/* Unix SMB/CIFS implementation. dcerpc schannel operations Copyright (C) Andrew Tridgell 2004 Copyright (C) Andrew Bartlett 2004-2005 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include "includes.h" #include #include "lib/util/tevent_ntstatus.h" #include "librpc/gen_ndr/ndr_schannel.h" #include "auth/auth.h" #include "auth/credentials/credentials.h" #include "auth/gensec/gensec.h" #include "auth/gensec/gensec_internal.h" #include "auth/gensec/gensec_proto.h" #include "../libcli/auth/schannel.h" #include "librpc/gen_ndr/dcerpc.h" #include "param/param.h" #include "auth/gensec/gensec_toplevel_proto.h" #include "libds/common/roles.h" #ifndef HAVE_GNUTLS_AES_CFB8 #include "lib/crypto/aes.h" #endif #include "lib/crypto/gnutls_helpers.h" #include #include #undef DBGC_CLASS #define DBGC_CLASS DBGC_AUTH struct schannel_state { struct gensec_security *gensec; uint64_t seq_num; bool initiator; struct netlogon_creds_CredentialState *creds; struct auth_user_info_dc *user_info_dc; }; #define SETUP_SEQNUM(state, buf, initiator) do { \ uint8_t *_buf = buf; \ uint32_t _seq_num_low = (state)->seq_num & UINT32_MAX; \ uint32_t _seq_num_high = (state)->seq_num >> 32; \ if (initiator) { \ _seq_num_high |= 0x80000000; \ } \ RSIVAL(_buf, 0, _seq_num_low); \ RSIVAL(_buf, 4, _seq_num_high); \ } while(0) static struct schannel_state *netsec_create_state( struct gensec_security *gensec, struct netlogon_creds_CredentialState *creds, bool initiator) { struct schannel_state *state; state = talloc_zero(gensec, struct schannel_state); if (state == NULL) { return NULL; } state->gensec = gensec; state->initiator = initiator; state->creds = netlogon_creds_copy(state, creds); if (state->creds == NULL) { talloc_free(state); return NULL; } gensec->private_data = state; return state; } static void netsec_offset_and_sizes(struct schannel_state *state, bool do_seal, uint32_t *_min_sig_size, uint32_t *_used_sig_size, uint32_t *_checksum_length, uint32_t *_confounder_ofs) { uint32_t min_sig_size; uint32_t used_sig_size; uint32_t checksum_length; uint32_t confounder_ofs; if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) { min_sig_size = 48; used_sig_size = 56; /* * Note: windows has a bug here and uses the old values... * * checksum_length = 32; * confounder_ofs = 48; */ checksum_length = 8; confounder_ofs = 24; } else { min_sig_size = 24; used_sig_size = 32; checksum_length = 8; confounder_ofs = 24; } if (do_seal) { min_sig_size += 8; } if (_min_sig_size) { *_min_sig_size = min_sig_size; } if (_used_sig_size) { *_used_sig_size = used_sig_size; } if (_checksum_length) { *_checksum_length = checksum_length; } if (_confounder_ofs) { *_confounder_ofs = confounder_ofs; } } /******************************************************************* Encode or Decode the sequence number (which is symmetric) ********************************************************************/ static NTSTATUS netsec_do_seq_num(struct schannel_state *state, const uint8_t *checksum, uint32_t checksum_length, uint8_t seq_num[8]) { if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) { #ifdef HAVE_GNUTLS_AES_CFB8 gnutls_cipher_hd_t cipher_hnd = NULL; gnutls_datum_t key = { .data = state->creds->session_key, .size = sizeof(state->creds->session_key), }; uint32_t iv_size = gnutls_cipher_get_iv_size(GNUTLS_CIPHER_AES_128_CFB8); uint8_t _iv[iv_size]; gnutls_datum_t iv = { .data = _iv, .size = iv_size, }; int rc; ZERO_ARRAY(_iv); memcpy(iv.data + 0, checksum, 8); memcpy(iv.data + 