11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * linux/net/sunrpc/auth_unix.c 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * UNIX-style authentication; no AUTH_SHORT support 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> 71da177e4SLinus Torvalds */ 81da177e4SLinus Torvalds 95a0e3ad6STejun Heo #include <linux/slab.h> 101da177e4SLinus Torvalds #include <linux/types.h> 111da177e4SLinus Torvalds #include <linux/sched.h> 121da177e4SLinus Torvalds #include <linux/module.h> 131da177e4SLinus Torvalds #include <linux/sunrpc/clnt.h> 141da177e4SLinus Torvalds #include <linux/sunrpc/auth.h> 15ae2975bcSEric W. Biederman #include <linux/user_namespace.h> 161da177e4SLinus Torvalds 171da177e4SLinus Torvalds #define NFS_NGROUPS 16 181da177e4SLinus Torvalds 191da177e4SLinus Torvalds struct unx_cred { 201da177e4SLinus Torvalds struct rpc_cred uc_base; 211da177e4SLinus Torvalds gid_t uc_gid; 221da177e4SLinus Torvalds gid_t uc_gids[NFS_NGROUPS]; 231da177e4SLinus Torvalds }; 241da177e4SLinus Torvalds #define uc_uid uc_base.cr_uid 251da177e4SLinus Torvalds 261da177e4SLinus Torvalds #define UNX_WRITESLACK (21 + (UNX_MAXNODENAME >> 2)) 271da177e4SLinus Torvalds 281da177e4SLinus Torvalds #ifdef RPC_DEBUG 291da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_AUTH 301da177e4SLinus Torvalds #endif 311da177e4SLinus Torvalds 321da177e4SLinus Torvalds static struct rpc_auth unix_auth; 33f1c0a861STrond Myklebust static const struct rpc_credops unix_credops; 341da177e4SLinus Torvalds 351da177e4SLinus Torvalds static struct rpc_auth * 361da177e4SLinus Torvalds unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 371da177e4SLinus Torvalds { 3846121cf7SChuck Lever dprintk("RPC: creating UNIX authenticator for client %p\n", 3946121cf7SChuck Lever clnt); 40f5c2187cSTrond Myklebust atomic_inc(&unix_auth.au_count); 411da177e4SLinus Torvalds return &unix_auth; 421da177e4SLinus Torvalds } 431da177e4SLinus Torvalds 441da177e4SLinus Torvalds static void 451da177e4SLinus Torvalds unx_destroy(struct rpc_auth *auth) 461da177e4SLinus Torvalds { 471da177e4SLinus Torvalds dprintk("RPC: destroying UNIX authenticator %p\n", auth); 483ab9bb72STrond Myklebust rpcauth_clear_credcache(auth->au_credcache); 491da177e4SLinus Torvalds } 501da177e4SLinus Torvalds 511da177e4SLinus Torvalds /* 521da177e4SLinus Torvalds * Lookup AUTH_UNIX creds for current process 531da177e4SLinus Torvalds */ 541da177e4SLinus Torvalds static struct rpc_cred * 551da177e4SLinus Torvalds unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 561da177e4SLinus Torvalds { 571da177e4SLinus Torvalds return rpcauth_lookup_credcache(auth, acred, flags); 581da177e4SLinus Torvalds } 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds static struct rpc_cred * 611da177e4SLinus Torvalds unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 621da177e4SLinus Torvalds { 631da177e4SLinus Torvalds struct unx_cred *cred; 64af093835STrond Myklebust unsigned int groups = 0; 65af093835STrond Myklebust unsigned int i; 661da177e4SLinus Torvalds 671da177e4SLinus Torvalds dprintk("RPC: allocating UNIX cred for uid %d gid %d\n", 681da177e4SLinus Torvalds acred->uid, acred->gid); 691da177e4SLinus Torvalds 700f38b873STrond Myklebust if (!