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Current File : //compat/linux/proc/self/root/usr/src/sys/netsmb/smb_rq.c |
/*- * Copyright (c) 2000-2001 Boris Popov * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/cdefs.h> __FBSDID("$FreeBSD: release/9.1.0/sys/netsmb/smb_rq.c 206361 2010-04-07 16:50:38Z joel $"); #include <sys/param.h> #include <sys/systm.h> #include <sys/endian.h> #include <sys/kernel.h> #include <sys/malloc.h> #include <sys/module.h> #include <sys/proc.h> #include <sys/lock.h> #include <sys/sysctl.h> #include <sys/socket.h> #include <sys/socketvar.h> #include <sys/mbuf.h> #include <netsmb/smb.h> #include <netsmb/smb_conn.h> #include <netsmb/smb_rq.h> #include <netsmb/smb_subr.h> #include <netsmb/smb_tran.h> MALLOC_DEFINE(M_SMBRQ, "SMBRQ", "SMB request"); MODULE_DEPEND(netsmb, libmchain, 1, 1, 1); static int smb_rq_reply(struct smb_rq *rqp); static int smb_rq_enqueue(struct smb_rq *rqp); static int smb_rq_getenv(struct smb_connobj *layer, struct smb_vc **vcpp, struct smb_share **sspp); static int smb_rq_new(struct smb_rq *rqp, u_char cmd); static int smb_t2_reply(struct smb_t2rq *t2p); int smb_rq_alloc(struct smb_connobj *layer, u_char cmd, struct smb_cred *scred, struct smb_rq **rqpp) { struct smb_rq *rqp; int error; rqp = malloc(sizeof(*rqp), M_SMBRQ, M_WAITOK); if (rqp == NULL) return ENOMEM; error = smb_rq_init(rqp, layer, cmd, scred); rqp->sr_flags |= SMBR_ALLOCED; if (error) { smb_rq_done(rqp); return error; } *rqpp = rqp; return 0; } static char tzero[12]; int smb_rq_init(struct smb_rq *rqp, struct smb_connobj *layer, u_char cmd, struct smb_cred *scred) { int error; bzero(rqp, sizeof(*rqp)); smb_sl_init(&rqp->sr_slock, "srslock"); error = smb_rq_getenv(layer, &rqp->sr_vc, &rqp->sr_share); if (error) return error; error = smb_vc_access(rqp->sr_vc, scred, SMBM_EXEC); if (error) return error; if (rqp->sr_share) { error = smb_share_access(rqp->sr_share, scred, SMBM_EXEC); if (error) return error; } rqp->sr_cred = scred; rqp->sr_mid = smb_vc_nextmid(rqp->sr_vc); return smb_rq_new(rqp, cmd); } static int smb_rq_new(struct smb_rq *rqp, u_char cmd) { struct smb_vc *vcp = rqp->sr_vc; struct mbchain *mbp = &rqp->sr_rq; int error; u_int16_t flags2; rqp->sr_sendcnt = 0; mb_done(mbp); md_done(&rqp->sr_rp); error = mb_init(mbp); if (error) return error; mb_put_mem(mbp, SMB_SIGNATURE, SMB_SIGLEN, MB_MSYSTEM); mb_put_uint8(mbp, cmd); mb_put_uint32le(mbp, 0); /* DosError */ mb_put_uint8(mbp, vcp->vc_hflags); flags2 = vcp->vc_hflags2; if (cmd == SMB_COM_TRANSACTION || cmd == SMB_COM_TRANSACTION_SECONDARY) flags2 &= ~SMB_FLAGS2_UNICODE; if (cmd == SMB_COM_NEGOTIATE) flags2 &= ~SMB_FLAGS2_SECURITY_SIGNATURE; mb_put_uint16le(mbp, flags2); if ((flags2 & SMB_FLAGS2_SECURITY_SIGNATURE) == 0) { mb_put_mem(mbp, tzero, 12, MB_MSYSTEM); rqp->sr_rqsig = NULL; } else { mb_put_uint16le(mbp, 0 /*scred->sc_p->p_pid >> 16*/); rqp->sr_rqsig = (u_int8_t *)mb_reserve(mbp, 8); mb_put_uint16le(mbp, 0); } rqp->sr_rqtid = mb_reserve(mbp, sizeof(u_int16_t)); mb_put_uint16le(mbp, 1 /*scred->sc_p->p_pid & 0xffff*/); rqp->sr_rquid = mb_reserve(mbp, sizeof(u_int16_t)); mb_put_uint16le(mbp, rqp->sr_mid); return 0; } void smb_rq_done(struct smb_rq *rqp) { mb_done(&rqp->sr_rq); md_done(&rqp->sr_rp); smb_sl_destroy(&rqp->sr_slock); if (rqp->sr_flags & SMBR_ALLOCED) free(rqp, M_SMBRQ); } /* * Simple request-reply exchange */ int smb_rq_simple(struct smb_rq *rqp) { struct smb_vc *vcp = rqp->sr_vc; int error = EINVAL, i; for (i = 0; i < SMB_MAXRCN; i++) { rqp->sr_flags &= ~SMBR_RESTART; rqp->sr_timo = vcp->vc_timo; rqp->sr_state = SMBRQ_NOTSENT; error = smb_rq_enqueue(rqp); if (error) return error; error = smb_rq_reply(rqp); if (error == 0) break; if ((rqp->sr_flags & (SMBR_RESTART | SMBR_NORESTART)) != SMBR_RESTART) break; } return error; } static int smb_rq_enqueue(struct smb_rq *rqp) { struct smb_share *ssp = rqp->sr_share; int error; if (ssp == NULL || rqp->sr_cred == &rqp->sr_vc->vc_iod->iod_scred) { return smb_iod_addrq(rqp); } for (;;) { SMBS_ST_LOCK(ssp); if (ssp->ss_flags & SMBS_RECONNECTING) { msleep(&ssp->ss_vcgenid, SMBS_ST_LOCKPTR(ssp), PWAIT | PDROP, "90trcn", hz); if (smb_td_intr(rqp->sr_cred->scr_td)) return EINTR; continue; } if (smb_share_valid(ssp) || (ssp->ss_flags & SMBS_CONNECTED) == 0) { SMBS_ST_UNLOCK(ssp); } else { SMBS_ST_UNLOCK(ssp); error = smb_iod_request(rqp->sr_vc->vc_iod, SMBIOD_EV_TREECONNECT | SMBIOD_EV_SYNC, ssp); if (error) return error; } error = smb_iod_addrq(rqp); if (error != EXDEV) break; } return error; } void smb_rq_wstart(struct smb_rq *rqp) { rqp->sr_wcount = mb_reserve(&rqp->sr_rq, sizeof(u_int8_t)); rqp->sr_rq.mb_count = 0; } void smb_rq_wend(struct smb_rq *rqp) { if (rqp->sr_wcount == NULL) { SMBERROR("no wcount\n"); /* actually panic */ return; } if (rqp->sr_rq.mb_count & 1) SMBERROR("odd word count\n"); *rqp->sr_wcount = rqp->sr_rq.mb_count / 2; } void smb_rq_bstart(struct smb_rq *rqp) { rqp->sr_bcount = mb_reserve(&rqp->sr_rq, sizeof(u_short)); rqp->sr_rq.mb_count = 0; } void smb_rq_bend(struct smb_rq *rqp) { int bcnt; if (rqp->sr_bcount == NULL) { SMBERROR("no bcount\n"); /* actually panic */ return; } bcnt = rqp->sr_rq.mb_count; if (bcnt > 0xffff) SMBERROR("byte count too large (%d)\n", bcnt); le16enc(rqp->sr_bcount, bcnt); } int smb_rq_intr(struct smb_rq *rqp) { if (rqp->sr_flags & SMBR_INTR) return EINTR; return smb_td_intr(rqp->sr_cred->scr_td); } int smb_rq_getrequest(struct smb_rq *rqp, struct mbchain **mbpp) { *mbpp = &rqp->sr_rq; return 0; } int smb_rq_getreply(struct smb_rq *rqp, struct mdchain **mbpp) { *mbpp = &rqp->sr_rp; return 0; } static