From cc87c47d9d7ac25554aa81cd8ded56e75f79c198 Mon Sep 17 00:00:00 2001 From: Sachin Prabhu Date: Mon, 16 Jun 2014 15:35:28 +0100 Subject: cifs: Separate rawntlmssp auth from CIFS_SessSetup() Separate rawntlmssp authentication from CIFS_SessSetup(). Also cleanup CIFS_SessSetup() since we no longer do any auth within it. Signed-off-by: Sachin Prabhu Reviewed-by: Shirish Pargaonkar Signed-off-by: Steve French --- fs/cifs/sess.c | 490 +++++++++++++++++++++++++++++++-------------------------- 1 file changed, 263 insertions(+), 227 deletions(-) (limited to 'fs/cifs/sess.c') diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index b413fae993aa..c2e7c07c9d5c 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -1113,241 +1113,225 @@ sess_auth_kerberos(struct sess_data *sess_data) } #endif /* ! CONFIG_CIFS_UPCALL */ -int -CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses, - const struct nls_table *nls_cp) +/* + * The required kvec buffers have to be allocated before calling this + * function. + */ +static int +_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data) { - int rc = 0; - int wct; struct smb_hdr *smb_buf; - char *bcc_ptr; - char *str_area; SESSION_SETUP_ANDX *pSMB; + struct cifs_ses *ses = sess_data->ses; __u32 capabilities; - __u16 count; - int resp_buf_type; - struct kvec iov[3]; - enum securityEnum type; - __u16 action, bytes_remaining; - __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */ - u16 blob_len; - char *ntlmsspblob = NULL; - struct sess_data *sess_data; + char *bcc_ptr; - if (ses == NULL) { - WARN(1, "%s: ses == NULL!", __func__); - return -EINVAL; + pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base; + smb_buf = (struct smb_hdr *)pSMB; + + capabilities = cifs_ssetup_hdr(ses, pSMB); + if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) { + cifs_dbg(VFS, "NTLMSSP requires Unicode support\n"); + return -ENOSYS; } - sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL); - if (!sess_data) - return -ENOMEM; - sess_data->xid = xid; - sess_data->ses = ses; - sess_data->buf0_type = CIFS_NO_BUFFER; - sess_data->nls_cp = (struct nls_table *) nls_cp; + pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC; + capabilities |= CAP_EXTENDED_SECURITY; + pSMB->req.Capabilities |= cpu_to_le32(capabilities); - type = select_sectype(ses->server, ses->sectype); - cifs_dbg(FYI, "sess setup type %d\n", type); - if (type == Unspecified) { - cifs_dbg(VFS, - "Unable to select appropriate authentication method!"); - return -EINVAL; + bcc_ptr = sess_data->iov[2].iov_base; + /* unicode strings must be word aligned */ + if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) { + *bcc_ptr = 0; + bcc_ptr++; } + unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp); - switch (type) { - case LANMAN: - sess_auth_lanman(sess_data); - goto out; - case NTLM: - sess_auth_ntlm(sess_data); - goto out; - case NTLMv2: - sess_auth_ntlmv2(sess_data); - goto out; - case Kerberos: - sess_auth_kerberos(sess_data); - goto out; - default: - cifs_dbg(FYI, "Continuing with CIFS_SessSetup\n"); - } + sess_data->iov[2].iov_len = (long) bcc_ptr - + (long) sess_data->iov[2].iov_base; - if (type == RawNTLMSSP) { - /* if memory allocation is successful, caller of this function - * frees it. - */ - ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL); - if (!ses->ntlmssp) - return -ENOMEM; - ses->ntlmssp->sesskey_per_smbsess = false; + return 0; +} + +static void +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data); + +static void +sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data) +{ + int rc; + struct smb_hdr *smb_buf; + SESSION_SETUP_ANDX *pSMB; + struct cifs_ses *ses = sess_data->ses; + __u16 bytes_remaining; + char *bcc_ptr; + u16 blob_len; + + cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n"); + /* + * if memory allocation is successful, caller of this function + * frees it. + */ + ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL); + if (!ses->ntlmssp) { + rc = -ENOMEM; + goto out; } + ses->ntlmssp->sesskey_per_smbsess = false; -ssetup_ntlmssp_authenticate: - if (phase == NtLmChallenge) - phase = NtLmAuthenticate; /* if ntlmssp, now final phase */ + /* wct = 12 */ + rc = sess_alloc_buffer(sess_data, 12); + if (rc) + goto out; - /* same size: negotiate or auth, NTLMSSP or extended security */ - wct = 12; + pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base; - rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses, - (void **)&smb_buf); + /* Build security blob before we assemble the request */ + build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses); + sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE); + sess_data->iov[1].iov_base = pSMB->req.SecurityBlob; + pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE)); + + rc = _sess_auth_rawntlmssp_assemble_req(sess_data); if (rc) - return rc; + goto out; - pSMB = (SESSION_SETUP_ANDX *)smb_buf; + rc = sess_sendreceive(sess_data); - capabilities = cifs_ssetup_hdr(ses, pSMB); + pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base; + smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base; - /* we will send the SMB in three pieces: - a fixed length beginning part, an optional - SPNEGO blob (which can be zero length), and a - last part which will include the strings - and rest of bcc area. This allows us to avoid - a large buffer 17K allocation */ - iov[0].iov_base = (char *)pSMB; - iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4; - - /* setting this here allows the code at the end of the function - to free the request buffer if there's an error */ - resp_buf_type = CIFS_SMALL_BUFFER; + /* If true, rc here is expected and not an error */ + if (sess_data->buf0_type != CIFS_NO_BUFFER && + smb_buf->Status.CifsError == + cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED)) + rc = 0; - /* 2000 big enough to fit max user, domain, NOS name etc. */ - str_area = kmalloc(2000, GFP_KERNEL); - if (str_area == NULL) { - rc = -ENOMEM; - goto ssetup_exit; + if (rc) + goto out; + + cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n"); + + if (smb_buf->WordCount != 4) { + rc = -EIO; + cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount); + goto out; } - bcc_ptr = str_area; - iov[1].iov_base = NULL; - iov[1].iov_len = 0; + ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */ + cifs_dbg(FYI, "UID = %llu\n", ses->Suid); - if (type == RawNTLMSSP) { - if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) { - cifs_dbg(VFS, "NTLMSSP requires Unicode support\n"); - rc = -ENOSYS; - goto ssetup_exit; - } + bytes_remaining = get_bcc(smb_buf); + bcc_ptr = pByteArea(smb_buf); - cifs_dbg(FYI, "ntlmssp session setup phase %d\n", phase); - pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC; - capabilities |= CAP_EXTENDED_SECURITY; - pSMB->req.Capabilities |= cpu_to_le32(capabilities); - switch(phase) { - case NtLmNegotiate: - build_ntlmssp_negotiate_blob( - pSMB->req.SecurityBlob, ses); - iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE); - iov[1].iov_base = pSMB->req.SecurityBlob; - pSMB->req.SecurityBlobLength = - cpu_to_le16(sizeof(NEGOTIATE_MESSAGE)); - break; - case NtLmAuthenticate: - /* - * 5 is an empirical value, large enough to hold - * authenticate message plus max 10 of av paris, - * domain, user, workstation names, flags, etc. - */ - ntlmsspblob = kzalloc( - 5*sizeof(struct _AUTHENTICATE_MESSAGE), - GFP_KERNEL); - if (!ntlmsspblob) { - rc = -ENOMEM; - goto ssetup_exit; - } + blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength); + if (blob_len > bytes_remaining) { + cifs_dbg(VFS, "bad security blob length %d\n", + blob_len); + rc = -EINVAL; + goto out; + } - rc = build_ntlmssp_auth_blob(ntlmsspblob, - &blob_len, ses, nls_cp); - if (rc) - goto ssetup_exit; - iov[1].iov_len = blob_len; - iov[1].iov_base = ntlmsspblob; - pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len); - /* - * Make sure that we tell the server that we are using - * the uid that it just gave us back on the response - * (challenge) - */ - smb_buf->Uid = ses->Suid; - break; - default: - cifs_dbg(VFS, "invalid phase %d\n", phase); - rc = -ENOSYS; - goto ssetup_exit; - } - /* unicode strings must be word aligned */ - if ((iov[0].iov_len + iov[1].iov_len) % 2) { - *bcc_ptr = 0; - bcc_ptr++; - } - unicode_oslm_strings(&bcc_ptr, nls_cp); - } else { - cifs_dbg(VFS, "secType %d not supported!