introduce-04-control-frames.patch
Signed-off-by: Andy Green <andy@warmcat.com>
diff --git a/lib/handshake.c b/lib/handshake.c
index 5dfdc1d..3f5704f 100644
--- a/lib/handshake.c
+++ b/lib/handshake.c
@@ -72,7 +72,7 @@
static int
-handshake_76(struct libwebsocket *wsi)
+handshake_00(struct libwebsocket *wsi)
{
unsigned long key1, key2;
unsigned char sum[16];
@@ -80,7 +80,7 @@
char *p;
int n;
- /* Websocket 76? - confirm we have all the necessary pieces */
+ /* Confirm we have all the necessary pieces */
if (!wsi->utf8_token[WSI_TOKEN_ORIGIN].token_len ||
!wsi->utf8_token[WSI_TOKEN_HOST].token_len ||
@@ -391,6 +391,7 @@
free(response);
wsi->state = WSI_STATE_ESTABLISHED;
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
+ wsi->rx_packet_length = 0;
/* notify user code that we're ready to roll */
@@ -514,14 +515,15 @@
wsi->ietf_spec_revision =
atoi(wsi->utf8_token[WSI_TOKEN_VERSION].token);
+
/*
- * Websocket 04+?
- * confirm we have all the necessary pieces
+ * Perform the handshake according to the protocol version the
+ * client announced
*/
switch (wsi->ietf_spec_revision) {
case 0: /* applies to 76 and 00 */
- if (handshake_76(wsi))
+ if (handshake_00(wsi))
goto bail;
break;
case 4: /* 04 */
diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index fe82856..af37413 100644
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -34,7 +34,13 @@
enum libwebsocket_write_protocol {
LWS_WRITE_TEXT,
LWS_WRITE_BINARY,
- LWS_WRITE_HTTP
+ LWS_WRITE_HTTP,
+
+ /* special 04 opcodes */
+
+ LWS_WRITE_CLOSE,
+ LWS_WRITE_PING,
+ LWS_WRITE_PONG
};
struct libwebsocket;
@@ -177,4 +183,7 @@
extern const struct libwebsocket_protocols *
libwebsockets_get_protocol(struct libwebsocket *wsi);
+extern size_t
+libwebsockets_remaining_packet_payload(struct libwebsocket *wsi);
+
#endif
diff --git a/lib/parsers.c b/lib/parsers.c
index dbee05f..a3d2eba 100644
--- a/lib/parsers.c
+++ b/lib/parsers.c
@@ -216,17 +216,16 @@
case 0:
if (c == 0xff)
wsi->lws_rx_parse_state = LWS_RXPS_SEEN_76_FF;
+ if (c == 0) {
+ wsi->lws_rx_parse_state = LWS_RXPS_EAT_UNTIL_76_FF;
+ wsi->rx_user_buffer_head = 0;
+ }
break;
case 4:
wsi->frame_masking_nonce_04[0] = c;
wsi->lws_rx_parse_state = LWS_RXPS_04_MASK_NONCE_1;
break;
}
-
- if (c == 0) {
- wsi->lws_rx_parse_state = LWS_RXPS_EAT_UNTIL_76_FF;
- wsi->rx_user_buffer_head = 0;
- }
break;
case LWS_RXPS_04_MASK_NONCE_1:
wsi->frame_masking_nonce_04[1] = c;
@@ -255,7 +254,7 @@
memcpy(buf + 4, wsi->masking_key_04, 20);
/*
- * wsi->frame_mask_04 is our recirculating 20-byte XOR key
+ * wsi->frame_mask_04 will be our recirculating 20-byte XOR key
* for this frame
*/
@@ -270,6 +269,188 @@
wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_1;
break;
+
+ /*
+ * 04 logical framing from the spec (all this is masked when incoming
+ * and has to be unmasked)
+ *
+ * We ignore the possibility of extension data because we don't
+ * negotiate any extensions at the moment.
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-------+-+-------------+-------------------------------+
+ * |F|R|R|R| opcode|R| Payload len | Extended payload length |
+ * |I|S|S|S| (4) |S| (7) | (16/63) |
+ * |N|V|V|V| |V| | (if payload len==126/127) |
+ * | |1|2|3| |4| | |
+ * +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - +
+ * | Extended payload length continued, if payload len == 127 |
+ * + - - - - - - - - - - - - - - - +-------------------------------+
+ * | | Extension data |
+ * +-------------------------------+ - - - - - - - - - - - - - - - +
+ * : :
+ * +---------------------------------------------------------------+
+ * : Application data :
+ * +---------------------------------------------------------------+
+ *
+ * We pass payload through to userland as soon as we get it, ignoring
+ * FIN. It's up to userland to buffer it up if it wants to see a
+ * whole unfragmented block of the original size (which may be up to
+ * 2^63 long!)
