1/*
  2 * linux/net/sunrpc/auth_unix.c
  3 *
  4 * UNIX-style authentication; no AUTH_SHORT support
  5 *
  6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
  7 */
  8
  9#include <linux/slab.h>
 10#include <linux/types.h>
 11#include <linux/sched.h>
 12#include <linux/module.h>
 13#include <linux/sunrpc/clnt.h>
 14#include <linux/sunrpc/auth.h>
 15#include <linux/user_namespace.h>
 16
 17#define NFS_NGROUPS	16
 18
 19struct unx_cred {
 20	struct rpc_cred		uc_base;
 21	gid_t			uc_gid;
 22	gid_t			uc_gids[NFS_NGROUPS];
 23};
 24#define uc_uid			uc_base.cr_uid
 25
 26#define UNX_WRITESLACK		(21 + (UNX_MAXNODENAME >> 2))
 27
 28#ifdef RPC_DEBUG
 29# define RPCDBG_FACILITY	RPCDBG_AUTH
 30#endif
 31
 32static struct rpc_auth		unix_auth;
 33static const struct rpc_credops	unix_credops;
 34
 35static struct rpc_auth *
 36unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
 37{
 38	dprintk("RPC:       creating UNIX authenticator for client %p\n",
 39			clnt);
 40	atomic_inc(&unix_auth.au_count);
 41	return &unix_auth;
 42}
 43
 44static void
 45unx_destroy(struct rpc_auth *auth)
 46{
 47	dprintk("RPC:       destroying UNIX authenticator %p\n", auth);
 48	rpcauth_clear_credcache(auth->au_credcache);
 49}
 50
 
 
 
 
 
 
 
 
 51/*
 52 * Lookup AUTH_UNIX creds for current process
 53 */
 54static struct rpc_cred *
 55unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 56{
 57	return rpcauth_lookup_credcache(auth, acred, flags);
 58}
 59
 60static struct rpc_cred *
 61unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 62{
 63	struct unx_cred	*cred;
 64	unsigned int groups = 0;
 65	unsigned int i;
 66
 67	dprintk("RPC:       allocating UNIX cred for uid %d gid %d\n",
 68			acred->uid, acred->gid);
 
