/** Send callback function called from mbedtls (set via mbedtls_ssl_set_bio)
* This function is either called during handshake or when sending application
* data via @ref altcp_mbedtls_write (or altcp_write)
*/
static int
altcp_mbedtls_bio_send(void *ctx, const unsigned char *dataptr, size_t size)
{
struct altcp_pcb *conn = (struct altcp_pcb *) ctx;
int written = 0;
size_t size_left = size;
u8_t apiflags = TCP_WRITE_FLAG_COPY;
LWIP_ASSERT("conn != NULL", conn != NULL);
if ((conn == NULL) || (conn->inner_conn == NULL)) {
return MBEDTLS_ERR_NET_INVALID_CONTEXT;
}
while (size_left) {
u16_t write_len = (u16_t)LWIP_MIN(size_left, 0xFFFF);
err_t err = altcp_write(conn->inner_conn, (const void *)dataptr, write_len, apiflags);
if (err == ERR_OK) {
written += write_len;
size_left -= write_len;
} else if (err == ERR_MEM) {
if (written) {
return written;
}
return 0; /* MBEDTLS_ERR_SSL_WANT_WRITE; */
} else {
LWIP_ASSERT("tls_write, tcp_write: err != ERR MEM", 0);
/* @todo: return MBEDTLS_ERR_NET_CONN_RESET or MBEDTLS_ERR_NET_SEND_FAILED */
return MBEDTLS_ERR_NET_SEND_FAILED;
}
}
return written;
}
/** If in state SMTP_BODY, try to send more body data */
static void
smtp_send_body(struct smtp_session *s, struct altcp_pcb *pcb)
{
err_t err;
if (s->state == SMTP_BODY) {
#if SMTP_BODYDH
if (s->bodydh) {
smtp_send_body_data_handler(s, pcb);
} else
#endif /* SMTP_BODYDH */
{
u16_t send_len = (u16_t)(s->body_len - s->body_sent);
if (send_len > 0) {
u16_t snd_buf = altcp_sndbuf(pcb);
if (send_len > snd_buf) {
send_len = snd_buf;
}
if (send_len > 0) {
/* try to send something out */
err = altcp_write(pcb, &s->body[s->body_sent], (u16_t)send_len, TCP_WRITE_FLAG_COPY);
if (err == ERR_OK) {
s->timer = SMTP_TIMEOUT_DATABLOCK;
s->body_sent = (u16_t)(s->body_sent + send_len);
if (s->body_sent < s->body_len) {
LWIP_DEBUGF(SMTP_DEBUG_STATE, ("smtp_send_body: %d of %d bytes written\n",
s->body_sent, s->body_len));
}
}
}
}
}
if (s->body_sent == s->body_len) {
/* the whole body has been written, write last line */
LWIP_DEBUGF(SMTP_DEBUG_STATE, ("smtp_send_body: body completely written (%d bytes), appending end-of-body\n",
s->body_len));
err = altcp_write(pcb, SMTP_CMD_BODY_FINISHED, SMTP_CMD_BODY_FINISHED_LEN, 0);
if (err == ERR_OK) {
s->timer = SMTP_TIMEOUT_DATATERM;
LWIP_DEBUGF(SMTP_DEBUG_STATE, ("smtp_send_body: end-of-body written, changing state to %s\n",
smtp_state_str[SMTP_QUIT]));
/* last line written, change state, wait for confirmation */
s->state = SMTP_QUIT;
}
}
}
}
err_t
altcp_default_write(struct altcp_pcb *conn, const void *dataptr, u16_t len, u8_t apiflags)
{
if (conn && conn->inner_conn) {
return altcp_write(conn->inner_conn, dataptr, len, apiflags);
}
return ERR_VAL;
}
/**
* Try send as many bytes as possible from output ring buffer
* @param rb Output ring buffer
* @param tpcb TCP connection handle
*/
static void
mqtt_output_send(struct mqtt_ringbuf_t *rb, struct altcp_pcb *tpcb)
{
err_t err;
u8_t wrap = 0;
u16_t ringbuf_lin_len = mqtt_ringbuf_linear_read_length(rb);
u16_t send_len = altcp_sndbuf(tpcb);
LWIP_ASSERT("mqtt_output_send: tpcb != NULL", tpcb != NULL);
if (send_len == 0 || ringbuf_lin_len == 0) {
return;
}
LWIP_DEBUGF(MQTT_DEBUG_TRACE, ("mqtt_output_send: tcp_sndbuf: %d bytes, ringbuf_linear_available: %d, get %d, put %d\n",
send_len, ringbuf_lin_len, rb->get, rb->put));
