From 0733d21338747483985a5964e852af160d88e429 Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Fri, 3 Apr 2009 08:28:01 +0300 Subject: nfsd41: exchange_id operation Implement the exchange_id operation confoming to http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-28 Based on the client provided name, hash a client id. If a confirmed one is found, compare the op's creds and verifier. If the creds match and the verifier is different then expire the old client (client re-incarnated), otherwise, if both match, assume it's a replay and ignore it. If an unconfirmed client is found, then copy the new creds and verifer if need update, otherwise assume replay. The client is moved to a confirmed state on create_session. In the nfs41 branch set the exchange_id flags to EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_SUPP_MOVED_REFER (pNFS is not supported, Referrals are supported, Migration is not.). Address various scenarios from section 18.35 of the spec: 1. Check for EXCHGID4_FLAG_UPD_CONFIRMED_REC_A and set EXCHGID4_FLAG_CONFIRMED_R as appropriate. 2. Return error codes per 18.35.4 scenarios. 3. Update client records or generate new client ids depending on scenario. Note: 18.35.4 case 3 probably still needs revisiting. The handling seems not quite right. Signed-off-by: Benny Halevy Signed-off-by: Andy Adamosn Signed-off-by: Benny Halevy [nfsd41: use utsname for major_id (and copy to server_scope)] [nfsd41: fix handling of various exchange id scenarios] Signed-off-by: Mike Sager Signed-off-by: Benny Halevy [nfsd41: reverse use of EXCHGID4_INVAL_FLAG_MASK_A] [simplify nfsd4_encode_exchange_id error handling] [nfsd41: embed an xdr_netobj in nfsd4_exchange_id] [nfsd41: return nfserr_serverfault for spa_how == SP4_MACH_CRED] Signed-off-by: Benny Halevy Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 142 +++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 141 insertions(+), 1 deletion(-) (limited to 'fs/nfsd/nfs4state.c') diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index cfc01f415d15..4f963e902972 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -832,12 +832,152 @@ out_err: return; } +/* + * Set the exchange_id flags returned by the server. + */ +static void +nfsd4_set_ex_flags(struct nfs4_client *new, struct nfsd4_exchange_id *clid) +{ + /* pNFS is not supported */ + new->cl_exchange_flags |= EXCHGID4_FLAG_USE_NON_PNFS; + + /* Referrals are supported, Migration is not. */ + new->cl_exchange_flags |= EXCHGID4_FLAG_SUPP_MOVED_REFER; + + /* set the wire flags to return to client. */ + clid->flags = new->cl_exchange_flags; +} + __be32 nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, struct nfsd4_exchange_id *exid) { - return -1; /* stub */ + struct nfs4_client *unconf, *conf, *new; + int status; + unsigned int strhashval; + char dname[HEXDIR_LEN]; + nfs4_verifier verf = exid->verifier; + u32 ip_addr = svc_addr_in(rqstp)->sin_addr.s_addr; + + dprintk("%s rqstp=%p exid=%p clname.len=%u clname.data=%p " + " ip_addr=%u flags %x, spa_how %d\n", + __func__, rqstp, exid, exid->clname.len, exid->clname.data, + ip_addr, exid->flags, exid->spa_how); + + if (!check_name(exid->clname) || (exid->flags & ~EXCHGID4_FLAG_MASK_A)) + return nfserr_inval; + + /* Currently only support SP4_NONE */ + switch (exid->spa_how) { + case SP4_NONE: + break; + case SP4_SSV: + return nfserr_encr_alg_unsupp; + default: + BUG(); /* checked by xdr code */ + case SP4_MACH_CRED: + return nfserr_serverfault; /* no excuse :-/ */ + } + + status = nfs4_make_rec_clidname(dname, &exid->clname); + + if (status) + goto error; + + strhashval = clientstr_hashval(dname); + + nfs4_lock_state(); + status = nfs_ok; + + conf = find_confirmed_client_by_str(dname, strhashval); + if (conf) { + if (!same_verf(&verf, &conf->cl_verifier)) { + /* 18.35.4 case 8 */ + if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) { + status = nfserr_not_same; + goto out; + } + /* Client reboot: destroy old state */ + expire_client(conf); + goto out_new; + } + if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) { + /* 18.35.4 case 9 */ + if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) { + status = nfserr_perm; + goto out; + } + expire_client(conf); + goto out_new; + } + if (ip_addr != conf->cl_addr && + !(exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A)) { + /* Client collision. 18.35.4 case 3 */ + status = nfserr_clid_inuse; + goto out; + } + /* + * Set bit when the owner id and verifier map to an already + * confirmed client id (18.35.3). + */ + exid->flags |= EXCHGID4_FLAG_CONFIRMED_R; + + /* + * Falling into 18.35.4 case 2, possible router replay. + * Leave confirmed record intact and return same result. + */ + copy_verf(conf, &verf); + new = conf; + goto out_copy; + } else { + /* 18.35.4 case 7 */ + if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) { + status = nfserr_noent; + goto out; + } + } + + unconf = find_unconfirmed_client_by_str(dname, strhashval); + if (unconf) { + /* + * Possible retry or client restart. Per 18.35.4 case 4, + * a new unconfirmed record should be generated regardless + * of whether any properties have changed. + */ + expire_client(unconf); + } + +out_new: + /* Normal case */ + new = create_client(exid->clname, dname); + if (new == NULL) { + status = nfserr_resource; + goto out; + } + + copy_verf(new, &verf); + copy_cred(&new->cl_cred, &rqstp->rq_cred); + new->cl_addr = ip_addr; + gen_clid(new); + gen_confirm(new); + add_to_unconfirmed(new, strhashval); +out_copy: + exid->clientid.cl_boot = new->cl_clientid.cl_boot; + exid->clientid.cl_id = new->cl_clientid.cl_id; + + new->cl_seqid = exid->seqid = 1; + nfsd4_set_ex_flags(new, exid); + + dprintk("nfsd4_exchange_id seqid %d flags %x\n", + new->cl_seqid, new->cl_exchange_flags); + status = nfs_ok; + +out: + nfs4_unlock_state(); +error: + dprintk("nfsd4_exchange_id returns %d\n", ntohl(status)); + return status; } __be32 -- cgit v1.2.2