(cred = kmalloc(sizeof(*cred), GFP_NOFS))) 711da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 721da177e4SLinus Torvalds 735fe4755eSTrond Myklebust rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops); 74fc432dd9STrond Myklebust cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE; 75af093835STrond Myklebust 76af093835STrond Myklebust if (acred->group_info != NULL) 77af093835STrond Myklebust groups = acred->group_info->ngroups; 781da177e4SLinus Torvalds if (groups > NFS_NGROUPS) 791da177e4SLinus Torvalds groups = NFS_NGROUPS; 801da177e4SLinus Torvalds 811da177e4SLinus Torvalds cred->uc_gid = acred->gid; 82ae2975bcSEric W. Biederman for (i = 0; i < groups; i++) { 83ae2975bcSEric W. Biederman gid_t gid; 84ae2975bcSEric W. Biederman gid = from_kgid(&init_user_ns, GROUP_AT(acred->group_info, i)); 85ae2975bcSEric W. Biederman cred->uc_gids[i] = gid; 86ae2975bcSEric W. Biederman } 871da177e4SLinus Torvalds if (i < NFS_NGROUPS) 881da177e4SLinus Torvalds cred->uc_gids[i] = NOGROUP; 891da177e4SLinus Torvalds 90696e38dfSTrond Myklebust return &cred->uc_base; 911da177e4SLinus Torvalds } 921da177e4SLinus Torvalds 931da177e4SLinus Torvalds static void 9431be5bf1STrond Myklebust unx_free_cred(struct unx_cred *unx_cred) 951da177e4SLinus Torvalds { 9631be5bf1STrond Myklebust dprintk("RPC: unx_free_cred %p\n", unx_cred); 9731be5bf1STrond Myklebust kfree(unx_cred); 9831be5bf1STrond Myklebust } 99696e38dfSTrond Myklebust 10031be5bf1STrond Myklebust static void 10131be5bf1STrond Myklebust unx_free_cred_callback(struct rcu_head *head) 10231be5bf1STrond Myklebust { 10331be5bf1STrond Myklebust struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu); 10431be5bf1STrond Myklebust unx_free_cred(unx_cred); 10531be5bf1STrond Myklebust } 10631be5bf1STrond Myklebust 10731be5bf1STrond Myklebust static void 10831be5bf1STrond Myklebust unx_destroy_cred(struct rpc_cred *cred) 10931be5bf1STrond Myklebust { 11031be5bf1STrond Myklebust call_rcu(&cred->cr_rcu, unx_free_cred_callback); 1111da177e4SLinus Torvalds } 1121da177e4SLinus Torvalds 1131da177e4SLinus Torvalds /* 1141da177e4SLinus Torvalds * Match credentials against current process creds. 1151da177e4SLinus Torvalds * The root_override argument takes care of cases where the caller may 1161da177e4SLinus Torvalds * request root creds (e.g. for NFS swapping). 1171da177e4SLinus Torvalds */ 1181da177e4SLinus Torvalds static int 1198a317760STrond Myklebust unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags) 1201da177e4SLinus Torvalds { 121696e38dfSTrond Myklebust struct unx_cred *cred = container_of(rcred, struct unx_cred, uc_base); 122af093835STrond Myklebust unsigned int groups = 0; 123af093835STrond Myklebust unsigned int i; 1241da177e4SLinus Torvalds 1251da177e4SLinus Torvalds 126af093835STrond Myklebust if (cred->uc_uid != acred->uid || cred->uc_gid != acred->gid) 1271da177e4SLinus Torvalds