src/afs/LINUX/osi_nfssrv.c

   1 /*
   2  * vi:set cin noet sw=4 tw=70:
   3  * Copyright 2006, International Business Machines Corporation and others.
   4  * All Rights Reserved.
   5  *
   6  * This software has been released under the terms of the IBM Public
   7  * License.  For details, see the LICENSE file in the top-level source
   8  * directory or online at http://www.openafs.org/dl/license10.html
   9  */
  10
  11 /*
  12  * Filesystem export operations for Linux
  13  */
  14 #include <afsconfig.h>
  15 #include "afs/param.h"
  16
  17
  18 #if !defined(AFS_NONFSTRANS) || defined(AFS_AIX_IAUTH_ENV)
  19 #include <linux/module.h> /* early to avoid printf->printk mapping */
  20 #include <linux/fs.h>
  21 #include "afs/sysincludes.h"
  22 #include "afsincludes.h"
  23 #include "nfsclient.h"
  24 #include <linux/sunrpc/svc.h>
  25 #include <linux/sunrpc/svcauth.h>
  26
  27 static unsigned long authtab_addr = 0;
  28 #if defined(module_param) && LINUX_VERSION_CODE > KERNEL_VERSION(2,6,9)
  29 module_param(authtab_addr, long, 0);
  30 #else
  31 MODULE_PARM(authtab_addr, "l");
  32 #endif
  33 MODULE_PARM_DESC(authtab_addr, "Address of the authtab array.");
  34
  35 extern struct auth_ops *authtab[] __attribute__((weak));
  36 static struct auth_ops **afs_authtab;
  37 static struct auth_ops *afs_new_authtab[RPC_AUTH_MAXFLAVOR];
  38 static struct auth_ops *afs_orig_authtab[RPC_AUTH_MAXFLAVOR];
  39
  40 static int whine_memory = 0;
  41
  42 afs_lock_t afs_xnfssrv;
  43
  44 struct nfs_server_thread {
  45     struct nfs_server_thread *next;     /* next in chain */
  46     pid_t pid;                          /* pid of this thread */
  47     int active;                         /* this thread is servicing an RPC */
  48     struct sockaddr_in client_addr;     /* latest client of this thread */
  49     int client_addrlen;
  50     afs_int32 uid;                      /* AFS UID/PAG for this thread */
  51     afs_int32 code;                     /* What should InitReq return? */
  52     int flavor;                         /* auth flavor */
  53     uid_t client_uid;                   /* UID claimed by client */
  54     gid_t client_gid;                   /* GID claimed by client */
  55     gid_t client_g0, client_g1;         /* groups claimed by client */
  56 };
  57
  58 static struct nfs_server_thread *nfssrv_list = 0;
  59
  60 static struct nfs_server_thread *find_nfs_thread(int create)
  61 {
  62     struct nfs_server_thread *this;
  63
  64     /* Check that this is an nfsd kernel thread */
  65     if (current->files != init_task.files || strcmp(current->comm, "nfsd"))
  66         return 0;
  67
  68     ObtainWriteLock(&afs_xnfssrv, 804);
  69     for (this = nfssrv_list; this; this = this->next)
  70         if (this->pid == current->pid)
  71             break;
  72     if (!this && create) {
  73         this = afs_osi_Alloc(sizeof(struct nfs_server_thread));
  74         if (this) {
  75             this->next = nfssrv_list;
  76             this->pid  = current->pid;
  77             this->client_addrlen = 0;
  78             nfssrv_list = this;
  79             printk("afs: added nfsd task %d/%d\n",
  80                    current->tgid, current->pid);
  81         } else if (!whine_memory) {
  82             whine_memory = 1;
  83             printk("afs: failed to allocate memory for nfsd task %d/%d\n",
  84                    current->tgid, current->pid);
  85         }
  86     }
  87     ReleaseWriteLock(&afs_xnfssrv);
  88     return this;
  89 }
  90
  91 static int
  92 svcauth_afs_accept(struct svc_rqst *rqstp, u32 *authp)
  93 {
  94     struct nfs_server_thread *ns;
  95     struct afs_exporter *outexp;
  96     afs_ucred_t *credp;
  97     struct sockaddr_in *addr;
  98     int code;
  99
 100     code = afs_orig_authtab[rqstp->rq_authop->flavour]->accept(rqstp, authp);
 101     if (code != SVC_OK)
 102         return code;
 103
 104     AFS_GLOCK();
 105     ns = find_nfs_thread(1);
 106     if (!ns) {
 107         AFS_GUNLOCK();
 108         /* XXX maybe we should fail this with rpc_system_err? */
 109         return SVC_OK;
 110     }
 111 #if HAVE_LINUX_SVC_ADDR_IN
 112     addr = svc_addr_in(rqstp);
 113 #else
 114     addr = &rqstp->rq_addr;
 115 #endif
 116
 117     ns->active          = 1;
 118     ns->flavor          = rqstp->rq_authop->flavour;
 119     ns->code            = EACCES;
 120     ns->client_addr     = *addr;
 121     ns->client_addrlen  = rqstp->rq_addrlen;
 122     ns->client_uid      = afs_cr_uid(&rqstp->rq_cred);
 123     ns->client_gid      = afs_cr_gid(&rqstp->rq_cred);
 124     if (afs_cr_group_info(&rqstp->rq_cred)->ngroups > 0)
