1 /* $NetBSD: nfs_clkrpc.c,v 1.3 2024/07/05 04:31:52 rin Exp $ */ 2 /*- 3 * Copyright (c) 1989, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Rick Macklem at The University of Guelph. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 */ 34 35 #include <sys/cdefs.h> 36 /* __FBSDID("FreeBSD: head/sys/fs/nfsclient/nfs_clkrpc.c 255216 2013-09-04 22:47:56Z rmacklem "); */ 37 __RCSID("$NetBSD: nfs_clkrpc.c,v 1.3 2024/07/05 04:31:52 rin Exp $"); 38 39 #ifdef NOTYET /* _KERNEL_OPT */ 40 #include "opt_kgssapi.h" 41 #endif 42 43 #include <fs/nfs/common/nfsport.h> 44 45 #include <rpc/rpc.h> 46 #include <rpc/rpcsec_gss.h> 47 #include <rpc/replay.h> 48 49 50 NFSDLOCKMUTEX; 51 52 extern SVCPOOL *nfscbd_pool; 53 54 static int nfs_cbproc(struct nfsrv_descript *, u_int32_t); 55 56 extern u_long sb_max_adj; 57 extern int nfs_numnfscbd; 58 extern int nfscl_debuglevel; 59 60 /* 61 * NFS client system calls for handling callbacks. 62 */ 63 64 /* 65 * Handles server to client callbacks. 66 */ 67 static void 68 nfscb_program(struct svc_req *rqst, SVCXPRT *xprt) 69 { 70 struct nfsrv_descript nd; 71 int cacherep, credflavor; 72 73 memset(&nd, 0, sizeof(nd)); 74 if (rqst->rq_proc != NFSPROC_NULL && 75 rqst->rq_proc != NFSV4PROC_CBCOMPOUND) { 76 svcerr_noproc(rqst); 77 svc_freereq(rqst); 78 return; 79 } 80 nd.nd_procnum = rqst->rq_proc; 81 nd.nd_flag = (ND_NFSCB | ND_NFSV4); 82 83 /* 84 * Note: we want rq_addr, not svc_getrpccaller for nd_nam2 - 85 * NFS_SRVMAXDATA uses a NULL value for nd_nam2 to detect TCP 86 * mounts. 87 */ 88 nd.nd_mrep = rqst->rq_args; 89 rqst->rq_args = NULL; 90 newnfs_realign(&nd.nd_mrep, M_WAITOK); 91 nd.nd_md = nd.nd_mrep; 92 nd.nd_dpos = mtod(nd.nd_md, caddr_t); 93 nd.nd_nam = svc_getrpccaller(rqst); 94 nd.nd_nam2 = rqst->rq_addr; 95 nd.nd_mreq = NULL; 96 nd.nd_cred = NULL; 97 98 NFSCL_DEBUG(1, "cbproc=%d\n",nd.nd_procnum); 99 if (nd.nd_procnum != NFSPROC_NULL) { 100 if (!svc_getcred(rqst, &nd.nd_cred, &credflavor)) { 101 svcerr_weakauth(rqst); 102 svc_freereq(rqst); 103 m_freem(nd.nd_mrep); 104 return; 105 } 106 107 /* For now, I don't care what credential flavor was used. */ 108 #ifdef notyet 109 #ifdef MAC 110 mac_cred_associate_nfsd(nd.nd_cred); 111 #endif 112 #endif 113 cacherep = nfs_cbproc(&nd, rqst->rq_xid); 114 } else { 115 NFSMGET(nd.nd_mreq); 116 nd.nd_mreq->m_len = 0; 117 cacherep = RC_REPLY; 118 } 119 m_freem(nd.nd_mrep); 120 121 if (nd.nd_cred != NULL) 122 crfree(nd.nd_cred); 123 124 if (cacherep == RC_DROPIT) { 125 m_freem(nd.nd_mreq); 126 svc_freereq(rqst); 127 return; 128 } 129 130 if (nd.nd_mreq == NULL) { 131 svcerr_decode(rqst); 132 svc_freereq(rqst); 133 return; 134 } 135 136 if (nd.nd_repstat & NFSERR_AUTHERR) { 137 svcerr_auth(rqst, nd.nd_repstat & ~NFSERR_AUTHERR); 138 m_freem(nd.nd_mreq); 139 } else if (!svc_sendreply_mbuf(rqst, nd.nd_mreq)) 140 svcerr_systemerr(rqst); 141 else 142 NFSCL_DEBUG(1, "cbrep sent\n"); 143 svc_freereq(rqst); 144 } 145 146 /* 147 * Check the cache and, optionally, do the RPC. 148 * Return the appropriate cache response. 149 */ 150 static int 151 nfs_cbproc(struct nfsrv_descript *nd, u_int32_t xid) 152 { 153 struct thread *td = curthread; 154 int cacherep; 155 156 if (nd->nd_nam2 == NULL) 157 nd->nd_flag |= ND_STREAMSOCK; 158 159 nfscl_docb(nd, td); 160 if (nd->nd_repstat == NFSERR_DONTREPLY) 161 cacherep = RC_DROPIT; 162 else 163 cacherep = RC_REPLY; 164 return (cacherep); 165 } 166 167 /* 168 * Adds a socket to the list for servicing by nfscbds. 