diff options
Diffstat (limited to 'source3/smbd/scavenger.c')
| -rw-r--r-- | source3/smbd/scavenger.c | 531 |
1 files changed, 531 insertions, 0 deletions
diff --git a/source3/smbd/scavenger.c b/source3/smbd/scavenger.c new file mode 100644 index 0000000000..fe4e56e613 --- /dev/null +++ b/source3/smbd/scavenger.c @@ -0,0 +1,531 @@ +/* + Unix SMB/CIFS implementation. + smbd scavenger daemon + + Copyright (C) Gregor Beck 2013 + + 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" + +#include "messages.h" +#include "serverid.h" +#include "smbd/globals.h" +#include "smbd/scavenger.h" +#include "locking/proto.h" +#include "lib/util/util_process.h" + +#undef DBGC_CLASS +#define DBGC_CLASS DBGC_SCAVENGER + +struct smbd_scavenger_state { + struct tevent_context *ev; + struct messaging_context *msg; + struct server_id parent_id; + struct server_id *scavenger_id; + bool am_scavenger; +}; + +static struct smbd_scavenger_state *smbd_scavenger_state = NULL; + +struct scavenger_message { + struct file_id file_id; + uint64_t open_persistent_id; + NTTIME until; +}; + +static int smbd_scavenger_main(struct smbd_scavenger_state *state) +{ + DEBUG(10, ("scavenger: %s started, parent: %s\n", + server_id_str(talloc_tos(), state->scavenger_id), + server_id_str(talloc_tos(), &state->parent_id))); + + while (true) { + TALLOC_CTX *frame = talloc_stackframe(); + int ret; + + ret = tevent_loop_once(state->ev); + if (ret != 0) { + DEBUG(2, ("tevent_loop_once failed: %s\n", + strerror(errno))); + TALLOC_FREE(frame); + return 1; + } + + DEBUG(10, ("scavenger: %s event loop iteration\n", + server_id_str(talloc_tos(), state->scavenger_id))); + TALLOC_FREE(frame); + } + + return 0; +} + +static void smbd_scavenger_done(struct tevent_context *event_ctx, struct tevent_fd *fde, + uint16_t flags, void *private_data) +{ + struct smbd_scavenger_state *state = talloc_get_type_abort( + private_data, struct smbd_scavenger_state); + + DEBUG(2, ("scavenger: %s died\n", + server_id_str(talloc_tos(), state->scavenger_id))); + + TALLOC_FREE(state->scavenger_id); +} + +static void smbd_scavenger_parent_dead(struct tevent_context *event_ctx, + struct tevent_fd *fde, + uint16_t flags, void *private_data) +{ + struct smbd_scavenger_state *state = talloc_get_type_abort( + private_data, struct smbd_scavenger_state); + + DEBUG(2, ("scavenger: %s parent %s died\n", + server_id_str(talloc_tos(), state->scavenger_id), + server_id_str(talloc_tos(), &state->parent_id))); + + exit_server("smbd_scavenger_parent_dead"); +} + +static void scavenger_sig_term_handler(struct tevent_context *ev, + struct tevent_signal *se, + int signum, + int count, + void *siginfo, + void *private_data) +{ + exit_server_cleanly("termination signal"); +} + +static void scavenger_setup_sig_term_handler(struct tevent_context *ev_ctx) +{ + struct tevent_signal *se; + + se = tevent_add_signal(ev_ctx, + ev_ctx, + SIGTERM, 0, + scavenger_sig_term_handler, + NULL); + if (se == NULL) { + exit_server("failed to setup SIGTERM handler"); + } +} + +static bool smbd_scavenger_running(struct smbd_scavenger_state *state) +{ + if (state->scavenger_id == NULL) { + return false; + } + + return serverid_exists(state->scavenger_id); +} + +static int smbd_scavenger_server_id_destructor(struct server_id *id) +{ + serverid_deregister(*id); + return 