1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_kgssapi.h" 38 39 #include <fs/nfs/nfsport.h> 40 41 #include <rpc/rpc.h> 42 #include <rpc/rpcsec_gss.h> 43 #include <rpc/replay.h> 44 45 46 NFSDLOCKMUTEX; 47 48 extern SVCPOOL *nfscbd_pool; 49 50 static int nfs_cbproc(struct nfsrv_descript *, u_int32_t); 51 52 extern u_long sb_max_adj; 53 extern int nfs_numnfscbd; 54 extern int nfscl_debuglevel; 55 56 /* 57 * NFS client system calls for handling callbacks. 58 */ 59 60 /* 61 * Handles server to client callbacks. 62 */ 63 static void 64 nfscb_program(struct svc_req *rqst, SVCXPRT *xprt) 65 { 66 struct nfsrv_descript nd; 67 int cacherep, credflavor; 68 69 memset(&nd, 0, sizeof(nd)); 70 if (rqst->rq_proc != NFSPROC_NULL && 71 rqst->rq_proc != NFSV4PROC_CBCOMPOUND) { 72 svcerr_noproc(rqst); 73 svc_freereq(rqst); 74 return; 75 } 76 nd.nd_procnum = rqst->rq_proc; 77 nd.nd_flag = (ND_NFSCB | ND_NFSV4); 78 79 /* 80 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 - 81 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP 82 * mounts. 83 */ 84 nd.nd_mrep = rqst->rq_args; 85 rqst->rq_args = NULL; 86 newnfs_realign(&nd.nd_mrep, M_WAITOK); 87 nd.nd_md = nd.nd_mrep; 88 nd.nd_dpos = mtod(nd.nd_md, caddr_t); 89 nd.nd_nam = svc_getrpccaller(rqst); 90 nd.nd_nam2 = rqst->rq_addr; 91 nd.nd_mreq = NULL; 92 nd.nd_cred = NULL; 93 94 NFSCL_DEBUG(1, "cbproc=%d\n",nd.nd_procnum); 95 if (nd.nd_procnum != NFSPROC_NULL) { 96 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) { 97 svcerr_weakauth(rqst); 98 svc_freereq(rqst); 99 m_freem(nd.nd_mrep); 100 return; 101 } 102 103 /* For now, I don't care what credential flavor was used. */ 104 #ifdef notyet 105 #ifdef MAC 106 mac_cred_associate_nfsd(nd.nd_cred); 107 #endif 108 #endif 109 cacherep = nfs_cbproc(&nd, rqst->rq_xid); 110 } else { 111 NFSMGET(nd.nd_mreq); 112 nd.nd_mreq->m_len = 0; 113 cacherep = RC_REPLY; 114 } 115 if (nd.nd_mrep != NULL) 116 m_freem(nd.nd_mrep); 117 118 if (nd.nd_cred != NULL) 119 crfree(nd.nd_cred); 120 121 if (cacherep == RC_DROPIT) { 122 if (nd.nd_mreq != NULL) 123 m_freem(nd.nd_mreq); 124 svc_freereq(rqst); 125 return; 126 } 127 128 if (nd.nd_mreq == NULL) { 129 svcerr_decode(rqst); 130 svc_freereq(rqst); 131 return; 132 } 133 134 if (nd.nd_repstat & NFSERR_AUTHERR) { 135 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR); 136 if (nd.nd_mreq != NULL) 137 m_freem(nd.nd_mreq); 138 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) 139 svcerr_systemerr(rqst); 140 else 141 NFSCL_DEBUG(1, "cbrep sent\n"); 142 svc_freereq(rqst); 143 } 144 145 /* 146 * Check the cache and, optionally, do the RPC. 147 * Return the appropriate cache response. 148 */ 149 static int 150 nfs_cbproc(struct nfsrv_descript *nd, u_int32_t xid) 151 { 152 struct thread *td = curthread; 153 int cacherep; 154 155 if (nd->nd_nam2 == NULL) 156 nd->nd_flag |= ND_STREAMSOCK; 157 158 nfscl_docb(nd, td); 159 if (nd->nd_repstat == NFSERR_DONTREPLY) 160 cacherep = RC_DROPIT; 161 else 162 cacherep = RC_REPLY; 163 return (cacherep); 164 } 165 166 /* 167 * Adds a socket to the list for servicing by nfscbds. 