diff options
| -rw-r--r-- | fs/cifs/smb2pdu.c | 276 |
1 files changed, 230 insertions, 46 deletions
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index d6a045690266..386b512189b2 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -593,6 +593,216 @@ vneg_out: return -EIO; } +struct SMB2_sess_data { + unsigned int xid; + struct cifs_ses *ses; + struct nls_table *nls_cp; + void (*func)(struct SMB2_sess_data *); + int result; + u64 previous_session; + + /* 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 + */ + int buf0_type; + struct kvec iov[2]; +}; + +static int +SMB2_sess_alloc_buffer(struct SMB2_sess_data *sess_data) +{ + int rc; + struct cifs_ses *ses = sess_data->ses; + struct smb2_sess_setup_req *req; + struct TCP_Server_Info *server = ses->server; + + rc = small_smb2_init(SMB2_SESSION_SETUP, NULL, (void **) &req); + if (rc) + return rc; + + req->hdr.SessionId = 0; /* First session, not a reauthenticate */ + + /* if reconnect, we need to send previous sess id, otherwise it is 0 */ + req->PreviousSessionId = sess_data->previous_session; + + req->Flags = 0; /* MBZ */ + /* to enable echos and oplocks */ + req->hdr.CreditRequest = cpu_to_le16(3); + + /* only one of SMB2 signing flags may be set in SMB2 request */ + if (server->sign) + req->SecurityMode = SMB2_NEGOTIATE_SIGNING_REQUIRED; + else if (global_secflags & CIFSSEC_MAY_SIGN) /* one flag unlike MUST_ */ + req->SecurityMode = SMB2_NEGOTIATE_SIGNING_ENABLED; + else + req->SecurityMode = 0; + + req->Capabilities = 0; + req->Channel = 0; /* MBZ */ + + sess_data->iov[0].iov_base = (char *)req; + /* 4 for rfc1002 length field and 1 for pad */ + sess_data->iov[0].iov_len = get_rfc1002_length(req) + 4 - 1; + /* + * This variable will be used to clear the buffer + * allocated above in case of any error in the calling function. + */ + sess_data->buf0_type = CIFS_SMALL_BUFFER; + + return 0; +} + +static void +SMB2_sess_free_buffer(struct SMB2_sess_data *sess_data) +{ + free_rsp_buf(sess_data->buf0_type, sess_data->iov[0].iov_base); + sess_data->buf0_type = CIFS_NO_BUFFER; +} + +static int +SMB2_sess_sendreceive(struct SMB2_sess_data *sess_data) +{ + int rc; + struct smb2_sess_setup_req *req = sess_data->iov[0].iov_base; + + /* Testing shows that buffer offset must be at location of Buffer[0] */ + req->SecurityBufferOffset = + cpu_to_le16(sizeof(struct smb2_sess_setup_req) - + 1 /* pad */ - 4 /* rfc1001 len */); + req->SecurityBufferLength = cpu_to_le16(sess_data->iov[1].iov_len); + + inc_rfc1001_len(req, sess_data->iov[1].iov_len - 1 /* pad */); + + /* BB add code to build os and lm fields */ + + rc = SendReceive2(sess_data->xid, sess_data->ses, + sess_data->iov, 2, + &sess_data->buf0_type, + CIFS_LOG_ERROR | CIFS_NEG_OP); + + return rc; +} + +static int +SMB2_sess_establish_session(struct SMB2_sess_data *sess_data) +{ + int rc = 0; + struct cifs_ses *ses = sess_data->ses; + + mutex_lock(&ses->server->srv_mutex); + if (ses->server->sign && ses->server->ops->generate_signingkey) { + rc = ses->server->ops->generate_signingkey(ses); + kfree(ses->auth_key.response); + ses->auth_key.response = NULL; + if (rc) { + cifs_dbg(FYI, + "SMB3 session key generation failed\n"); + mutex_unlock(&ses->server->srv_mutex); + goto keygen_exit; + } + } + if (!ses->server->session_estab) { + ses->server->sequence_number = 0x2; + ses->server->session_estab = true; + } + mutex_unlock(&ses->server->srv_mutex); + + cifs_dbg(FYI, "SMB2/3 session established successfully\n"); + spin_lock(&GlobalMid_Lock); + ses->status = CifsGood; + ses->need_reconnect = false; + spin_unlock(&GlobalMid_Lock); + +keygen_exit: + if (!ses->server->sign) { + kfree(ses->auth_key.response); + ses->auth_key.response = NULL; + } + return rc; +} + +#ifdef CONFIG_CIFS_UPCALL +static void +SMB2_auth_kerberos(struct SMB2_sess_data *sess_data) +{ + int rc; + struct cifs_ses *ses = sess_data->ses; + struct cifs_spnego_msg *msg; + struct key *spnego_key = NULL; + struct smb2_sess_setup_rsp *rsp = NULL; + + rc = SMB2_sess_alloc_buffer(sess_data); + if (rc) + goto out; + + spnego_key = cifs_get_spnego_key(ses); + if (IS_ERR(spnego_key)) { + rc = PTR_ERR(spnego_key); + spnego_key = NULL; + goto out; + } + + msg = spnego_key->payload.data[0]; + /* + * check version field to make sure that cifs.upcall is + * sending us a response in an expected form + */ + if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) { + cifs_dbg(VFS, + "bad cifs.upcall version. Expected %d got %d", + CIFS_SPNEGO_UPCALL_VERSION, msg->version); + rc = -EKEYREJECTED; + goto out_put_spnego_key; + } + + ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len, + GFP_KERNEL); + if (!ses->auth_key.response) { + cifs_dbg(VFS, + "Kerberos can't allocate (%u bytes) memory", + msg->sesskey_len); + rc = -ENOMEM; + goto out_put_spnego_key; + } + ses->auth_key.len = msg->sesskey_len; + + sess_data->iov[1].iov_base = msg->data + msg->sesskey_len; + sess_data->iov[1].iov_len = msg->secblob_len; + + rc = SMB2_sess_sendreceive(sess_data); + if (rc) + goto out_put_spnego_key; + + rsp = (struct smb2_sess_setup_rsp *)sess_data->iov[0].iov_base; + ses->Suid = rsp->hdr.SessionId; + + ses->session_flags = le16_to_cpu(rsp->SessionFlags); + if (ses->session_flags & SMB2_SESSION_FLAG_ENCRYPT_DATA) + cifs_dbg(VFS, "SMB3 encryption not supported yet\n"); + + rc = SMB2_sess_establish_session(sess_data); +out_put_spnego_key: + key_invalidate(spnego_key); + key_put(spnego_key); +out: + sess_data->result = rc; + sess_data->func = NULL; + SMB2_sess_free_buffer(sess_data); +} +#else +static void +SMB2_auth_kerberos(struct SMB2_sess_data *sess_data) +{ + cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n"); + sess_data->result = -EOPNOTSUPP; + sess_data->func = NULL; +} +#endif + int SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *nls_cp) @@ -605,11 +815,11 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */ struct TCP_Server_Info *server = ses->server; u16 blob_length = 0; - struct key *spnego_key = NULL; char *security_blob = NULL; unsigned char *ntlmssp_blob = NULL; bool use_spnego = false; /* else use raw ntlmssp */ u64 previous_session = ses->Suid; + struct SMB2_sess_data *sess_data; cifs_dbg(FYI, "Session Setup\n"); @@ -618,6 +828,20 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses, return -EIO; } + sess_data = kzalloc(sizeof(struct SMB2_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; + sess_data->previous_session = ses->Suid; + + if (ses->sectype == Kerberos) { + SMB2_auth_kerberos(sess_data); + goto out; + } + /* * If we are here due to reconnect, free per-smb session key * in case signing was required. @@ -670,47 +894,7 @@ ssetup_ntlmssp_authenticate: /* 4 for rfc1002 length field and 1 for pad */ iov[0].iov_len = get_rfc1002_length(req) + 4 - 1; - if (ses->sectype == Kerberos) { -#ifdef CONFIG_CIFS_UPCALL - struct cifs_spnego_msg *msg; - - spnego_key = cifs_get_spnego_key(ses); - if (IS_ERR(spnego_key)) { - rc = PTR_ERR(spnego_key); - spnego_key = NULL; - goto ssetup_exit; - } - - msg = spnego_key->payload.data[0]; - /* - * check version field to make sure that cifs.upcall is - * sending us a response in an expected form - */ - if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) { - cifs_dbg(VFS, - "bad cifs.upcall version. Expected %d got %d", - CIFS_SPNEGO_UPCALL_VERSION, msg->version); - rc = -EKEYREJECTED; - goto ssetup_exit; - } - ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len, - GFP_KERNEL); - if (!ses->auth_key.response) { - cifs_dbg(VFS, - "Kerberos can't allocate (%u bytes) memory", - msg->sesskey_len); - rc = -ENOMEM; - goto ssetup_exit; - } - ses->auth_key.len = msg->sesskey_len; - blob_length = msg->secblob_len; - iov[1].iov_base = msg->data + msg->sesskey_len; - iov[1].iov_len = blob_length; -#else - rc = -EOPNOTSUPP; - goto ssetup_exit; -#endif /* CONFIG_CIFS_UPCALL */ - } else if (phase == NtLmNegotiate) { /* if not krb5 must be ntlmssp */ + if (phase == NtLmNegotiate) { ntlmssp_blob = kmalloc(sizeof(struct _NEGOTIATE_MESSAGE), GFP_KERNEL); if (ntlmssp_blob == NULL) { @@ -853,13 +1037,13 @@ keygen_exit: kfree(ses->auth_key.response); ses->auth_key.response = NULL; } - if (spnego_key) { - key_invalidate(spnego_key); - key_put(spnego_key); - } kfree(ses->ntlmssp); return rc; +out: + rc = sess_data->result; + kfree(sess_data); + return rc; } int |