static void ns_read_from_socket(struct ns_connection *conn) {
char buf[NS_READ_BUFFER_SIZE];
int n = 0;
if (conn->flags & NSF_CONNECTING) {
int ok = 1, ret;
(void) ret;
socklen_t len = sizeof(ok);
ret = getsockopt(conn->sock, SOL_SOCKET, SO_ERROR, (char *) &ok, &len);
#ifdef NS_ENABLE_SSL
if (ret == 0 && ok == 0 && conn->ssl != NULL) {
ns_ssl_begin(conn);
}
#endif
DBG(("%p connect ok=%d", conn, ok));
if (ok != 0) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
} else {
conn->flags &= ~NSF_CONNECTING;
}
ns_call(conn, NS_CONNECT, &ok);
return;
}
#ifdef NS_ENABLE_SSL
if (conn->ssl != NULL) {
if (conn->flags & NSF_SSL_HANDSHAKE_DONE) {
/* SSL library may have more bytes ready to read then we ask to read.
* Therefore, read in a loop until we read everything. Without the loop,
* we skip to the next select() cycle which can just timeout. */
while ((n = SSL_read(conn->ssl, buf, sizeof(buf))) > 0) {
DBG(("%p %d bytes <- %d (SSL)", conn, n, conn->sock));
mbuf_append(&conn->recv_mbuf, buf, n);
ns_call(conn, NS_RECV, &n);
}
ns_ssl_err(conn, n);
} else {
ns_ssl_begin(conn);
return;
}
} else
#endif
{
while ((n = (int) NS_RECV_FUNC(
conn->sock, buf, recv_avail_size(conn, sizeof(buf)), 0)) > 0) {
DBG(("%p %d bytes (PLAIN) <- %d", conn, n, conn->sock));
mbuf_append(&conn->recv_mbuf, buf, n);
ns_call(conn, NS_RECV, &n);
}
}
if (ns_is_error(n)) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
}
static void ns_handle_udp(struct ns_connection *ls) {
struct ns_connection nc;
char buf[NS_UDP_RECEIVE_BUFFER_SIZE];
int n;
socklen_t s_len = sizeof(nc.sa);
memset(&nc, 0, sizeof(nc));
n = recvfrom(ls->sock, buf, sizeof(buf), 0, &nc.sa.sa, &s_len);
if (n <= 0) {
DBG(("%p recvfrom: %s", ls, strerror(errno)));
} else {
nc.mgr = ls->mgr;
nc.recv_iobuf.buf = buf;
nc.recv_iobuf.len = nc.recv_iobuf.size = n;
nc.sock = ls->sock;
nc.handler = ls->handler;
nc.user_data = ls->user_data;
nc.proto_data = ls->proto_data;
nc.proto_handler = ls->proto_handler;
nc.mgr = ls->mgr;
nc.listener = ls;
nc.flags = NSF_UDP;
DBG(("%p %d bytes received", ls, n));
ns_call(&nc, NS_RECV, &n);
}
}
static void ns_write_to_socket(struct ns_connection *conn) {
struct iobuf *io = &conn->send_iobuf;
int n = 0;
#ifdef NS_ENABLE_SSL
if (conn->ssl != NULL) {
n = SSL_write(conn->ssl, io->buf, io->len);
if (n <= 0) {
int ssl_err = ns_ssl_err(conn, n);
if (ssl_err == SSL_ERROR_WANT_READ || ssl_err == SSL_ERROR_WANT_WRITE) {
return; /* Call us again */
} else {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
}
} else
#endif
{ n = (int) send(conn->sock, io->buf, io->len, 0); }
DBG(("%p %lu -> %d bytes", conn, conn->flags, n));
ns_call(conn, NS_SEND, &n);
if (ns_is_error(n)) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
} else if (n > 0) {
iobuf_remove(io, n);
}
}
static struct ns_connection *accept_conn(struct ns_connection *ls) {
struct ns_connection *c = NULL;
union socket_address sa;
socklen_t len = sizeof(sa);
sock_t sock = INVALID_SOCKET;
