diff options
Diffstat (limited to 'Utilities/cmcurl/lib/ws.c')
| -rw-r--r-- | Utilities/cmcurl/lib/ws.c | 1132 |
1 files changed, 1132 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/ws.c b/Utilities/cmcurl/lib/ws.c new file mode 100644 index 0000000..adde531 --- /dev/null +++ b/Utilities/cmcurl/lib/ws.c @@ -0,0 +1,1132 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at https://curl.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + * SPDX-License-Identifier: curl + * + ***************************************************************************/ +#include "curl_setup.h" +#include <curl/curl.h> + +#ifdef USE_WEBSOCKETS + +#include "urldata.h" +#include "bufq.h" +#include "dynbuf.h" +#include "rand.h" +#include "curl_base64.h" +#include "connect.h" +#include "sendf.h" +#include "multiif.h" +#include "ws.h" +#include "easyif.h" +#include "transfer.h" +#include "nonblock.h" + +/* The last 3 #include files should be in this order */ +#include "curl_printf.h" +#include "curl_memory.h" +#include "memdebug.h" + + +#define WSBIT_FIN 0x80 +#define WSBIT_OPCODE_CONT 0 +#define WSBIT_OPCODE_TEXT (1) +#define WSBIT_OPCODE_BIN (2) +#define WSBIT_OPCODE_CLOSE (8) +#define WSBIT_OPCODE_PING (9) +#define WSBIT_OPCODE_PONG (0xa) +#define WSBIT_OPCODE_MASK (0xf) + +#define WSBIT_MASK 0x80 + +/* buffer dimensioning */ +#define WS_CHUNK_SIZE 65535 +#define WS_CHUNK_COUNT 2 + +struct ws_frame_meta { + char proto_opcode; + int flags; + const char *name; +}; + +static struct ws_frame_meta WS_FRAMES[] = { + { WSBIT_OPCODE_CONT, CURLWS_CONT, "CONT" }, + { WSBIT_OPCODE_TEXT, CURLWS_TEXT, "TEXT" }, + { WSBIT_OPCODE_BIN, CURLWS_BINARY, "BIN" }, + { WSBIT_OPCODE_CLOSE, CURLWS_CLOSE, "CLOSE" }, + { WSBIT_OPCODE_PING, CURLWS_PING, "PING" }, + { WSBIT_OPCODE_PONG, CURLWS_PONG, "PONG" }, +}; + +static const char *ws_frame_name_of_op(unsigned char proto_opcode) +{ + unsigned char opcode = proto_opcode & WSBIT_OPCODE_MASK; + size_t i; + for(i = 0; i < sizeof(WS_FRAMES)/sizeof(WS_FRAMES[0]); ++i) { + if(WS_FRAMES[i].proto_opcode == opcode) + return WS_FRAMES[i].name; + } + return "???"; +} + +static int ws_frame_op2flags(unsigned char proto_opcode) +{ + unsigned char opcode = proto_opcode & WSBIT_OPCODE_MASK; + size_t i; + for(i = 0; i < sizeof(WS_FRAMES)/sizeof(WS_FRAMES[0]); ++i) { + if(WS_FRAMES[i].proto_opcode == opcode) + return WS_FRAMES[i].flags; + } + return 0; +} + +static unsigned char ws_frame_flags2op(int flags) +{ + size_t i; + for(i = 0; i < sizeof(WS_FRAMES)/sizeof(WS_FRAMES[0]); ++i) { + if(WS_FRAMES[i].flags & flags) + return WS_FRAMES[i].proto_opcode; + } + return 0; +} + +static void ws_dec_info(struct ws_decoder *dec, struct Curl_easy *data, + const char *msg) +{ + switch(dec->head_len) { + case 0: + break; + case 1: + infof(data, "WS-DEC: %s [%s%s]", msg, + ws_frame_name_of_op(dec->head[0]), + (dec->head[0] & WSBIT_FIN)? "" : " NON-FINAL"); + break; + default: + if(dec->head_len < dec->head_total) { + infof(data, "WS-DEC: %s [%s%s](%d/%d)", msg, + ws_frame_name_of_op(dec->head[0]), + (dec->head[0] & WSBIT_FIN)? "" : " NON-FINAL", + dec->head_len, dec->head_total); + } + else { + infof(data, "WS-DEC: %s [%s%s payload=%" CURL_FORMAT_CURL_OFF_T + "/%" CURL_FORMAT_CURL_OFF_T "]", + msg, ws_frame_name_of_op(dec->head[0]), + (dec->head[0] & WSBIT_FIN)? "" : " NON-FINAL", + dec->payload_offset, dec->payload_len); + } + break; + } +} + +typedef ssize_t ws_write_payload(const unsigned char *buf, size_t buflen, + int frame_age, int frame_flags, + curl_off_t payload_offset, + curl_off_t payload_len, + void *userp, + CURLcode *err); + + +static void ws_dec_reset(struct ws_decoder *dec) +{ + dec->frame_age = 0; + dec->frame_flags = 0; + dec->payload_offset = 0; + dec->payload_len = 0; + dec->head_len = dec->head_total = 0; + dec->state = WS_DEC_INIT; +} + +static void ws_dec_init(struct ws_decoder *dec) +{ + ws_dec_reset(dec); +} + +static CURLcode ws_dec_read_head(struct ws_decoder *dec, + struct Curl_easy *data, + struct bufq *inraw) +{ + const unsigned char *inbuf; + size_t inlen; + + while(Curl_bufq_peek(inraw, &inbuf, &inlen)) { + if(dec->head_len == 0) { + dec->head[0] = *inbuf; + Curl_bufq_skip(inraw, 1); + + dec->frame_flags = ws_frame_op2flags(dec->head[0]); + if(!dec->frame_flags) { + failf(data, "WS: unknown opcode: %x", dec->head[0]); + ws_dec_reset(dec); + return CURLE_RECV_ERROR; + } + dec->head_len = 1; + /* ws_dec_info(dec, data, "seeing opcode"); */ + continue; + } + else if(dec->head_len == 1) { + dec->head[1] = *inbuf; + Curl_bufq_skip(inraw, 1); + dec->head_len = 2; + + if(dec->head[1] & WSBIT_MASK) { + /* A client MUST close a connection if it detects a masked frame. */ + failf(data, "WS: masked input frame"); + ws_dec_reset(dec); + return CURLE_RECV_ERROR; + } + /* How long is the frame head? */ + if(dec->head[1] == 126) { + dec->head_total = 4; + continue; + } + else if(dec->head[1] == 127) { + dec->head_total = 10; + continue; + } + else { + dec->head_total = 2; + } + } + + if(dec->head_len < dec->head_total) { + dec->head[dec->head_len] = *inbuf; + Curl_bufq_skip(inraw, 1); + ++dec->head_len; + if(dec->head_len < dec->head_total) { + /* ws_dec_info(dec, data, "decoding head"); */ + continue; + } + } + /* got the complete frame head */ + DEBUGASSERT(dec->head_len == dec->head_total); + switch(dec->head_total) { + case 2: + dec->payload_len = dec->head[1]; + break; + case 4: + dec->payload_len = (dec->head[2] << 8) | dec->head[3]; + break; + case 10: + dec->payload_len = ((curl_off_t)dec->head[2] << 56) | + (curl_off_t)dec->head[3] << 48 | + (curl_off_t)dec->head[4] << 40 | + (curl_off_t)dec->head[5] << 32 | + (curl_off_t)dec->head[6] << 24 | + (curl_off_t)dec->head[7] << 16 | + (curl_off_t)dec->head[8] << 8 | + dec->head[9]; + break; + default: + /* this should never happen */ + DEBUGASSERT(0); + failf(data, "WS: unexpected frame header length"); + return CURLE_RECV_ERROR; + } + + dec->frame_age = 0; + dec->payload_offset = 0; + ws_dec_info(dec, data, "decoded"); + return CURLE_OK; + } + return CURLE_AGAIN; +} + +static CURLcode ws_dec_pass_payload(struct ws_decoder *dec, + struct Curl_easy *data, + struct bufq *inraw, + ws_write_payload *write_payload, + void *write_ctx) +{ + const unsigned char *inbuf; + size_t inlen; + ssize_t nwritten; + CURLcode result; + curl_off_t remain = dec->payload_len - dec->payload_offset; + + (void)data; + while(remain && Curl_bufq_peek(inraw, &inbuf, &inlen)) { + if((curl_off_t)inlen > remain) + inlen = (size_t)remain; + nwritten = write_payload(inbuf, inlen, dec->frame_age, dec->frame_flags, + dec->payload_offset, dec->payload_len, + write_ctx, &result); + if(nwritten < 0) + return result; + Curl_bufq_skip(inraw, (size_t)nwritten); + dec->payload_offset += (curl_off_t)nwritten; + remain = dec->payload_len - dec->payload_offset; + /* infof(data, "WS-DEC: passed %zd bytes payload, %" + CURL_FORMAT_CURL_OFF_T " remain", + nwritten, remain); */ + } + + return remain? CURLE_AGAIN : CURLE_OK; +} + +static CURLcode ws_dec_pass(struct ws_decoder *dec, + struct Curl_easy *data, + struct bufq *inraw, + ws_write_payload *write_payload, + void *write_ctx) +{ + CURLcode result; + + if(Curl_bufq_is_empty(inraw)) + return CURLE_AGAIN; + + switch(dec->state) { + case WS_DEC_INIT: + ws_dec_reset(dec); + dec->state = WS_DEC_HEAD; + /* FALLTHROUGH */ + case WS_DEC_HEAD: + result = ws_dec_read_head(dec, data, inraw); + if(result) { + if(result != CURLE_AGAIN) { + infof(data, "WS: decode error %d", (int)result); + break; /* real error */ + } + /* incomplete ws frame head */ + DEBUGASSERT(Curl_bufq_is_empty(inraw)); + break; + } + /* head parsing done */ + dec->state = WS_DEC_PAYLOAD; + if(dec->payload_len == 0) { + ssize_t nwritten; + const unsigned char tmp = '\0'; + /* special case of a 0 length frame, need to write once */ + nwritten = write_payload(&tmp, 0, dec->frame_age, dec->frame_flags, + 0, 0, write_ctx, &result); + if(nwritten < 0) + return result; + dec->state = WS_DEC_INIT; + break; + } + /* FALLTHROUGH */ + case WS_DEC_PAYLOAD: + result = ws_dec_pass_payload(dec, data, inraw, write_payload, write_ctx); + ws_dec_info(dec, data, "passing"); + if(result) + return result; + /* paylod parsing done */ + dec->state = WS_DEC_INIT; + break; + default: + /* we covered all enums above, but some code analyzers are whimps */ + result = CURLE_FAILED_INIT; + } + return result; +} + +static void update_meta(struct websocket *ws, + int frame_age, int frame_flags, + curl_off_t payload_offset, + curl_off_t payload_len, + size_t cur_len) +{ + ws->frame.age = frame_age; + ws->frame.flags = frame_flags; + ws->frame.offset = payload_offset; + ws->frame.len = cur_len; + ws->frame.bytesleft = (payload_len - payload_offset - cur_len); +} + +static void ws_enc_info(struct ws_encoder *enc, struct Curl_easy *data, + const char *msg) +{ + infof(data, "WS-ENC: %s [%s%s%s payload=%" CURL_FORMAT_CURL_OFF_T + "/%" CURL_FORMAT_CURL_OFF_T "]", + msg, ws_frame_name_of_op(enc->firstbyte), + (enc->firstbyte & WSBIT_OPCODE_MASK) == WSBIT_OPCODE_CONT ? + " CONT" : "", + (enc->firstbyte & WSBIT_FIN)? "" : " NON-FIN", + enc->payload_len - enc->payload_remain, enc->payload_len); +} + +static void ws_enc_reset(struct ws_encoder *enc) +{ + enc->payload_remain = 0; + enc->xori = 0; + enc->contfragment = FALSE; +} + +static void ws_enc_init(struct ws_encoder *enc) +{ + ws_enc_reset(enc); +} + +/*** + RFC 6455 Section 5.2 + + 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|M| Payload len | Extended payload length | + |I|S|S|S| (4) |A| (7) | (16/64) | + |N|V|V|V| |S| | (if payload len==126/127) | + | |1|2|3| |K| | | + +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - + + | Extended payload length continued, if payload len == 127 | + + - - - - - - - - - - - - - - - +-------------------------------+ + | |Masking-key, if MASK set to 1 | + +-------------------------------+-------------------------------+ + | Masking-key (continued) | Payload Data | + +-------------------------------- - - - - - - - - - - - - - - - + + : Payload Data continued ... : + + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + | Payload Data continued ... | + +---------------------------------------------------------------+ +*/ + +static ssize_t ws_enc_write_head(struct Curl_easy *data, + struct ws_encoder *enc, + unsigned int flags, + curl_off_t payload_len, + struct bufq *out, + CURLcode *err) +{ + unsigned char firstbyte = 0; + unsigned char opcode; + unsigned char head[14]; + size_t hlen; + ssize_t n; + + if(enc->payload_remain > 0) { + /* trying to write a new frame before the previous one is finished */ + failf(data, "WS: starting new frame with %zd bytes from last one" + "remaining to be sent", (ssize_t)enc->payload_remain); + *err = CURLE_SEND_ERROR; + return -1; + } + + opcode = ws_frame_flags2op(flags); + if(!opcode) { + failf(data, "WS: provided flags not recognized '%x'", flags); + *err = CURLE_SEND_ERROR; + return -1; + } + + if(!