/src/freebsd/sys/netsmb/smb_crypt.c
C | 309 lines | 182 code | 36 blank | 91 comment | 19 complexity | 8701a59e8fb5eae9857f838b044bc907 MD5 | raw file
Possible License(s): CC0-1.0, MIT, LGPL-2.0, LGPL-3.0, WTFPL, GPL-2.0, BSD-2-Clause, AGPL-3.0, CC-BY-SA-3.0, MPL-2.0, JSON, BSD-3-Clause-No-Nuclear-License-2014, LGPL-2.1, CPL-1.0, AGPL-1.0, 0BSD, ISC, Apache-2.0, GPL-3.0, IPL-1.0, MPL-2.0-no-copyleft-exception, BSD-3-Clause
- /*-
- * 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 <crypto/des/des.h>
- #include "opt_netsmb.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);
- }
- int
- smb_encrypt(const u_char *apwd, u_char *C8, u_char *RN)
- {
- 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;
- }
- int
- smb_ntencrypt(const u_char *apwd, u_char *C8, u_char *RN)
- {
- 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;
- }
- /*
- * Calculate message authentication code (MAC) key for virtual circuit.
- */
- int
- smb_calcmackey(struct smb_vc *vcp)
- {
- 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);
- }
- /*
- * Sign request with MAC.
- */
- int
- smb_rq_sign(struct smb_rq *rqp)
- {
- 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. */
- le32enc(rqp->sr_rqsig, rqp->sr_seqno);
- le32enc(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);
- }
- /*
- * Verify reply signature.
- */
- int
- smb_rq_verify(struct smb_rq *rqp)
- {
- 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);
- }