usr/src/cmd/fm/fmd/common/fmd_rpc.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24
  25 #include <sys/types.h>
  26 #include <sys/fm/util.h>
  27
  28 #include <netdir.h>
  29 #include <strings.h>
  30 #include <alloca.h>
  31 #include <limits.h>
  32 #include <unistd.h>
  33 #include <ucred.h>
  34 #include <priv.h>
  35
  36 #include <fmd_rpc_api.h>
  37 #include <fmd_rpc_adm.h>
  38 #include <rpc/svc_mt.h>
  39
  40 #include <fmd_subr.h>
  41 #include <fmd_error.h>
  42 #include <fmd_thread.h>
  43 #include <fmd_conf.h>
  44 #include <fmd_api.h>
  45 #include <fmd.h>
  46
  47 /*
  48  * Define range of transient RPC program numbers to use for transient bindings.
  49  * These are defined in the Solaris ONC+ Developer's Guide, Appendix B, but
  50  * are cleverly not defined in any ONC+ standard system header file.
  51  */
  52 #define RPC_TRANS_MIN   0x40000000
  53 #define RPC_TRANS_MAX   0x5fffffff
  54
  55 /*
  56  * We use our own private version of svc_create() which registers our services
  57  * only on loopback transports and enables an option whereby Solaris ucreds
  58  * are associated with each connection, permitting us to check privilege bits.
  59  */
  60 static int
  61 fmd_rpc_svc_create_local(void (*disp)(struct svc_req *, SVCXPRT *),
  62     rpcprog_t prog, rpcvers_t vers, uint_t ssz, uint_t rsz, int force)
  63 {
  64         struct netconfig *ncp;
  65         struct netbuf buf;
  66         SVCXPRT *xprt;
  67         void *hdl;
  68         int fd, n = 0;
  69
  70         char door[PATH_MAX];
  71         time_t tm;
  72
  73         if ((hdl = setnetconfig()) == NULL) {
  74                 fmd_error(EFMD_RPC_REG, "failed to iterate over "
  75                     "netconfig database: %s\n", nc_sperror());
  76                 return (fmd_set_errno(EFMD_RPC_REG));
  77         }
  78
  79         if (force)
  80                 svc_unreg(prog, vers); /* clear stale rpcbind registrations */
  81
  82         buf.buf = alloca(_SS_MAXSIZE);
  83         buf.maxlen = _SS_MAXSIZE;
  84         buf.len = 0;
  85
  86         while ((ncp = getnetconfig(hdl)) != NULL) {
  87                 if (strcmp(ncp->nc_protofmly, NC_LOOPBACK) != 0)
  88                         continue;
  89
  90                 if (!force && rpcb_getaddr(prog, vers, ncp, &buf, HOST_SELF)) {
  91                         (void) endnetconfig(hdl);
  92                         return (fmd_set_errno(EFMD_RPC_BOUND));
  93                 }
  94
  95                 if ((fd = t_open(ncp->nc_device, O_RDWR, NULL)) == -1) {
  96                         fmd_error(EFMD_RPC_REG, "failed to open %s: %s\n",
  97                             ncp->nc_device, t_strerror(t_errno));
  98                         continue;
  99                 }
 100
 101                 svc_fd_negotiate_ucred(fd); /* enable ucred option on xprt */
 102
 103                 if ((xprt = svc_tli_create(fd, ncp, NULL, ssz, rsz)) == NULL) {
 104                         (void) t_close(fd);
 105                         continue;
 106                 }
 107
 108                 if (svc_reg(xprt, prog, vers, disp, ncp) == FALSE) {
 109                         fmd_error(EFMD_RPC_REG, "failed to register "
 110                             "rpc service on %s\n", ncp->nc_netid);
 111                         svc_destroy(xprt);
 112                         continue;
 113                 }
 114
 115                 n++;
 116         }
 117
 118         (void) endnetconfig(hdl);
 119
 120         /*
 121          * If we failed to register services (n == 0) because rpcbind is down,
 122          * then check to see if the RPC door file exists before attempting an
 123          * svc_door_create(), which cleverly destroys any existing door file.
 124          * The RPC APIs have no stable errnos, so we use rpcb_gettime() as a
 125          * hack to determine if rpcbind itself is down.
 126          */
 127         if (!force && n == 0 && rpcb_gettime(HOST_SELF, &tm) == FALSE &&
 128             snprintf(door, sizeof (door), RPC_DOOR_RENDEZVOUS,
 129             prog, vers) > 0 && access(door, F_OK) == 0)
 130                 return (fmd_set_errno(EFMD_RPC_BOUND));
 131
 132         /*
 133          * Attempt to create a door server for the RPC program as well.  Limit
 134          * the maximum request size for the door transport to the receive size.
 135          */
 136         if ((xprt = svc_door_create(disp, prog, vers, ssz)) == NULL) {
 137                 fmd_error(EFMD_RPC_REG, "failed to create door for "
 138                     "rpc service 0x%lx/0x%lx\n", prog, vers);
 139         } else {
 140                 (void) svc_control(xprt, SVCSET_CONNMAXREC, &rsz);
 141                 n++;
 142         }
 143
 144         return (n);
 145 }
 146
 147 static int
 148 fmd_rpc_svc_init(void (*disp)(struct svc_req *, SVCXPRT *),
 149     const char *name, const char *path, const char *prop,
 150     rpcprog_t pmin, rpcprog_t pmax, rpcvers_t vers,
 151     uint_t sndsize, uint_t rcvsize, int force)
 152 {
 153         rpcprog_t prog;
 154         char buf[16];
 155         FILE *fp;
 156
 157         for (prog = pmin; prog <= pmax; prog++) {
 158                 if (fmd_rpc_svc_create_local(disp, prog, vers,
 159                     sndsize, rcvsize, force) > 0) {
 160                         fmd_dprintf(FMD_DBG_RPC, "registered %s rpc service "
 161                             "as 0x%lx.%lx\n", name, prog, vers);
 162
 163                         /*
 164                          * To aid simulator scripts, save our RPC "digits" in
 165                          * the specified file for rendezvous with libfmd_adm.
