| /* |
| * linux/net/sunrpc/auth_unix.c |
| * |
| * UNIX-style authentication; no AUTH_SHORT support |
| * |
| * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/sched.h> |
| #include <linux/module.h> |
| #include <linux/sunrpc/clnt.h> |
| #include <linux/sunrpc/auth.h> |
| |
| #define NFS_NGROUPS 16 |
| |
| struct unx_cred { |
| struct rpc_cred uc_base; |
| gid_t uc_gid; |
| gid_t uc_gids[NFS_NGROUPS]; |
| }; |
| #define uc_uid uc_base.cr_uid |
| |
| #define UNX_WRITESLACK (21 + (UNX_MAXNODENAME >> 2)) |
| |
| #ifdef RPC_DEBUG |
| # define RPCDBG_FACILITY RPCDBG_AUTH |
| #endif |
| |
| static struct rpc_auth unix_auth; |
| static struct rpc_cred_cache unix_cred_cache; |
| static const struct rpc_credops unix_credops; |
| |
| static struct rpc_auth * |
| unx_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor) |
| { |
| dprintk("RPC: creating UNIX authenticator for client %p\n", |
| clnt); |
| atomic_inc(&unix_auth.au_count); |
| return &unix_auth; |
| } |
| |
| static void |
| unx_destroy(struct rpc_auth *auth) |
| { |
| dprintk("RPC: destroying UNIX authenticator %p\n", auth); |
| rpcauth_clear_credcache(auth->au_credcache); |
| } |
| |
| /* |
| * Lookup AUTH_UNIX creds for current process |
| */ |
| static struct rpc_cred * |
| unx_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) |
| { |
| return rpcauth_lookup_credcache(auth, acred, flags); |
| } |
| |
| static struct rpc_cred * |
| unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags) |
| { |
| struct unx_cred *cred; |
| unsigned int groups = 0; |
| unsigned int i; |
| |
| dprintk("RPC: allocating UNIX cred for uid %d gid %d\n", |
| acred->uid, acred->gid); |
| |
| if (!(cred = kmalloc(sizeof(*cred), GFP_NOFS))) |
| return ERR_PTR(-ENOMEM); |
| |
| rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops); |
| cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE; |
| |
| if (acred->group_info != NULL) |
| groups = acred->group_info->ngroups; |
| if (groups > NFS_NGROUPS) |
| groups = NFS_NGROUPS; |
| |
| cred->uc_gid = acred->gid; |
| for (i = 0; i < groups; i++) |
| cred->uc_gids[i] = GROUP_AT(acred->group_info, i); |
| if (i < NFS_NGROUPS) |
| cred->uc_gids[i] = NOGROUP; |
| |
| return &cred->uc_base; |
| } |
| |
| static void |
| unx_free_cred(struct unx_cred *unx_cred) |
| { |
| dprintk("RPC: unx_free_cred %p\n", unx_cred); |
| kfree(unx_cred); |
| } |
| |
| static void |
| unx_free_cred_callback(struct rcu_head *head) |
| { |
| struct unx_cred *unx_cred = container_of(head, struct unx_cred, uc_base.cr_rcu); |
| unx_free_cred(unx_cred); |
| } |
| |
| static void |
| unx_destroy_cred(struct rpc_cred *cred) |
| { |
| call_rcu(&cred->cr_rcu, unx_free_cred_callback); |
| } |
| |
| /* |
| * Match credentials against current process creds. |
| * The root_override argument takes care of cases where the caller may |
| * request root creds (e.g. for NFS swapping). |
| */ |
| static int |
| unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags) |
| { |
| struct unx_cred *cred = container_of(rcred, struct unx_cred, uc_base); |
| unsigned int groups = 0; |
| unsigned int i; |
| |
| |
| if (cred->uc_uid != acred->uid || cred->uc_gid != acred->gid) |
