mars/mars_net.c
2013-01-20 23:23:30 +01:00

789 lines
18 KiB
C

// (c) 2011 Thomas Schoebel-Theuer / 1&1 Internet AG
//#define BRICK_DEBUGGING
//#define MARS_DEBUGGING
//#define IO_DEBUGGING
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include "mars.h"
#include "mars_net.h"
static
void mars_check_meta(const struct meta *meta, void *data);
/* Low-level network traffic
*/
/* TODO: allow binding to specific source addresses instead of catch-all.
* TODO: make all the socket options configurable.
* TODO: implement signal handling.
* TODO: add authentication.
* TODO: add compression / encryption.
*/
struct mars_tcp_params default_tcp_params = {
.window_size = 8 * 1024 * 1024, // for long distance replications
.tcp_timeout = 20,
.tcp_keepcnt = 6,
.tcp_keepintvl = 10, // keepalive ping time
.tcp_keepidle = 10,
.tos = IPTOS_LOWDELAY,
};
EXPORT_SYMBOL(default_tcp_params);
static void _check(int status)
{
if (status < 0) {
MARS_WRN("cannot set socket option, status = %d\n", status);
}
}
int mars_create_sockaddr(struct sockaddr_storage *addr, const char *spec)
{
struct sockaddr_in *sockaddr = (void*)addr;
char *new_spec;
char *tmp_spec;
int status = 0;
memset(addr, 0, sizeof(*addr));
sockaddr->sin_family = AF_INET;
sockaddr->sin_port = htons(MARS_DEFAULT_PORT);
/* Try to translate hostnames to IPs if possible.
*/
if (mars_translate_hostname) {
new_spec = mars_translate_hostname(spec);
} else {
new_spec = brick_strdup(spec);
}
tmp_spec = new_spec;
/* This is PROVISIONARY!
* TODO: add IPV6 syntax and many more features :)
*/
if (!*tmp_spec)
goto done;
if (*tmp_spec != ':') {
unsigned char u0 = 0, u1 = 0, u2 = 0, u3 = 0;
status = sscanf(tmp_spec, "%hhu.%hhu.%hhu.%hhu", &u0, &u1, &u2, &u3);
if (status != 4) {
status = -EINVAL;
goto done;
}
sockaddr->sin_addr.s_addr = (__be32)u0 | (__be32)u1 << 8 | (__be32)u2 << 16 | (__be32)u3 << 24;
}
while (*tmp_spec && *tmp_spec++ != ':')
/*empty*/;
if (*tmp_spec) {
int port = 0;
status = sscanf(tmp_spec, "%d", &port);
if (status != 1) {
status = -EINVAL;
goto done;
}
sockaddr->sin_port = htons(port);
}
status = 0;
done:
brick_string_free(new_spec);
return status;
}
EXPORT_SYMBOL_GPL(mars_create_sockaddr);
/* The original struct socket has no refcount. This leads to problems
* during long-lasting system calls when racing with socket shutdown.
* This is just a small wrapper adding a refcount.
*/
struct mars_socket {
atomic_t s_count;
struct socket *s_socket;
bool s_dead;
};
struct mars_socket *mars_create_socket(struct sockaddr_storage *addr, bool is_server)
{
struct mars_socket *msock;
struct socket *sock;
struct sockaddr *sockaddr = (void*)addr;
int x_true = 1;
int status = -ENOMEM;
msock = brick_zmem_alloc(sizeof(struct mars_socket));
if (!msock)
goto done;
status = sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &msock->s_socket);
if (unlikely(status < 0)) {
MARS_WRN("cannot create socket, status = %d\n", status);
goto done;
}
atomic_set(&msock->s_count, 1);
sock = msock->s_socket;
status = -EINVAL;
CHECK_PTR(sock, done);
/* TODO: improve this by a table-driven approach
*/
sock->sk->sk_rcvtimeo = sock->sk->sk_sndtimeo = default_tcp_params.tcp_timeout * HZ;
status = kernel_setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (char*)&default_tcp_params.window_size, sizeof(default_tcp_params.window_size));
