diff options
Diffstat (limited to 'source4/libcli/util/ntlmssp_sign.c')
| -rw-r--r-- | source4/libcli/util/ntlmssp_sign.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/source4/libcli/util/ntlmssp_sign.c b/source4/libcli/util/ntlmssp_sign.c new file mode 100644 index 0000000000..bd6d64d842 --- /dev/null +++ b/source4/libcli/util/ntlmssp_sign.c @@ -0,0 +1,226 @@ +/* + * Unix SMB/CIFS implementation. + * Version 3.0 + * NTLMSSP Signing routines + * Copyright (C) Luke Kenneth Casson Leighton 1996-2001 + * Copyright (C) Andrew Bartlett 2003 + * + * 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 2 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, write to the Free Software Foundation, + * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include "includes.h" + +#define CLI_SIGN "session key to client-to-server signing key magic constant" +#define CLI_SEAL "session key to client-to-server sealing key magic constant" +#define SRV_SIGN "session key to server-to-client signing key magic constant" +#define SRV_SEAL "session key to server-to-client sealing key magic constant" + +static void NTLMSSPcalc_ap( unsigned char *hash, unsigned char *data, int len) +{ + unsigned char index_i = hash[256]; + unsigned char index_j = hash[257]; + int ind; + + for (ind = 0; ind < len; ind++) + { + unsigned char tc; + unsigned char t; + + index_i++; + index_j += hash[index_i]; + + tc = hash[index_i]; + hash[index_i] = hash[index_j]; + hash[index_j] = tc; + + t = hash[index_i] + hash[index_j]; + data[ind] = data[ind] ^ hash[t]; + } + + hash[256] = index_i; + hash[257] = index_j; +} + +static void calc_hash(unsigned char *hash, const char *k2, int k2l) +{ + unsigned char j = 0; + int ind; + + for (ind = 0; ind < 256; ind++) + { + hash[ind] = (unsigned char)ind; + } + + for (ind = 0; ind < 256; ind++) + { + unsigned char tc; + + j += (hash[ind] + k2[ind%k2l]); + + tc = hash[ind]; + hash[ind] = hash[j]; + hash[j] = tc; + } + + hash[256] = 0; + hash[257] = 0; +} + +static void calc_ntlmv2_hash(unsigned char hash[16], char digest[16], + const char encrypted_response[16], + const char *constant) +{ + struct MD5Context ctx3; + + MD5Init(&ctx3); + MD5Update(&ctx3, encrypted_response, 5); + MD5Update(&ctx3, constant, strlen(constant)); + MD5Final(digest, &ctx3); + + calc_hash(hash, digest, 16); +} + +enum ntlmssp_direction { + NTLMSSP_SEND, + NTLMSSP_RECEIVE +}; + +static NTSTATUS ntlmssp_make_packet_signiture(NTLMSSP_CLIENT_STATE *ntlmssp_state, + const uchar *data, size_t length, + enum ntlmssp_direction direction, + DATA_BLOB *sig) +{ + if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) { + HMACMD5Context ctx; + char seq_num[4]; + uchar digest[16]; + SIVAL(seq_num, 0, ntlmssp_state->ntlmssp_seq_num); + + hmac_md5_init_limK_to_64(ntlmssp_state->cli_sign_const, 16, &ctx); + hmac_md5_update(seq_num, 4, &ctx); + hmac_md5_update(data, length, &ctx); + hmac_md5_final(digest, &ctx); + + if (!msrpc_gen(sig, "Bd", digest, sizeof(digest), ntlmssp_state->ntlmssp_seq_num)) { + return