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Diffstat (limited to 'Utilities/cmcurl/lib/http_chunks.c')
| -rw-r--r-- | Utilities/cmcurl/lib/http_chunks.c | 319 |
1 files changed, 319 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/http_chunks.c b/Utilities/cmcurl/lib/http_chunks.c new file mode 100644 index 0000000..bda00d3 --- /dev/null +++ b/Utilities/cmcurl/lib/http_chunks.c @@ -0,0 +1,319 @@ +/*************************************************************************** + * _ _ ____ _ + * 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" + +#ifndef CURL_DISABLE_HTTP + +#include "urldata.h" /* it includes http_chunks.h */ +#include "sendf.h" /* for the client write stuff */ +#include "dynbuf.h" +#include "content_encoding.h" +#include "http.h" +#include "strtoofft.h" +#include "warnless.h" + +/* The last #include files should be: */ +#include "curl_memory.h" +#include "memdebug.h" + +/* + * Chunk format (simplified): + * + * <HEX SIZE>[ chunk extension ] CRLF + * <DATA> CRLF + * + * Highlights from RFC2616 section 3.6 say: + + The chunked encoding modifies the body of a message in order to + transfer it as a series of chunks, each with its own size indicator, + followed by an OPTIONAL trailer containing entity-header fields. This + allows dynamically produced content to be transferred along with the + information necessary for the recipient to verify that it has + received the full message. + + Chunked-Body = *chunk + last-chunk + trailer + CRLF + + chunk = chunk-size [ chunk-extension ] CRLF + chunk-data CRLF + chunk-size = 1*HEX + last-chunk = 1*("0") [ chunk-extension ] CRLF + + chunk-extension= *( ";" chunk-ext-name [ "=" chunk-ext-val ] ) + chunk-ext-name = token + chunk-ext-val = token | quoted-string + chunk-data = chunk-size(OCTET) + trailer = *(entity-header CRLF) + + The chunk-size field is a string of hex digits indicating the size of + the chunk. The chunked encoding is ended by any chunk whose size is + zero, followed by the trailer, which is terminated by an empty line. + + */ + +#define isxdigit_ascii(x) Curl_isxdigit(x) + +void Curl_httpchunk_init(struct Curl_easy *data) +{ + struct connectdata *conn = data->conn; + struct Curl_chunker *chunk = &conn->chunk; + chunk->hexindex = 0; /* start at 0 */ + chunk->state = CHUNK_HEX; /* we get hex first! */ + Curl_dyn_init(&conn->trailer, DYN_H1_TRAILER); +} + +/* + * chunk_read() returns a OK for normal operations, or a positive return code + * for errors. STOP means this sequence of chunks is complete. The 'wrote' + * argument is set to tell the caller how many bytes we actually passed to the + * client (for byte-counting and whatever). + * + * The states and the state-machine is further explained in the header file. + * + * This function always uses ASCII hex values to accommodate non-ASCII hosts. + * For example, 0x0d and 0x0a are used instead of '\r' and '\n'. + */ +CHUNKcode Curl_httpchunk_read(struct Curl_easy *data, + char *datap, + ssize_t datalen, + ssize_t *wrote, + CURLcode *extrap) +{ + CURLcode result = CURLE_OK; + struct connectdata *conn = data->conn; + struct Curl_chunker *ch = &conn->chunk; + struct SingleRequest *k = &data->req; + size_t piece; + curl_off_t length = (curl_off_t)datalen; + + *wrote = 0; /* nothing's written yet */ + + /* the original data is written to the client, but we go on with the + chunk read process, to properly calculate the content length */ + if(data->set.http_te_skip && !k->ignorebody) { + result = Curl_client_write(data, CLIENTWRITE_BODY, datap, datalen); + if(result) { + *extrap = result; + return CHUNKE_PASSTHRU_ERROR; + } + } + + while(length) { + switch(ch->state) { + case CHUNK_HEX: + if(ISXDIGIT(*datap)) { + if(ch->hexindex < CHUNK_MAXNUM_LEN) { + ch->hexbuffer[ch->hexindex] = *datap; + datap++; + length--; + ch->hexindex++; + } + else { + return CHUNKE_TOO_LONG_HEX; /* longer hex than we support */ + } + } + else { + char *endptr; + if(0 == ch->hexindex) + /* This is illegal data, we received junk where we expected + a hexadecimal digit. */ + return CHUNKE_ILLEGAL_HEX; + + /* length and datap are unmodified */ + ch->hexbuffer[ch->hexindex] = 