| /* |
| * fs/cifs/cifsencrypt.c |
| * |
| * Copyright (C) International Business Machines Corp., 2005,2006 |
| * 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" |
| #include <linux/ctype.h> |
| #include <linux/random.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); |
| extern void SMBencrypt(unsigned char *passwd, unsigned char *c8, |
| unsigned char *p24); |
| |
| 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_SESS_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 TCP_Server_Info * server, |
| __u32 * pexpected_response_sequence_number) |
| { |
| int rc = 0; |
| char smb_signature[20]; |
| |
| if((cifs_pdu == NULL) || (server == 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(server->sequence_number); |
| cifs_pdu->Signature.Sequence.Reserved = 0; |
| |
| *pexpected_response_sequence_number = server->sequence_number++; |
| server->sequence_number++; |
| spin_unlock(&GlobalMid_Lock); |
| |
| rc = cifs_calculate_signature(cifs_pdu, server->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; |
| } |
| |
| static int cifs_calc_signature2(const struct kvec * iov, int n_vec, |
| const char * key, char * signature) |
| { |
| struct MD5Context context; |
| int i; |
| |
| if((iov == NULL) || (signature == NULL)) |
| return -EINVAL; |
| |
| MD5Init(&context); |
| MD5Update(&context,key,CIFS_SESS_KEY_SIZE+16); |
| for(i=0;i<n_vec;i++) { |
| if(iov[i].iov_base == NULL) { |
| cERROR(1,("null iovec entry")); |
| return -EIO; |
| } else if(iov[i].iov_len == 0) |
| break; /* bail out if we are sent nothing to sign */ |
| /* The first entry includes a length field (which does not get |
| signed that occupies the first 4 bytes before the header */ |
| if(i==0) { |
| if (iov[0].iov_len <= 8 ) /* cmd field at offset 9 */ |
| break; /* nothing to sign or corrupt header */ |
| MD5Update(&context,iov[0].iov_base+4, iov[0].iov_len-4); |
| } else |
| MD5Update(&context,iov[i].iov_base, iov[i].iov_len); |
| } |
| |
| MD5Final(signature,&context); |
| |
| return 0; |
| } |
| |
| |
| int cifs_sign_smb2(struct kvec * iov, int n_vec, struct TCP_Server_Info *server, |
| __u32 * pexpected_response_sequence_number) |
| { |
| int rc = 0; |
| char smb_signature[20]; |
| struct smb_hdr * cifs_pdu = iov[0].iov_base; |
| |
| if((cifs_pdu == NULL) || (server == 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(server->sequence_number); |
| cifs_pdu->Signature.Sequence.Reserved = 0; |
| |
| *pexpected_response_sequence_number = server->sequence_number++; |
| server->sequence_number++; |
| spin_unlock(&GlobalMid_Lock); |
| |
| rc = cifs_calc_signature2(iov, n_vec, server->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_SESS_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; |
| __le16 * 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; |
| if(ses->domainName == NULL) |
| return -EINVAL; /* BB should we use CIFS_LINUX_DOM */ |
| 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->server->mac_signing_key,&ctx); |
| kfree(ucase_buf); |
| kfree(unicode_buf); |
| return 0; |
| } |
| |
| #ifdef CONFIG_CIFS_WEAK_PW_HASH |
| void calc_lanman_hash(struct cifsSesInfo * ses, char * lnm_session_key) |
| { |
| int i; |
| char password_with_pad[CIFS_ENCPWD_SIZE]; |
| |
| if(ses->server == NULL) |
| return; |
| |
| memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
| strncpy(password_with_pad, ses->password, CIFS_ENCPWD_SIZE); |
| |
| if((ses->server->secMode & SECMODE_PW_ENCRYPT) == 0) |
| if(extended_security & CIFSSEC_MAY_PLNTXT) { |
| memcpy(lnm_session_key, password_with_pad, CIFS_ENCPWD_SIZE); |
| return; |
| } |
| |
| /* calculate old style session key */ |
| /* calling toupper is less broken than repeatedly |
| calling nls_toupper would be since that will never |
| work for UTF8, but neither handles multibyte code pages |
| but the only alternative would be converting to UCS-16 (Unicode) |
| (using a routine something like UniStrupr) then |
| uppercasing and then converting back from Unicode - which |
| would only worth doing it if we knew it were utf8. Basically |
| utf8 and other multibyte codepages each need their own strupper |
| function since a byte at a time will ont work. */ |
| |
| for(i = 0; i < CIFS_ENCPWD_SIZE; i++) { |
| password_with_pad[i] = toupper(password_with_pad[i]); |
| } |
| |
| SMBencrypt(password_with_pad, ses->server->cryptKey, lnm_session_key); |
| /* clear password before we return/free memory */ |
| memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
| } |
| #endif /* CIFS_WEAK_PW_HASH */ |
| |
| void setup_ntlmv2_rsp(const struct cifsSesInfo * ses, char * resp_buf) |
| { |
| struct ntlmv2_resp * buf = (struct ntlmv2_resp *)resp_buf; |
| |
| buf->blob_signature = cpu_to_le32(0x00000101); |
| buf->reserved = 0; |
| buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME)); |
| get_random_bytes(&buf->client_chal, sizeof(buf->client_chal)); |
| buf->reserved2 = 0; |
| buf->names[0].type = 0; |
| buf->names[0].length = 0; |
| /* calculate buf->ntlmv2_hash */ |
| } |
| |
| 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->server->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); |
| cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); /* BB removeme BB */ |
| } |