| /*************************************************************************** |
| * _ _ ____ _ |
| * 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 "urldata.h" |
| #include <curl/curl.h> |
| #include <stddef.h> |
| |
| #ifdef HAVE_LIBZ |
| #include <cm3p/zlib.h> |
| #endif |
| |
| #ifdef HAVE_BROTLI |
| #if defined(__GNUC__) || defined(__clang__) |
| /* Ignore -Wvla warnings in brotli headers */ |
| #pragma GCC diagnostic push |
| #pragma GCC diagnostic ignored "-Wvla" |
| #endif |
| #include <brotli/decode.h> |
| #if defined(__GNUC__) || defined(__clang__) |
| #pragma GCC diagnostic pop |
| #endif |
| #endif |
| |
| #ifdef HAVE_ZSTD |
| #include <zstd.h> |
| #endif |
| |
| #include "sendf.h" |
| #include "http.h" |
| #include "content_encoding.h" |
| |
| /* The last 2 #include files should be in this order */ |
| #include "curl_memory.h" |
| #include "memdebug.h" |
| |
| #define CONTENT_ENCODING_DEFAULT "identity" |
| |
| #ifndef CURL_DISABLE_HTTP |
| |
| /* allow no more than 5 "chained" compression steps */ |
| #define MAX_ENCODE_STACK 5 |
| |
| #if defined(HAVE_LIBZ) || defined(HAVE_BROTLI) || defined(HAVE_ZSTD) |
| #define DECOMPRESS_BUFFER_SIZE 16384 /* buffer size for decompressed data */ |
| #endif |
| |
| #ifdef HAVE_LIBZ |
| |
| #if !defined(ZLIB_VERNUM) || (ZLIB_VERNUM < 0x1252) |
| #error "requires zlib 1.2.5.2 or newer" |
| #endif |
| |
| typedef enum { |
| ZLIB_UNINIT, /* uninitialized */ |
| ZLIB_INIT, /* initialized */ |
| ZLIB_INFLATING, /* inflating started. */ |
| ZLIB_EXTERNAL_TRAILER, /* reading external trailer */ |
| ZLIB_INIT_GZIP /* initialized in transparent gzip mode */ |
| } zlibInitState; |
| |
| /* Deflate and gzip writer. */ |
| struct zlib_writer { |
| struct Curl_cwriter super; |
| zlibInitState zlib_init; /* zlib init state */ |
| char buffer[DECOMPRESS_BUFFER_SIZE]; /* Put the decompressed data here. */ |
| uInt trailerlen; /* Remaining trailer byte count. */ |
| z_stream z; /* State structure for zlib. */ |
| }; |
| |
| |
| static voidpf |
| zalloc_cb(voidpf opaque, unsigned int items, unsigned int size) |
| { |
| (void)opaque; |
| /* not a typo, keep it calloc() */ |
| return (voidpf) calloc(items, size); |
| } |
| |
| static void |
| zfree_cb(voidpf opaque, voidpf ptr) |
| { |
| (void)opaque; |
| free(ptr); |
| } |
| |
| static CURLcode |
| process_zlib_error(struct Curl_easy *data, z_stream *z) |
| { |
| if(z->msg) |
| failf(data, "Error while processing content unencoding: %s", |
| z->msg); |
| else |
| failf(data, "Error while processing content unencoding: " |
| "Unknown failure within decompression software."); |
| |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| |
| static CURLcode |
| exit_zlib(struct Curl_easy *data, |
| z_stream *z, zlibInitState *zlib_init, CURLcode result) |
| { |
| if(*zlib_init != ZLIB_UNINIT) { |
| if(inflateEnd(z) != Z_OK && result == CURLE_OK) |
| result = process_zlib_error(data, z); |
| *zlib_init = ZLIB_UNINIT; |
| } |
| |
| return result; |
| } |
| |
| static CURLcode process_trailer(struct Curl_easy *data, |
| struct zlib_writer *zp) |
| { |
| z_stream *z = &zp->z; |
| CURLcode result = CURLE_OK; |
| uInt len = z->avail_in < zp->trailerlen ? z->avail_in : zp->trailerlen; |
| |
| /* Consume expected trailer bytes. Terminate stream if exhausted. |
| Issue an error if unexpected bytes follow. */ |
| |
