1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * linux/net/sunrpc/auth_unix.c 41da177e4SLinus Torvalds * 51da177e4SLinus Torvalds * UNIX-style authentication; no AUTH_SHORT support 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> 81da177e4SLinus Torvalds */ 91da177e4SLinus Torvalds 105a0e3ad6STejun Heo #include <linux/slab.h> 111da177e4SLinus Torvalds #include <linux/types.h> 121da177e4SLinus Torvalds #include <linux/sched.h> 131da177e4SLinus Torvalds #include <linux/module.h> 141da177e4SLinus Torvalds #include <linux/sunrpc/clnt.h> 151da177e4SLinus Torvalds #include <linux/sunrpc/auth.h> 16ae2975bcSEric W. Biederman #include <linux/user_namespace.h> 171da177e4SLinus Torvalds 181da177e4SLinus Torvalds struct unx_cred { 191da177e4SLinus Torvalds struct rpc_cred uc_base; 207eaf040bSEric W. Biederman kgid_t uc_gid; 215786461bSKinglong Mee kgid_t uc_gids[UNX_NGROUPS]; 221da177e4SLinus Torvalds }; 231da177e4SLinus Torvalds #define uc_uid uc_base.cr_uid 241da177e4SLinus Torvalds 25f895b252SJeff Layton #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 261da177e4SLinus Torvalds # define RPCDBG_FACILITY RPCDBG_AUTH 271da177e4SLinus Torvalds #endif 281da177e4SLinus Torvalds 291da177e4SLinus Torvalds static struct rpc_auth unix_auth; 30f1c0a861STrond Myklebust static const struct rpc_credops unix_credops; 311da177e4SLinus Torvalds 321da177e4SLinus Torvalds static struct rpc_auth * 33c2190661STrond Myklebust unx_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt) 341da177e4SLinus Torvalds { 3546121cf7SChuck Lever dprintk("RPC: creating UNIX authenticator for client %p\n", 3646121cf7SChuck Lever clnt); 37f5c2187cSTrond Myklebust atomic_inc(&unix_auth.au_count); 381da177e4SLinus Torvalds return &unix_auth; 391da177e4SLinus Torvalds } 401da177e4SLinus Torvalds 411da177e4SLinus Torvalds static void 421da177e4SLinus Torvalds unx_destroy(struct rpc_auth *auth) 431da177e4SLinus Torvalds { 441da177e4SLinus Torvalds dprintk("RPC: destroying UNIX authenticator %p\n", auth); 453ab9bb72STrond Myklebust rpcauth_clear_credcache(auth->au_credcache); 461da177e4SLinus Torvalds } 471da177e4SLinus Torvalds 481e035d06SFrank Sorenson static int 491e035d06SFrank Sorenson unx_hash_cred(struct auth_cred *acred, unsigned int hashbits) 501e035d06SFrank Sorenson { 511e035d06SFrank Sorenson return hash_64(from_kgid(&init_user_ns, acred->gid) | 521e035d06SFrank Sorenson ((u64)from_kuid(&init_user_ns, acred->uid) << 531e035d06SFrank Sorenson (sizeof(gid_t) * 8)), hashbits); 541e035d06SFrank Sorenson } 551e035d06SFrank Sorenson 561da177e4SLinus Torvalds /* 571da177e4SLinus Torvalds * Lookup AUTH_UNIX creds for current process 581da177e4SLinus Torvalds */ 591da177e4SLinus Torvalds static struct rpc_cred * 601da177e4SLinus Torvalds unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) 611da177e4SLinus Torvalds { 623c6e0bc8SJeff Layton return rpcauth_lookup_credcache(auth, acred, flags, GFP_NOFS); 631da177e4SLinus Torvalds } 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds static struct rpc_cred * 663c6e0bc8SJeff Layton unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags, gfp_t gfp) 671da177e4SLinus Torvalds { 681da177e4SLinus Torvalds struct unx_cred *cred; 69af093835STrond Myklebust unsigned int groups = 0; 70af093835STrond Myklebust unsigned int i; 711da177e4SLinus Torvalds 721da177e4SLinus Torvalds dprintk("RPC: allocating UNIX cred for uid %d gid %d\n", 73cdba321eSEric W. Biederman from_kuid(&init_user_ns, acred->uid), 74cdba321eSEric W. Biederman from_kgid(&init_user_ns, acred->gid)); 751da177e4SLinus Torvalds 763c6e0bc8SJeff Layton if (!(cred = kmalloc(sizeof(*cred), gfp))) 771da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 781da177e4SLinus Torvalds 795fe4755eSTrond Myklebust rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops); 80fc432dd9STrond Myklebust cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE; 81af093835STrond Myklebust 82af093835STrond Myklebust if (acred->group_info != NULL) 83af093835STrond Myklebust groups = acred->group_info->ngroups; 845786461bSKinglong Mee if (groups > UNX_NGROUPS) 855786461bSKinglong Mee groups = UNX_NGROUPS; 861da177e4SLinus Torvalds 871da177e4SLinus Torvalds cred->uc_gid = acred->gid; 889132adb0SEric W. Biederman for (i = 0; i < groups; i++) 8981243eacSAlexey Dobriyan cred->uc_gids[i] = acred->group_info->gid[i]; 905786461bSKinglong Mee if (i < UNX_NGROUPS) 91bf37f794SEric W. Biederman cred->uc_gids[i] = INVALID_GID; 921da177e4SLinus Torvalds 93696e38dfSTrond Myklebust return &cred->uc_base; 941da177e4SLinus Torvalds } 951da177e4SLinus Torvalds 961da177e4SLinus Torvalds static void 9731be5bf1STrond Myklebust unx_free_cred(struct unx_cred *unx_cred) 981da177e4SLinus Torvalds { 9931be5bf1STrond Myklebust dprintk("RPC: unx_free_cred %p\n", unx_cred); 10031be5bf1STrond Myklebust kfree(unx_cred); 10131be5bf1STrond Myklebust } 102696e38dfSTrond Myklebust 10331be5bf1STrond Myklebust static void 10431be5bf1STrond Myklebust unx_free_cred_callback(struct rcu_head *head) 10531be5bf1STrond Myklebust { 10631be5bf1STrond Myklebust struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu); 10731be5bf1STrond Myklebust unx_free_cred(unx_cred); 10831be5bf1STrond Myklebust } 10931be5bf1STrond Myklebust 11031be5bf1STrond Myklebust static void 11131be5bf1STrond Myklebust unx_destroy_cred(struct rpc_cred *cred) 11231be5bf1STrond Myklebust { 11331be5bf1STrond Myklebust call_rcu(&cred->cr_rcu, unx_free_cred_callback); 1141da177e4SLinus Torvalds } 1151da177e4SLinus Torvalds 1161da177e4SLinus Torvalds /* 1171da177e4SLinus Torvalds * Match credentials against current process creds. 1181da177e4SLinus Torvalds * The root_override argument takes care of cases where the caller may 1191da177e4SLinus Torvalds * request root creds (e.g. for NFS swapping). 