\n", type); - rc = -ENOSYS; - goto ssetup_exit; + rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses); +out: + sess_free_buffer(sess_data); + + if (!rc) { + sess_data->func = sess_auth_rawntlmssp_authenticate; + return; } - iov[2].iov_base = str_area; - iov[2].iov_len = (long) bcc_ptr - (long) str_area; + /* Else error. Cleanup */ + kfree(ses->auth_key.response); + ses->auth_key.response = NULL; + kfree(ses->ntlmssp); + ses->ntlmssp = NULL; - count = iov[1].iov_len + iov[2].iov_len; - smb_buf->smb_buf_length = - cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count); + sess_data->func = NULL; + sess_data->result = rc; +} - put_bcc(count, smb_buf); +static void +sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data) +{ + int rc; + struct smb_hdr *smb_buf; + SESSION_SETUP_ANDX *pSMB; + struct cifs_ses *ses = sess_data->ses; + __u16 bytes_remaining; + char *bcc_ptr; + char *ntlmsspblob = NULL; + u16 blob_len; - rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type, - CIFS_LOG_ERROR); - /* SMB request buf freed in SendReceive2 */ + cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n"); - pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base; - smb_buf = (struct smb_hdr *)iov[0].iov_base; + /* wct = 12 */ + rc = sess_alloc_buffer(sess_data, 12); + if (rc) + goto out; - if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) && - (smb_buf->Status.CifsError == - cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) { - if (phase != NtLmNegotiate) { - cifs_dbg(VFS, "Unexpected more processing error\n"); - goto ssetup_exit; - } - /* NTLMSSP Negotiate sent now processing challenge (response) */ - phase = NtLmChallenge; /* process ntlmssp challenge */ - rc = 0; /* MORE_PROC rc is not an error here, but expected */ + /* Build security blob before we assemble the request */ + pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base; + smb_buf = (struct smb_hdr *)pSMB; + /* + * 5 is an empirical value, large enough to hold + * authenticate message plus max 10 of av paris, + * domain, user, workstation names, flags, etc. + */ + ntlmsspblob = kzalloc(5*sizeof(struct _AUTHENTICATE_MESSAGE), + GFP_KERNEL); + if (!ntlmsspblob) { + rc = -ENOMEM; + goto out; } + + rc = build_ntlmssp_auth_blob(ntlmsspblob, + &blob_len, ses, sess_data->nls_cp); + if (rc) + goto out_free_ntlmsspblob; + sess_data->iov[1].iov_len = blob_len; + sess_data->iov[1].iov_base = ntlmsspblob; + pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len); + /* + * Make sure that we tell the server that we are using + * the uid that it just gave us back on the response + * (challenge) + */ + smb_buf->Uid = ses->Suid; + + rc = _sess_auth_rawntlmssp_assemble_req(sess_data); if (rc) - goto ssetup_exit; + goto out_free_ntlmsspblob; + rc = sess_sendreceive(sess_data); + if (rc) + goto out_free_ntlmsspblob; + + pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base; + smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base; if (smb_buf->WordCount != 4) { rc = -EIO; cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount); - goto ssetup_exit; + goto out_free_ntlmsspblob; } - action = le16_to_cpu(pSMB->resp.Action); - if (action & GUEST_LOGIN) + + if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN) cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */ - ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */ - cifs_dbg(FYI, "UID = %llu\n", ses->Suid); - /* response can have either 3 or 4 word count - Samba sends 3 */ - /* and lanman response is 3 */ + bytes_remaining = get_bcc(smb_buf); bcc_ptr = pByteArea(smb_buf); - blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength); if (blob_len > bytes_remaining) { cifs_dbg(VFS, "bad security blob length %d\n", - blob_len); + blob_len); rc = -EINVAL; - goto ssetup_exit; - } - if (phase == NtLmChallenge) { - rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses); - if (rc) - goto ssetup_exit; + goto