 69
 70	if (!(cred = kmalloc(sizeof(*cred), GFP_NOFS)))
 71		return ERR_PTR(-ENOMEM);
 72
 73	rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops);
 74	cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
 75
 76	if (acred->group_info != NULL)
 77		groups = acred->group_info->ngroups;
 78	if (groups > NFS_NGROUPS)
 79		groups = NFS_NGROUPS;
 80
 81	cred->uc_gid = acred->gid;
 82	for (i = 0; i < groups; i++) {
 83		gid_t gid;
 84		gid = from_kgid(&init_user_ns, GROUP_AT(acred->group_info, i));
 85		cred->uc_gids[i] = gid;
 86	}
 87	if (i < NFS_NGROUPS)
 88		cred->uc_gids[i] = NOGROUP;
 89
 90	return &cred->uc_base;
 91}
 92
 93static void
 94unx_free_cred(struct unx_cred *unx_cred)
 95{
 96	dprintk("RPC:       unx_free_cred %p\n", unx_cred);
 97	kfree(unx_cred);
 98}
 99
100static void
101unx_free_cred_callback(struct rcu_head *head)
102{
103	struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu);
104	unx_free_cred(unx_cred);
105}
106
107static void
108unx_destroy_cred(struct rpc_cred *cred)
109{
110	call_rcu(&cred->cr_rcu, unx_free_cred_callback);
111}
112
113/*
114 * Match credentials against current process creds.
115 * The root_override argument takes care of cases where the caller may
116 * request root creds (e.g. for NFS swapping).
117 */
118static int
119unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
120{
121	struct unx_cred	*cred = container_of(rcred, struct unx_cred, uc_base);
122	unsigned int groups = 0;
123	unsigned int i;
124
125
126	if (cred->uc_uid != acred->uid || cred->uc_gid != acred->gid)
127		return 0;
128
129	if (acred->group_info != NULL)
130		groups = acred->group_info->ngroups;
131	if (groups > NFS_NGROUPS)
132		groups = NFS_NGROUPS;
133	for (i = 0; i < groups ; i++) {
134		gid_t gid;
135		gid = from_kgid(&init_user_ns, GROUP_AT(acred->group_info, i));
136		if (cred->uc_gids[i] != gid)
137			return 0;
138	}
139	if (groups < NFS_NGROUPS &&
140	    cred->uc_gids[groups] != NOGROUP)
141		return 0;
142	return 1;
143}
144
145/*
146 * Marshal credentials.
147 * Maybe we should keep a cached credential for performance reasons.
148 */
149static __be32 *
150unx_marshal(struct rpc_task *task, __be32 *p)
151{
152	struct rpc_clnt	*clnt = task->tk_client;
153	struct unx_cred	*cred = container_of(task->tk_rqstp->rq_cred, struct unx_cred, uc_base);
154	__be32		*base, *hold;
155	int		i;
156
157	*p++ = htonl(RPC_AUTH_UNIX);
158	base = p++;
159	*p++ = htonl(jiffies/HZ);
160
161	/*
162	 * Copy the UTS nodename captured when the client was created.
163	 */
164	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
165
166	*p++ = htonl((u32) cred->uc_uid);
167	*p++ = htonl((u32) cred->uc_gid);
168	hold = p++;
169	for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++)
170		*p++ = htonl((u32) cred->uc_gids[i]);
171	*hold = htonl(p - hold - 1);		/* gid array length */
172	*base = htonl((p - base - 1) << 2);	/* cred length */
173
174	*p++ = htonl(RPC_AUTH_NULL);
175	*p++ = htonl(0);
176
177	return p;
178}
179
180/*
181 * Refresh credentials. This is a no-op for AUTH_UNIX
182 */
183static int
184unx_refresh(struct rpc_task *task)
185{
186	set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
187	return 0;
188}
189
190static __be32 *
191unx_validate(struct rpc_task *task, __be32 *p)
192{
193	rpc_authflavor_t	flavor;
194	u32			size;
195
196	flavor = ntohl(*p++);
197	if (flavor != RPC_AUTH_NULL &&
198	    flavor != RPC_AUTH_UNIX &&
199	    flavor != RPC_AUTH_SHORT) {
200		printk("RPC: bad verf flavor: %u\n", flavor);
201		return NULL;
202	}
203
204	size = ntohl(*p++);
205	if (size > RPC_MAX_AUTH_SIZE) {
206		printk("RPC: giant verf size: %u\n", size);
207		return NULL;
208	}
209	task->tk_rqstp->rq_cred->cr_auth->au_rslack = (size >> 2) + 2;
210	p += (size >> 2);
211
212	return p;
213}
214
215int __init rpc_init_authunix(void)
216{
217	return rpcauth_init_credcache(&unix_auth);
218}
219
220void rpc_destroy_authunix(void)
221{
222	rpcauth_destroy_credcache(&unix_auth);
223}
224
225const struct rpc_authops authunix_ops = {
226	.owner		= THIS_MODULE,
227	.au_flavor	= RPC_AUTH_UNIX,
228	.au_name	= "UNIX",
229	.create		= unx_create,
230	.destroy	= unx_destroy,
 
231	.lookup_cred	= unx_lookup_cred,
232	.crcreate	= unx_create_cred,
233};
234
235static
236struct rpc_auth		unix_auth = {
237	.au_cslack	= UNX_WRITESLACK,
238	.au_rslack	= 2,			/* assume AUTH_NULL verf */
 
239	.au_ops		= &authunix_ops,
240	.au_flavor	= RPC_AUTH_UNIX,
241	.au_count	= ATOMIC_INIT(0),
242};
243
244static
245const struct rpc_credops unix_credops = {
246	.cr_name	= "AUTH_UNIX",
247	.crdestroy	= unx_destroy_cred,
248	.crbind		= rpcauth_generic_bind_cred,
249	.crmatch	= unx_match,
250	.crmarshal	= unx_marshal,
251	.crrefresh	= unx_refresh,
252	.crvalidate	= unx_validate,
253};

