keyserver/gpgkeys_curl.c

   1 /* gpgkeys_curl.c - fetch a key via libcurl
   2  * Copyright (C) 2004, 2005, 2006 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 2 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, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  19  * USA.
  20  *
  21  * In addition, as a special exception, the Free Software Foundation
  22  * gives permission to link the code of the keyserver helper tools:
  23  * gpgkeys_ldap, gpgkeys_curl and gpgkeys_hkp with the OpenSSL
  24  * project's "OpenSSL" library (or with modified versions of it that
  25  * use the same license as the "OpenSSL" library), and distribute the
  26  * linked executables.  You must obey the GNU General Public License
  27  * in all respects for all of the code used other than "OpenSSL".  If
  28  * you modify this file, you may extend this exception to your version
  29  * of the file, but you are not obligated to do so.  If you do not
  30  * wish to do so, delete this exception statement from your version.
  31  */
  32
  33 #include <config.h>
  34 #include <stdio.h>
  35 #include <string.h>
  36 #include <stdlib.h>
  37 #include <errno.h>
  38 #include <unistd.h>
  39 #ifdef HAVE_GETOPT_H
  40 #include <getopt.h>
  41 #endif
  42 #ifdef HAVE_LIBCURL
  43 #include <curl/curl.h>
  44 #else
  45 #include "curl-shim.h"
  46 #endif
  47 #include "keyserver.h"
  48 #include "ksutil.h"
  49
  50 extern char *optarg;
  51 extern int optind;
  52
  53 static FILE *input,*output,*console;
  54 static CURL *curl;
  55 static struct ks_options *opt;
  56
  57 static int
  58 get_key(char *getkey)
  59 {
  60   CURLcode res;
  61   char errorbuffer[CURL_ERROR_SIZE];
  62   char request[MAX_URL];
  63   struct curl_writer_ctx ctx;
  64
  65   memset(&ctx,0,sizeof(ctx));
  66
  67   if(strncmp(getkey,"0x",2)==0)
  68     getkey+=2;
  69
  70   fprintf(output,"KEY 0x%s BEGIN\n",getkey);
  71
  72   sprintf(request,"%s://%s%s%s%s",opt->scheme,opt->host,
  73           opt->port?":":"",opt->port?opt->port:"",opt->path?opt->path:"/");
  74
  75   curl_easy_setopt(curl,CURLOPT_URL,request);
  76   curl_easy_setopt(curl,CURLOPT_WRITEFUNCTION,curl_writer);
  77   ctx.stream=output;
  78   curl_easy_setopt(curl,CURLOPT_FILE,&ctx);
  79   curl_easy_setopt(curl,CURLOPT_ERRORBUFFER,errorbuffer);
  80
  81   res=curl_easy_perform(curl);
  82   if(res!=CURLE_OK)
  83     {
  84       fprintf(console,"gpgkeys: %s fetch error %d: %s\n",opt->scheme,
  85               res,errorbuffer);
  86       fprintf(output,"\nKEY 0x%s FAILED %d\n",getkey,curl_err_to_gpg_err(res));
  87     }
  88   else
  89     {
  90       curl_writer_finalize(&ctx);
  91       if(!ctx.flags.done)
  92         {
  93           fprintf(console,"gpgkeys: no key data found for %s\n",request);
  94           fprintf(output,"\nKEY 0x%s FAILED %d\n",
  95                   getkey,KEYSERVER_KEY_NOT_FOUND);
  96         }
  97       else
  98         fprintf(output,"\nKEY 0x%s END\n",getkey);
