RFC4507 (including RFC4507bis) TLS stateless session resumption support
[openssl.git] / apps / enc.c
1 /* apps/enc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  * 
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  * 
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  * 
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from 
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  * 
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  * 
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include "apps.h"
63 #include <openssl/bio.h>
64 #include <openssl/err.h>
65 #include <openssl/evp.h>
66 #include <openssl/objects.h>
67 #include <openssl/x509.h>
68 #include <openssl/rand.h>
69 #include <openssl/pem.h>
70 #include <ctype.h>
71
72 int set_hex(char *in,unsigned char *out,int size);
73 #undef SIZE
74 #undef BSIZE
75 #undef PROG
76
77 #define SIZE    (512)
78 #define BSIZE   (8*1024)
79 #define PROG    enc_main
80
81 static void show_ciphers(const OBJ_NAME *name,void *bio_)
82         {
83         BIO *bio=bio_;
84         static int n;
85
86         if(!islower((unsigned char)*name->name))
87                 return;
88
89         BIO_printf(bio,"-%-25s",name->name);
90         if(++n == 3)
91                 {
92                 BIO_printf(bio,"\n");
93                 n=0;
94                 }
95         else
96                 BIO_printf(bio," ");
97         }
98
99 int MAIN(int, char **);
100
101 int MAIN(int argc, char **argv)
102         {
103 #ifndef OPENSSL_NO_ENGINE
104         ENGINE *e = NULL;
105 #endif
106         static const char magic[]="Salted__";
107         char mbuf[sizeof magic-1];
108         char *strbuf=NULL;
109         unsigned char *buff=NULL,*bufsize=NULL;
110         int bsize=BSIZE,verbose=0;
111         int ret=1,inl;
112         int nopad = 0;
113         unsigned char key[EVP_MAX_KEY_LENGTH],iv[EVP_MAX_IV_LENGTH];
114         unsigned char salt[PKCS5_SALT_LEN];
115         char *str=NULL, *passarg = NULL, *pass = NULL;
116         char *hkey=NULL,*hiv=NULL,*hsalt = NULL;
117         char *md=NULL;
118         int enc=1,printkey=0,i,base64=0;
119         int debug=0,olb64=0,nosalt=0;
120         const EVP_CIPHER *cipher=NULL,*c;
121         EVP_CIPHER_CTX *ctx = NULL;
122         char *inf=NULL,*outf=NULL;
123         BIO *in=NULL,*out=NULL,*b64=NULL,*benc=NULL,*rbio=NULL,*wbio=NULL;
124 #define PROG_NAME_SIZE  39
125         char pname[PROG_NAME_SIZE+1];
126 #ifndef OPENSSL_NO_ENGINE
127         char *engine = NULL;
128 #endif
129         const EVP_MD *dgst=NULL;
130
131         apps_startup();
132
133         if (bio_err == NULL)
134                 if ((bio_err=BIO_new(BIO_s_file())) != NULL)
135                         BIO_set_fp(bio_err,stderr,BIO_NOCLOSE|BIO_FP_TEXT);
136
137         if (!load_config(bio_err, NULL))
138                 goto end;
139
140         /* first check the program name */
141         program_name(argv[0],pname,sizeof pname);
142         if (strcmp(pname,"base64") == 0)
143                 base64=1;
144
145         cipher=EVP_get_cipherbyname(pname);
146         if (!base64 && (cipher == NULL) && (strcmp(pname,"enc") != 0))
147                 {
148                 BIO_printf(bio_err,"%s is an unknown cipher\n",pname);
149                 goto bad;
150                 }
151
152         argc--;
153         argv++;
154         while (argc >= 1)
155                 {
156                 if      (strcmp(*argv,"-e") == 0)
157                         enc=1;
158                 else if (strcmp(*argv,"-in") == 0)
159                         {
160                         if (--argc < 1) goto bad;
161                         inf= *(++argv);
162                         }
163                 else if (strcmp(*argv,"-out") == 0)
164                         {
165                         if (--argc < 1) goto bad;
166                         outf= *(++argv);
167                         }
168                 else if (strcmp(*argv,"-pass") == 0)
169                         {
170                         if (--argc < 1) goto bad;
171                         passarg= *(++argv);
172                         }
173 #ifndef OPENSSL_NO_ENGINE
174                 else if (strcmp(*argv,"-engine") == 0)
175                         {
176                         if (--argc < 1) goto bad;
177                         engine= *(++argv);
178                         }
179 #endif
180                 else if (strcmp(*argv,"-d") == 0)
181                         enc=0;
182                 else if (strcmp(*argv,"-p") == 0)
183                         printkey=1;
184                 else if (strcmp(*argv,"-v") == 0)
185                         verbose=1;
186                 else if (strcmp(*argv,"-nopad") == 0)
187                         nopad=1;
188                 else if (strcmp(*argv,"-salt") == 0)
189                         nosalt=0;
190                 else if (strcmp(*argv,"-nosalt") == 0)
191                         nosalt=1;
192                 else if (strcmp(*argv,"-debug") == 0)
193                         debug=1;
194                 else if (strcmp(*argv,"-P") == 0)
195                         printkey=2;
196                 else if (strcmp(*argv,"-A") == 0)
197                         olb64=1;
198                 else if (strcmp(*argv,"-a") == 0)
199                         base64=1;
200                 else if (strcmp(*argv,"-base64") == 0)
