From 3979877e5606ecc58c5a31bd0078c6d80ba9cbe7 Mon Sep 17 00:00:00 2001 From: Steve French Date: Wed, 31 May 2006 22:40:51 +0000 Subject: [CIFS] Support for setting up SMB sessions to legacy lanman servers --- fs/cifs/sess.c | 511 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 511 insertions(+) create mode 100644 fs/cifs/sess.c (limited to 'fs/cifs/sess.c') diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c new file mode 100644 index 000000000000..34998416eb73 --- /dev/null +++ b/fs/cifs/sess.c @@ -0,0 +1,511 @@ +/* + * fs/cifs/sess.c + * + * SMB/CIFS session setup handling routines + * + * Copyright (c) International Business Machines Corp., 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 "cifspdu.h" +#include "cifsglob.h" +#include "cifsproto.h" +#include "cifs_unicode.h" +#include "cifs_debug.h" +#include "ntlmssp.h" +#include "nterr.h" +#include + +extern void SMBencrypt(unsigned char *passwd, unsigned char *c8, + unsigned char *p24); + +extern void SMBNTencrypt(unsigned char *passwd, unsigned char *c8, + unsigned char *p24); + +#ifdef CONFIG_CIFS_EXPERIMENTAL + +static __u32 cifs_ssetup_hdr(struct cifsSesInfo *ses, SESSION_SETUP_ANDX *pSMB) +{ + __u32 capabilities = 0; + + /* init fields common to all four types of SessSetup */ + /* note that header is initialized to zero in header_assemble */ + pSMB->req.AndXCommand = 0xFF; + pSMB->req.MaxBufferSize = cpu_to_le16(ses->server->maxBuf); + pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq); + + /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */ + + /* BB verify whether signing required on neg or just on auth frame + (and NTLM case) */ + + capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS | + CAP_LARGE_WRITE_X | CAP_LARGE_READ_X; + + if(ses->server->secMode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) + pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE; + + if (ses->capabilities & CAP_UNICODE) { + pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE; + capabilities |= CAP_UNICODE; + } + if (ses->capabilities & CAP_STATUS32) { + pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS; + capabilities |= CAP_STATUS32; + } + if (ses->capabilities & CAP_DFS) { + pSMB->req.hdr.Flags2 |= SMBFLG2_DFS; + capabilities |= CAP_DFS; + } + if (ses->capabilities & CAP_UNIX) { + capabilities |= CAP_UNIX; + } + + /* BB check whether to init vcnum BB */ + return capabilities; +} + +void unicode_ssetup_strings(char ** pbcc_area, struct cifsSesInfo *ses, + const struct nls_table * nls_cp) +{ + char * bcc_ptr = *pbcc_area; + int bytes_ret = 0; + + /* BB FIXME add check that strings total less + than 335 or will need to send them as arrays */ + + /* align unicode strings, must be word aligned */ + if ((long) bcc_ptr % 2) { + *bcc_ptr = 0; + bcc_ptr++; + } + /* copy user */ + if(ses->userName == NULL) { + /* BB what about null user mounts - check that we do this BB */ + } else { /* 300 should be long enough for any conceivable user name */ + bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->userName, + 300, nls_cp); + } + bcc_ptr += 2 * bytes_ret; + bcc_ptr += 2; /* account for null termination */ + /* copy domain */ + if(ses->domainName == NULL) + bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, + "CIFS_LINUX_DOM", 32, nls_cp); + else + bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->domainName, + 256, nls_cp); + bcc_ptr += 2 * bytes_ret; + bcc_ptr += 2; /* account for null terminator */ + + /* Copy OS version */ + bytes_ret = cifs_strtoUCS((__le16 *)bcc_ptr, "Linux version ", 32, + nls_cp); + bcc_ptr += 2 * bytes_ret; + bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, system_utsname.release, + 