out_free_ntlmsspblob; } bcc_ptr += blob_len; bytes_remaining -= blob_len; + /* BB check if Unicode and decode strings */ if (bytes_remaining == 0) { /* no string area to decode, do nothing */ @@ -1357,61 +1341,113 @@ ssetup_ntlmssp_authenticate: ++bcc_ptr; --bytes_remaining; } - decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp); + decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, + sess_data->nls_cp); } else { - decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp); + decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses, + sess_data->nls_cp); } -ssetup_exit: - kfree(str_area); +out_free_ntlmsspblob: kfree(ntlmsspblob); - ntlmsspblob = NULL; - if (resp_buf_type == CIFS_SMALL_BUFFER) { - cifs_dbg(FYI, "ssetup freeing small buf %p\n", iov[0].iov_base); - cifs_small_buf_release(iov[0].iov_base); - } else if (resp_buf_type == CIFS_LARGE_BUFFER) - cifs_buf_release(iov[0].iov_base); - - /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */ - if ((phase == NtLmChallenge) && (rc == 0)) - goto ssetup_ntlmssp_authenticate; - - if (!rc) { - mutex_lock(&ses->server->srv_mutex); - if (!ses->server->session_estab) { - if (ses->server->sign) { - ses->server->session_key.response = - kmemdup(ses->auth_key.response, - ses->auth_key.len, GFP_KERNEL); - if (!ses->server->session_key.response) { - rc = -ENOMEM; - mutex_unlock(&ses->server->srv_mutex); - goto keycp_exit; - } - ses->server->session_key.len = - ses->auth_key.len; - } - ses->server->sequence_number = 0x2; - ses->server->session_estab = true; - } - mutex_unlock(&ses->server->srv_mutex); +out: + sess_free_buffer(sess_data); - cifs_dbg(FYI, "CIFS session established successfully\n"); - spin_lock(&GlobalMid_Lock); - ses->status = CifsGood; - ses->need_reconnect = false; - spin_unlock(&GlobalMid_Lock); - } + if (!rc) + rc = sess_establish_session(sess_data); -keycp_exit: + /* Cleanup */ kfree(ses->auth_key.response); ses->auth_key.response = NULL; kfree(ses->ntlmssp); + ses->ntlmssp = NULL; - return rc; + sess_data->func = NULL; + sess_data->result = rc; +} -out: +int select_sec(struct cifs_ses *ses, struct sess_data *sess_data) +{ + int type; + + type = select_sectype(ses->server, ses->sectype); + cifs_dbg(FYI, "sess setup type %d\n", type); + if (type == Unspecified) { + cifs_dbg(VFS, + "Unable to select appropriate authentication method!"); + return -EINVAL; + } + + switch (type) { + case LANMAN: + /* LANMAN and plaintext are less secure and off by default. + * So we make this explicitly be turned on in kconfig (in the + * build) and turned on at runtime (changed from the default) + * in proc/fs/cifs or via mount parm. Unfortunately this is + * needed for old Win (e.g. Win95), some obscure NAS and OS/2 */ +#ifdef CONFIG_CIFS_WEAK_PW_HASH + sess_data->func = sess_auth_lanman; + break; +#else + return -EOPNOTSUPP; +#endif + case NTLM: + sess_data->func = sess_auth_ntlm; + break; + case NTLMv2: + sess_data->func = sess_auth_ntlmv2; + break; + case Kerberos: +#ifdef CONFIG_CIFS_UPCALL + sess_data->func = sess_auth_kerberos; + break; +#else + cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n"); + return -ENOSYS; + break; +#endif /* CONFIG_CIFS_UPCALL */ + case RawNTLMSSP: + sess_data->func = sess_auth_rawntlmssp_negotiate; + break; + default: + cifs_dbg(VFS, "secType %d not supported!\n", type); + return -ENOSYS; + } + + return 0; +} + +int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses, + const struct nls_table *nls_cp) +{ + int rc = 0; + struct sess_data *sess_data; + + if (ses == NULL) { + WARN(1, "%s: ses == NULL!", __func__); + return -EINVAL; + } + + sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL); + if (!sess_data) + return -ENOMEM; + + rc = select_sec(ses, sess_data); + if (rc) + goto out; + + sess_data->xid = xid; + sess_data->ses = ses; + sess_data->buf0_type = CIFS_NO_BUFFER; + sess_data->nls_cp = (struct nls_table *) nls_cp; + + while (sess_data->func) + sess_data->func(sess_data); + + /* Store result before we free sess_data */ rc = sess_data->result; + +out: kfree(sess_data); return rc; } -- cgit v1.2.3