201                         base64=1;
202                 else if (strcmp(*argv,"-bufsize") == 0)
203                         {
204                         if (--argc < 1) goto bad;
205                         bufsize=(unsigned char *)*(++argv);
206                         }
207                 else if (strcmp(*argv,"-k") == 0)
208                         {
209                         if (--argc < 1) goto bad;
210                         str= *(++argv);
211                         }
212                 else if (strcmp(*argv,"-kfile") == 0)
213                         {
214                         static char buf[128];
215                         FILE *infile;
216                         char *file;
217
218                         if (--argc < 1) goto bad;
219                         file= *(++argv);
220                         infile=fopen(file,"r");
221                         if (infile == NULL)
222                                 {
223                                 BIO_printf(bio_err,"unable to read key from '%s'\n",
224                                         file);
225                                 goto bad;
226                                 }
227                         buf[0]='\0';
228                         fgets(buf,sizeof buf,infile);
229                         fclose(infile);
230                         i=strlen(buf);
231                         if ((i > 0) &&
232                                 ((buf[i-1] == '\n') || (buf[i-1] == '\r')))
233                                 buf[--i]='\0';
234                         if ((i > 0) &&
235                                 ((buf[i-1] == '\n') || (buf[i-1] == '\r')))
236                                 buf[--i]='\0';
237                         if (i < 1)
238                                 {
239                                 BIO_printf(bio_err,"zero length password\n");
240                                 goto bad;
241                                 }
242                         str=buf;
243                         }
244                 else if (strcmp(*argv,"-K") == 0)
245                         {
246                         if (--argc < 1) goto bad;
247                         hkey= *(++argv);
248                         }
249                 else if (strcmp(*argv,"-S") == 0)
250                         {
251                         if (--argc < 1) goto bad;
252                         hsalt= *(++argv);
253                         }
254                 else if (strcmp(*argv,"-iv") == 0)
255                         {
256                         if (--argc < 1) goto bad;
257                         hiv= *(++argv);
258                         }
259                 else if (strcmp(*argv,"-md") == 0)
260                         {
261                         if (--argc < 1) goto bad;
262                         md= *(++argv);
263                         }
264                 else if ((argv[0][0] == '-') &&
265                         ((c=EVP_get_cipherbyname(&(argv[0][1]))) != NULL))
266                         {
267                         cipher=c;
268                         }
269                 else if (strcmp(*argv,"-none") == 0)
270                         cipher=NULL;
271                 else
272                         {
273                         BIO_printf(bio_err,"unknown option '%s'\n",*argv);
274 bad:
275                         BIO_printf(bio_err,"options are\n");
276                         BIO_printf(bio_err,"%-14s input file\n","-in <file>");
277                         BIO_printf(bio_err,"%-14s output file\n","-out <file>");
278                         BIO_printf(bio_err,"%-14s pass phrase source\n","-pass <arg>");
279                         BIO_printf(bio_err,"%-14s encrypt\n","-e");
280                         BIO_printf(bio_err,"%-14s decrypt\n","-d");
281                         BIO_printf(bio_err,"%-14s base64 encode/decode, depending on encryption flag\n","-a/-base64");
282                         BIO_printf(bio_err,"%-14s passphrase is the next argument\n","-k");
283                         BIO_printf(bio_err,"%-14s passphrase is the first line of the file argument\n","-kfile");
284                         BIO_printf(bio_err,"%-14s the next argument is the md to use to create a key\n","-md");
285                         BIO_printf(bio_err,"%-14s   from a passphrase.  One of md2, md5, sha or sha1\n","");
286                         BIO_printf(bio_err,"%-14s salt in hex is the next argument\n","-S");
287                         BIO_printf(bio_err,"%-14s key/iv in hex is the next argument\n","-K/-iv");
288                         BIO_printf(bio_err,"%-14s print the iv/key (then exit if -P)\n","-[pP]");
289                         BIO_printf(bio_err,"%-14s buffer size\n","-bufsize <n>");
290                         BIO_printf(bio_err,"%-14s disable standard block padding\n","-nopad");
291 #ifndef OPENSSL_NO_ENGINE
292                         BIO_printf(bio_err,"%-14s use engine e, possibly a hardware device.\n","-engine e");
293 #endif
294
295                         BIO_printf(bio_err,"Cipher Types\n");
296                         OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
297                                                show_ciphers,
298                                                bio_err);
299                         BIO_printf(bio_err,"\n");
300
301                         goto end;
302                         }