/* NOTE(lsm): on Windows, sock is always > FD_SETSIZE */
if ((sock = accept(ls->sock, &sa.sa, &len)) == INVALID_SOCKET) {
} else if ((c = ns_add_sock(ls->mgr, sock, ls->handler)) == NULL) {
closesocket(sock);
#ifdef NS_ENABLE_SSL
} else if (ls->ssl_ctx != NULL &&
((c->ssl = SSL_new(ls->ssl_ctx)) == NULL ||
SSL_set_fd(c->ssl, sock) != 1)) {
DBG(("SSL error"));
ns_close_conn(c);
c = NULL;
#endif
} else {
c->listener = ls;
c->proto_data = ls->proto_data;
c->proto_handler = ls->proto_handler;
c->user_data = ls->user_data;
ns_call(c, NS_ACCEPT, &sa);
DBG(("%p %d %p %p", c, c->sock, c->ssl_ctx, c->ssl));
}
return c;
}
static void ns_handle_udp(struct ns_connection *ls) {
struct ns_connection nc;
char buf[NS_UDP_RECEIVE_BUFFER_SIZE];
int n;
socklen_t s_len = sizeof(nc.sa);
memset(&nc, 0, sizeof(nc));
n = recvfrom(ls->sock, buf, sizeof(buf), 0, &nc.sa.sa, &s_len);
if (n <= 0) {
DBG(("%p recvfrom: %s", ls, strerror(errno)));
} else {
union socket_address sa = nc.sa;
/* Copy all attributes, preserving sender address */
nc = *ls;
/* Then override some */
nc.sa = sa;
nc.recv_mbuf.buf = buf;
nc.recv_mbuf.len = nc.recv_mbuf.size = n;
nc.listener = ls;
nc.flags = NSF_UDP;
/* Call NS_RECV handler */
DBG(("%p %d bytes received", ls, n));
ns_call(&nc, NS_RECV, &n);
/*
* See https://github.com/cesanta/fossa/issues/207
* ns_call migth set flags. They need to be synced back to ls.
*/
ls->flags = nc.flags;
}
}
/*
* Callback for the async resolver on ns_connect_opt() call.
* Main task of this function is to trigger NS_CONNECT event with
* either failure (and dealloc the connection)
* or success (and proceed with connect()
*/
static void resolve_cb(struct ns_dns_message *msg, void *data) {
struct ns_connection *nc = (struct ns_connection *) data;
int i;
int failure = -1;
if (msg != NULL) {
/*
* Take the first DNS A answer and run...
*/
for (i = 0; i < msg->num_answers; i++) {
if (msg->answers[i].rtype == NS_DNS_A_RECORD) {
static struct ns_add_sock_opts opts;
/*
* Async resolver guarantees that there is at least one answer.
* TODO(lsm): handle IPv6 answers too
*/
ns_dns_parse_record_data(msg, &msg->answers[i], &nc->sa.sin.sin_addr,
4);
/* Make ns_finish_connect() trigger NS_CONNECT on failure */
nc->flags |= NSF_CONNECTING;
ns_finish_connect(nc, nc->flags & NSF_UDP ? SOCK_DGRAM : SOCK_STREAM,
&nc->sa, opts);
return;
}
}
}
/*
* If we get there was no NS_DNS_A_RECORD in the answer
*/
ns_call(nc, NS_CONNECT, &failure);
ns_destroy_conn(nc);
}
static void ns_close_conn(struct ns_connection *conn) {
DBG(("%p %lu", conn, conn->flags));
if (!(conn->flags & NSF_CONNECTING)) {
ns_call(conn, NS_CLOSE, NULL);
}
ns_remove_conn(conn);
ns_destroy_conn(conn);
}
/*
* Schedules an async connect for a resolved address and proto.
* Called from two places: `ns_connect_opt()` and from async resolver.
* When called from the async resolver, it must trigger `NS_CONNECT` event
* with a failure flag to indicate connection failure.