_check(status);
status = kernel_setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char*)&default_tcp_params.window_size, sizeof(default_tcp_params.window_size));
_check(status);
status = kernel_setsockopt(sock, SOL_IP, SO_PRIORITY, (char*)&default_tcp_params.tos, sizeof(default_tcp_params.tos));
_check(status);
#if 0
status = kernel_setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (char*)&x_true, sizeof(x_true));
#endif
_check(status);
status = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (char*)&x_true, sizeof(x_true));
_check(status);
status = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT, (char*)&default_tcp_params.tcp_keepcnt, sizeof(default_tcp_params.tcp_keepcnt));
_check(status);
status = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL, (char*)&default_tcp_params.tcp_keepintvl, sizeof(default_tcp_params.tcp_keepintvl));
_check(status);
status = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE, (char*)&default_tcp_params.tcp_keepidle, sizeof(default_tcp_params.tcp_keepidle));
_check(status);
if (is_server) {
status = kernel_bind(sock, sockaddr, sizeof(*sockaddr));
if (unlikely(status < 0)) {
MARS_WRN("bind failed, status = %d\n", status);
goto done;
}
status = kernel_listen(sock, 16);
if (status < 0) {
MARS_WRN("listen failed, status = %d\n", status);
}
} else {
status = kernel_connect(sock, sockaddr, sizeof(*sockaddr), 0);
if (status < 0) {
MARS_DBG("connect failed, status = %d\n", status);
}
}
done:
if (status < 0) {
mars_put_socket(msock);
msock = ERR_PTR(status);
}
return msock;
}
EXPORT_SYMBOL_GPL(mars_create_socket);
struct mars_socket *mars_accept_socket(struct mars_socket *msock, bool do_block)
{
int status = -ENOENT;
if (likely(msock)) {
struct mars_socket *new_msock;
struct socket *new_socket = NULL;
mars_get_socket(msock);
status = kernel_accept(msock->s_socket, &new_socket, do_block ? 0 : O_NONBLOCK);
mars_put_socket(msock);
if (unlikely(status < 0)) {
goto err;
}
if (unlikely(!new_socket)) {
status = -EBADF;
goto err;
}
#if 0 // do not use for now
if (!do_block && new_socket->file) { // switch back to blocking mode
new_socket->file->f_flags &= ~O_NONBLOCK;
}
#endif
status = -ENOMEM;
new_msock = brick_zmem_alloc(sizeof(struct mars_socket));
if (!new_msock) {
kernel_sock_shutdown(new_socket, SHUT_WR);
sock_release(new_socket);
goto err;
}
atomic_set(&new_msock->s_count, 1);
new_msock->s_socket = new_socket;
return new_msock;
}
err:
return ERR_PTR(status);
}
EXPORT_SYMBOL_GPL(mars_accept_socket);
struct mars_socket *mars_get_socket(struct mars_socket *msock)
{
if (likely(msock)) {
atomic_inc(&msock->s_count);
}
return msock;
}
EXPORT_SYMBOL_GPL(mars_get_socket);
void mars_put_socket(struct mars_socket *msock)
{
if (likely(msock)) {
if (atomic_dec_and_test(&msock->s_count)) {
struct socket *sock = msock->s_socket;
if (sock) {
if (!msock->s_dead) {
msock->s_dead = true;
kernel_sock_shutdown(sock, SHUT_WR);
}
sock_release(sock);
}
brick_mem_free(msock);
}
}
}
EXPORT_SYMBOL_GPL(mars_put_socket);
void mars_shutdown_socket(struct mars_socket *msock)
{
if (likely(msock)) {
struct socket *sock = msock->s_socket;
if (sock && !msock->s_dead) {
msock->s_dead = true;
kernel_sock_shutdown(sock, SHUT_WR);
}
}
}
EXPORT_SYMBOL_GPL(mars_shutdown_socket);