(flags & CURLWS_CONT)) { + if(!enc->contfragment) + /* not marked as continuing, this is the final fragment */ + firstbyte |= WSBIT_FIN | opcode; + else + /* marked as continuing, this is the final fragment; set CONT + opcode and FIN bit */ + firstbyte |= WSBIT_FIN | WSBIT_OPCODE_CONT; + + enc->contfragment = FALSE; + } + else if(enc->contfragment) { + /* the previous fragment was not a final one and this isn't either, keep a + CONT opcode and no FIN bit */ + firstbyte |= WSBIT_OPCODE_CONT; + } + else { + firstbyte = opcode; + enc->contfragment = TRUE; + } + + head[0] = enc->firstbyte = firstbyte; + if(payload_len > 65535) { + head[1] = 127 | WSBIT_MASK; + head[2] = (unsigned char)((payload_len >> 56) & 0xff); + head[3] = (unsigned char)((payload_len >> 48) & 0xff); + head[4] = (unsigned char)((payload_len >> 40) & 0xff); + head[5] = (unsigned char)((payload_len >> 32) & 0xff); + head[6] = (unsigned char)((payload_len >> 24) & 0xff); + head[7] = (unsigned char)((payload_len >> 16) & 0xff); + head[8] = (unsigned char)((payload_len >> 8) & 0xff); + head[9] = (unsigned char)(payload_len & 0xff); + hlen = 10; + } + else if(payload_len >= 126) { + head[1] = 126 | WSBIT_MASK; + head[2] = (unsigned char)((payload_len >> 8) & 0xff); + head[3] = (unsigned char)(payload_len & 0xff); + hlen = 4; + } + else { + head[1] = (unsigned char)payload_len | WSBIT_MASK; + hlen = 2; + } + + enc->payload_remain = enc->payload_len = payload_len; + ws_enc_info(enc, data, "sending"); + + /* add 4 bytes mask */ + memcpy(&head[hlen], &enc->mask, 4); + hlen += 4; + /* reset for payload to come */ + enc->xori = 0; + + n = Curl_bufq_write(out, head, hlen, err); + if(n < 0) + return -1; + if((size_t)n != hlen) { + /* We use a bufq with SOFT_LIMIT, writing should always succeed */ + DEBUGASSERT(0); + *err = CURLE_SEND_ERROR; + return -1; + } + return n; +} + +static ssize_t ws_enc_write_payload(struct ws_encoder *enc, + struct Curl_easy *data, + const unsigned char *buf, size_t buflen, + struct bufq *out, CURLcode *err) +{ + ssize_t n; + size_t i, len; + + if(Curl_bufq_is_full(out)) { + *err = CURLE_AGAIN; + return -1; + } + + /* not the most performant way to do this */ + len = buflen; + if((curl_off_t)len > enc->payload_remain) + len = (size_t)enc->payload_remain; + + for(i = 0; i < len; ++i) { + unsigned char c = buf[i] ^ enc->mask[enc->xori]; + n = Curl_bufq_write(out, &c, 1, err); + if(n < 0) { + if((*err != CURLE_AGAIN) || !i) + return -1; + break; + } + enc->xori++; + enc->xori &= 3; + } + enc->payload_remain -= (curl_off_t)i; + ws_enc_info(enc, data, "buffered"); + return (ssize_t)i; +} + + +struct wsfield { + const char *name; + const char *val; +}; + +CURLcode Curl_ws_request(struct Curl_easy *data, REQTYPE *req) +{ + unsigned int i; + CURLcode result = CURLE_OK; + unsigned char rand[16]; + char *randstr; + size_t randlen; + char keyval[40]; + struct SingleRequest *k = &data->req; + struct wsfield heads[]= { + { + /* The request MUST contain an |Upgrade| header field whose value + MUST include the "websocket" keyword. */ + "Upgrade:", "websocket" + }, + { + /* The request MUST contain a |Connection| header field whose value + MUST include the "Upgrade" token. */ + "Connection:", "Upgrade", + }, + { + /* The request MUST include a header field with the name + |Sec-WebSocket-Version|. The value of this header field MUST be + 13. */ + "Sec-WebSocket-Version:", "13", + }, + { + /* The request MUST include a header field with the name + |Sec-WebSocket-Key|. The value of this header field MUST be a nonce + consisting of a randomly selected 16-byte value that has been + base64-encoded (see Section 4 of [RFC4648]). The nonce MUST be + selected randomly for each connection. */ + "Sec-WebSocket-Key:", NULL, + } + }; + heads[3].val = &keyval[0]; + + /* 16 bytes random */ + result = Curl_rand(data, (unsigned char *)rand, sizeof(rand)); + if(result) + return result; + result = Curl_base64_encode((char *)rand, sizeof(rand), &randstr, &randlen); + if(result) + return result; + DEBUGASSERT(randlen < sizeof(keyval)); + if(randlen >= sizeof(keyval)) + return CURLE_FAILED_INIT; + strcpy(keyval, randstr); + free(randstr); + for(i = 0; !result && (i < sizeof(heads)/sizeof(heads[0])); i++) { + if(!Curl_checkheaders(data, STRCONST(heads[i].name))) { +#ifdef USE_HYPER + char field[128]; + msnprintf(field, sizeof(field), "%s %s", heads[i].name, + heads[i].val); + result = Curl_hyper_header(data, req, field); +#else + (void)data; + result = Curl_dyn_addf(req, "%s %s\r\n", heads[i].name, + heads[i].val); +#endif + } + } + k->upgr101 = UPGR101_WS; + return result; +} + +/* + * 'nread' is number of bytes of websocket data already in the buffer at + * 'mem'. + */ +CURLcode Curl_ws_accept(struct Curl_easy *data, + const char *mem, size_t nread) +{ + struct SingleRequest *k = &data->req; + struct websocket *ws; + CURLcode result; + + DEBUGASSERT(data->conn); + ws = data->conn->proto.ws; + if(!ws) { + ws = calloc(1, sizeof(*ws)); + if(!ws) + return CURLE_OUT_OF_MEMORY; + data->conn->proto.ws = ws; + Curl_bufq_init(&ws->recvbuf, WS_CHUNK_SIZE, WS_CHUNK_COUNT); + Curl_bufq_init2(&ws->sendbuf, WS_CHUNK_SIZE, WS_CHUNK_COUNT, + BUFQ_OPT_SOFT_LIMIT); + ws_dec_init(&ws->dec); + ws_enc_init(&ws->enc); + } + else { + Curl_bufq_reset(&ws->recvbuf); + ws_dec_reset(&ws->dec); + ws_enc_reset(&ws->enc); + } + /* Verify the Sec-WebSocket-Accept response. + + The sent value is the base64 encoded version of a SHA-1 hash done on the + |Sec-WebSocket-Key| header field concatenated with + the string "258EAFA5-E914-47DA-95CA-C5AB0DC85B11". + */ + + /* If the response includes a |Sec-WebSocket-Extensions| header field and + this header field indicates the use of an extension that was not present + in the client's handshake (the server has indicated an extension not + requested by the client), the client MUST Fail the WebSocket Connection. + */ + + /* If the response includes a |Sec-WebSocket-Protocol| header field + and this header field indicates the use of a subprotocol that was + not present in the client's handshake (the server has indicated a + subprotocol not requested by the client), the client MUST Fail + the WebSocket Connection. */ + + /* 4 bytes random */ + + result = Curl_rand(data, (unsigned char *)&ws->enc.mask, + sizeof(ws->enc.mask)); + if(result) + return result; + infof(data, "Received 101, switch to WebSocket; mask %02x%02x%02x%02x", + ws->enc.mask[0], ws->enc.mask[1], ws->enc.mask[2], ws->enc.mask[3]); + + if(data->set.connect_only) { + ssize_t nwritten; + /* In CONNECT_ONLY setup, the payloads from `mem` need to be received + * when using `curl_ws_recv` later on after this transfer is already + * marked as DONE. */ + nwritten = Curl_bufq_write(&ws->recvbuf, (const unsigned char *)mem, + nread, &result); + if(nwritten < 0) + return result; + infof(data, "%zu bytes websocket payload", nread); + } + k->upgr101 = UPGR101_RECEIVED; + + return result; +} + +static ssize_t ws_client_write(const unsigned char *buf, size_t buflen, + int frame_age, int frame_flags, + curl_off_t payload_offset, + curl_off_t payload_len, + void *userp, + CURLcode *err) +{ + struct Curl_easy *data = userp; + struct websocket *ws; + size_t wrote; + curl_off_t remain = (payload_len - (payload_offset + buflen)); + + (void)frame_age; + if(!data->conn || !data->conn->proto.ws) { + *err = CURLE_FAILED_INIT; + return -1; + } + ws = data->conn->proto.ws; + + if((frame_flags & CURLWS_PING) && !remain) { + /* auto-respond to PINGs, only works for single-frame payloads atm */ + size_t bytes; + infof(data, "WS: auto-respond