303                 argc--;
304                 argv++;
305                 }
306
307 #ifndef OPENSSL_NO_ENGINE
308         e = setup_engine(bio_err, engine, 0);
309 #endif
310
311         if (md && (dgst=EVP_get_digestbyname(md)) == NULL)
312                 {
313                 BIO_printf(bio_err,"%s is an unsupported message digest type\n",md);
314                 goto end;
315                 }
316
317         if (dgst == NULL)
318                 {
319                 dgst = EVP_md5();
320                 }
321
322         if (bufsize != NULL)
323                 {
324                 unsigned long n;
325
326                 for (n=0; *bufsize; bufsize++)
327                         {
328                         i= *bufsize;
329                         if ((i <= '9') && (i >= '0'))
330                                 n=n*10+i-'0';
331                         else if (i == 'k')
332                                 {
333                                 n*=1024;
334                                 bufsize++;
335                                 break;
336                                 }
337                         }
338                 if (*bufsize != '\0')
339                         {
340                         BIO_printf(bio_err,"invalid 'bufsize' specified.\n");
341                         goto end;
342                         }
343
344                 /* It must be large enough for a base64 encoded line */
345                 if (base64 && n < 80) n=80;
346
347                 bsize=(int)n;
348                 if (verbose) BIO_printf(bio_err,"bufsize=%d\n",bsize);
349                 }
350
351         strbuf=OPENSSL_malloc(SIZE);
352         buff=(unsigned char *)OPENSSL_malloc(EVP_ENCODE_LENGTH(bsize));
353         if ((buff == NULL) || (strbuf == NULL))
354                 {
355                 BIO_printf(bio_err,"OPENSSL_malloc failure %ld\n",(long)EVP_ENCODE_LENGTH(bsize));
356                 goto end;
357                 }
358
359         in=BIO_new(BIO_s_file());
360         out=BIO_new(BIO_s_file());
361         if ((in == NULL) || (out == NULL))
362                 {
363                 ERR_print_errors(bio_err);
364                 goto end;
365                 }
366         if (debug)
367                 {
368                 BIO_set_callback(in,BIO_debug_callback);
369                 BIO_set_callback(out,BIO_debug_callback);
370                 BIO_set_callback_arg(in,(char *)bio_err);
371                 BIO_set_callback_arg(out,(char *)bio_err);
372                 }
373
374         if (inf == NULL)
375                 {
376                 if (bufsize != NULL)
377                         setvbuf(stdin, (char *)NULL, _IONBF, 0);
378                 BIO_set_fp(in,stdin,BIO_NOCLOSE);
379                 }
380         else
381                 {
382                 if (BIO_read_filename(in,inf) <= 0)
383                         {
384                         perror(inf);
385                         goto end;
386                         }
387                 }
388
389         if(!str && passarg) {
390                 if(!app_passwd(bio_err, passarg, NULL, &pass, NULL)) {
391                         BIO_printf(bio_err, "Error getting password\n");
392                         goto end;
393                 }
394                 str = pass;
395         }
396
397         if ((str == NULL) && (cipher != NULL) && (hkey == NULL))
398                 {
399                 for (;;)
400                         {
401                         char buf[200];
402
403                         BIO_snprintf(buf,sizeof buf,"enter %s %s password:",
404                                      OBJ_nid2ln(EVP_CIPHER_nid(cipher)),
405                                      (enc)?"encryption":"decryption");
406                         strbuf[0]='\0';
407                         i=EVP_read_pw_string((char *)strbuf,SIZE,buf,enc);
408                         if (i == 0)
409                                 {
410                                 if (strbuf[0] == '\0')
411                                         {
412                                         ret=1;
413                                         goto end;
414                                         }
415                                 str=strbuf;
416                                 break;
417                                 }
418                         if (i < 0)
419                                 {
420                                 BIO_printf(bio_err,"bad password read\n");
421                                 goto end;
422                                 }
423                         }
424                 }
425
426
427         if (outf == NULL)
428                 {
429                 BIO_set_fp(out,stdout,BIO_NOCLOSE);
430                 if (bufsize != NULL)
431                         setvbuf(stdout, (char *)NULL, _IONBF, 0);
432 #ifdef OPENSSL_SYS_VMS
433                 {
434                 BIO *tmpbio = BIO_new(BIO_f_linebuffer());
435                 out = BIO_push(tmpbio, out);
436                 }
437 #endif
438                 }
439         else
440                 {
441                 if (BIO_write_filename(out,outf) <= 0)
442                         {
443                         perror(outf);
444                         goto end;
445                         }
446                 }
447
448         rbio=in;
449         wbio=out;
450
451         if (base64)
