1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2022, Daniel Stenberg, <[email protected]>, 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
25#include "curl_setup.h"
26
27#ifndef CURL_DISABLE_GOPHER
28
29#include "urldata.h"
30#include <curl/curl.h>
31#include "transfer.h"
32#include "sendf.h"
33#include "connect.h"
34#include "progress.h"
35#include "gopher.h"
36#include "select.h"
37#include "strdup.h"
38#include "vtls/vtls.h"
39#include "url.h"
40#include "escape.h"
41#include "warnless.h"
42#include "curl_printf.h"
43#include "curl_memory.h"
44/* The last #include file should be: */
45#include "memdebug.h"
46
47/*
48 * Forward declarations.
49 */
50
51static CURLcode gopher_do(struct Curl_easy *data, bool *done);
52#ifdef USE_SSL
53static CURLcode gopher_connect(struct Curl_easy *data, bool *done);
54static CURLcode gopher_connecting(struct Curl_easy *data, bool *done);
55#endif
56
57/*
58 * Gopher protocol handler.
59 * This is also a nice simple template to build off for simple
60 * connect-command-download protocols.
61 */
62
63const struct Curl_handler Curl_handler_gopher = {
64 "GOPHER", /* scheme */
65 ZERO_NULL, /* setup_connection */
66 gopher_do, /* do_it */
67 ZERO_NULL, /* done */
68 ZERO_NULL, /* do_more */
69 ZERO_NULL, /* connect_it */
70 ZERO_NULL, /* connecting */
71 ZERO_NULL, /* doing */
72 ZERO_NULL, /* proto_getsock */
73 ZERO_NULL, /* doing_getsock */
74 ZERO_NULL, /* domore_getsock */
75 ZERO_NULL, /* perform_getsock */
76 ZERO_NULL, /* disconnect */
77 ZERO_NULL, /* readwrite */
78 ZERO_NULL, /* connection_check */
79 ZERO_NULL, /* attach connection */
80 PORT_GOPHER, /* defport */
81 CURLPROTO_GOPHER, /* protocol */
82 CURLPROTO_GOPHER, /* family */
83 PROTOPT_NONE /* flags */
84};
85
86#ifdef USE_SSL
87const struct Curl_handler Curl_handler_gophers = {
88 "GOPHERS", /* scheme */
89 ZERO_NULL, /* setup_connection */
90 gopher_do, /* do_it */
91 ZERO_NULL, /* done */
92 ZERO_NULL, /* do_more */
93 gopher_connect, /* connect_it */
94 gopher_connecting, /* connecting */
95 ZERO_NULL, /* doing */
96 ZERO_NULL, /* proto_getsock */
97 ZERO_NULL, /* doing_getsock */
98 ZERO_NULL, /* domore_getsock */
99 ZERO_NULL, /* perform_getsock */
100 ZERO_NULL, /* disconnect */
101 ZERO_NULL, /* readwrite */
102 ZERO_NULL, /* connection_check */
103 ZERO_NULL, /* attach connection */
104 PORT_GOPHER, /* defport */
105 CURLPROTO_GOPHERS, /* protocol */
106 CURLPROTO_GOPHER, /* family */
107 PROTOPT_SSL /* flags */
108};
109
110static CURLcode gopher_connect(struct Curl_easy *data, bool *done)
111{
112 (void)data;
113 (void)done;
114 return CURLE_OK;
115}
116
117static CURLcode gopher_connecting(struct Curl_easy *data, bool *done)
118{
119 struct connectdata *conn = data->conn;
120 CURLcode result = Curl_ssl_connect(data, conn, FIRSTSOCKET);
121 if(result)
122 connclose(conn, "Failed TLS connection");
123 *done = TRUE;
124 return result;
125}
126#endif
127
128static CURLcode gopher_do(struct Curl_easy *data, bool *done)
129{
130 CURLcode result = CURLE_OK;
131 struct connectdata *conn = data->conn;
132 curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
133 char *gopherpath;
134 char *path = data->state.up.path;
135 char *query = data->state.up.query;
136 char *sel = NULL;
137 char *sel_org = NULL;
138 timediff_t timeout_ms;
139 ssize_t amount, k;
140 size_t len;
141 int what;
142
143 *done = TRUE; /* unconditionally */
144
145 /* path is guaranteed non-NULL */
146 DEBUGASSERT(path);
147
148 if(query)
149 gopherpath = aprintf("%s?%s", path, query);
150 else
151 gopherpath = strdup(path);
152
153 if(!gopherpath)
154 return CURLE_OUT_OF_MEMORY;
155
156 /* Create selector. Degenerate cases: / and /1 => convert to "" */
157 if(strlen(gopherpath) <= 2) {
158 sel = (char *)"";
159 len = strlen(sel);
160 free(gopherpath);
161 }
162 else {
163 char *newp;
164
165 /* Otherwise, drop / and the first character (i.e., item type) ... */
166 newp = gopherpath;
167 newp += 2;
168
169 /* ... and finally unescape */
170 result = Curl_urldecode(newp, 0, &sel, &len, REJECT_ZERO);
171 free(gopherpath);
172 if(result)
173 return result;
174 sel_org = sel;
175 }
176
177 k = curlx_uztosz(len);
178
179 for(;;) {
180 /* Break out of the loop if the selector is empty because OpenSSL and/or
181 LibreSSL fail with errno 0 if this is the case. */
182 if(strlen(sel) < 1)
183 break;
184
185 result = Curl_write(data, sockfd, sel, k, &amount);
186 if(!result) { /* Which may not have written it all! */
187 result = Curl_client_write(data, CLIENTWRITE_HEADER, sel, amount);
188 if(result)
189 break;
190
191 k -= amount;
192 sel += amount;
193 if(k < 1)
194 break; /* but it did write it all */
195 }
196 else
197 break;
198
199 timeout_ms = Curl_timeleft(data, NULL, FALSE);
200 if(timeout_ms < 0) {
201 result = CURLE_OPERATION_TIMEDOUT;
202 break;
203 }
204 if(!timeout_ms)
205 timeout_ms = TIMEDIFF_T_MAX;
206
207 /* Don't busyloop. The entire loop thing is a work-around as it causes a
208 BLOCKING behavior which is a NO-NO. This function should rather be
209 split up in a do and a doing piece where the pieces that aren't
210 possible to send now will be sent in the doing function repeatedly
211 until the entire request is sent.
212 */
213 what = SOCKET_WRITABLE(sockfd, timeout_ms);
214 if(what < 0) {
215 result = CURLE_SEND_ERROR;
216 break;
217 }
218 else if(!what) {
219 result = CURLE_OPERATION_TIMEDOUT;
220 break;
221 }
222 }
223
224 free(sel_org);
225
226 if(!result)
227 result = Curl_write(data, sockfd, "\r\n", 2, &amount);
228 if(result) {
229 failf(data, "Failed sending Gopher request");
230 return result;
231 }
232 result = Curl_client_write(data, CLIENTWRITE_HEADER, (char *)"\r\n", 2);
233 if(result)
234 return result;
235
236 Curl_setup_transfer(data, FIRSTSOCKET, -1, FALSE, -1);
237 return CURLE_OK;
238}
239#endif /*CURL_DISABLE_GOPHER*/
240