if (send_len > ringbuf_lin_len) {
/* Space in TCP output buffer is larger than available in ring buffer linear portion */
send_len = ringbuf_lin_len;
/* Wrap around if more data in ring buffer after linear portion */
wrap = (mqtt_ringbuf_len(rb) > ringbuf_lin_len);
}
err = altcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY | (wrap ? TCP_WRITE_FLAG_MORE : 0));
if ((err == ERR_OK) && wrap) {
mqtt_ringbuf_advance_get_idx(rb, send_len);
/* Use the lesser one of ring buffer linear length and TCP send buffer size */
send_len = LWIP_MIN(altcp_sndbuf(tpcb), mqtt_ringbuf_linear_read_length(rb));
err = altcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY);
}
if (err == ERR_OK) {
mqtt_ringbuf_advance_get_idx(rb, send_len);
/* Flush */
altcp_output(tpcb);
} else {
LWIP_DEBUGF(MQTT_DEBUG_WARN, ("mqtt_output_send: Send failed with err %d (\"%s\")\n", err, lwip_strerr(err)));
}
}
/** Elementary sub-function to send data
*
* @returns: BDHALLDATASENT all data has been written
* BDHSOMEDATASENT some data has been written
* 0 no data has been written
*/
static int
smtp_send_bodyh_data(struct altcp_pcb *pcb, const char **from, u16_t *howmany)
{
err_t err;
u16_t len = *howmany;
len = (u16_t)LWIP_MIN(len, altcp_sndbuf(pcb));
err = altcp_write(pcb, *from, len, TCP_WRITE_FLAG_COPY);
if (err == ERR_OK) {
*from += len;
if ((*howmany -= len) > 0) {
return BDHSOMEDATASENT;
}
return BDHALLDATASENT;
}
return 0;
}
/** http client tcp connected callback */
static err_t
httpc_tcp_connected(void *arg, struct altcp_pcb *pcb, err_t err)
{
err_t r;
httpc_state_t* req = (httpc_state_t*)arg;
LWIP_UNUSED_ARG(pcb);
LWIP_UNUSED_ARG(err);
/* send request; last char is zero termination */
r = altcp_write(req->pcb, req->request->payload, req->request->len - 1, TCP_WRITE_FLAG_COPY);
if (r != ERR_OK) {
/* could not write the single small request -> fail, don't retry */
return httpc_close(req, HTTPC_RESULT_ERR_MEM, 0, r);
}
/* everything written, we can free the request */
pbuf_free(req->request);
req->request = NULL;
altcp_output(req->pcb);
return ERR_OK;
}
/** State machine-like implementation of an SMTP client.
*/
static void
smtp_process(void *arg, struct altcp_pcb *pcb, struct pbuf *p)
{
struct smtp_session* s = (struct smtp_session*)arg;
u16_t response_code = 0;
u16_t tx_buf_len = 0;
enum smtp_session_state next_state;
if (arg == NULL) {
/* already closed SMTP connection */
if (p != NULL) {
LWIP_DEBUGF(SMTP_DEBUG_TRACE, ("Received %d bytes after closing: %s\n",
p->tot_len, smtp_pbuf_str(p)));
pbuf_free(p);
}
return;
}
next_state = s->state;
if (p != NULL) {
/* received data */
if (s->p == NULL) {
s->p = p;
} else {
pbuf_cat(s->p, p);
}
} else {
/* idle timer, close connection if timed out */
if (s->timer == 0) {
LWIP_DEBUGF(SMTP_DEBUG_WARN_STATE, ("smtp_process: connection timed out, closing\n"));
smtp_close(s, pcb, SMTP_RESULT_ERR_TIMEOUT, 0, ERR_TIMEOUT);
return;
}
if (s->state == SMTP_BODY) {
smtp_send_body(s, pcb);
return;
}
}
response_code = smtp_is_response(s);
if (response_code) {
LWIP_DEBUGF(SMTP_DEBUG_TRACE, ("smtp_process: received response code: %d\n", response_code));
if (smtp_is_response_finished(s) != ERR_OK) {
LWIP_DEBUGF(SMTP_DEBUG_TRACE, ("smtp_process: partly received response code: %d\n", response_code));
/* wait for next packet to complete the respone */
return;
}
} else {
if (s->p != NULL) {
