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-rw-r--r--lib/async_req/async_sock.c774
1 files changed, 774 insertions, 0 deletions
diff --git a/lib/async_req/async_sock.c b/lib/async_req/async_sock.c
new file mode 100644
index 0000000..bdbefd1
--- /dev/null
+++ b/lib/async_req/async_sock.c
@@ -0,0 +1,774 @@
+/*
+ Unix SMB/CIFS implementation.
+ async socket syscalls
+ Copyright (C) Volker Lendecke 2008
+
+ ** NOTE! The following LGPL license applies to the async_sock
+ ** library. This does NOT imply that all of Samba is released
+ ** under the LGPL
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3 of the License, or (at your option) any later version.
+
+ This library 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "replace.h"
+#include "system/network.h"
+#include "system/filesys.h"
+#include <talloc.h>
+#include <tevent.h>
+#include "lib/async_req/async_sock.h"
+#include "lib/util/iov_buf.h"
+#include "lib/util/util_net.h"
+
+/* Note: lib/util/ is currently GPL */
+#include "lib/util/tevent_unix.h"
+#include "lib/util/samba_util.h"
+
+struct async_connect_state {
+ int fd;
+ struct tevent_fd *fde;
+ int result;
+ long old_sockflags;
+ socklen_t address_len;
+ struct sockaddr_storage address;
+
+ void (*before_connect)(void *private_data);
+ void (*after_connect)(void *private_data);
+ void *private_data;
+};
+
+static void async_connect_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state);
+static void async_connect_connected(struct tevent_context *ev,
+ struct tevent_fd *fde, uint16_t flags,
+ void *priv);
+
+/**
+ * @brief async version of connect(2)
+ * @param[in] mem_ctx The memory context to hang the result off
+ * @param[in] ev The event context to work from
+ * @param[in] fd The socket to recv from
+ * @param[in] address Where to connect?
+ * @param[in] address_len Length of *address
+ * @retval The async request
+ *
+ * This function sets the socket into non-blocking state to be able to call
+ * connect in an async state. This will be reset when the request is finished.
+ */
+
+struct tevent_req *async_connect_send(
+ TALLOC_CTX *mem_ctx, struct tevent_context *ev, int fd,
+ const struct sockaddr *address, socklen_t address_len,
+ void (*before_connect)(void *private_data),
+ void (*after_connect)(void *private_data),
+ void *private_data)
+{
+ struct tevent_req *req;
+ struct async_connect_state *state;
+ int ret;
+
+ req = tevent_req_create(mem_ctx, &state, struct async_connect_state);
+ if (req == NULL) {
+ return NULL;
+ }
+
+ /**
+ * We have to set the socket to nonblocking for async connect(2). Keep
+ * the old sockflags around.
+ */
+
+ state->fd = fd;
+ state->before_connect = before_connect;
+ state->after_connect = after_connect;
+ state->private_data = private_data;
+
+ state->old_sockflags = fcntl(fd, F_GETFL, 0);
+ if (state->old_sockflags == -1) {
+ tevent_req_error(req, errno);
+ return tevent_req_post(req, ev);
+ }
+
+ tevent_req_set_cleanup_fn(req, async_connect_cleanup);
+
+ state->address_len = address_len;
+ if (address_len > sizeof(state->address)) {
+ tevent_req_error(req, EINVAL);
+ return tevent_req_post(req, ev);
+ }
+ memcpy(&state->address, address, address_len);
+
+ ret = set_blocking(fd, false);
+ if (ret == -1) {
+ tevent_req_error(req, errno);
+ return tevent_req_post(req, ev);
+ }
+
+ if (state->before_connect != NULL) {
+ state->before_connect(state->private_data);
+ }
+
+ state->result = connect(fd, address, address_len);
+
+ if (state->after_connect != NULL) {
+ state->after_connect(state->private_data);
+ }
+
+ if (state->result == 0) {
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+ }
+
+ /*
+ * The only errno indicating that an initial connect is still
+ * in flight is EINPROGRESS.
+ *
+ * This allows callers like open_socket_out_send() to reuse
+ * fds and call us with an fd for which the connect is still
+ * in flight. The proper thing to do for callers would be
+ * closing the fd and starting from scratch with a fresh
+ * socket.