1201da177e4SLinus Torvalds */ 1211da177e4SLinus Torvalds static int 1228a317760STrond Myklebust unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags) 1231da177e4SLinus Torvalds { 124696e38dfSTrond Myklebust struct unx_cred *cred = container_of(rcred, struct unx_cred, uc_base); 125af093835STrond Myklebust unsigned int groups = 0; 126af093835STrond Myklebust unsigned int i; 1271da177e4SLinus Torvalds 1281da177e4SLinus Torvalds 1290b4d51b0SEric W. Biederman if (!uid_eq(cred->uc_uid, acred->uid) || !gid_eq(cred->uc_gid, acred->gid)) 1301da177e4SLinus Torvalds return 0; 1311da177e4SLinus Torvalds 132af093835STrond Myklebust if (acred->group_info != NULL) 1331da177e4SLinus Torvalds groups = acred->group_info->ngroups; 1345786461bSKinglong Mee if (groups > UNX_NGROUPS) 1355786461bSKinglong Mee groups = UNX_NGROUPS; 1369132adb0SEric W. Biederman for (i = 0; i < groups ; i++) 13781243eacSAlexey Dobriyan if (!gid_eq(cred->uc_gids[i], acred->group_info->gid[i])) 1381da177e4SLinus Torvalds return 0; 1395786461bSKinglong Mee if (groups < UNX_NGROUPS && gid_valid(cred->uc_gids[groups])) 140dc6f55e9SNeilBrown return 0; 1411da177e4SLinus Torvalds return 1; 1421da177e4SLinus Torvalds } 1431da177e4SLinus Torvalds 1441da177e4SLinus Torvalds /* 1451da177e4SLinus Torvalds * Marshal credentials. 1461da177e4SLinus Torvalds * Maybe we should keep a cached credential for performance reasons. 1471da177e4SLinus Torvalds */ 148d8ed029dSAlexey Dobriyan static __be32 * 149d8ed029dSAlexey Dobriyan unx_marshal(struct rpc_task *task, __be32 *p) 1501da177e4SLinus Torvalds { 1511da177e4SLinus Torvalds struct rpc_clnt *clnt = task->tk_client; 152a17c2153STrond Myklebust struct unx_cred *cred = container_of(task->tk_rqstp->rq_cred, struct unx_cred, uc_base); 153d8ed029dSAlexey Dobriyan __be32 *base, *hold; 1541da177e4SLinus Torvalds int i; 1551da177e4SLinus Torvalds 1561da177e4SLinus Torvalds *p++ = htonl(RPC_AUTH_UNIX); 1571da177e4SLinus Torvalds base = p++; 1581da177e4SLinus Torvalds *p++ = htonl(jiffies/HZ); 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds /* 1611da177e4SLinus Torvalds * Copy the UTS nodename captured when the client was created. 1621da177e4SLinus Torvalds */ 1631da177e4SLinus Torvalds p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen); 1641da177e4SLinus Torvalds 165a570abbbSEric W. Biederman *p++ = htonl((u32) from_kuid(&init_user_ns, cred->uc_uid)); 166a570abbbSEric W. Biederman *p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gid)); 1671da177e4SLinus Torvalds hold = p++; 1685786461bSKinglong Mee for (i = 0; i < UNX_NGROUPS && gid_valid(cred->uc_gids[i]); i++) 169a570abbbSEric W. Biederman *p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gids[i])); 1701da177e4SLinus Torvalds *hold = htonl(p - hold - 1); /* gid array length */ 1711da177e4SLinus Torvalds *base = htonl((p - base - 1) << 2); /* cred length */ 1721da177e4SLinus Torvalds 1731da177e4SLinus Torvalds *p++ = htonl(RPC_AUTH_NULL); 1741da177e4SLinus Torvalds *p++ = htonl(0); 1751da177e4SLinus Torvalds 1761da177e4SLinus Torvalds return p; 1771da177e4SLinus Torvalds } 1781da177e4SLinus Torvalds 1791da177e4SLinus Torvalds /* 1801da177e4SLinus Torvalds * Refresh credentials. This is a no-op for AUTH_UNIX 1811da177e4SLinus Torvalds */ 1821da177e4SLinus Torvalds static int 1831da177e4SLinus Torvalds unx_refresh(struct rpc_task *task) 1841da177e4SLinus Torvalds { 185a17c2153STrond Myklebust