0; +} + +static bool scavenger_say_hello(int fd, struct server_id self) +{ + const uint8_t *msg = (const uint8_t *)&self; + size_t remaining = sizeof(self); + size_t ofs = 0; + + while (remaining > 0) { + ssize_t ret; + + ret = sys_write(fd, msg + ofs, remaining); + if (ret == -1) { + DEBUG(2, ("Failed to write to pipe: %s\n", + strerror(errno))); + return false; + } + remaining -= ret; + } + + DEBUG(4, ("scavenger_say_hello: self[%s]\n", + server_id_str(talloc_tos(), &self))); + return true; +} + +static bool scavenger_wait_hello(int fd, struct server_id *child) +{ + uint8_t *msg = (uint8_t *)child; + size_t remaining = sizeof(*child); + size_t ofs = 0; + + while (remaining > 0) { + ssize_t ret; + + ret = sys_read(fd, msg + ofs, remaining); + if (ret == -1) { + DEBUG(2, ("Failed to read from pipe: %s\n", + strerror(errno))); + return false; + } + remaining -= ret; + } + + DEBUG(4, ("scavenger_say_hello: child[%s]\n", + server_id_str(talloc_tos(), child))); + return true; +} + +static bool smbd_scavenger_start(struct smbd_scavenger_state *state) +{ + struct server_id self = messaging_server_id(state->msg); + struct tevent_fd *fde = NULL; + int fds[2]; + int ret; + uint64_t unique_id; + bool ok; + + SMB_ASSERT(server_id_equal(&state->parent_id, &self)); + + if (smbd_scavenger_running(state)) { + DEBUG(10, ("scavenger %s already running\n", + server_id_str(talloc_tos(), + state->scavenger_id))); + return true; + } + + if (state->scavenger_id != NULL) { + DEBUG(10, ("scavenger zombie %s, cleaning up\n", + server_id_str(talloc_tos(), + state->scavenger_id))); + TALLOC_FREE(state->scavenger_id); + } + + state->scavenger_id = talloc_zero(state, struct server_id); + if (state->scavenger_id == NULL) { + DEBUG(2, ("Out of memory\n")); + goto fail; + } + talloc_set_destructor(state->scavenger_id, + smbd_scavenger_server_id_destructor); + + ret = socketpair(AF_UNIX, SOCK_STREAM, 0, fds); + if (ret == -1) { + DEBUG(2, ("socketpair failed: %s", strerror(errno))); + goto fail; + } + + smb_set_close_on_exec(fds[0]); + smb_set_close_on_exec(fds[1]); + + unique_id = serverid_get_random_unique_id(); + + ret = fork(); + if (ret == -1) { + int err = errno; + close(fds[0]); + close(fds[1]); + DEBUG(0, ("fork failed: %s", strerror(err))); + goto fail; + } + + if (ret == 0) { + /* child */ + + NTSTATUS status; + + close(fds[0]); + + am_parent = NULL; + + set_my_unique_id(unique_id); + + status = reinit_after_fork(state->msg, state->ev, true); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(2, ("reinit_after_fork failed: %s\n", + nt_errstr(status))); + exit_server("reinit_after_fork failed"); + return false; + } + + prctl_set_comment("smbd-scavenger"); + + state->am_scavenger = true; + *state->scavenger_id = messaging_server_id(state->msg); + + scavenger_setup_sig_term_handler(state->ev); + + serverid_register(*state->scavenger_id, FLAG_MSG_GENERAL); + + ok = scavenger_say_hello(fds[1], *state->scavenger_id); + if (!ok) { + DEBUG(2, ("scavenger_say_hello failed\n")); + exit_server("scavenger_say_hello failed"); + return false; + } + + fde = tevent_add_fd(state->ev, state->scavenger_id, + fds[1], TEVENT_FD_READ, + smbd_scavenger_parent_dead, state); + if (fde == NULL) { + DEBUG(2, ("tevent_add_fd(smbd_scavenger_parent_dead) " + "failed\n")); + exit_server("tevent_add_fd(smbd_scavenger_parent_dead) " + "failed"); + return