| /* |
| * 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 <linux/mutex.h> |
| |
| #include <net/inet_sock.h> |
| |
| #include "nfs4_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 DEFINE_MUTEX(nfs_callback_mutex); |
| static struct svc_program nfs4_callback_program; |
| |
| unsigned int nfs_callback_set_tcpport; |
| 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); |
| |
| for(;;) { |
| if (signalled()) { |
| if (nfs_callback_info.users == 0) |
| break; |
| flush_signals(current); |
| } |
| /* |
| * 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); |
| } |
| |
| svc_exit_thread(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(); |
| mutex_lock(&nfs_callback_mutex); |
| 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, nfs_callback_set_tcpport); |
| 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: |
| mutex_unlock(&nfs_callback_mutex); |
| 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(); |
| mutex_lock(&nfs_callback_mutex); |
| nfs_callback_info.users--; |
| do { |
| if (nfs_callback_info.users != 0 || nfs_callback_info.pid == 0) |
| break; |
| if (kill_proc(nfs_callback_info.pid, SIGKILL, 1) < 0) |
| break; |
| } while (wait_for_completion_timeout(&nfs_callback_info.stopped, 5*HZ) == 0); |
| mutex_unlock(&nfs_callback_mutex); |
| 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 |
| */ |
| 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, |
| }; |