8, checksum, 8); rc = gnutls_cipher_init(&cipher_hnd, GNUTLS_CIPHER_AES_128_CFB8, &key, &iv); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } rc = gnutls_cipher_encrypt(cipher_hnd, seq_num, 8); gnutls_cipher_deinit(cipher_hnd); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } #else /* NOT HAVE_GNUTLS_AES_CFB8 */ AES_KEY key; uint8_t iv[AES_BLOCK_SIZE]; AES_set_encrypt_key(state->creds->session_key, 128, &key); ZERO_STRUCT(iv); memcpy(iv+0, checksum, 8); memcpy(iv+8, checksum, 8); aes_cfb8_encrypt(seq_num, seq_num, 8, &key, iv, AES_ENCRYPT); #endif /* HAVE_GNUTLS_AES_CFB8 */ } else { static const uint8_t zeros[4]; uint8_t _sequence_key[16]; gnutls_cipher_hd_t cipher_hnd; gnutls_datum_t sequence_key = { .data = _sequence_key, .size = sizeof(_sequence_key), }; uint8_t digest1[16]; int rc; rc = gnutls_hmac_fast(GNUTLS_MAC_MD5, state->creds->session_key, sizeof(state->creds->session_key), zeros, sizeof(zeros), digest1); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_hmac_fast(GNUTLS_MAC_MD5, digest1, sizeof(digest1), checksum, checksum_length, _sequence_key); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } ZERO_ARRAY(digest1); rc = gnutls_cipher_init(&cipher_hnd, GNUTLS_CIPHER_ARCFOUR_128, &sequence_key, NULL); if (rc < 0) { ZERO_ARRAY(_sequence_key); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_cipher_encrypt(cipher_hnd, seq_num, 8); gnutls_cipher_deinit(cipher_hnd); ZERO_ARRAY(_sequence_key); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } state->seq_num++; return NT_STATUS_OK; } static NTSTATUS netsec_do_seal(struct schannel_state *state, const uint8_t seq_num[8], uint8_t confounder[8], uint8_t *data, uint32_t length, bool forward) { if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) { #ifdef HAVE_GNUTLS_AES_CFB8 gnutls_cipher_hd_t cipher_hnd = NULL; uint8_t sess_kf0[16] = {0}; gnutls_datum_t key = { .data = sess_kf0, .size = sizeof(sess_kf0), }; uint32_t iv_size = gnutls_cipher_get_iv_size(GNUTLS_CIPHER_AES_128_CFB8); uint8_t _iv[iv_size]; gnutls_datum_t iv = { .data = _iv, .size = iv_size, }; uint32_t i; int rc; for (i = 0; i < key.size; i++) { key.data[i] = state->creds->session_key[i] ^ 0xf0; } ZERO_ARRAY(_iv); memcpy(iv.data + 0, seq_num, 8); memcpy(iv.data + 8, seq_num, 8); rc = gnutls_cipher_init(&cipher_hnd, GNUTLS_CIPHER_AES_128_CFB8, &key, &iv); if (rc < 0) { DBG_ERR("ERROR: gnutls_cipher_init: %s\n", gnutls_strerror(rc)); return NT_STATUS_NO_MEMORY; } if (forward) { rc = gnutls_cipher_encrypt(cipher_hnd, confounder, 8); if (rc < 0) { gnutls_cipher_deinit(cipher_hnd); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } rc = gnutls_cipher_encrypt(cipher_hnd, data, length); if (rc < 0) { gnutls_cipher_deinit(cipher_hnd); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } } else { /* * Workaround bug present in gnutls 3.6.8: * * gnutls_cipher_decrypt() uses an optimization * internally that breaks decryption when processing * buffers with their length not being a multiple * of the blocksize. */ uint8_t tmp[16] = { 0, }; uint32_t tmp_dlength = MIN(length, sizeof(tmp) - 8); memcpy(tmp, confounder, 8); memcpy(tmp + 8, data, tmp_dlength); rc = gnutls_cipher_decrypt(cipher_hnd, tmp, 8 + tmp_dlength); if (rc < 0) { ZERO_STRUCT(tmp); gnutls_cipher_deinit(cipher_hnd); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } memcpy(confounder, tmp, 8); memcpy(data, tmp + 8, tmp_dlength); ZERO_STRUCT(tmp); if (length > tmp_dlength) { rc = gnutls_cipher_decrypt(cipher_hnd, data + tmp_dlength, length - tmp_dlength); if (rc < 0) { gnutls_cipher_deinit(cipher_hnd); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } } } gnutls_cipher_deinit(cipher_hnd); #else /* NOT HAVE_GNUTLS_AES_CFB8 */ AES_KEY key; uint8_t iv[AES_BLOCK_SIZE]; uint8_t sess_kf0[16]; int i; for (i = 0; i < 16; i++) { sess_kf0[i] = state->creds->session_key[i] ^ 0xf0; } AES_set_encrypt_key(sess_kf0, 128, &key); ZERO_STRUCT(iv); memcpy(iv+0, seq_num, 8); memcpy(iv+8, seq_num, 8); if (forward) { aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_ENCRYPT); aes_cfb8_encrypt(data, data, length, &key, iv, AES_ENCRYPT); } else { aes_cfb8_encrypt(confounder, confounder, 8, &key, iv, AES_DECRYPT); aes_cfb8_encrypt(data, data, length, &key, iv, AES_DECRYPT); } #endif /* HAVE_GNUTLS_AES_CFB8 */ } else { gnutls_cipher_hd_t cipher_hnd; uint8_t _sealing_key[16]; gnutls_datum_t sealing_key = { .data = _sealing_key, .size = sizeof(_sealing_key), }; static const uint8_t zeros[4]; uint8_t digest2[16]; uint8_t sess_kf0[16]; int rc; int i; for (i = 0; i < 16; i++) { sess_kf0[i] = state->creds->session_key[i] ^ 0xf0; } rc = gnutls_hmac_fast(GNUTLS_MAC_MD5, sess_kf0, sizeof(sess_kf0), zeros, 4, digest2); if (rc < 0) { ZERO_ARRAY(digest2); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_hmac_fast(GNUTLS_MAC_MD5, digest2, sizeof(digest2), seq_num, 8, _sealing_key); ZERO_ARRAY(digest2); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_cipher_init(&cipher_hnd, GNUTLS_CIPHER_ARCFOUR_128, &sealing_key, NULL); if (rc < 0) { ZERO_ARRAY(_sealing_key); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } rc = gnutls_cipher_encrypt(cipher_hnd, confounder, 8); if (rc < 0) { ZERO_ARRAY(_sealing_key); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } gnutls_cipher_deinit(cipher_hnd); rc = gnutls_cipher_init(&cipher_hnd, GNUTLS_CIPHER_ARCFOUR_128, &sealing_key, NULL); if (rc < 0) { ZERO_ARRAY(_sealing_key); return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } rc = gnutls_cipher_encrypt(cipher_hnd, data, length); gnutls_cipher_deinit(cipher_hnd); ZERO_ARRAY(_sealing_key); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_CRYPTO_SYSTEM_INVALID); } } return NT_STATUS_OK; } /******************************************************************* Create a digest over the entire packet (including the data), and MD5 it with the session key. ********************************************************************/ static NTSTATUS netsec_do_sign(struct schannel_state *state, const uint8_t *confounder, const uint8_t *data, size_t length, uint8_t header[8], uint8_t *checksum) { if (state->creds->negotiate_flags & NETLOGON_NEG_SUPPORTS_AES) { gnutls_hmac_hd_t hmac_hnd = NULL; int rc; rc = gnutls_hmac_init(&hmac_hnd, GNUTLS_MAC_SHA256, state->creds->session_key, sizeof(state->creds->session_key)); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } if (confounder) { SSVAL(header, 0, NL_SIGN_HMAC_SHA256); SSVAL(header, 2, NL_SEAL_AES128); SSVAL(header, 4, 0xFFFF); SSVAL(header, 6, 0x0000); rc = gnutls_hmac(hmac_hnd, header, 8); if (rc < 0) { gnutls_hmac_deinit(hmac_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_hmac(hmac_hnd, confounder, 8); if (rc < 0) { gnutls_hmac_deinit(hmac_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } else { SSVAL(header, 0, NL_SIGN_HMAC_SHA256); SSVAL(header, 2, NL_SEAL_NONE); SSVAL(header, 4, 0xFFFF); SSVAL(header, 6, 0x0000); rc = gnutls_hmac(hmac_hnd, header, 8); if (rc < 0) { gnutls_hmac_deinit(hmac_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } rc = gnutls_hmac(hmac_hnd, data, length); if (rc < 0) { gnutls_hmac_deinit(hmac_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } gnutls_hmac_deinit(hmac_hnd, checksum); } else { uint8_t packet_digest[16]; static const uint8_t zeros[4]; gnutls_hash_hd_t hash_hnd = NULL; int rc; rc = gnutls_hash_init(&hash_hnd, GNUTLS_DIG_MD5); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_hash(hash_hnd, zeros, sizeof(zeros)); if (rc < 0) { gnutls_hash_deinit(hash_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } if (confounder) { SSVAL(header, 0, NL_SIGN_HMAC_MD5); SSVAL(header, 2, NL_SEAL_RC4); SSVAL(header, 4, 0xFFFF); SSVAL(header, 6, 0x0000); rc = gnutls_hash(hash_hnd, header, 8); if (rc < 0) { gnutls_hash_deinit(hash_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } rc = gnutls_hash(hash_hnd, confounder, 8); if (rc < 0) { gnutls_hash_deinit(hash_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } else { SSVAL(header, 0, NL_SIGN_HMAC_MD5); SSVAL(header, 2, NL_SEAL_NONE); SSVAL(header, 4, 0xFFFF); SSVAL(header, 6, 0x0000); rc = gnutls_hash(hash_hnd, header, 8); if (rc < 0) { gnutls_hash_deinit(hash_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } rc = gnutls_hash(hash_hnd, data, length); if (rc < 0) { gnutls_hash_deinit(hash_hnd, NULL); return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } gnutls_hash_deinit(hash_hnd, packet_digest); rc = gnutls_hmac_fast(GNUTLS_MAC_MD5, state->creds->session_key, sizeof(state->creds->session_key), packet_digest, sizeof(packet_digest), checksum); ZERO_ARRAY(packet_digest); if (rc < 0) { return gnutls_error_to_ntstatus(rc, NT_STATUS_HMAC_NOT_SUPPORTED); } } return NT_STATUS_OK; } static NTSTATUS netsec_incoming_packet(struct schannel_state *state, bool do_unseal, uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, const DATA_BLOB *sig) { uint32_t min_sig_size = 0; uint8_t header[8]; uint8_t checksum[32]; uint32_t checksum_length = sizeof(checksum_length); uint8_t _confounder[8]; uint8_t *confounder = NULL; uint32_t confounder_ofs = 0; uint8_t seq_num[8]; bool ret; const uint8_t *sign_data = NULL; size_t sign_length = 0; NTSTATUS status; netsec_offset_and_sizes(state, do_unseal, &min_sig_size, NULL, &checksum_length, &confounder_ofs); if (sig->length < min_sig_size) { return NT_STATUS_ACCESS_DENIED; } if (do_unseal) { confounder = _confounder; memcpy(confounder, sig->data+confounder_ofs, 8); } else { confounder = NULL; } SETUP_SEQNUM(state, seq_num, !state->initiator); if (do_unseal) { status = netsec_do_seal(state, seq_num, confounder, data, length, false); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_seal failed: %s\n", nt_errstr(status)); return NT_STATUS_ACCESS_DENIED; } } if (state->gensec->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) { sign_data = whole_pdu; sign_length = pdu_length; } else { sign_data = data; sign_length = length; } status = netsec_do_sign(state, confounder, sign_data, sign_length, header, checksum); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_sign failed: %s\n", nt_errstr(status)); return NT_STATUS_ACCESS_DENIED; } ret = mem_equal_const_time(checksum, sig->data+16, checksum_length); if (!ret) { dump_data_pw("calc digest:", checksum, checksum_length); dump_data_pw("wire digest:", sig->data+16, checksum_length); return NT_STATUS_ACCESS_DENIED; } status = netsec_do_seq_num(state, checksum, checksum_length, seq_num); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_seq_num