  1/*
  2 * linux/net/sunrpc/auth_unix.c
  3 *
  4 * UNIX-style authentication; no AUTH_SHORT support
  5 *
  6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
  7 */
  8
  9#include <linux/slab.h>
 10#include <linux/types.h>
 11#include <linux/sched.h>
 12#include <linux/module.h>
 13#include <linux/sunrpc/clnt.h>
 14#include <linux/sunrpc/auth.h>
 15#include <linux/user_namespace.h>
 16
 17#define NFS_NGROUPS	16
 18
 19struct unx_cred {
 20	struct rpc_cred		uc_base;
 21	kgid_t			uc_gid;
 22	kgid_t			uc_gids[NFS_NGROUPS];
 23};
 24#define uc_uid			uc_base.cr_uid
 25
 26#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 
 
 27# define RPCDBG_FACILITY	RPCDBG_AUTH
 28#endif
 29
 30static struct rpc_auth		unix_auth;
 31static const struct rpc_credops	unix_credops;
 32
 33static struct rpc_auth *
 34unx_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 35{
 36	dprintk("RPC:       creating UNIX authenticator for client %p\n",
 37			clnt);
 38	atomic_inc(&unix_auth.au_count);
 39	return &unix_auth;
 40}
 41
 42static void
 43unx_destroy(struct rpc_auth *auth)
 44{
 45	dprintk("RPC:       destroying UNIX authenticator %p\n", auth);
 46	rpcauth_clear_credcache(auth->au_credcache);
 47}
 48
 49static int
 50unx_hash_cred(struct auth_cred *acred, unsigned int hashbits)
 51{
 52	return hash_64(from_kgid(&init_user_ns, acred->gid) |
 53		((u64)from_kuid(&init_user_ns, acred->uid) <<
 54			(sizeof(gid_t) * 8)), hashbits);
 55}
 56
 57/*
 58 * Lookup AUTH_UNIX creds for current process
 59 */
 60static struct rpc_cred *
 61unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 62{
 63	return rpcauth_lookup_credcache(auth, acred, flags, GFP_NOFS);
 64}
 65
 66static struct rpc_cred *
 67unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags, gfp_t gfp)
 68{
 69	struct unx_cred	*cred;
 70	unsigned int groups = 0;
 71	unsigned int i;
 72
 73	dprintk("RPC:       allocating UNIX cred for uid %d gid %d\n",
 74			from_kuid(&init_user_ns, acred->uid),
 75			from_kgid(&init_user_ns, acred->gid));
 76
 77	if (!(cred = kmalloc(sizeof(*cred), gfp)))
 78		return ERR_PTR(-ENOMEM);
 79
 80	rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops);
 81	cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
 82
 83	if (acred->group_info != NULL)
 84		groups = acred->group_info->ngroups;
 85	if (groups > NFS_NGROUPS)
 86		groups = NFS_NGROUPS;
 87
 88	cred->uc_gid = acred->gid;
 89	for (i = 0; i < groups; i++)
 90		cred->uc_gids[i] = acred->group_info->gid[i];
 
 
 
 91	if (i < NFS_NGROUPS)
 92		cred->uc_gids[i] = INVALID_GID;
 93
 94	return &cred->uc_base;
 95}
 96
 97static void
 98unx_free_cred(struct unx_cred *unx_cred)
 99{
100	dprintk("RPC:       unx_free_cred %p\n", unx_cred);
101	kfree(unx_cred);
102}
103
104static void
105unx_free_cred_callback(struct rcu_head *head)
106{
107	struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu);
108	unx_free_cred(unx_cred);
109}
110
111static void
112unx_destroy_cred(struct rpc_cred *cred)
113{
114	call_rcu(&cred->cr_rcu, unx_free_cred_callback);
115}
116
117/*
118 * Match credentials against current process creds.
119 * The root_override argument takes care of cases where the caller may
120 * request root creds (e.g. for NFS swapping).
121 */
122static int
123unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
124{
125	struct unx_cred	*cred = container_of(rcred, struct unx_cred, uc_base);
126	unsigned int groups = 0;
127	unsigned int i;
128
129
130	if (!uid_eq(cred->uc_uid, acred->uid) || !gid_eq(cred->uc_gid, acred->gid))
131		return 0;
132
133	if (acred->group_info != NULL)
134		groups = acred->group_info->ngroups;
135	if (groups > NFS_NGROUPS)
136		groups = NFS_NGROUPS;
137	for (i = 0; i < groups ; i++)
138		if (!gid_eq(cred->uc_gids[i], acred->group_info->gid[i]))
 