bool mars_socket_is_alive(struct mars_socket *msock)
{
if (!msock || msock->s_dead)
return false;
return true;
}
EXPORT_SYMBOL_GPL(mars_socket_is_alive);
int mars_send(struct mars_socket *msock, void *buf, int len)
{
struct kvec iov = {
.iov_base = buf,
.iov_len = len,
};
struct msghdr msg = {
.msg_iov = (struct iovec*)&iov,
.msg_flags = 0 | MSG_NOSIGNAL,
};
int status = -EIDRM;
int sent = 0;
if (!mars_get_socket(msock))
goto done;
//MARS_IO("buf = %p, len = %d\n", buf, len);
while (sent < len) {
if (unlikely(msock->s_dead)) {
MARS_WRN("socket has disappeared\n");
status = -EIDRM;
goto done;
}
status = kernel_sendmsg(msock->s_socket, &msg, &iov, 1, len);
if (status == -EAGAIN) {
msleep(50);
continue;
}
if (status == -EINTR) { // ignore it
flush_signals(current);
msleep(50);
continue;
}
if (status < 0) {
MARS_WRN("bad socket sendmsg, len=%d, iov_len=%d, sent=%d, status = %d\n", len, (int)iov.iov_len, sent, status);
goto done;
}
if (!status) {
MARS_WRN("EOF from socket upon sendmsg\n");
status = -ECOMM;
goto done;
}
iov.iov_base += status;
iov.iov_len -= status;
sent += status;
}
status = sent;
done:
mars_put_socket(msock);
return status;
}
EXPORT_SYMBOL_GPL(mars_send);
int mars_recv(struct mars_socket *msock, void *buf, int minlen, int maxlen)
{
int sleeptime = 1000 / HZ;
int status = -EIDRM;
int done = 0;
if (!buf) {
MARS_WRN("bad receive buffer\n");
return -EINVAL;
}
if (!mars_get_socket(msock))
goto err;
while (done < minlen) {
struct kvec iov = {
.iov_base = buf + done,
.iov_len = maxlen - done,
};
struct msghdr msg = {
.msg_iovlen = 1,
.msg_iov = (struct iovec*)&iov,
.msg_flags = 0 | MSG_WAITALL | MSG_NOSIGNAL,
};
if (unlikely(msock->s_dead)) {
MARS_WRN("socket has disappeared\n");
status = -EIDRM;
goto err;
}
MARS_IO("done %d, fetching %d bytes\n", done, maxlen-done);
status = kernel_recvmsg(msock->s_socket, &msg, &iov, 1, maxlen-done, msg.msg_flags);
if (status == -EAGAIN) {
// linearly increasing backoff
if (sleeptime < 100)
sleeptime++;
msleep(sleeptime);
continue;
}
if (!status) { // EOF
MARS_WRN("got EOF from socket (done=%d, req_size=%d)\n", done, maxlen - done);
status = -EPIPE;
goto err;
}
if (status < 0) {
MARS_WRN("bad recvmsg, status = %d\n", status);
goto err;
}
done += status;
sleeptime = 1000 / HZ;
}
status = done;
err:
mars_put_socket(msock);
return status;
}
EXPORT_SYMBOL_GPL(mars_recv);
///////////////////////////////////////////////////////////////////////
/* Mid-level field data exchange
*/
/* TODO: make this bytesex-aware
*/
#define MARS_NET_MAGIC 0x63f092ec6048f48cll
#define MAX_FIELD_LEN 32
struct mars_net_header {
u64 h_magic;
char h_name[MAX_FIELD_LEN];
u16 h_seq;
u16 h_len;
};
int _mars_send_struct(struct mars_socket *msock, void *data, const struct meta *meta, int *seq)
{
int count = 0;
int status = 0;
if (!data) { // send EOR
struct mars_net_header header = {
.h_magic = MARS_NET_MAGIC,
.h_seq = -1,
};
return mars_send(msock, &header, sizeof(header));
}
for (; ; meta++) {
struct mars_net_header header = {
.h_magic = MARS_NET_MAGIC,
.h_seq = ++(*seq),
};
void *item = data + meta->field_offset;
int len = meta->field_size;
#if 1
if (len > 16 * PAGE_SIZE) {
MARS_WRN("implausible len=%d, \n", len);
msleep(30000);
status = -EINVAL;
break;
}
#endif
/* Automatically keep the lamport clock correct.