| zp->trailerlen -= len; |
| z->avail_in -= len; |
| z->next_in += len; |
| if(z->avail_in) |
| result = CURLE_WRITE_ERROR; |
| if(result || !zp->trailerlen) |
| result = exit_zlib(data, z, &zp->zlib_init, result); |
| else { |
| /* Only occurs for gzip with zlib < 1.2.0.4 or raw deflate. */ |
| zp->zlib_init = ZLIB_EXTERNAL_TRAILER; |
| } |
| return result; |
| } |
| |
| static CURLcode inflate_stream(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| zlibInitState started) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| uInt nread = z->avail_in; |
| z_const Bytef *orig_in = z->next_in; |
| bool done = FALSE; |
| CURLcode result = CURLE_OK; /* Curl_client_write status */ |
| |
| /* Check state. */ |
| if(zp->zlib_init != ZLIB_INIT && |
| zp->zlib_init != ZLIB_INFLATING && |
| zp->zlib_init != ZLIB_INIT_GZIP) |
| return exit_zlib(data, z, &zp->zlib_init, CURLE_WRITE_ERROR); |
| |
| /* because the buffer size is fixed, iteratively decompress and transfer to |
| the client via next_write function. */ |
| while(!done) { |
| int status; /* zlib status */ |
| done = TRUE; |
| |
| /* (re)set buffer for decompressed output for every iteration */ |
| z->next_out = (Bytef *) zp->buffer; |
| z->avail_out = DECOMPRESS_BUFFER_SIZE; |
| |
| status = inflate(z, Z_BLOCK); |
| |
| /* Flush output data if some. */ |
| if(z->avail_out != DECOMPRESS_BUFFER_SIZE) { |
| if(status == Z_OK || status == Z_STREAM_END) { |
| zp->zlib_init = started; /* Data started. */ |
| result = Curl_cwriter_write(data, writer->next, type, zp->buffer, |
| DECOMPRESS_BUFFER_SIZE - z->avail_out); |
| if(result) { |
| exit_zlib(data, z, &zp->zlib_init, result); |
| break; |
| } |
| } |
| } |
| |
| /* Dispatch by inflate() status. */ |
| switch(status) { |
| case Z_OK: |
| /* Always loop: there may be unflushed latched data in zlib state. */ |
| done = FALSE; |
| break; |
| case Z_BUF_ERROR: |
| /* No more data to flush: just exit loop. */ |
| break; |
| case Z_STREAM_END: |
| result = process_trailer(data, zp); |
| break; |
| case Z_DATA_ERROR: |
| /* some servers seem to not generate zlib headers, so this is an attempt |
| to fix and continue anyway */ |
| if(zp->zlib_init == ZLIB_INIT) { |
| if(inflateReset2(z, -MAX_WBITS) == Z_OK) { |
| z->next_in = orig_in; |
| z->avail_in = nread; |
| zp->zlib_init = ZLIB_INFLATING; |
| zp->trailerlen = 4; /* Tolerate up to 4 unknown trailer bytes. */ |
| done = FALSE; |
| break; |
| } |
| zp->zlib_init = ZLIB_UNINIT; /* inflateEnd() already called. */ |
| } |
| result = exit_zlib(data, z, &zp->zlib_init, process_zlib_error(data, z)); |
| break; |
| default: |
| result = exit_zlib(data, z, &zp->zlib_init, process_zlib_error(data, z)); |
| break; |
| } |
| } |
| |
| /* We are about to leave this call so the `nread' data bytes will not be seen |
| again. If we are in a state that would wrongly allow restart in raw mode |
| at the next call, assume output has already started. */ |
| if(nread && zp->zlib_init == ZLIB_INIT) |
| zp->zlib_init = started; /* Cannot restart anymore. */ |
| |
| return result; |
| } |
| |
| |
| /* Deflate handler. */ |
| static CURLcode deflate_do_init(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| /* Initialize zlib */ |
| z->zalloc = (alloc_func) zalloc_cb; |
| z->zfree = (free_func) zfree_cb; |
| |
| if(inflateInit(z) != Z_OK) |
| return process_zlib_error(data, z); |
