diff options
Diffstat (limited to 'fs/nfs/callback.c')
| -rw-r--r-- | fs/nfs/callback.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c new file mode 100644 index 00000000000..560d6175dd5 --- /dev/null +++ b/fs/nfs/callback.c @@ -0,0 +1,187 @@ +/* + * linux/fs/nfs/callback.c + * + * Copyright (C) 2004 Trond Myklebust + * + * NFSv4 callback handling + */ + +#include <linux/config.h> +#include <linux/completion.h> +#include <linux/ip.h> +#include <linux/module.h> +#include <linux/smp_lock.h> +#include <linux/sunrpc/svc.h> +#include <linux/sunrpc/svcsock.h> +#include <linux/nfs_fs.h> +#include "callback.h" + +#define NFSDBG_FACILITY NFSDBG_CALLBACK + +struct nfs_callback_data { + unsigned int users; + struct svc_serv *serv; + pid_t pid; + struct completion started; + struct completion stopped; +}; + +static struct nfs_callback_data nfs_callback_info; +static DECLARE_MUTEX(nfs_callback_sema); +static struct svc_program nfs4_callback_program; + +unsigned short nfs_callback_tcpport; + +/* + * This is the callback kernel thread. + */ +static void nfs_callback_svc(struct svc_rqst *rqstp) +{ + struct svc_serv *serv = rqstp->rq_server; + int err; + + __module_get(THIS_MODULE); + lock_kernel(); + + nfs_callback_info.pid = current->pid; + daemonize("nfsv4-svc"); + /* Process request with signals blocked, but allow SIGKILL. */ + allow_signal(SIGKILL); + + complete(&nfs_callback_info.started); + + while (nfs_callback_info.users != 0 || !signalled()) { + /* + * Listen for a request on the socket + */ + err = svc_recv(serv, rqstp, MAX_SCHEDULE_TIMEOUT); + if (err == -EAGAIN || err == -EINTR) + continue; + if (err < 0) { + printk(KERN_WARNING + "%s: terminating on error %d\n", + __FUNCTION__, -err); + break; + } + dprintk("%s: request from %u.%u.%u.%u\n", __FUNCTION__, + NIPQUAD(rqstp->rq_addr.sin_addr.s_addr)); + svc_process(serv, rqstp); + } + + nfs_callback_info.pid = 0; + complete(&nfs_callback_info.stopped); + unlock_kernel(); + module_put_and_exit(0); +} + +/* + * Bring up the server process if it is not already up. + */ +int nfs_callback_up(void) +{ + struct svc_serv *serv; + struct svc_sock *svsk; + int ret = 0; + + lock_kernel(); + down(&nfs_callback_sema); + if (nfs_callback_info.users++ || nfs_callback_info.pid != 0) + goto out; + init_completion(&nfs_callback_info.started); + init_completion(&nfs_callback_info.stopped); + serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE); + ret = -ENOMEM; + if (!serv) + goto out_err; + /* FIXME: We don't want to register this socket with the portmapper */ + ret = svc_makesock(serv, IPPROTO_TCP, 0); + if (ret < 0) + goto out_destroy; + if (!list_empty(&serv->sv_permsocks)) { + svsk = list_entry(serv->sv_permsocks.next, + struct svc_sock, sk_list); + nfs_callback_tcpport = ntohs(inet_sk(svsk->sk_sk)->sport); + dprintk ("Callback port = 0x%x\n", nfs_callback_tcpport); + } else + BUG(); + ret = svc_create_thread(nfs_callback_svc, serv); + if (ret < 0) + goto out_destroy; + nfs_callback_info.serv = serv; + wait_for_completion(&nfs_callback_info.started); +out: + up(&nfs_callback_sema); + unlock_kernel(); + return ret; +out_destroy: + svc_destroy(serv); +out_err: + nfs_callback_info.users--; + goto out; +} + +/* + * Kill the server process if it is not already up. + */ +int nfs_callback_down(void) +{ + int ret = 0; + + lock_kernel(); + down(&nfs_callback_sema); + if (--nfs_callback_info.users || nfs_callback_info.pid == 0) + goto out; + kill_proc(nfs_callback_info.pid, SIGKILL, 1); + wait_for_completion(&nfs_callback_info.stopped); +out: + up(&nfs_callback_sema); + unlock_kernel(); + return ret; +} + +static int nfs_callback_authenticate(struct svc_rqst *rqstp) +{ + struct in_addr *addr = &rqstp->rq_addr.sin_addr; + struct nfs4_client *clp; + + /* Don't talk to strangers */ + clp = nfs4_find_client(addr); + if (clp == NULL) + return SVC_DROP; + dprintk("%s: %u.%u.%u.%u NFSv4 callback!\n", __FUNCTION__, NIPQUAD(addr)); + nfs4_put_client(clp); + switch (rqstp->rq_authop->flavour) { + case RPC_AUTH_NULL: + if (rqstp->rq_proc != CB_NULL) + return SVC_DENIED; + break; + case RPC_AUTH_UNIX: + break; + case RPC_AUTH_GSS: + /* FIXME: RPCSEC_GSS handling? */ + default: + return SVC_DENIED; + } + return SVC_OK; +} + +/* + * Define NFS4 callback program + */ +extern struct svc_version nfs4_callback_version1; + +static struct svc_version *nfs4_callback_version[] = { + [1] = &nfs4_callback_version1, +}; + +static struct svc_stat nfs4_callback_stats; + +static struct svc_program nfs4_callback_program = { + .pg_prog = NFS4_CALLBACK, /* RPC service number */ + .pg_nvers = ARRAY_SIZE(nfs4_callback_version), /* Number of entries */ + .pg_vers = nfs4_callback_version, /* version table */ + .pg_name = "NFSv4 callback", /* service name */ + .pg_class = "nfs", /* authentication class */ + .pg_stats = &nfs4_callback_stats, + .pg_authenticate = nfs_callback_authenticate, +}; |