From 1fa7300037447c6e01438509343afd2e186f066c Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 24 Oct 2011 16:50:19 +0200 Subject: libcli/smb: move smb_signing.[ch] to the toplevel metze --- source3/libsmb/smb_signing.c | 453 ------------------------------------------- 1 file changed, 453 deletions(-) delete mode 100644 source3/libsmb/smb_signing.c (limited to 'source3/libsmb/smb_signing.c') diff --git a/source3/libsmb/smb_signing.c b/source3/libsmb/smb_signing.c deleted file mode 100644 index 1f9d36889a..0000000000 --- a/source3/libsmb/smb_signing.c +++ /dev/null @@ -1,453 +0,0 @@ -/* - Unix SMB/CIFS implementation. - SMB Signing Code - Copyright (C) Jeremy Allison 2003. - Copyright (C) Andrew Bartlett 2002-2003 - Copyright (C) Stefan Metzmacher 2009 - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 3 of the License, or - (at your option) any later version. - - This program 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 General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program. If not, see . -*/ - -#include "includes.h" -#include "../lib/crypto/md5.h" -#include "smb_signing.h" - -/* Used by the SMB signing functions. */ - -struct smb_signing_state { - /* is signing localy allowed */ - bool allowed; - - /* is signing localy desired */ - bool desired; - - /* is signing localy mandatory */ - bool mandatory; - - /* is signing negotiated by the peer */ - bool negotiated; - - bool active; /* Have I ever seen a validly signed packet? */ - - /* mac_key.length > 0 means signing is started */ - DATA_BLOB mac_key; - - /* the next expected seqnum */ - uint32_t seqnum; - - TALLOC_CTX *mem_ctx; - void *(*alloc_fn)(TALLOC_CTX *mem_ctx, size_t len); - void (*free_fn)(TALLOC_CTX *mem_ctx, void *ptr); -}; - -static void smb_signing_reset_info(struct smb_signing_state *si) -{ - si->active = false; - si->seqnum = 0; - - if (si->free_fn) { - si->free_fn(si->mem_ctx, si->mac_key.data); - } else { - talloc_free(si->mac_key.data); - } - si->mac_key.data = NULL; - si->mac_key.length = 0; -} - -struct smb_signing_state *smb_signing_init_ex(TALLOC_CTX *mem_ctx, - bool allowed, - bool desired, - bool mandatory, - void *(*alloc_fn)(TALLOC_CTX *, size_t), - void (*free_fn)(TALLOC_CTX *, void *)) -{ - struct smb_signing_state *si; - - if (alloc_fn) { - void *p = alloc_fn(mem_ctx, sizeof(struct smb_signing_state)); - if (p == NULL) { - return NULL; - } - memset(p, 0, sizeof(struct smb_signing_state)); - si = (struct smb_signing_state *)p; - si->mem_ctx = mem_ctx; - si->alloc_fn = alloc_fn; - si->free_fn = free_fn; - } else { - si = talloc_zero(mem_ctx, struct smb_signing_state); - if (si == NULL) { - return NULL; - } - } - - if (mandatory) { - desired = true; - } - - if (desired) { - allowed = true; - } - - si->allowed = allowed; - si->desired = desired; - si->mandatory = mandatory; - - return si; -} - -struct smb_signing_state *smb_signing_init(TALLOC_CTX *mem_ctx, - bool allowed, - bool desired, - bool mandatory) -{ - return smb_signing_init_ex(mem_ctx, allowed, desired, mandatory, - NULL, NULL); -} - -static bool smb_signing_good(struct smb_signing_state *si, - bool good, uint32_t seq) -{ - if (good) { - if (!si->active) { - si->active = true; - } - return true; - } - - if (!si->mandatory && !si->active) { - /* Non-mandatory signing - just turn off if this is the first bad packet.. */ - DEBUG(5, ("smb_signing_good: signing negotiated but not required and peer\n" - "isn't sending correct signatures. Turning off.