+ */
+
+ case LWS_RXPS_04_FRAME_HDR_1:
+ /*
+ * 04 spec defines the opcode like this: (1, 2, and 3 are
+ * "control frame" opcodes which may not be fragmented or
+ * have size larger than 126)
+ *
+ * frame-opcode =
+ * %x0 ; continuation frame
+ * / %x1 ; connection close
+ * / %x2 ; ping
+ * / %x3 ; pong
+ * / %x4 ; text frame
+ * / %x5 ; binary frame
+ * / %x6-F ; reserved
+ *
+ * FIN (b7)
+ */
+
+ c = unmask(wsi, c);
+
+ if (c & 0x70) {
+ fprintf(stderr, "Frame has extensions set illegally\n");
+ /* kill the connection */
+ return -1;
+ }
+
+ wsi->opcode = c & 0xf;
+ wsi->final = !!((c >> 7) & 1);
+
+ if (wsi->final &&
+ wsi->opcode == LWS_WS_OPCODE_04__CONTINUATION &&
+ wsi->rx_packet_length == 0) {
+ fprintf(stderr,
+ "Frame starts with final continuation\n");
+ /* kill the connection */
+ return -1;
+ }
+
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN:
+ c = unmask(wsi, c);
+
+ if (c & 0x80) {
+ fprintf(stderr, "Frame has extensions set illegally\n");
+ /* kill the connection */
+ return -1;
+ }
+
+ switch (c) {
+ case 126:
+ /* control frames are not allowed to have big lengths */
+ switch (wsi->opcode) {
+ case LWS_WS_OPCODE_04__CLOSE:
+ case LWS_WS_OPCODE_04__PING:
+ case LWS_WS_OPCODE_04__PONG:
+ fprintf(stderr, "Control frame asking for "
+ "extended length is illegal\n");
+ /* kill the connection */
+ return -1;
+ default:
+ break;
+ }
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN16_2;
+ break;
+ case 127:
+ /* control frames are not allowed to have big lengths */
+ switch (wsi->opcode) {
+ case LWS_WS_OPCODE_04__CLOSE:
+ case LWS_WS_OPCODE_04__PING:
+ case LWS_WS_OPCODE_04__PONG:
+ fprintf(stderr, "Control frame asking for "
+ "extended length is illegal\n");
+ /* kill the connection */
+ return -1;
+ default:
+ break;
+ }
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_8;
+ break;
+ default:
+ wsi->rx_packet_length = c;
+ wsi->lws_rx_parse_state =
+ LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
+ break;
+ }
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN16_2:
+ c = unmask(wsi, c);
+
+ wsi->rx_packet_length = c << 8;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN16_1;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN16_1:
+ c = unmask(wsi, c);
+
+ wsi->rx_packet_length |= c;
+ wsi->lws_rx_parse_state =
+ LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_8:
+ c = unmask(wsi, c);
+ if (c & 0x80) {
+ fprintf(stderr, "b63 of length must be zero\n");
+ /* kill the connection */
+ return -1;
+ }
+ wsi->rx_packet_length = ((size_t)c) << 56;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_7;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_7:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 48;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_6;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_6:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 40;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_5;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_5:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 32;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_4;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_4:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 24;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_3;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_3:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 16;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_2;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_2:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c)) << 8;
+ wsi->lws_rx_parse_state = LWS_RXPS_04_FRAME_HDR_LEN64_1;
+ break;
+
+ case LWS_RXPS_04_FRAME_HDR_LEN64_1:
+ wsi->rx_packet_length |= ((size_t)unmask(wsi, c));
+ wsi->lws_rx_parse_state =
+ LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED;
+ break;
+
case LWS_RXPS_EAT_UNTIL_76_FF:
if (c == 0xff) {
wsi->lws_rx_parse_state = LWS_RXPS_NEW;
@@ -307,7 +488,61 @@
case LWS_RXPS_PULLING_76_LENGTH:
break;
+
case LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED:
+ wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING +
+ (wsi->rx_user_buffer_head++)] = unmask(wsi, c);
+ if (--wsi->rx_packet_length == 0) {
+ wsi->lws_rx_parse_state = LWS_RXPS_NEW;
+ goto spill;
+ }
+ if (wsi->rx_user_buffer_head != MAX_USER_RX_BUFFER)
+ break;
+spill:
+ /*
+ * is this frame a control packet we should take care of at this
+ * layer? If so service it and hide it from the user callback
+ */
+
+ switch (wsi->opcode) {
+ case LWS_WS_OPCODE_04__CLOSE:
+ /* parrot the close packet payload back */
+ n = libwebsocket_write(wsi, (unsigned char *)
+ &wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
+ wsi->rx_user_buffer_head, LWS_WRITE_CLOSE);
+ /* close the connection */
+ return -1;
+
+ case LWS_WS_OPCODE_04__PING:
+ /* parrot the ping packet payload back as a pong*/
+ n = libwebsocket_write(wsi, (unsigned char *)
+ &wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
+ wsi->rx_user_buffer_head, LWS_WRITE_PONG);
+ break;
+
+ case LWS_WS_OPCODE_04__PONG:
+ /* keep the statistics... */
+ wsi->pings_vs_pongs--;
+ /* ... then just drop it */
+ wsi->rx_user_buffer_head = 0;
+ return 0;
+
+ default:
+ break;
+ }
+
+ /*
+ * No it's real payload, pass it up to the user callback.
