+
+ xdr_destroy(&xdr);
+
+ return err? xid : 0;
+}
+
+/**
+ * nsm_xmit_getaddr - post an RPCB_GETADDR call on a socket
descriptor
+ * @sock: datagram socket descriptor
+ * @sin: pointer to AF_INET6 socket address of server
+ * @program: RPC program number to query
+ * @version: RPC version number to query
+ *
+ * Send an RPCB_GETADDR call to the rpcbind daemon at @sap using
+ * socket descriptor @sock. This request queries the RPC program
+ * [program, version, "udp6"].
+ *
+ * NB: RPCB_GETADDR works for both IPv4 and IPv6 hosts. This
+ * implementation works only over UDP and AF_INET6, and queries
+ * only "udp6" registrations.
+ *
+ * Returns the XID of the call, or zero if an error occurred.
+ */
+#ifdef HAVE_LIBTIRPC
+uint32_t
+nsm_xmit_getaddr(const int sock, const struct sockaddr_in6 *sin6,
+ const rpcprog_t program, const rpcvers_t version)
+{
+ struct rpcb parms = {
+ .r_prog = program,
+ .r_vers = version,
+ .r_netid = "udp6",
+ .r_owner = "",
+ };
+ unsigned int msgbuf[NSM_MAXMSGSIZE];
+ struct rpc_msg mesg;
+ uint32_t xid;
+ int err = 0;
+ XDR xdr;
+
+ xlog(D_CALL, "Sending RPCB_GETADDR for %u, %u, udp6", program,
version);
+
+ xid = nsm_init_rpc_header(RPCBPROG, RPCBVERS,
+ (rpcproc_t)RPCBPROC_GETADDR, &mesg);
+
+ parms.r_addr = nfs_sockaddr2universal((struct sockaddr *)sin6);
+ if (parms.r_addr == NULL) {
+ xlog(L_ERROR, "%s: can't encode socket address", __func__);
+ return 0;
+ }
+
+ xdrmem_create(&xdr, (caddr_t)msgbuf, sizeof(msgbuf), XDR_ENCODE);
+
+ if (xdr_callmsg(&xdr, &mesg) && xdr_rpcb(&xdr, &parms)) {
+ struct sockaddr_in6 addr = *sin6;
+
+ addr.sin6_port = htons((uint16_t)PMAPPORT);
+ err = nsm_rpc_sendto(sock, (struct sockaddr *)&addr,
+ (socklen_t)sizeof(addr), &xdr, msgbuf);
+ } else
+ xlog(L_ERROR, "%s: can't encode RPCB_GETADDR call", __func__);
+
+ xdr_destroy(&xdr);
+ free(parms.r_addr);
+
+ return err? xid : 0;
+}
+#else /* !HAVE_LIBTIRPC */
+uint32_t
+nsm_xmit_getaddr(const int sock __attribute__((unused)),
+ const struct sockaddr_in6 *sin6 __attribute__((unused)),
+ const rpcprog_t program __attribute__((unused)),
+ const rpcvers_t version __attribute__((unused)))
+{
+ return 0;
+}
+#endif /* !HAVE_LIBTIRPC */
+
+/**
+ * nsm_xmit_rpcbind - post an rpcbind request
+ * @sock: datagram socket descriptor
+ * @sap: pointer to socket address of server
+ * @program: RPC program number to query
+ * @version: RPC version number to query
+ *
+ * Send an rpcbind query to the rpcbind daemon at @sap using
+ * socket descriptor @sock.
+ *
+ * NB: This implementation works only over UDP, but can query IPv4
or IPv6
+ * hosts. It queries only UDP registrations.
+ *
+ * Returns the XID of the call, or zero if an error occurred.
