1 files changed, 99 insertions, 1 deletions

diff --git a/source3/libsmb/smbencrypt.c b/source3/libsmb/smbencrypt.c
index 28160d9609..aa9391325f 100644
--- a/source3/libsmb/smbencrypt.c
+++ b/source3/libsmb/smbencrypt.c
@@ -295,7 +295,7 @@ void SMBsesskeygen_ntv1(const uchar kr[16],
 #endif
 }
 
-static DATA_BLOB NTLMv2_generate_response(uchar ntlm_v2_hash[16],
+DATA_BLOB NTLMv2_generate_response(uchar ntlm_v2_hash[16],
 				   DATA_BLOB server_chal, size_t client_chal_length)
 {
 	uchar ntlmv2_response[16];
@@ -416,3 +416,101 @@ BOOL decode_pw_buffer(char in_buffer[516], char *new_pwrd,
 	
 	return True;
 }
+
+/***********************************************************
+ SMB signing - setup the MAC key.
+************************************************************/
+
+void cli_calculate_mac_key(struct cli_state *cli, const uchar user_session_key[16], const DATA_BLOB response)
+{
+	
+	memcpy(&cli->sign_info.mac_key[0], user_session_key, 16);
+	memcpy(&cli->sign_info.mac_key[16],response.data, MIN(response.length, 40 - 16));
+	cli->sign_info.mac_key_len = MIN(response.length + 16, 40);
+	cli->sign_info.use_smb_signing = True;
+
+	/* These calls are INCONPATIBLE with SMB signing */
+	cli->readbraw_supported = False;
+	cli->writebraw_supported = False;
+
+	/* Reset the sequence number in case we had a previous (aborted) attempt */
+	cli->sign_info.send_seq_num = 2;
+}
+
+/***********************************************************
+ SMB signing - calculate a MAC to send.
+************************************************************/
+
+void cli_caclulate_sign_mac(struct cli_state *cli)
+{
+	unsigned char calc_md5_mac[16];
+	struct MD5Context md5_ctx;
+
+	if (cli->sign_info.temp_smb_signing) {
+		memcpy(&cli->outbuf[smb_ss_field], "SignRequest", 8);
+		cli->sign_info.temp_smb_signing = False;
+		return;
+	}
+
+	if (!cli->sign_info.use_smb_signing) {
+		return;
+	}
+
+	/*
+	 * Firstly put the sequence number into the first 4 bytes.
+	 * and zero out the next 4 bytes.
+	 */
+	SIVAL(cli->outbuf, smb_ss_field, cli->sign_info.send_seq_num);
+	SIVAL(cli->outbuf, smb_ss_field + 4, 0);
+
+	/* Calculate the 16 byte MAC and place first 8 bytes into the field. */
+	MD5Init(&md5_ctx);
+	MD5Update(&md5_ctx, cli->sign_info.mac_key, cli->sign_info.mac_key_len);
+	MD5Update(&md5_ctx, cli->outbuf + 4, smb_len(cli->outbuf));
+	MD5Final(calc_md5_mac, &md5_ctx);
+
+	memcpy(&cli->outbuf[smb_ss_field], calc_md5_mac, 8);
+
+/*	cli->outbuf[smb_ss_field+2]=0; 
+	Uncomment this to test if the remote server actually verifies signitures...*/
+	cli->sign_info.send_seq_num++;
+	cli->sign_info.reply_seq_num = cli->sign_info.send_seq_num;
+	cli->sign_info.send_seq_num++;
+}
+
+/***********************************************************
+ SMB signing - check a MAC sent by server.
+************************************************************/
+
+BOOL cli_check_sign_mac(struct cli_state *cli)
+{
+	unsigned char calc_md5_mac[16];
+	unsigned char server_sent_mac[8];
+	struct MD5Context md5_ctx;
+
+	if (cli->sign_info.temp_smb_signing) {
+		return True;
+	}
+
+	if (!cli->sign_info.use_smb_signing) {
+		return True;
+	}
+
+	/*
+	 * Firstly put the sequence number into the first 4 bytes.
+	 * and zero out the next 4 bytes.
+	 */
+
+	memcpy(server_sent_mac, &cli->inbuf[smb_ss_field], sizeof(server_sent_mac));
+
+	SIVAL(cli->inbuf, smb_ss_field, cli->sign_info.reply_seq_num);
+	SIVAL(cli->inbuf, smb_ss_field + 4, 0);
+
+	/* Calculate the 16 byte MAC and place first 8 bytes into the field. */
+	MD5Init(&md5_ctx);
+	MD5Update(&md5_ctx, cli->sign_info.mac_key, cli->sign_info.mac_key_len);
+	MD5Update(&md5_ctx, cli->inbuf + 4, smb_len(cli->inbuf));
+	MD5Final(calc_md5_mac, &md5_ctx);
+
+	return (memcmp(server_sent_mac, calc_md5_mac, 8) == 0);
+}