| zp->zlib_init = ZLIB_INIT; |
| return CURLE_OK; |
| } |
| |
| static CURLcode deflate_do_write(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| const char *buf, size_t nbytes) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| if(!(type & CLIENTWRITE_BODY) || !nbytes) |
| return Curl_cwriter_write(data, writer->next, type, buf, nbytes); |
| |
| /* Set the compressed input when this function is called */ |
| z->next_in = (z_const Bytef *)buf; |
| z->avail_in = (uInt)nbytes; |
| |
| if(zp->zlib_init == ZLIB_EXTERNAL_TRAILER) |
| return process_trailer(data, zp); |
| |
| /* Now uncompress the data */ |
| return inflate_stream(data, writer, type, ZLIB_INFLATING); |
| } |
| |
| static void deflate_do_close(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| exit_zlib(data, z, &zp->zlib_init, CURLE_OK); |
| } |
| |
| static const struct Curl_cwtype deflate_encoding = { |
| "deflate", |
| NULL, |
| deflate_do_init, |
| deflate_do_write, |
| deflate_do_close, |
| sizeof(struct zlib_writer) |
| }; |
| |
| |
| /* Gzip handler. */ |
| static CURLcode gzip_do_init(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| /* Initialize zlib */ |
| z->zalloc = (alloc_func) zalloc_cb; |
| z->zfree = (free_func) zfree_cb; |
| |
| if(inflateInit2(z, MAX_WBITS + 32) != Z_OK) |
| return process_zlib_error(data, z); |
| |
| zp->zlib_init = ZLIB_INIT_GZIP; /* Transparent gzip decompress state */ |
| return CURLE_OK; |
| } |
| |
| static CURLcode gzip_do_write(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| const char *buf, size_t nbytes) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| if(!(type & CLIENTWRITE_BODY) || !nbytes) |
| return Curl_cwriter_write(data, writer->next, type, buf, nbytes); |
| |
| if(zp->zlib_init == ZLIB_INIT_GZIP) { |
| /* Let zlib handle the gzip decompression entirely */ |
| z->next_in = (z_const Bytef *)buf; |
| z->avail_in = (uInt)nbytes; |
| /* Now uncompress the data */ |
| return inflate_stream(data, writer, type, ZLIB_INIT_GZIP); |
| } |
| |
| /* We are running with an old version: return error. */ |
| return exit_zlib(data, z, &zp->zlib_init, CURLE_WRITE_ERROR); |
| } |
| |
| static void gzip_do_close(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zlib_writer *zp = (struct zlib_writer *) writer; |
| z_stream *z = &zp->z; /* zlib state structure */ |
| |
| exit_zlib(data, z, &zp->zlib_init, CURLE_OK); |
| } |
| |
| static const struct Curl_cwtype gzip_encoding = { |
| "gzip", |
| "x-gzip", |
| gzip_do_init, |
| gzip_do_write, |
| gzip_do_close, |
| sizeof(struct zlib_writer) |
| }; |
| |
| #endif /* HAVE_LIBZ */ |
| |
| #ifdef HAVE_BROTLI |
| /* Brotli writer. */ |
| struct brotli_writer { |
| struct Curl_cwriter super; |
| char buffer[DECOMPRESS_BUFFER_SIZE]; |
| BrotliDecoderState *br; /* State structure for brotli. */ |
| }; |
| |
| static CURLcode brotli_map_error(BrotliDecoderErrorCode be) |
| { |
| switch(be) { |
| case BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_NIBBLE: |
| case BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE: |
| case BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET: |
| case BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME: |
| case BROTLI_DECODER_ERROR_FORMAT_CL_SPACE: |
| case BROTLI_DECODER_ERROR_FORMAT_HUFFMAN_SPACE: |
| case BROTLI_DECODER_ERROR_FORMAT_CONTEXT_MAP_REPEAT: |
