1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2021, 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 ***************************************************************************/
22
23#include "curl_setup.h"
24
25#ifndef CURL_DISABLE_GOPHER
26
27#include "urldata.h"
28#include <curl/curl.h>
29#include "transfer.h"
30#include "sendf.h"
31#include "connect.h"
32#include "progress.h"
33#include "gopher.h"
34#include "select.h"
35#include "strdup.h"
36#include "vtls/vtls.h"
37#include "url.h"
38#include "escape.h"
39#include "warnless.h"
40#include "curl_printf.h"
41#include "curl_memory.h"
42/* The last #include file should be: */
43#include "memdebug.h"
44
45/*
46 * Forward declarations.
47 */
48
49static CURLcode gopher_do(struct Curl_easy *data, bool *done);
50#ifdef USE_SSL
51static CURLcode gopher_connect(struct Curl_easy *data, bool *done);
52static CURLcode gopher_connecting(struct Curl_easy *data, bool *done);
53#endif
54
55/*
56 * Gopher protocol handler.
57 * This is also a nice simple template to build off for simple
58 * connect-command-download protocols.
59 */
60
61const struct Curl_handler Curl_handler_gopher = {
62 "GOPHER", /* scheme */
63 ZERO_NULL, /* setup_connection */
64 gopher_do, /* do_it */
65 ZERO_NULL, /* done */
66 ZERO_NULL, /* do_more */
67 ZERO_NULL, /* connect_it */
68 ZERO_NULL, /* connecting */
69 ZERO_NULL, /* doing */
70 ZERO_NULL, /* proto_getsock */
71 ZERO_NULL, /* doing_getsock */
72 ZERO_NULL, /* domore_getsock */
73 ZERO_NULL, /* perform_getsock */
74 ZERO_NULL, /* disconnect */
75 ZERO_NULL, /* readwrite */
76 ZERO_NULL, /* connection_check */
77 ZERO_NULL, /* attach connection */
78 PORT_GOPHER, /* defport */
79 CURLPROTO_GOPHER, /* protocol */
80 CURLPROTO_GOPHER, /* family */
81 PROTOPT_NONE /* flags */
82};
83
84#ifdef USE_SSL
85const struct Curl_handler Curl_handler_gophers = {
86 "GOPHERS", /* scheme */
87 ZERO_NULL, /* setup_connection */
88 gopher_do, /* do_it */
89 ZERO_NULL, /* done */
90 ZERO_NULL, /* do_more */
91 gopher_connect, /* connect_it */
92 gopher_connecting, /* connecting */
93 ZERO_NULL, /* doing */
94 ZERO_NULL, /* proto_getsock */
95 ZERO_NULL, /* doing_getsock */
96 ZERO_NULL, /* domore_getsock */
97 ZERO_NULL, /* perform_getsock */
98 ZERO_NULL, /* disconnect */
99 ZERO_NULL, /* readwrite */
100 ZERO_NULL, /* connection_check */
101 ZERO_NULL, /* attach connection */
102 PORT_GOPHER, /* defport */
103 CURLPROTO_GOPHERS, /* protocol */
104 CURLPROTO_GOPHER, /* family */
105 PROTOPT_SSL /* flags */
106};
107
108static CURLcode gopher_connect(struct Curl_easy *data, bool *done)
109{
110 (void)data;
111 (void)done;
112 return CURLE_OK;
113}
114
115static CURLcode gopher_connecting(struct Curl_easy *data, bool *done)
116{
117 struct connectdata *conn = data->conn;
118 CURLcode result = Curl_ssl_connect(data, conn, FIRSTSOCKET);
119 if(result)
120 connclose(conn, "Failed TLS connection");
121 *done = TRUE;
122 return result;
123}
124#endif
125
126static CURLcode gopher_do(struct Curl_easy *data, bool *done)
127{
128 CURLcode result = CURLE_OK;
129 struct connectdata *conn = data->conn;
130 curl_socket_t sockfd = conn->sock[FIRSTSOCKET];
131 char *gopherpath;
132 char *path = data->state.up.path;
133 char *query = data->state.up.query;
134 char *sel = NULL;
135 char *sel_org = NULL;
136 timediff_t timeout_ms;
137 ssize_t amount, k;
138 size_t len;
139 int what;
140
141 *done = TRUE; /* unconditionally */
142
143 /* path is guaranteed non-NULL */
144 DEBUGASSERT(path);
145
146 if(query)
147 gopherpath = aprintf("%s?%s", path, query);
148 else
149 gopherpath = strdup(path);
150
151 if(!gopherpath)
152 return CURLE_OUT_OF_MEMORY;
153
154 /* Create selector. Degenerate cases: / and /1 => convert to "" */
155 if(strlen(gopherpath) <= 2) {
156 sel = (char *)"";
157 len = strlen(sel);
158 free(gopherpath);
159 }
160 else {
161 char *newp;
162
163 /* Otherwise, drop / and the first character (i.e., item type) ... */
164 newp = gopherpath;
165 newp += 2;
166
167 /* ... and finally unescape */
168 result = Curl_urldecode(data, newp, 0, &sel, &len, REJECT_ZERO);
169 free(gopherpath);
170 if(result)
171 return result;
172 sel_org = sel;
173 }
174
175 k = curlx_uztosz(len);
176
177 for(;;) {
178 /* Break out of the loop if the selector is empty because OpenSSL and/or
179 LibreSSL fail with errno 0 if this is the case. */
180 if(strlen(sel) < 1)
181 break;
182
183 result = Curl_write(data, sockfd, sel, k, &amount);
184 if(!result) { /* Which may not have written it all! */
185 result = Curl_client_write(data, CLIENTWRITE_HEADER, sel, amount);
186 if(result)
187 break;
188
189 k -= amount;
190 sel += amount;
191 if(k < 1)
192 break; /* but it did write it all */
193 }
194 else
195 break;
196
197 timeout_ms = Curl_timeleft(data, NULL, FALSE);
198 if(timeout_ms < 0) {
199 result = CURLE_OPERATION_TIMEDOUT;
200 break;
201 }
202 if(!timeout_ms)
203 timeout_ms = TIMEDIFF_T_MAX;
204
205 /* Don't busyloop. The entire loop thing is a work-around as it causes a
206 BLOCKING behavior which is a NO-NO. This function should rather be
207 split up in a do and a doing piece where the pieces that aren't
208 possible to send now will be sent in the doing function repeatedly
209 until the entire request is sent.
210 */
211 what = SOCKET_WRITABLE(sockfd, timeout_ms);
212 if(what < 0) {
213 result = CURLE_SEND_ERROR;
214 break;
215 }
216 else if(!what) {
217 result = CURLE_OPERATION_TIMEDOUT;
218 break;
219 }
220 }
221
222 free(sel_org);
223
224 if(!result)
225 result = Curl_write(data, sockfd, "\r\n", 2, &amount);
226 if(result) {
227 failf(data, "Failed sending Gopher request");
228 return result;
229 }
230 result = Curl_client_write(data, CLIENTWRITE_HEADER, (char *)"\r\n", 2);
231 if(result)
232 return result;
233
234 Curl_setup_transfer(data, FIRSTSOCKET, -1, FALSE, -1);
235 return CURLE_OK;
236}
237#endif /*CURL_DISABLE_GOPHER*/
238