+ */
+
+ if (errno != EINPROGRESS) {
+ tevent_req_error(req, errno);
+ return tevent_req_post(req, ev);
+ }
+
+ /*
+ * Note for historic reasons TEVENT_FD_WRITE is not enough
+ * to get notified for POLLERR or EPOLLHUP even if they
+ * come together with POLLOUT. That means we need to
+ * use TEVENT_FD_READ in addition until we have
+ * TEVENT_FD_ERROR.
+ */
+ state->fde = tevent_add_fd(ev, state, fd,
+ TEVENT_FD_ERROR|TEVENT_FD_WRITE,
+ async_connect_connected, req);
+ if (state->fde == NULL) {
+ tevent_req_error(req, ENOMEM);
+ return tevent_req_post(req, ev);
+ }
+ return req;
+}
+
+static void async_connect_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state)
+{
+ struct async_connect_state *state =
+ tevent_req_data(req, struct async_connect_state);
+
+ TALLOC_FREE(state->fde);
+ if (state->fd != -1) {
+ int ret;
+
+ ret = fcntl(state->fd, F_SETFL, state->old_sockflags);
+ if (ret == -1) {
+ abort();
+ }
+
+ state->fd = -1;
+ }
+}
+
+/**
+ * fde event handler for connect(2)
+ * @param[in] ev The event context that sent us here
+ * @param[in] fde The file descriptor event associated with the connect
+ * @param[in] flags Indicate read/writeability of the socket
+ * @param[in] priv private data, "struct async_req *" in this case
+ */
+
+static void async_connect_connected(struct tevent_context *ev,
+ struct tevent_fd *fde, uint16_t flags,
+ void *priv)
+{
+ struct tevent_req *req = talloc_get_type_abort(
+ priv, struct tevent_req);
+ struct async_connect_state *state =
+ tevent_req_data(req, struct async_connect_state);
+ int ret;
+ int socket_error = 0;
+ socklen_t slen = sizeof(socket_error);
+
+ ret = getsockopt(state->fd, SOL_SOCKET, SO_ERROR,
+ &socket_error, &slen);
+
+ if (ret != 0) {
+ /*
+ * According to Stevens this is the Solaris behaviour
+ * in case the connection encountered an error:
+ * getsockopt() fails, error is in errno
+ */
+ tevent_req_error(req, errno);
+ return;
+ }
+
+ if (socket_error != 0) {
+ /*
+ * Berkeley derived implementations (including) Linux
+ * return the pending error via socket_error.
+ */
+ tevent_req_error(req, socket_error);
+ return;
+ }
+
+ tevent_req_done(req);
+ return;
+}
+
+int async_connect_recv(struct tevent_req *req, int *perrno)
+{
+ int err = tevent_req_simple_recv_unix(req);
+
+ if (err != 0) {
+ *perrno = err;
+ return -1;
+ }
+
+ return 0;
+}
+
+struct writev_state {
+ struct tevent_context *ev;
+ struct tevent_queue_entry *queue_entry;
+ int fd;
+ struct tevent_fd *fde;
+ struct iovec *iov;
+ int count;
+ size_t total_size;
+ uint16_t flags;
+ bool err_on_readability;
+};
+
+static void writev_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state);
+static bool writev_cancel(struct tevent_req *req);
+static void writev_trigger(struct tevent_req *req, void *private_data);
+static void writev_handler(struct tevent_context *ev, struct tevent_fd *fde,
+ uint16_t flags, void *private_data);
+
+struct tevent_req *writev_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
+ struct tevent_queue *queue, int fd,
+ bool err_on_readability,
+ struct iovec *iov, int count)
+{
+ struct tevent_req *req;
+ struct writev_state *state;
+
+ req = tevent_req_create(mem_ctx, &state, struct writev_state);
+ if (req == NULL) {
+ return NULL;
+ }
+ state->ev = ev;
+ state->fd = fd;
+ state->total_size = 0;
+ state->count = count;
+ state->iov = (struct iovec *)talloc_memdup(
+ state, iov, sizeof(struct iovec) * count);
+ if (tevent_req_nomem(state->iov, req)) {
+ return tevent_req_post(req, ev);
+ }
+ state->flags = TEVENT_FD_WRITE | TEVENT_FD_ERROR;
+ if (err_on_readability) {
+ state->flags |= TEVENT_FD_READ;
+ }
+
+ tevent_req_set_cleanup_fn(req, writev_cleanup);
+ tevent_req_set_cancel_fn(req, writev_cancel);
+
+ if (queue == NULL) {
+ state->fde = tevent_add_fd(state->ev, state, state->fd,
+ state->flags, writev_handler, req);
+ if (tevent_req_nomem(state->fde, req)) {
+ return tevent_req_post(req, ev);
+ }
+ return req;
+ }
+
+ /*
+ * writev_trigger tries a nonblocking write. If that succeeds,
+ * we can't directly notify the callback to call
+ * writev_recv. The callback would TALLOC_FREE(req) after
+ * calling writev_recv even before writev_trigger can inspect
+ * it for success.