+ * It's nicely buffered with the pre-padding taken care of
+ * so it can be sent straight out again using libwebsocket_write
+ */
+
+ if (wsi->protocol->callback)
+ wsi->protocol->callback(wsi, LWS_CALLBACK_RECEIVE,
+ wsi->user_space,
+ &wsi->rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING],
+ wsi->rx_user_buffer_head);
+ wsi->rx_user_buffer_head = 0;
break;
}
@@ -325,6 +560,7 @@
fprintf(stderr, "%02X ", buf[n]);
fprintf(stderr, "\n");
#endif
+
/* let the rx protocol state machine have as much as it needs */
n = 0;
@@ -363,6 +599,8 @@
* packet while not burdening the user code with any protocol knowledge.
*/
+ /* FIXME FIN bit */
+
int libwebsocket_write(struct libwebsocket *wsi, unsigned char *buf,
size_t len, enum libwebsocket_write_protocol protocol)
{
@@ -382,7 +620,7 @@
switch (wsi->ietf_spec_revision) {
/* chrome likes this as of 30 Oct */
/* Firefox 4.0b6 likes this as of 30 Oct */
- case 76:
+ case 0:
if (protocol == LWS_WRITE_BINARY) {
/* in binary mode we send 7-bit used length blocks */
pre = 1;
@@ -413,31 +651,31 @@
post = 1;
break;
- case 0:
- buf[-9] = 0xff;
-#if defined __LP64__
- buf[-8] = len >> 56;
- buf[-7] = len >> 48;
- buf[-6] = len >> 40;
- buf[-5] = len >> 32;
-#else
- buf[-8] = 0;
- buf[-7] = 0;
- buf[-6] = 0;
- buf[-5] = 0;
-#endif
- buf[-4] = len >> 24;
- buf[-3] = len >> 16;
- buf[-2] = len >> 8;
- buf[-1] = len;
- pre = 9;
- break;
+ case 4:
- /* just an unimplemented spec right now apparently */
- case 3:
- n = 4; /* text */
- if (protocol == LWS_WRITE_BINARY)
- n = 5; /* binary */
+ switch (protocol) {
+ case LWS_WRITE_TEXT:
+ n = LWS_WS_OPCODE_04__TEXT_FRAME;
+ break;
+ case LWS_WRITE_BINARY:
+ n = LWS_WS_OPCODE_04__BINARY_FRAME;
+ break;
+ case LWS_WRITE_CLOSE:
+ n = LWS_WS_OPCODE_04__CLOSE;
+ break;
+ case LWS_WRITE_PING:
+ n = LWS_WS_OPCODE_04__PING;
+ wsi->pings_vs_pongs++;
+ break;
+ case LWS_WRITE_PONG:
+ n = LWS_WS_OPCODE_04__PONG;
+ break;
+ default:
+ fprintf(stderr, "libwebsocket_write: unknown write "
+ "opcode / protocol\n");
+ return -1;
+ }
+
if (len < 126) {
buf[-2] = n;
buf[-1] = len;
@@ -556,3 +794,26 @@
return 0;
}
+
+/**
+ * libwebsockets_remaining_packet_payload() - Bytes to come before "overall"
+ * rx packet is complete
+ * @wsi: Websocket instance (available from user callback)
+ *
+ * This function is intended to be called from the callback if the
+ * user code is interested in "complete packets" from the client.
+ * libwebsockets just passes through payload as it comes and issues a buffer
+ * additionally when it hits a built-in limit. The LWS_CALLBACK_RECEIVE
+ * callback handler can use this API to find out if the buffer it has just
+ * been given is the last piece of a "complete packet" from the client --
+ * when that is the case libwebsockets_remaining_packet_payload() will return
+ * 0.