set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags); 1861da177e4SLinus Torvalds return 0; 1871da177e4SLinus Torvalds } 1881da177e4SLinus Torvalds 189d8ed029dSAlexey Dobriyan static __be32 * 190d8ed029dSAlexey Dobriyan unx_validate(struct rpc_task *task, __be32 *p) 1911da177e4SLinus Torvalds { 1921da177e4SLinus Torvalds rpc_authflavor_t flavor; 1931da177e4SLinus Torvalds u32 size; 1941da177e4SLinus Torvalds 1951da177e4SLinus Torvalds flavor = ntohl(*p++); 1961da177e4SLinus Torvalds if (flavor != RPC_AUTH_NULL && 1971da177e4SLinus Torvalds flavor != RPC_AUTH_UNIX && 1981da177e4SLinus Torvalds flavor != RPC_AUTH_SHORT) { 1991da177e4SLinus Torvalds printk("RPC: bad verf flavor: %u\n", flavor); 20035fa5f7bSAndy Adamson return ERR_PTR(-EIO); 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds 2031da177e4SLinus Torvalds size = ntohl(*p++); 2041da177e4SLinus Torvalds if (size > RPC_MAX_AUTH_SIZE) { 2051da177e4SLinus Torvalds printk("RPC: giant verf size: %u\n", size); 20635fa5f7bSAndy Adamson return ERR_PTR(-EIO); 2071da177e4SLinus Torvalds } 208a17c2153STrond Myklebust task->tk_rqstp->rq_cred->cr_auth->au_rslack = (size >> 2) + 2; 2091da177e4SLinus Torvalds p += (size >> 2); 2101da177e4SLinus Torvalds 2111da177e4SLinus Torvalds return p; 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds 2145d8d9a4dSTrond Myklebust int __init rpc_init_authunix(void) 2159499b434STrond Myklebust { 2165d8d9a4dSTrond Myklebust return rpcauth_init_credcache(&unix_auth); 2175d8d9a4dSTrond Myklebust } 2185d8d9a4dSTrond Myklebust 2195d8d9a4dSTrond Myklebust void rpc_destroy_authunix(void) 2205d8d9a4dSTrond Myklebust { 2215d8d9a4dSTrond Myklebust rpcauth_destroy_credcache(&unix_auth); 2229499b434STrond Myklebust } 2239499b434STrond Myklebust 224f1c0a861STrond Myklebust const struct rpc_authops authunix_ops = { 2251da177e4SLinus Torvalds .owner = THIS_MODULE, 2261da177e4SLinus Torvalds .au_flavor = RPC_AUTH_UNIX, 2271da177e4SLinus Torvalds .au_name = "UNIX", 2281da177e4SLinus Torvalds .create = unx_create, 2291da177e4SLinus Torvalds .destroy = unx_destroy, 2301e035d06SFrank Sorenson .hash_cred = unx_hash_cred, 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 = { 2374500632fSChuck Lever .au_cslack = UNX_CALLSLACK, 2384500632fSChuck Lever .au_rslack = NUL_REPLYSLACK, 239ce52914eSScott Mayhew .au_flags = RPCAUTH_AUTH_NO_CRKEY_TIMEOUT, 2401da177e4SLinus Torvalds .au_ops = &authunix_ops, 24181039f1fSTrond Myklebust .au_flavor = RPC_AUTH_UNIX, 2421da177e4SLinus Torvalds .au_count = ATOMIC_INIT(0), 2431da177e4SLinus Torvalds }; 2441da177e4SLinus Torvalds 2451da177e4SLinus Torvalds static 246f1c0a861STrond Myklebust const struct rpc_credops unix_credops = { 2471da177e4SLinus Torvalds .cr_name = "AUTH_UNIX", 2481da177e4SLinus Torvalds .crdestroy = unx_destroy_cred, 2495c691044STrond Myklebust .crbind = rpcauth_generic_bind_cred, 2501da177e4SLinus Torvalds .crmatch = unx_match, 2511da177e4SLinus Torvalds .crmarshal = unx_marshal, 2521da177e4SLinus Torvalds .crrefresh = unx_refresh, 2531da177e4SLinus Torvalds .crvalidate = unx_validate, 2541da177e4SLinus Torvalds }; 255