diff options
Diffstat (limited to 'net/sunrpc/auth_unix.c')
-rw-r--r-- | net/sunrpc/auth_unix.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c new file mode 100644 index 00000000000..4ff297a9b15 --- /dev/null +++ b/net/sunrpc/auth_unix.c @@ -0,0 +1,242 @@ +/* + * 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/socket.h> +#include <linux/in.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 uc_count uc_base.cr_count +#define uc_flags uc_base.cr_flags +#define uc_expire uc_base.cr_expire + +#define UNX_CRED_EXPIRE (60 * HZ) + +#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 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); + if (atomic_inc_return(&unix_auth.au_count) == 0) + unix_cred_cache.nextgc = jiffies + (unix_cred_cache.expire >> 1); + return &unix_auth; +} + +static void +unx_destroy(struct rpc_auth *auth) +{ + dprintk("RPC: destroying UNIX authenticator %p\n", auth); + rpcauth_free_credcache(auth); +} + +/* + * 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; + int i; + + dprintk("RPC: allocating UNIX cred for uid %d gid %d\n", + acred->uid, acred->gid); + + if (!(cred = (struct unx_cred *) kmalloc(sizeof(*cred), GFP_KERNEL))) + return ERR_PTR(-ENOMEM); + + atomic_set(&cred->uc_count, 1); + cred->uc_flags = RPCAUTH_CRED_UPTODATE; + if (flags & RPC_TASK_ROOTCREDS) { + cred->uc_uid = 0; + cred->uc_gid = 0; + cred->uc_gids[0] = NOGROUP; + } else { + int groups = acred->group_info->ngroups; + if (groups > NFS_NGROUPS) + groups = NFS_NGROUPS; + + cred->uc_uid = acred->uid; + 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; + } + cred->uc_base.cr_ops = &unix_credops; + + return (struct rpc_cred *) cred; +} + +static void +unx_destroy_cred(struct rpc_cred *cred) +{ + kfree(cred); +} + +/* + * 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 taskflags) +{ + struct unx_cred *cred = (struct unx_cred *) rcred; + int i; + + if (!(taskflags & RPC_TASK_ROOTCREDS)) { + int groups; + + if (cred->uc_uid != acred->uid + || cred->uc_gid != acred->gid) + return 0; + + 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; + return 1; + } + return (cred->uc_uid == 0 + && cred->uc_gid == 0 + && cred->uc_gids[0] == (gid_t) NOGROUP); +} + +/* + * Marshal credentials. + * Maybe we should keep a cached credential for performance reasons. + */ +static u32 * +unx_marshal(struct rpc_task *task, u32 *p) +{ + struct rpc_clnt *clnt = task->tk_client; + struct unx_cred *cred = (struct unx_cred *) task->tk_msg.rpc_cred; + u32 *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) +{ + task->tk_msg.rpc_cred->cr_flags |= RPCAUTH_CRED_UPTODATE; + return 0; +} + +static u32 * +unx_validate(struct rpc_task *task, u32 *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_auth->au_rslack = (size >> 2) + 2; + p += (size >> 2); + + return p; +} + +struct rpc_authops authunix_ops = { + .owner = THIS_MODULE, + .au_flavor = RPC_AUTH_UNIX, +#ifdef RPC_DEBUG + .au_name = "UNIX", +#endif + .create = unx_create, + .destroy = unx_destroy, + .lookup_cred = unx_lookup_cred, + .crcreate = unx_create_cred, +}; + +static +struct rpc_cred_cache unix_cred_cache = { + .expire = UNX_CRED_EXPIRE, +}; + +static +struct rpc_auth unix_auth = { + .au_cslack = UNX_WRITESLACK, + .au_rslack = 2, /* assume AUTH_NULL verf */ + .au_ops = &authunix_ops, + .au_count = ATOMIC_INIT(0), + .au_credcache = &unix_cred_cache, +}; + +static +struct rpc_credops unix_credops = { + .cr_name = "AUTH_UNIX", + .crdestroy = unx_destroy_cred, + .crmatch = unx_match, + .crmarshal = unx_marshal, + .crrefresh = unx_refresh, + .crvalidate = unx_validate, +}; |