Move the registration of callback functions to special functions
[openssl.git] / crypto / evp / bio_b64.c
1 /* crypto/evp/bio_b64.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 <errno.h>
61 #include "cryptlib.h"
62 #include <openssl/buffer.h>
63 #include <openssl/evp.h>
64
65 static int b64_write(BIO *h,char *buf,int num);
66 static int b64_read(BIO *h,char *buf,int size);
67 /*static int b64_puts(BIO *h,char *str); */
68 /*static int b64_gets(BIO *h,char *str,int size); */
69 static long b64_ctrl(BIO *h,int cmd,long arg1,char *arg2);
70 static int b64_new(BIO *h);
71 static int b64_free(BIO *data);
72 static long b64_callback_ctrl(BIO *h,int cmd,void (*fp)());
73 #define B64_BLOCK_SIZE  1024
74 #define B64_BLOCK_SIZE2 768
75 #define B64_NONE        0
76 #define B64_ENCODE      1
77 #define B64_DECODE      2
78
79 typedef struct b64_struct
80         {
81         /*BIO *bio; moved to the BIO structure */
82         int buf_len;
83         int buf_off;
84         int tmp_len;            /* used to find the start when decoding */
85         int tmp_nl;             /* If true, scan until '\n' */
86         int encode;
87         int start;              /* have we started decoding yet? */
88         int cont;               /* <= 0 when finished */
89         EVP_ENCODE_CTX base64;
90         char buf[EVP_ENCODE_LENGTH(B64_BLOCK_SIZE)+10];
91         char tmp[B64_BLOCK_SIZE];
92         } BIO_B64_CTX;
93
94 static BIO_METHOD methods_b64=
95         {
96         BIO_TYPE_BASE64,"base64 encoding",
97         b64_write,
98         b64_read,
99         NULL, /* b64_puts, */
100         NULL, /* b64_gets, */
101         b64_ctrl,
102         b64_new,
103         b64_free,
104         b64_callback_ctrl,
105         };
106
107 BIO_METHOD *BIO_f_base64(void)
108         {
109         return(&methods_b64);
110         }
111
112 static int b64_new(BIO *bi)
113         {
114         BIO_B64_CTX *ctx;
115
116         ctx=(BIO_B64_CTX *)Malloc(sizeof(BIO_B64_CTX));
117         if (ctx == NULL) return(0);
118
119         ctx->buf_len=0;
120         ctx->tmp_len=0;
121         ctx->tmp_nl=0;
122         ctx->buf_off=0;
123         ctx->cont=1;
124         ctx->start=1;
125         ctx->encode=0;
126
127         bi->init=1;
128         bi->ptr=(char *)ctx;
129         bi->flags=0;
130         return(1);
131         }
132
133 static int b64_free(BIO *a)
134         {
135         if (a == NULL) return(0);
136         Free(a->ptr);
137         a->ptr=NULL;
138         a->init=0;
139         a->flags=0;
140         return(1);
141         }
142         
143 static int b64_read(BIO *b, char *out, int outl)
144         {
145         int ret=0,i,ii,j,k,x,n,num,ret_code=0;
146         BIO_B64_CTX *ctx;
147         unsigned char *p,*q;
148
149         if (out == NULL) return(0);
150         ctx=(BIO_B64_CTX *)b->ptr;
151
152         if ((ctx == NULL) || (b->next_bio == NULL)) return(0);
153
154         if (ctx->encode != B64_DECODE)
155                 {
156                 ctx->encode=B64_DECODE;
157                 ctx->buf_len=0;
158                 ctx->buf_off=0;
159                 ctx->tmp_len=0;
160                 EVP_DecodeInit(&(ctx->base64));
161                 }
162
163         /* First check if there are bytes decoded/encoded */
164         if (ctx->buf_len > 0)
165                 {
166                 i=ctx->buf_len-ctx->buf_off;
167                 if (i > outl) i=outl;
168                 memcpy(out,&(ctx->buf[ctx->buf_off]),i);
169                 ret=i;
170                 out+=i;
171                 outl-=i;
172                 ctx->buf_off+=i;
173                 if (ctx->buf_len == ctx->buf_off)
174                         {
175                         ctx->buf_len=0;
176                         ctx->buf_off=0;
177                         }
178                 }
179
180         /* At this point, we have room of outl bytes and an empty
181          * buffer, so we should read in some more. */
182
183         ret_code=0;
184         while (outl > 0)
185                 {
186                 if (ctx->cont <= 0) break;
187
188                 i=BIO_read(b->next_bio,&(ctx->tmp[ctx->tmp_len]),
189                         B64_BLOCK_SIZE-ctx->tmp_len);
190
191                 if (i <= 0)
192                         {
193                         ret_code=i;
194
195                         /* Should be continue next time we are called? */
196                         if (!BIO_should_retry(b->next_bio))
197                                 ctx->cont=i;
198                         /* else we should continue when called again */
199                         break;
200                         }
201                 i+=ctx->tmp_len;
202
203                 /* We need to scan, a line at a time until we
204                  * have a valid line if we are starting. */
205                 if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL))
206                         {
207                         /* ctx->start=1; */
208                         ctx->tmp_len=0;
209                         }