*/
NS_INTERNAL struct ns_connection *ns_finish_connect(struct ns_connection *nc,
int proto,
union socket_address *sa,
struct ns_add_sock_opts o) {
sock_t sock = INVALID_SOCKET;
int rc;
DBG(("%p %s://%s:%hu", nc, proto == SOCK_DGRAM ? "udp" : "tcp",
inet_ntoa(nc->sa.sin.sin_addr), ntohs(nc->sa.sin.sin_port)));
if ((sock = socket(AF_INET, proto, 0)) == INVALID_SOCKET) {
int failure = errno;
NS_SET_PTRPTR(o.error_string, "cannot create socket");
if (nc->flags & NSF_CONNECTING) {
ns_call(nc, NS_CONNECT, &failure);
}
ns_destroy_conn(nc);
return NULL;
}
ns_set_non_blocking_mode(sock);
rc = (proto == SOCK_DGRAM) ? 0 : connect(sock, &sa->sa, sizeof(sa->sin));
if (rc != 0 && ns_is_error(rc)) {
NS_SET_PTRPTR(o.error_string, "cannot connect to socket");
if (nc->flags & NSF_CONNECTING) {
ns_call(nc, NS_CONNECT, &rc);
}
ns_destroy_conn(nc);
close(sock);
return NULL;
}
/* Fire NS_CONNECT on next poll. */
nc->flags |= NSF_CONNECTING;
/* No ns_destroy_conn() call after this! */
ns_set_sock(nc, sock);
return nc;
}
static void ns_write_to_socket(struct ns_connection *conn) {
struct mbuf *io = &conn->send_mbuf;
int n = 0;
assert(io->len > 0);
#ifdef NS_ENABLE_SSL
if (conn->ssl != NULL) {
if (conn->flags & NSF_SSL_HANDSHAKE_DONE) {
n = SSL_write(conn->ssl, io->buf, io->len);
if (n <= 0) {
int ssl_err = ns_ssl_err(conn, n);
if (ssl_err == SSL_ERROR_WANT_READ || ssl_err == SSL_ERROR_WANT_WRITE) {
return; /* Call us again */
} else {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
} else {
/* Successful SSL operation, clear off SSL wait flags */
conn->flags &= ~(NSF_WANT_READ | NSF_WANT_WRITE);
}
} else {
ns_ssl_begin(conn);
return;
}
} else
#endif
{
n = (int) NS_SEND_FUNC(conn->sock, io->buf, io->len, 0);
}
DBG(("%p %d bytes -> %d", conn, n, conn->sock));
if (ns_is_error(n)) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
} else if (n > 0) {
#ifndef NS_DISABLE_FILESYSTEM
/* LCOV_EXCL_START */
if (conn->mgr->hexdump_file != NULL) {
ns_hexdump_connection(conn, conn->mgr->hexdump_file, n, NS_SEND);
}
/* LCOV_EXCL_STOP */
#endif
mbuf_remove(io, n);
}
ns_call(conn, NS_SEND, &n);
}
static void ns_mgr_handle_connection(struct ns_connection *nc, int fd_flags,
time_t now) {
DBG(("%p fd=%d fd_flags=%d nc_flags=%lu rmbl=%d smbl=%d", nc, nc->sock,
fd_flags, nc->flags, (int) nc->recv_mbuf.len, (int) nc->send_mbuf.len));
if (fd_flags != 0) nc->last_io_time = now;
if (nc->flags & NSF_CONNECTING) {
if (fd_flags != 0) {
ns_read_from_socket(nc);
}
return;
}
if (nc->flags & NSF_LISTENING) {
/*
* We're not looping here, and accepting just one connection at
* a time. The reason is that eCos does not respect non-blocking
* flag on a listening socket and hangs in a loop.
