keyserver/gpgkeys_curl.c

   1 /* gpgkeys_curl.c - fetch a key via libcurl
   2  * Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
   3  *
   4  * This file is part of GnuPG.
   5  *
   6  * GnuPG is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * GnuPG is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  * In addition, as a special exception, the Free Software Foundation
  20  * gives permission to link the code of the keyserver helper tools:
  21  * gpgkeys_ldap, gpgkeys_curl and gpgkeys_hkp with the OpenSSL
  22  * project's "OpenSSL" library (or with modified versions of it that
  23  * use the same license as the "OpenSSL" library), and distribute the
  24  * linked executables.  You must obey the GNU General Public License
  25  * in all respects for all of the code used other than "OpenSSL".  If
  26  * you modify this file, you may extend this exception to your version
  27  * of the file, but you are not obligated to do so.  If you do not
  28  * wish to do so, delete this exception statement from your version.
  29  */
  30
  31 #include <config.h>
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <stdlib.h>
  35 #include <errno.h>
  36 #include <unistd.h>
  37 #ifdef HAVE_GETOPT_H
  38 #include <getopt.h>
  39 #endif
  40 #ifdef HAVE_LIBCURL
  41 #include <curl/curl.h>
  42 #else
  43 #include "curl-shim.h"
  44 #endif
  45 #include "keyserver.h"
  46 #include "ksutil.h"
  47
  48 extern char *optarg;
  49 extern int optind;
  50
  51 static FILE *input,*output,*console;
  52 static CURL *curl;
  53 static struct ks_options *opt;
  54
  55 static int
  56 get_key(char *getkey)
  57 {
  58   CURLcode res;
  59   char errorbuffer[CURL_ERROR_SIZE];
  60   char request[MAX_URL];
  61   struct curl_writer_ctx ctx;
  62
  63   memset(&ctx,0,sizeof(ctx));
  64
  65   if(strncmp(getkey,"0x",2)==0)
  66     getkey+=2;
  67
  68   fprintf(output,"KEY 0x%s BEGIN\n",getkey);
  69
  70   sprintf(request,"%s://%s%s%s%s",opt->scheme,opt->host,
  71           opt->port?":":"",opt->port?opt->port:"",opt->path?opt->path:"/");
  72
  73   curl_easy_setopt(curl,CURLOPT_URL,request);
  74   curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,curl_writer);
  75   ctx.stream=output;
  76   curl_easy_setopt(curl,CURLOPT_FILE,&ctx);
  77   curl_easy_setopt(curl,CURLOPT_ERRORBUFFER,errorbuffer);
  78
  79   res=curl_easy_perform(curl);
  80   if(res!=CURLE_OK)
  81     {
  82       fprintf(console,"gpgkeys: %s fetch error %d: %s\n",opt->scheme,
  83               res,errorbuffer);
  84       fprintf(output,"\nKEY 0x%s FAILED %d\n",getkey,curl_err_to_gpg_err(res));
  85     }
  86   else
  87     {
  88       curl_writer_finalize(&ctx);
  89       if(!ctx.flags.done)
  90         {
  91           fprintf(console,"gpgkeys: no key data found for %s\n",request);
  92           fprintf(output,"\nKEY 0x%s FAILED %d\n",
  93                   getkey,KEYSERVER_KEY_NOT_FOUND);
  94         }
  95       else
  96         fprintf(output,"\nKEY 0x%s END\n",getkey);
  97     }
  98
  99   return curl_err_to_gpg_err(res);
 100 }
 101
 102 static void
 103 show_help (FILE *fp)
 104 {
 105   fprintf (fp,"-h\thelp\n");
 106   fprintf (fp,"-V\tversion\n");
 107   fprintf (fp,"-o\toutput to this file\n");
 108 }
 109
 110 int
 111 main(int argc,char *argv[])
 112 {
 113   int arg,ret=KEYSERVER_INTERNAL_ERROR,i;
 114   char line[MAX_LINE];
 115   char *thekey=NULL;
 116   long follow_redirects=5;
 117   char *proxy=NULL;
 118   curl_version_info_data *curldata;
 119
 120   console=stderr;
 121
 122   /* Kludge to implement standard GNU options.  */
 123   if (argc > 1 && !strcmp (argv[1], "--version"))
 124     {
 125       fputs ("gpgkeys_curl (GnuPG) " VERSION"\n", stdout);
 126       return 0;
 127     }
