/src/curl/lib/gopher.c

Source
/***************************************************************************
 *                                  _   _ ____  _
 *  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 "gopher.h"

#ifndef CURL_DISABLE_GOPHER

#include "transfer.h"
#include "sendf.h"
#include "curl_trc.h"
#include "cfilters.h"
#include "connect.h"
#include "select.h"
#include "url.h"
#include "escape.h"

#ifdef USE_SSL
static CURLcode gopher_connect(struct Curl_easy *data, bool *done)
{
  (void)data;
  (void)done;
  return CURLE_OK;
}

static CURLcode gopher_connecting(struct Curl_easy *data, bool *done)
{
  struct connectdata *conn = data->conn;
  CURLcode result;

  result = Curl_conn_connect(data, FIRSTSOCKET, TRUE, done);
  if(result)
    connclose(conn);
  *done = TRUE;
  return result;
}
#endif

static CURLcode gopher_do(struct Curl_easy *data, bool *done)
{
  CURLcode result = CURLE_OK;
  struct connectdata *conn = data->conn;
  curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
  char *gopherpath;
  const char *path = data->state.up.path;
  const char *query = data->state.up.query;
  const char *buf = NULL;
  char *buf_alloc = NULL;
  size_t nwritten, buf_len;
  timediff_t timeout_ms;
  int what;

  *done = TRUE; /* unconditionally */

  /* path is guaranteed non-NULL */
  DEBUGASSERT(path);

  if(query)
    gopherpath = curl_maprintf("%s?%s", path, query);
  else
    gopherpath = curlx_strdup(path);

  if(!gopherpath)
    return CURLE_OUT_OF_MEMORY;

  /* Create selector. Degenerate cases: / and /1 => convert to "" */
  if(strlen(gopherpath) <= 2) {
    buf = "";
    buf_len = 0;
    curlx_free(gopherpath);
  }
  else {
    const char *newp;

    /* Otherwise, drop / and the first character (i.e., item type) ... */
    newp = gopherpath;
    newp += 2;

    /* ... and finally unescape */
    result = Curl_urldecode(newp, 0, &buf_alloc, &buf_len, REJECT_ZERO);
    curlx_free(gopherpath);
    if(result)
      return result;
    buf = buf_alloc;

    /* A decoded CR or LF would terminate the single-line gopher request and
       let a crafted URL smuggle additional bytes onto the wire. REJECT_ZERO
       only blocks NUL; reject CR and LF here too. A TAB is left alone as it
       is the legitimate gopher type-7 selector/search separator. */
    if(memchr(buf, '\r', buf_len) || memchr(buf, '\n', buf_len)) {
      curlx_free(buf_alloc);
      failf(data, "Bad gopher selector, CR or LF not allowed");
      return CURLE_URL_MALFORMAT;
    }
  }

  for(; buf_len;) {

    result = Curl_xfer_send(data, buf, buf_len, FALSE, &nwritten);
    if(!result) { /* Which may not have written it all! */
      result = Curl_client_write(data, CLIENTWRITE_HEADER, buf, nwritten);
      if(result)
        break;

      if(nwritten > buf_len) {
        DEBUGASSERT(0);
        break;
      }
      buf_len -= nwritten;
      buf += nwritten;
      if(!buf_len)
        break; /* but it did write it all */
    }
    else
      break;

    timeout_ms = Curl_timeleft_ms(data);
    if(timeout_ms < 0) {
      result = CURLE_OPERATION_TIMEDOUT;
      break;
    }
    if(!timeout_ms)
      timeout_ms = TIMEDIFF_T_MAX;

    /* Do not busyloop. The entire loop thing is a workaround as it causes a
       BLOCKING behavior which is a NO-NO. This function should rather be
       split up in a do and a doing piece where the pieces that are not
       possible to send now will be sent in the doing function repeatedly
       until the entire request is sent. */
    what = SOCKET_WRITABLE(sockfd, timeout_ms);
    if(what < 0) {
      result = CURLE_SEND_ERROR;
      break;
    }
    else if(!what) {
      result = CURLE_OPERATION_TIMEDOUT;
      break;
    }
  }

  curlx_free(buf_alloc);

  if(!result)
    result = Curl_xfer_send(data, "\r\n", 2, FALSE, &nwritten);
  if(result) {
    failf(data, "Failed sending Gopher request");
    return result;
  }
  result = Curl_client_write(data, CLIENTWRITE_HEADER, "\r\n", 2);
  if(result)
    return result;