*/
mars_check_meta(meta, data);
status = 0;
switch (meta->field_type) {
case FIELD_STRING:
item = *(void**)item;
len = 0;
if (item)
len = strlen(item) + 1;
break;
case FIELD_REF:
if (!meta->field_ref) {
MARS_WRN("improper FIELD_REF definition\n");
status = -EINVAL;
break;
}
item = *(void**)item;
len = meta->field_ref->field_size;
if (!item)
len = 0;
break;
case FIELD_DONE:
len = 0;
case FIELD_SUB:
case FIELD_RAW:
case FIELD_INT:
case FIELD_UINT:
// all ok
break;
default:
MARS_WRN("invalid field type %d\n", meta->field_type);
status = -EINVAL;
break;
}
if (status < 0)
break;
header.h_len = len;
if (meta->field_name) {
strncpy(header.h_name, meta->field_name, MAX_FIELD_LEN);
header.h_name[MAX_FIELD_LEN-1] = '\0';
}
MARS_IO("sending header %d '%s' len = %d\n", header.h_seq, header.h_name, len);
status = mars_send(msock, &header, sizeof(header));
if (status < 0 || !meta->field_name) { // EOR
break;
}
switch (meta->field_type) {
case FIELD_REF:
case FIELD_SUB:
status = _mars_send_struct(msock, item, meta->field_ref, seq);
if (status > 0)
count += status;
break;
default:
if (len > 0) {
MARS_IO("sending extra %d\n", len);
status = mars_send(msock, item, len);
if (status > 0)
count++;
}
}
if (status < 0) {
break;
}
}
if (status >= 0)
status = count;
return status;
}
int mars_send_struct(struct mars_socket *msock, void *data, const struct meta *meta)
{
int seq = 0;
return _mars_send_struct(msock, data, meta, &seq);
}
EXPORT_SYMBOL_GPL(mars_send_struct);
int _mars_recv_struct(struct mars_socket *msock, void *data, const struct meta *meta, int *seq, int line)
{
int count = 0;
int status = -EINVAL;
//MARS_IO("\n");
if (!data) {
goto done;
}
for (;;) {
struct mars_net_header header = {};
const struct meta *tmp;
void *item;
void *mem;
status = mars_recv(msock, &header, sizeof(header), sizeof(header));
if (status == -EAGAIN) {
msleep(50);
continue;
}
if (status < 0) {
MARS_WRN("status = %d\n", status);
break;
}
MARS_IO("got header %d '%s' len = %d\n", header.h_seq, header.h_name, header.h_len);
if (header.h_magic != MARS_NET_MAGIC) {
MARS_WRN("bad packet header magic = %llx\n", header.h_magic);
status = -ENOMSG;
break;
}
if (header.h_seq == -1) { // got EOR
status = 0;
break;
};
if (header.h_seq <= *seq) {
MARS_WRN("unexpected packet data, seq=%d (expected=%d)\n", header.h_seq, (*seq) + 1);
status = -ENOMSG;
break;
}
*seq = header.h_seq;
if (!header.h_name[0]) { // end of record (EOR)
status = 0;
break;
}
tmp = find_meta(meta, header.h_name);
if (!tmp) {
MARS_WRN("unknown field '%s'\n", header.h_name);
if (header.h_len > 0) { // try to continue by skipping the rest of data
void *dummy = brick_mem_alloc(header.h_len);
status = -ENOMEM;
if (!dummy)
break;
status = mars_recv(msock, dummy, header.h_len, header.h_len);
brick_mem_free(dummy);
if (status < 0)
break;
}
continue;
}
status = 0;
item = data + tmp->field_offset;
switch (tmp->field_type) {
case FIELD_REF:
case FIELD_STRING:
if (header.h_len <= 0) {
mem = NULL;
} else {
if (tmp->field_type == FIELD_STRING) {
mem = _brick_string_alloc(header.h_len + 1, line);
} else {
mem = brick_zmem_alloc(header.h_len + 1);
}
if (!mem) {
status = -ENOMEM;
goto done;
}
}
*(void**)item = mem;
item = mem;
break;
}
switch (tmp->field_type) {
case FIELD_REF:
case FIELD_SUB:
if (!item) {
MARS_WRN("bad item\n");
status = -EINVAL;
break;
}
MARS_IO("starting recursive structure\n");
status = _mars_recv_struct(msock, item, tmp->field_ref, seq, line);
MARS_IO("ending recursive structure, status = %d\n", status);
if (status > 0)
count += status;
break;
default:
if (header.h_len > 0) {
if (!item) {
MARS_WRN("bad item\n");
status = -EINVAL;
break;
}
MARS_IO("reading extra %d\n", header.h_len);
status = mars_recv(msock, item, header.h_len, header.h_len);
while (status == -EAGAIN) {
msleep(50);
status = mars_recv(msock, item, header.h_len, header.h_len);
}
if (status >= 0) {
//MARS_IO("got data len = %d status = %d\n", header.h_len, status);
count++;
} else {
MARS_WRN("len = %d, status = %d\n", header.h_len, status);
}
}
}
if (status < 0)
break;
}
done:
if (status >= 0) {
status = count;
mars_check_meta(meta, data);
} else {
MARS_WRN("status = %d\n", status);
}
return status;
}
EXPORT_SYMBOL_GPL(_mars_recv_struct);
///////////////////////////////////////////////////////////////////////
/* High-level transport of mars structures
*/
const struct meta mars_cmd_meta[] = {
META_INI_SUB(cmd_stamp, struct mars_cmd, mars_timespec_meta),
META_INI(cmd_code, struct mars_cmd, FIELD_INT),
META_INI(cmd_int1, struct mars_cmd, FIELD_INT),
META_INI(cmd_str1, struct mars_cmd, FIELD_STRING),
{}
};
EXPORT_SYMBOL_GPL(mars_cmd_meta);
static
void mars_check_meta(const struct meta *meta, void *data)
{
/* Automatically keep the lamport clock correct.