return 0; 1281da177e4SLinus Torvalds 129af093835STrond Myklebust if (acred->group_info != NULL) 1301da177e4SLinus Torvalds groups = acred->group_info->ngroups; 1311da177e4SLinus Torvalds if (groups > NFS_NGROUPS) 1321da177e4SLinus Torvalds groups = NFS_NGROUPS; 133ae2975bcSEric W. Biederman for (i = 0; i < groups ; i++) { 134ae2975bcSEric W. Biederman gid_t gid; 135ae2975bcSEric W. Biederman gid = from_kgid(&init_user_ns, GROUP_AT(acred->group_info, i)); 136ae2975bcSEric W. Biederman if (cred->uc_gids[i] != gid) 1371da177e4SLinus Torvalds return 0; 138ae2975bcSEric W. Biederman } 139dc6f55e9SNeilBrown if (groups < NFS_NGROUPS && 140dc6f55e9SNeilBrown cred->uc_gids[groups] != NOGROUP) 141dc6f55e9SNeilBrown return 0; 1421da177e4SLinus Torvalds return 1; 1431da177e4SLinus Torvalds } 1441da177e4SLinus Torvalds 1451da177e4SLinus Torvalds /* 1461da177e4SLinus Torvalds * Marshal credentials. 1471da177e4SLinus Torvalds * Maybe we should keep a cached credential for performance reasons. 1481da177e4SLinus Torvalds */ 149d8ed029dSAlexey Dobriyan static __be32 * 150d8ed029dSAlexey Dobriyan unx_marshal(struct rpc_task *task, __be32 *p) 1511da177e4SLinus Torvalds { 1521da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 153a17c2153STrond Myklebust struct unx_cred *cred = container_of(task->tk_rqstp->rq_cred, struct unx_cred, uc_base); 154d8ed029dSAlexey Dobriyan __be32 *base, *hold; 1551da177e4SLinus Torvalds int i; 1561da177e4SLinus Torvalds 1571da177e4SLinus Torvalds *p++ = htonl(RPC_AUTH_UNIX); 1581da177e4SLinus Torvalds base = p++; 1591da177e4SLinus Torvalds *p++ = htonl(jiffies/HZ); 1601da177e4SLinus Torvalds 1611da177e4SLinus Torvalds /* 1621da177e4SLinus Torvalds * Copy the UTS nodename captured when the client was created. 1631da177e4SLinus Torvalds */ 1641da177e4SLinus Torvalds p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen); 1651da177e4SLinus Torvalds 1661da177e4SLinus Torvalds *p++ = htonl((u32) cred->uc_uid); 1671da177e4SLinus Torvalds *p++ = htonl((u32) cred->uc_gid); 1681da177e4SLinus Torvalds hold = p++; 1691da177e4SLinus Torvalds for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++) 1701da177e4SLinus Torvalds *p++ = htonl((u32) cred->uc_gids[i]); 1711da177e4SLinus Torvalds *hold = htonl(p - hold - 1); /* gid array length */ 1721da177e4SLinus Torvalds *base = htonl((p - base - 1) << 2); /* cred length */ 1731da177e4SLinus Torvalds 1741da177e4SLinus Torvalds *p++ = htonl(RPC_AUTH_NULL); 1751da177e4SLinus Torvalds *p++ = htonl(0); 1761da177e4SLinus Torvalds 1771da177e4SLinus Torvalds return p; 1781da177e4SLinus Torvalds } 1791da177e4SLinus Torvalds 1801da177e4SLinus Torvalds /* 1811da177e4SLinus Torvalds * Refresh credentials. This is a no-op for AUTH_UNIX 1821da177e4SLinus Torvalds */ 1831da177e4SLinus Torvalds static int 1841da177e4SLinus Torvalds unx_refresh(struct rpc_task *task) 1851da177e4SLinus Torvalds { 186a17c2153STrond Myklebust set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags); 1871da177e4SLinus Torvalds return 0; 1881da177e4SLinus Torvalds } 1891da177e4SLinus