| case BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_1: |
| case BROTLI_DECODER_ERROR_FORMAT_BLOCK_LENGTH_2: |
| case BROTLI_DECODER_ERROR_FORMAT_TRANSFORM: |
| case BROTLI_DECODER_ERROR_FORMAT_DICTIONARY: |
| case BROTLI_DECODER_ERROR_FORMAT_WINDOW_BITS: |
| case BROTLI_DECODER_ERROR_FORMAT_PADDING_1: |
| case BROTLI_DECODER_ERROR_FORMAT_PADDING_2: |
| #ifdef BROTLI_DECODER_ERROR_COMPOUND_DICTIONARY |
| case BROTLI_DECODER_ERROR_COMPOUND_DICTIONARY: |
| #endif |
| #ifdef BROTLI_DECODER_ERROR_DICTIONARY_NOT_SET |
| case BROTLI_DECODER_ERROR_DICTIONARY_NOT_SET: |
| #endif |
| case BROTLI_DECODER_ERROR_INVALID_ARGUMENTS: |
| return CURLE_BAD_CONTENT_ENCODING; |
| case BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MODES: |
| case BROTLI_DECODER_ERROR_ALLOC_TREE_GROUPS: |
| case BROTLI_DECODER_ERROR_ALLOC_CONTEXT_MAP: |
| case BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_1: |
| case BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2: |
| case BROTLI_DECODER_ERROR_ALLOC_BLOCK_TYPE_TREES: |
| return CURLE_OUT_OF_MEMORY; |
| default: |
| break; |
| } |
| return CURLE_WRITE_ERROR; |
| } |
| |
| static CURLcode brotli_do_init(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct brotli_writer *bp = (struct brotli_writer *) writer; |
| (void)data; |
| |
| bp->br = BrotliDecoderCreateInstance(NULL, NULL, NULL); |
| return bp->br ? CURLE_OK : CURLE_OUT_OF_MEMORY; |
| } |
| |
| static CURLcode brotli_do_write(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| const char *buf, size_t nbytes) |
| { |
| struct brotli_writer *bp = (struct brotli_writer *) writer; |
| const uint8_t *src = (const uint8_t *) buf; |
| uint8_t *dst; |
| size_t dstleft; |
| CURLcode result = CURLE_OK; |
| BrotliDecoderResult r = BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT; |
| |
| if(!(type & CLIENTWRITE_BODY) || !nbytes) |
| return Curl_cwriter_write(data, writer->next, type, buf, nbytes); |
| |
| if(!bp->br) |
| return CURLE_WRITE_ERROR; /* Stream already ended. */ |
| |
| while((nbytes || r == BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT) && |
| result == CURLE_OK) { |
| dst = (uint8_t *) bp->buffer; |
| dstleft = DECOMPRESS_BUFFER_SIZE; |
| r = BrotliDecoderDecompressStream(bp->br, |
| &nbytes, &src, &dstleft, &dst, NULL); |
| result = Curl_cwriter_write(data, writer->next, type, |
| bp->buffer, DECOMPRESS_BUFFER_SIZE - dstleft); |
| if(result) |
| break; |
| switch(r) { |
| case BROTLI_DECODER_RESULT_NEEDS_MORE_OUTPUT: |
| case BROTLI_DECODER_RESULT_NEEDS_MORE_INPUT: |
| break; |
| case BROTLI_DECODER_RESULT_SUCCESS: |
| BrotliDecoderDestroyInstance(bp->br); |
| bp->br = NULL; |
| if(nbytes) |
| result = CURLE_WRITE_ERROR; |
| break; |
| default: |
| result = brotli_map_error(BrotliDecoderGetErrorCode(bp->br)); |
| break; |
| } |
| } |
| return result; |
| } |
| |
| static void brotli_do_close(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct brotli_writer *bp = (struct brotli_writer *) writer; |
| (void)data; |
| |
| if(bp->br) { |
| BrotliDecoderDestroyInstance(bp->br); |
| bp->br = NULL; |
| } |
| } |
| |
| static const struct Curl_cwtype brotli_encoding = { |
| "br", |
| NULL, |
| brotli_do_init, |
| brotli_do_write, |
| brotli_do_close, |
| sizeof(struct brotli_writer) |
| }; |
| #endif |
| |
| #ifdef HAVE_ZSTD |
| /* Zstd writer. */ |
| struct zstd_writer { |