to PING with a PONG"); + /* send back the exact same content as a PONG */ + *err = curl_ws_send(data, buf, buflen, &bytes, 0, CURLWS_PONG); + if(*err) + return -1; + } + else if(buflen || !remain) { + /* deliver the decoded frame to the user callback. The application + * may invoke curl_ws_meta() to access frame information. */ + update_meta(ws, frame_age, frame_flags, payload_offset, + payload_len, buflen); + Curl_set_in_callback(data, true); + wrote = data->set.fwrite_func((char *)buf, 1, + buflen, data->set.out); + Curl_set_in_callback(data, false); + if(wrote != buflen) { + *err = CURLE_RECV_ERROR; + return -1; + } + } + *err = CURLE_OK; + return (ssize_t)buflen; +} + +/* Curl_ws_writecb() is the write callback for websocket traffic. The + websocket data is provided to this raw, in chunks. This function should + handle/decode the data and call the "real" underlying callback accordingly. +*/ +size_t Curl_ws_writecb(char *buffer, size_t size /* 1 */, + size_t nitems, void *userp) +{ + struct Curl_easy *data = userp; + + if(data->set.ws_raw_mode) + return data->set.fwrite_func(buffer, size, nitems, data->set.out); + else if(nitems) { + struct websocket *ws; + CURLcode result; + + if(!data->conn || !data->conn->proto.ws) { + failf(data, "WS: not a websocket transfer"); + return nitems - 1; + } + ws = data->conn->proto.ws; + + if(buffer) { + ssize_t nwritten; + + nwritten = Curl_bufq_write(&ws->recvbuf, (const unsigned char *)buffer, + nitems, &result); + if(nwritten < 0) { + infof(data, "WS: error adding data to buffer %d", (int)result); + return nitems - 1; + } + buffer = NULL; + } + + while(!Curl_bufq_is_empty(&ws->recvbuf)) { + + result = ws_dec_pass(&ws->dec, data, &ws->recvbuf, + ws_client_write, data); + if(result == CURLE_AGAIN) + /* insufficient amount of data, keep it for later. + * we pretend to have written all since we have a copy */ + return nitems; + else if(result) { + infof(data, "WS: decode error %d", (int)result); + return nitems - 1; + } + } + } + return nitems; +} + +struct ws_collect { + struct Curl_easy *data; + void *buffer; + size_t buflen; + size_t bufidx; + int frame_age; + int frame_flags; + curl_off_t payload_offset; + curl_off_t payload_len; + bool written; +}; + +static ssize_t ws_client_collect(const unsigned char *buf, size_t buflen, + int frame_age, int frame_flags, + curl_off_t payload_offset, + curl_off_t payload_len, + void *userp, + CURLcode *err) +{ + struct ws_collect *ctx = userp; + size_t nwritten; + curl_off_t remain = (payload_len - (payload_offset + buflen)); + + if(!ctx->bufidx) { + /* first write */ + ctx->frame_age = frame_age; + ctx->frame_flags = frame_flags; + ctx->payload_offset = payload_offset; + ctx->payload_len = payload_len; + } + + if((frame_flags & CURLWS_PING) && !remain) { + /* auto-respond to PINGs, only works for single-frame payloads atm */ + size_t bytes; + infof(ctx->data, "WS: auto-respond to PING with a PONG"); + /* send back the exact same content as a PONG */ + *err = curl_ws_send(ctx->data, buf, buflen, &bytes, 0, CURLWS_PONG); + if(*err) + return -1; + nwritten = bytes; + } + else { + ctx->written = TRUE; + DEBUGASSERT(ctx->buflen >= ctx->bufidx); + nwritten = CURLMIN(buflen, ctx->buflen - ctx->bufidx); + if(!nwritten) { + if(!buflen) { /* 0 length write, we accept that */ + *err = CURLE_OK; + return 0; + } + *err = CURLE_AGAIN; /* no more space */ + return -1; + } + *err = CURLE_OK; + memcpy(ctx->buffer, buf, nwritten); + ctx->bufidx += nwritten; + } + return nwritten; +} + +static ssize_t nw_in_recv(void *reader_ctx, + unsigned char *buf, size_t buflen, + CURLcode *err) +{ + struct Curl_easy *data = reader_ctx; + size_t nread; + + *err = curl_easy_recv(data, buf, buflen, &nread); + if(*err) + return -1; + return (ssize_t)nread; +} + +CURL_EXTERN CURLcode curl_ws_recv(struct Curl_easy *data, void *buffer, + size_t buflen, size_t *nread, + const struct curl_ws_frame **metap) +{ + struct connectdata *conn = data->conn; + struct websocket *ws; + bool done = FALSE; /* not filled passed buffer yet */ + struct ws_collect ctx; + CURLcode result; + + if(!conn) { + /* Unhappy hack with lifetimes of transfers and connection */ + if(!data->set.connect_only) { + failf(data, "CONNECT_ONLY is required"); + return CURLE_UNSUPPORTED_PROTOCOL; + } + + Curl_getconnectinfo(data, &conn); + if(!conn) { + failf(data, "connection not found"); + return CURLE_BAD_FUNCTION_ARGUMENT; + } + } + ws = conn->proto.ws; + if(!ws) { + failf(data, "connection is not setup for websocket"); + return CURLE_BAD_FUNCTION_ARGUMENT; + } + + *nread = 0; + *metap = NULL; + /* get a download buffer */ + result = Curl_preconnect(data); + if(result) + return result; + + memset(&ctx, 0, sizeof(ctx)); + ctx.data = data; + ctx.buffer = buffer; + ctx.buflen = buflen; + + while(!done) { + /* receive more when our buffer is empty */ + if(Curl_bufq_is_empty(&ws->recvbuf)) { + ssize_t n = Curl_bufq_slurp(&ws->recvbuf, nw_in_recv, data, &result); + if(n < 0) { + return result; + } + else if(n == 0) { + /* connection closed */ + infof(data, "connection expectedly closed?"); + return CURLE_GOT_NOTHING; + } + DEBUGF(infof(data, "curl_ws_recv, added %zu bytes from network", + Curl_bufq_len(&ws->recvbuf))); + } + + result = ws_dec_pass(&ws->dec, data, &ws->recvbuf, + ws_client_collect, &ctx); + if(result == CURLE_AGAIN) { + if(!ctx.written) { + ws_dec_info(&ws->dec, data, "need more input"); + continue; /* nothing written, try more input */ + } + done = TRUE; + break; + } + else if(result) { + return result; + } + else if(ctx.written) { + /* The decoded frame is passed back to our caller. + * There are frames like PING were we auto-respond to and + * that we do not return. For these `ctx.written` is not set. */ + done = TRUE; + break; + } + } + + /* update frame information to be passed back */ + update_meta(ws, ctx.frame_age, ctx.frame_flags, ctx.payload_offset, + ctx.payload_len, ctx.bufidx); + *metap = &ws->frame; + *nread = ws->frame.len; + /* infof(data, "curl_ws_recv(len=%zu) -> %zu bytes (frame at %" + CURL_FORMAT_CURL_OFF_T ", %" CURL_FORMAT_CURL_OFF_T " left)", + buflen, *nread, ws->frame.offset, ws->frame.bytesleft); */ + return CURLE_OK; +} + +static CURLcode ws_flush(struct Curl_easy *data, struct websocket *ws, + bool complete) +{ + if(!Curl_bufq_is_empty(&ws->sendbuf)) { + CURLcode result; + const unsigned char *out; + size_t outlen; + ssize_t n; + + while(Curl_bufq_peek(&ws->sendbuf, &out, &outlen)) { + if(data->set.connect_only) + result = Curl_senddata(data, out, outlen, &n); + else + result = Curl_write(data, data->conn->writesockfd, out, outlen, &n); + if(result) { + if(result == CURLE_AGAIN) { + if(!complete) { + infof(data, "WS: flush EAGAIN, %zu bytes remain in buffer", + Curl_bufq_len(&ws->sendbuf)); + return result; + } + /* TODO: the current design does not allow for buffered writes. + * We need to flush the buffer now. There is no ws_flush() later */ + n = 0; + continue; + } + else if(result) { + failf(data, "WS: flush, write error %d", result); + return result; + } + } + else { + infof(data, "WS: flushed %zu bytes", (size_t)n); + Curl_bufq_skip(&ws->sendbuf, (size_t)n); + } + } + } + return CURLE_OK; +} + +CURL_EXTERN CURLcode curl_ws_send(CURL *data, const void *buffer, + size_t buflen, size_t *sent, + curl_off_t fragsize, + unsigned int flags) +{ + struct websocket *ws; + ssize_t nwritten, n; + size_t space; + CURLcode