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* ntlm proxy support for OpenVPN
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* Copyright (C) 2004 William Preston
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* *NTLMv2 support and domain name parsing by Miroslav Zajic, Nextsoft s.r.o.*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program (see the file COPYING included with this
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* distribution); if not, write to the Free Software Foundation, Inc.,
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* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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/* 64bit datatype macros */
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# define UINTEGER64 __int64
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# define UINT64(c) c ## Ui64
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/* Non MS compilers */
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# define UINTEGER64 unsigned long long
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# define UINT64(c) c ## LL
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create_des_keys(const unsigned char *hash, unsigned char *key)
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key[1] = ((hash[0]&1)<<7)|(hash[1]>>1);
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key[2] = ((hash[1]&3)<<6)|(hash[2]>>2);
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key[3] = ((hash[2]&7)<<5)|(hash[3]>>3);
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key[4] = ((hash[3]&15)<<4)|(hash[4]>>4);
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key[5] = ((hash[4]&31)<<3)|(hash[5]>>5);
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key[6] = ((hash[5]&63)<<2)|(hash[6]>>6);
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key[7] = ((hash[6]&127)<<1);
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des_set_odd_parity((des_cblock *)key);
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gen_md4_hash (const char* data, int data_len, char *result)
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/* result is 16 byte md4 hash */
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MD4_Update (&c, data, data_len);
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MD4_Final ((unsigned char *)md, &c);
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memcpy (result, md, 16);
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gen_hmac_md5 (const char* data, int data_len, const char* key, int key_len,char *result)
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HMAC_Init (&c, key, key_len, EVP_md5());
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HMAC_Update (&c, (const unsigned char *)data, data_len);
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HMAC_Final (&c, (unsigned char *)result, &len);
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gen_timestamp (unsigned char *timestamp)
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/* Copies 8 bytes long timestamp into "timestamp" buffer.
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* Timestamp is Little-endian, 64-bit signed value representing the number of tenths of a microsecond since January 1, 1601.
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UINTEGER64 timestamp_ull;
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timestamp_ull = openvpn_time(NULL);
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timestamp_ull = (timestamp_ull + UINT64(11644473600)) * UINT64(10000000);
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/* store little endian value */
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timestamp[0]= timestamp_ull & UINT64(0xFF);
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timestamp[1]= (timestamp_ull >> 8) & UINT64(0xFF);
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timestamp[2]= (timestamp_ull >> 16) & UINT64(0xFF);
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timestamp[3]= (timestamp_ull >> 24) & UINT64(0xFF);
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timestamp[4]= (timestamp_ull >> 32) & UINT64(0xFF);
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timestamp[5]= (timestamp_ull >> 40) & UINT64(0xFF);
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timestamp[6]= (timestamp_ull >> 48) & UINT64(0xFF);
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timestamp[7]= (timestamp_ull >> 56) & UINT64(0xFF);
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gen_nonce (unsigned char *nonce)
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/* Generates 8 random bytes to be used as client nonce */
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nonce[i] = (unsigned char)get_random();
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unsigned char *my_strupr(unsigned char *str)
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/* converts string to uppercase in place */
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unsigned char *tmp = str;;
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do *str = toupper(*str); while (*(++str));
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unicodize (char *dst, const char *src)
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/* not really unicode... */
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add_security_buffer(int sb_offset, void *data, int length, unsigned char *msg_buf, int *msg_bufpos)
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/* Adds security buffer data to a message and sets security buffer's offset and length */
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msg_buf[sb_offset] = (unsigned char)length;
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msg_buf[sb_offset + 2] = msg_buf[sb_offset];
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msg_buf[sb_offset + 4] = (unsigned char)(*msg_bufpos & 0xff);
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msg_buf[sb_offset + 5] = (unsigned char)((*msg_bufpos >> 8) & 0xff);
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memcpy(&msg_buf[*msg_bufpos], data, msg_buf[sb_offset]);
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*msg_bufpos += length;
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ntlm_phase_1 (const struct http_proxy_info *p, struct gc_arena *gc)
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struct buffer out = alloc_buf_gc (96, gc);
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/* try a minimal NTLM handshake
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* http://davenport.sourceforge.net/ntlm.html
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* This message contains only the NTLMSSP signature,
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* the NTLM message type,
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* and the minimal set of flags (Negotiate NTLM and Negotiate OEM).