 128   else if (argc > 1 && !strcmp (argv[1], "--help"))
 129     {
 130       show_help (stdout);
 131       return 0;
 132     }
 133
 134   while((arg=getopt(argc,argv,"hVo:"))!=-1)
 135     switch(arg)
 136       {
 137       default:
 138       case 'h':
 139         show_help (console);
 140         return KEYSERVER_OK;
 141
 142       case 'V':
 143         fprintf(stdout,"%d\n%s\n",KEYSERVER_PROTO_VERSION,VERSION);
 144         return KEYSERVER_OK;
 145
 146       case 'o':
 147         output=fopen(optarg,"wb");
 148         if(output==NULL)
 149           {
 150             fprintf(console,"gpgkeys: Cannot open output file `%s': %s\n",
 151                     optarg,strerror(errno));
 152             return KEYSERVER_INTERNAL_ERROR;
 153           }
 154
 155         break;
 156       }
 157
 158   if(argc>optind)
 159     {
 160       input=fopen(argv[optind],"r");
 161       if(input==NULL)
 162         {
 163           fprintf(console,"gpgkeys: Cannot open input file `%s': %s\n",
 164                   argv[optind],strerror(errno));
 165           return KEYSERVER_INTERNAL_ERROR;
 166         }
 167     }
 168
 169   if(input==NULL)
 170     input=stdin;
 171
 172   if(output==NULL)
 173     output=stdout;
 174
 175   opt=init_ks_options();
 176   if(!opt)
 177     return KEYSERVER_NO_MEMORY;
 178
 179   /* Get the command and info block */
 180
 181   while(fgets(line,MAX_LINE,input)!=NULL)
 182     {
 183       int err;
 184       char option[MAX_OPTION+1];
 185
 186       if(line[0]=='\n')
 187         break;
 188
 189       err=parse_ks_options(line,opt);
 190       if(err>0)
 191         {
 192           ret=err;
 193           goto fail;
 194         }
 195       else if(err==0)
 196         continue;
 197
 198       if(sscanf(line,"OPTION %" MKSTRING(MAX_OPTION) "s\n",option)==1)
 199         {
 200           int no=0;
 201           char *start=&option[0];
 202
 203           option[MAX_OPTION]='\0';
 204
 205           if(strncasecmp(option,"no-",3)==0)
 206             {
 207               no=1;
 208               start=&option[3];
 209             }
 210
 211           if(strncasecmp(start,"http-proxy",10)==0)
 212             {
 213               /* Safe to not check the return code of strdup() here.
 214                  If it fails, we simply won't use a proxy. */
 215               if(no)
 216                 {
 217                   free(proxy);
 218                   proxy=strdup("");
 219                 }
 220               else if(start[10]=='=')
 221                 {
 222                   if(strlen(&start[11])<MAX_PROXY)
 223                     {
 224                       free(proxy);
 225                       proxy=strdup(&start[11]);
 226                     }
 227                 }
 228             }
 229           else if(strncasecmp(start,"follow-redirects",16)==0)
 230             {
 231               if(no)
 232                 follow_redirects=0;
 233               else if(start[16]=='=')
 234                 follow_redirects=atoi(&start[17]);
 235               else if(start[16]=='\0')
 236                 follow_redirects=-1;
 237             }
 238
 239           continue;
 240         }
 241     }
 242
 243   if(!opt->scheme)
 244     {
 245       fprintf(console,"gpgkeys: no scheme supplied!\n");
 246       ret=KEYSERVER_SCHEME_NOT_FOUND;
 247       goto fail;
 248     }
 249
 250   if(!opt->host)
 251     {
 252       fprintf(console,"gpgkeys: no keyserver host provided\n");
 253       goto fail;
 254     }
 255
 256   if(opt->timeout && register_timeout()==-1)
 257     {
 258       fprintf(console,"gpgkeys: unable to register timeout handler\n");
 259       return KEYSERVER_INTERNAL_ERROR;
 260     }
 261
 262   curl_global_init(CURL_GLOBAL_DEFAULT);