+ *
+ * Many protocols won't care becuse their packets are always small.
+ */
+
+size_t
+libwebsockets_remaining_packet_payload(struct libwebsocket *wsi)
+{
+ return wsi->rx_packet_length;
+}
diff --git a/lib/private-libwebsockets.h b/lib/private-libwebsockets.h
index 17b7277..3edc57a 100644
--- a/lib/private-libwebsockets.h
+++ b/lib/private-libwebsockets.h
@@ -77,6 +77,15 @@
#define MAX_WEBSOCKET_04_KEY_LEN 128
#define SYSTEM_RANDOM_FILEPATH "/dev/random"
+enum lws_websocket_opcodes_04 {
+ LWS_WS_OPCODE_04__CONTINUATION = 0,
+ LWS_WS_OPCODE_04__CLOSE = 1,
+ LWS_WS_OPCODE_04__PING = 2,
+ LWS_WS_OPCODE_04__PONG = 3,
+ LWS_WS_OPCODE_04__TEXT_FRAME = 4,
+ LWS_WS_OPCODE_04__BINARY_FRAME = 5,
+};
+
enum lws_connection_states {
WSI_STATE_HTTP,
WSI_STATE_HTTP_HEADERS,
@@ -121,6 +130,17 @@
LWS_RXPS_04_MASK_NONCE_3,
LWS_RXPS_04_FRAME_HDR_1,
+ LWS_RXPS_04_FRAME_HDR_LEN,
+ LWS_RXPS_04_FRAME_HDR_LEN16_2,
+ LWS_RXPS_04_FRAME_HDR_LEN16_1,
+ LWS_RXPS_04_FRAME_HDR_LEN64_8,
+ LWS_RXPS_04_FRAME_HDR_LEN64_7,
+ LWS_RXPS_04_FRAME_HDR_LEN64_6,
+ LWS_RXPS_04_FRAME_HDR_LEN64_5,
+ LWS_RXPS_04_FRAME_HDR_LEN64_4,
+ LWS_RXPS_04_FRAME_HDR_LEN64_3,
+ LWS_RXPS_04_FRAME_HDR_LEN64_2,
+ LWS_RXPS_04_FRAME_HDR_LEN64_1,
LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED
};
@@ -159,10 +179,6 @@
enum lws_token_indexes parser_state;
struct lws_tokens utf8_token[WSI_TOKEN_COUNT];
int ietf_spec_revision;
- unsigned char masking_key_04[20];
- unsigned char frame_mask_04[20];
- unsigned char frame_masking_nonce_04[4];
- unsigned char frame_mask_index;
char rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING + MAX_USER_RX_BUFFER +
LWS_SEND_BUFFER_POST_PADDING];
int rx_user_buffer_head;
@@ -170,7 +186,18 @@
int sock;
enum lws_rx_parse_state lws_rx_parse_state;
+
+ /* 04 protocol specific */
+
+ unsigned char masking_key_04[20];
+ unsigned char frame_masking_nonce_04[4];
+ unsigned char frame_mask_04[20];
+ unsigned char frame_mask_index;
size_t rx_packet_length;
+ unsigned char opcode;
+ unsigned char final;
+
+ int pings_vs_pongs;
#ifdef LWS_OPENSSL_SUPPORT
SSL *ssl;
diff --git a/libwebsockets-api-doc.html b/libwebsockets-api-doc.html
index 6562149..068db9c 100644
--- a/libwebsockets-api-doc.html
+++ b/libwebsockets-api-doc.html
@@ -162,6 +162,29 @@
local files down the http link in a single step.
</blockquote>
<hr>
+<h2>libwebsockets_remaining_packet_payload - Bytes to come before "overall" rx packet is complete</h2>
+<i>size_t</i>
+<b>libwebsockets_remaining_packet_payload</b>
+(<i>struct libwebsocket *</i> <b>wsi</b>)
+<h3>Arguments</h3>
+<dl>
+<dt><b>wsi</b>
+<dd>Websocket instance (available from user callback)
+</dl>
+<h3>Description</h3>
+<blockquote>
+This function is intended to be called from the callback if the
+user code is interested in "complete packets" from the client.
+libwebsockets just passes through payload as it comes and issues a buffer
+additionally when it hits a built-in limit. The LWS_CALLBACK_RECEIVE
+callback handler can use this API to find out if the buffer it has just
+been given is the last piece of a "complete packet" from the client --
+when that is the case <b>libwebsockets_remaining_packet_payload</b> will return
+0.
+<p>
+Many protocols won't care becuse their packets are always small.
+</blockquote>
+<hr>
<h2>callback - User server actions</h2>
<i>int</i>
<b>callback</b>