 
139			return 0;
140	if (groups < NFS_NGROUPS && gid_valid(cred->uc_gids[groups]))
 
 
141		return 0;
142	return 1;
143}
144
145/*
146 * Marshal credentials.
147 * Maybe we should keep a cached credential for performance reasons.
148 */
149static __be32 *
150unx_marshal(struct rpc_task *task, __be32 *p)
151{
152	struct rpc_clnt	*clnt = task->tk_client;
153	struct unx_cred	*cred = container_of(task->tk_rqstp->rq_cred, struct unx_cred, uc_base);
154	__be32		*base, *hold;
155	int		i;
156
157	*p++ = htonl(RPC_AUTH_UNIX);
158	base = p++;
159	*p++ = htonl(jiffies/HZ);
160
161	/*
162	 * Copy the UTS nodename captured when the client was created.
163	 */
164	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
165
166	*p++ = htonl((u32) from_kuid(&init_user_ns, cred->uc_uid));
167	*p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gid));
168	hold = p++;
169	for (i = 0; i < 16 && gid_valid(cred->uc_gids[i]); i++)
170		*p++ = htonl((u32) from_kgid(&init_user_ns, cred->uc_gids[i]));
171	*hold = htonl(p - hold - 1);		/* gid array length */
172	*base = htonl((p - base - 1) << 2);	/* cred length */
173
174	*p++ = htonl(RPC_AUTH_NULL);
175	*p++ = htonl(0);
176
177	return p;
178}
179
180/*
181 * Refresh credentials. This is a no-op for AUTH_UNIX
182 */
183static int
184unx_refresh(struct rpc_task *task)
185{
186	set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
187	return 0;
188}
189
190static __be32 *
191unx_validate(struct rpc_task *task, __be32 *p)
192{
193	rpc_authflavor_t	flavor;
194	u32			size;
195
196	flavor = ntohl(*p++);
197	if (flavor != RPC_AUTH_NULL &&
198	    flavor != RPC_AUTH_UNIX &&
199	    flavor != RPC_AUTH_SHORT) {
200		printk("RPC: bad verf flavor: %u\n", flavor);
201		return ERR_PTR(-EIO);
202	}
203
204	size = ntohl(*p++);
205	if (size > RPC_MAX_AUTH_SIZE) {
206		printk("RPC: giant verf size: %u\n", size);
207		return ERR_PTR(-EIO);
208	}
209	task->tk_rqstp->rq_cred->cr_auth->au_rslack = (size >> 2) + 2;
210	p += (size >> 2);
211
212	return p;
213}
214
215int __init rpc_init_authunix(void)
216{
217	return rpcauth_init_credcache(&unix_auth);
218}
219
220void rpc_destroy_authunix(void)
221{
222	rpcauth_destroy_credcache(&unix_auth);
223}
224
225const struct rpc_authops authunix_ops = {
226	.owner		= THIS_MODULE,
227	.au_flavor	= RPC_AUTH_UNIX,
228	.au_name	= "UNIX",
229	.create		= unx_create,
230	.destroy	= unx_destroy,
231	.hash_cred	= unx_hash_cred,
232	.lookup_cred	= unx_lookup_cred,
233	.crcreate	= unx_create_cred,
234};
235
236static
237struct rpc_auth		unix_auth = {
238	.au_cslack	= UNX_CALLSLACK,
239	.au_rslack	= NUL_REPLYSLACK,
240	.au_flags	= RPCAUTH_AUTH_NO_CRKEY_TIMEOUT,
241	.au_ops		= &authunix_ops,
242	.au_flavor	= RPC_AUTH_UNIX,
243	.au_count	= ATOMIC_INIT(0),
244};
245
246static
247const struct rpc_credops unix_credops = {
248	.cr_name	= "AUTH_UNIX",
249	.crdestroy	= unx_destroy_cred,
250	.crbind		= rpcauth_generic_bind_cred,
251	.crmatch	= unx_match,
252	.crmarshal	= unx_marshal,
253	.crrefresh	= unx_refresh,
254	.crvalidate	= unx_validate,
255};