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buf_printf (&out, "%s", "TlRMTVNTUAABAAAAAgIAAA==");
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return (BSTR (&out));
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ntlm_phase_3 (const struct http_proxy_info *p, const char *phase_2, struct gc_arena *gc)
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* http://davenport.sourceforge.net/ntlm.html
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char pwbuf[sizeof (p->up.password) * 2]; /* for unicode password */
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char buf2[128]; /* decoded reply from proxy */
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unsigned char phase3[464];
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char challenge[8], ntlm_response[24];
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des_cblock key1, key2, key3;
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des_key_schedule sched1, sched2, sched3;
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char ntlmv2_response[144];
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char userdomain_u[256]; /* for uppercase unicode username and domain */
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char userdomain[128]; /* the same as previous but ascii */
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char ntlmv2_hash[16];
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char ntlmv2_hmacmd5[16];
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char *ntlmv2_blob = ntlmv2_response + 16; /* inside ntlmv2_response, length: 128 */
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int ntlmv2_blob_size=0;
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int phase3_bufpos = 0x40; /* offset to next security buffer data to be added */
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bool ntlmv2_enabled = (p->auth_method == HTTP_AUTH_NTLM2);
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ASSERT (strlen (p->up.username) > 0);
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ASSERT (strlen (p->up.password) > 0);
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/* username parsing */
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separator = strchr(p->up.username, '\\');
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if (separator == NULL) {
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strncpy(username, p->up.username, sizeof(username)-1);
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username[sizeof(username)-1]=0;
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strncpy(username, separator+1, sizeof(username)-1);
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username[sizeof(username)-1]=0;
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len = separator - p->up.username;
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if (len > sizeof(domain) - 1) len = sizeof(domain) - 1;
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strncpy(domain, p->up.username, len);
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/* fill 1st 16 bytes with md4 hash, disregard terminating null */
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gen_md4_hash (pwbuf, unicodize (pwbuf, p->up.password) - 2, md4_hash);
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/* pad to 21 bytes */
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memset (md4_hash + 16, 0, 5);
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ret_val = base64_decode( phase_2, (void *)buf2);
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/* we can be sure that phase_2 is less than 128
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* therefore buf2 needs to be (3/4 * 128) */
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/* extract the challenge from bytes 24-31 */
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challenge[i] = buf2[i+24];
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if (ntlmv2_enabled){ /* Generate NTLMv2 response */
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my_strupr((unsigned char *)strcpy(userdomain, username));
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if (strlen(username) + strlen(domain) < sizeof(userdomain))
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strcat(userdomain, domain);
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msg (M_INFO, "Warning: Username or domain too long");
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unicodize (userdomain_u, userdomain);
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gen_hmac_md5(userdomain_u, 2 * strlen(userdomain), md4_hash, 16, ntlmv2_hash);
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memset(ntlmv2_blob, 0, 128); /* Clear blob buffer */
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ntlmv2_blob[0x00]=1; /* Signature */
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ntlmv2_blob[0x01]=1; /* Signature */
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ntlmv2_blob[0x04]=0; /* Reserved */
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gen_timestamp((unsigned char *)&ntlmv2_blob[0x08]); /* 64-bit Timestamp */
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gen_nonce((unsigned char *)&ntlmv2_blob[0x10]); /* 64-bit Client Nonce */
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ntlmv2_blob[0x18]=0; /* Unknown, zero should work */
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/* Add target information block to the blob */
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if (( *((long *)&buf2[0x14]) & 0x00800000) == 0x00800000){ /* Check for Target Information block */
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tib_len = buf2[0x28];/* Get Target Information block size */
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if (tib_len > 96) tib_len = 96;
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char *tib_ptr = buf2 + buf2[0x2c]; /* Get Target Information block pointer */
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memcpy(&ntlmv2_blob[0x1c], tib_ptr, tib_len); /* Copy Target Information block into the blob */
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ntlmv2_blob[0x1c + tib_len] = 0; /* Unknown, zero works */
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/* Get blob length */
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ntlmv2_blob_size = 0x20 + tib_len;
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/* Add challenge from message 2 */
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memcpy(&ntlmv2_response[8], challenge, 8);
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gen_hmac_md5(&ntlmv2_response[8], ntlmv2_blob_size + 8, ntlmv2_hash, 16, ntlmv2_hmacmd5);
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/* Add hmac-md5 result to the blob */
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memcpy(ntlmv2_response, ntlmv2_hmacmd5, 16); /* Note: This overwrites challenge previously written at ntlmv2_response[8..15] */
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} else { /* Generate NTLM response */
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create_des_keys ((unsigned char *)md4_hash, key1);
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des_set_key_unchecked ((des_cblock *)key1, sched1);
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des_ecb_encrypt ((des_cblock *)challenge, (des_cblock *)ntlm_response, sched1, DES_ENCRYPT);
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create_des_keys ((unsigned char *)&(md4_hash[7]), key2);
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des_set_key_unchecked ((des_cblock *)key2, sched2);
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des_ecb_encrypt ((des_cblock *)challenge, (des_cblock *)&(ntlm_response[8]), sched2, DES_ENCRYPT);
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create_des_keys ((unsigned char *)&(md4_hash[14]), key3);
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des_set_key_unchecked ((des_cblock *)key3, sched3);
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des_ecb_encrypt ((des_cblock *)challenge, (des_cblock *)&(ntlm_response[16]), sched3, DES_ENCRYPT);
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memset (phase3, 0, sizeof (phase3)); /* clear reply */
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strcpy ((char *)phase3, "NTLMSSP\0"); /* signature */
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phase3[8] = 3; /* type 3 */
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if (ntlmv2_enabled){ /* NTLMv2 response */
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add_security_buffer(0x14, ntlmv2_response, ntlmv2_blob_size + 16, phase3, &phase3_bufpos);
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}else{ /* NTLM response */
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add_security_buffer(0x14, ntlm_response, 24, phase3, &phase3_bufpos);
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/* username in ascii */
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add_security_buffer(0x24, username, strlen (username), phase3, &phase3_bufpos);
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/* Set domain. If <domain> is empty, default domain will be used (i.e. proxy's domain) */
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add_security_buffer(0x1c, domain, strlen (domain), phase3, &phase3_bufpos);
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/* other security buffers will be empty */
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phase3[0x10] = phase3_bufpos; /* lm not used */
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phase3[0x30] = phase3_bufpos; /* no workstation name supplied */
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phase3[0x38] = phase3_bufpos; /* no session key */
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phase3[0x3c] = 0x02; /* negotiate oem */
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phase3[0x3d] = 0x02; /* negotiate ntlm */
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return ((const char *)make_base64_string2 ((unsigned char *)phase3, phase3_bufpos, gc));
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static void dummy(void) {}
added
removed
ntlm.c
