From 396d7a7dd3d1583109b477ea5b223670903cde0d Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Sat, 3 Sep 2011 10:18:32 +0200 Subject: smbXcli: add support for smb2 signing metze --- libcli/smb/smbXcli_base.c | 149 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 144 insertions(+), 5 deletions(-) (limited to 'libcli') diff --git a/libcli/smb/smbXcli_base.c b/libcli/smb/smbXcli_base.c index 2cb5d449d94..e2ff0174651 100644 --- a/libcli/smb/smbXcli_base.c +++ b/libcli/smb/smbXcli_base.c @@ -139,6 +139,7 @@ struct smbXcli_session { struct smbXcli_req_state { struct tevent_context *ev; struct smbXcli_conn *conn; + struct smbXcli_session *session; /* maybe NULL */ uint8_t length_hdr[4]; @@ -188,6 +189,8 @@ struct smbXcli_req_state { struct iovec *recv_iov; uint16_t credit_charge; + + bool signing_skipped; } smb2; }; @@ -2101,6 +2104,7 @@ NTSTATUS smb2cli_req_compound_submit(struct tevent_req **reqs, nbt_len = 0; for (i=0; ismb2.hdr, SMB2_HDR_CREDIT, credits); SBVAL(state->smb2.hdr, SMB2_HDR_MESSAGE_ID, mid); + hdr_iov = num_iov; iov[num_iov].iov_base = state->smb2.hdr; iov[num_iov].iov_len = sizeof(state->smb2.hdr); num_iov += 1; @@ -2190,16 +2195,22 @@ NTSTATUS smb2cli_req_compound_submit(struct tevent_req **reqs, } nbt_len += reqlen; + if (state->session && state->session->smb2.should_sign) { + NTSTATUS status; + + status = smb2_signing_sign_pdu(state->session->smb2.signing_key, + &iov[hdr_iov], num_iov - hdr_iov); + if (!NT_STATUS_IS_OK(status)) { + return status; + } + } + ret = smbXcli_req_set_pending(reqs[i]); if (!ret) { return NT_STATUS_NO_MEMORY; } } - /* - * TODO: Do signing here - */ - state = tevent_req_data(reqs[0], struct smbXcli_req_state); _smb_setlen_tcp(state->length_hdr, nbt_len); iov[0].iov_base = state->length_hdr; @@ -2413,6 +2424,7 @@ static NTSTATUS smb2cli_conn_dispatch_incoming(struct smbXcli_conn *conn, int i, num_iov; NTSTATUS status; bool defer = true; + struct smbXcli_session *last_session = NULL; status = smb2cli_inbuf_parse_compound(inbuf, tmp_mem, &iov, &num_iov); @@ -2428,8 +2440,11 @@ static NTSTATUS smb2cli_conn_dispatch_incoming(struct smbXcli_conn *conn, uint32_t flags = IVAL(inhdr, SMB2_HDR_FLAGS); uint64_t mid = BVAL(inhdr, SMB2_HDR_MESSAGE_ID); uint16_t req_opcode; + uint32_t req_flags; uint16_t credits = SVAL(inhdr, SMB2_HDR_CREDIT); uint32_t new_credits; + struct smbXcli_session *session = NULL; + const DATA_BLOB *signing_key = NULL; new_credits = conn->smb2.cur_credits; new_credits += credits; @@ -2448,6 +2463,7 @@ static NTSTATUS smb2cli_conn_dispatch_incoming(struct smbXcli_conn *conn, if (opcode != req_opcode) { return NT_STATUS_INVALID_NETWORK_RESPONSE; } + req_flags = SVAL(state->smb2.hdr, SMB2_HDR_FLAGS); if (!