failed: %s\n", nt_errstr(status)); return status; } ZERO_ARRAY(checksum); ret = mem_equal_const_time(seq_num, sig->data+8, 8); if (!ret) { dump_data_pw("calc seq num:", seq_num, 8); dump_data_pw("wire seq num:", sig->data+8, 8); return NT_STATUS_ACCESS_DENIED; } return NT_STATUS_OK; } static uint32_t netsec_outgoing_sig_size(struct schannel_state *state) { uint32_t sig_size = 0; netsec_offset_and_sizes(state, true, NULL, &sig_size, NULL, NULL); return sig_size; } static NTSTATUS netsec_outgoing_packet(struct schannel_state *state, TALLOC_CTX *mem_ctx, bool do_seal, uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, DATA_BLOB *sig) { uint32_t min_sig_size = 0; uint32_t used_sig_size = 0; uint8_t header[8]; uint8_t checksum[32]; uint32_t checksum_length = sizeof(checksum_length); uint8_t _confounder[8]; uint8_t *confounder = NULL; uint32_t confounder_ofs = 0; uint8_t seq_num[8]; const uint8_t *sign_data = NULL; size_t sign_length = 0; NTSTATUS status; netsec_offset_and_sizes(state, do_seal, &min_sig_size, &used_sig_size, &checksum_length, &confounder_ofs); SETUP_SEQNUM(state, seq_num, state->initiator); if (do_seal) { confounder = _confounder; generate_random_buffer(confounder, 8); } else { confounder = NULL; } if (state->gensec->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) { sign_data = whole_pdu; sign_length = pdu_length; } else { sign_data = data; sign_length = length; } status = netsec_do_sign(state, confounder, sign_data, sign_length, header, checksum); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_sign failed: %s\n", nt_errstr(status)); return NT_STATUS_ACCESS_DENIED; } if (do_seal) { status = netsec_do_seal(state, seq_num, confounder, data, length, true); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_seal failed: %s\n", nt_errstr(status)); return status; } } status = netsec_do_seq_num(state, checksum, checksum_length, seq_num); if (!NT_STATUS_IS_OK(status)) { DBG_WARNING("netsec_do_seq_num failed: %s\n", nt_errstr(status)); return status; } (*sig) = data_blob_talloc_zero(mem_ctx, used_sig_size); memcpy(sig->data, header, 8); memcpy(sig->data+8, seq_num, 8); memcpy(sig->data+16, checksum, checksum_length); if (confounder) { memcpy(sig->data+confounder_ofs, confounder, 8); } dump_data_pw("signature:", sig->data+ 0, 8); dump_data_pw("seq_num :", sig->data+ 8, 8); dump_data_pw("digest :", sig->data+16, checksum_length); dump_data_pw("confound :", sig->data+confounder_ofs, 8); return NT_STATUS_OK; } _PUBLIC_ NTSTATUS gensec_schannel_init(TALLOC_CTX *ctx); static size_t schannel_sig_size(struct gensec_security *gensec_security, size_t data_size) { struct schannel_state *state = talloc_get_type_abort(gensec_security->private_data, struct schannel_state); return netsec_outgoing_sig_size(state); } struct schannel_update_state { NTSTATUS status; DATA_BLOB out; }; static NTSTATUS schannel_update_internal(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, const DATA_BLOB in, DATA_BLOB *out); static struct tevent_req *schannel_update_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev, struct gensec_security *gensec_security, const DATA_BLOB in) { struct tevent_req *req; struct schannel_update_state *state = NULL; NTSTATUS status; req = tevent_req_create(mem_ctx, &state, struct schannel_update_state); if (req == NULL) { return NULL; } status = schannel_update_internal(gensec_security, state, in, &state->out); state->status = status; if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) { status = NT_STATUS_OK; } if (tevent_req_nterror(req, status)) { return tevent_req_post(req, ev); } tevent_req_done(req); return tevent_req_post(req, ev); } static NTSTATUS schannel_update_internal(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, const DATA_BLOB in, DATA_BLOB *out) { struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state); NTSTATUS status; enum ndr_err_code ndr_err; struct NL_AUTH_MESSAGE bind_schannel = { .Flags = 0, }; struct NL_AUTH_MESSAGE bind_schannel_ack; struct netlogon_creds_CredentialState *creds; const char *workstation; const char *domain; *out = data_blob(NULL, 0); if (gensec_security->dcerpc_auth_level < DCERPC_AUTH_LEVEL_INTEGRITY) { switch (gensec_security->gensec_role) { case GENSEC_CLIENT: return NT_STATUS_INVALID_PARAMETER_MIX; case GENSEC_SERVER: return NT_STATUS_INVALID_PARAMETER; } return NT_STATUS_INTERNAL_ERROR; } switch (gensec_security->gensec_role) { case GENSEC_CLIENT: if (state != NULL) { /* we could parse the bind ack, but we don't know what it is yet */ return NT_STATUS_OK; } creds = cli_credentials_get_netlogon_creds(gensec_security->credentials); if (creds == NULL) { return NT_STATUS_INVALID_PARAMETER_MIX; } state = netsec_create_state(gensec_security, creds, true /* initiator */); if (state == NULL) { return NT_STATUS_NO_MEMORY; } bind_schannel.MessageType = NL_NEGOTIATE_REQUEST; bind_schannel.Flags = NL_FLAG_OEM_NETBIOS_DOMAIN_NAME | NL_FLAG_OEM_NETBIOS_COMPUTER_NAME; bind_schannel.oem_netbios_domain.a = cli_credentials_get_domain(gensec_security->credentials); bind_schannel.oem_netbios_computer.a = creds->computer_name; if (creds->secure_channel_type == SEC_CHAN_DNS_DOMAIN) { bind_schannel.Flags |= NL_FLAG_UTF8_DNS_DOMAIN_NAME; bind_schannel.utf8_dns_domain.u = cli_credentials_get_realm(gensec_security->credentials); bind_schannel.Flags |= NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME; bind_schannel.utf8_netbios_computer.u = creds->computer_name; } ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel, (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE); if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { status = ndr_map_error2ntstatus(ndr_err); DEBUG(3, ("Could not create schannel bind: %s\n", nt_errstr(status))); return status; } return NT_STATUS_MORE_PROCESSING_REQUIRED; case GENSEC_SERVER: if (state != NULL) { /* no third leg on this protocol */ return NT_STATUS_INVALID_PARAMETER; } /* parse the schannel startup blob */ ndr_err = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel, (ndr_pull_flags_fn_t)ndr_pull_NL_AUTH_MESSAGE); if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { status = ndr_map_error2ntstatus(ndr_err); DEBUG(3, ("Could not parse incoming schannel bind: %s\n", nt_errstr(status))); return status; } if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_DOMAIN_NAME) { domain = bind_schannel.oem_netbios_domain.a; if (strcasecmp_m(domain, lpcfg_workgroup(gensec_security->settings->lp_ctx)) != 0) { DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n", domain, lpcfg_workgroup(gensec_security->settings->lp_ctx))); return NT_STATUS_LOGON_FAILURE; } } else if (bind_schannel.Flags & NL_FLAG_UTF8_DNS_DOMAIN_NAME) { domain = bind_schannel.utf8_dns_domain.u; if (strcasecmp_m(domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx)) != 0) { DEBUG(3, ("Request for schannel to incorrect domain: %s != our domain %s\n", domain, lpcfg_dnsdomain(gensec_security->settings->lp_ctx))); return NT_STATUS_LOGON_FAILURE; } } else { DEBUG(3, ("Request for schannel to without domain\n")); return NT_STATUS_LOGON_FAILURE; } if (bind_schannel.Flags & NL_FLAG_OEM_NETBIOS_COMPUTER_NAME) { workstation = bind_schannel.oem_netbios_computer.a; } else if (bind_schannel.Flags & NL_FLAG_UTF8_NETBIOS_COMPUTER_NAME) { workstation = bind_schannel.utf8_netbios_computer.u; } else { DEBUG(3, ("Request for schannel to without netbios workstation\n")); return NT_STATUS_LOGON_FAILURE; } status = schannel_get_creds_state(out_mem_ctx, gensec_security->settings->lp_ctx, workstation, &creds); if (!NT_STATUS_IS_OK(status)) { DEBUG(3, ("Could not find session key for attempted schannel connection from %s: %s\n", workstation, nt_errstr(status))); if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) { return NT_STATUS_LOGON_FAILURE; } return status; } state = netsec_create_state(gensec_security, creds, false /* not initiator */); if (state == NULL) { return NT_STATUS_NO_MEMORY; } status = auth_anonymous_user_info_dc(state, lpcfg_netbios_name(gensec_security->settings->lp_ctx), &state->user_info_dc); if (!NT_STATUS_IS_OK(status)) { return status; } bind_schannel_ack.MessageType = NL_NEGOTIATE_RESPONSE; bind_schannel_ack.Flags = 0; bind_schannel_ack.Buffer.dummy = 0x6c0000; /* actually I think * this does not have * any meaning here * - gd */ ndr_err = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack, (ndr_push_flags_fn_t)ndr_push_NL_AUTH_MESSAGE); if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) { status = ndr_map_error2ntstatus(ndr_err); DEBUG(3, ("Could not return schannel bind ack for client %s: %s\n", workstation, nt_errstr(status))); return status; } return NT_STATUS_OK; } return NT_STATUS_INVALID_PARAMETER; } static NTSTATUS schannel_update_recv(struct tevent_req *req, TALLOC_CTX *out_mem_ctx, DATA_BLOB *out) { struct schannel_update_state *state = tevent_req_data(req, struct schannel_update_state); NTSTATUS status; *out = data_blob_null; if (tevent_req_is_nterror(req, &status)) { tevent_req_received(req); return status; } status = state->status; talloc_steal(out_mem_ctx, state->out.data); *out = state->out; tevent_req_received(req); return status; } /** * Returns anonymous credentials for schannel, matching Win2k3. * */ static NTSTATUS schannel_session_info(struct gensec_security *gensec_security, TALLOC_CTX *mem_ctx, struct auth_session_info **_session_info) { struct schannel_state *state = talloc_get_type(gensec_security->private_data, struct schannel_state); struct auth4_context *auth_ctx = gensec_security->auth_context; struct auth_session_info *session_info = NULL; uint32_t session_info_flags = 0; NTSTATUS status; if (auth_ctx == NULL) { DEBUG(0, ("Cannot generate a session_info without the auth_context\n")); return NT_STATUS_INTERNAL_ERROR; } if (auth_ctx->generate_session_info == NULL) { DEBUG(0, ("Cannot generate a session_info without the generate_session_info hook\n")); return NT_STATUS_INTERNAL_ERROR; } if (gensec_security->want_features & GENSEC_FEATURE_UNIX_TOKEN) { session_info_flags |= AUTH_SESSION_INFO_UNIX_TOKEN; } session_info_flags |= AUTH_SESSION_INFO_SIMPLE_PRIVILEGES; status = auth_ctx->generate_session_info( auth_ctx, mem_ctx, state->user_info_dc, state->user_info_dc->info->account_name, session_info_flags, &session_info); if (!NT_STATUS_IS_OK(status)) { return status; } *_session_info = session_info; return NT_STATUS_OK; } /* * Reduce the attack surface by ensuring schannel is not availble when * we are not a DC */ static