+ */
+ tevent_req_defer_callback(req, ev);
+
+ state->queue_entry = tevent_queue_add_optimize_empty(
+ queue, ev, req, writev_trigger, NULL);
+ if (tevent_req_nomem(state->queue_entry, req)) {
+ return tevent_req_post(req, ev);
+ }
+ if (!tevent_req_is_in_progress(req)) {
+ return tevent_req_post(req, ev);
+ }
+ return req;
+}
+
+static void writev_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state)
+{
+ struct writev_state *state = tevent_req_data(req, struct writev_state);
+
+ TALLOC_FREE(state->queue_entry);
+ TALLOC_FREE(state->fde);
+}
+
+static bool writev_cancel(struct tevent_req *req)
+{
+ struct writev_state *state = tevent_req_data(req, struct writev_state);
+
+ if (state->total_size > 0) {
+ /*
+ * We've already started to write :-(
+ */
+ return false;
+ }
+
+ TALLOC_FREE(state->queue_entry);
+ TALLOC_FREE(state->fde);
+
+ tevent_req_defer_callback(req, state->ev);
+ tevent_req_error(req, ECANCELED);
+ return true;
+}
+
+static void writev_do(struct tevent_req *req, struct writev_state *state)
+{
+ ssize_t written;
+ bool ok;
+
+ written = writev(state->fd, state->iov, state->count);
+ if ((written == -1) &&
+ ((errno == EINTR) ||
+ (errno == EAGAIN) ||
+ (errno == EWOULDBLOCK))) {
+ /* retry after going through the tevent loop */
+ return;
+ }
+ if (written == -1) {
+ tevent_req_error(req, errno);
+ return;
+ }
+ if (written == 0) {
+ tevent_req_error(req, EPIPE);
+ return;
+ }
+ state->total_size += written;
+
+ ok = iov_advance(&state->iov, &state->count, written);
+ if (!ok) {
+ tevent_req_error(req, EIO);
+ return;
+ }
+
+ if (state->count == 0) {
+ tevent_req_done(req);
+ return;
+ }
+}
+
+static void writev_trigger(struct tevent_req *req, void *private_data)
+{
+ struct writev_state *state = tevent_req_data(req, struct writev_state);
+
+ state->queue_entry = NULL;
+
+ writev_do(req, state);
+ if (!tevent_req_is_in_progress(req)) {
+ return;
+ }
+
+ state->fde = tevent_add_fd(state->ev, state, state->fd, state->flags,
+ writev_handler, req);
+ if (tevent_req_nomem(state->fde, req)) {
+ return;
+ }
+}
+
+static void writev_handler(struct tevent_context *ev, struct tevent_fd *fde,
+ uint16_t flags, void *private_data)
+{
+ struct tevent_req *req = talloc_get_type_abort(
+ private_data, struct tevent_req);
+ struct writev_state *state =
+ tevent_req_data(req, struct writev_state);
+
+ if (flags & TEVENT_FD_ERROR) {
+ /*
+ * There's an error, for legacy reasons
+ * we just use EPIPE instead of a more
+ * detailed error using
+ * samba_socket_poll_or_sock_error().