210                 else if (ctx->start)
211                         {
212                         q=p=(unsigned char *)ctx->tmp;
213                         for (j=0; j<i; j++)
214                                 {
215                                 if (*(q++) != '\n') continue;
216
217                                 /* due to a previous very long line,
218                                  * we need to keep on scanning for a '\n'
219                                  * before we even start looking for
220                                  * base64 encoded stuff. */
221                                 if (ctx->tmp_nl)
222                                         {
223                                         p=q;
224                                         ctx->tmp_nl=0;
225                                         continue;
226                                         }
227
228                                 k=EVP_DecodeUpdate(&(ctx->base64),
229                                         (unsigned char *)ctx->buf,
230                                         &num,p,q-p);
231                                 if ((k <= 0) && (num == 0) && (ctx->start))
232                                         EVP_DecodeInit(&ctx->base64);
233                                 else 
234                                         {
235                                         if (p != (unsigned char *)
236                                                 &(ctx->tmp[0]))
237                                                 {
238                                                 i-=(p- (unsigned char *)
239                                                         &(ctx->tmp[0]));
240                                                 for (x=0; x < i; x++)
241                                                         ctx->tmp[x]=p[x];
242                                                 }
243                                         EVP_DecodeInit(&ctx->base64);
244                                         ctx->start=0;
245                                         break;
246                                         }
247                                 p=q;
248                                 }
249
250                         /* we fell off the end without starting */
251                         if (j == i)
252                                 {
253                                 /* Is this is one long chunk?, if so, keep on
254                                  * reading until a new line. */
255                                 if (p == (unsigned char *)&(ctx->tmp[0]))
256                                         {
257                                         ctx->tmp_nl=1;
258                                         ctx->tmp_len=0;
259                                         }
260                                 else if (p != q) /* finished on a '\n' */
261                                         {
262                                         n=q-p;
263                                         for (ii=0; ii<n; ii++)
264                                                 ctx->tmp[ii]=p[ii];
265                                         ctx->tmp_len=n;
266                                         }
267                                 /* else finished on a '\n' */
268                                 continue;
269                                 }
270                         else
271                                 ctx->tmp_len=0;
272                         }
273
274                 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
275                         {
276                         int z,jj;
277
278                         jj=(i>>2)<<2;
279                         z=EVP_DecodeBlock((unsigned char *)ctx->buf,
280                                 (unsigned char *)ctx->tmp,jj);
281                         if (jj > 2)
282                                 {
283                                 if (ctx->tmp[jj-1] == '=')
284                                         {
285                                         z--;
286                                         if (ctx->tmp[jj-2] == '=')
287                                                 z--;
288                                         }
289                                 }
290                         /* z is now number of output bytes and jj is the
291                          * number consumed */
292                         if (jj != i)
293                                 {
294                                 memcpy((unsigned char *)ctx->tmp,
295                                         (unsigned char *)&(ctx->tmp[jj]),i-jj);
296                                 ctx->tmp_len=i-jj;
297                                 }
298                         ctx->buf_len=0;
299                         if (z > 0)
300                                 {
301                                 ctx->buf_len=z;
302                                 i=1;
303                                 }
304                         else
305                                 i=z;
306                         }