(flags & SMB2_HDR_FLAG_REDIRECT)) { return NT_STATUS_INVALID_NETWORK_RESPONSE; @@ -2456,15 +2472,129 @@ static NTSTATUS smb2cli_conn_dispatch_incoming(struct smbXcli_conn *conn, status = NT_STATUS(IVAL(inhdr, SMB2_HDR_STATUS)); if ((flags & SMB2_HDR_FLAG_ASYNC) && NT_STATUS_EQUAL(status, STATUS_PENDING)) { - uint32_t req_flags = IVAL(state->smb2.hdr, SMB2_HDR_FLAGS); uint64_t async_id = BVAL(inhdr, SMB2_HDR_ASYNC_ID); + /* + * async interim responses are not signed, + * even if the SMB2_HDR_FLAG_SIGNED flag + * is set. + */ req_flags |= SMB2_HDR_FLAG_ASYNC; SBVAL(state->smb2.hdr, SMB2_HDR_FLAGS, req_flags); SBVAL(state->smb2.hdr, SMB2_HDR_ASYNC_ID, async_id); continue; } + session = state->session; + if (req_flags & SMB2_HDR_FLAG_CHAINED) { + session = last_session; + } + last_session = session; + + if (session && session->smb2.should_sign) { + if (!(flags & SMB2_HDR_FLAG_SIGNED)) { + return NT_STATUS_ACCESS_DENIED; + } + } + + if (flags & SMB2_HDR_FLAG_SIGNED) { + uint64_t uid = BVAL(inhdr, SMB2_HDR_SESSION_ID); + + if (session == NULL) { + struct smbXcli_session *s; + + s = state->conn->sessions; + for (; s; s = s->next) { + if (s->smb2.session_id != uid) { + continue; + } + + session = s; + break; + } + } + + if (session == NULL) { + return NT_STATUS_INVALID_NETWORK_RESPONSE; + } + + last_session = session; + signing_key = &session->smb2.signing_key; + } + + if ((opcode == SMB2_OP_SESSSETUP) && + NT_STATUS_IS_OK(status)) { + /* + * the caller has to check the signing + * as only the caller knows the correct + * session key + */ + signing_key = NULL; + } + + if (NT_STATUS_EQUAL(status, NT_STATUS_USER_SESSION_DELETED)) { + /* + * if the server returns NT_STATUS_USER_SESSION_DELETED + * the response is not signed and we should + * propagate the NT_STATUS_USER_SESSION_DELETED + * status to the caller. + */ + if (signing_key) { + signing_key = NULL; + } + } + + if (NT_STATUS_EQUAL(status, NT_STATUS_NETWORK_NAME_DELETED) || + NT_STATUS_EQUAL(status, NT_STATUS_FILE_CLOSED) || + NT_STATUS_EQUAL(status, NT_STATUS_INVALID_PARAMETER)) { + /* + * if the server returns + * NT_STATUS_NETWORK_NAME_DELETED + * NT_STATUS_FILE_CLOSED + * NT_STATUS_INVALID_PARAMETER + * the response might not be signed + * as this happens before the signing checks. + * + * If server echos the signature (or all zeros) + * we should report the status from the server + * to the caller. + */ + if (signing_key) { + int cmp; + + cmp = memcmp(inhdr+SMB2_HDR_SIGNATURE, + state->smb2.hdr+SMB2_HDR_SIGNATURE, + 16); + if (cmp == 0) { + state->smb2.signing_skipped = true; + signing_key = NULL; + } + } + if (signing_key) { + int cmp; + static const uint8_t zeros[16]; + + cmp = memcmp(inhdr+SMB2_HDR_SIGNATURE, + zeros, + 16); + if (cmp == 0) { + state->smb2.signing_skipped = true; + signing_key = NULL; + } + } + } + + if (signing_key) { + status = smb2_signing_check_pdu(*signing_key, cur, 3); + if (!NT_STATUS_IS_OK(status)) { + /* + * If the signing check fails, we disconnect + * the connection. + */ + return status; + } + } + smbXcli_req_unset_pending(req); /* @@ -2565,6 +2695,15 @@ NTSTATUS smb2cli_req_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, return status; } + if (state->smb2.signing_skipped) { + if (num_expected > 0) { + return NT_STATUS_ACCESS_DENIED; + } + if (!NT_STATUS_IS_ERR(status)) { + return NT_STATUS_ACCESS_DENIED; + } + } + if (!found_size) { return NT_STATUS_INVALID_NETWORK_RESPONSE; } -- cgit v1.2.1