/* Unix SMB/CIFS implementation. handle unexpected packets Copyright (C) Andrew Tridgell 2000 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 <http://www.gnu.org/licenses/>. */ #include "includes.h" static struct tdb_wrap *tdbd = NULL; /* the key type used in the unexpected packet database */ struct unexpected_key { enum packet_type packet_type; time_t timestamp; int count; }; /**************************************************************************** All unexpected packets are passed in here, to be stored in a unexpected packet database. This allows nmblookup and other tools to receive packets erroneously sent to the wrong port by broken MS systems. **************************************************************************/ void unexpected_packet(struct packet_struct *p) { static int count; TDB_DATA kbuf, dbuf; struct unexpected_key key; char buf[1024]; int len=0; uint32_t enc_ip; if (!tdbd) { tdbd = tdb_wrap_open(talloc_autofree_context(), lock_path("unexpected.tdb"), 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT, O_RDWR | O_CREAT, 0644); if (!tdbd) { DEBUG(0,("Failed to open unexpected.tdb\n")); return; } } memset(buf,'\0',sizeof(buf)); /* Encode the ip addr and port. */ enc_ip = ntohl(p->ip.s_addr); SIVAL(buf,0,enc_ip); SSVAL(buf,4,p->port); len = build_packet(&buf[6], sizeof(buf)-6, p) + 6; ZERO_STRUCT(key); /* needed for potential alignment */ key.packet_type = p->packet_type; key.timestamp = p->timestamp; key.count = count++; kbuf.dptr = (uint8_t *)&key; kbuf.dsize = sizeof(key); dbuf.dptr = (uint8_t *)buf; dbuf.dsize = len; tdb_store(tdbd->tdb, kbuf, dbuf, TDB_REPLACE); } static time_t lastt; /**************************************************************************** Delete the record if it is too old. **************************************************************************/ static int traverse_fn(TDB_CONTEXT *ttdb, TDB_DATA kbuf, TDB_DATA dbuf, void *state) { struct unexpected_key key; if (kbuf.dsize != sizeof(key)) { tdb_delete(ttdb, kbuf); } memcpy(&key, kbuf.dptr, sizeof(key)); if (lastt - key.timestamp > NMBD_UNEXPECTED_TIMEOUT) { tdb_delete(ttdb, kbuf); } return 0; } /**************************************************************************** Delete all old unexpected packets. **************************************************************************/ void clear_unexpected(time_t t) { if (!tdbd) return; if ((lastt != 0) && (t < lastt + NMBD_UNEXPECTED_TIMEOUT)) return; lastt = t; tdb_traverse(tdbd->tdb, traverse_fn, NULL); } struct receive_unexpected_state { struct packet_struct *matched_packet; int match_id; enum packet_type match_type; const char *match_name; }; /**************************************************************************** tdb traversal fn to find a matching 137 packet. **************************************************************************/ static int traverse_match(TDB_CONTEXT *ttdb, TDB_DATA kbuf, TDB_DATA dbuf, void *private_data) { struct receive_unexpected_state *state = (struct receive_unexpected_state *)private_data; struct unexpected_key key; struct in_addr ip; uint32_t enc_ip; int port; struct packet_struct *p; if (kbuf.dsize != sizeof(key)) { return 0; } memcpy(&key, kbuf.dptr, sizeof(key)); if (key.packet_type != state->match_type) return 0; if (dbuf.dsize < 6) { return 0; } /* Decode the ip addr and port. */ enc_ip = IVAL(dbuf.dptr,0); ip.s_addr = htonl(enc_ip); port = SVAL(dbuf.dptr,4); p = parse_packet((char *)&dbuf.dptr[6], dbuf.dsize-6, state->match_type, ip, port); if (!p) return 0; if ((state->match_type == NMB_PACKET && p->packet.nmb.header.name_trn_id == state->match_id) || (state->match_type == DGRAM_PACKET && match_mailslot_name(p, state->match_name))) { state->matched_packet = p; return -1; } free_packet(p); return 0; } /**************************************************************************** Check for a particular packet in the unexpected packet queue. **************************************************************************/ struct packet_struct *receive_unexpected(enum packet_type packet_type, int id, const char *mailslot_name) { struct tdb_wrap *tdb2; struct receive_unexpected_state state; tdb2 = tdb_wrap_open(talloc_autofree_context(), lock_path("unexpected.tdb"), 0, 0, O_RDONLY, 0); if (!tdb2) return NULL; state.matched_packet = NULL; state.match_id = id; state.match_type = packet_type; state.match_name = mailslot_name; tdb_traverse(tdb2->tdb, traverse_match, &state); TALLOC_FREE(tdb2); return state.matched_packet; }