int smb_rq_getenv(struct smb_connobj *layer, struct smb_vc **vcpp, struct smb_share **sspp) { struct smb_vc *vcp = NULL; struct smb_share *ssp = NULL; struct smb_connobj *cp; int error = 0; switch (layer->co_level) { case SMBL_VC: vcp = CPTOVC(layer); if (layer->co_parent == NULL) { SMBERROR("zombie VC %s\n", vcp->vc_srvname); error = EINVAL; break; } break; case SMBL_SHARE: ssp = CPTOSS(layer); cp = layer->co_parent; if (cp == NULL) { SMBERROR("zombie share %s\n", ssp->ss_name); error = EINVAL; break; } error = smb_rq_getenv(cp, &vcp, NULL); if (error) break; break; default: SMBERROR("invalid layer %d passed\n", layer->co_level); error = EINVAL; } if (vcpp) *vcpp = vcp; if (sspp) *sspp = ssp; return error; } /* * Wait for reply on the request */ static int smb_rq_reply(struct smb_rq *rqp) { struct mdchain *mdp = &rqp->sr_rp; u_int32_t tdw; u_int8_t tb; int error, rperror = 0; error = smb_iod_waitrq(rqp); if (error) return error; error = md_get_uint32(mdp, &tdw); if (error) return error; error = md_get_uint8(mdp, &tb); if (rqp->sr_vc->vc_hflags2 & SMB_FLAGS2_ERR_STATUS) { error = md_get_uint32le(mdp, &rqp->sr_error); } else { error = md_get_uint8(mdp, &rqp->sr_errclass); error = md_get_uint8(mdp, &tb); error = md_get_uint16le(mdp, &rqp->sr_serror); if (!error) rperror = smb_maperror(rqp->sr_errclass, rqp->sr_serror); } error = md_get_uint8(mdp, &rqp->sr_rpflags); error = md_get_uint16le(mdp, &rqp->sr_rpflags2); error = md_get_uint32(mdp, &tdw); error = md_get_uint32(mdp, &tdw); error = md_get_uint32(mdp, &tdw); error = md_get_uint16le(mdp, &rqp->sr_rptid); error = md_get_uint16le(mdp, &rqp->sr_rppid); error = md_get_uint16le(mdp, &rqp->sr_rpuid); error = md_get_uint16le(mdp, &rqp->sr_rpmid); if (error == 0 && (rqp->sr_vc->vc_hflags2 & SMB_FLAGS2_SECURITY_SIGNATURE)) error = smb_rq_verify(rqp); SMBSDEBUG("M:%04x, P:%04x, U:%04x, T:%04x, E: %d:%d\n", rqp->sr_rpmid, rqp->sr_rppid, rqp->sr_rpuid, rqp->sr_rptid, rqp->sr_errclass, rqp->sr_serror); return error ? error : rperror; } #define ALIGN4(a) (((a) + 3) & ~3) /* * TRANS2 request implementation */ int smb_t2_alloc(struct smb_connobj *layer, u_short setup, struct smb_cred *scred, struct smb_t2rq **t2pp) { struct smb_t2rq *t2p; int error; t2p = malloc(sizeof(*t2p), M_SMBRQ, M_WAITOK); if (t2p == NULL) return ENOMEM; error = smb_t2_init(t2p, layer, setup, scred); t2p->t2_flags |= SMBT2_ALLOCED; if (error) { smb_t2_done(t2p); return error; } *t2pp = t2p; return 0; } int smb_t2_init(struct smb_t2rq *t2p, struct smb_connobj *source, u_short setup, struct smb_cred *scred) { int error; bzero(t2p, sizeof(*t2p)); t2p->t2_source = source; t2p->t2_setupcount = 1; t2p->t2_setupdata = t2p->t2_setup; t2p->t2_setup[0] = setup; t2p->t2_fid = 0xffff; t2p->t2_cred = scred; error = smb_rq_getenv(source, &t2p->t2_vc, NULL); if (error) return error; return 0; } void smb_t2_done(struct smb_t2rq *t2p) { mb_done(&t2p->t2_tparam); mb_done(&t2p->t2_tdata); md_done(&t2p->t2_rparam); md_done(&t2p->t2_rdata); if (t2p->t2_flags & SMBT2_ALLOCED) free(t2p, M_SMBRQ); } static int smb_t2_placedata(struct mbuf *mtop, u_int16_t offset, u_int16_t count, struct mdchain *mdp) { struct mbuf *m, *m0; int len; m0 = m_split(mtop, offset, M_WAIT); len = m_length(m0, &m); m->m_len -= len - count; if (mdp->md_top == NULL) { md_initm(mdp, m0); } else m_cat(mdp->md_top, m0); return 0; } static int smb_t2_reply(struct smb_t2rq *t2p) { struct mdchain *mdp; struct smb_rq *rqp = t2p->t2_rq; int error, totpgot, totdgot; u_int16_t totpcount, totdcount, pcount, poff, doff, pdisp, ddisp; u_int16_t tmp, bc, dcount; u_int8_t wc; error = smb_rq_reply(rqp); if (error) return error; if ((t2p->t2_flags & SMBT2_ALLSENT) == 0) { /* * this is an interim response, ignore it. */ SMBRQ_SLOCK(rqp); md_next_record(&rqp->sr_rp); SMBRQ_SUNLOCK(rqp); return 0; } /* * Now we have to get all subsequent responses. The CIFS specification * says that they can be disordered which is weird. * TODO: timo */ totpgot = totdgot = 0; totpcount = totdcount = 0xffff; mdp = &rqp->sr_rp; for (;;) { m_dumpm(mdp->md_top); if ((error = md_get_uint8(mdp, &wc)) != 0) break; if (wc < 10) { error = ENOENT; break; } if ((error = md_get_uint16le(mdp, &tmp)) != 0) break; if (totpcount > tmp) totpcount = tmp; md_get_uint16le(mdp, &tmp); if (totdcount > tmp) totdcount = tmp; if ((error = md_get_uint16le(mdp, &tmp)) != 0 || /* reserved */ (error = md_get_uint16le(mdp, &pcount)) != 0 || (error = md_get_uint16le(mdp, &poff)) != 0 || (error = md_get_uint16le(mdp, &pdisp)) != 0) break; if (pcount != 0 && pdisp != totpgot) { SMBERROR("Can't handle disordered parameters %d:%d\n", pdisp, totpgot); error = EINVAL; break; } if ((error = md_get_uint16le(mdp, &dcount)) != 0 || (error = md_get_uint16le(mdp, &doff)) != 0 || (error = md_get_uint16le(mdp, &ddisp)) != 0) break; if (dcount != 0 && ddisp != totdgot) { SMBERROR("Can't handle disordered data\n"); error = EINVAL; break; } md_get_uint8(mdp, &wc); md_get_uint8(mdp, NULL); tmp = wc; while (tmp--) md_get_uint16(mdp, NULL); if ((error = md_get_uint16le(mdp, &bc)) != 0) break; /* tmp = SMB_HDRLEN + 1 + 10 * 2 + 2 * wc + 2;*/ if (dcount) { error = smb_t2_placedata(mdp->md_top, doff, dcount, &t2p->t2_rdata); if (error) break; } if (pcount) { error = smb_t2_placedata(mdp->md_top, poff, pcount, &t2p->t2_rparam); if (error) break; } totpgot += pcount; totdgot += dcount; if (totpgot >= totpcount && totdgot >= totdcount) { error = 0; t2p->t2_flags |= SMBT2_ALLRECV; break; } /* * We're done with this reply, look for the next one. */ SMBRQ_SLOCK(rqp); md_next_record(&rqp->sr_rp); SMBRQ_SUNLOCK(rqp); error = smb_rq_reply(rqp); if (error) break; } return error; } /* * Perform a full round of TRANS2 request */ static int smb_t2_request_int(struct smb_t2rq *t2p) { struct smb_vc *vcp = t2p->t2_vc; struct smb_cred *scred = t2p->t2_cred; struct mbchain *mbp; struct mdchain *mdp, mbparam, mbdata; struct mbuf *m; struct smb_rq *rqp; int totpcount, leftpcount, totdcount, leftdcount, len, txmax, i; int error, doff, poff, txdcount, txpcount, nmlen; m = t2p->t2_tparam.mb_top; if (m) { md_initm(&mbparam, m); /* do not free it! */ totpcount = m_fixhdr(m); if (totpcount > 0xffff) /* maxvalue for u_short */ return EINVAL; } else totpcount = 0; m = t2p->t2_tdata.mb_top; if (m) { md_initm(&mbdata, m); /* do not free it! */ totdcount = m_fixhdr(m); if (totdcount > 0xffff) return EINVAL; } else totdcount = 0; leftdcount = totdcount; leftpcount = totpcount; txmax = vcp->vc_txmax; error = smb_rq_alloc(t2p->t2_source, t2p->t_name ? SMB_COM_TRANSACTION : SMB_COM_TRANSACTION2, scred, &rqp); if (error) return error; rqp->sr_flags |= SMBR_MULTIPACKET; t2p->t2_rq = rqp; rqp->sr_t2 = t2p; mbp = &rqp->sr_rq; smb_rq_wstart(rqp); mb_put_uint16le(mbp, totpcount); mb_put_uint16le(mbp, totdcount); mb_put_uint16le(mbp, t2p->t2_maxpcount); mb_put_uint16le(mbp, t2p->t2_maxdcount); mb_put_uint8(mbp, t2p->t2_maxscount); mb_put_uint8(mbp, 0); /* reserved */ mb_put_uint16le(mbp, 0); /* flags */ mb_put_uint32le(mbp, 0); /* Timeout */ mb_put_uint16le(mbp, 0); /* reserved 2 */ len = mb_fixhdr(mbp); /* * now we have known packet size as * ALIGN4(len + 5 * 2 + setupcount * 2 + 2 + strlen(name) + 1), * and need to decide which parts should go into the first request */ nmlen = t2p->t_name ? strlen(t2p->t_name) : 0; len = ALIGN4(len + 5 * 2 + t2p->t2_setupcount * 2 + 2 + nmlen + 1); if (len + leftpcount > txmax) { txpcount = min(leftpcount, txmax - len); poff = len; txdcount = 0; doff = 0; } else { txpcount = leftpcount; poff = txpcount ? len : 0; len = ALIGN4(len + txpcount); txdcount = min(leftdcount, txmax - len); doff = txdcount ? len : 0; } leftpcount -= txpcount; leftdcount -= txdcount; mb_put_uint16le(mbp, txpcount); mb_put_uint16le(mbp, poff); mb_put_uint16le(mbp, txdcount); mb_put_uint16le(mbp, doff); mb_put_uint8(mbp, t2p->t2_setupcount); mb_put_uint8(mbp, 0); for (i = 0; i < t2p->t2_setupcount; i++) mb_put_uint16le(mbp, t2p->t2_setupdata[i]); smb_rq_wend(rqp); smb_rq_bstart(rqp); /* TDUNICODE */ if (t2p->t_name) mb_put_mem(mbp, t2p->t_name, nmlen, MB_MSYSTEM); mb_put_uint8(mbp, 0); /* terminating zero */ len = mb_fixhdr(mbp); if (txpcount) { mb_put_mem(mbp, NULL, ALIGN4(len) - len, MB_MZERO); error = md_get_mbuf(&mbparam, txpcount, &m); SMBSDEBUG("%d:%d:%d\n", error, txpcount, txmax); if (error) goto freerq; mb_put_mbuf(mbp, m); } len = mb_fixhdr(mbp); if (txdcount) { mb_put_mem(mbp, NULL, ALIGN4(len) - len, MB_MZERO); error = md_get_mbuf(&mbdata, txdcount, &m); if (error) goto freerq; mb_put_mbuf(mbp, m); } smb_rq_bend(rqp); /* incredible, but thats it... */ error = smb_rq_enqueue(rqp); if (error) goto freerq; if (leftpcount == 0 && leftdcount == 0) t2p->t2_flags |= SMBT2_ALLSENT; error = smb_t2_reply(t2p); if (error) goto bad; while (leftpcount || leftdcount) { t2p->t2_flags |= SMBT2_SECONDARY; error = smb_rq_new(rqp, t2p->t_name ? SMB_COM_TRANSACTION_SECONDARY : SMB_COM_TRANSACTION2_SECONDARY); if (error) goto bad; mbp = &rqp->sr_rq; smb_rq_wstart(rqp); mb_put_uint16le(mbp, totpcount); mb_put_uint16le(mbp, totdcount); len = mb_fixhdr(mbp); /* * now we have known packet size as * ALIGN4(len + 7 * 2 + 2) for T2 request, and -2 for T one, * and need to decide which parts should go into request */ len = ALIGN4(len + 6 * 2 + 2); if (t2p->t_name == NULL) len += 2; if (len + leftpcount > txmax) { txpcount = min(leftpcount, txmax - len); poff = len; txdcount = 0; doff = 0; } else { txpcount = leftpcount; poff = txpcount ? len : 0; len = ALIGN4(len + txpcount); txdcount = min(leftdcount, txmax - len); doff = txdcount ? len : 0; } mb_put_uint16le(mbp, txpcount); mb_put_uint16le(mbp, poff); mb_put_uint16le(mbp, totpcount - leftpcount); mb_put_uint16le(mbp, txdcount); mb_put_uint16le(mbp, doff); mb_put_uint16le(mbp, totdcount - leftdcount); leftpcount -= txpcount; leftdcount -= txdcount; if (t2p->t_name == NULL) mb_put_uint16le(mbp, t2p->t2_fid); smb_rq_wend(rqp); smb_rq_bstart(rqp); mb_put_uint8(mbp, 0); /* name */ len = mb_fixhdr(mbp); if (txpcount) { mb_put_mem(mbp, NULL, ALIGN4(len) - len, MB_MZERO); error = md_get_mbuf(&mbparam, txpcount, &m); if (error) goto bad; mb_put_mbuf(mbp, m); } len = mb_fixhdr(mbp); if (txdcount) { mb_put_mem(mbp, NULL, ALIGN4(len) - len, MB_MZERO); error = md_get_mbuf(&mbdata, txdcount, &m); if (error) goto bad; mb_put_mbuf(mbp, m); } smb_rq_bend(rqp); rqp->sr_state = SMBRQ_NOTSENT; error = smb_iod_request(vcp->vc_iod, SMBIOD_EV_NEWRQ, NULL); if (error) goto bad; } /* while left params or data */ t2p->t2_flags |= SMBT2_ALLSENT; mdp = &t2p->t2_rdata; if (mdp->md_top) { m_fixhdr(mdp->md_top); md_initm(mdp, mdp->md_top); } mdp = &t2p->t2_rparam; if (mdp->md_top) { m_fixhdr(mdp->md_top); md_initm(mdp, mdp->md_top); } bad: smb_iod_removerq(rqp); freerq: smb_rq_done(rqp); if (error) { if (rqp->sr_flags & SMBR_RESTART) t2p->t2_flags |= SMBT2_RESTART; md_done(&t2p->t2_rparam); md_done(&t2p->t2_rdata); } return error; } int smb_t2_request(struct smb_t2rq *t2p) { int error = EINVAL, i; for (i = 0; i < SMB_MAXRCN; i++) { t2p->t2_flags &= ~SMBR_RESTART; error = smb_t2_request_int(t2p); if (error == 0) break; if ((t2p->t2_flags & (SMBT2_RESTART | SMBT2_NORESTART)) != SMBT2_RESTART) break; } return error; }