mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-24 11:29:10 +00:00
190b2c4f8a
attacks and is required to connect to Windows 2003 servers in their default configuration. This adds an extra field to the SMB header containing the truncated 64-bit MD5 digest of a key (a function of the user's password and the server's authentication challenge), an implicit sequence number, and the message data itself. As signing each message imposes a significant performance penalty, we only enable it if the server will not let us connect without it; this should eventually become an option to mount_smbfs.
340 lines
9.0 KiB
C
340 lines
9.0 KiB
C
/*
|
|
* Copyright (c) 2000-2001, Boris Popov
|
|
* All rights reserved.
|
|
*
|
|
* Copyright (c) 2003, 2004 Tim J. Robbins.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by Boris Popov.
|
|
* 4. Neither the name of the author nor the names of any co-contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/socketvar.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/endian.h>
|
|
#include <sys/mbuf.h>
|
|
#include <sys/mchain.h>
|
|
#include <sys/md4.h>
|
|
#include <sys/md5.h>
|
|
#include <sys/iconv.h>
|
|
|
|
#include <netsmb/smb.h>
|
|
#include <netsmb/smb_conn.h>
|
|
#include <netsmb/smb_subr.h>
|
|
#include <netsmb/smb_rq.h>
|
|
#include <netsmb/smb_dev.h>
|
|
|
|
#include "opt_netsmb.h"
|
|
|
|
#ifdef NETSMBCRYPTO
|
|
|
|
#include <crypto/des/des.h>
|
|
|
|
static u_char N8[] = {0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25};
|
|
|
|
|
|
static void
|
|
smb_E(const u_char *key, u_char *data, u_char *dest)
|
|
{
|
|
des_key_schedule *ksp;
|
|
u_char kk[8];
|
|
|
|
kk[0] = key[0] & 0xfe;
|
|
kk[1] = key[0] << 7 | (key[1] >> 1 & 0xfe);
|
|
kk[2] = key[1] << 6 | (key[2] >> 2 & 0xfe);
|
|
kk[3] = key[2] << 5 | (key[3] >> 3 & 0xfe);
|
|
kk[4] = key[3] << 4 | (key[4] >> 4 & 0xfe);
|
|
kk[5] = key[4] << 3 | (key[5] >> 5 & 0xfe);
|
|
kk[6] = key[5] << 2 | (key[6] >> 6 & 0xfe);
|
|
kk[7] = key[6] << 1;
|
|
ksp = malloc(sizeof(des_key_schedule), M_SMBTEMP, M_WAITOK);
|
|
des_set_key((des_cblock *)kk, *ksp);
|
|
des_ecb_encrypt((des_cblock *)data, (des_cblock *)dest, *ksp, 1);
|
|
free(ksp, M_SMBTEMP);
|
|
}
|
|
#endif
|
|
|
|
|
|
int
|
|
smb_encrypt(const u_char *apwd, u_char *C8, u_char *RN)
|
|
{
|
|
#ifdef NETSMBCRYPTO
|
|
u_char *p, *P14, *S21;
|
|
|
|
p = malloc(14 + 21, M_SMBTEMP, M_WAITOK);
|
|
bzero(p, 14 + 21);
|
|
P14 = p;
|
|
S21 = p + 14;
|
|
bcopy(apwd, P14, min(14, strlen(apwd)));
|
|
/*
|
|
* S21 = concat(Ex(P14, N8), zeros(5));
|
|
*/
|
|
smb_E(P14, N8, S21);
|
|
smb_E(P14 + 7, N8, S21 + 8);
|
|
|
|
smb_E(S21, C8, RN);
|
|
smb_E(S21 + 7, C8, RN + 8);
|
|
smb_E(S21 + 14, C8, RN + 16);
|
|
free(p, M_SMBTEMP);
|
|
return 0;
|
|
#else
|
|
SMBERROR("password encryption is not available\n");
|
|
bzero(RN, 24);
|
|
return EAUTH;
|
|
#endif
|
|
}
|
|
|
|
int
|
|
smb_ntencrypt(const u_char *apwd, u_char *C8, u_char *RN)
|
|
{
|
|
#ifdef NETSMBCRYPTO
|
|
u_char S21[21];
|
|
u_int16_t *unipwd;
|
|
MD4_CTX *ctxp;
|
|
int len;
|
|
|
|
len = strlen(apwd);
|
|
unipwd = malloc((len + 1) * sizeof(u_int16_t), M_SMBTEMP, M_WAITOK);
|
|
/*
|
|
* S21 = concat(MD4(U(apwd)), zeros(5));
|
|
*/
|
|
smb_strtouni(unipwd, apwd);
|
|
ctxp = malloc(sizeof(MD4_CTX), M_SMBTEMP, M_WAITOK);
|
|
MD4Init(ctxp);
|
|
MD4Update(ctxp, (u_char*)unipwd, len * sizeof(u_int16_t));
|
|
free(unipwd, M_SMBTEMP);
|
|
bzero(S21, 21);
|
|
MD4Final(S21, ctxp);
|
|
free(ctxp, M_SMBTEMP);
|
|
|
|
smb_E(S21, C8, RN);
|
|
smb_E(S21 + 7, C8, RN + 8);
|
|
smb_E(S21 + 14, C8, RN + 16);
|
|
return 0;
|
|
#else
|
|
SMBERROR("password encryption is not available\n");
|
|
bzero(RN, 24);
|
|
return EAUTH;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Calculate message authentication code (MAC) key for virtual circuit.