NT_STATUS_NO_MEMORY; + } + switch (direction) { + case NTLMSSP_SEND: + NTLMSSPcalc_ap(ntlmssp_state->cli_sign_hash, sig->data, sig->length); + break; + case NTLMSSP_RECEIVE: + NTLMSSPcalc_ap(ntlmssp_state->srv_sign_hash, sig->data, sig->length); + break; + } + } else { + uint32 crc; + crc = crc32_buffer(data, length); + if (!msrpc_gen(sig, "ddd", 0, crc, ntlmssp_state->ntlmssp_seq_num)) { + return NT_STATUS_NO_MEMORY; + } + + NTLMSSPcalc_ap(ntlmssp_state->ntlmssp_hash, sig->data, sig->length); + } + return NT_STATUS_OK; +} + +NTSTATUS ntlmssp_client_sign_packet(NTLMSSP_CLIENT_STATE *ntlmssp_state, + const uchar *data, size_t length, + DATA_BLOB *sig) +{ + ntlmssp_state->ntlmssp_seq_num++; + return ntlmssp_make_packet_signiture(ntlmssp_state, data, length, NTLMSSP_SEND, sig); +} + +/** + * Check the signature of an incoming packet + * @note caller *must* check that the signature is the size it expects + * + */ + +NTSTATUS ntlmssp_client_check_packet(NTLMSSP_CLIENT_STATE *ntlmssp_state, + const uchar *data, size_t length, + const DATA_BLOB *sig) +{ + DATA_BLOB local_sig; + NTSTATUS nt_status; + + if (sig->length < 8) { + DEBUG(0, ("NTLMSSP packet check failed due to short signiture (%u bytes)!\n", + sig->length)); + } + + nt_status = ntlmssp_make_packet_signiture(ntlmssp_state, data, + length, NTLMSSP_RECEIVE, &local_sig); + + if (!NT_STATUS_IS_OK(nt_status)) { + DEBUG(0, ("NTLMSSP packet check failed with %s\n", nt_errstr(nt_status))); + return nt_status; + } + + if (memcmp(sig->data, local_sig.data, MIN(sig->length, local_sig.length)) == 0) { + return NT_STATUS_OK; + } else { + DEBUG(5, ("BAD SIG: wanted signature of\n")); + dump_data(5, local_sig.data, local_sig.length); + + DEBUG(5, ("BAD SIG: got signature of\n")); + dump_data(5, sig->data, sig->length); + + DEBUG(0, ("NTLMSSP packet check failed due to invalid signiture!\n")); + return NT_STATUS_ACCESS_DENIED; + } +} + +/** + Initialise the state for NTLMSSP signing. +*/ +NTSTATUS ntlmssp_client_sign_init(NTLMSSP_CLIENT_STATE *ntlmssp_state) +{ + unsigned char p24[24]; + unsigned char lm_hash[16]; + + if (!ntlmssp_state->lm_resp.data) { + /* can't sign or check signitures yet */ + return NT_STATUS_UNSUCCESSFUL; + } + + E_deshash(ntlmssp_state->password, lm_hash); + + NTLMSSPOWFencrypt(lm_hash, ntlmssp_state->lm_resp.data, p24); + + if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) + { + calc_ntlmv2_hash(ntlmssp_state->cli_sign_hash, ntlmssp_state->cli_sign_const, p24, CLI_SIGN); + calc_ntlmv2_hash(ntlmssp_state->cli_seal_hash, ntlmssp_state->cli_seal_const, p24, CLI_SEAL); + calc_ntlmv2_hash(ntlmssp_state->srv_sign_hash, ntlmssp_state->srv_sign_const, p24, SRV_SIGN); + calc_ntlmv2_hash(ntlmssp_state->srv_seal_hash, ntlmssp_state->srv_seal_const, p24, SRV_SEAL); + } + else + { + char k2[8]; + memcpy(k2, p24, 5); + k2[5] = 0xe5; + k2[6] = 0x38; + k2[7] = 0xb0; + + calc_hash(ntlmssp_state->ntlmssp_hash, k2, 8); + } + + ntlmssp_state->ntlmssp_seq_num = 0; + + ZERO_STRUCT(lm_hash); + return NT_STATUS_OK; +} |