diff options
Diffstat (limited to 'fs/cifs/cifsencrypt.c')
| -rw-r--r-- | fs/cifs/cifsencrypt.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c new file mode 100644 index 000000000000..78829e7d8cd0 --- /dev/null +++ b/fs/cifs/cifsencrypt.c @@ -0,0 +1,209 @@ +/* + * fs/cifs/cifsencrypt.c + * + * Copyright (C) International Business Machines Corp., 2003 + * Author(s): Steve French (sfrench@us.ibm.com) + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 2.1 of the License, or + * (at your option) any later version. + * + * This library 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 Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/fs.h> +#include "cifspdu.h" +#include "cifsglob.h" +#include "cifs_debug.h" +#include "md5.h" +#include "cifs_unicode.h" +#include "cifsproto.h" + +/* Calculate and return the CIFS signature based on the mac key and the smb pdu */ +/* the 16 byte signature must be allocated by the caller */ +/* Note we only use the 1st eight bytes */ +/* Note that the smb header signature field on input contains the + sequence number before this function is called */ + +extern void mdfour(unsigned char *out, unsigned char *in, int n); +extern void E_md4hash(const unsigned char *passwd, unsigned char *p16); + +static int cifs_calculate_signature(const struct smb_hdr * cifs_pdu, const char * key, char * signature) +{ + struct MD5Context context; + + if((cifs_pdu == NULL) || (signature == NULL)) + return -EINVAL; + + MD5Init(&context); + MD5Update(&context,key,CIFS_SESSION_KEY_SIZE+16); + MD5Update(&context,cifs_pdu->Protocol,cifs_pdu->smb_buf_length); + MD5Final(signature,&context); + return 0; +} + +int cifs_sign_smb(struct smb_hdr * cifs_pdu, struct cifsSesInfo * ses, + __u32 * pexpected_response_sequence_number) +{ + int rc = 0; + char smb_signature[20]; + + /* BB remember to initialize sequence number elsewhere and initialize mac_signing key elsewhere BB */ + /* BB remember to add code to save expected sequence number in midQ entry BB */ + + if((cifs_pdu == NULL) || (ses == NULL)) + return -EINVAL; + + if((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0) + return rc; + + spin_lock(&GlobalMid_Lock); + cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(ses->sequence_number); + cifs_pdu->Signature.Sequence.Reserved = 0; + + *pexpected_response_sequence_number = ses->sequence_number++; + ses->sequence_number++; + spin_unlock(&GlobalMid_Lock); + + rc = cifs_calculate_signature(cifs_pdu, ses->mac_signing_key,smb_signature); + if(rc) + memset(cifs_pdu->Signature.SecuritySignature, 0, 8); + else + memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8); + + return rc; +} + +int cifs_verify_signature(struct smb_hdr * cifs_pdu, const char * mac_key, + __u32 expected_sequence_number) +{ + unsigned int rc; + char server_response_sig[8]; + char what_we_think_sig_should_be[20]; + + if((cifs_pdu == NULL) || (mac_key == NULL)) + return -EINVAL; + + if (cifs_pdu->Command == SMB_COM_NEGOTIATE) + return 0; + + if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) { + struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)cifs_pdu; + if(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE) + return 0; + } + + /* BB what if signatures are supposed to be on for session but server does not + send one? BB */ + + /* Do not need to verify session setups with signature "BSRSPYL " */ + if(memcmp(cifs_pdu->Signature.SecuritySignature,"BSRSPYL ",8)==0) + cFYI(1,("dummy signature received for smb command 0x%x",cifs_pdu->Command)); + + /* save off the origiginal signature so we can modify the smb and check + its signature against what the server sent */ + memcpy(server_response_sig,cifs_pdu->Signature.SecuritySignature,8); + + cifs_pdu->Signature.Sequence.SequenceNumber = cpu_to_le32(expected_sequence_number); + cifs_pdu->Signature.Sequence.Reserved = 0; + + rc = cifs_calculate_signature(cifs_pdu, mac_key, + what_we_think_sig_should_be); + + if(rc) + return rc; + + +/* cifs_dump_mem("what we think it should be: ",what_we_think_sig_should_be,16); */ + + if(memcmp(server_response_sig, what_we_think_sig_should_be, 8)) + return -EACCES; + else + return 0; + +} + +/* We fill in key by putting in 40 byte array which was allocated by caller */ +int cifs_calculate_mac_key(char * key, const char * rn, const char * password) +{ + char temp_key[16]; + if ((key == NULL) || (rn == NULL)) + return -EINVAL; + + E_md4hash(password, temp_key); + mdfour(key,temp_key,16); + memcpy(key+16,rn, CIFS_SESSION_KEY_SIZE); + return 0; +} + +int CalcNTLMv2_partial_mac_key(struct cifsSesInfo * ses, struct nls_table * nls_info) +{ + char temp_hash[16]; + struct HMACMD5Context ctx; + char * ucase_buf; + wchar_t * unicode_buf; + unsigned int i,user_name_len,dom_name_len; + + if(ses == NULL) + return -EINVAL; + + E_md4hash(ses->password, temp_hash); + + hmac_md5_init_limK_to_64(temp_hash, 16, &ctx); + user_name_len = strlen(ses->userName); + if(user_name_len > MAX_USERNAME_SIZE) + return -EINVAL; + dom_name_len = strlen(ses->domainName); + if(dom_name_len > MAX_USERNAME_SIZE) + return -EINVAL; + + ucase_buf = kmalloc((MAX_USERNAME_SIZE+1), GFP_KERNEL); + if(ucase_buf == NULL) + return -ENOMEM; + unicode_buf = kmalloc((MAX_USERNAME_SIZE+1)*4, GFP_KERNEL); + if(unicode_buf == NULL) { + kfree(ucase_buf); + return -ENOMEM; + } + + for(i=0;i<user_name_len;i++) + ucase_buf[i] = nls_info->charset2upper[(int)ses->userName[i]]; + ucase_buf[i] = 0; + user_name_len = cifs_strtoUCS(unicode_buf, ucase_buf, MAX_USERNAME_SIZE*2, nls_info); + unicode_buf[user_name_len] = 0; + user_name_len++; + + for(i=0;i<dom_name_len;i++) + ucase_buf[i] = nls_info->charset2upper[(int)ses->domainName[i]]; + ucase_buf[i] = 0; + dom_name_len = cifs_strtoUCS(unicode_buf+user_name_len, ucase_buf, MAX_USERNAME_SIZE*2, nls_info); + + unicode_buf[user_name_len + dom_name_len] = 0; + hmac_md5_update((const unsigned char *) unicode_buf, + (user_name_len+dom_name_len)*2,&ctx); + + hmac_md5_final(ses->mac_signing_key,&ctx); + kfree(ucase_buf); + kfree(unicode_buf); + return 0; +} +void CalcNTLMv2_response(const struct cifsSesInfo * ses,char * v2_session_response) +{ + struct HMACMD5Context context; + memcpy(v2_session_response + 8, ses->server->cryptKey,8); + /* gen_blob(v2_session_response + 16); */ + hmac_md5_init_limK_to_64(ses->mac_signing_key, 16, &context); + + hmac_md5_update(ses->server->cryptKey,8,&context); +/* hmac_md5_update(v2_session_response+16)client thing,8,&context); */ /* BB fix */ + + hmac_md5_final(v2_session_response,&context); +} |