LWIP_DEBUGF(SMTP_DEBUG_WARN, ("smtp_process: unknown data received (%s)\n",
smtp_pbuf_str(s->p)));
pbuf_free(s->p);
s->p = NULL;
}
return;
}
switch(s->state)
{
case(SMTP_NULL):
/* wait for 220 */
if (response_code == 220) {
/* then send EHLO */
next_state = smtp_prepare_helo(s, &tx_buf_len, pcb);
}
break;
case(SMTP_HELO):
/* wait for 250 */
if (response_code == 250) {
#if SMTP_SUPPORT_AUTH_PLAIN || SMTP_SUPPORT_AUTH_LOGIN
/* then send AUTH or MAIL */
next_state = smtp_prepare_auth_or_mail(s, &tx_buf_len);
}
break;
case(SMTP_AUTH_LOGIN):
case(SMTP_AUTH_PLAIN):
/* wait for 235 */
if (response_code == 235) {
#endif /* SMTP_SUPPORT_AUTH_PLAIN || SMTP_SUPPORT_AUTH_LOGIN */
/* send MAIL */
next_state = smtp_prepare_mail(s, &tx_buf_len);
}
break;
#if SMTP_SUPPORT_AUTH_LOGIN
case(SMTP_AUTH_LOGIN_UNAME):
/* wait for 334 Username */
if (response_code == 334) {
if (pbuf_strstr(s->p, SMTP_RESP_LOGIN_UNAME) != 0xFFFF) {
/* send username */
next_state = smtp_prepare_auth_login_uname(s, &tx_buf_len);
}
}
break;
case(SMTP_AUTH_LOGIN_PASS):
/* wait for 334 Password */
if (response_code == 334) {
if (pbuf_strstr(s->p, SMTP_RESP_LOGIN_PASS) != 0xFFFF) {
/* send username */
next_state = smtp_prepare_auth_login_pass(s, &tx_buf_len);
}
}
break;
#endif /* SMTP_SUPPORT_AUTH_LOGIN */
case(SMTP_MAIL):
/* wait for 250 */
if (response_code == 250) {
/* send RCPT */
next_state = smtp_prepare_rcpt(s, &tx_buf_len);
}
break;
case(SMTP_RCPT):
/* wait for 250 */
if (response_code == 250) {
/* send DATA */
SMEMCPY(s->tx_buf, SMTP_CMD_DATA, SMTP_CMD_DATA_LEN);
tx_buf_len = SMTP_CMD_DATA_LEN;
next_state = SMTP_DATA;
}
break;
case(SMTP_DATA):
/* wait for 354 */
if (response_code == 354) {
/* send email header */
next_state = smtp_prepare_header(s, &tx_buf_len);
}
break;
case(SMTP_BODY):
/* nothing to be done here, handled somewhere else */
break;
case(SMTP_QUIT):
/* wait for 250 */
if (response_code == 250) {
/* send QUIT */
next_state = smtp_prepare_quit(s, &tx_buf_len);
}
break;
case(SMTP_CLOSED):
/* nothing to do, wait for connection closed from server */
return;
default:
LWIP_DEBUGF(SMTP_DEBUG_SERIOUS, ("Invalid state: %d/%s\n", (int)s->state,
smtp_state_str[s->state]));
break;
}
if (s->state == next_state) {
LWIP_DEBUGF(SMTP_DEBUG_WARN_STATE, ("smtp_process[%s]: unexpected response_code, closing: %d (%s)\n",
smtp_state_str[s->state], response_code, smtp_pbuf_str(s->p)));
/* close connection */
smtp_close(s, pcb, SMTP_RESULT_ERR_SVR_RESP, response_code, ERR_OK);
return;
}
if (tx_buf_len > 0) {
SMTP_TX_BUF_MAX(tx_buf_len);
if (altcp_write(pcb, s->tx_buf, tx_buf_len, TCP_WRITE_FLAG_COPY) == ERR_OK) {
LWIP_DEBUGF(SMTP_DEBUG_TRACE, ("smtp_process[%s]: received command %d (%s)\n",
smtp_state_str[s->state], response_code, smtp_pbuf_str(s->p)));
LWIP_DEBUGF(SMTP_DEBUG_TRACE, ("smtp_process[%s]: sent %"U16_F" bytes: \"%s\"\n",
smtp_state_str[s->state], tx_buf_len, s->tx_buf));
s->timer = SMTP_TIMEOUT;
pbuf_free(s->p);
s->p = NULL;
LWIP_DEBUGF(SMTP_DEBUG_STATE, ("smtp_process: changing state from %s to %s\n",
smtp_state_str[s->state], smtp_state_str[next_state]));
s->state = next_state;
if (next_state == SMTP_BODY) {
/* try to stream-send body data right now */
smtp_send_body(s, pcb);
} else if (next_state == SMTP_CLOSED) {
/* sent out all data, delete structure */
altcp_arg(pcb, NULL);
smtp_free(s, SMTP_RESULT_OK, 0, ERR_OK);
}
}
}
}