freebsd-dev/lib/libc/net/nscachedcli.c
Pedro F. Giffuni d915a14ef0 libc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-25 17:12:48 +00:00

580 lines
14 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/event.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "un-namespace.h"
#include "nscachedcli.h"
#define NS_DEFAULT_CACHED_IO_TIMEOUT 4
static int safe_write(struct cached_connection_ *, const void *, size_t);
static int safe_read(struct cached_connection_ *, void *, size_t);
static int send_credentials(struct cached_connection_ *, int);
/*
* safe_write writes data to the specified connection and tries to do it in
* the very safe manner. We ensure, that we can write to the socket with
* kevent. If the data_size can't be sent in one piece, then it would be
* splitted.
*/
static int
safe_write(struct cached_connection_ *connection, const void *data,
size_t data_size)
{
struct kevent eventlist;
int nevents;
size_t result;
ssize_t s_result;
struct timespec timeout;
if (data_size == 0)
return (0);
timeout.tv_sec = NS_DEFAULT_CACHED_IO_TIMEOUT;
timeout.tv_nsec = 0;
result = 0;
do {
nevents = _kevent(connection->write_queue, NULL, 0, &eventlist,
1, &timeout);
if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
s_result = _sendto(connection->sockfd, data + result,
eventlist.data < data_size - result ?
eventlist.data : data_size - result, MSG_NOSIGNAL,
NULL, 0);
if (s_result == -1)
return (-1);
else
result += s_result;
if (eventlist.flags & EV_EOF)
return (result < data_size ? -1 : 0);
} else
return (-1);
} while (result < data_size);
return (0);
}
/*
* safe_read reads data from connection and tries to do it in the very safe
* and stable way. It uses kevent to ensure, that the data are available for
* reading. If the amount of data to be read is too large, then they would
* be splitted.
*/
static int
safe_read(struct cached_connection_ *connection, void *data, size_t data_size)
{
struct kevent eventlist;
size_t result;
ssize_t s_result;
struct timespec timeout;
int nevents;
if (data_size == 0)
return (0);
timeout.tv_sec = NS_DEFAULT_CACHED_IO_TIMEOUT;
timeout.tv_nsec = 0;
result = 0;
do {
nevents = _kevent(connection->read_queue, NULL, 0, &eventlist,
1, &timeout);
if (nevents == 1 && eventlist.filter == EVFILT_READ) {
s_result = _read(connection->sockfd, data + result,
eventlist.data <= data_size - result ?
eventlist.data : data_size - result);
if (s_result == -1)
return (-1);
else
result += s_result;
if (eventlist.flags & EV_EOF)
return (result < data_size ? -1 : 0);
} else
return (-1);
} while (result < data_size);
return (0);
}
/*
* Sends the credentials information to the connection along with the
* communication element type.
*/
static int
send_credentials(struct cached_connection_ *connection, int type)
{
struct kevent eventlist;
int nevents;
ssize_t result;
int res;
struct msghdr cred_hdr;
struct iovec iov;
struct {
struct cmsghdr hdr;
char cred[CMSG_SPACE(sizeof(struct cmsgcred))];
} cmsg;
memset(&cmsg, 0, sizeof(cmsg));
cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(struct cmsgcred));
cmsg.hdr.cmsg_level = SOL_SOCKET;
cmsg.hdr.cmsg_type = SCM_CREDS;
memset(&cred_hdr, 0, sizeof(struct msghdr));
cred_hdr.msg_iov = &iov;
cred_hdr.msg_iovlen = 1;
cred_hdr.msg_control = (caddr_t)&cmsg;
cred_hdr.msg_controllen = CMSG_SPACE(sizeof(struct cmsgcred));
iov.iov_base = &type;
iov.iov_len = sizeof(int);
EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
NOTE_LOWAT, sizeof(int), NULL);
res = _kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
nevents = _kevent(connection->write_queue, NULL, 0, &eventlist, 1,
NULL);
if (nevents == 1 && eventlist.filter == EVFILT_WRITE) {
result = (_sendmsg(connection->sockfd, &cred_hdr,
MSG_NOSIGNAL) == -1) ? -1 : 0;
EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
0, 0, NULL);
_kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
return (result);
} else
return (-1);
}
/*
* Opens the connection with the specified params. Initializes all kqueues.
*/
struct cached_connection_ *
__open_cached_connection(struct cached_connection_params const *params)
{
struct cached_connection_ *retval;
struct kevent eventlist;
struct sockaddr_un client_address;
int client_address_len, client_socket;
int res;
assert(params != NULL);
client_socket = _socket(PF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0);
client_address.sun_family = PF_LOCAL;
strncpy(client_address.sun_path, params->socket_path,
sizeof(client_address.sun_path));
client_address_len = sizeof(client_address.sun_family) +
strlen(client_address.sun_path) + 1;
res = _connect(client_socket, (struct sockaddr *)&client_address,
client_address_len);
if (res == -1) {
_close(client_socket);
return (NULL);
}
_fcntl(client_socket, F_SETFL, O_NONBLOCK);
retval = malloc(sizeof(struct cached_connection_));
assert(retval != NULL);
memset(retval, 0, sizeof(struct cached_connection_));
retval->sockfd = client_socket;
retval->write_queue = kqueue();
assert(retval->write_queue != -1);
EV_SET(&eventlist, retval->sockfd, EVFILT_WRITE, EV_ADD, 0, 0, NULL);
res = _kevent(retval->write_queue, &eventlist, 1, NULL, 0, NULL);
retval->read_queue = kqueue();
assert(retval->read_queue != -1);
EV_SET(&eventlist, retval->sockfd, EVFILT_READ, EV_ADD, 0, 0, NULL);
res = _kevent(retval->read_queue, &eventlist, 1, NULL, 0, NULL);
return (retval);
}
void
__close_cached_connection(struct cached_connection_ *connection)
{
assert(connection != NULL);
_close(connection->sockfd);
_close(connection->read_queue);
_close(connection->write_queue);
free(connection);
}
/*
* This function is very close to the cache_write function of the caching
* library, which is used in the caching daemon. It caches the data with the
* specified key in the cache entry with entry_name.