false; + } + tevent_fd_set_auto_close(fde); + + ret = smbd_scavenger_main(state); + + DEBUG(10, ("scavenger ended: %d\n", ret)); + exit_server_cleanly("scavenger ended"); + return false; + } + + /* parent */ + close(fds[1]); + + ok = scavenger_wait_hello(fds[0], state->scavenger_id); + if (!ok) { + close(fds[0]); + goto fail; + } + + fde = tevent_add_fd(state->ev, state->scavenger_id, + fds[0], TEVENT_FD_READ, + smbd_scavenger_done, state); + if (fde == NULL) { + close(fds[0]); + goto fail; + } + tevent_fd_set_auto_close(fde); + + return true; +fail: + TALLOC_FREE(state->scavenger_id); + return false; +} + +static void scavenger_add_timer(struct smbd_scavenger_state *state, + struct scavenger_message *msg); + +static void smbd_scavenger_msg(struct messaging_context *msg_ctx, + void *private_data, + uint32_t msg_type, + struct server_id src, + DATA_BLOB *data) +{ + struct smbd_scavenger_state *state = + talloc_get_type_abort(private_data, + struct smbd_scavenger_state); + TALLOC_CTX *frame = talloc_stackframe(); + struct server_id self = messaging_server_id(msg_ctx); + struct scavenger_message *msg = NULL; + + DEBUG(10, ("smbd_scavenger_msg: %s got message from %s\n", + server_id_str(talloc_tos(), &self), + server_id_str(talloc_tos(), &src))); + + if (server_id_equal(&state->parent_id, &self)) { + NTSTATUS status; + + if (!smbd_scavenger_running(state) && + !smbd_scavenger_start(state)) + { + DEBUG(2, ("Failed to start scavenger\n")); + goto done; + } + DEBUG(10, ("forwarding message to scavenger\n")); + + status = messaging_send(msg_ctx, + *state->scavenger_id, msg_type, data); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(2, ("forwarding message to scavenger failed: " + "%s\n", nt_errstr(status))); + goto done; + } + goto done; + } + + if (!state->am_scavenger) { + DEBUG(10, ("im not the scavenger: ignore message\n")); + goto done; + } + + if (!server_id_equal(&state->parent_id, &src)) { + DEBUG(10, ("scavenger: ignore spurious message\n")); + goto done; + } + + DEBUG(10, ("scavenger: got a message\n")); + msg = (struct scavenger_message*)data->data; + scavenger_add_timer(state, msg); +done: + talloc_free(frame); +} + +bool smbd_scavenger_init(TALLOC_CTX *mem_ctx, + struct messaging_context *msg, + struct tevent_context *ev) +{ + struct smbd_scavenger_state *state; + NTSTATUS status; + + if (smbd_scavenger_state) { + DEBUG(10, ("smbd_scavenger_init called again\n")); + return true; + } + + state = talloc_zero(mem_ctx, struct smbd_scavenger_state); + if (state == NULL) { + DEBUG(2, ("Out of memory\n")); + return false; + } + + state->msg = msg; + state->ev = ev; + state->parent_id = messaging_server_id(msg); + + status = messaging_register(msg, state, MSG_SMB_SCAVENGER, + smbd_scavenger_msg); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(2, ("failed to register message handler: %s\n", + nt_errstr(status))); + goto fail; + } + + smbd_scavenger_state = state; + return true; +fail: + talloc_free(state); + return false; +} + +void scavenger_schedule_disconnected(struct files_struct *fsp) +{ + NTSTATUS status; + struct server_id self = messaging_server_id(fsp->conn->sconn->msg_ctx); + struct timeval disconnect_time, until; + uint64_t timeout_usec; + struct scavenger_message msg; + DATA_BLOB