\n")); - smb_signing_reset_info(si); - return true; - } - - /* Mandatory signing or bad packet after signing started - fail and disconnect. */ - DEBUG(0, ("smb_signing_good: BAD SIG: seq %u\n", (unsigned int)seq)); - return false; -} - -static void smb_signing_md5(const DATA_BLOB *mac_key, - const uint8_t *buf, uint32_t seq_number, - uint8_t calc_md5_mac[16]) -{ - const size_t offset_end_of_sig = (NBT_HDR_SIZE + HDR_SS_FIELD + 8); - uint8_t sequence_buf[8]; - struct MD5Context md5_ctx; - - /* - * Firstly put the sequence number into the first 4 bytes. - * and zero out the next 4 bytes. - * - * We do this here, to avoid modifying the packet. - */ - - DEBUG(10,("smb_signing_md5: sequence number %u\n", seq_number )); - - SIVAL(sequence_buf, 0, seq_number); - SIVAL(sequence_buf, 4, 0); - - /* Calculate the 16 byte MAC - but don't alter the data in the - incoming packet. - - This makes for a bit of fussing about, but it's not too bad. - */ - MD5Init(&md5_ctx); - - /* intialise with the key */ - MD5Update(&md5_ctx, mac_key->data, mac_key->length); - - /* copy in the first bit of the SMB header */ - MD5Update(&md5_ctx, buf + NBT_HDR_SIZE, HDR_SS_FIELD); - - /* copy in the sequence number, instead of the signature */ - MD5Update(&md5_ctx, sequence_buf, sizeof(sequence_buf)); - - /* copy in the rest of the packet in, skipping the signature */ - MD5Update(&md5_ctx, buf + offset_end_of_sig, - smb_len_nbt(buf) - (offset_end_of_sig - 4)); - - /* calculate the MD5 sig */ - MD5Final(calc_md5_mac, &md5_ctx); -} - -uint32_t smb_signing_next_seqnum(struct smb_signing_state *si, bool oneway) -{ - uint32_t seqnum; - - if (si->mac_key.length == 0) { - return 0; - } - - seqnum = si->seqnum; - if (oneway) { - si->seqnum += 1; - } else { - si->seqnum += 2; - } - - return seqnum; -} - -void smb_signing_cancel_reply(struct smb_signing_state *si, bool oneway) -{ - if (si->mac_key.length == 0) { - return; - } - - if (oneway) { - si->seqnum -= 1; - } else { - si->seqnum -= 2; - } -} - -void smb_signing_sign_pdu(struct smb_signing_state *si, - uint8_t *outbuf, uint32_t seqnum) -{ - uint8_t calc_md5_mac[16]; - uint8_t com; - uint8_t flags; - - if (si->mac_key.length == 0) { - if (!si->negotiated) { - return; - } - } - - /* JRA Paranioa test - we should be able to get rid of this... */ - if (smb_len_nbt(outbuf) < (HDR_SS_FIELD + 8)) { - DEBUG(1,("smb_signing_sign_pdu: Logic error. " - "Can't check signature on short packet! smb_len = %u\n", - smb_len_nbt(outbuf))); - abort(); - } - - com = SVAL(outbuf,NBT_HDR_SIZE+HDR_COM); - flags = SVAL(outbuf,NBT_HDR_SIZE+HDR_FLG); - - if (!(flags & FLAG_REPLY)) { - uint16_t flags2 = SVAL(outbuf,NBT_HDR_SIZE+HDR_FLG2); - /* - * If this is a request, specify what is - * supported or required by the client - */ - if (si->negotiated && si->desired) { - flags2 |= FLAGS2_SMB_SECURITY_SIGNATURES; - } - if (si->negotiated && si->mandatory) { - flags2 |= FLAGS2_SMB_SECURITY_SIGNATURES_REQUIRED; - } - SSVAL(outbuf, NBT_HDR_SIZE+HDR_FLG2, flags2); - } - - if (si->mac_key.length == 0) { - /* I wonder what BSRSPYL stands for - but this is what MS - actually sends! */ - if (com == SMBsesssetupX) { - memcpy(calc_md5_mac, "BSRSPYL ", 8); - } else { - memset(calc_md5_mac, 0, 8); - } - } else { - smb_signing_md5(&si->mac_key, outbuf, - seqnum, calc_md5_mac); - } - - DEBUG(10, ("smb_signing_sign_pdu: sent SMB signature of\n")); - dump_data(10, calc_md5_mac, 8); - - memcpy(&outbuf[NBT_HDR_SIZE+HDR_SS_FIELD], calc_md5_mac, 8); - -/* outbuf[NBT_HDR_SIZE+HDR_SS_FIELD+2]=0; - Uncomment this to test if the remote server actually verifies signatures...