*/
if (fd_flags & _NSF_FD_CAN_READ) accept_conn(nc);
return;
}
if (fd_flags & _NSF_FD_CAN_READ) {
if (nc->flags & NSF_UDP) {
ns_handle_udp(nc);
} else {
ns_read_from_socket(nc);
}
if (nc->flags & NSF_CLOSE_IMMEDIATELY) return;
}
if ((fd_flags & _NSF_FD_CAN_WRITE) && !(nc->flags & NSF_DONT_SEND) &&
!(nc->flags & NSF_UDP)) { /* Writes to UDP sockets are not buffered. */
ns_write_to_socket(nc);
}
if (!(fd_flags & (_NSF_FD_CAN_READ | _NSF_FD_CAN_WRITE))) {
ns_call(nc, NS_POLL, &now);
}
DBG(("%p after fd=%d nc_flags=%lu rmbl=%d smbl=%d", nc, nc->sock, nc->flags,
(int) nc->recv_mbuf.len, (int) nc->send_mbuf.len));
}
static void ns_ssl_begin(struct ns_connection *nc) {
int server_side = nc->listener != NULL;
int res = server_side ? SSL_accept(nc->ssl) : SSL_connect(nc->ssl);
if (res == 1) {
nc->flags |= NSF_SSL_HANDSHAKE_DONE;
nc->flags &= ~(NSF_WANT_READ | NSF_WANT_WRITE);
if (server_side) {
union socket_address sa;
socklen_t sa_len = sizeof(sa);
/* In case port was set to 0, get the real port number */
(void) getsockname(nc->sock, &sa.sa, &sa_len);
ns_call(nc, NS_ACCEPT, &sa);
}
} else {
int ssl_err = ns_ssl_err(nc, res);
if (ssl_err != SSL_ERROR_WANT_READ && ssl_err != SSL_ERROR_WANT_WRITE) {
nc->flags |= NSF_CLOSE_IMMEDIATELY;
}
}
}
/*
* This function performs the actual IO, and must be called in a loop
* (an event loop). Returns the current timestamp.
*/
time_t ns_mgr_poll(struct ns_mgr *mgr, int milli) {
struct ns_connection *nc, *tmp;
struct timeval tv;
fd_set read_set, write_set, err_set;
sock_t max_fd = INVALID_SOCKET;
time_t current_time = time(NULL);
FD_ZERO(&read_set);
FD_ZERO(&write_set);
FD_ZERO(&err_set);
ns_add_to_set(mgr->ctl[1], &read_set, &max_fd);
for (nc = mgr->active_connections; nc != NULL; nc = tmp) {
tmp = nc->next;
if (!(nc->flags & (NSF_LISTENING | NSF_CONNECTING))) {
ns_call(nc, NS_POLL, ¤t_time);
}
/*
* NS_POLL handler could have signaled us to close the connection
* by setting NSF_CLOSE_IMMEDIATELY flag. In this case, we don't want to
* trigger any other events on that connection, but close it right away.
*/
if (nc->flags & NSF_CLOSE_IMMEDIATELY) {
/* NOTE(lsm): this call removes nc from the mgr->active_connections */
ns_close_conn(nc);
continue;
}
if (!(nc->flags & NSF_WANT_WRITE)) {
/*DBG(("%p read_set", nc)); */
ns_add_to_set(nc->sock, &read_set, &max_fd);
}
if (((nc->flags & NSF_CONNECTING) && !(nc->flags & NSF_WANT_READ)) ||
(nc->send_iobuf.len > 0 && !(nc->flags & NSF_CONNECTING) &&
!(nc->flags & NSF_BUFFER_BUT_DONT_SEND))) {
/*DBG(("%p write_set", nc)); */
ns_add_to_set(nc->sock, &write_set, &max_fd);
ns_add_to_set(nc->sock, &err_set, &max_fd);
}
}
tv.tv_sec = milli / 1000;
tv.tv_usec = (milli % 1000) * 1000;
if (select((int) max_fd + 1, &read_set, &write_set, &err_set, &tv) > 0) {
/* select() might have been waiting for a long time, reset current_time
* now to prevent last_io_time being set to the past. */
current_time = time(NULL);
/* Read wakeup messages */
if (mgr->ctl[1] != INVALID_SOCKET &&
FD_ISSET(mgr->ctl[1], &read_set)) {
struct ctl_msg ctl_msg;
int len = (int) recv(mgr->ctl[1], (char *) &ctl_msg, sizeof(ctl_msg), 0);
send(mgr->ctl[1], ctl_msg.message, 1, 0);
if (len >= (int) sizeof(ctl_msg.callback) && ctl_msg.callback != NULL) {
struct ns_connection *c;
