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/*
* Copyright (c) 2014-2016 Cesanta Software Limited
* All rights reserved
*/
#if MG_ENABLE_SSL && MG_NET_IF == MG_NET_IF_LWIP_LOW_LEVEL
#include "common/mg_mem.h"
#include "common/cs_dbg.h"
#include <lwip/pbuf.h>
#include <lwip/tcp.h>
#ifndef MG_LWIP_SSL_IO_SIZE
#define MG_LWIP_SSL_IO_SIZE 1024
#endif
#ifndef MIN
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#endif
void mg_lwip_ssl_do_hs(struct mg_connection *nc) {
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) nc->sock;
int server_side = (nc->listener != NULL);
enum mg_ssl_if_result res;
if (nc->flags & MG_F_CLOSE_IMMEDIATELY) return;
res = mg_ssl_if_handshake(nc);
DBG(("%p %lu %d %d", nc, nc->flags, server_side, res));
if (res != MG_SSL_OK) {
if (res == MG_SSL_WANT_WRITE) {
nc->flags |= MG_F_WANT_WRITE;
cs->err = 0;
} else if (res == MG_SSL_WANT_READ) {
/*
* Nothing to do in particular, we are callback-driven.
* What we definitely do not need anymore is SSL reading (nothing left).
*/
nc->flags &= ~MG_F_WANT_READ;
cs->err = 0;
} else {
cs->err = res;
if (server_side) {
mg_lwip_post_signal(MG_SIG_CLOSE_CONN, nc);
} else {
mg_lwip_post_signal(MG_SIG_CONNECT_RESULT, nc);
}
}
} else {
cs->err = 0;
nc->flags &= ~MG_F_WANT_WRITE;
/*
* Handshake is done. Schedule a read immediately to consume app data
* which may already be waiting.
*/
nc->flags |= (MG_F_SSL_HANDSHAKE_DONE | MG_F_WANT_READ);
if (server_side) {
mg_lwip_accept_conn(nc, cs->pcb.tcp);
} else {
mg_lwip_post_signal(MG_SIG_CONNECT_RESULT, nc);
}
}
}
void mg_lwip_ssl_send(struct mg_connection *nc) {
if (nc->sock == INVALID_SOCKET) {
DBG(("%p invalid socket", nc));
return;
}
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) nc->sock;
/* It's ok if the buffer is empty. Return value of 0 may also be valid. */
int len = cs->last_ssl_write_size;
if (len == 0) {
len = MIN(MG_LWIP_SSL_IO_SIZE, nc->send_mbuf.len);
}
int ret = mg_ssl_if_write(nc, nc->send_mbuf.buf, len);
DBG(("%p SSL_write %u = %d", nc, len, ret));
if (ret > 0) {
mg_if_sent_cb(nc, ret);
cs->last_ssl_write_size = 0;
} else if (ret < 0) {
/* This is tricky. We must remember the exact data we were sending to retry
* exactly the same send next time. */
cs->last_ssl_write_size = len;
}
if (ret == len) {
nc->flags &= ~MG_F_WANT_WRITE;
} else if (ret == MG_SSL_WANT_WRITE) {
nc->flags |= MG_F_WANT_WRITE;
} else {
mg_lwip_post_signal(MG_SIG_CLOSE_CONN, nc);
}
}
void mg_lwip_ssl_recv(struct mg_connection *nc) {
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) nc->sock;
/* Don't deliver data before connect callback */
if (nc->flags & MG_F_CONNECTING) return;
while (nc->recv_mbuf.len < nc->recv_mbuf_limit) {
char *buf = (char *) MG_MALLOC(MG_LWIP_SSL_IO_SIZE);
if (buf == NULL) return;
int ret = mg_ssl_if_read(nc, buf, MG_LWIP_SSL_IO_SIZE);
DBG(("%p %p SSL_read %u = %d", nc, cs->rx_chain, MG_LWIP_SSL_IO_SIZE, ret));
if (ret <= 0) {
MG_FREE(buf);
if (ret == MG_SSL_WANT_WRITE) {
nc->flags |= MG_F_WANT_WRITE;
return;
} else if (ret == MG_SSL_WANT_READ) {
/*
* Nothing to do in particular, we are callback-driven.
* What we definitely do not need anymore is SSL reading (nothing left).
*/
nc->flags &= ~MG_F_WANT_READ;
cs->err = 0;
return;
} else {
mg_lwip_post_signal(MG_SIG_CLOSE_CONN, nc);
return;
}
} else {
mg_if_recv_tcp_cb(nc, buf, ret, 1 /* own */);
}
}
}
#ifdef KR_VERSION
ssize_t kr_send(int fd, const void *buf, size_t len) {
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) fd;
int ret = mg_lwip_tcp_write(cs->nc, buf, len);
DBG(("%p mg_lwip_tcp_write %u = %d", cs->nc, len, ret));
if (ret == 0) ret = KR_IO_WOULDBLOCK;
return ret;
}
ssize_t kr_recv(int fd, void *buf, size_t len) {
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) fd;
struct pbuf *seg = cs->rx_chain;
if (seg == NULL) {
DBG(("%u - nothing to read", len));
return KR_IO_WOULDBLOCK;
}
size_t seg_len = (seg->len - cs->rx_offset);
DBG(("%u %u %u %u", len, cs->rx_chain->len, seg_len, cs->rx_chain->tot_len));
len = MIN(len, seg_len);
pbuf_copy_partial(seg, buf, len, cs->rx_offset);
cs->rx_offset += len;
tcp_recved(cs->pcb.tcp, len);
if (cs->rx_offset == cs->rx_chain->len) {
cs->rx_chain = pbuf_dechain(cs->rx_chain);
pbuf_free(seg);
cs->rx_offset = 0;
}
return len;
}
#elif MG_SSL_IF == MG_SSL_IF_MBEDTLS
int ssl_socket_send(void *ctx, const unsigned char *buf, size_t len) {
struct mg_connection *nc = (struct mg_connection *) ctx;
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) nc->sock;
int ret = mg_lwip_tcp_write(cs->nc, buf, len);
if (ret == 0) ret = MBEDTLS_ERR_SSL_WANT_WRITE;
LOG(LL_DEBUG, ("%p %d -> %d", nc, len, ret));
return ret;
}
int ssl_socket_recv(void *ctx, unsigned char *buf, size_t len) {
struct mg_connection *nc = (struct mg_connection *) ctx;
struct mg_lwip_conn_state *cs = (struct mg_lwip_conn_state *) nc->sock;
struct pbuf *seg = cs->rx_chain;
if (seg == NULL) {
DBG(("%u - nothing to read", len));
return MBEDTLS_ERR_SSL_WANT_READ;
}
size_t seg_len = (seg->len - cs->rx_offset);
DBG(("%u %u %u %u", len, cs->rx_chain->len, seg_len, cs->rx_chain->tot_len));
mgos_lock();
len = MIN(len, seg_len);
pbuf_copy_partial(seg, buf, len, cs->rx_offset);
cs->rx_offset += len;
/* TCP PCB may be NULL if connection has already been closed
* but we still have data to deliver to SSL. */
if (cs->pcb.tcp != NULL) tcp_recved(cs->pcb.tcp, len);
if (cs->rx_offset == cs->rx_chain->len) {
cs->rx_chain = pbuf_dechain(cs->rx_chain);
pbuf_free(seg);
cs->rx_offset = 0;
}
mgos_unlock();
LOG(LL_DEBUG, ("%p <- %d", nc, (int) len));
return len;
}
#endif
#endif /* MG_ENABLE_SSL && MG_NET_IF == MG_NET_IF_LWIP_LOW_LEVEL */