*/
if (meta == mars_cmd_meta) {
struct timespec *stamp = &((struct mars_cmd*)data)->cmd_stamp;
get_lamport(stamp);
} else if (meta == mars_timespec_meta) {
set_lamport(data);
}
}
int mars_send_mref(struct mars_socket *msock, struct mref_object *mref)
{
struct mars_cmd cmd = {
.cmd_code = CMD_MREF,
.cmd_int1 = mref->ref_id,
};
int status;
status = mars_send_struct(msock, &cmd, mars_cmd_meta);
if (status < 0)
goto done;
status = mars_send_struct(msock, mref, mars_mref_meta);
if (status < 0)
goto done;
if (mref->ref_rw) {
status = mars_send(msock, mref->ref_data, mref->ref_len);
}
done:
return status;
}
EXPORT_SYMBOL_GPL(mars_send_mref);
int mars_recv_mref(struct mars_socket *msock, struct mref_object *mref)
{
int status;
status = mars_recv_struct(msock, mref, mars_mref_meta);
if (status < 0)
goto done;
if (mref->ref_rw) {
if (!mref->ref_data)
mref->ref_data = brick_zmem_alloc(mref->ref_len);
if (!mref->ref_data) {
status = -ENOMEM;
goto done;
}
status = mars_recv(msock, mref->ref_data, mref->ref_len, mref->ref_len);
if (status < 0)
MARS_WRN("mref_len = %d, status = %d\n", mref->ref_len, status);
}
done:
return status;
}
EXPORT_SYMBOL_GPL(mars_recv_mref);
int mars_send_cb(struct mars_socket *msock, struct mref_object *mref)
{
struct mars_cmd cmd = {
.cmd_code = CMD_CB,
.cmd_int1 = mref->ref_id,
};
int status;
status = mars_send_struct(msock, &cmd, mars_cmd_meta);
if (status < 0)
goto done;
status = mars_send_struct(msock, mref, mars_mref_meta);
if (status < 0)
goto done;
if (!mref->ref_rw) {
MARS_IO("sending blocklen = %d\n", mref->ref_len);
status = mars_send(msock, mref->ref_data, mref->ref_len);
}
done:
return status;
}
EXPORT_SYMBOL_GPL(mars_send_cb);
int mars_recv_cb(struct mars_socket *msock, struct mref_object *mref)
{
int status;
status = mars_recv_struct(msock, mref, mars_mref_meta);
if (status < 0)
goto done;
if (!mref->ref_rw) {
if (!mref->ref_data) {
MARS_WRN("no internal buffer available\n");
status = -EINVAL;
goto done;
}
MARS_IO("receiving blocklen = %d\n", mref->ref_len);
status = mars_recv(msock, mref->ref_data, mref->ref_len, mref->ref_len);
}
done:
return status;
}
EXPORT_SYMBOL_GPL(mars_recv_cb);
////////////////// module init stuff /////////////////////////
char *(*mars_translate_hostname)(const char *name) = NULL;
EXPORT_SYMBOL_GPL(mars_translate_hostname);
int __init init_mars_net(void)
{
MARS_INF("init_net()\n");
return 0;
}
void __exit exit_mars_net(void)
{
MARS_INF("exit_net()\n");
}
#ifndef CONFIG_MARS_HAVE_BIGMODULE
MODULE_DESCRIPTION("MARS network infrastructure");
MODULE_AUTHOR("Thomas Schoebel-Theuer <tst@1und1.de>");
MODULE_LICENSE("GPL");
module_init(init_mars_net);
module_exit(exit_mars_net);
#endif