1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17/*
18 * Originally written @ Covalent by Jim Jagielski
19 */
20
21/*
22 * mod_dumpio.c:
23 *  Think of this as a filter sniffer for Apache 2.x. It logs
24 *  all filter data right before and after it goes out on the
25 *  wire (BUT right before SSL encoded or after SSL decoded).
26 *  It can produce a *huge* amount of data.
27 */
28
29
30#include "httpd.h"
31#include "http_connection.h"
32#include "http_config.h"
33#include "http_core.h"
34#include "http_log.h"
35#include "apr_strings.h"
36
37module AP_MODULE_DECLARE_DATA dumpio_module ;
38
39typedef struct dumpio_conf_t {
40    int enable_input;
41    int enable_output;
42} dumpio_conf_t;
43
44/* consider up to 80 additional characters, and factor the longest
45 * line length of all \xNN sequences; log_error cannot record more
46 * than MAX_STRING_LEN characters.
47 */
48#define dumpio_MAX_STRING_LEN (MAX_STRING_LEN / 4 - 80)
49
50/*
51 * Workhorse function: simply log to the current error_log
52 * info about the data in the bucket as well as the data itself
53 */
54static void dumpit(ap_filter_t *f, apr_bucket *b, dumpio_conf_t *ptr)
55{
56    conn_rec *c = f->c;
57
58    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,
59                  "mod_dumpio:  %s (%s-%s): %" APR_SIZE_T_FMT " bytes",
60                  f->frec->name,
61                  (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",
62                  b->type->name,
63                  b->length) ;
64
65    if (!(APR_BUCKET_IS_METADATA(b)))
66    {
67#if APR_CHARSET_EBCDIC
68        char xlatebuf[dumpio_MAX_STRING_LEN + 1];
69#endif
70        const char *buf;
71        apr_size_t nbytes;
72        apr_status_t rv = apr_bucket_read(b, &buf, &nbytes, APR_BLOCK_READ);
73
74        if (rv == APR_SUCCESS)
75        {
76            while (nbytes)
77            {
78                apr_size_t logbytes = nbytes;
79                if (logbytes > dumpio_MAX_STRING_LEN)
80                    logbytes = dumpio_MAX_STRING_LEN;
81                nbytes -= logbytes;
82
83#if APR_CHARSET_EBCDIC
84                memcpy(xlatebuf, buf, logbytes);
85                ap_xlate_proto_from_ascii(xlatebuf, logbytes);
86                xlatebuf[logbytes] = '\0';
87                ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,
88                              "mod_dumpio:  %s (%s-%s): %s", f->frec->name,
89                              (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",
90                              b->type->name, xlatebuf);
91#else
92                /* XXX: Seriously flawed; we do not pay attention to embedded
93                 * \0's in the request body, these should be escaped; however,
94                 * the logging function already performs a significant amount
95                 * of escaping, and so any escaping would be double-escaped.
96                 * The coding solution is to throw away the current logic
97                 * within ap_log_error, and introduce new vformatter %-escapes
98                 * for escaping text, and for binary text (fixed len strings).
99                 */
100                ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,
101                              "mod_dumpio:  %s (%s-%s): %.*s", f->frec->name,
102                              (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",
103                              b->type->name, (int)logbytes, buf);
104#endif
105                buf += logbytes;
106            }
107        }
108        else {
109            ap_log_cerror(APLOG_MARK, APLOG_TRACE7, rv, c,
110                          "mod_dumpio:  %s (%s-%s): %s", f->frec->name,
111                          (APR_BUCKET_IS_METADATA(b)) ? "metadata" : "data",
112                          b->type->name, "error reading data");
113        }
114    }
115}
116
117#define whichmode( mode ) \
118 ( (( mode ) == AP_MODE_READBYTES) ? "readbytes" : \
119   (( mode ) == AP_MODE_GETLINE) ? "getline" : \
120   (( mode ) == AP_MODE_EATCRLF) ? "eatcrlf" : \
121   (( mode ) == AP_MODE_SPECULATIVE) ? "speculative" : \
122   (( mode ) == AP_MODE_EXHAUSTIVE) ? "exhaustive" : \
123   (( mode ) == AP_MODE_INIT) ? "init" : "unknown" \
124 )
125
126static int dumpio_input_filter (ap_filter_t *f, apr_bucket_brigade *bb,
127    ap_input_mode_t mode, apr_read_type_e block, apr_off_t readbytes)
128{
129
130    apr_bucket *b;
131    apr_status_t ret;
132    conn_rec *c = f->c;
133    dumpio_conf_t *ptr = f->ctx;
134
135    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,
136                  "mod_dumpio: %s [%s-%s] %" APR_OFF_T_FMT " readbytes",
137                  f->frec->name,
138                  whichmode(mode),
139                  ((block) == APR_BLOCK_READ) ? "blocking" : "nonblocking",
140                  readbytes);
141
142    ret = ap_get_brigade(f->next, bb, mode, block, readbytes);
143
144    if (ret == APR_SUCCESS) {
145        for (b = APR_BRIGADE_FIRST(bb); b != APR_BRIGADE_SENTINEL(bb); b = APR_BUCKET_NEXT(b)) {
146          dumpit(f, b, ptr);
147        }
148    }
149    else {
150        ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c,
151                      "mod_dumpio: %s - %d", f->frec->name, ret) ;
152        return ret;
153    }
154
155    return APR_SUCCESS ;
156}
157
158static int dumpio_output_filter (ap_filter_t *f, apr_bucket_brigade *bb)
159{
160    apr_bucket *b;
161    conn_rec *c = f->c;
162    dumpio_conf_t *ptr = f->ctx;
163
164    ap_log_cerror(APLOG_MARK, APLOG_TRACE7, 0, c, "mod_dumpio: %s", f->frec->name);
165
166    for (b = APR_BRIGADE_FIRST(bb); b != APR_BRIGADE_SENTINEL(bb); b = APR_BUCKET_NEXT(b)) {
167        /*
168         * If we ever see an EOS, make sure to FLUSH.
