diff options
Diffstat (limited to 'modules/filters/mod_deflate.c')
-rw-r--r-- | modules/filters/mod_deflate.c | 1123 |
1 files changed, 1123 insertions, 0 deletions
diff --git a/modules/filters/mod_deflate.c b/modules/filters/mod_deflate.c new file mode 100644 index 00000000..0924ea2f --- /dev/null +++ b/modules/filters/mod_deflate.c @@ -0,0 +1,1123 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/* + * mod_deflate.c: Perform deflate content-encoding on the fly + * + * Written by Ian Holsman, Justin Erenkrantz, and Nick Kew + */ + +/* + * Portions of this software are based upon zlib code by Jean-loup Gailly + * (zlib functions gz_open and gzwrite, check_header) + */ + +/* zlib flags */ +#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ +#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ +#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ +#define ORIG_NAME 0x08 /* bit 3 set: original file name present */ +#define COMMENT 0x10 /* bit 4 set: file comment present */ +#define RESERVED 0xE0 /* bits 5..7: reserved */ + + +#include "httpd.h" +#include "http_config.h" +#include "http_log.h" +#include "apr_strings.h" +#include "apr_general.h" +#include "util_filter.h" +#include "apr_buckets.h" +#include "http_request.h" +#define APR_WANT_STRFUNC +#include "apr_want.h" + +#include "zlib.h" + +static const char deflateFilterName[] = "DEFLATE"; +module AP_MODULE_DECLARE_DATA deflate_module; + +typedef struct deflate_filter_config_t +{ + int windowSize; + int memlevel; + int compressionlevel; + apr_size_t bufferSize; + char *note_ratio_name; + char *note_input_name; + char *note_output_name; +} deflate_filter_config; + +/* RFC 1952 Section 2.3 defines the gzip header: + * + * +---+---+---+---+---+---+---+---+---+---+ + * |ID1|ID2|CM |FLG| MTIME |XFL|OS | + * +---+---+---+---+---+---+---+---+---+---+ + */ +static const char gzip_header[10] = +{ '\037', '\213', Z_DEFLATED, 0, + 0, 0, 0, 0, /* mtime */ + 0, 0x03 /* Unix OS_CODE */ +}; + +/* magic header */ +static const char deflate_magic[2] = { '\037', '\213' }; + +/* windowsize is negative to suppress Zlib header */ +#define DEFAULT_COMPRESSION Z_DEFAULT_COMPRESSION +#define DEFAULT_WINDOWSIZE -15 +#define DEFAULT_MEMLEVEL 9 +#define DEFAULT_BUFFERSIZE 8096 + +/* Outputs a long in LSB order to the given file + * only the bottom 4 bits are required for the deflate file format. + */ +static void putLong(unsigned char *string, unsigned long x) +{ + string[0] = (unsigned char)(x & 0xff); + string[1] = (unsigned char)((x & 0xff00) >> 8); + string[2] = (unsigned char)((x & 0xff0000) >> 16); + string[3] = (unsigned char)((x & 0xff000000) >> 24); +} + +/* Inputs a string and returns a long. + */ +static unsigned long getLong(unsigned char *string) +{ + return ((unsigned long)string[0]) + | (((unsigned long)string[1]) << 8) + | (((unsigned long)string[2]) << 16) + | (((unsigned long)string[3]) << 24); +} + +static void *create_deflate_server_config(apr_pool_t *p, server_rec *s) +{ + deflate_filter_config *c = apr_pcalloc(p, sizeof *c); + + c->memlevel = DEFAULT_MEMLEVEL; + c->windowSize = DEFAULT_WINDOWSIZE; + c->bufferSize = DEFAULT_BUFFERSIZE; + c->compressionlevel = DEFAULT_COMPRESSION; + + return c; +} + +static const char *deflate_set_window_size(cmd_parms *cmd, void *dummy, + const char *arg) +{ + deflate_filter_config *c = ap_get_module_config(cmd->server->module_config, + &deflate_module); + int i; + + i = atoi(arg); + + if (i < 1 || i > 15) + return "DeflateWindowSize must be between 1 and 15"; + + c->windowSize = i * -1; + + return NULL; +} + +static const char *deflate_set_buffer_size(cmd_parms *cmd, void *dummy, + const char *arg) +{ + deflate_filter_config *c = ap_get_module_config(cmd->server->module_config, + &deflate_module); + int n = atoi(arg); + + if (n <= 0) { + return "DeflateBufferSize should be positive"; + } + + c->bufferSize = (apr_size_t)n; + + return