*/ -} - -bool smb_signing_check_pdu(struct smb_signing_state *si, - const uint8_t *inbuf, uint32_t seqnum) -{ - bool good; - uint8_t calc_md5_mac[16]; - const uint8_t *reply_sent_mac; - - if (si->mac_key.length == 0) { - return true; - } - - if (smb_len_nbt(inbuf) < (HDR_SS_FIELD + 8)) { - DEBUG(1,("smb_signing_check_pdu: Can't check signature " - "on short packet! smb_len = %u\n", - smb_len_nbt(inbuf))); - return false; - } - - smb_signing_md5(&si->mac_key, inbuf, - seqnum, calc_md5_mac); - - reply_sent_mac = &inbuf[NBT_HDR_SIZE+HDR_SS_FIELD]; - good = (memcmp(reply_sent_mac, calc_md5_mac, 8) == 0); - - if (!good) { - int i; - const int sign_range = 5; - - DEBUG(5, ("smb_signing_check_pdu: BAD SIG: wanted SMB signature of\n")); - dump_data(5, calc_md5_mac, 8); - - DEBUG(5, ("smb_signing_check_pdu: BAD SIG: got SMB signature of\n")); - dump_data(5, reply_sent_mac, 8); - - for (i = -sign_range; i < sign_range; i++) { - smb_signing_md5(&si->mac_key, inbuf, - seqnum+i, calc_md5_mac); - if (memcmp(reply_sent_mac, calc_md5_mac, 8) == 0) { - DEBUG(0,("smb_signing_check_pdu: " - "out of seq. seq num %u matches. " - "We were expecting seq %u\n", - (unsigned int)seqnum+i, - (unsigned int)seqnum)); - break; - } - } - } else { - DEBUG(10, ("smb_signing_check_pdu: seq %u: " - "got good SMB signature of\n", - (unsigned int)seqnum)); - dump_data(10, reply_sent_mac, 8); - } - - return smb_signing_good(si, good, seqnum); -} - -bool smb_signing_activate(struct smb_signing_state *si, - const DATA_BLOB user_session_key, - const DATA_BLOB response) -{ - size_t len; - off_t ofs; - - if (!user_session_key.length) { - return false; - } - - if (!si->negotiated) { - return false; - } - - if (si->active) { - return false; - } - - if (si->mac_key.length > 0) { - return false; - } - - smb_signing_reset_info(si); - - len = response.length + user_session_key.length; - if (si->alloc_fn) { - si->mac_key.data = (uint8_t *)si->alloc_fn(si->mem_ctx, len); - if (si->mac_key.data == NULL) { - return false; - } - } else { - si->mac_key.data = (uint8_t *)talloc_size(si, len); - if (si->mac_key.data == NULL) { - return false; - } - } - si->mac_key.length = len; - - ofs = 0; - memcpy(&si->mac_key.data[ofs], user_session_key.data, user_session_key.length); - - DEBUG(10, ("smb_signing_activate: user_session_key\n")); - dump_data(10, user_session_key.data, user_session_key.length); - - if (response.length) { - ofs = user_session_key.length; - memcpy(&si->mac_key.data[ofs], response.data, response.length); - DEBUG(10, ("smb_signing_activate: response_data\n")); - dump_data(10, response.data, response.length); - } else { - DEBUG(10, ("smb_signing_activate: NULL response_data\n")); - } - - dump_data_pw("smb_signing_activate: mac key is:\n", - si->mac_key.data, si->mac_key.length); - - /* Initialise the sequence number */ - si->seqnum = 2; - - return true; -} - -bool smb_signing_is_active(struct smb_signing_state *si) -{ - return si->active; -} - -bool smb_signing_is_allowed(struct smb_signing_state *si) -{ - return si->allowed; -} - -bool smb_signing_is_mandatory(struct smb_signing_state *si) -{ - return si->mandatory; -} - -bool smb_signing_set_negotiated(struct smb_signing_state *si, - bool allowed, bool mandatory) -{ - if (si->active) { - return true; - } - - if (!si->allowed && mandatory) { - return false; - } - - if (si->mandatory && !allowed) { - return false; - } - - if (si->mandatory) { - si->negotiated = true; - return true; - } - - if (mandatory) { - si->negotiated = true; - return true; - } - - if (!si->desired) { - si->negotiated = false; - return true; - } - - if (si->desired && allowed) { - si->negotiated = true; - return true; - } - - si->negotiated = false; - return true; -} - -bool smb_signing_is_negotiated(struct smb_signing_state *si) -{ - return si->negotiated; -} -- cgit