+ */
+ tevent_req_error(req, EPIPE);
+ return;
+ }
+
+ if (flags & TEVENT_FD_READ) {
+ /* Readable and the caller wants an error on read. */
+ tevent_req_error(req, EPIPE);
+ return;
+ }
+
+ writev_do(req, state);
+}
+
+ssize_t writev_recv(struct tevent_req *req, int *perrno)
+{
+ struct writev_state *state =
+ tevent_req_data(req, struct writev_state);
+ ssize_t ret;
+
+ if (tevent_req_is_unix_error(req, perrno)) {
+ tevent_req_received(req);
+ return -1;
+ }
+ ret = state->total_size;
+ tevent_req_received(req);
+ return ret;
+}
+
+struct read_packet_state {
+ int fd;
+ struct tevent_fd *fde;
+ uint8_t *buf;
+ size_t nread;
+ ssize_t (*more)(uint8_t *buf, size_t buflen, void *private_data);
+ void *private_data;
+};
+
+static void read_packet_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state);
+static void read_packet_handler(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags, void *private_data);
+
+struct tevent_req *read_packet_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ int fd, size_t initial,
+ ssize_t (*more)(uint8_t *buf,
+ size_t buflen,
+ void *private_data),
+ void *private_data)
+{
+ struct tevent_req *req;
+ struct read_packet_state *state;
+
+ req = tevent_req_create(mem_ctx, &state, struct read_packet_state);
+ if (req == NULL) {
+ return NULL;
+ }
+ state->fd = fd;
+ state->nread = 0;
+ state->more = more;
+ state->private_data = private_data;
+
+ tevent_req_set_cleanup_fn(req, read_packet_cleanup);
+
+ state->buf = talloc_array(state, uint8_t, initial);
+ if (tevent_req_nomem(state->buf, req)) {
+ return tevent_req_post(req, ev);
+ }
+
+ state->fde = tevent_add_fd(ev, state, fd,
+ TEVENT_FD_READ, read_packet_handler,
+ req);
+ if (tevent_req_nomem(state->fde, req)) {
+ return tevent_req_post(req, ev);
+ }
+ return req;
+}
+
+static void read_packet_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state)
+{
+ struct read_packet_state *state =
+ tevent_req_data(req, struct read_packet_state);
+
+ TALLOC_FREE(state->fde);
+}
+
+static void read_packet_handler(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags, void *private_data)
+{
+ struct tevent_req *req = talloc_get_type_abort(
+ private_data, struct tevent_req);
+ struct read_packet_state *state =
+ tevent_req_data(req, struct read_packet_state);
+ size_t total = talloc_get_size(state->buf);
+ ssize_t nread, more;
+ uint8_t *tmp;
+
+ nread = recv(state->fd, state->buf+state->nread, total-state->nread,
+ 0);
+ if ((nread == -1) && (errno == ENOTSOCK)) {
+ nread = read(state->fd, state->buf+state->nread,
+ total-state->nread);
+ }
+ if ((nread == -1) && (errno == EINTR)) {
+ /* retry */
+ return;
+ }
+ if (nread == -1) {
+ tevent_req_error(req, errno);
+ return;
+ }
+ if (nread == 0) {
+ tevent_req_error(req, EPIPE);
+ return;
+ }
+
+ state->nread += nread;
+ if (state->nread < total) {
+ /* Come back later */
+ return;
+ }
+
+ /*
+ * We got what was initially requested. See if "more" asks for -- more.
+ */
+ if (state->more == NULL) {
+ /* Nobody to ask, this is a async read_data */
+ tevent_req_done(req);
+ return;
+ }
+
+ more = state->more(state->buf, total, state->private_data);
+ if (more == -1) {
+ /* We got an invalid packet, tell the caller */
+ tevent_req_error(req, EIO);
+ return;
+ }
+ if (more == 0) {
+ /* We're done, full packet received */
+ tevent_req_done(req);
+ return;
+ }
+
+ if (total + more < total) {
+ tevent_req_error(req, EMSGSIZE);
+ return;
+ }
+
+ tmp = talloc_realloc(state, state->buf, uint8_t, total+more);
+ if (tevent_req_nomem(tmp, req)) {
+ return;
+ }
+ state->buf = tmp;
+}
+
+ssize_t read_packet_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+ uint8_t **pbuf, int *perrno)
+{
+ struct read_packet_state *state =
+ tevent_req_data(req, struct read_packet_state);
+
+ if (tevent_req_is_unix_error(req, perrno)) {
+ tevent_req_received(req);
+ return -1;
+ }
+ *pbuf = talloc_move(mem_ctx, &state->buf);
+ tevent_req_received(req);
+ return talloc_get_size(*pbuf);
+}
+
+struct wait_for_read_state {
+ struct tevent_fd *fde;
+ int fd;
+ bool check_errors;