168 */ 169 int 170 nfscbd_addsock(struct file *fp) 171 { 172 int siz; 173 struct socket *so; 174 int error; 175 SVCXPRT *xprt; 176 177 so = fp->f_data; 178 179 siz = sb_max_adj; 180 error = soreserve(so, siz, siz); 181 if (error) 182 return (error); 183 184 /* 185 * Steal the socket from userland so that it doesn't close 186 * unexpectedly. 187 */ 188 if (so->so_type == SOCK_DGRAM) 189 xprt = svc_dg_create(nfscbd_pool, so, 0, 0); 190 else 191 xprt = svc_vc_create(nfscbd_pool, so, 0, 0); 192 if (xprt) { 193 fp->f_ops = &badfileops; 194 fp->f_data = NULL; 195 svc_reg(xprt, NFS_CALLBCKPROG, NFSV4_CBVERS, nfscb_program, 196 NULL); 197 SVC_RELEASE(xprt); 198 } 199 200 return (0); 201 } 202 203 /* 204 * Called by nfssvc() for nfscbds. Just loops around servicing rpc requests 205 * until it is killed by a signal. 206 * 207 * For now, only support callbacks via RPCSEC_GSS if there is a KerberosV 208 * keytab entry with a host based entry in it on the client. (I'm not even 209 * sure that getting Acceptor credentials for a user principal with a 210 * credentials cache is possible, but even if it is, major changes to the 211 * kgssapi would be required.) 212 * I don't believe that this is a serious limitation since, as of 2009, most 213 * NFSv4 servers supporting callbacks are using AUTH_SYS for callbacks even 214 * when the client is using RPCSEC_GSS. (This BSD server uses AUTH_SYS 215 * for callbacks unless nfsrv_gsscallbackson is set non-zero.) 216 */ 217 int 218 nfscbd_nfsd(struct thread *td, struct nfsd_nfscbd_args *args) 219 { 220 char principal[128]; 221 int error; 222 223 if (args != NULL) { 224 error = copyinstr(args->principal, principal, 225 sizeof(principal), NULL); 226 if (error) 227 return (error); 228 } else { 229 principal[0] = '\0'; 230 } 231 232 /* 233 * Only the first nfsd actually does any work. The RPC code 234 * adds threads to it as needed. Any extra processes offered 235 * by nfsd just exit. If nfsd is new enough, it will call us 236 * once with a structure that specifies how many threads to 237 * use. 238 */ 239 NFSD_LOCK(); 240 if (nfs_numnfscbd == 0) { 241 nfs_numnfscbd++; 242 243 NFSD_UNLOCK(); 244 245 if (principal[0] != '\0') 246 rpc_gss_set_svc_name_call(principal, "kerberosv5", 247 GSS_C_INDEFINITE, NFS_CALLBCKPROG, NFSV4_CBVERS); 248 249 nfscbd_pool->sp_minthreads = 4; 250 nfscbd_pool->sp_maxthreads = 4; 251 252 svc_run(nfscbd_pool); 253 254 rpc_gss_clear_svc_name_call(NFS_CALLBCKPROG, NFSV4_CBVERS); 255 256 NFSD_LOCK(); 257 nfs_numnfscbd--; 258 nfsrvd_cbinit(1); 259 } 260 NFSD_UNLOCK(); 261 262 return (0); 263 } 264 265 /* 266 * Initialize the data structures for the server. 267 * Handshake with any new nfsds starting up to avoid any chance of 268 * corruption. 269 */ 270 void 271 nfsrvd_cbinit(int terminating) 272 { 273 274 NFSD_LOCK_ASSERT(); 275 276 if (terminating) { 277 /* Wait for any xprt registrations to complete. */ 278 while (nfs_numnfscbd > 0) 279 msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO, 280 "nfscbdt", 0); 281 } 282 283 if (nfscbd_pool == NULL) { 284 NFSD_UNLOCK(); 285 nfscbd_pool = svcpool_create("nfscbd", NULL); 286 nfscbd_pool->sp_rcache = NULL; 287 nfscbd_pool->sp_assign = NULL; 288 nfscbd_pool->sp_done = NULL; 289 NFSD_LOCK(); 290 } 291 } 292 293