msg_blob; + + nttime_to_timeval(&disconnect_time, fsp->op->global->disconnect_time); + timeout_usec = 1000 * fsp->op->global->durable_timeout_msec; + until = timeval_add(&disconnect_time, + timeout_usec / 1000000, + timeout_usec % 1000000); + + ZERO_STRUCT(msg); + msg.file_id = fsp->file_id; + msg.open_persistent_id = fsp->op->global->open_persistent_id; + msg.until = timeval_to_nttime(&until); + + DEBUG(10, ("smbd: %s mark file %s as disconnected at %s with timeout " + "at %s in %fs\n", + server_id_str(talloc_tos(), &self), + file_id_string_tos(&fsp->file_id), + timeval_string(talloc_tos(), &disconnect_time, true), + timeval_string(talloc_tos(), &until, true), + fsp->op->global->durable_timeout_msec/1000.0)); + + SMB_ASSERT(server_id_is_disconnected(&fsp->op->global->server_id)); + SMB_ASSERT(!server_id_equal(&self, &smbd_scavenger_state->parent_id)); + SMB_ASSERT(!smbd_scavenger_state->am_scavenger); + + msg_blob = data_blob_const(&msg, sizeof(msg)); + DEBUG(10, ("send message to scavenger\n")); + + status = messaging_send(smbd_scavenger_state->msg, + smbd_scavenger_state->parent_id, + MSG_SMB_SCAVENGER, + &msg_blob); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(2, ("Failed to send message to parent smbd %s " + "from %s: %s\n", + server_id_str(talloc_tos(), + &smbd_scavenger_state->parent_id), + server_id_str(talloc_tos(), &self), + nt_errstr(status))); + } +} + +struct scavenger_timer_context { + struct smbd_scavenger_state *state; + struct scavenger_message msg; +}; + +static void scavenger_timer(struct tevent_context *ev, + struct tevent_timer *te, + struct timeval t, void *data) +{ + struct scavenger_timer_context *ctx = + talloc_get_type_abort(data, struct scavenger_timer_context); + NTSTATUS status; + bool ok; + + DEBUG(10, ("scavenger: do cleanup for file %s at %s\n", + file_id_string_tos(&ctx->msg.file_id), + timeval_string(talloc_tos(), &t, true))); + + ok = share_mode_cleanup_disconnected(ctx->msg.file_id, + ctx->msg.open_persistent_id); + if (!ok) { + DEBUG(2, ("Failed to cleanup share modes and byte range locks " + "for file %s open %lu\n", + file_id_string_tos(&ctx->msg.file_id), + ctx->msg.open_persistent_id)); + } + + status = smbXsrv_open_cleanup(ctx->msg.open_persistent_id); + if (!NT_STATUS_IS_OK(status)) { + DEBUG(2, ("Failed to cleanup open global for file %s open %lu:" + " %s\n", file_id_string_tos(&ctx->msg.file_id), + ctx->msg.open_persistent_id, nt_errstr(status))); + } +} + +static void scavenger_add_timer(struct smbd_scavenger_state *state, + struct scavenger_message *msg) +{ + struct tevent_timer *te; + struct scavenger_timer_context *ctx; + struct timeval until; + + nttime_to_timeval(&until, msg->until); + + DEBUG(10, ("scavenger: schedule file %s for cleanup at %s\n", + file_id_string_tos(&msg->file_id), + timeval_string(talloc_tos(), &until, true))); + + ctx = talloc_zero(state, struct scavenger_timer_context); + if (ctx == NULL) { + DEBUG(2, ("Failed to talloc_zero(scavenger_timer_context)\n")); + return; + } + + ctx->state = state; + ctx->msg = *msg; + + te = tevent_add_timer(state->ev, + state, + until, + scavenger_timer, + ctx); + if (te == NULL) { + DEBUG(2, ("Failed to add scavenger_timer event\n")); + talloc_free(ctx); + return; + } + + /* delete context after handler was running */ + talloc_steal(te, ctx); +} |