32, nls_cp); + bcc_ptr += 2 * bytes_ret; + bcc_ptr += 2; /* trailing null */ + + bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS, + 32, nls_cp); + bcc_ptr += 2 * bytes_ret; + bcc_ptr += 2; /* trailing null */ + + *pbcc_area = bcc_ptr; +} + +void ascii_ssetup_strings(char ** pbcc_area, struct cifsSesInfo *ses, + const struct nls_table * nls_cp) +{ + char * bcc_ptr = *pbcc_area; + + /* copy user */ + /* BB what about null user mounts - check that we do this BB */ + /* copy user */ + if(ses->userName == NULL) { + /* BB what about null user mounts - check that we do this BB */ + } else { /* 300 should be long enough for any conceivable user name */ + strncpy(bcc_ptr, ses->userName, 300); + } + /* BB improve check for overflow */ + bcc_ptr += strnlen(ses->userName, 200); + *bcc_ptr = 0; + bcc_ptr++; /* account for null termination */ + + /* copy domain */ + + if(ses->domainName == NULL) { + strcpy(bcc_ptr, "CIFS_LINUX_DOM"); + bcc_ptr += 14; /* strlen(CIFS_LINUX_DOM) */ + } else { + strncpy(bcc_ptr, ses->domainName, 256); + bcc_ptr += strnlen(ses->domainName, 256); + } + *bcc_ptr = 0; + bcc_ptr++; + + /* BB check for overflow here */ + + strcpy(bcc_ptr, "Linux version "); + bcc_ptr += strlen("Linux version "); + strcpy(bcc_ptr, system_utsname.release); + bcc_ptr += strlen(system_utsname.release) + 1; + + strcpy(bcc_ptr, CIFS_NETWORK_OPSYS); + bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1; + + *pbcc_area = bcc_ptr; +} + +int decode_unicode_ssetup(char ** pbcc_area, int bleft, struct cifsSesInfo *ses, + const struct nls_table * nls_cp) +{ + int rc = 0; + int words_left, len; + char * data = *pbcc_area; + + + + cFYI(1,("bleft %d",bleft)); + + + /* word align, if bytes remaining is not even */ + if(bleft % 2) { + bleft--; + data++; + } + words_left = bleft / 2; + + /* save off server operating system */ + len = UniStrnlen((wchar_t *) data, words_left); + +/* We look for obvious messed up bcc or strings in response so we do not go off + the end since (at least) WIN2K and Windows XP have a major bug in not null + terminating last Unicode string in response */ + if(len >= words_left) + return rc; + + if(ses->serverOS) + kfree(ses->serverOS); + /* UTF-8 string will not grow more than four times as big as UCS-16 */ + ses->serverOS = kzalloc(4 * len, GFP_KERNEL); + if(ses->serverOS != NULL) { + cifs_strfromUCS_le(ses->serverOS, (__le16 *)data, len, + nls_cp); + } + data += 2 * (len + 1); + words_left -= len + 1; + + /* save off server network operating system */ + len = UniStrnlen((wchar_t *) data, words_left); + + if(len >= words_left) + return rc; + + if(ses->serverNOS) + kfree(ses->serverNOS); + ses->serverNOS = kzalloc(4 * len, GFP_KERNEL); /* BB this is wrong length FIXME BB */ + if(ses->serverNOS != NULL) { + cifs_strfromUCS_le(ses->serverNOS, (__le16 *)data, len, + nls_cp); + if(strncmp(ses->serverNOS, "NT LAN Manager 4",16) == 0) { + cFYI(1,("NT4 server")); + ses->flags |= CIFS_SES_NT4; + } + } + data += 2 * (len + 1); + words_left -= len + 1; + + /* save off server domain */ + len = UniStrnlen((wchar_t *) data, words_left); + + if(len > words_left) + return rc; + + if(ses->serverDomain) + kfree(ses->serverDomain); + ses->serverDomain = kzalloc(2 * (len + 1), GFP_KERNEL); /* BB FIXME wrong length */ + if(ses->serverDomain != NULL) { + cifs_strfromUCS_le(ses->serverDomain, (__le16 *)data, len, + nls_cp); + ses->serverDomain[2*len] = 0; + ses->serverDomain[(2*len) + 1] = 0; + } + data += 2 * (len + 1); + words_left -= len + 1; + + cFYI(1,("words left: %d",words_left)); + + return rc; +} + +int decode_ascii_ssetup(char ** pbcc_area, int bleft, struct cifsSesInfo *ses, + const struct nls_table * nls_cp) +{ + int rc = 0; + int len; + char * bcc_ptr = *pbcc_area; + + cFYI(1,("decode sessetup ascii. bleft %d", bleft)); + + len = strnlen(bcc_ptr, bleft); + if(len >= bleft) + return rc; + + if(ses->serverOS) + kfree(ses->serverOS); + + ses->serverOS = kzalloc(len + 1, GFP_KERNEL); + if(ses->serverOS) + strncpy(ses->serverOS, bcc_ptr, len); + + bcc_ptr += len + 1; + bleft -= len + 1; + + len = strnlen(bcc_ptr, bleft); + if(len >= bleft) + return rc; + + if(ses->serverNOS) + kfree(ses->serverNOS); + + ses->serverNOS = kzalloc(len + 1, GFP_KERNEL); + if(ses->serverNOS) + strncpy(ses->serverNOS, bcc_ptr, len); + + bcc_ptr += len + 1; + bleft -= len + 1; + + len = strnlen(bcc_ptr, bleft); + if(len > bleft) + return rc; + + if(ses->serverDomain) + kfree(ses->serverDomain); + + ses->serverDomain = kzalloc(len + 1, GFP_KERNEL); + if(ses->serverOS) + strncpy(ses->serverOS, bcc_ptr, len); + + bcc_ptr += len + 1; + bleft -= len + 1; + + cFYI(1,("ascii: bytes left %d",bleft)); + + return rc; +} + +int +CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses, int first_time, + const struct nls_table *nls_cp) +{ + int rc = 0; + int wct; + int i; + struct smb_hdr *smb_buf; + char *bcc_ptr; + SESSION_SETUP_ANDX *pSMB; + __u32 capabilities; + int count; + int resp_buf_type = 0; + struct kvec iov[1]; + enum securityEnum type; + __u16 action; + int bytes_remaining; + + if(ses == NULL) + return -EINVAL; + + type = ses->server->secType; + if(type == LANMAN) { +#ifndef CONFIG_CIFS_WEAK_PW_HASH + /* LANMAN and plaintext are less secure and off by default. + So we make this explicitly be turned on in kconfig (in the + build) and turned on at runtime (changed from the default) + in proc/fs/cifs or via mount parm. Unfortunately this is + needed for old Win (e.g. Win95), some obscure NAS and OS/2 */ + return -EOPNOTSUPP; +#endif + wct = 10; /* lanman 2 style sessionsetup */ + } else if(type == NTLM) /* NTLMv2 may retry NTLM */ + wct = 13; /* old style NTLM sessionsetup */ + else /* same size for negotiate or auth, NTLMSSP or extended security */ + wct = 12; + + rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses, + (void **)&smb_buf); + if(rc) + return rc; + + pSMB = (SESSION_SETUP_ANDX *)smb_buf; + + capabilities = cifs_ssetup_hdr(ses, pSMB); + bcc_ptr = pByteArea(smb_buf); + + if(type == LANMAN) { +#ifdef CONFIG_CIFS_WEAK_PW_HASH + char lnm_session_key[CIFS_SESSION_KEY_SIZE]; + char password_with_pad[CIFS_ENCPWD_SIZE]; + + /* no capabilities flags in old lanman negotiation */ + + pSMB->old_req.PasswordLength = CIFS_SESSION_KEY_SIZE; + /* BB calculate hash with password */ + /* and copy into bcc */ + + memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); + strncpy(password_with_pad, ses->password, CIFS_ENCPWD_SIZE); + + /* calculate old style session key */ + /* toupper may be less broken then repeatedly calling + nls_toupper would be, but neither handles multibyte code pages + but the only alternative would be converting to UCS-16 (Unicode) + uppercasing and converting back which is only worth doing if + we knew it were utf8. utf8 code page needs its own + toupper and tolower and strnicmp functions */ + + 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); + +#ifdef CONFIG_CIFS_DEBUG2 + cifs_dump_mem("cryptkey: ",ses->server->cryptKey, + CIFS_SESSION_KEY_SIZE); +#endif + /* clear password before we return/free memory */ + memset(password_with_pad, 0, CIFS_ENCPWD_SIZE); + memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_SESSION_KEY_SIZE); + bcc_ptr += CIFS_SESSION_KEY_SIZE; + + /* can not sign if LANMAN negotiated so no need + to calculate signing