0; + + if(curlx_strtoofft(ch->hexbuffer, &endptr, 16, &ch->datasize)) + return CHUNKE_ILLEGAL_HEX; + ch->state = CHUNK_LF; /* now wait for the CRLF */ + } + break; + + case CHUNK_LF: + /* waiting for the LF after a chunk size */ + if(*datap == 0x0a) { + /* we're now expecting data to come, unless size was zero! */ + if(0 == ch->datasize) { + ch->state = CHUNK_TRAILER; /* now check for trailers */ + } + else + ch->state = CHUNK_DATA; + } + + datap++; + length--; + break; + + case CHUNK_DATA: + /* We expect 'datasize' of data. We have 'length' right now, it can be + more or less than 'datasize'. Get the smallest piece. + */ + piece = curlx_sotouz((ch->datasize >= length)?length:ch->datasize); + + /* Write the data portion available */ + if(!data->set.http_te_skip && !k->ignorebody) { + if(!data->set.http_ce_skip && k->writer_stack) + result = Curl_unencode_write(data, k->writer_stack, datap, piece); + else + result = Curl_client_write(data, CLIENTWRITE_BODY, datap, piece); + + if(result) { + *extrap = result; + return CHUNKE_PASSTHRU_ERROR; + } + } + + *wrote += piece; + ch->datasize -= piece; /* decrease amount left to expect */ + datap += piece; /* move read pointer forward */ + length -= piece; /* decrease space left in this round */ + + if(0 == ch->datasize) + /* end of data this round, we now expect a trailing CRLF */ + ch->state = CHUNK_POSTLF; + break; + + case CHUNK_POSTLF: + if(*datap == 0x0a) { + /* The last one before we go back to hex state and start all over. */ + Curl_httpchunk_init(data); /* sets state back to CHUNK_HEX */ + } + else if(*datap != 0x0d) + return CHUNKE_BAD_CHUNK; + datap++; + length--; + break; + + case CHUNK_TRAILER: + if((*datap == 0x0d) || (*datap == 0x0a)) { + char *tr = Curl_dyn_ptr(&conn->trailer); + /* this is the end of a trailer, but if the trailer was zero bytes + there was no trailer and we move on */ + + if(tr) { + size_t trlen; + result = Curl_dyn_addn(&conn->trailer, (char *)STRCONST("\x0d\x0a")); + if(result) + return CHUNKE_OUT_OF_MEMORY; + + tr = Curl_dyn_ptr(&conn->trailer); + trlen = Curl_dyn_len(&conn->trailer); + if(!data->set.http_te_skip) { + result = Curl_client_write(data, + CLIENTWRITE_HEADER|CLIENTWRITE_TRAILER, + tr, trlen); + if(result) { + *extrap = result; + return CHUNKE_PASSTHRU_ERROR; + } + } + Curl_dyn_reset(&conn->trailer); + ch->state = CHUNK_TRAILER_CR; + if(*datap == 0x0a) + /* already on the LF */ + break; + } + else { + /* no trailer, we're on the final CRLF pair */ + ch->state = CHUNK_TRAILER_POSTCR; + break; /* don't advance the pointer */ + } + } + else { + result = Curl_dyn_addn(&conn->trailer, datap, 1); + if(result) + return CHUNKE_OUT_OF_MEMORY; + } + datap++; + length--; + break; + + case CHUNK_TRAILER_CR: + if(*datap == 0x0a) { + ch->state = CHUNK_TRAILER_POSTCR; + datap++; + length--; + } + else + return CHUNKE_BAD_CHUNK; + break; + + case CHUNK_TRAILER_POSTCR: + /* We enter this state when a CR should arrive so we expect to + have to first pass a CR before we wait for LF */ + if((*datap != 0x0d) && (*datap != 0x0a)) { + /* not a CR then it must be another header in the trailer */ + ch->state = CHUNK_TRAILER; + break; + } + if(*datap == 0x0d) { + /* skip if CR */ + datap++; + length--; + } + /* now wait for the final LF */ + ch->state = CHUNK_STOP; + break; + + case CHUNK_STOP: + if(*datap == 0x0a) { + length--; + + /* Record the length of any data left in the end of the buffer + even if there's no more chunks to read */ + ch->datasize = curlx_sotouz(length); + + return CHUNKE_STOP; /* return stop */ + } + else + return CHUNKE_BAD_CHUNK; + } + } + return CHUNKE_OK; +} + +const char *Curl_chunked_strerror(CHUNKcode code) +{ + switch(code) { + default: + return "OK"; + case CHUNKE_TOO_LONG_HEX: + return "Too long hexadecimal number"; + case CHUNKE_ILLEGAL_HEX: + return "Illegal or missing hexadecimal sequence"; + case CHUNKE_BAD_CHUNK: + return "Malformed encoding found"; + case CHUNKE_PASSTHRU_ERROR: + DEBUGASSERT(0); /* never used */ + return ""; + case CHUNKE_BAD_ENCODING: + return "Bad content-encoding found"; + case CHUNKE_OUT_OF_MEMORY: + return "Out of memory"; + } +} + +#endif /* CURL_DISABLE_HTTP */ |