*/
int
__cached_write(struct cached_connection_ *connection, const char *entry_name,
const char *key, size_t key_size, const char *data, size_t data_size)
{
size_t name_size;
int error_code;
int result;
error_code = -1;
result = 0;
result = send_credentials(connection, CET_WRITE_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &key_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &data_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_write(connection, key, key_size);
if (result != 0)
goto fin;
result = safe_write(connection, data, data_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
error_code = -1;
fin:
return (error_code);
}
/*
* This function is very close to the cache_read function of the caching
* library, which is used in the caching daemon. It reads cached data with the
* specified key from the cache entry with entry_name.
*/
int
__cached_read(struct cached_connection_ *connection, const char *entry_name,
const char *key, size_t key_size, char *data, size_t *data_size)
{
size_t name_size, result_size;
int error_code, rec_error_code;
int result;
assert(connection != NULL);
result = 0;
error_code = -1;
result = send_credentials(connection, CET_READ_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &key_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_write(connection, key, key_size);
if (result != 0)
goto fin;
result = safe_read(connection, &rec_error_code, sizeof(int));
if (result != 0)
goto fin;
if (rec_error_code != 0) {
error_code = rec_error_code;
goto fin;
}
result = safe_read(connection, &result_size, sizeof(size_t));
if (result != 0)
goto fin;
if (result_size > *data_size) {
*data_size = result_size;
error_code = -2;
goto fin;
}
result = safe_read(connection, data, result_size);
if (result != 0)
goto fin;
*data_size = result_size;
error_code = 0;
fin:
return (error_code);
}
/*
* Initializes the mp_write_session. For such a session the new connection
* would be opened. The data should be written to the session with
* __cached_mp_write function. The __close_cached_mp_write_session function
* should be used to submit session and __abandon_cached_mp_write_session - to
* abandon it. When the session is submitted, the whole se
*/
struct cached_connection_ *
__open_cached_mp_write_session(struct cached_connection_params const *params,
const char *entry_name)
{
struct cached_connection_ *connection, *retval;
size_t name_size;
int error_code;
int result;
retval = NULL;
connection = __open_cached_connection(params);
if (connection == NULL)
return (NULL);
connection->mp_flag = 1;
result = send_credentials(connection, CET_MP_WRITE_SESSION_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
goto fin;
if (error_code != 0)
result = error_code;
fin:
if (result != 0)
__close_cached_connection(connection);
else
retval = connection;
return (retval);
}
/*
* Adds new portion of data to the opened write session
*/
int
__cached_mp_write(struct cached_connection_ *ws, const char *data,
size_t data_size)
{
int request, result;
int error_code;
error_code = -1;
request = CET_MP_WRITE_SESSION_WRITE_REQUEST;
result = safe_write(ws, &request, sizeof(int));
if (result != 0)
goto fin;
result = safe_write(ws, &data_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(ws, data, data_size);
if (result != 0)
goto fin;
result = safe_read(ws, &error_code, sizeof(int));
if (result != 0)
error_code = -1;
fin:
return (error_code);
}
/*
* Abandons all operations with the write session. All data, that were written
* to the session before, are discarded.
*/
int
__abandon_cached_mp_write_session(struct cached_connection_ *ws)
{
int notification;
int result;
notification = CET_MP_WRITE_SESSION_ABANDON_NOTIFICATION;
result = safe_write(ws, &notification, sizeof(int));
__close_cached_connection(ws);
return (result);
}
/*
* Gracefully closes the write session. The data, that were previously written
* to the session, are committed.
*/
int
__close_cached_mp_write_session(struct cached_connection_ *ws)
{
int notification;
int result;
notification = CET_MP_WRITE_SESSION_CLOSE_NOTIFICATION;
result = safe_write(ws, &notification, sizeof(int));
__close_cached_connection(ws);
return (0);
}
struct cached_connection_ *
__open_cached_mp_read_session(struct cached_connection_params const *params,
const char *entry_name)
{
struct cached_connection_ *connection, *retval;
size_t name_size;
int error_code;
int result;
retval = NULL;
connection = __open_cached_connection(params);
if (connection == NULL)
return (NULL);
connection->mp_flag = 1;
result = send_credentials(connection, CET_MP_READ_SESSION_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
goto fin;
if (error_code != 0)
result = error_code;
fin:
if (result != 0)
__close_cached_connection(connection);
else
retval = connection;
return (retval);
}
int
__cached_mp_read(struct cached_connection_ *rs, char *data, size_t *data_size)
{
size_t result_size;
int error_code, rec_error_code;
int request, result;
error_code = -1;
request = CET_MP_READ_SESSION_READ_REQUEST;
result = safe_write(rs, &request, sizeof(int));
if (result != 0)
goto fin;
result = safe_read(rs, &rec_error_code, sizeof(int));
if (result != 0)
goto fin;
if (rec_error_code != 0) {
error_code = rec_error_code;
goto fin;
}
result = safe_read(rs, &result_size, sizeof(size_t));
if (result != 0)
goto fin;
if (result_size > *data_size) {
*data_size = result_size;
error_code = -2;
goto fin;
}
result = safe_read(rs, data, result_size);
if (result != 0)
goto fin;
*data_size = result_size;
error_code = 0;
fin:
return (error_code);
}
int
__close_cached_mp_read_session(struct cached_connection_ *rs)
{
__close_cached_connection(rs);
return (0);
}