169 */ 170 int 171 nfscbd_addsock(struct file *fp) 172 { 173 int siz; 174 struct socket *so; 175 int error; 176 SVCXPRT *xprt; 177 178 so = fp->f_data; 179 180 siz = sb_max_adj; 181 error = soreserve(so, siz, siz); 182 if (error) 183 return (error); 184 185 /* 186 * Steal the socket from userland so that it doesn't close 187 * unexpectedly. 188 */ 189 if (so->so_type == SOCK_DGRAM) 190 xprt = svc_dg_create(nfscbd_pool, so, 0, 0); 191 else 192 xprt = svc_vc_create(nfscbd_pool, so, 0, 0); 193 if (xprt) { 194 fp->f_ops = &badfileops; 195 fp->f_data = NULL; 196 svc_reg(xprt, NFS_CALLBCKPROG, NFSV4_CBVERS, nfscb_program, 197 NULL); 198 SVC_RELEASE(xprt); 199 } 200 201 return (0); 202 } 203 204 /* 205 * Called by nfssvc() for nfscbds. Just loops around servicing rpc requests 206 * until it is killed by a signal. 207 * 208 * For now, only support callbacks via RPCSEC_GSS if there is a KerberosV 209 * keytab entry with a host based entry in it on the client. (I'm not even 210 * sure that getting Acceptor credentials for a user principal with a 211 * credentials cache is possible, but even if it is, major changes to the 212 * kgssapi would be required.) 213 * I don't believe that this is a serious limitation since, as of 2009, most 214 * NFSv4 servers supporting callbacks are using AUTH_SYS for callbacks even 215 * when the client is using RPCSEC_GSS. (This BSD server uses AUTH_SYS 216 * for callbacks unless nfsrv_gsscallbackson is set non-zero.) 217 */ 218 int 219 nfscbd_nfsd(struct thread *td, struct nfsd_nfscbd_args *args) 220 { 221 char principal[128]; 222 int error; 223 224 if (args != NULL) { 225 error = copyinstr(args->principal, principal, 226 sizeof(principal), NULL); 227 if (error) 228 return (error); 229 } else { 230 principal[0] = '\0'; 231 } 232 233 /* 234 * Only the first nfsd actually does any work. The RPC code 235 * adds threads to it as needed. Any extra processes offered 236 * by nfsd just exit. If nfsd is new enough, it will call us 237 * once with a structure that specifies how many threads to 238 * use. 239 */ 240 NFSD_LOCK(); 241 if (nfs_numnfscbd == 0) { 242 nfs_numnfscbd++; 243 244 NFSD_UNLOCK(); 245 246 if (principal[0] != '\0') 247 rpc_gss_set_svc_name_call(principal, "kerberosv5", 248 GSS_C_INDEFINITE, NFS_CALLBCKPROG, NFSV4_CBVERS); 249 250 nfscbd_pool->sp_minthreads = 4; 251 nfscbd_pool->sp_maxthreads = 4; 252 253 svc_run(nfscbd_pool); 254 255 rpc_gss_clear_svc_name_call(NFS_CALLBCKPROG, NFSV4_CBVERS); 256 257 NFSD_LOCK(); 258 nfs_numnfscbd--; 259 nfsrvd_cbinit(1); 260 } 261 NFSD_UNLOCK(); 262 263 return (0); 264 } 265 266 /* 267 * Initialize the data structures for the server. 268 * Handshake with any new nfsds starting up to avoid any chance of 269 * corruption. 270 */ 271 void 272 nfsrvd_cbinit(int terminating) 273 { 274 275 NFSD_LOCK_ASSERT(); 276 277 if (terminating) { 278 /* Wait for any xprt registrations to complete. */ 279 while (nfs_numnfscbd > 0) 280 msleep(&nfs_numnfscbd, NFSDLOCKMUTEXPTR, PZERO, 281 "nfscbdt", 0); 282 } 283 284 if (nfscbd_pool == NULL) { 285 NFSD_UNLOCK(); 286 nfscbd_pool = svcpool_create("nfscbd", NULL); 287 nfscbd_pool->sp_rcache = NULL; 288 nfscbd_pool->sp_assign = NULL; 289 nfscbd_pool->sp_done = NULL; 290 NFSD_LOCK(); 291 } 292 } 293 294