| struct Curl_cwriter super; |
| ZSTD_DStream *zds; /* State structure for zstd. */ |
| char buffer[DECOMPRESS_BUFFER_SIZE]; |
| }; |
| |
| #ifdef ZSTD_STATIC_LINKING_ONLY |
| static void *Curl_zstd_alloc(void *opaque, size_t size) |
| { |
| (void)opaque; |
| return Curl_cmalloc(size); |
| } |
| |
| static void Curl_zstd_free(void *opaque, void *address) |
| { |
| (void)opaque; |
| Curl_cfree(address); |
| } |
| #endif |
| |
| static CURLcode zstd_do_init(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zstd_writer *zp = (struct zstd_writer *) writer; |
| |
| (void)data; |
| |
| #ifdef ZSTD_STATIC_LINKING_ONLY |
| zp->zds = ZSTD_createDStream_advanced((ZSTD_customMem) { |
| .customAlloc = Curl_zstd_alloc, |
| .customFree = Curl_zstd_free, |
| .opaque = NULL |
| }); |
| #else |
| zp->zds = ZSTD_createDStream(); |
| #endif |
| |
| return zp->zds ? CURLE_OK : CURLE_OUT_OF_MEMORY; |
| } |
| |
| static CURLcode zstd_do_write(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| const char *buf, size_t nbytes) |
| { |
| CURLcode result = CURLE_OK; |
| struct zstd_writer *zp = (struct zstd_writer *) writer; |
| ZSTD_inBuffer in; |
| ZSTD_outBuffer out; |
| size_t errorCode; |
| |
| if(!(type & CLIENTWRITE_BODY) || !nbytes) |
| return Curl_cwriter_write(data, writer->next, type, buf, nbytes); |
| |
| in.pos = 0; |
| in.src = buf; |
| in.size = nbytes; |
| |
| for(;;) { |
| out.pos = 0; |
| out.dst = zp->buffer; |
| out.size = DECOMPRESS_BUFFER_SIZE; |
| |
| errorCode = ZSTD_decompressStream(zp->zds, &out, &in); |
| if(ZSTD_isError(errorCode)) { |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| if(out.pos > 0) { |
| result = Curl_cwriter_write(data, writer->next, type, |
| zp->buffer, out.pos); |
| if(result) |
| break; |
| } |
| if((in.pos == nbytes) && (out.pos < out.size)) |
| break; |
| } |
| |
| return result; |
| } |
| |
| static void zstd_do_close(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| struct zstd_writer *zp = (struct zstd_writer *) writer; |
| (void)data; |
| |
| if(zp->zds) { |
| ZSTD_freeDStream(zp->zds); |
| zp->zds = NULL; |
| } |
| } |
| |
| static const struct Curl_cwtype zstd_encoding = { |
| "zstd", |
| NULL, |
| zstd_do_init, |
| zstd_do_write, |
| zstd_do_close, |
| sizeof(struct zstd_writer) |
| }; |
| #endif |
| |
| /* Identity handler. */ |
| static const struct Curl_cwtype identity_encoding = { |
| "identity", |
| "none", |
| Curl_cwriter_def_init, |
| Curl_cwriter_def_write, |
| Curl_cwriter_def_close, |
| sizeof(struct Curl_cwriter) |
| }; |
| |
| /* supported general content decoders. */ |
| static const struct Curl_cwtype * const general_unencoders[] = { |
| &identity_encoding, |
| #ifdef HAVE_LIBZ |
| &deflate_encoding, |
| &gzip_encoding, |
| #endif |
| #ifdef HAVE_BROTLI |
| &brotli_encoding, |
| #endif |
| #ifdef HAVE_ZSTD |
| &zstd_encoding, |
| #endif |
| NULL |
| }; |
| |
| /* supported content decoders only for transfer encodings */ |
| static const struct Curl_cwtype * const transfer_unencoders[] = { |
| #ifndef CURL_DISABLE_HTTP |
| &Curl_httpchunk_unencoder, |
| #endif |
| NULL |
| }; |
| |
| /* Provide a list of comma-separated names of supported encodings. |
| */ |
| void Curl_all_content_encodings(char *buf, size_t blen) |
| { |
| size_t len = 0; |
| const struct Curl_cwtype * const *cep; |
| const struct Curl_cwtype *ce; |
| |
