From 04b1757467bcb4e287dd1c34d5a21f76705340d6 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Jos=C3=A9=20Bollo?= Date: Thu, 21 Apr 2016 12:28:51 +0200 Subject: [PATCH] refactoring websockects low-level MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Change-Id: Id0e2952fb61dba0415698642d9eb907f83e18d5b Signed-off-by: José Bollo --- src/afb-ws.c | 23 +++----- src/websock.c | 186 ++++++++++++++++++++++++++++++++++------------------------ src/websock.h | 19 +++--- 3 files changed, 127 insertions(+), 101 deletions(-) diff --git a/src/afb-ws.c b/src/afb-ws.c index 49a314a6..66d1e8d1 100644 --- a/src/afb-ws.c +++ b/src/afb-ws.c @@ -31,7 +31,6 @@ static ssize_t aws_writev(struct afb_ws *ws, const struct iovec *iov, int iovcnt); static ssize_t aws_readv(struct afb_ws *ws, const struct iovec *iov, int iovcnt); -static void aws_disconnect(struct afb_ws *ws); static void aws_on_close(struct afb_ws *ws, uint16_t code, size_t size); static void aws_on_text(struct afb_ws *ws, int last, size_t size); static void aws_on_binary(struct afb_ws *ws, int last, size_t size); @@ -42,7 +41,6 @@ static void aws_on_hangup(struct afb_ws *ws); static struct websock_itf aws_itf = { .writev = (void*)aws_writev, .readv = (void*)aws_readv, - .disconnect = (void*)aws_disconnect, .on_ping = NULL, .on_pong = NULL, @@ -122,17 +120,17 @@ void afb_ws_disconnect(struct afb_ws *ws) void afb_ws_close(struct afb_ws *ws, uint16_t code) { - websock_close_code(ws->ws, code); + websock_close_code(ws->ws, code, NULL, 0); } void afb_ws_text(struct afb_ws *ws, const char *text, size_t length) { - websock_text(ws->ws, text, length); + websock_text(ws->ws, 1, text, length); } void afb_ws_binary(struct afb_ws *ws, const void *data, size_t length) { - websock_binary(ws->ws, data, length); + websock_binary(ws->ws, 1, data, length); } static ssize_t aws_writev(struct afb_ws *ws, const struct iovec *iov, int iovcnt) @@ -163,11 +161,6 @@ static void aws_on_hangup(struct afb_ws *ws) afb_ws_disconnect(ws); } -static void aws_disconnect(struct afb_ws *ws) -{ - afb_ws_disconnect(ws); -} - static inline struct buf aws_pick_buffer(struct afb_ws *ws) { struct buf result = ws->buffer; @@ -212,10 +205,10 @@ static void aws_on_text(struct afb_ws *ws, int last, size_t size) { if (ws->type != none) { websock_drop(ws->ws); - websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR); + websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR, NULL, 0); } else if (ws->itf->on_text == NULL) { websock_drop(ws->ws); - websock_close_code(ws->ws, WEBSOCKET_CODE_CANT_ACCEPT); + websock_close_code(ws->ws, WEBSOCKET_CODE_CANT_ACCEPT, NULL, 0); } else { ws->type = text; aws_on_continue(ws, last, size); @@ -226,10 +219,10 @@ static void aws_on_binary(struct afb_ws *ws, int last, size_t size) { if (ws->type != none) { websock_drop(ws->ws); - websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR); + websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR, NULL, 0); } else if (ws->itf->on_binary == NULL) { websock_drop(ws->ws); - websock_close_code(ws->ws, WEBSOCKET_CODE_CANT_ACCEPT); + websock_close_code(ws->ws, WEBSOCKET_CODE_CANT_ACCEPT, NULL, 0); } else { ws->type = text; aws_on_continue(ws, last, size); @@ -243,7 +236,7 @@ static void aws_on_continue(struct afb_ws *ws, int last, size_t size) if (ws->type == none) { websock_drop(ws->ws); - websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR); + websock_close_code(ws->ws, WEBSOCKET_CODE_PROTOCOL_ERROR, NULL, 0); } else { if (!aws_read(ws, size)) { aws_on_close(ws, WEBSOCKET_CODE_ABNORMAL, 0); diff --git a/src/websock.c b/src/websock.c index