+};
+
+static void wait_for_read_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state);
+static void wait_for_read_done(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags,
+ void *private_data);
+
+struct tevent_req *wait_for_read_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev, int fd,
+ bool check_errors)
+{
+ struct tevent_req *req;
+ struct wait_for_read_state *state;
+
+ req = tevent_req_create(mem_ctx, &state, struct wait_for_read_state);
+ if (req == NULL) {
+ return NULL;
+ }
+
+ tevent_req_set_cleanup_fn(req, wait_for_read_cleanup);
+
+ state->fde = tevent_add_fd(ev, state, fd, TEVENT_FD_READ,
+ wait_for_read_done, req);
+ if (tevent_req_nomem(state->fde, req)) {
+ return tevent_req_post(req, ev);
+ }
+
+ state->fd = fd;
+ state->check_errors = check_errors;
+ return req;
+}
+
+static void wait_for_read_cleanup(struct tevent_req *req,
+ enum tevent_req_state req_state)
+{
+ struct wait_for_read_state *state =
+ tevent_req_data(req, struct wait_for_read_state);
+
+ TALLOC_FREE(state->fde);
+}
+
+static void wait_for_read_done(struct tevent_context *ev,
+ struct tevent_fd *fde,
+ uint16_t flags,
+ void *private_data)
+{
+ struct tevent_req *req = talloc_get_type_abort(
+ private_data, struct tevent_req);
+ struct wait_for_read_state *state =
+ tevent_req_data(req, struct wait_for_read_state);
+ int ret, available;
+
+ if ((flags & TEVENT_FD_READ) == 0) {
+ return;
+ }
+
+ if (!state->check_errors) {
+ tevent_req_done(req);
+ return;
+ }
+
+ ret = ioctl(state->fd, FIONREAD, &available);
+
+ if ((ret == -1) && (errno == EINTR)) {
+ /* come back later */
+ return;
+ }
+
+ if (ret == -1) {
+ tevent_req_error(req, errno);
+ return;
+ }
+
+ if (available == 0) {
+ tevent_req_error(req, EPIPE);
+ return;
+ }
+
+ tevent_req_done(req);
+}
+
+bool wait_for_read_recv(struct tevent_req *req, int *perr)
+{
+ int err = tevent_req_simple_recv_unix(req);
+
+ if (err != 0) {
+ *perr = err;
+ return false;
+ }
+
+ return true;
+}
+
+struct accept_state {
+ struct tevent_fd *fde;
+ int listen_sock;
+ struct samba_sockaddr addr;
+ int sock;
+};
+
+static void accept_handler(struct tevent_context *ev, struct tevent_fd *fde,
+ uint16_t flags, void *private_data);
+
+struct tevent_req *accept_send(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
+ int listen_sock)
+{
+ struct tevent_req *req;
+ struct accept_state *state;
+
+ req = tevent_req_create(mem_ctx, &state, struct accept_state);
+ if (req == NULL) {
+ return NULL;
+ }
+
+ state->listen_sock = listen_sock;
+
+ state->fde = tevent_add_fd(ev, state, listen_sock, TEVENT_FD_READ,
+ accept_handler, req);
+ if (tevent_req_nomem(state->fde, req)) {
+ return tevent_req_post(req, ev);
+ }
+ return req;
+}
+
+static void accept_handler(struct tevent_context *ev, struct tevent_fd *fde,
+ uint16_t flags, void *private_data)
+{
+ struct tevent_req *req = talloc_get_type_abort(
+ private_data, struct tevent_req);
+ struct accept_state *state = tevent_req_data(req, struct accept_state);
+ int ret;
+
+ TALLOC_FREE(state->fde);
+
+ if ((flags & TEVENT_FD_READ) == 0) {
+ tevent_req_error(req, EIO);
+ return;
+ }
+
+ state->addr.sa_socklen = sizeof(state->addr.u);
+
+ ret = accept(state->listen_sock,
+ &state->addr.u.sa,
+ &state->addr.sa_socklen);
+ if ((ret == -1) && (errno == EINTR)) {
+ /* retry */
+ return;
+ }
+ if (ret == -1) {
+ tevent_req_error(req, errno);
+ return;
+ }
+ smb_set_close_on_exec(ret);
+ state->sock = ret;
+ tevent_req_done(req);
+}
+
+int accept_recv(struct tevent_req *req,
+ int *listen_sock,
+ struct samba_sockaddr *paddr,
+ int *perr)
+{
+ struct accept_state *state = tevent_req_data(req, struct accept_state);
+ int sock = state->sock;
+ int err;
+
+ if (tevent_req_is_unix_error(req, &err)) {
+ if (perr != NULL) {
+ *perr = err;
+ }
+ tevent_req_received(req);
+ return -1;
+ }
+ if (listen_sock != NULL) {
+ *listen_sock = state->listen_sock;
+ }
+ if (paddr != NULL) {
+ *paddr = state->addr;
+ }
+ tevent_req_received(req);
+ return sock;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-09 08:59:07 +0000