  99     }
 100
 101   return curl_err_to_gpg_err(res);
 102 }
 103
 104 static void
 105 show_help (FILE *fp)
 106 {
 107   fprintf (fp,"-h\thelp\n");
 108   fprintf (fp,"-V\tversion\n");
 109   fprintf (fp,"-o\toutput to this file\n");
 110 }
 111
 112 int
 113 main(int argc,char *argv[])
 114 {
 115   int arg,ret=KEYSERVER_INTERNAL_ERROR;
 116   char line[MAX_LINE];
 117   char *thekey=NULL;
 118   long follow_redirects=5;
 119   char *proxy=NULL;
 120
 121   console=stderr;
 122
 123   /* Kludge to implement standard GNU options.  */
 124   if (argc > 1 && !strcmp (argv[1], "--version"))
 125     {
 126       fputs ("gpgkeys_curl (GnuPG) " VERSION"\n", stdout);
 127       return 0;
 128     }
 129   else if (argc > 1 && !strcmp (argv[1], "--help"))
 130     {
 131       show_help (stdout);
 132       return 0;
 133     }
 134
 135   while((arg=getopt(argc,argv,"hVo:"))!=-1)
 136     switch(arg)
 137       {
 138       default:
 139       case 'h':
 140         show_help (console);
 141         return KEYSERVER_OK;
 142
 143       case 'V':
 144         fprintf(stdout,"%d\n%s\n",KEYSERVER_PROTO_VERSION,VERSION);
 145         return KEYSERVER_OK;
 146
 147       case 'o':
 148         output=fopen(optarg,"wb");
 149         if(output==NULL)
 150           {
 151             fprintf(console,"gpgkeys: Cannot open output file `%s': %s\n",
 152                     optarg,strerror(errno));
 153             return KEYSERVER_INTERNAL_ERROR;
 154           }
 155
 156         break;
 157       }
 158
 159   if(argc>optind)
 160     {
 161       input=fopen(argv[optind],"r");
 162       if(input==NULL)
 163         {
 164           fprintf(console,"gpgkeys: Cannot open input file `%s': %s\n",
 165                   argv[optind],strerror(errno));
 166           return KEYSERVER_INTERNAL_ERROR;
 167         }
 168     }
 169
 170   if(input==NULL)
 171     input=stdin;
 172
 173   if(output==NULL)
 174     output=stdout;
 175
 176   opt=init_ks_options();
 177   if(!opt)
 178     return KEYSERVER_NO_MEMORY;
 179
 180   /* Get the command and info block */
 181
 182   while(fgets(line,MAX_LINE,input)!=NULL)
 183     {
 184       int err;
 185       char option[MAX_OPTION+1];
 186
 187       if(line[0]=='\n')
 188         break;
 189
 190       err=parse_ks_options(line,opt);
 191       if(err>0)
 192         {
 193           ret=err;
 194           goto fail;
 195         }
 196       else if(err==0)
 197         continue;
 198
 199       if(sscanf(line,"OPTION %" MKSTRING(MAX_OPTION) "s\n",option)==1)
 200         {
 201           int no=0;
 202           char *start=&option[0];
 203
 204           option[MAX_OPTION]='\0';
 205
 206           if(strncasecmp(option,"no-",3)==0)
 207             {
 208               no=1;
 209               start=&option[3];
 210             }
 211
 212           if(strncasecmp(start,"http-proxy",10)==0)
 213             {
 214               /* Safe to not check the return code of strdup() here.