c578eba4..945ccd9d 100644 --- a/src/websock.c +++ b/src/websock.c @@ -40,7 +40,10 @@ #define FRAME_GET_PAYLOAD_LEN(BYTE) ( (BYTE) & 0x7F) #define FRAME_SET_FIN(BYTE) (((BYTE) & 0x01) << 7) -#define FRAME_SET_OPCODE(BYTE) ((BYTE) & 0x0F) +#define FRAME_SET_RSV1(BYTE) (((BYTE) & 0x01) << 6) +#define FRAME_SET_RSV2(BYTE) (((BYTE) & 0x01) << 5) +#define FRAME_SET_RSV3(BYTE) (((BYTE) & 0x01) << 4) +#define FRAME_SET_OPCODE(BYTE) ((BYTE) & 0x0F) #define FRAME_SET_MASK(BYTE) (((BYTE) & 0x01) << 7) #define FRAME_SET_LENGTH(X64, IDX) (unsigned char)(((X64) >> ((IDX)*8)) & 0xFF) @@ -55,7 +58,6 @@ #define STATE_START 1 #define STATE_LENGTH 2 #define STATE_DATA 3 -#define STATE_CLOSED 4 struct websock { int state; @@ -96,86 +98,109 @@ static ssize_t ws_read(struct websock *ws, void *buffer, size_t buffer_size) return ws_readv(ws, &iov, 1); } -static ssize_t websock_send(struct websock *ws, unsigned char opcode, - const void *buffer, size_t buffer_size) +static int websock_send_internal(struct websock *ws, unsigned char first, const void *buffer, size_t size) { struct iovec iov[2]; size_t pos; ssize_t rc; unsigned char header[32]; - if (ws->state == STATE_CLOSED) - return 0; - pos = 0; - header[pos++] = (unsigned char)(FRAME_SET_FIN(1) | FRAME_SET_OPCODE(opcode)); - buffer_size = (uint64_t) buffer_size; - if (buffer_size < 126) { - header[pos++] = - FRAME_SET_MASK(0) | FRAME_SET_LENGTH(buffer_size, 0); + header[pos++] = first; + size = (uint64_t) size; + if (size < 126) { + header[pos++] = FRAME_SET_MASK(0) | FRAME_SET_LENGTH(size, 0); } else { - if (buffer_size < 65536) { + if (size < 65536) { header[pos++] = FRAME_SET_MASK(0) | 126; } else { header[pos++] = FRAME_SET_MASK(0) | 127; - header[pos++] = FRAME_SET_LENGTH(buffer_size, 7); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 6); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 5); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 4); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 3); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 2); + header[pos++] = FRAME_SET_LENGTH(size, 7); + header[pos++] = FRAME_SET_LENGTH(size, 6); + header[pos++] = FRAME_SET_LENGTH(size, 5); + header[pos++] = FRAME_SET_LENGTH(size, 4); + header[pos++] = FRAME_SET_LENGTH(size, 3); + header[pos++] = FRAME_SET_LENGTH(size, 2); } - header[pos++] = FRAME_SET_LENGTH(buffer_size, 1); - header[pos++] = FRAME_SET_LENGTH(buffer_size, 0); + header[pos++] = FRAME_SET_LENGTH(size, 1); + header[pos++] = FRAME_SET_LENGTH(size, 0); } iov[0].iov_base = header; iov[0].iov_len = pos; iov[1].iov_base = (void *)buffer; /* const cast */ - iov[1].iov_len = buffer_size; + iov[1].iov_len = size; - rc = ws_writev(ws, iov, 1 + !!buffer_size); + rc = ws_writev(ws, iov, 1 + !!size); - if (opcode == OPCODE_CLOSE) { - ws->length = 0; - ws->state = STATE_CLOSED; - ws->itf->disconnect(ws->closure); - } - return rc; + return rc < 0 ? -1 : 0; } -void websock_close(struct websock *ws) +static inline int websock_send(struct websock *ws, int last, int rsv1, int rsv2, int rsv3, int opcode, const void *buffer, size_t size) { - websock_send(ws, OPCODE_CLOSE, NULL, 0); + unsigned char first = (unsigned char)(FRAME_SET_FIN(last) + | FRAME_SET_RSV1(rsv1) + | FRAME_SET_RSV1(rsv2) + | FRAME_SET_RSV1(rsv3) + | FRAME_SET_OPCODE(opcode)); + return websock_send_internal(ws, first, buffer, size); } -void websock_close_code(struct websock *ws, uint16_t code) +int websock_close(struct websock *ws) { - unsigned char buffer[2]; - /* Send server-side closing handshake */ + return websock_send(ws, 1, 0, 0, 0, OPCODE_CLOSE, NULL, 0); +} + +int