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Diffstat (limited to 'source4/libcli/dgram/mailslot.c')
| -rw-r--r-- | source4/libcli/dgram/mailslot.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/source4/libcli/dgram/mailslot.c b/source4/libcli/dgram/mailslot.c new file mode 100644 index 0000000..a24800c --- /dev/null +++ b/source4/libcli/dgram/mailslot.c @@ -0,0 +1,229 @@ +/* + Unix SMB/CIFS implementation. + + packet handling for mailslot requests. + + Copyright (C) Andrew Tridgell 2005 + + 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/>. +*/ + +/* + This implements "Class 2 mailslots", i.e. the communication mechanism + used for all mailslot packets smaller than 425 bytes. + + "Class 1 mailslots" (which use SMB) are used for messages larger + than 426 bytes and are supported on some systems. These are not implemented + in Samba4 yet, as there don't appear to be any core services that use + them. + + 425 and 426-byte sized messages are not supported at all. +*/ + +#include "includes.h" +#include "lib/events/events.h" +#include "../lib/util/dlinklist.h" +#include "libcli/dgram/libdgram.h" +#include "lib/socket/socket.h" + +#undef strcasecmp + +/* + destroy a mailslot handler +*/ +static int dgram_mailslot_destructor(struct dgram_mailslot_handler *dgmslot) +{ + DLIST_REMOVE(dgmslot->dgmsock->mailslot_handlers, dgmslot); + return 0; +} + +/* + start listening on a mailslot. talloc_free() the handle to stop listening +*/ +struct dgram_mailslot_handler *dgram_mailslot_listen(struct nbt_dgram_socket *dgmsock, + const char *mailslot_name, + dgram_mailslot_handler_t handler, + void *private_data) +{ + struct dgram_mailslot_handler *dgmslot; + + dgmslot = talloc(dgmsock, struct dgram_mailslot_handler); + if (dgmslot == NULL) return NULL; + + dgmslot->dgmsock = dgmsock; + dgmslot->mailslot_name = talloc_strdup(dgmslot, mailslot_name); + if (dgmslot->mailslot_name == NULL) { + talloc_free(dgmslot); + return NULL; + } + dgmslot->handler = handler; + dgmslot->private_data = private_data; + + DLIST_ADD(dgmsock->mailslot_handlers, dgmslot); + talloc_set_destructor(dgmslot, dgram_mailslot_destructor); + + TEVENT_FD_READABLE(dgmsock->fde); + + return dgmslot; +} + +/* + find the handler for a specific mailslot name +*/ +struct dgram_mailslot_handler *dgram_mailslot_find(struct nbt_dgram_socket *dgmsock, + const char *mailslot_name) +{ + struct dgram_mailslot_handler *h; + for (h=dgmsock->mailslot_handlers;h;h=h->next) { + if (strcasecmp(h->mailslot_name, mailslot_name) == 0) { + return h; + } + } + return NULL; +} + +/* + check that a datagram packet is a valid mailslot request, and return the + mailslot name if it is, otherwise return NULL +*/ +const char *dgram_mailslot_name(struct nbt_dgram_packet *packet) +{ + if (packet->msg_type != DGRAM_DIRECT_UNIQUE && + packet->msg_type != DGRAM_DIRECT_GROUP && + packet->msg_type != DGRAM_BCAST) { + return NULL; + } + if (packet->data.msg.dgram_body_type != DGRAM_SMB) return NULL; + if (packet->data.msg.body.smb.smb_command != SMB_TRANSACTION) return NULL; + return packet->data.msg.body.smb.body.trans.mailslot_name; +} + + +/* + create a temporary mailslot handler for a reply mailslot, allocating + a new mailslot name using the given base name and a random integer extension +*/ +struct dgram_mailslot_handler *dgram_mailslot_temp(struct nbt_dgram_socket *dgmsock, + const char *mailslot_name, + dgram_mailslot_handler_t handler, + void *private_data) +{ + char *name; + int i; + struct dgram_mailslot_handler *dgmslot; + + /* try a 100 times at most */ + for (i=0;i<100;i++) { + name = talloc_asprintf(dgmsock, "%s%03u", + mailslot_name, + generate_random() % 1000); + if (name == NULL) return NULL; + if (dgram_mailslot_find(dgmsock, name)) { + talloc_free(name); + continue; + } + dgmslot = dgram_mailslot_listen(dgmsock, name, handler, private_data); + talloc_free(name); + if (dgmslot != NULL) { + return dgmslot; + } + } + DEBUG(2,("Unable to create temporary mailslot from %s\n", mailslot_name)); + return NULL; +} + + +/* + send a mailslot request +*/ +NTSTATUS dgram_mailslot_send(struct nbt_dgram_socket *dgmsock, + enum dgram_msg_type msg_type, + const char *mailslot_name, + struct nbt_name *dest_name, + struct socket_address *dest, + struct nbt_name *src_name, + DATA_BLOB *request) +{ + TALLOC_CTX *tmp_ctx = talloc_new(dgmsock); + struct nbt_dgram_packet packet; + struct dgram_message *msg; + struct dgram_smb_packet *smb; + struct smb_trans_body *trans; + struct socket_address *src; + NTSTATUS status; + + if (dest->port == 0) { + return NT_STATUS_INVALID_PARAMETER; + } + + ZERO_STRUCT(packet); + packet.msg_type = msg_type; + packet.flags = DGRAM_FLAG_FIRST | DGRAM_NODE_NBDD; + packet.dgram_id = generate_random() % UINT16_MAX; + src = socket_get_my_addr(dgmsock->sock, tmp_ctx); + if (!src) { + talloc_free(tmp_ctx); + return NT_STATUS_NO_MEMORY; + } + packet.src_addr = src->addr; + packet.src_port = src->port; + + msg = &packet.data.msg; + /* this length calculation is very crude - it should be based on gensize + calls */ + msg->length = 138 + strlen(mailslot_name) + request->length; + msg->offset = 0; + + msg->source_name = *src_name; + msg->dest_name = *dest_name; + msg->dgram_body_type = DGRAM_SMB; + + smb = &msg->body.smb; + smb->smb_command = SMB_TRANSACTION; + + trans = &smb->body.trans; + trans->total_data_count = request->length; + trans->timeout = 1000; + trans->data_count = request->length; + trans->data_offset = 70 + strlen(mailslot_name); + trans->opcode = 1; /* write mail slot */ + trans->priority = 1; + trans->_class = 2; + trans->mailslot_name = mailslot_name; + trans->data = *request; + + status = nbt_dgram_send(dgmsock, &packet, dest); + + talloc_free(tmp_ctx); + + return status; +} + +/* + return the mailslot data portion from a mailslot packet +*/ +DATA_BLOB dgram_mailslot_data(struct nbt_dgram_packet *dgram) +{ + struct smb_trans_body *trans = &dgram->data.msg.body.smb.body.trans; + DATA_BLOB ret = trans->data; + int pad = trans->data_offset - (70 + strlen(trans->mailslot_name)); + + if (pad < 0 || pad > ret.length) { + DEBUG(2,("Badly formatted data in mailslot - pad = %d\n", pad)); + return data_blob(NULL, 0); + } + ret.data += pad; + ret.length -= pad; + return ret; +} |