/* 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.

 */

/*

 * Originally written @ Covalent by Jim Jagielski

 */

/*

 * mod_dumpio.c:

 *  Think of this as a filter sniffer for Apache 2.x. It logs

 *  all filter data right before and after it goes out on the

 *  wire (BUT right before SSL encoded or after SSL decoded).

 *  It can produce a *huge* amount of data.

 */

#include "httpd.h"

#include "http_connection.h"

#include "http_config.h"

#include "http_core.h"

#include "http_log.h"

#include "apr_strings.h"

module AP_MODULE_DECLARE_DATA dumpio_module ;

typedef struct dumpio_conf_t {

    int enable_input;

    int enable_output;

} dumpio_conf_t;

/* consider up to 80 additional characters, and factor the longest

 * line length of all \xNN sequences; log_error cannot record more

 * than MAX_STRING_LEN characters.

 */

#define dumpio_MAX_STRING_LEN (MAX_STRING_LEN / 4 - 80)

/*

 * Workhorse function: simply log to the current error_log

 * info about the data in the bucket as well as the data itself

 */

static void dumpit(ap_filter_t *f, apr_bucket *b, dumpio_conf_t *ptr)

{

    conn_rec *c = f->c;

    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,

                  "mod_dumpio:  %s (%s-%s): %" APR_SIZE_T_FMT " bytes",

                  f->frec->name,

                  (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",

                  b->type->name,

                  b->length) ;

    if (!(APR_BUCKET_IS_METADATA(b)))

    {

#if APR_CHARSET_EBCDIC

        char xlatebuf[dumpio_MAX_STRING_LEN + 1];

#endif

        const char *buf;

        apr_size_t nbytes;

        apr_status_t rv = apr_bucket_read(b, &buf, &nbytes, APR_BLOCK_READ);

        if (rv == APR_SUCCESS)

        {

            while (nbytes)

            {

                apr_size_t logbytes = nbytes;

                if (logbytes > dumpio_MAX_STRING_LEN)

                    logbytes = dumpio_MAX_STRING_LEN;

                nbytes -= logbytes;

#if APR_CHARSET_EBCDIC

                memcpy(xlatebuf, buf, logbytes);

                ap_xlate_proto_from_ascii(xlatebuf, logbytes);

                xlatebuf[logbytes] = '\0';

                ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,

                              "mod_dumpio:  %s (%s-%s): %s", f->frec->name,

                              (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",

                              b->type->name, xlatebuf);

#else

                /* XXX: Seriously flawed; we do not pay attention to embedded

                 * \0's in the request body, these should be escaped; however,

                 * the logging function already performs a significant amount

                 * of escaping, and so any escaping would be double-escaped.

                 * The coding solution is to throw away the current logic

                 * within ap_log_error, and introduce new vformatter %-escapes

                 * for escaping text, and for binary text (fixed len strings).

                 */

                ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,

                              "mod_dumpio:  %s (%s-%s): %.*s", f->frec->name,

                              (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",

                              b->type->name, (int)logbytes, buf);

#endif

                buf += logbytes;

            }

        }

        else {

            ap_log_cerror(APLOG_MARK, APLOG_TRACE7, rv, c,

                          "mod_dumpio:  %s (%s-%s): %s", f->frec->name,

                          (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",

                          b->type->name, "error reading data");

        }

    }

}

#define whichmode( mode ) \

 ( (( mode ) == AP_MODE_READBYTES) ? "readbytes" : \

   (( mode ) == AP_MODE_GETLINE) ? "getline" : \

   (( mode ) == AP_MODE_EATCRLF) ? "eatcrlf" : \

   (( mode ) == AP_MODE_SPECULATIVE) ? "speculative" : \

   (( mode ) == AP_MODE_EXHAUSTIVE) ? "exhaustive" : \

   (( mode ) == AP_MODE_INIT) ? "init" : "unknown" \

 )

static int dumpio_input_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 *b;

    apr_status_t ret;

    conn_rec *c = f->c;

    dumpio_conf_t *ptr = f->ctx;