key? but what if server + changed to do higher than lanman dialect and + we reconnected would we ever calc signing_key? */ + + cERROR(1,("Negotiating LANMAN setting up strings")); + /* Unicode not allowed for LANMAN dialects */ + ascii_ssetup_strings(&bcc_ptr, ses, nls_cp); +#endif + } else if (type == NTLM) { + char ntlm_session_key[CIFS_SESSION_KEY_SIZE]; + + pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities); + pSMB->req_no_secext.CaseInsensitivePasswordLength = + cpu_to_le16(CIFS_SESSION_KEY_SIZE); + pSMB->req_no_secext.CaseSensitivePasswordLength = + cpu_to_le16(CIFS_SESSION_KEY_SIZE); + + /* calculate session key */ + SMBNTencrypt(ses->password, ses->server->cryptKey, + ntlm_session_key); + + if(first_time) /* should this be moved into common code + with similar ntlmv2 path? */ + cifs_calculate_mac_key( + ses->server->mac_signing_key, + ntlm_session_key, ses->password); + /* copy session key */ + + memcpy(bcc_ptr, (char *)ntlm_session_key,CIFS_SESSION_KEY_SIZE); + bcc_ptr += CIFS_SESSION_KEY_SIZE; + memcpy(bcc_ptr, (char *)ntlm_session_key,CIFS_SESSION_KEY_SIZE); + bcc_ptr += CIFS_SESSION_KEY_SIZE; + if(ses->capabilities & CAP_UNICODE) + unicode_ssetup_strings(&bcc_ptr, ses, nls_cp); + else + ascii_ssetup_strings(&bcc_ptr, ses, nls_cp); + } else /* NTLMSSP or SPNEGO */ { + pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC; + capabilities |= CAP_EXTENDED_SECURITY; + pSMB->req.Capabilities = cpu_to_le32(capabilities); + /* BB set password lengths */ + } + + count = (long) bcc_ptr - (long) pByteArea(smb_buf); + smb_buf->smb_buf_length += count; + + /* if we switch to small buffers, count will need to be fewer + than 383 (strings less than 335 bytes) */ + + BCC_LE(smb_buf) = cpu_to_le16(count); + + + /* BB FIXME check for other non ntlm code paths */ + + /* BB check is this too big for a small smb? */ + + iov[0].iov_base = (char *)pSMB; + iov[0].iov_len = smb_buf->smb_buf_length + 4; + + rc = SendReceive2(xid, ses, iov, 1 /* num_iovecs */, &resp_buf_type, 0); + /* SMB request buf freed in SendReceive2 */ + + cFYI(1,("ssetup rc from sendrecv2 is %d",rc)); + if(rc) + goto ssetup_exit; + + pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base; + smb_buf = (struct smb_hdr *)iov[0].iov_base; + + if((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) { + rc = -EIO; + cERROR(1,("bad word count %d", smb_buf->WordCount)); + goto ssetup_exit; + } + action = le16_to_cpu(pSMB->resp.Action); + if (action & GUEST_LOGIN) + cFYI(1, (" Guest login")); /* BB mark SesInfo struct? */ + ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */ + cFYI(1, ("UID = %d ", ses->Suid)); + /* response can have either 3 or 4 word count - Samba sends 3 */ + /* and lanman response is 3 */ + bytes_remaining = BCC(smb_buf); + bcc_ptr = pByteArea(smb_buf); + + if(smb_buf->WordCount == 4) { + __u16 blob_len; + blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength); + bcc_ptr += blob_len; + if(blob_len > bytes_remaining) { + cERROR(1,("bad security blob length %d", blob_len)); + rc = -EINVAL; + goto ssetup_exit; + } + bytes_remaining -= blob_len; + } + + /* BB check if Unicode and decode strings */ + if(smb_buf->Flags2 & SMBFLG2_UNICODE) + rc = decode_unicode_ssetup(&bcc_ptr, bytes_remaining, + ses, nls_cp); + else + rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,nls_cp); + +ssetup_exit: + if(resp_buf_type == CIFS_SMALL_BUFFER) { + cFYI(1,("ssetup freeing small buf %p", iov[0].iov_base)); + cifs_small_buf_release(iov[0].iov_base); + } else if(resp_buf_type == CIFS_LARGE_BUFFER) + cifs_buf_release(iov[0].iov_base); + + return rc; +} +#endif /* CONFIG_CIFS_EXPERIMENTAL */ -- cgit v1.2.3