 263
 264   curl=curl_easy_init();
 265   if(!curl)
 266     {
 267       fprintf(console,"gpgkeys: unable to initialize curl\n");
 268       ret=KEYSERVER_INTERNAL_ERROR;
 269       goto fail;
 270     }
 271
 272   /* Make sure we have the protocol the user is asking for so we can
 273      print a nicer error message. */
 274   curldata=curl_version_info(CURLVERSION_NOW);
 275   for(i=0;curldata->protocols[i];i++)
 276     if(strcasecmp(curldata->protocols[i],opt->scheme)==0)
 277       break;
 278
 279   if(curldata->protocols[i]==NULL)
 280     {
 281       fprintf(console,"gpgkeys: protocol `%s' not supported\n",opt->scheme);
 282       ret=KEYSERVER_SCHEME_NOT_FOUND;
 283       goto fail;
 284     }
 285
 286   if(follow_redirects)
 287     {
 288       curl_easy_setopt(curl,CURLOPT_FOLLOWLOCATION,1);
 289       if(follow_redirects>0)
 290         curl_easy_setopt(curl,CURLOPT_MAXREDIRS,follow_redirects);
 291     }
 292
 293   if(opt->auth)
 294     curl_easy_setopt(curl,CURLOPT_USERPWD,opt->auth);
 295
 296   if(opt->debug)
 297     {
 298       fprintf(console,"gpgkeys: curl version = %s\n",curl_version());
 299       curl_easy_setopt(curl,CURLOPT_STDERR,console);
 300       curl_easy_setopt(curl,CURLOPT_VERBOSE,1);
 301     }
 302
 303   curl_easy_setopt(curl,CURLOPT_SSL_VERIFYPEER,opt->flags.check_cert);
 304   curl_easy_setopt(curl,CURLOPT_CAINFO,opt->ca_cert_file);
 305
 306   if(proxy)
 307     curl_easy_setopt(curl,CURLOPT_PROXY,proxy);
 308
 309   /* If it's a GET or a SEARCH, the next thing to come in is the
 310      keyids.  If it's a SEND, then there are no keyids. */
 311
 312   if(opt->action==KS_GET)
 313     {
 314       /* Eat the rest of the file */
 315       for(;;)
 316         {
 317           if(fgets(line,MAX_LINE,input)==NULL)
 318             break;
 319           else
 320             {
 321               if(line[0]=='\n' || line[0]=='\0')
 322                 break;
 323
 324               if(!thekey)
 325                 {
 326                   thekey=strdup(line);
 327                   if(!thekey)
 328                     {
 329                       fprintf(console,"gpgkeys: out of memory while "
 330                               "building key list\n");
 331                       ret=KEYSERVER_NO_MEMORY;
 332                       goto fail;
 333                     }
 334
 335                   /* Trim the trailing \n */
 336                   thekey[strlen(line)-1]='\0';
 337                 }
 338             }
 339         }
 340     }
 341   else
 342     {
 343       fprintf(console,
 344               "gpgkeys: this keyserver type only supports key retrieval\n");
 345       goto fail;
 346     }
 347
 348   if(!thekey)
 349     {
 350       fprintf(console,"gpgkeys: invalid keyserver instructions\n");
 351       goto fail;
 352     }
 353
 354   /* Send the response */
 355
 356   fprintf(output,"VERSION %d\n",KEYSERVER_PROTO_VERSION);
 357   fprintf(output,"PROGRAM %s\n\n",VERSION);
 358
 359   if(opt->verbose)
 360     {
 361       fprintf(console,"Scheme:\t\t%s\n",opt->scheme);
 362       fprintf(console,"Host:\t\t%s\n",opt->host);
 363       if(opt->port)
 364         fprintf(console,"Port:\t\t%s\n",opt->port);
 365       if(opt->path)
 366         fprintf(console,"Path:\t\t%s\n",opt->path);
 367       fprintf(console,"Command:\tGET\n");
 368     }
 369
 370   set_timeout(opt->timeout);
 371
 372   ret=get_key(thekey);
 373
 374  fail:
 375
 376   free(thekey);
 377
 378   if(input!=stdin)
 379     fclose(input);
 380
 381   if(output!=stdout)
 382     fclose(output);
 383
 384   free_ks_options(opt);
 385
 386   if(curl)
 387     curl_easy_cleanup(curl);
 388
 389   free(proxy);
 390
 391   curl_global_cleanup();
 392
 393   return ret;
 394 }