| return 0; |
| |
| if (acred->group_info != NULL) |
| groups = acred->group_info->ngroups; |
| if (groups > NFS_NGROUPS) |
| groups = NFS_NGROUPS; |
| for (i = 0; i < groups ; i++) |
| if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i)) |
| return 0; |
| if (groups < NFS_NGROUPS && |
| cred->uc_gids[groups] != NOGROUP) |
| return 0; |
| return 1; |
| } |
| |
| /* |
| * Marshal credentials. |
| * Maybe we should keep a cached credential for performance reasons. |
| */ |
| static __be32 * |
| unx_marshal(struct rpc_task *task, __be32 *p) |
| { |
| struct rpc_clnt *clnt = task->tk_client; |
| struct unx_cred *cred = container_of(task->tk_msg.rpc_cred, struct unx_cred, uc_base); |
| __be32 *base, *hold; |
| int i; |
| |
| *p++ = htonl(RPC_AUTH_UNIX); |
| base = p++; |
| *p++ = htonl(jiffies/HZ); |
| |
| /* |
| * Copy the UTS nodename captured when the client was created. |
| */ |
| p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen); |
| |
| *p++ = htonl((u32) cred->uc_uid); |
| *p++ = htonl((u32) cred->uc_gid); |
| hold = p++; |
| for (i = 0; i < 16 && cred->uc_gids[i] != (gid_t) NOGROUP; i++) |
| *p++ = htonl((u32) cred->uc_gids[i]); |
| *hold = htonl(p - hold - 1); /* gid array length */ |
| *base = htonl((p - base - 1) << 2); /* cred length */ |
| |
| *p++ = htonl(RPC_AUTH_NULL); |
| *p++ = htonl(0); |
| |
| return p; |
| } |
| |
| /* |
| * Refresh credentials. This is a no-op for AUTH_UNIX |
| */ |
| static int |
| unx_refresh(struct rpc_task *task) |
| { |
| set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_msg.rpc_cred->cr_flags); |
| return 0; |
| } |
| |
| static __be32 * |
| unx_validate(struct rpc_task *task, __be32 *p) |
| { |
| rpc_authflavor_t flavor; |
| u32 size; |
| |
| flavor = ntohl(*p++); |
| if (flavor != RPC_AUTH_NULL && |
| flavor != RPC_AUTH_UNIX && |
| flavor != RPC_AUTH_SHORT) { |
| printk("RPC: bad verf flavor: %u\n", flavor); |
| return NULL; |
| } |
| |
| size = ntohl(*p++); |
| if (size > RPC_MAX_AUTH_SIZE) { |
| printk("RPC: giant verf size: %u\n", size); |
| return NULL; |
| } |
| task->tk_msg.rpc_cred->cr_auth->au_rslack = (size >> 2) + 2; |
| p += (size >> 2); |
| |
| return p; |
| } |
| |
| void __init rpc_init_authunix(void) |
| { |
| spin_lock_init(&unix_cred_cache.lock); |
| } |
| |
| const struct rpc_authops authunix_ops = { |
| .owner = THIS_MODULE, |
| .au_flavor = RPC_AUTH_UNIX, |
| .au_name = "UNIX", |
| .create = unx_create, |
| .destroy = unx_destroy, |
| .lookup_cred = unx_lookup_cred, |
| .crcreate = unx_create_cred, |
| }; |
| |
| static |
| struct rpc_cred_cache unix_cred_cache = { |
| }; |
| |
| static |
| struct rpc_auth unix_auth = { |
| .au_cslack = UNX_WRITESLACK, |
| .au_rslack = 2, /* assume AUTH_NULL verf */ |
| .au_ops = &authunix_ops, |
| .au_flavor = RPC_AUTH_UNIX, |
| .au_count = ATOMIC_INIT(0), |
| .au_credcache = &unix_cred_cache, |
| }; |
| |
| static |
| const struct rpc_credops unix_credops = { |
| .cr_name = "AUTH_UNIX", |
| .crdestroy = unx_destroy_cred, |
| .crbind = rpcauth_generic_bind_cred, |
| .crmatch = unx_match, |
| .crmarshal = unx_marshal, |
| .crrefresh = unx_refresh, |
| .crvalidate = unx_validate, |
| }; |