Utilities/cmcurl/lib/gopher.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
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   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2022, 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
  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
  51 static CURLcode gopher_do(struct Curl_easy *data, bool *done);
  52 #ifdef USE_SSL
  53 static CURLcode gopher_connect(struct Curl_easy *data, bool *done);
  54 static 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
  63 const 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
  87 const 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
 110 static CURLcode gopher_connect(struct Curl_easy *data, bool *done)
 111 {
 112   (void)data;
 113   (void)done;
 114   return CURLE_OK;
 115 }
 116
 117 static 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
 128 static 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*/