NULL; +} +static const char *deflate_set_note(cmd_parms *cmd, void *dummy, + const char *arg1, const char *arg2) +{ + deflate_filter_config *c = ap_get_module_config(cmd->server->module_config, + &deflate_module); + + if (arg2 == NULL) { + c->note_ratio_name = apr_pstrdup(cmd->pool, arg1); + } + else if (!strcasecmp(arg1, "ratio")) { + c->note_ratio_name = apr_pstrdup(cmd->pool, arg2); + } + else if (!strcasecmp(arg1, "input")) { + c->note_input_name = apr_pstrdup(cmd->pool, arg2); + } + else if (!strcasecmp(arg1, "output")) { + c->note_output_name = apr_pstrdup(cmd->pool, arg2); + } + else { + return apr_psprintf(cmd->pool, "Unknown note type %s", arg1); + } + + return NULL; +} + +static const char *deflate_set_memlevel(cmd_parms *cmd, void *dummy, + const char *arg) +{ + deflate_filter_config *c = ap_get_module_config(cmd->server->module_config, + &deflate_module); + int i; + + i = atoi(arg); + + if (i < 1 || i > 9) + return "DeflateMemLevel must be between 1 and 9"; + + c->memlevel = i; + + return NULL; +} + +static const char *deflate_set_compressionlevel(cmd_parms *cmd, void *dummy, + const char *arg) +{ + deflate_filter_config *c = ap_get_module_config(cmd->server->module_config, + &deflate_module); + int i; + + i = atoi(arg); + + if (i < 1 || i > 9) + return "Compression Level must be between 1 and 9"; + + c->compressionlevel = i; + + return NULL; +} + +typedef struct deflate_ctx_t +{ + z_stream stream; + unsigned char *buffer; + unsigned long crc; + apr_bucket_brigade *bb, *proc_bb; +} deflate_ctx; + +static apr_status_t deflate_out_filter(ap_filter_t *f, + apr_bucket_brigade *bb) +{ + apr_bucket *e; + request_rec *r = f->r; + deflate_ctx *ctx = f->ctx; + int zRC; + deflate_filter_config *c = ap_get_module_config(r->server->module_config, + &deflate_module); + + /* Do nothing if asked to filter nothing. */ + if (APR_BRIGADE_EMPTY(bb)) { + return APR_SUCCESS; + } + + /* If we don't have a context, we need to ensure that it is okay to send + * the deflated content. If we have a context, that means we've done + * this before and we liked it. + * This could be not so nice if we always fail. But, if we succeed, + * we're in better shape. + */ + if (!ctx) { + char *token; + const char *encoding; + + /* only work on main request/no subrequests */ + if (r->main != NULL) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* some browsers might have problems, so set no-gzip + * (with browsermatch) for them + */ + if (apr_table_get(r->subprocess_env, "no-gzip")) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* Some browsers might have problems with content types + * other than text/html, so set gzip-only-text/html + * (with browsermatch) for them + */ + if (r->content_type == NULL + || strncmp(r->content_type, "text/html", 9)) { + const char *env_value = apr_table_get(r->subprocess_env, + "gzip-only-text/html"); + if ( env_value && (strcmp(env_value,"1") == 0) ) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + } + + /* Let's see what our current Content-Encoding is. + * If it's already encoded, don't compress again. + * (We could, but let's not.) + */ + encoding = apr_table_get(r->headers_out, "Content-Encoding"); + if (encoding) { + const char *err_enc; + + err_enc = apr_table_get(r->err_headers_out, "Content-Encoding"); + if (err_enc) { + encoding = apr_pstrcat(r->pool, encoding, ",", err_enc, NULL); + } + } + else { + encoding = apr_table_get(r->err_headers_out, "Content-Encoding"); + } + + if (r->content_encoding) { + encoding = encoding ? apr_pstrcat(r->pool, encoding, ",", + r->content_encoding, NULL) + : r->content_encoding; + } + + if (encoding) { + const char *tmp = encoding; + + token = ap_get_token(r->pool, &tmp, 0); + while (token && *token) { + /* stolen from mod_negotiation: */ + if (strcmp(token, "identity") && strcmp(token, "7bit") && + strcmp(token, "8bit") && strcmp(token, "binary")) { + + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* Otherwise, skip