/*- * 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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); }