    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,

                  "mod_dumpio: %s [%s-%s] %" APR_OFF_T_FMT " readbytes",

                  f->frec->name,

                  whichmode(mode),

                  ((block) == APR_BLOCK_READ) ? "blocking" : "nonblocking",

                  readbytes);

    ret = ap_get_brigade(f->next, bb, mode, block, readbytes);

    if (ret == APR_SUCCESS) {

        for (b = APR_BRIGADE_FIRST(bb); b != APR_BRIGADE_SENTINEL(bb); b = APR_BUCKET_NEXT(b)) {

          dumpit(f, b, ptr);

        }

    }

    else {

        ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,

                      "mod_dumpio: %s - %d", f->frec->name, ret) ;

        return ret;

    }

    return APR_SUCCESS ;

}

static int dumpio_output_filter (ap_filter_t *f, apr_bucket_brigade *bb)

{

    apr_bucket *b;

    conn_rec *c = f->c;

    dumpio_conf_t *ptr = f->ctx;

    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c, "mod_dumpio: %s", f->frec->name);

    for (b = APR_BRIGADE_FIRST(bb); b != APR_BRIGADE_SENTINEL(bb); b = APR_BUCKET_NEXT(b)) {

        /*

         * If we ever see an EOS, make sure to FLUSH.

         */

        if (APR_BUCKET_IS_EOS(b)) {

            apr_bucket *flush = apr_bucket_flush_create(f->c->bucket_alloc);

            APR_BUCKET_INSERT_BEFORE(b, flush);

        }

        dumpit(f, b, ptr);

    }

    return ap_pass_brigade(f->next, bb) ;

}

static int dumpio_pre_conn(conn_rec *c, void *csd)

{

    dumpio_conf_t *ptr;

    if (!APLOGctrace7(c)) {

        /* Nothing to do below TRACE7 */

        return DECLINED;

    }

    ptr = (dumpio_conf_t *) ap_get_module_config(c->base_server->module_config,

                                                 &dumpio_module);

    if (ptr->enable_input)

        ap_add_input_filter("DUMPIO_IN", ptr, NULL, c);

    if (ptr->enable_output)

        ap_add_output_filter("DUMPIO_OUT", ptr, NULL, c);

    return OK;

}

static void dumpio_register_hooks(apr_pool_t *p)

{

/*

 * We know that SSL is CONNECTION + 5

 */

  ap_register_output_filter("DUMPIO_OUT", dumpio_output_filter,

        NULL, AP_FTYPE_CONNECTION + 3) ;

  ap_register_input_filter("DUMPIO_IN", dumpio_input_filter,

        NULL, AP_FTYPE_CONNECTION + 3) ;

  ap_hook_pre_connection(dumpio_pre_conn, NULL, NULL, APR_HOOK_MIDDLE);

}

static void *dumpio_create_sconfig(apr_pool_t *p, server_rec *s)

{

    dumpio_conf_t *ptr = apr_pcalloc(p, sizeof *ptr);

    ptr->enable_input = 0;

    ptr->enable_output = 0;

    return ptr;

}

static const char *dumpio_enable_input(cmd_parms *cmd, void *dummy, int arg)

{

    dumpio_conf_t *ptr = ap_get_module_config(cmd->server->module_config,

                                              &dumpio_module);

    ptr->enable_input = arg;

    return NULL;

}

static const char *dumpio_enable_output(cmd_parms *cmd, void *dummy, int arg)

{

    dumpio_conf_t *ptr = ap_get_module_config(cmd->server->module_config,

                                              &dumpio_module);

    ptr->enable_output = arg;

    return NULL;

}

static const command_rec dumpio_cmds[] = {

    AP_INIT_FLAG("DumpIOInput", dumpio_enable_input, NULL,

                 RSRC_CONF, "Enable I/O Dump on Input Data"),

    AP_INIT_FLAG("DumpIOOutput", dumpio_enable_output, NULL,

                 RSRC_CONF, "Enable I/O Dump on Output Data"),

    { NULL }

};

AP_DECLARE_MODULE(dumpio) = {

        STANDARD20_MODULE_STUFF,

        NULL,                   /* create per-dir    config structures */

        NULL,                   /* merge  per-dir    config structures */

        dumpio_create_sconfig,  /* create per-server config structures */

        NULL,                   /* merge  per-server config structures */

        dumpio_cmds,            /* table of config file commands       */

        dumpio_register_hooks   /* register hooks                      */

};