token */ + if (*tmp) { + ++tmp; + } + token = (*tmp) ? ap_get_token(r->pool, &tmp, 0) : NULL; + } + } + + /* Even if we don't accept this request based on it not having + * the Accept-Encoding, we need to note that we were looking + * for this header and downstream proxies should be aware of that. + */ + apr_table_mergen(r->headers_out, "Vary", "Accept-Encoding"); + + /* force-gzip will just force it out regardless if the browser + * can actually do anything with it. + */ + if (!apr_table_get(r->subprocess_env, "force-gzip")) { + const char *accepts; + /* if they don't have the line, then they can't play */ + accepts = apr_table_get(r->headers_in, "Accept-Encoding"); + if (accepts == NULL) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + token = ap_get_token(r->pool, &accepts, 0); + while (token && token[0] && strcasecmp(token, "gzip")) { + /* skip parameters, XXX: ;q=foo evaluation? */ + while (*accepts == ';') { + ++accepts; + token = ap_get_token(r->pool, &accepts, 1); + } + + /* retrieve next token */ + if (*accepts == ',') { + ++accepts; + } + token = (*accepts) ? ap_get_token(r->pool, &accepts, 0) : NULL; + } + + /* No acceptable token found. */ + if (token == NULL || token[0] == '\0') { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + } + + /* For a 304 or 204 response there is no entity included in + * the response and hence nothing to deflate. */ + if (r->status == HTTP_NOT_MODIFIED || r->status == HTTP_NO_CONTENT) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* We're cool with filtering this. */ + ctx = f->ctx = apr_pcalloc(r->pool, sizeof(*ctx)); + ctx->bb = apr_brigade_create(r->pool, f->c->bucket_alloc); + ctx->buffer = apr_palloc(r->pool, c->bufferSize); + + zRC = deflateInit2(&ctx->stream, c->compressionlevel, Z_DEFLATED, + c->windowSize, c->memlevel, + Z_DEFAULT_STRATEGY); + + if (zRC != Z_OK) { + f->ctx = NULL; + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "unable to init Zlib: " + "deflateInit2 returned %d: URL %s", + zRC, r->uri); + return ap_pass_brigade(f->next, bb); + } + + /* add immortal gzip header */ + e = apr_bucket_immortal_create(gzip_header, sizeof gzip_header, + f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, e); + + /* If the entire Content-Encoding is "identity", we can replace it. */ + if (!encoding || !strcasecmp(encoding, "identity")) { + apr_table_setn(r->headers_out, "Content-Encoding", "gzip"); + } + else { + apr_table_mergen(r->headers_out, "Content-Encoding", "gzip"); + } + apr_table_unset(r->headers_out, "Content-Length"); + + /* initialize deflate output buffer */ + ctx->stream.next_out = ctx->buffer; + ctx->stream.avail_out = c->bufferSize; + } + + while (!APR_BRIGADE_EMPTY(bb)) + { + const char *data; + apr_bucket *b; + apr_size_t len; + int done = 0; + + e = APR_BRIGADE_FIRST(bb); + + if (APR_BUCKET_IS_EOS(e)) { + char *buf; + unsigned int deflate_len; + + ctx->stream.avail_in = 0; /* should be zero already anyway */ + for (;;) { + deflate_len = c->bufferSize - ctx->stream.avail_out; + + if (deflate_len != 0) { + b = apr_bucket_heap_create((char *)ctx->buffer, + deflate_len, NULL, + f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, b); + ctx->stream.next_out = ctx->buffer; + ctx->stream.avail_out = c->bufferSize; + } + + if (done) { + break; + } + + zRC = deflate(&ctx->stream, Z_FINISH); + + if (deflate_len == 0 && zRC == Z_BUF_ERROR) { + zRC = Z_OK; + } + + done = (ctx->stream.avail_out != 0 || zRC == Z_STREAM_END); + + if (zRC != Z_OK && zRC != Z_STREAM_END) { + break; + } + } + + buf = apr_palloc(r->pool, 8); + putLong((unsigned char *)&buf[0], ctx->crc); + putLong((unsigned char *)&buf[4], ctx->stream.total_in); + + b = apr_bucket_pool_create(buf, 8, r->pool, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, b); + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, + "Zlib: Compressed %ld to %ld : URL %s", + ctx->stream.total_in, ctx->stream.total_out, r->uri); + + /* leave notes for logging */ + if (c->note_input_name) { + apr_table_setn(r->notes, c->note_input_name, + (ctx->stream.total_in > 0) + ? apr_off_t_toa(r->pool, + ctx->stream.total_in) + : "-"); + } + + if (c->note_output_name) { + apr_table_setn(r->notes, c->note_output_name, + (ctx->stream.total_in > 0) + ? apr_off_t_toa(r->pool, + ctx->stream.total_out) + : "-"); + } + + if (c->note_ratio_name) { + apr_table_setn(r->notes, c->note_ratio_name, + (ctx->stream.total_in > 0) + ? apr_itoa(r->pool, + (int)(ctx->stream.total_out + * 100 + / ctx->stream.total_in)) + : "-"); + } + + deflateEnd(&ctx->stream); + + /* Remove EOS from the old list, and insert into the new. */ + APR_BUCKET_REMOVE(e); + APR_BRIGADE_INSERT_TAIL(ctx->bb, e); + + /* Okay, we've seen the EOS. + * Time to pass it along down the chain. + */ + return ap_pass_brigade(f->next, ctx->bb); + } + + if (APR_BUCKET_IS_FLUSH(e)) { + apr_bucket *bkt; + apr_status_t rv; + + apr_bucket_delete(e); + + if (ctx->stream.avail_in > 0) { + zRC = deflate(&(ctx->stream), Z_SYNC_FLUSH); + if (zRC != Z_OK) { + return APR_EGENERAL; + } + } + + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + b = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, b); + ctx->stream.avail_out = c->bufferSize; + + bkt = apr_bucket_flush_create(f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, bkt); + rv = ap_pass_brigade(f->next, ctx->bb); + if (rv != APR_SUCCESS) { + return rv; + } + continue; + } + + /* read */ + apr_bucket_read(e, &data, &len, APR_BLOCK_READ); + + /* This crc32 function is from zlib. */ + ctx->crc = crc32(ctx->crc, (const Bytef *)data, len); + + /* write */ + ctx->stream.next_in = (unsigned char *)data; /* We just lost const-ness, + * but we'll just have to + * trust zlib */ + ctx->stream.avail_in = len; + + while (ctx->stream.avail_in != 0) { + if (ctx->stream.avail_out == 0) { + apr_status_t rv; + + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + b = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->bb, b); + ctx->stream.avail_out = c->bufferSize; + /* Send what we have right now to the next filter. */ + rv = ap_pass_brigade(f->next, ctx->bb); + if (rv != APR_SUCCESS) { + return rv; + } + } + + zRC = deflate(&(ctx->stream), Z_NO_FLUSH); + + if (zRC != Z_OK) + return APR_EGENERAL; + } + + apr_bucket_delete(e); + } + + apr_brigade_cleanup(bb); + return APR_SUCCESS; +} + +/* This is the deflate input filter (inflates). */ +static apr_status_t deflate_in_filter(ap_filter_t *f, + apr_bucket_brigade *bb, + ap_input_mode_t mode, + apr_read_type_e block, + apr_off_t readbytes) +{ + apr_bucket *bkt; + request_rec *r = f->r; + deflate_ctx *ctx = f->ctx; + int zRC; + apr_status_t rv; + deflate_filter_config *c; + + /* just get out of the way of things we don't want. */ + if (mode != AP_MODE_READBYTES) { + return ap_get_brigade(f->next, bb, mode, block, readbytes); + } + + c = ap_get_module_config(r->server->module_config, &deflate_module); + + if (!ctx) { + int found = 0; + char *token, deflate_hdr[10]; + const char *encoding; + apr_size_t len; + + /* only work on main request/no subrequests */ + if (!ap_is_initial_req(r)) { + ap_remove_input_filter(f); + return ap_get_brigade(f->next, bb, mode, block, readbytes); + } + + /* Let's see what our current Content-Encoding is. + * If gzip is present, don't gzip again. (We could, but let's not.) + */ + encoding = apr_table_get(r->headers_in, "Content-Encoding"); + if (encoding) { + const char *tmp = encoding; + + token = ap_get_token(r->pool, &tmp, 0); + while (token && token[0]) { + if (!strcasecmp(token, "gzip")) { + found = 1; + break; + } + /* Otherwise, skip token */ + tmp++; + token = ap_get_token(r->pool, &tmp, 0); + } + } + + if (found == 0) { + ap_remove_input_filter(f); + return