452                 {
453                 if ((b64=BIO_new(BIO_f_base64())) == NULL)
454                         goto end;
455                 if (debug)
456                         {
457                         BIO_set_callback(b64,BIO_debug_callback);
458                         BIO_set_callback_arg(b64,(char *)bio_err);
459                         }
460                 if (olb64)
461                         BIO_set_flags(b64,BIO_FLAGS_BASE64_NO_NL);
462                 if (enc)
463                         wbio=BIO_push(b64,wbio);
464                 else
465                         rbio=BIO_push(b64,rbio);
466                 }
467
468         if (cipher != NULL)
469                 {
470                 /* Note that str is NULL if a key was passed on the command
471                  * line, so we get no salt in that case. Is this a bug?
472                  */
473                 if (str != NULL)
474                         {
475                         /* Salt handling: if encrypting generate a salt and
476                          * write to output BIO. If decrypting read salt from
477                          * input BIO.
478                          */
479                         unsigned char *sptr;
480                         if(nosalt) sptr = NULL;
481                         else {
482                                 if(enc) {
483                                         if(hsalt) {
484                                                 if(!set_hex(hsalt,salt,sizeof salt)) {
485                                                         BIO_printf(bio_err,
486                                                                 "invalid hex salt value\n");
487                                                         goto end;
488                                                 }
489                                         } else if (RAND_pseudo_bytes(salt, sizeof salt) < 0)
490                                                 goto end;
491                                         /* If -P option then don't bother writing */
492                                         if((printkey != 2)
493                                            && (BIO_write(wbio,magic,
494                                                          sizeof magic-1) != sizeof magic-1
495                                                || BIO_write(wbio,
496                                                             (char *)salt,
497                                                             sizeof salt) != sizeof salt)) {
498                                                 BIO_printf(bio_err,"error writing output file\n");
499                                                 goto end;
500                                         }
501                                 } else if(BIO_read(rbio,mbuf,sizeof mbuf) != sizeof mbuf
502                                           || BIO_read(rbio,
503                                                       (unsigned char *)salt,
504                                     sizeof salt) != sizeof salt) {
505                                         BIO_printf(bio_err,"error reading input file\n");
506                                         goto end;
507                                 } else if(memcmp(mbuf,magic,sizeof magic-1)) {
508                                     BIO_printf(bio_err,"bad magic number\n");
509                                     goto end;
510                                 }
511
512                                 sptr = salt;
513                         }
514
515                         EVP_BytesToKey(cipher,dgst,sptr,
516                                 (unsigned char *)str,
517                                 strlen(str),1,key,iv);
518                         /* zero the complete buffer or the string
519                          * passed from the command line
520                          * bug picked up by
521                          * Larry J. Hughes Jr. <hughes@indiana.edu> */
522                         if (str == strbuf)
523                                 OPENSSL_cleanse(str,SIZE);
524                         else
525                                 OPENSSL_cleanse(str,strlen(str));
526                         }
527                 if ((hiv != NULL) && !set_hex(hiv,iv,sizeof iv))
528                         {
529                         BIO_printf(bio_err,"invalid hex iv value\n");
530                         goto end;
531                         }
532                 if ((hiv == NULL) && (str == NULL))
533                         {
534                         /* No IV was explicitly set and no IV was generated
535                          * during EVP_BytesToKey. Hence the IV is undefined,
536                          * making correct decryption impossible. */
537                         BIO_printf(bio_err, "iv undefined\n");
538                         goto end;
539                         }
540                 if ((hkey != NULL) && !set_hex(hkey,key,sizeof key))
541                         {
542                         BIO_printf(bio_err,"invalid hex key value\n");
543                         goto end;
544                         }
545
546                 if ((benc=BIO_new(BIO_f_cipher())) == NULL)
547                         goto end;
548
549                 /* Since we may be changing parameters work on the encryption
550                  * context rather than calling BIO_set_cipher().