result; + + *sent = 0; + if(!data->conn && data->set.connect_only) { + result = Curl_connect_only_attach(data); + if(result) + return result; + } + if(!data->conn) { + failf(data, "No associated connection"); + return CURLE_SEND_ERROR; + } + if(!data->conn->proto.ws) { + failf(data, "Not a websocket transfer"); + return CURLE_SEND_ERROR; + } + ws = data->conn->proto.ws; + + if(data->set.ws_raw_mode) { + if(fragsize || flags) + return CURLE_BAD_FUNCTION_ARGUMENT; + if(!buflen) + /* nothing to do */ + return CURLE_OK; + /* raw mode sends exactly what was requested, and this is from within + the write callback */ + if(Curl_is_in_callback(data)) { + result = Curl_write(data, data->conn->writesockfd, buffer, buflen, + &nwritten); + } + else + result = Curl_senddata(data, buffer, buflen, &nwritten); + + infof(data, "WS: wanted to send %zu bytes, sent %zu bytes", + buflen, nwritten); + *sent = (nwritten >= 0)? (size_t)nwritten : 0; + return result; + } + + /* Not RAW mode, buf we do the frame encoding */ + result = ws_flush(data, ws, FALSE); + if(result) + return result; + + /* TODO: the current design does not allow partial writes, afaict. + * It is not clear who the application is supposed to react. */ + space = Curl_bufq_space(&ws->sendbuf); + DEBUGF(infof(data, "curl_ws_send(len=%zu), sendbuf len=%zu space %zu", + buflen, Curl_bufq_len(&ws->sendbuf), space)); + if(space < 14) + return CURLE_AGAIN; + + if(flags & CURLWS_OFFSET) { + if(fragsize) { + /* a frame series 'fragsize' bytes big, this is the first */ + n = ws_enc_write_head(data, &ws->enc, flags, fragsize, + &ws->sendbuf, &result); + if(n < 0) + return result; + } + else { + if((curl_off_t)buflen > ws->enc.payload_remain) { + infof(data, "WS: unaligned frame size (sending %zu instead of %" + CURL_FORMAT_CURL_OFF_T ")", + buflen, ws->enc.payload_remain); + } + } + } + else if(!ws->enc.payload_remain) { + n = ws_enc_write_head(data, &ws->enc, flags, (curl_off_t)buflen, + &ws->sendbuf, &result); + if(n < 0) + return result; + } + + n = ws_enc_write_payload(&ws->enc, data, + buffer, buflen, &ws->sendbuf, &result); + if(n < 0) + return result; + + *sent = (size_t)n; + return ws_flush(data, ws, TRUE); +} + +static void ws_free(struct connectdata *conn) +{ + if(conn && conn->proto.ws) { + Curl_bufq_free(&conn->proto.ws->recvbuf); + Curl_bufq_free(&conn->proto.ws->sendbuf); + Curl_safefree(conn->proto.ws); + } +} + +void Curl_ws_done(struct Curl_easy *data) +{ + (void)data; +} + +CURLcode Curl_ws_disconnect(struct Curl_easy *data, + struct connectdata *conn, + bool dead_connection) +{ + (void)data; + (void)dead_connection; + ws_free(conn); + return CURLE_OK; +} + +CURL_EXTERN const struct curl_ws_frame *curl_ws_meta(struct Curl_easy *data) +{ + /* we only return something for websocket, called from within the callback + when not using raw mode */ + if(GOOD_EASY_HANDLE(data) && Curl_is_in_callback(data) && data->conn && + data->conn->proto.ws && !data->set.ws_raw_mode) + return &data->conn->proto.ws->frame; + return NULL; +} + +#else + +CURL_EXTERN CURLcode curl_ws_recv(CURL *curl, void *buffer, size_t buflen, + size_t *nread, + const struct curl_ws_frame **metap) +{ + (void)curl; + (void)buffer; + (void)buflen; + (void)nread; + (void)metap; + return CURLE_NOT_BUILT_IN; +} + +CURL_EXTERN CURLcode curl_ws_send(CURL *curl, const void *buffer, + size_t buflen, size_t *sent, + curl_off_t fragsize, + unsigned int flags) +{ + (void)curl; + (void)buffer; + (void)buflen; + (void)sent; + (void)fragsize; + (void)flags; + return CURLE_NOT_BUILT_IN; +} + +CURL_EXTERN const struct curl_ws_frame *curl_ws_meta(struct Curl_easy *data) +{ + (void)data; + return NULL; +} +#endif /* USE_WEBSOCKETS */ |