ap_get_brigade(f->next, bb, mode, block, readbytes); + } + + f->ctx = ctx = apr_pcalloc(f->r->pool, sizeof(*ctx)); + ctx->bb = apr_brigade_create(r->pool, f->c->bucket_alloc); + ctx->proc_bb = apr_brigade_create(r->pool, f->c->bucket_alloc); + ctx->buffer = apr_palloc(r->pool, c->bufferSize); + + rv = ap_get_brigade(f->next, ctx->bb, AP_MODE_READBYTES, block, 10); + if (rv != APR_SUCCESS) { + return rv; + } + + len = 10; + rv = apr_brigade_flatten(ctx->bb, deflate_hdr, &len); + if (rv != APR_SUCCESS) { + return rv; + } + + /* We didn't get the magic bytes. */ + if (len != 10 || + deflate_hdr[0] != deflate_magic[0] || + deflate_hdr[1] != deflate_magic[1]) { + return APR_EGENERAL; + } + + /* We can't handle flags for now. */ + if (deflate_hdr[3] != 0) { + return APR_EGENERAL; + } + + zRC = inflateInit2(&ctx->stream, c->windowSize); + + if (zRC != Z_OK) { + f->ctx = NULL; + inflateEnd(&ctx->stream); + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "unable to init Zlib: " + "inflateInit2 returned %d: URL %s", + zRC, r->uri); + ap_remove_input_filter(f); + return ap_get_brigade(f->next, bb, mode, block, readbytes); + } + + /* initialize deflate output buffer */ + ctx->stream.next_out = ctx->buffer; + ctx->stream.avail_out = c->bufferSize; + + apr_brigade_cleanup(ctx->bb); + } + + if (APR_BRIGADE_EMPTY(ctx->proc_bb)) { + rv = ap_get_brigade(f->next, ctx->bb, mode, block, readbytes); + + if (rv != APR_SUCCESS) { + /* What about APR_EAGAIN errors? */ + inflateEnd(&ctx->stream); + return rv; + } + + for (bkt = APR_BRIGADE_FIRST(ctx->bb); + bkt != APR_BRIGADE_SENTINEL(ctx->bb); + bkt = APR_BUCKET_NEXT(bkt)) + { + const char *data; + apr_size_t len; + + /* If we actually see the EOS, that means we screwed up! */ + if (APR_BUCKET_IS_EOS(bkt)) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + + if (APR_BUCKET_IS_FLUSH(bkt)) { + apr_bucket *tmp_heap; + zRC = inflate(&(ctx->stream), Z_SYNC_FLUSH); + if (zRC != Z_OK) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + + /* Move everything to the returning brigade. */ + APR_BUCKET_REMOVE(bkt); + APR_BRIGADE_CONCAT(bb, ctx->bb); + break; + } + + /* read */ + apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ); + + /* pass through zlib inflate. */ + ctx->stream.next_in = (unsigned char *)data; + ctx->stream.avail_in = len; + + zRC = Z_OK; + + while (ctx->stream.avail_in != 0) { + if (ctx->stream.avail_out == 0) { + apr_bucket *tmp_heap; + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + } + + zRC = inflate(&ctx->stream, Z_NO_FLUSH); + + if (zRC == Z_STREAM_END) { + break; + } + + if (zRC != Z_OK) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + } + if (zRC == Z_STREAM_END) { + apr_bucket *tmp_heap, *eos; + + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, + "Zlib: Inflated %ld to %ld : URL %s", + ctx->stream.total_in, ctx->stream.total_out, + r->uri); + + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + + /* Is the remaining 8 bytes already in the avail stream? */ + if (ctx->stream.avail_in >= 8) { + unsigned long compCRC, compLen; + compCRC = getLong(ctx->stream.next_in); + if (ctx->crc != compCRC) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + ctx->stream.next_in += 4; + compLen = getLong(ctx->stream.next_in); + if (ctx->stream.total_out != compLen) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + } + else { + /* FIXME: We need to grab the 8 verification bytes + * from the wire! */ + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + + inflateEnd(&ctx->stream); + + eos = apr_bucket_eos_create(f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, eos); + break; + } + + } + apr_brigade_cleanup(ctx->bb); + } + + /* If we are about to return nothing for a 'blocking' read and we have + * some data in our zlib buffer, flush it out so we can return something. + */ + if (block == APR_BLOCK_READ && + APR_BRIGADE_EMPTY(ctx->proc_bb) && + ctx->stream.avail_out < c->bufferSize) { + apr_bucket *tmp_heap; + apr_size_t len; + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + } + + if (!APR_BRIGADE_EMPTY(ctx->proc_bb)) { + apr_bucket_brigade *newbb; + + /* May return APR_INCOMPLETE which is fine by us. */ + apr_brigade_partition(ctx->proc_bb, readbytes, &bkt); + + newbb = apr_brigade_split(ctx->proc_bb, bkt); + APR_BRIGADE_CONCAT(bb, ctx->proc_bb); + APR_BRIGADE_CONCAT(ctx->proc_bb, newbb); + } + + return APR_SUCCESS; +} + + +/* Filter to inflate for a content-transforming proxy. */ +static apr_status_t inflate_out_filter(ap_filter_t *f, + apr_bucket_brigade *bb) +{ + int zlib_method; + int zlib_flags; + int deflate_init = 1; + apr_bucket *bkt; + request_rec *r = f->r; + deflate_ctx *ctx = f->ctx; + int zRC; + apr_status_t rv; + deflate_filter_config *c; + + /* Do nothing if asked to filter nothing. */ + if (APR_BRIGADE_EMPTY(bb)) { + return APR_SUCCESS; + } + + c = ap_get_module_config(r->server->module_config, &deflate_module); + + if (!ctx) { + int found = 0; + char *token; + const char *encoding; + + /* only work on main request/no subrequests */ + if (!ap_is_initial_req(r)) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* Let's see what our current Content-Encoding is. + * If gzip is present, don't gzip again. (We could, but let's not.) + */ + encoding = apr_table_get(r->headers_out, "Content-Encoding"); + if (encoding) { + const char *tmp = encoding; + + token = ap_get_token(r->pool, &tmp, 0); + while (token && token[0]) { + if (!strcasecmp(token, "gzip")) { + found = 1; + break; + } + /* Otherwise, skip token */ + tmp++; + token = ap_get_token(r->pool, &tmp, 0); + } + } + + if (found == 0) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + apr_table_unset(r->headers_out, "Content-Encoding"); + + /* No need to inflate HEAD or 204/304 */ + if (APR_BUCKET_IS_EOS(APR_BRIGADE_FIRST(bb))) { + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + + f->ctx = ctx = apr_pcalloc(f->r->pool, sizeof(*ctx)); + ctx->proc_bb = apr_brigade_create(r->pool, f->c->bucket_alloc); + ctx->buffer = apr_palloc(r->pool, c->bufferSize); + + + zRC = inflateInit2(&ctx->stream, c->windowSize); + + if (zRC != Z_OK) { + f->ctx = NULL; + inflateEnd(&ctx->stream); + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "unable to init Zlib: " + "inflateInit2 returned %d: URL %s", + zRC, r->uri); + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + + /* initialize deflate output buffer */ + ctx->stream.next_out = ctx->buffer; + ctx->stream.avail_out = c->bufferSize; + + deflate_init = 0; + } + + for (bkt = APR_BRIGADE_FIRST(bb); + bkt != APR_BRIGADE_SENTINEL(bb); + bkt = APR_BUCKET_NEXT(bkt)) + { + const char *data; + apr_size_t len; + + /* If we actually see the EOS, that means we screwed up! */ + /* no it doesn't - not in a HEAD or 204/304 */ + if (APR_BUCKET_IS_EOS(bkt)) { + inflateEnd(&ctx->stream); + return ap_pass_brigade(f->next, bb); + } + + if (APR_BUCKET_IS_FLUSH(bkt)) { + apr_bucket *tmp_heap; + zRC = inflate(&(ctx->stream), Z_SYNC_FLUSH); + if (zRC != Z_OK) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "Inflate error %d on flush", zRC); + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + + /* Move everything to the returning brigade. */ + APR_BUCKET_REMOVE(bkt); + break; + } + + /* read */ + apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ); + + /* first bucket contains zlib header */ + if (!deflate_init++) { + if (len < 10) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "Insufficient data for inflate"); + return APR_EGENERAL; + } + else { + zlib_method = data[2]; + zlib_flags = data[3]; + if (zlib_method != Z_DEFLATED) { + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, + "inflate: data not deflated!"); + ap_remove_output_filter(f); + return ap_pass_brigade(f->next, bb); + } + if (data[0] != deflate_magic[0] || + data[1] != deflate_magic[1] || + (zlib_flags & RESERVED) != 0) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "inflate: bad header"); + return APR_EGENERAL ; + } + data += 10 ; + len -= 10 ; + } + if (zlib_flags & EXTRA_FIELD) { + unsigned int bytes = (unsigned int)(data[0]); + bytes += ((unsigned int)(data[1])) << 8; + bytes += 2; + if (len < bytes) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, + "inflate: extra field too big (not " + "supported)"); + return APR_EGENERAL; + } + data += bytes; + len -= bytes; + } + if (zlib_flags & ORIG_NAME) { + while (len-- && *data++); + } + if (zlib_flags & COMMENT) { + while (len-- && *data++); + } + if (zlib_flags & HEAD_CRC) { + len -= 2; + data += 2; + } + } + + /* pass through zlib inflate. */ + ctx->stream.next_in = (unsigned char *)data; + ctx->stream.avail_in = len; + + zRC = Z_OK; + + while (ctx->stream.avail_in != 0) { + if (ctx->stream.avail_out == 0) { + apr_bucket *tmp_heap; + ctx->stream.next_out = ctx->buffer; + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + } + + zRC = inflate(&ctx->stream, Z_NO_FLUSH); + + if (zRC == Z_STREAM_END) { + break; + } + + if (zRC != Z_OK) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + } + if (zRC == Z_STREAM_END) { + apr_bucket *tmp_heap, *eos; + + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, + "Zlib: Inflated %ld to %ld : URL %s", + ctx->stream.total_in, ctx->stream.total_out, + r->uri); + + len = c->bufferSize - ctx->stream.avail_out; + + ctx->crc = crc32(ctx->crc, (const Bytef *)ctx->buffer, len); + tmp_heap = apr_bucket_heap_create((char *)ctx->buffer, len, + NULL, f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, tmp_heap); + ctx->stream.avail_out = c->bufferSize; + + /* Is the remaining 8 bytes already in the avail stream? */ + if (ctx->stream.avail_in >= 8) { + unsigned long compCRC, compLen; + compCRC = getLong(ctx->stream.next_in); + if (ctx->crc != compCRC) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + ctx->stream.next_in += 4; + compLen = getLong(ctx->stream.next_in); + if (ctx->stream.total_out != compLen) { + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + } + else { + /* FIXME: We need to grab the 8 verification bytes + * from the wire! */ + inflateEnd(&ctx->stream); + return APR_EGENERAL; + } + + inflateEnd(&ctx->stream); + + eos = apr_bucket_eos_create(f->c->bucket_alloc); + APR_BRIGADE_INSERT_TAIL(ctx->proc_bb, eos); + break; + } + + } + + rv = ap_pass_brigade(f->next, ctx->proc_bb); + apr_brigade_cleanup(ctx->proc_bb); + return rv ; +} + +static void register_hooks(apr_pool_t *p) +{ + ap_register_output_filter(deflateFilterName, deflate_out_filter, NULL, + AP_FTYPE_CONTENT_SET); + ap_register_output_filter("INFLATE", inflate_out_filter, NULL, + AP_FTYPE_RESOURCE-1); + ap_register_input_filter(deflateFilterName, deflate_in_filter, NULL, + AP_FTYPE_CONTENT_SET); +} + +static const command_rec deflate_filter_cmds[] = { + AP_INIT_TAKE12("DeflateFilterNote", deflate_set_note, NULL, RSRC_CONF, + "Set a note to report on compression ratio"), + AP_INIT_TAKE1("DeflateWindowSize", deflate_set_window_size, NULL, + RSRC_CONF, "Set the Deflate window size (1-15)"), + AP_INIT_TAKE1("DeflateBufferSize", deflate_set_buffer_size, NULL, RSRC_CONF, + "Set the Deflate Buffer Size"), + AP_INIT_TAKE1("DeflateMemLevel", deflate_set_memlevel, NULL, RSRC_CONF, + "Set the Deflate Memory Level (1-9)"), + AP_INIT_TAKE1("DeflateCompressionLevel", deflate_set_compressionlevel, NULL, RSRC_CONF, + "Set the Deflate Compression Level (1-9)"), + {NULL} +}; + +module AP_MODULE_DECLARE_DATA deflate_module = { + STANDARD20_MODULE_STUFF, + NULL, /* dir config creater */ + NULL, /* dir merger --- default is to override */ + create_deflate_server_config, /* server config */ + NULL, /* merge server config */ + deflate_filter_cmds, /* command table */ + register_hooks /* register hooks */ +}; |