NTSTATUS schannel_server_start(struct gensec_security *gensec_security) { enum server_role server_role = lpcfg_server_role(gensec_security->settings->lp_ctx); switch (server_role) { case ROLE_DOMAIN_BDC: case ROLE_DOMAIN_PDC: case ROLE_ACTIVE_DIRECTORY_DC: case ROLE_IPA_DC: return NT_STATUS_OK; default: return NT_STATUS_NOT_IMPLEMENTED; } } static NTSTATUS schannel_client_start(struct gensec_security *gensec_security) { return NT_STATUS_OK; } static bool schannel_have_feature(struct gensec_security *gensec_security, uint32_t feature) { if (gensec_security->dcerpc_auth_level >= DCERPC_AUTH_LEVEL_INTEGRITY) { if (feature & GENSEC_FEATURE_SIGN) { return true; } } if (gensec_security->dcerpc_auth_level == DCERPC_AUTH_LEVEL_PRIVACY) { if (feature & GENSEC_FEATURE_SEAL) { return true; } } if (feature & GENSEC_FEATURE_DCE_STYLE) { return true; } if (feature & GENSEC_FEATURE_SIGN_PKT_HEADER) { return true; } return false; } /* unseal a packet */ static NTSTATUS schannel_unseal_packet(struct gensec_security *gensec_security, uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, const DATA_BLOB *sig) { struct schannel_state *state = talloc_get_type_abort(gensec_security->private_data, struct schannel_state); return netsec_incoming_packet(state, true, discard_const_p(uint8_t, data), length, whole_pdu, pdu_length, sig); } /* check the signature on a packet */ static NTSTATUS schannel_check_packet(struct gensec_security *gensec_security, const uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, const DATA_BLOB *sig) { struct schannel_state *state = talloc_get_type_abort(gensec_security->private_data, struct schannel_state); return netsec_incoming_packet(state, false, discard_const_p(uint8_t, data), length, whole_pdu, pdu_length, sig); } /* seal a packet */ static NTSTATUS schannel_seal_packet(struct gensec_security *gensec_security, TALLOC_CTX *mem_ctx, uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, DATA_BLOB *sig) { struct schannel_state *state = talloc_get_type_abort(gensec_security->private_data, struct schannel_state); return netsec_outgoing_packet(state, mem_ctx, true, data, length, whole_pdu, pdu_length, sig); } /* sign a packet */ static NTSTATUS schannel_sign_packet(struct gensec_security *gensec_security, TALLOC_CTX *mem_ctx, const uint8_t *data, size_t length, const uint8_t *whole_pdu, size_t pdu_length, DATA_BLOB *sig) { struct schannel_state *state = talloc_get_type_abort(gensec_security->private_data, struct schannel_state); return netsec_outgoing_packet(state, mem_ctx, false, discard_const_p(uint8_t, data), length, whole_pdu, pdu_length, sig); } static const struct gensec_security_ops gensec_schannel_security_ops = { .name = "schannel", .auth_type = DCERPC_AUTH_TYPE_SCHANNEL, .client_start = schannel_client_start, .server_start = schannel_server_start, .update_send = schannel_update_send, .update_recv = schannel_update_recv, .seal_packet = schannel_seal_packet, .sign_packet = schannel_sign_packet, .check_packet = schannel_check_packet, .unseal_packet = schannel_unseal_packet, .session_info = schannel_session_info, .sig_size = schannel_sig_size, .have_feature = schannel_have_feature, .enabled = true, .priority = GENSEC_SCHANNEL }; _PUBLIC_ NTSTATUS gensec_schannel_init(TALLOC_CTX *ctx) { NTSTATUS ret; ret = gensec_register(ctx, &gensec_schannel_security_ops); if (!NT_STATUS_IS_OK(ret)) { DEBUG(0,("Failed to register '%s' gensec backend!\n", gensec_schannel_security_ops.name)); return ret; } return ret; }