|
|
*/
|
|
int
|
|
smb_calcmackey(struct smb_vc *vcp)
|
|
{
|
|
#ifdef NETSMBCRYPTO
|
|
const char *pwd;
|
|
u_int16_t *unipwd;
|
|
int len;
|
|
MD4_CTX md4;
|
|
u_char S16[16], S21[21];
|
|
|
|
KASSERT(vcp->vc_hflags2 & SMB_FLAGS2_SECURITY_SIGNATURE,
|
|
("signatures not enabled"));
|
|
|
|
if (vcp->vc_mackey != NULL) {
|
|
free(vcp->vc_mackey, M_SMBTEMP);
|
|
vcp->vc_mackey = NULL;
|
|
vcp->vc_mackeylen = 0;
|
|
vcp->vc_seqno = 0;
|
|
}
|
|
|
|
/*
|
|
* The partial MAC key is the concatenation of the 16 byte session
|
|
* key and the 24 byte challenge response.
|
|
*/
|
|
vcp->vc_mackeylen = 16 + 24;
|
|
vcp->vc_mackey = malloc(vcp->vc_mackeylen, M_SMBTEMP, M_WAITOK);
|
|
|
|
/*
|
|
* Calculate session key:
|
|
* MD4(MD4(U(PN)))
|
|
*/
|
|
pwd = smb_vc_getpass(vcp);
|
|
len = strlen(pwd);
|
|
unipwd = malloc((len + 1) * sizeof(u_int16_t), M_SMBTEMP, M_WAITOK);
|
|
smb_strtouni(unipwd, pwd);
|
|
MD4Init(&md4);
|
|
MD4Update(&md4, (u_char *)unipwd, len * sizeof(u_int16_t));
|
|
MD4Final(S16, &md4);
|
|
MD4Init(&md4);
|
|
MD4Update(&md4, S16, 16);
|
|
MD4Final(vcp->vc_mackey, &md4);
|
|
free(unipwd, M_SMBTEMP);
|
|
|
|
/*
|
|
* Calculate response to challenge:
|
|
* Ex(concat(MD4(U(pass)), zeros(5)), C8)
|
|
*/
|
|
bzero(S21, 21);
|
|
bcopy(S16, S21, 16);
|
|
smb_E(S21, vcp->vc_ch, vcp->vc_mackey + 16);
|
|
smb_E(S21 + 7, vcp->vc_ch, vcp->vc_mackey + 24);
|
|
smb_E(S21 + 14, vcp->vc_ch, vcp->vc_mackey + 32);
|
|
|
|
return (0);
|
|
#else
|
|
panic("smb_calcmackey: encryption not available");
|
|
return (0);
|
|
#endif /* NETSMBCRYPTO */
|
|
}
|
|
|
|
/*
|
|
* Sign request with MAC.
|
|
*/
|
|
int
|
|
smb_rq_sign(struct smb_rq *rqp)
|
|
{
|
|
#ifdef NETSMBCRYPTO
|
|
struct smb_vc *vcp = rqp->sr_vc;
|
|
struct mbchain *mbp;
|
|
struct mbuf *mb;
|
|
MD5_CTX md5;
|
|
u_char digest[16];
|
|
|
|
KASSERT(vcp->vc_hflags2 & SMB_FLAGS2_SECURITY_SIGNATURE,
|
|
("signatures not enabled"));
|
|
|
|
if (vcp->vc_mackey == NULL)
|
|
/* XXX Should assert that cmd == SMB_COM_NEGOTIATE. */
|
|
return (0);
|
|
|
|
/*
|
|
* This is a bit of a kludge. If the request is non-TRANSACTION,
|
|
* or it is the first request of a transaction, give it the next
|
|
* sequence number, and expect the reply to have the sequence number
|
|
* following that one. Otherwise, it is a secondary request in
|
|
* a transaction, and it gets the same sequence numbers as the
|
|
* primary request.
