diff options
| -rw-r--r-- | source4/lib/stream/config.mk | 9 | ||||
| -rw-r--r-- | source4/lib/stream/packet.c | 312 | ||||
| -rw-r--r-- | source4/lib/stream/packet.h | 47 |
3 files changed, 368 insertions, 0 deletions
diff --git a/source4/lib/stream/config.mk b/source4/lib/stream/config.mk new file mode 100644 index 0000000000..1ec650ab10 --- /dev/null +++ b/source4/lib/stream/config.mk @@ -0,0 +1,9 @@ + +################################################ +# Start SUBSYSTEM LIBPACKET +[SUBSYSTEM::LIBPACKET] +INIT_OBJ_FILES = \ + packet.o +NOPROTO=YES +# End SUBSYSTEM LIBPACKET +################################################ diff --git a/source4/lib/stream/packet.c b/source4/lib/stream/packet.c new file mode 100644 index 0000000000..971135ff9b --- /dev/null +++ b/source4/lib/stream/packet.c @@ -0,0 +1,312 @@ +/* + Unix SMB/CIFS mplementation. + + helper layer for breaking up streams into discrete 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 2 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, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ + +#include "includes.h" +#include "dlinklist.h" +#include "lib/events/events.h" +#include "lib/socket/socket.h" +#include "lib/tls/tls.h" +#include "lib/stream/packet.h" + + +struct packet_context { + packet_callback_fn_t callback; + packet_full_request_fn_t full_request; + packet_error_handler_fn_t error_handler; + DATA_BLOB partial; + uint32_t initial_read_size; + uint32_t num_read; + struct tls_context *tls; + struct socket_context *sock; + struct event_context *ev; + size_t packet_size; + void *private; +}; + +/* + initialise a packet receiver +*/ +struct packet_context *packet_init(TALLOC_CTX *mem_ctx) +{ + return talloc_zero(mem_ctx, struct packet_context); +} + + +/* + set the request callback, called when a full request is ready +*/ +void packet_set_callback(struct packet_context *pc, packet_callback_fn_t callback) +{ + pc->callback = callback; +} + +/* + set the error handler +*/ +void packet_set_error_handler(struct packet_context *pc, packet_error_handler_fn_t handler) +{ + pc->error_handler = handler; +} + +/* + set the private pointer passed to the callback functions +*/ +void packet_set_private(struct packet_context *pc, void *private) +{ + pc->private = private; +} + +/* + set the full request callback. Should return as follows: + NT_STATUS_OK == blob is a full request. + STATUS_MORE_ENTRIES == blob is not complete yet + any error == blob is not a valid +*/ +void packet_set_full_request(struct packet_context *pc, packet_full_request_fn_t callback) +{ + pc->full_request = callback; +} + +/* + set a tls context to use. You must either set a tls_context or a socket_context +*/ +void packet_set_tls(struct packet_context *pc, struct tls_context *tls) +{ + pc->tls = tls; +} + +/* + set a socket context to use. You must either set a tls_context or a socket_context +*/ +void packet_set_socket(struct packet_context *pc, struct socket_context *sock) +{ + pc->sock = sock; +} + +/* + set an event context. If this is set then the code will ensure that + packets arrive with separate events, by creating a immediate event + for any secondary packets when more than one packet is read at one + time on a socket. This can matter for code that relies on not + getting more than one packet per event +*/ +void packet_set_event_context(struct packet_context *pc, struct event_context *ev) +{ + pc->ev = ev; +} + + +/* + tell the caller we have an error +*/ +static void packet_error(struct packet_context *pc, NTSTATUS status) +{ + pc->tls = NULL; + pc->sock = NULL; + if (pc->error_handler) { + pc->error_handler(pc->private, status); + return; + } + /* default error handler is to free the callers private pointer */ + if (!NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) { + DEBUG(0,("packet_error on %s - %s\n", + talloc_get_name(pc->private), nt_errstr(status))); + } + talloc_free(pc->private); + return; +} + + +/* + tell the caller we have EOF +*/ +static void packet_eof(struct packet_context *pc) +{ + packet_error(pc, NT_STATUS_END_OF_FILE); +} + + +/* + used to put packets on event boundaries +*/ +static void packet_next_event(struct event_context *ev, struct timed_event *te, + struct timeval t, void *private) +{ + struct packet_context *pc = talloc_get_type(private, struct packet_context); + packet_recv(pc); +} + +/* + call this when the socket becomes readable to kick off the whole + stream parsing process +*/ +void packet_recv(struct packet_context *pc) +{ + size_t npending; + NTSTATUS status; + size_t nread; + DATA_BLOB blob; + + if (pc->packet_size != 0 && pc->num_read >= pc->packet_size) { + goto next_partial; + } + + if (pc->packet_size != 0) { + /* we've already worked out how long this next packet is, so skip the + socket_pending() call */ + npending = pc->packet_size - pc->num_read; + } else { + if (pc->tls) { + status = tls_socket_pending(pc->tls, &npending); + } else if (pc->sock) { + status = socket_pending(pc->sock, &npending); + } else { + status = NT_STATUS_CONNECTION_DISCONNECTED; + } + if (!NT_STATUS_IS_OK(status)) { + packet_error(pc, status); + return; + } + } + + if (npending == 0) { + packet_eof(pc); + return; + } + + /* possibly expand the partial packet buffer */ + if (npending + pc->num_read > pc->partial.length) { + status = data_blob_realloc(pc, &pc->partial, npending+pc->num_read); + if (!NT_STATUS_IS_OK(status)) { + packet_error(pc, status); + return; + } + } + + if (pc->tls) { + status = tls_socket_recv(pc->tls, pc->partial.data + pc->num_read, + npending, &nread); + } else { + status = socket_recv(pc->sock, pc->partial.data + pc->num_read, + npending, &nread, 0); + } + if (NT_STATUS_IS_ERR(status)) { + packet_error(pc, status); + return; + } + if (!NT_STATUS_IS_OK(status)) { + return; + } + + if (nread == 0) { + packet_eof(pc); + return; + } + + pc->num_read += nread; + + /* see if its a full request */ +next_partial: + blob = pc->partial; + blob.length = pc->num_read; + status = pc->full_request(pc->private, blob, &pc->packet_size); + if (NT_STATUS_IS_ERR(status)) { + packet_error(pc, status); + return; + } + if (!NT_STATUS_IS_OK(status)) { + return; + } + + if (pc->packet_size > pc->num_read) { + /* the caller made an error */ + DEBUG(0,("Invalid packet_size %u greater than num_read %u\n", + pc->packet_size, pc->num_read)); + packet_error(pc, NT_STATUS_INVALID_PARAMETER); + return; + } + + /* it is a full request - give it to the caller */ + blob = pc->partial; + + if (pc->packet_size < pc->num_read) { + pc->partial = data_blob_talloc(pc, blob.data + pc->packet_size, + pc->num_read - pc->packet_size); + if (pc->partial.data == NULL) { + packet_error(pc, NT_STATUS_NO_MEMORY); + return; + } + data_blob_realloc(pc, &blob, pc->packet_size); + } else { + pc->partial = data_blob(NULL, 0); + } + pc->num_read -= pc->packet_size; + pc->packet_size = 0; + + status = pc->callback(pc->private, blob); + if (!NT_STATUS_IS_OK(status)) { + packet_error(pc, status); + return; + } + + if (pc->partial.length == 0) { + return; + } + + /* we got multiple packets in one tcp read */ + if (pc->ev == NULL) { + goto next_partial; + } + + blob = pc->partial; + blob.length = pc->num_read; + + status = pc->full_request(pc->private, blob, &pc->packet_size); + if (NT_STATUS_IS_ERR(status)) { + packet_error(pc, status); + return; + } + + if (!NT_STATUS_IS_OK(status)) { + return; + } + + event_add_timed(pc->ev, pc, timeval_zero(), packet_next_event, pc); +} + + + +/* + a full request checker for NBT formatted packets (first 3 bytes are length) +*/ +NTSTATUS packet_full_request_nbt(void *private, DATA_BLOB blob, size_t *packet_size) +{ + if (blob.length < 4) { + return STATUS_MORE_ENTRIES; + } + *packet_size = 4 + smb_len(blob.data); + if (*packet_size > blob.length) { + return STATUS_MORE_ENTRIES; + } + return NT_STATUS_OK; +} diff --git a/source4/lib/stream/packet.h b/source4/lib/stream/packet.h new file mode 100644 index 0000000000..6d29264a28 --- /dev/null +++ b/source4/lib/stream/packet.h @@ -0,0 +1,47 @@ +/* + Unix SMB/CIFS mplementation. + + helper layer for breaking up streams into discrete 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 2 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, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ + +#include "lib/tls/tls.h" + +typedef NTSTATUS (*packet_full_request_fn_t)(void *private, + DATA_BLOB blob, size_t *packet_size); +typedef NTSTATUS (*packet_callback_fn_t)(void *private, DATA_BLOB blob); +typedef void (*packet_error_handler_fn_t)(void *private, NTSTATUS status); + + + +struct packet_context *packet_init(TALLOC_CTX *mem_ctx); +void packet_set_callback(struct packet_context *pc, packet_callback_fn_t callback); +void packet_set_error_handler(struct packet_context *pc, packet_error_handler_fn_t handler); +void packet_set_private(struct packet_context *pc, void *private); +void packet_set_full_request(struct packet_context *pc, packet_full_request_fn_t callback); +void packet_set_tls(struct packet_context *pc, struct tls_context *tls); +void packet_set_socket(struct packet_context *pc, struct socket_context *sock); +void packet_set_event_context(struct packet_context *pc, struct event_context *ev); +void packet_recv(struct packet_context *pc); + +/* + pre-canned handlers +*/ +NTSTATUS packet_full_request_nbt(void *private, DATA_BLOB blob, size_t *packet_size); + |