  Curl_xfer_setup_recv(data, FIRSTSOCKET, -1);
  return CURLE_OK;
}

/*
 * Gopher protocol handler.
 * This is also a nice simple template to build off for simple
 * connect-command-download protocols.
 */

const struct Curl_protocol Curl_protocol_gopher = {
  ZERO_NULL,                            /* setup_connection */
  gopher_do,                            /* do_it */
  ZERO_NULL,                            /* done */
  ZERO_NULL,                            /* do_more */
  ZERO_NULL,                            /* connect_it */
  ZERO_NULL,                            /* connecting */
  ZERO_NULL,                            /* doing */
  ZERO_NULL,                            /* proto_pollset */
  ZERO_NULL,                            /* doing_pollset */
  ZERO_NULL,                            /* domore_pollset */
  ZERO_NULL,                            /* perform_pollset */
  ZERO_NULL,                            /* disconnect */
  ZERO_NULL,                            /* write_resp */
  ZERO_NULL,                            /* write_resp_hd */
  ZERO_NULL,                            /* connection_is_dead */
  ZERO_NULL,                            /* attach connection */
  ZERO_NULL,                            /* follow */
};

#ifdef USE_SSL
const struct Curl_protocol Curl_protocol_gophers = {
  ZERO_NULL,                            /* setup_connection */
  gopher_do,                            /* do_it */
  ZERO_NULL,                            /* done */
  ZERO_NULL,                            /* do_more */
  gopher_connect,                       /* connect_it */
  gopher_connecting,                    /* connecting */
  ZERO_NULL,                            /* doing */
  ZERO_NULL,                            /* proto_pollset */
  ZERO_NULL,                            /* doing_pollset */
  ZERO_NULL,                            /* domore_pollset */
  ZERO_NULL,                            /* perform_pollset */
  ZERO_NULL,                            /* disconnect */
  ZERO_NULL,                            /* write_resp */
  ZERO_NULL,                            /* write_resp_hd */
  ZERO_NULL,                            /* connection_is_dead */
  ZERO_NULL,                            /* attach connection */
  ZERO_NULL,                            /* follow */
};
#endif