|
|
*/
|
|
if (rqp->sr_t2 == NULL ||
|
|
(rqp->sr_t2->t2_flags & SMBT2_SECONDARY) == 0) {
|
|
rqp->sr_seqno = vcp->vc_seqno++;
|
|
rqp->sr_rseqno = vcp->vc_seqno++;
|
|
} else {
|
|
/*
|
|
* Sequence numbers are already in the struct because
|
|
* smb_t2_request_int() uses the same one for all the
|
|
* requests in the transaction.
|
|
* (At least we hope so.)
|
|
*/
|
|
KASSERT(rqp->sr_t2 == NULL ||
|
|
(rqp->sr_t2->t2_flags & SMBT2_SECONDARY) == 0 ||
|
|
rqp->sr_t2->t2_rq == rqp,
|
|
("sec t2 rq not using same smb_rq"));
|
|
}
|
|
|
|
/* Initialize sec. signature field to sequence number + zeros. */
|
|
*(u_int32_t *)rqp->sr_rqsig = htole32(rqp->sr_seqno);
|
|
*(u_int32_t *)(rqp->sr_rqsig + 4) = 0;
|
|
|
|
/*
|
|
* Compute HMAC-MD5 of packet data, keyed by MAC key.
|
|
* Store the first 8 bytes in the sec. signature field.
|
|
*/
|
|
smb_rq_getrequest(rqp, &mbp);
|
|
MD5Init(&md5);
|
|
MD5Update(&md5, vcp->vc_mackey, vcp->vc_mackeylen);
|
|
for (mb = mbp->mb_top; mb != NULL; mb = mb->m_next)
|
|
MD5Update(&md5, mtod(mb, void *), mb->m_len);
|
|
MD5Final(digest, &md5);
|
|
bcopy(digest, rqp->sr_rqsig, 8);
|
|
|
|
return (0);
|
|
#else
|
|
panic("smb_rq_sign: encryption not available");
|
|
return (0);
|
|
#endif /* NETSMBCRYPTO */
|
|
}
|
|
|
|
/*
|
|
* Verify reply signature.
|
|
*/
|
|
int
|
|
smb_rq_verify(struct smb_rq *rqp)
|
|
{
|
|
#ifdef NETSMBCRYPTO
|
|
struct smb_vc *vcp = rqp->sr_vc;
|
|
struct mdchain *mdp;
|
|
u_char sigbuf[8];
|
|
MD5_CTX md5;
|
|
u_char digest[16];
|
|
struct mbuf *mb;
|
|
|
|
KASSERT(vcp->vc_hflags2 & SMB_FLAGS2_SECURITY_SIGNATURE,
|
|
("signatures not enabled"));
|
|
|
|
if (vcp->vc_mackey == NULL)
|
|
/* XXX Should check that this is a SMB_COM_NEGOTIATE reply. */
|
|
return (0);
|
|
|
|
/*
|
|
* Compute HMAC-MD5 of packet data, keyed by MAC key.
|
|
* We play games to pretend the security signature field
|
|
* contains their sequence number, to avoid modifying
|
|
* the packet itself.
|
|
*/
|
|
smb_rq_getreply(rqp, &mdp);
|
|
mb = mdp->md_top;
|
|
KASSERT(mb->m_len >= SMB_HDRLEN, ("forgot to m_pullup"));
|
|
MD5Init(&md5);
|
|
MD5Update(&md5, vcp->vc_mackey, vcp->vc_mackeylen);
|
|
MD5Update(&md5, mtod(mb, void *), 14);
|
|
*(u_int32_t *)sigbuf = htole32(rqp->sr_rseqno);
|
|
*(u_int32_t *)(sigbuf + 4) = 0;
|
|
MD5Update(&md5, sigbuf, 8);
|
|
MD5Update(&md5, mtod(mb, u_char *) + 22, mb->m_len - 22);
|
|
for (mb = mb->m_next; mb != NULL; mb = mb->m_next)
|
|
MD5Update(&md5, mtod(mb, void *), mb->m_len);
|
|
MD5Final(digest, &md5);
|
|
|
|
/*
|
|
* Now verify the signature.
|
|
*/
|
|
if (bcmp(mtod(mdp->md_top, u_char *) + 14, digest, 8) != 0)
|
|
return (EAUTH);
|
|
|
|
return (0);
|
|
#else
|
|
panic("smb_rq_verify: encryption not available");
|
|
return (0);
|
|
#endif /* NETSMBCRYPTO */
|
|
}
|