+ */
+uint32_t
+nsm_xmit_rpcbind(const int sock, const struct sockaddr *sap,
+ const rpcprog_t program, const rpcvers_t version)
+{
+ switch (sap->sa_family) {
+ case AF_INET:
+ return nsm_xmit_getport(sock, (const struct sockaddr_in *)sap,
+ program, version);
+ case AF_INET6:
+ return nsm_xmit_getaddr(sock, (const struct sockaddr_in6 *)sap,
+ program, version);
+ }
+ return 0;
+}
+
+/**
+ * nsm_xmit_notify - post an NSMPROC_NOTIFY call on a socket
descriptor
+ * @sock: datagram socket descriptor
+ * @sap: pointer to socket address of peer to notify (port already
filled in)
+ * @salen: length of socket address
+ * @program: RPC program number to use
+ * @mon_name: mon_name of local peer (ie the rebooting system)
+ * @state: state of local peer
+ *
+ * Send an NSMPROC_NOTIFY call to the peer at @sap using socket
descriptor @sock.
+ * This request notifies the peer that we have rebooted.
+ *
+ * NB: This implementation works only over UDP, but supports both
AF_INET
+ * and AF_INET6.
+ *
+ * Returns the XID of the call, or zero if an error occurred.
+ */
+uint32_t
+nsm_xmit_notify(const int sock, const struct sockaddr *sap,
+ const socklen_t salen, const rpcprog_t program,
+ const char *mon_name, const int state)
+{
+ struct stat_chge state_change = {
+ .mon_name = strdup(mon_name),
+ .state = state,
+ };
+ unsigned int msgbuf[NSM_MAXMSGSIZE];
+ struct rpc_msg mesg;
+ uint32_t xid;
+ int err = 0;
+ XDR xdr;
+
+ if (state_change.mon_name == NULL) {
+ xlog(L_ERROR, "%s: no memory", __func__);
+ return 0;
+ }
+
+ xlog(D_CALL, "Sending SM_NOTIFY for %s", mon_name);
+
+ xid = nsm_init_rpc_header(program, SM_VERS, SM_NOTIFY, &mesg);
+
+ xdrmem_create(&xdr, (caddr_t)msgbuf, sizeof(msgbuf), XDR_ENCODE);
+
+ if (xdr_callmsg(&xdr, &mesg) && xdr_stat_chge(&xdr,
&state_change)) {
+ err = nsm_rpc_sendto(sock, sap, salen, &xdr, msgbuf);
+ } else
+ xlog(L_ERROR, "%s: can't encode NSMPROC_NOTIFY call",
+ __func__);
+
+ xdr_destroy(&xdr);
+ free(state_change.mon_name);
+
+ return err? xid : 0;
+}
+
+/**
+ * nsm_xmit_nlmcall - post an unnamed call to local NLM on a
socket descriptor
+ * @sock: datagram socket descriptor
+ * @sap: address/port of NLM service to contact
+ * @salen: size of @sap
+ * @mon: callback data defining RPC call to make
+ * @state: state of rebooting host
+ *
+ * Send an unnamed call (previously requested via NSMPROC_MON) to
the
+ * specified local UDP-based RPC service using socket descriptor
@sock.
+ *
+ * NB: This implementation works only over UDP, but supports both
AF_INET
+ * and AF_INET6.
+ *
+ * Returns the XID of the call, or zero if an error occurred.
+ */
+uint32_t
+nsm_xmit_nlmcall(const int sock, const struct sockaddr *sap,
+ const socklen_t salen, const struct mon *mon,
+ const int state)
+{
+ struct status new_status = {
+ .mon_name = mon->mon_id.mon_name,
+ .state = state,
+ };
+ const struct my_id *id = &mon->mon_id.my_id;
+ unsigned int msgbuf[NSM_MAXMSGSIZE];
+ struct rpc_msg mesg;
+ uint32_t xid;
+ int err = 0;
+ XDR xdr;
+
+ xlog(D_CALL, "Sending NLM downcall for %s", mon->mon_id.mon_name);
+
+ xid = nsm_init_rpc_header(id->my_prog, id->my_vers, id->my_proc,
&mesg);
+
+ memcpy(&new_status.priv, &mon->priv, sizeof(new_status.priv));
+ xdrmem_create(&xdr, (caddr_t)msgbuf, sizeof(msgbuf), XDR_ENCODE);
+
+ if (xdr_callmsg(&xdr, &mesg) && xdr_status(&xdr, &new_status))
+ err = nsm_rpc_sendto(sock, sap, salen, &xdr, msgbuf);
+ else
+ xlog(L_ERROR, "%s: can't encode NLM downcall", __func__);
+
+ xdr_destroy(&xdr);
+
+ return err? xid : 0;
+}
+
+/**
+ * nsm_parse_reply - parse and validate the header in an RPC reply
+ * @xdrs: pointer to XDR
+ *
+ * Returns the XID of the reply, or zero if an error occurred.