#endif /* CURL_DISABLE_GOPHER */

Coverage Report

Created: 2026-08-13 07:42

Line	Count	Source
1		/***************************************************************************
2		* _ _ ____ _
3		* Project ___\| \| \| \| _ \\| \|
4		* / __\| \| \| \| \|_) \| \|
5		* \| (__\| \|_\| \| _ <\| \|___
6		* \___\|\___/\|_\| \_\_____\|
7		*
8		* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9		*
10		* This software is licensed as described in the file COPYING, which
11		* you should have received as part of this distribution. The terms
12		* are also available at https://curl.se/docs/copyright.html.
13		*
14		* You may opt to use, copy, modify, merge, publish, distribute and/or sell
15		* copies of the Software, and permit persons to whom the Software is
16		* furnished to do so, under the terms of the COPYING file.
17		*
18		* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19		* KIND, either express or implied.
20		*
21		* SPDX-License-Identifier: curl
22		*
23		***************************************************************************/
24		#include "curl_setup.h"
25		#include "urldata.h"
26		#include "gopher.h"
27
28		#ifndef CURL_DISABLE_GOPHER
29
30		#include "transfer.h"
31		#include "sendf.h"
32		#include "curl_trc.h"
33		#include "cfilters.h"
34		#include "connect.h"
35		#include "select.h"
36		#include "url.h"
37		#include "escape.h"
38
39		#ifdef USE_SSL
40		static CURLcode gopher_connect(struct Curl_easy data, bool done)
41	0	{
42	0	(void)data;
43	0	(void)done;
44	0	return CURLE_OK;
45	0	}
46
47		static CURLcode gopher_connecting(struct Curl_easy data, bool done)
48	0	{
49	0	struct connectdata *conn = data->conn;
50	0	CURLcode result;
51
52	0	result = Curl_conn_connect(data, FIRSTSOCKET, TRUE, done);
53	0	if(result)
54	0	connclose(conn);
55	0	*done = TRUE;
56	0	return result;
57	0	}
58		#endif
59
60		static CURLcode gopher_do(struct Curl_easy data, bool done)
61	915	{
62	915	CURLcode result = CURLE_OK;
63	915	struct connectdata *conn = data->conn;
64	915	curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
65	915	char *gopherpath;
66	915	const char *path = data->state.up.path;
67	915	const char *query = data->state.up.query;
68	915	const char *buf = NULL;
69	915	char *buf_alloc = NULL;
70	915	size_t nwritten, buf_len;
71	915	timediff_t timeout_ms;
72	915	int what;
73
74	915	done = TRUE; / unconditionally */
75
76		/* path is guaranteed non-NULL */
77	915	DEBUGASSERT(path);
78
79	915	if(query)
80	37	gopherpath = curl_maprintf("%s?%s", path, query);
81	878	else
82	878	gopherpath = curlx_strdup(path);
83
84	915	if(!gopherpath)
85	0	return CURLE_OUT_OF_MEMORY;
86
87		/* Create selector. Degenerate cases: / and /1 => convert to "" */
88	915	if(strlen(gopherpath) <= 2) {
89	801	buf = "";
90	801	buf_len = 0;
91	801	curlx_free(gopherpath);
92	801	}
93	114	else {
94	114	const char *newp;
95
96		/* Otherwise, drop / and the first character (i.e., item type) ... */
97	114	newp = gopherpath;
98	114	newp += 2;
99
100		/* ... and finally unescape */
101	114	result = Curl_urldecode(newp, 0, &buf_alloc, &buf_len, REJECT_ZERO);
102	114	curlx_free(gopherpath);
103	114	if(result)
104	1	return result;
105	113	buf = buf_alloc;
106
107		/* A decoded CR or LF would terminate the single-line gopher request and
108		let a crafted URL smuggle additional bytes onto the wire. REJECT_ZERO
109		only blocks NUL; reject CR and LF here too. A TAB is left alone as it
110		is the legitimate gopher type-7 selector/search separator. */
111	113	if(memchr(buf, '\r', buf_len) \|\| memchr(buf, '\n', buf_len)) {
112	4	curlx_free(buf_alloc);
113	4	failf(data, "Bad gopher selector, CR or LF not allowed");
114	4	return CURLE_URL_MALFORMAT;
115	4	}
116	113	}
117
118	910	for(; buf_len;) {
119
120	109	result = Curl_xfer_send(data, buf, buf_len, FALSE, &nwritten);
121	109	if(!result) { /* Which may not have written it all! */
122	109	result = Curl_client_write(data, CLIENTWRITE_HEADER, buf, nwritten);
123	109	if(result)
124	1	break;
125
126	108	if(nwritten > buf_len) {
127	0	DEBUGASSERT(0);
128	0	break;
129	0	}
130	108	buf_len -= nwritten;
131	108	buf += nwritten;
132	108	if(!buf_len)
133	67	break; /* but it did write it all */
134	108	}
135	0	else
136	0	break;
137
138	41	timeout_ms = Curl_timeleft_ms(data);
139	41	if(timeout_ms < 0) {
140	0	result = CURLE_OPERATION_TIMEDOUT;
141	0	break;
142	0	}
143	41	if(!timeout_ms)
144	0	timeout_ms = TIMEDIFF_T_MAX;
145
146		/* Do not busyloop. The entire loop thing is a workaround as it causes a
147		BLOCKING behavior which is a NO-NO. This function should rather be
148		split up in a do and a doing piece where the pieces that are not
149		possible to send now will be sent in the doing function repeatedly
150		until the entire request is sent. */
151	41	what = SOCKET_WRITABLE(sockfd, timeout_ms);
152	41	if(what < 0) {
153	0	result = CURLE_SEND_ERROR;
154	0	break;
155	0	}
156	41	else if(!what) {
157	41	result = CURLE_OPERATION_TIMEDOUT;
158	41	break;
159	41	}
160	41	}
161
162	910	curlx_free(buf_alloc);
163
164	910	if(!result)
165	868	result = Curl_xfer_send(data, "\r\n", 2, FALSE, &nwritten);
166	910	if(result) {
167	42	failf(data, "Failed sending Gopher request");
168	42	return result;
169	42	}
170	868	result = Curl_client_write(data, CLIENTWRITE_HEADER, "\r\n", 2);
171	868	if(result)
172	2	return result;
173
174	866	Curl_xfer_setup_recv(data, FIRSTSOCKET, -1);
175	866	return CURLE_OK;
176	868	}
177
178		/*
179		* Gopher protocol handler.
180		* This is also a nice simple template to build off for simple
181		* connect-command-download protocols.
182		*/
183
184		const struct Curl_protocol Curl_protocol_gopher = {
185		ZERO_NULL, /* setup_connection */
186		gopher_do, /* do_it */
187		ZERO_NULL, /* done */
188		ZERO_NULL, /* do_more */
189		ZERO_NULL, /* connect_it */
190		ZERO_NULL, /* connecting */
191		ZERO_NULL, /* doing */
192		ZERO_NULL, /* proto_pollset */
193		ZERO_NULL, /* doing_pollset */
194		ZERO_NULL, /* domore_pollset */
195		ZERO_NULL, /* perform_pollset */
196		ZERO_NULL, /* disconnect */
197		ZERO_NULL, /* write_resp */
198		ZERO_NULL, /* write_resp_hd */
199		ZERO_NULL, /* connection_is_dead */
200		ZERO_NULL, /* attach connection */
201		ZERO_NULL, /* follow */
202		};
203
204		#ifdef USE_SSL
205		const struct Curl_protocol Curl_protocol_gophers = {
206		ZERO_NULL, /* setup_connection */
207		gopher_do, /* do_it */
208		ZERO_NULL, /* done */
209		ZERO_NULL, /* do_more */
210		gopher_connect, /* connect_it */
211		gopher_connecting, /* connecting */
212		ZERO_NULL, /* doing */
213		ZERO_NULL, /* proto_pollset */
214		ZERO_NULL, /* doing_pollset */
215		ZERO_NULL, /* domore_pollset */
216		ZERO_NULL, /* perform_pollset */
217		ZERO_NULL, /* disconnect */
218		ZERO_NULL, /* write_resp */
219		ZERO_NULL, /* write_resp_hd */
220		ZERO_NULL, /* connection_is_dead */
221		ZERO_NULL, /* attach connection */
222		ZERO_NULL, /* follow */
223		};
224		#endif
225
226		#endif /* CURL_DISABLE_GOPHER */