| DEBUGASSERT(buf); |
| DEBUGASSERT(blen); |
| buf[0] = 0; |
| |
| for(cep = general_unencoders; *cep; cep++) { |
| ce = *cep; |
| if(!curl_strequal(ce->name, CONTENT_ENCODING_DEFAULT)) |
| len += strlen(ce->name) + 2; |
| } |
| |
| if(!len) { |
| if(blen >= sizeof(CONTENT_ENCODING_DEFAULT)) |
| strcpy(buf, CONTENT_ENCODING_DEFAULT); |
| } |
| else if(blen > len) { |
| char *p = buf; |
| for(cep = general_unencoders; *cep; cep++) { |
| ce = *cep; |
| if(!curl_strequal(ce->name, CONTENT_ENCODING_DEFAULT)) { |
| strcpy(p, ce->name); |
| p += strlen(p); |
| *p++ = ','; |
| *p++ = ' '; |
| } |
| } |
| p[-2] = '\0'; |
| } |
| } |
| |
| /* Deferred error dummy writer. */ |
| static CURLcode error_do_init(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| (void)data; |
| (void)writer; |
| return CURLE_OK; |
| } |
| |
| static CURLcode error_do_write(struct Curl_easy *data, |
| struct Curl_cwriter *writer, int type, |
| const char *buf, size_t nbytes) |
| { |
| (void)writer; |
| (void)buf; |
| (void)nbytes; |
| |
| if(!(type & CLIENTWRITE_BODY) || !nbytes) |
| return Curl_cwriter_write(data, writer->next, type, buf, nbytes); |
| else { |
| char all[256]; |
| (void)Curl_all_content_encodings(all, sizeof(all)); |
| failf(data, "Unrecognized content encoding type. " |
| "libcurl understands %s content encodings.", all); |
| } |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| |
| static void error_do_close(struct Curl_easy *data, |
| struct Curl_cwriter *writer) |
| { |
| (void)data; |
| (void)writer; |
| } |
| |
| static const struct Curl_cwtype error_writer = { |
| "ce-error", |
| NULL, |
| error_do_init, |
| error_do_write, |
| error_do_close, |
| sizeof(struct Curl_cwriter) |
| }; |
| |
| /* Find the content encoding by name. */ |
| static const struct Curl_cwtype *find_unencode_writer(const char *name, |
| size_t len, |
| Curl_cwriter_phase phase) |
| { |
| const struct Curl_cwtype * const *cep; |
| |
| if(phase == CURL_CW_TRANSFER_DECODE) { |
| for(cep = transfer_unencoders; *cep; cep++) { |
| const struct Curl_cwtype *ce = *cep; |
| if((curl_strnequal(name, ce->name, len) && !ce->name[len]) || |
| (ce->alias && curl_strnequal(name, ce->alias, len) |
| && !ce->alias[len])) |
| return ce; |
| } |
| } |
| /* look among the general decoders */ |
| for(cep = general_unencoders; *cep; cep++) { |
| const struct Curl_cwtype *ce = *cep; |
| if((curl_strnequal(name, ce->name, len) && !ce->name[len]) || |
| (ce->alias && curl_strnequal(name, ce->alias, len) && !ce->alias[len])) |
| return ce; |
| } |
| return NULL; |
| } |
| |
| /* Setup the unencoding stack from the Content-Encoding header value. |
| * See RFC 7231 section 3.1.2.2. */ |
| CURLcode Curl_build_unencoding_stack(struct Curl_easy *data, |
| const char *enclist, int is_transfer) |
| { |
| Curl_cwriter_phase phase = is_transfer ? |
| CURL_CW_TRANSFER_DECODE : CURL_CW_CONTENT_DECODE; |
| CURLcode result; |
| bool has_chunked = FALSE; |
| |
| do { |
| const char *name; |
| size_t namelen; |
| bool is_chunked = FALSE; |
| |
| /* Parse a single encoding name. */ |
| while(ISBLANK(*enclist) || *enclist == ',') |
| enclist++; |
| |
| name = enclist; |
| |
| for(namelen = 0; *enclist && *enclist != ','; enclist++) |
| if(*enclist > ' ') |
| namelen = enclist - name + 1; |
| |
| if(namelen) { |
| const struct Curl_cwtype *cwt; |
| struct Curl_cwriter *writer; |