 125         ns->client_g0   = GROUP_AT(afs_cr_group_info(&rqstp->rq_cred), 0);
 126     else
 127         ns->client_g0   = -1;
 128     if (afs_cr_group_info(&rqstp->rq_cred)->ngroups > 1)
 129         ns->client_g1   = GROUP_AT(afs_cr_group_info(&rqstp->rq_cred), 1);
 130     else
 131         ns->client_g1   = -1;
 132
 133     if (addr->sin_family != AF_INET) {
 134         printk("afs: NFS request from non-IPv4 client (family %d len %d)\n",
 135                addr->sin_family, rqstp->rq_addrlen);
 136         goto done;
 137     }
 138
 139     credp = crget();
 140     afs_set_cr_uid(credp, afs_cr_uid(&rqstp->rq_cred));
 141     afs_set_cr_gid(credp, afs_cr_gid(&rqstp->rq_cred));
 142     get_group_info(afs_cr_group_info(&rqstp->rq_cred));
 143     afs_set_cr_group_info(credp, afs_cr_group_info(&rqstp->rq_cred));
 144
 145     /* avoid creating wildcard entries by mapping anonymous
 146      * clients to afs_nobody */
 147     if (afs_cr_uid(credp) == -1)
 148         afs_set_cr_uid(credp, -2);
 149     code = afs_nfsclient_reqhandler(0, &credp, addr->sin_addr.s_addr,
 150                                     &ns->uid, &outexp);
 151     if (!code && outexp) EXP_RELE(outexp);
 152     if (!code) ns->code = 0;
 153     if (code)
 154         printk("afs: svcauth_afs_accept: afs_nfsclient_reqhandler: %d\n", code);
 155     crfree(credp);
 156
 157 done:
 158     AFS_GUNLOCK();
 159     return SVC_OK;
 160 }
 161
 162
 163 #if 0
 164 /* This doesn't work, because they helpfully NULL out rqstp->authop
 165  * before calling us, so we have no way to tell what the original
 166  * auth flavor was.
 167  */
 168 static int
 169 svcauth_afs_release(struct svc_rqst *rqstp)
 170 {
 171     struct nfs_server_thread *ns;
 172
 173     AFS_GLOCK();
 174     ns = find_nfs_thread(0);
 175     if (ns) ns->active = 0;
 176     AFS_GUNLOCK();
 177
 178     return afs_orig_authtab[rqstp->rq_authop->flavour]->release(rqstp);
 179 }
 180 #endif
 181
 182
 183 int osi_linux_nfs_initreq(struct vrequest *av, afs_ucred_t *cr, int *code)
 184 {
 185     struct nfs_server_thread *ns;
 186
 187     ns = find_nfs_thread(0);
 188     if (!ns || !ns->active)
 189         return 0;
 190
 191     *code = ns->code;
 192     if (!ns->code) {
 193         afs_cr_ruid(cr) = NFSXLATOR_CRED;
 194         av->uid = ns->uid;
 195     }
 196     return 1;
 197 }
 198
 199 void osi_linux_nfssrv_init(void)
 200 {
 201     int i;
 202
 203     nfssrv_list = 0;
 204     AFS_RWLOCK_INIT(&afs_xnfssrv, "afs_xnfssrv");
 205
 206     if (authtab && !IS_ERR(authtab))
 207            afs_authtab = authtab;
 208     else if (authtab_addr) afs_authtab = (struct auth_ops **)authtab_addr;
 209     else {
 210         printk("Warning: Unable to find the address of authtab\n");
 211         printk("NFS Translator hooks will not be installed\n");
 212         printk("To correct, specify authtab_addr=<authtab>\n");
 213         afs_authtab = 0;
 214         return;
 215     }
 216
 217     for (i = 0; i < RPC_AUTH_MAXFLAVOR; i++) {
 218         afs_orig_authtab[i] = afs_authtab[i];
 219         if (!afs_orig_authtab[i] || afs_orig_authtab[i]->flavour != i ||
 220             !try_module_get(afs_orig_authtab[i]->owner)) {
 221             afs_orig_authtab[i] = 0;
 222             continue;
 223         }
 224
 225         afs_new_authtab[i] = afs_osi_Alloc(sizeof(struct auth_ops));
 226         osi_Assert(afs_new_authtab[i] != NULL);
 227         *(afs_new_authtab[i]) = *(afs_orig_authtab[i]);
 228         afs_new_authtab[i]->owner = THIS_MODULE;
 229         afs_new_authtab[i]->accept = svcauth_afs_accept;
 230         /* afs_new_authtab[i]->release = svcauth_afs_release; */
 231         svc_auth_unregister(i);
 232         svc_auth_register(i, afs_new_authtab[i]);
 233     }
 234 }
 235
 236 void osi_linux_nfssrv_shutdown(void)
 237 {
 238     struct nfs_server_thread *next;
 239     int i;
 240
 241     if (afs_authtab) {
 242         for (i = 0; i < RPC_AUTH_MAXFLAVOR; i++) {
 243             if (!afs_orig_authtab[i])
 244                 continue;
 245             svc_auth_unregister(i);
 246             svc_auth_register(i, afs_orig_authtab[i]);
 247             module_put(afs_orig_authtab[i]->owner);
 248             afs_osi_Free(afs_new_authtab[i], sizeof(struct auth_ops));
 249         }
 250     }
 251
 252     AFS_GLOCK();
 253     ObtainWriteLock(&afs_xnfssrv, 805);
 254     while (nfssrv_list) {
 255         next = nfssrv_list->next;
 256         afs_osi_Free(nfssrv_list, sizeof(struct nfs_server_thread));
 257         nfssrv_list = next;
 258     }
 259     ReleaseWriteLock(&afs_xnfssrv);
 260     AFS_GUNLOCK();
 261 }
 262 #endif /* AFS_NONFSTRANS */
 263