 215                  If it fails, we simply won't use a proxy. */
 216               if(no)
 217                 {
 218                   free(proxy);
 219                   proxy=strdup("");
 220                 }
 221               else if(start[10]=='=')
 222                 {
 223                   if(strlen(&start[11])<MAX_PROXY)
 224                     {
 225                       free(proxy);
 226                       proxy=strdup(&start[11]);
 227                     }
 228                 }
 229             }
 230           else if(strncasecmp(start,"follow-redirects",16)==0)
 231             {
 232               if(no)
 233                 follow_redirects=0;
 234               else if(start[16]=='=')
 235                 follow_redirects=atoi(&start[17]);
 236               else if(start[16]=='\0')
 237                 follow_redirects=-1;
 238             }
 239
 240           continue;
 241         }
 242     }
 243
 244   if(!opt->scheme)
 245     {
 246       fprintf(console,"gpgkeys: no scheme supplied!\n");
 247       ret=KEYSERVER_SCHEME_NOT_FOUND;
 248       goto fail;
 249     }
 250
 251   if(!opt->host)
 252     {
 253       fprintf(console,"gpgkeys: no keyserver host provided\n");
 254       goto fail;
 255     }
 256
 257   if(opt->timeout && register_timeout()==-1)
 258     {
 259       fprintf(console,"gpgkeys: unable to register timeout handler\n");
 260       return KEYSERVER_INTERNAL_ERROR;
 261     }
 262
 263   curl_global_init(CURL_GLOBAL_DEFAULT);
 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   if(follow_redirects)
 273     {
 274       curl_easy_setopt(curl,CURLOPT_FOLLOWLOCATION,1);
 275       if(follow_redirects>0)
 276         curl_easy_setopt(curl,CURLOPT_MAXREDIRS,follow_redirects);
 277     }
 278
 279   if(opt->auth)
 280     curl_easy_setopt(curl,CURLOPT_USERPWD,opt->auth);
 281
 282   if(opt->debug)
 283     {
 284       fprintf(console,"gpgkeys: curl version = %s\n",curl_version());
 285       curl_easy_setopt(curl,CURLOPT_STDERR,console);
 286       curl_easy_setopt(curl,CURLOPT_VERBOSE,1);
 287     }
 288
 289   curl_easy_setopt(curl,CURLOPT_SSL_VERIFYPEER,opt->flags.check_cert);
 290   curl_easy_setopt(curl,CURLOPT_CAINFO,opt->ca_cert_file);
 291
 292   if(proxy)
 293     curl_easy_setopt(curl,CURLOPT_PROXY,proxy);
 294
 295   /* If it's a GET or a SEARCH, the next thing to come in is the
 296      keyids.  If it's a SEND, then there are no keyids. */
 297
 298   if(opt->action==KS_GET)
 299     {
 300       /* Eat the rest of the file */
 301       for(;;)
 302         {
 303           if(fgets(line,MAX_LINE,input)==NULL)
 304             break;
 305           else
 306             {
 307               if(line[0]=='\n' || line[0]=='\0')
 308                 break;
 309
 310               if(!thekey)
 311                 {
 312                   thekey=strdup(line);
 313                   if(!thekey)
 314                     {
 315                       fprintf(console,"gpgkeys: out of memory while "
 316                               "building key list\n");
 317                       ret=KEYSERVER_NO_MEMORY;
 318                       goto fail;
 319                     }
 320
 321                   /* Trim the trailing \n */
 322                   thekey[strlen(line)-1]='\0';
 323                 }
 324             }
 325         }
 326     }
 327   else
 328     {
 329       fprintf(console,
 330               "gpgkeys: this keyserver type only supports key retrieval\n");
 331       goto fail;
 332     }
 333
 334   if(!thekey)
 335     {
 336       fprintf(console,"gpgkeys: invalid keyserver instructions\n");
 337       goto fail;
 338     }
 339
 340   /* Send the response */
 341
 342   fprintf(output,"VERSION %d\n",KEYSERVER_PROTO_VERSION);
 343   fprintf(output,"PROGRAM %s\n\n",VERSION);
 344
 345   if(opt->verbose)
 346     {
 347       fprintf(console,"Scheme:\t\t%s\n",opt->scheme);
 348       fprintf(console,"Host:\t\t%s\n",opt->host);
 349       if(opt->port)
 350         fprintf(console,"Port:\t\t%s\n",opt->port);
 351       if(opt->path)
 352         fprintf(console,"Path:\t\t%s\n",opt->path);
 353       fprintf(console,"Command:\tGET\n");
 354     }
 355
 356   set_timeout(opt->timeout);
 357
 358   ret=get_key(thekey);
 359
 360  fail:
 361
 362   free(thekey);
 363
 364   if(input!=stdin)
 365     fclose(input);
 366
 367   if(output!=stdout)
 368     fclose(output);
 369
 370   free_ks_options(opt);
 371
 372   if(curl)
 373     curl_easy_cleanup(curl);
 374
 375   free(proxy);
 376
 377   curl_global_cleanup();
 378
 379   return ret;
 380 }