| |
| CURL_TRC_WRITE(data, "looking for %s decoder: %.*s", |
| is_transfer ? "transfer" : "content", (int)namelen, name); |
| is_chunked = (is_transfer && (namelen == 7) && |
| curl_strnequal(name, "chunked", 7)); |
| /* if we skip the decoding in this phase, do not look further. |
| * Exception is "chunked" transfer-encoding which always must happen */ |
| if((is_transfer && !data->set.http_transfer_encoding && !is_chunked) || |
| (!is_transfer && data->set.http_ce_skip)) { |
| bool is_identity = curl_strnequal(name, "identity", 8); |
| /* not requested, ignore */ |
| CURL_TRC_WRITE(data, "decoder not requested, ignored: %.*s", |
| (int)namelen, name); |
| if(is_transfer && !data->set.http_te_skip) { |
| if(has_chunked) |
| failf(data, "A Transfer-Encoding (%.*s) was listed after chunked", |
| (int)namelen, name); |
| else if(is_identity) |
| continue; |
| else |
| failf(data, "Unsolicited Transfer-Encoding (%.*s) found", |
| (int)namelen, name); |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| return CURLE_OK; |
| } |
| |
| if(Curl_cwriter_count(data, phase) + 1 >= MAX_ENCODE_STACK) { |
| failf(data, "Reject response due to more than %u content encodings", |
| MAX_ENCODE_STACK); |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| |
| cwt = find_unencode_writer(name, namelen, phase); |
| if(cwt && is_chunked && Curl_cwriter_get_by_type(data, cwt)) { |
| /* A 'chunked' transfer encoding has already been added. |
| * Ignore duplicates. See #13451. |
| * Also RFC 9112, ch. 6.1: |
| * "A sender MUST NOT apply the chunked transfer coding more than |
| * once to a message body." |
| */ |
| CURL_TRC_WRITE(data, "ignoring duplicate 'chunked' decoder"); |
| return CURLE_OK; |
| } |
| |
| if(is_transfer && !is_chunked && |
| Curl_cwriter_get_by_name(data, "chunked")) { |
| /* RFC 9112, ch. 6.1: |
| * "If any transfer coding other than chunked is applied to a |
| * response's content, the sender MUST either apply chunked as the |
| * final transfer coding or terminate the message by closing the |
| * connection." |
| * "chunked" must be the last added to be the first in its phase, |
| * reject this. |
| */ |
| failf(data, "Reject response due to 'chunked' not being the last " |
| "Transfer-Encoding"); |
| return CURLE_BAD_CONTENT_ENCODING; |
| } |
| |
| if(!cwt) |
| cwt = &error_writer; /* Defer error at use. */ |
| |
| result = Curl_cwriter_create(&writer, data, cwt, phase); |
| CURL_TRC_WRITE(data, "added %s decoder %s -> %d", |
| is_transfer ? "transfer" : "content", cwt->name, result); |
| if(result) |
| return result; |
| |
| result = Curl_cwriter_add(data, writer); |
| if(result) { |
| Curl_cwriter_free(data, writer); |
| return result; |
| } |
| if(is_chunked) |
| has_chunked = TRUE; |
| } |
| } while(*enclist); |
| |
| return CURLE_OK; |
| } |
| |
| #else |
| /* Stubs for builds without HTTP. */ |
| CURLcode Curl_build_unencoding_stack(struct Curl_easy *data, |
| const char *enclist, int is_transfer) |
| { |
| (void)data; |
| (void)enclist; |
| (void)is_transfer; |
| return CURLE_NOT_BUILT_IN; |
| } |
| |
| void Curl_all_content_encodings(char *buf, size_t blen) |
| { |
| DEBUGASSERT(buf); |
| DEBUGASSERT(blen); |
| if(blen < sizeof(CONTENT_ENCODING_DEFAULT)) |
| buf[0] = 0; |
| else |
| strcpy(buf, CONTENT_ENCODING_DEFAULT); |
| } |
| |
| #endif /* CURL_DISABLE_HTTP */ |