Torvalds 190d8ed029dSAlexey Dobriyan static __be32 * 191d8ed029dSAlexey Dobriyan unx_validate(struct rpc_task *task, __be32 *p) 1921da177e4SLinus Torvalds { 1931da177e4SLinus Torvalds rpc_authflavor_t flavor; 1941da177e4SLinus Torvalds u32 size; 1951da177e4SLinus Torvalds 1961da177e4SLinus Torvalds flavor = ntohl(*p++); 1971da177e4SLinus Torvalds if (flavor != RPC_AUTH_NULL && 1981da177e4SLinus Torvalds flavor != RPC_AUTH_UNIX && 1991da177e4SLinus Torvalds flavor != RPC_AUTH_SHORT) { 2001da177e4SLinus Torvalds printk("RPC: bad verf flavor: %u\n", flavor); 2011da177e4SLinus Torvalds return NULL; 2021da177e4SLinus Torvalds } 2031da177e4SLinus Torvalds 2041da177e4SLinus Torvalds size = ntohl(*p++); 2051da177e4SLinus Torvalds if (size > RPC_MAX_AUTH_SIZE) { 2061da177e4SLinus Torvalds printk("RPC: giant verf size: %u\n", size); 2071da177e4SLinus Torvalds return NULL; 2081da177e4SLinus Torvalds } 209a17c2153STrond Myklebust task->tk_rqstp->rq_cred->cr_auth->au_rslack = (size >> 2) + 2; 2101da177e4SLinus Torvalds p += (size >> 2); 2111da177e4SLinus Torvalds 2121da177e4SLinus Torvalds return p; 2131da177e4SLinus Torvalds } 2141da177e4SLinus Torvalds 2155d8d9a4dSTrond Myklebust int __init rpc_init_authunix(void) 2169499b434STrond Myklebust { 2175d8d9a4dSTrond Myklebust return rpcauth_init_credcache(&unix_auth); 2185d8d9a4dSTrond Myklebust } 2195d8d9a4dSTrond Myklebust 2205d8d9a4dSTrond Myklebust void rpc_destroy_authunix(void) 2215d8d9a4dSTrond Myklebust { 2225d8d9a4dSTrond Myklebust rpcauth_destroy_credcache(&unix_auth); 2239499b434STrond Myklebust } 2249499b434STrond Myklebust 225f1c0a861STrond Myklebust const struct rpc_authops authunix_ops = { 2261da177e4SLinus Torvalds .owner = THIS_MODULE, 2271da177e4SLinus Torvalds .au_flavor = RPC_AUTH_UNIX, 2281da177e4SLinus Torvalds .au_name = "UNIX", 2291da177e4SLinus Torvalds .create = unx_create, 2301da177e4SLinus Torvalds .destroy = unx_destroy, 2311da177e4SLinus Torvalds .lookup_cred = unx_lookup_cred, 2321da177e4SLinus Torvalds .crcreate = unx_create_cred, 2331da177e4SLinus Torvalds }; 2341da177e4SLinus Torvalds 2351da177e4SLinus Torvalds static 2361da177e4SLinus Torvalds struct rpc_auth unix_auth = { 2371da177e4SLinus Torvalds .au_cslack = UNX_WRITESLACK, 2381da177e4SLinus Torvalds .au_rslack = 2, /* assume AUTH_NULL verf */ 2391da177e4SLinus Torvalds .au_ops = &authunix_ops, 24081039f1fSTrond Myklebust .au_flavor = RPC_AUTH_UNIX, 2411da177e4SLinus Torvalds .au_count = ATOMIC_INIT(0), 2421da177e4SLinus Torvalds }; 2431da177e4SLinus Torvalds 2441da177e4SLinus Torvalds static 245f1c0a861STrond Myklebust const struct rpc_credops unix_credops = { 2461da177e4SLinus Torvalds .cr_name = "AUTH_UNIX", 2471da177e4SLinus Torvalds .crdestroy = unx_destroy_cred, 2485c691044STrond Myklebust .crbind = rpcauth_generic_bind_cred, 2491da177e4SLinus Torvalds .crmatch = unx_match, 2501da177e4SLinus Torvalds .crmarshal = unx_marshal, 2511da177e4SLinus Torvalds .crrefresh = unx_refresh, 2521da177e4SLinus Torvalds .crvalidate = unx_validate, 2531da177e4SLinus Torvalds }; 254