551                  */
552
553                 BIO_get_cipher_ctx(benc, &ctx);
554                 if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, enc))
555                         {
556                         BIO_printf(bio_err, "Error setting cipher %s\n",
557                                 EVP_CIPHER_name(cipher));
558                         ERR_print_errors(bio_err);
559                         goto end;
560                         }
561
562                 if (nopad)
563                         EVP_CIPHER_CTX_set_padding(ctx, 0);
564
565                 if (!EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, enc))
566                         {
567                         BIO_printf(bio_err, "Error setting cipher %s\n",
568                                 EVP_CIPHER_name(cipher));
569                         ERR_print_errors(bio_err);
570                         goto end;
571                         }
572
573                 if (debug)
574                         {
575                         BIO_set_callback(benc,BIO_debug_callback);
576                         BIO_set_callback_arg(benc,(char *)bio_err);
577                         }
578
579                 if (printkey)
580                         {
581                         if (!nosalt)
582                                 {
583                                 printf("salt=");
584                                 for (i=0; i<(int)sizeof(salt); i++)
585                                         printf("%02X",salt[i]);
586                                 printf("\n");
587                                 }
588                         if (cipher->key_len > 0)
589                                 {
590                                 printf("key=");
591                                 for (i=0; i<cipher->key_len; i++)
592                                         printf("%02X",key[i]);
593                                 printf("\n");
594                                 }
595                         if (cipher->iv_len > 0)
596                                 {
597                                 printf("iv =");
598                                 for (i=0; i<cipher->iv_len; i++)
599                                         printf("%02X",iv[i]);
600                                 printf("\n");
601                                 }
602                         if (printkey == 2)
603                                 {
604                                 ret=0;
605                                 goto end;
606                                 }
607                         }
608                 }
609
610         /* Only encrypt/decrypt as we write the file */
611         if (benc != NULL)
612                 wbio=BIO_push(benc,wbio);
613
614         for (;;)
615                 {
616                 inl=BIO_read(rbio,(char *)buff,bsize);
617                 if (inl <= 0) break;
618                 if (BIO_write(wbio,(char *)buff,inl) != inl)
619                         {
620                         BIO_printf(bio_err,"error writing output file\n");
621                         goto end;
622                         }
623                 }
624         if (!BIO_flush(wbio))
625                 {
626                 BIO_printf(bio_err,"bad decrypt\n");
627                 goto end;
628                 }
629
630         ret=0;
631         if (verbose)
632                 {
633                 BIO_printf(bio_err,"bytes read   :%8ld\n",BIO_number_read(in));
634                 BIO_printf(bio_err,"bytes written:%8ld\n",BIO_number_written(out));
635                 }
636 end:
637         ERR_print_errors(bio_err);
638         if (strbuf != NULL) OPENSSL_free(strbuf);
639         if (buff != NULL) OPENSSL_free(buff);
640         if (in != NULL) BIO_free(in);
641         if (out != NULL) BIO_free_all(out);
642         if (benc != NULL) BIO_free(benc);
643         if (b64 != NULL) BIO_free(b64);
644         if(pass) OPENSSL_free(pass);
645         apps_shutdown();
646         OPENSSL_EXIT(ret);
647         }
648
649 int set_hex(char *in, unsigned char *out, int size)
650         {
651         int i,n;
652         unsigned char j;
653
654         n=strlen(in);
655         if (n > (size*2))
656                 {
657                 BIO_printf(bio_err,"hex string is too long\n");
658                 return(0);
659                 }
660         memset(out,0,size);
661         for (i=0; i<n; i++)
662                 {
663                 j=(unsigned char)*in;
664                 *(in++)='\0';
665                 if (j == 0) break;
666                 if ((j >= '0') && (j <= '9'))
667                         j-='0';
668                 else if ((j >= 'A') && (j <= 'F'))
669                         j=j-'A'+10;
670                 else if ((j >= 'a') && (j <= 'f'))
671                         j=j-'a'+10;
672                 else
673                         {
674                         BIO_printf(bio_err,"non-hex digit\n");
675                         return(0);
676                         }
677                 if (i&1)
678                         out[i/2]|=j;
679                 else
680                         out[i/2]=(j<<4);
681                 }
682         return(1);
683         }