169         */
170        if (APR_BUCKET_IS_EOS(b)) {
171            apr_bucket *flush = apr_bucket_flush_create(f->c->bucket_alloc);
172            APR_BUCKET_INSERT_BEFORE(b, flush);
173        }
174        dumpit(f, b, ptr);
175    }
176
177    return ap_pass_brigade(f->next, bb) ;
178}
179
180static int dumpio_pre_conn(conn_rec *c, void *csd)
181{
182    dumpio_conf_t *ptr;
183
184    ptr = (dumpio_conf_t *) ap_get_module_config(c->base_server->module_config,
185                                                 &dumpio_module);
186
187    if (ptr->enable_input)
188        ap_add_input_filter("DUMPIO_IN", ptr, NULL, c);
189    if (ptr->enable_output)
190        ap_add_output_filter("DUMPIO_OUT", ptr, NULL, c);
191    return OK;
192}
193
194static void dumpio_register_hooks(apr_pool_t *p)
195{
196/*
197 * We know that SSL is CONNECTION + 5
198 */
199  ap_register_output_filter("DUMPIO_OUT", dumpio_output_filter,
200        NULL, AP_FTYPE_CONNECTION + 3) ;
201
202  ap_register_input_filter("DUMPIO_IN", dumpio_input_filter,
203        NULL, AP_FTYPE_CONNECTION + 3) ;
204
205  ap_hook_pre_connection(dumpio_pre_conn, NULL, NULL, APR_HOOK_MIDDLE);
206}
207
208static void *dumpio_create_sconfig(apr_pool_t *p, server_rec *s)
209{
210    dumpio_conf_t *ptr = apr_pcalloc(p, sizeof *ptr);
211    ptr->enable_input = 0;
212    ptr->enable_output = 0;
213    return ptr;
214}
215
216static const char *dumpio_enable_input(cmd_parms *cmd, void *dummy, int arg)
217{
218    dumpio_conf_t *ptr = ap_get_module_config(cmd->server->module_config,
219                                              &dumpio_module);
220
221    ptr->enable_input = arg;
222    return NULL;
223}
224
225static const char *dumpio_enable_output(cmd_parms *cmd, void *dummy, int arg)
226{
227    dumpio_conf_t *ptr = ap_get_module_config(cmd->server->module_config,
228                                              &dumpio_module);
229
230    ptr->enable_output = arg;
231    return NULL;
232}
233
234static const command_rec dumpio_cmds[] = {
235    AP_INIT_FLAG("DumpIOInput", dumpio_enable_input, NULL,
236                 RSRC_CONF, "Enable I/O Dump on Input Data"),
237    AP_INIT_FLAG("DumpIOOutput", dumpio_enable_output, NULL,
238                 RSRC_CONF, "Enable I/O Dump on Output Data"),
239    { NULL }
240};
241
242AP_DECLARE_MODULE(dumpio) = {
243        STANDARD20_MODULE_STUFF,
244        NULL,                   /* create per-dir    config structures */
245        NULL,                   /* merge  per-dir    config structures */
246        dumpio_create_sconfig,  /* create per-server config structures */
247        NULL,                   /* merge  per-server config structures */
248        dumpio_cmds,            /* table of config file commands       */
249        dumpio_register_hooks   /* register hooks                      */
250};
251