 166                          */
 167                         if (path != NULL && (fp = fopen(path, "w")) != NULL) {
 168                                 (void) fprintf(fp, "%ld\n", prog);
 169                                 (void) fclose(fp);
 170                         }
 171
 172                         (void) snprintf(buf, sizeof (buf), "%ld", prog);
 173                         (void) fmd_conf_setprop(fmd.d_conf, prop, buf);
 174
 175                         return (0);
 176                 }
 177         }
 178
 179         return (-1); /* errno is set for us */
 180 }
 181
 182 void
 183 fmd_rpc_init(void)
 184 {
 185         int err, prog, mode = RPC_SVC_MT_USER;
 186         uint64_t sndsize = 0, rcvsize = 0;
 187         const char *s;
 188
 189         if (rpc_control(RPC_SVC_MTMODE_SET, &mode) == FALSE)
 190                 fmd_panic("failed to enable user-MT rpc mode");
 191
 192         (void) fmd_conf_getprop(fmd.d_conf, "rpc.sndsize", &sndsize);
 193         (void) fmd_conf_getprop(fmd.d_conf, "rpc.rcvsize", &rcvsize);
 194
 195         /*
 196          * Infer whether we are the "default" fault manager or an alternate one
 197          * based on whether the initial setting of rpc.adm.prog is non-zero.
 198          */
 199         (void) fmd_conf_getprop(fmd.d_conf, "rpc.adm.prog", &prog);
 200         (void) fmd_conf_getprop(fmd.d_conf, "rpc.adm.path", &s);
 201
 202         if (prog != 0) {
 203                 err = fmd_rpc_svc_init(fmd_adm_1, "FMD_ADM", s, "rpc.adm.prog",
 204                     FMD_ADM, FMD_ADM, FMD_ADM_VERSION_1,
 205                     (uint_t)sndsize, (uint_t)rcvsize, TRUE);
 206         } else {
 207                 err = fmd_rpc_svc_init(fmd_adm_1, "FMD_ADM", s, "rpc.adm.prog",
 208                     RPC_TRANS_MIN, RPC_TRANS_MAX, FMD_ADM_VERSION_1,
 209                     (uint_t)sndsize, (uint_t)rcvsize, FALSE);
 210         }
 211
 212         if (err != 0)
 213                 fmd_error(EFMD_EXIT, "failed to create rpc server bindings");
 214
 215         if (fmd_thread_create(fmd.d_rmod, (fmd_thread_f *)svc_run, 0) == NULL)
 216                 fmd_error(EFMD_EXIT, "failed to create rpc server thread");
 217 }
 218
 219 void
 220 fmd_rpc_fini(void)
 221 {
 222         rpcprog_t prog;
 223
 224         svc_exit(); /* force svc_run() threads to exit */
 225
 226         (void) fmd_conf_getprop(fmd.d_conf, "rpc.adm.prog", &prog);
 227         svc_unreg(prog, FMD_ADM_VERSION_1);
 228
 229         (void) fmd_conf_getprop(fmd.d_conf, "rpc.api.prog", &prog);
 230         svc_unreg(prog, FMD_API_VERSION_1);
 231 }
 232
 233 /*
 234  * Utillity function to fetch the XPRT's ucred and determine if we should deny
 235  * the request.  For now, we implement a simple policy of rejecting any caller
 236  * who does not have the PRIV_SYS_ADMIN bit in their Effective privilege set,
 237  * unless the caller is loading a module, which requires all privileges.
 238  */
 239 int
 240 fmd_rpc_deny(struct svc_req *rqp)
 241 {
 242         ucred_t *ucp = alloca(ucred_size());
 243         const priv_set_t *psp;
 244
 245         if (!fmd.d_booted) {
 246                 (void) pthread_mutex_lock(&fmd.d_fmd_lock);
 247                 while (!fmd.d_booted)
 248                         (void) pthread_cond_wait(&fmd.d_fmd_cv,
 249                             &fmd.d_fmd_lock);
 250                 (void) pthread_mutex_unlock(&fmd.d_fmd_lock);
 251         }
 252
 253         if (svc_getcallerucred(rqp->rq_xprt, &ucp) != 0 ||
 254             (psp = ucred_getprivset(ucp, PRIV_EFFECTIVE)) == NULL)
 255                 return (1); /* deny access if we can't get credentials */
 256
 257 #ifndef DEBUG
 258         /*
 259          * For convenience of testing, we only require all privileges for a
 260          * module load when running a non-DEBUG fault management daemon.
 261          */
 262         if (rqp->rq_proc == FMD_ADM_MODLOAD)
 263                 return (!priv_isfullset(psp));
 264 #endif
 265         return (!priv_ismember(psp, PRIV_SYS_ADMIN));
 266 }