+ */
+uint32_t
+nsm_parse_reply(XDR *xdrs)
+{
+ struct rpc_msg mesg = {
+ .rm_reply.rp_acpt.ar_results.proc = (xdrproc_t)xdr_void,
+ };
+
+ if (!xdr_replymsg(xdrs, &mesg)) {
+ xlog(L_ERROR, "%s: can't decode RPC reply", __func__);
+ return 0;
+ }
+
+ if (mesg.rm_reply.rp_stat != 0) {
+ xlog(L_ERROR, "%s: [0x%x] RPC status %d",
+ __func__, mesg.rm_xid, mesg.rm_reply.rp_stat);
+ return 0;
+ }
+
+ if (mesg.rm_reply.rp_acpt.ar_stat != 0) {
+ xlog(L_ERROR, "%s: [0x%x] RPC accept status %d",
+ __func__, mesg.rm_xid, mesg.rm_reply.rp_acpt.ar_stat);
+ return 0;
+ }
+
+ return mesg.rm_xid;
+}
+
+/**
+ * nsm_recv_getport - parse PMAP_GETPORT reply
+ * @xdrs: pointer to XDR
+ *
+ * Returns the port number from the RPC reply, or zero
+ * if an error occurred.
+ */
+unsigned long
+nsm_recv_getport(XDR *xdrs)
+{
+ unsigned long port = 0;
+
+ if (!xdr_u_long(xdrs, &port))
+ xlog(L_ERROR, "%s: can't decode pmap reply",
+ __func__);
+ if (port > UINT16_MAX) {
+ xlog(L_ERROR, "%s: bad port number",
+ __func__);
+ port = 0;
+ }
+
+ xlog(D_CALL, "Received PMAP_GETPORT result: %lu", port);
+ return port;
+}
+
+/**
+ * nsm_recv_getaddr - parse RPCB_GETADDR reply
+ * @xdrs: pointer to XDR
+ *
+ * Returns the port number from the RPC reply, or zero
+ * if an error occurred.
+ */
+uint16_t
+nsm_recv_getaddr(XDR *xdrs)
+{
+ int port;
+ char *uaddr = NULL;
+
+ if (!xdr_wrapstring(xdrs, &uaddr))
+ xlog(L_ERROR, "%s: can't decode rpcb reply",
+ __func__);
+
+ if ((uaddr == NULL) || (uaddr[0] == '\0')) {
+ xlog(D_CALL, "Received RPCB_GETADDR result: "
+ "program not registered");
+ return 0;
+ }
+
+ port = nfs_universal2port(uaddr);
+
+ xdr_free((xdrproc_t)xdr_wrapstring, (char *)&uaddr);
+
+ if (port < 0 || port > UINT16_MAX) {
+ xlog(L_ERROR, "%s: bad port number",
+ __func__);
+ return 0;
+ }
+
+ xlog(D_CALL, "Received RPCB_GETADDR result: %d", port);
+ return port;
+}
+
+/**
+ * nsm_recv_rpcbind - parse rpcbind reply
+ * @af: address family of reply
+ * @xdrs: pointer to XDR
+ *
+ * Returns the port number from the RPC reply, or zero
+ * if an error occurred.
+ */
+uint16_t
+nsm_recv_rpcbind(const int family, XDR *xdrs)
+{
+ switch (family) {
+ case AF_INET:
+ return nsm_recv_getport(xdrs);
+ case AF_INET6:
+ return nsm_recv_getaddr(xdrs);
+ }
+ return 0;
+}
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