| /* |
| * 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 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, const unsigned char *c8, |
| unsigned char *p24); |
| |
| static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu, |
| const struct mac_key *key, char *signature) |
| { |
| struct MD5Context context; |
| |
| if ((cifs_pdu == NULL) || (signature == NULL) || (key == NULL)) |
| return -EINVAL; |
| |
| cifs_MD5_init(&context); |
| cifs_MD5_update(&context, (char *)&key->data, key->len); |
| cifs_MD5_update(&context, cifs_pdu->Protocol, cifs_pdu->smb_buf_length); |
| |
| cifs_MD5_final(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 struct mac_key *key, char *signature) |
| { |
| struct MD5Context context; |
| int i; |
| |
| if ((iov == NULL) || (signature == NULL) || (key == NULL)) |
| return -EINVAL; |
| |
| cifs_MD5_init(&context); |
| cifs_MD5_update(&context, (char *)&key->data, key->len); |
| for (i = 0; i < n_vec; i++) { |
| if (iov[i].iov_len == 0) |
| continue; |
| if (iov[i].iov_base == NULL) { |
| cERROR(1, ("null iovec entry")); |
| return -EIO; |
| } |
| /* 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 */ |
| cifs_MD5_update(&context, iov[0].iov_base+4, |
| iov[0].iov_len-4); |
| } else |
| cifs_MD5_update(&context, iov[i].iov_base, iov[i].iov_len); |
| } |
| |
| cifs_MD5_final(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 struct mac_key *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(struct mac_key *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->data.ntlm, temp_key, 16); |
| memcpy(key->data.ntlm+16, rn, CIFS_SESS_KEY_SIZE); |
| key->len = 40; |
| return 0; |
| } |
| |
| int CalcNTLMv2_partial_mac_key(struct cifsSesInfo *ses, |
| const 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->ntlmv2_hash, &ctx); |
| kfree(ucase_buf); |
| kfree(unicode_buf); |
| return 0; |
| } |
| |
| #ifdef CONFIG_CIFS_WEAK_PW_HASH |
| void calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt, |
| char *lnm_session_key) |
| { |
| int i; |
| char password_with_pad[CIFS_ENCPWD_SIZE]; |
| |
| memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
| if (password) |
| strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE); |
| |
| if (!encrypt && extended_security & CIFSSEC_MAY_PLNTXT) { |
| memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE); |
| 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, cryptkey, lnm_session_key); |
| |
| /* clear password before we return/free memory */ |
| memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); |
| } |
| #endif /* CIFS_WEAK_PW_HASH */ |
| |
| static int calc_ntlmv2_hash(struct cifsSesInfo *ses, |
| const struct nls_table *nls_cp) |
| { |
| int rc = 0; |
| int len; |
| char nt_hash[16]; |
| struct HMACMD5Context *pctxt; |
| wchar_t *user; |
| wchar_t *domain; |
| |
| pctxt = kmalloc(sizeof(struct HMACMD5Context), GFP_KERNEL); |
| |
| if (pctxt == NULL) |
| return -ENOMEM; |
| |
| /* calculate md4 hash of password */ |
| E_md4hash(ses->password, nt_hash); |
| |
| /* convert Domainname to unicode and uppercase */ |
| hmac_md5_init_limK_to_64(nt_hash, 16, pctxt); |
| |
| /* convert ses->userName to unicode and uppercase */ |
| len = strlen(ses->userName); |
| user = kmalloc(2 + (len * 2), GFP_KERNEL); |
| if (user == NULL) |
| goto calc_exit_2; |
| len = cifs_strtoUCS((__le16 *)user, ses->userName, len, nls_cp); |
| UniStrupr(user); |
| hmac_md5_update((char *)user, 2*len, pctxt); |
| |
| /* convert ses->domainName to unicode and uppercase */ |
| if (ses->domainName) { |
| len = strlen(ses->domainName); |
| |
| domain = kmalloc(2 + (len * 2), GFP_KERNEL); |
| if (domain == NULL) |
| goto calc_exit_1; |
| len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len, |
| nls_cp); |
| /* the following line was removed since it didn't work well |
| with lower cased domain name that passed as an option. |
| Maybe converting the domain name earlier makes sense */ |
| /* UniStrupr(domain); */ |
| |
| hmac_md5_update((char *)domain, 2*len, pctxt); |
| |
| kfree(domain); |
| } |
| calc_exit_1: |
| kfree(user); |
| calc_exit_2: |
| /* BB FIXME what about bytes 24 through 40 of the signing key? |
| compare with the NTLM example */ |
| hmac_md5_final(ses->server->ntlmv2_hash, pctxt); |
| |
| return rc; |
| } |
| |
| void setup_ntlmv2_rsp(struct cifsSesInfo *ses, char *resp_buf, |
| const struct nls_table *nls_cp) |
| { |
| int rc; |
| struct ntlmv2_resp *buf = (struct ntlmv2_resp *)resp_buf; |
| struct HMACMD5Context context; |
| |
| 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 = cpu_to_le16(NTLMSSP_DOMAIN_TYPE); |
| buf->names[0].length = 0; |
| buf->names[1].type = 0; |
| buf->names[1].length = 0; |
| |
| /* calculate buf->ntlmv2_hash */ |
| rc = calc_ntlmv2_hash(ses, nls_cp); |
| if (rc) |
| cERROR(1, ("could not get v2 hash rc %d", rc)); |
| CalcNTLMv2_response(ses, resp_buf); |
| |
| /* now calculate the MAC key for NTLMv2 */ |
| hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context); |
| hmac_md5_update(resp_buf, 16, &context); |
| hmac_md5_final(ses->server->mac_signing_key.data.ntlmv2.key, &context); |
| |
| memcpy(&ses->server->mac_signing_key.data.ntlmv2.resp, resp_buf, |
| sizeof(struct ntlmv2_resp)); |
| ses->server->mac_signing_key.len = 16 + sizeof(struct ntlmv2_resp); |
| } |
| |
| void CalcNTLMv2_response(const struct cifsSesInfo *ses, |
| char *v2_session_response) |
| { |
| struct HMACMD5Context context; |
| /* rest of v2 struct already generated */ |
| memcpy(v2_session_response + 8, ses->server->cryptKey, 8); |
| hmac_md5_init_limK_to_64(ses->server->ntlmv2_hash, 16, &context); |
| |
| hmac_md5_update(v2_session_response+8, |
| sizeof(struct ntlmv2_resp) - 8, &context); |
| |
| hmac_md5_final(v2_session_response, &context); |
| /* cifs_dump_mem("v2_sess_rsp: ", v2_session_response, 32); */ |
| } |