websock_close_code(struct websock *ws, uint16_t code, const void *data, size_t length) +{ + unsigned char buffer[125]; + + /* checks the length */ + if (length > 123) { + errno = EINVAL; + return -1; + } + + /* prepare the buffer */ buffer[0] = (unsigned char)((code >> 8) & 0xFF); buffer[1] = (unsigned char)(code & 0xFF); - websock_send(ws, OPCODE_CLOSE, buffer, 2); + if (length != 0) + memcpy(&buffer[2], data, length); + + /* Send server-side closing handshake */ + return websock_send(ws, 1, 0, 0, 0, OPCODE_CLOSE, buffer, 2 + length); } -void websock_ping(struct websock *ws) +int websock_ping(struct websock *ws, const void *data, size_t length) { - websock_send(ws, OPCODE_PING, NULL, 0); + /* checks the length */ + if (length > 125) { + errno = EINVAL; + return -1; + } + + return websock_send(ws, 1, 0, 0, 0, OPCODE_PING, data, length); } -void websock_pong(struct websock *ws) +int websock_pong(struct websock *ws, const void *data, size_t length) { - websock_send(ws, OPCODE_PONG, NULL, 0); + /* checks the length */ + if (length > 125) { + errno = EINVAL; + return -1; + } + + return websock_send(ws, 1, 0, 0, 0, OPCODE_PONG, data, length); } -void websock_text(struct websock *ws, const char *text, size_t length) +int websock_text(struct websock *ws, int last, const char *text, size_t length) { - websock_send(ws, OPCODE_TEXT, text, length); + return websock_send(ws, last, 0, 0, 0, OPCODE_TEXT, text, length); } -void websock_binary(struct websock *ws, const void *data, size_t length) +int websock_binary(struct websock *ws, int last, const void *data, size_t length) { - websock_send(ws, OPCODE_BINARY, data, length); + return websock_send(ws, last, 0, 0, 0, OPCODE_BINARY, data, length); } static int read_header(struct websock *ws) @@ -199,15 +224,16 @@ static int check_control_header(struct websock *ws) return 0; if (FRAME_GET_RSV3(ws->header[0]) != 0) return 0; + if (FRAME_GET_PAYLOAD_LEN(ws->header[1]) > 125) + return 0; if (FRAME_GET_OPCODE(ws->header[0]) == OPCODE_CLOSE) return FRAME_GET_PAYLOAD_LEN(ws->header[1]) != 1; - if (FRAME_GET_MASK(ws->header[1])) - return 0; - return FRAME_GET_PAYLOAD_LEN(ws->header[1]) == 0; + return 1; } int websock_dispatch(struct websock *ws) { + uint16_t code; loop: switch (ws->state) { case STATE_INIT: @@ -234,21 +260,9 @@ loop: ws->szhead += 2; break; case OPCODE_PING: - if (!check_control_header(ws)) - goto protocol_error; - if (ws->itf->on_ping) - ws->itf->on_ping(ws->closure); - else - websock_pong(ws); - ws->state = STATE_INIT; - goto loop; case OPCODE_PONG: if (!check_control_header(ws)) goto protocol_error; - if (ws->itf->on_pong) - ws->itf->on_pong(ws->closure); - ws->state = STATE_INIT; - goto loop; default: break; } @@ -269,7 +283,8 @@ loop: return -1; else if (ws->lenhead < ws->szhead) return 0; - /* compute header values */ + + /* compute length */ switch (FRAME_GET_PAYLOAD_LEN(ws->header[1])) { case 127: ws->length = (((uint64_t) ws->header[2]) << 56) @@ -289,8 +304,12 @@ loop: ws->length = FRAME_GET_PAYLOAD_LEN(ws->header[1]); break; } + if (FRAME_GET_OPCODE(ws->header[0]) == OPCODE_CLOSE && ws->length != 0) + ws->length -= 2; if (ws->length > ws->maxlength) goto too_long_error; + + /* compute mask */ if (FRAME_GET_MASK(ws->header[1])) { ((unsigned char *)&ws->mask)[0] = ws->header[ws->szhead - 4]; ((unsigned char *)&ws->mask)[1] = ws->header[ws->szhead - 3]; @@ -339,16 +358,31 @@ loop: (size_t) ws->length); break; case OPCODE_CLOSE: - ws->state = STATE_CLOSED; - if (ws->length) - ws->itf->on_close(ws->closure, - (uint16_t)((((uint16_t) ws-> header[2]) << 8) | ((uint16_t) ws->header[3])), - (size_t) ws->length); - else - ws->itf->on_close(ws->closure, - WEBSOCKET_CODE_NOT_SET, 0); - ws->itf->disconnect(ws->closure); + if (ws->length == 0) + code = WEBSOCKET_CODE_NOT_SET; + else { + code = (uint16_t)(ws->header[ws->szhead - 2] & 0xff); + code = (uint16_t)(code << 8); + code = (uint16_t)(code | (uint16_t)(ws->header[ws->szhead - 1] & 0xff)); + } + ws->itf->on_close(ws->closure, code, (size_t) ws->length); return 0; + case OPCODE_PING: + if (ws->itf->on_ping) + ws->itf->on_ping(ws->closure, ws->length); + else { + websock_drop(ws); + websock_pong(ws, NULL, 0); + } + ws->state = STATE_INIT; + break; + case OPCODE_PONG: + if (ws->itf->on_pong) + ws->itf->on_pong(ws->closure, ws->length); + else + websock_drop(ws); + ws->state = STATE_INIT; + break; default: goto protocol_error; } @@ -359,18 +393,15 @@ loop: return 0; ws->state = STATE_INIT; break; - - case STATE_CLOSED: - return 0; } goto loop; too_long_error: - websock_close_code(ws, WEBSOCKET_CODE_MESSAGE_TOO_LARGE); + websock_close_code(ws, WEBSOCKET_CODE_MESSAGE_TOO_LARGE, NULL, 0); return 0; protocol_error: - websock_close_code(ws, WEBSOCKET_CODE_PROTOCOL_ERROR); + websock_close_code(ws, WEBSOCKET_CODE_PROTOCOL_ERROR, NULL, 0); return 0; } @@ -380,7 +411,7 @@ ssize_t websock_read(struct websock * ws, void *buffer, size_t size) uint8_t m, *b8; ssize_t rc; - if (ws->state != STATE_DATA && ws->state != STATE_CLOSED) + if (ws->state != STATE_DATA) return 0; if (size > ws->length) @@ -424,11 +455,14 @@ ssize_t websock_read(struct websock * ws, void *buffer, size_t size) return rc; } -void websock_drop(struct websock *ws) +int websock_drop(struct websock *ws) { char buffer[8000]; - while (ws->length && ws_read(ws, buffer, sizeof buffer) >= 0) ; + while (ws->length) + if (ws_read(ws, buffer, sizeof buffer) < 0) + return -1; + return 0; } struct websock *websock_create_v13(const struct websock_itf *itf, void *closure) diff --git a/src/websock.h b/src/websock.h index 7785a0c0..f06bc23d 100644 --- a/src/websock.h +++ b/src/websock.h @@ -40,10 +40,9 @@ struct iovec; struct websock_itf { ssize_t (*writev) (void *, const struct iovec *, int); ssize_t (*readv) (void *, const struct iovec *, int); - void (*disconnect) (void *); - void (*on_ping) (void *); /* if not NULL, responsible of pong */ - void (*on_pong) (void *); + void (*on_ping) (void *, size_t size); /* if not NULL, responsible of pong */ + void (*on_pong) (void *, size_t size); void (*on_close) (void *, uint16_t code, size_t size); void (*on_text) (void *, int last, size_t size); void (*on_binary) (void *, int last, size_t size); @@ -53,16 +52,16 @@ struct websock_itf { struct websock; -void websock_close(struct websock *ws); -void websock_close_code(struct websock *ws, uint16_t code); +int websock_close(struct websock *ws); +int websock_close_code(struct websock *ws, uint16_t code, const void *data, size_t length); -void websock_ping(struct websock *ws); -void websock_pong(struct websock *ws); -void websock_text(struct websock *ws, const char *text, size_t length); -void websock_binary(struct websock *ws, const void *data, size_t length); +int websock_ping(struct websock *ws, const void *data, size_t length); +int websock_pong(struct websock *ws, const void *data, size_t length); +int websock_text(struct websock *ws, int last, const char *text, size_t length); +int websock_binary(struct websock *ws, int last, const void *data, size_t length); ssize_t websock_read(struct websock *ws, void *buffer, size_t size); -void websock_drop(struct websock *ws); +int websock_drop(struct websock *ws); int websock_dispatch(struct websock *ws); -- 2.16.6