for (c = ns_next(mgr, NULL); c != NULL; c = ns_next(mgr, c)) {
ctl_msg.callback(c, NS_POLL, ctl_msg.message);
}
}
}
for (nc = mgr->active_connections; nc != NULL; nc = tmp) {
tmp = nc->next;
/* Windows reports failed connect() requests in err_set */
if (FD_ISSET(nc->sock, &err_set) && (nc->flags & NSF_CONNECTING)) {
nc->last_io_time = current_time;
ns_read_from_socket(nc);
}
if (FD_ISSET(nc->sock, &read_set)) {
nc->last_io_time = current_time;
if (nc->flags & NSF_LISTENING) {
if (nc->flags & NSF_UDP) {
ns_handle_udp(nc);
} else {
/* We're not looping here, and accepting just one connection at
* a time. The reason is that eCos does not respect non-blocking
* flag on a listening socket and hangs in a loop. */
accept_conn(nc);
}
} else {
ns_read_from_socket(nc);
}
}
if (FD_ISSET(nc->sock, &write_set)) {
nc->last_io_time = current_time;
if (nc->flags & NSF_CONNECTING) {
ns_read_from_socket(nc);
} else if (!(nc->flags & NSF_BUFFER_BUT_DONT_SEND) &&
!(nc->flags & NSF_CLOSE_IMMEDIATELY)) {
ns_write_to_socket(nc);
}
}
}
}
for (nc = mgr->active_connections; nc != NULL; nc = tmp) {
tmp = nc->next;
if ((nc->flags & NSF_CLOSE_IMMEDIATELY) ||
(nc->send_iobuf.len == 0 &&
(nc->flags & NSF_FINISHED_SENDING_DATA))) {
ns_close_conn(nc);
}
}
return current_time;
}
static void ns_read_from_socket(struct ns_connection *conn) {
char buf[NS_READ_BUFFER_SIZE];
int n = 0;
if (conn->flags & NSF_CONNECTING) {
int ok = 1, ret;
socklen_t len = sizeof(ok);
ret = getsockopt(conn->sock, SOL_SOCKET, SO_ERROR, (char *) &ok, &len);
#ifdef NS_ENABLE_SSL
if (ret == 0 && ok == 0 && conn->ssl != NULL) {
int res = SSL_connect(conn->ssl);
int ssl_err = ns_ssl_err(conn, res);
if (res == 1) {
conn->flags |= NSF_SSL_HANDSHAKE_DONE;
} else if (ssl_err == SSL_ERROR_WANT_READ ||
ssl_err == SSL_ERROR_WANT_WRITE) {
return; /* Call us again */
} else {
ok = 1;
}
}
#endif
conn->flags &= ~NSF_CONNECTING;
DBG(("%p ok=%d", conn, ok));
if (ok != 0) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
ns_call(conn, NS_CONNECT, &ok);
return;
}
#ifdef NS_ENABLE_SSL
if (conn->ssl != NULL) {
if (conn->flags & NSF_SSL_HANDSHAKE_DONE) {
/* SSL library may have more bytes ready to read then we ask to read.
* Therefore, read in a loop until we read everything. Without the loop,
* we skip to the next select() cycle which can just timeout. */
while ((n = SSL_read(conn->ssl, buf, sizeof(buf))) > 0) {
DBG(("%p %lu <- %d bytes (SSL)", conn, conn->flags, n));
iobuf_append(&conn->recv_iobuf, buf, n);
ns_call(conn, NS_RECV, &n);
}
ns_ssl_err(conn, n);
} else {
int res = SSL_accept(conn->ssl);
int ssl_err = ns_ssl_err(conn, res);
if (res == 1) {
conn->flags |= NSF_SSL_HANDSHAKE_DONE;
} else if (ssl_err == SSL_ERROR_WANT_READ ||
ssl_err == SSL_ERROR_WANT_WRITE) {
return; /* Call us again */
} else {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
return;
}
} else
#endif
{
while ((n = (int) recv(conn->sock, buf, sizeof(buf), 0)) > 0) {
DBG(("%p %lu <- %d bytes (PLAIN)", conn, conn->flags, n));
iobuf_append(&conn->recv_iobuf, buf, n);
ns_call(conn, NS_RECV, &n);
}
}
if (ns_is_error(n)) {
conn->flags |= NSF_CLOSE_IMMEDIATELY;
}
}
static void ns_close_conn(struct ns_connection *conn) {
DBG(("%p %lu", conn, conn->flags));
ns_call(conn, NS_CLOSE, NULL);
ns_remove_conn(conn);
ns_destroy_conn(conn);
}