307                 else
308                         {
309                         i=EVP_DecodeUpdate(&(ctx->base64),
310                                 (unsigned char *)ctx->buf,&ctx->buf_len,
311                                 (unsigned char *)ctx->tmp,i);
312                         }
313                 ctx->cont=i;
314                 ctx->buf_off=0;
315                 if (i < 0)
316                         {
317                         ret_code=0;
318                         ctx->buf_len=0;
319                         break;
320                         }
321
322                 if (ctx->buf_len <= outl)
323                         i=ctx->buf_len;
324                 else
325                         i=outl;
326
327                 memcpy(out,ctx->buf,i);
328                 ret+=i;
329                 ctx->buf_off=i;
330                 if (ctx->buf_off == ctx->buf_len)
331                         {
332                         ctx->buf_len=0;
333                         ctx->buf_off=0;
334                         }
335                 outl-=i;
336                 out+=i;
337                 }
338         BIO_clear_retry_flags(b);
339         BIO_copy_next_retry(b);
340         return((ret == 0)?ret_code:ret);
341         }
342
343 static int b64_write(BIO *b, char *in, int inl)
344         {
345         int ret=inl,n,i;
346         BIO_B64_CTX *ctx;
347
348         ctx=(BIO_B64_CTX *)b->ptr;
349         BIO_clear_retry_flags(b);
350
351         if (ctx->encode != B64_ENCODE)
352                 {
353                 ctx->encode=B64_ENCODE;
354                 ctx->buf_len=0;
355                 ctx->buf_off=0;
356                 ctx->tmp_len=0;
357                 EVP_EncodeInit(&(ctx->base64));
358                 }
359
360         n=ctx->buf_len-ctx->buf_off;
361         while (n > 0)
362                 {
363                 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
364                 if (i <= 0)
365                         {
366                         BIO_copy_next_retry(b);
367                         return(i);
368                         }
369                 ctx->buf_off+=i;
370                 n-=i;
371                 }
372         /* at this point all pending data has been written */
373
374         if ((in == NULL) || (inl <= 0)) return(0);
375
376         ctx->buf_off=0;
377         while (inl > 0)
378                 {
379                 n=(inl > B64_BLOCK_SIZE)?B64_BLOCK_SIZE:inl;
380
381                 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
382                         {
383                         if (ctx->tmp_len > 0)
384                                 {
385                                 n=3-ctx->tmp_len;
386                                 memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);
387                                 ctx->tmp_len+=n;
388                                 n=ctx->tmp_len;
389                                 if (n < 3)
390                                         break;
391                                 ctx->buf_len=EVP_EncodeBlock(
392                                         (unsigned char *)ctx->buf,
393                                         (unsigned char *)ctx->tmp,n);
394                                 }
395                         else
396                                 {
397                                 if (n < 3)
398                                         {
399                                         memcpy(&(ctx->tmp[0]),in,n);
400                                         ctx->tmp_len=n;
401                                         break;
402                                         }
403                                 n-=n%3;
404                                 ctx->buf_len=EVP_EncodeBlock(
405                                         (unsigned char *)ctx->buf,
406                                         (unsigned char *)in,n);
407                                 }
408                         }
409                 else
410                         {
411                         EVP_EncodeUpdate(&(ctx->base64),
412                                 (unsigned char *)ctx->buf,&ctx->buf_len,
413                                 (unsigned char *)in,n);
414                         }
415                 inl-=n;
416                 in+=n;
417
418                 ctx->buf_off=0;
419                 n=ctx->buf_len;
420                 while (n > 0)
421                         {
422                         i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
423                         if (i <= 0)
424                                 {
425                                 BIO_copy_next_retry(b);
426                                 return((ret == 0)?i:ret);
427                                 }
428                         n-=i;
429                         ctx->buf_off+=i;
430                         }
431                 ctx->buf_len=0;
432                 ctx->buf_off=0;
433                 }
434         return(ret);
435         }
436
437 static long b64_ctrl(BIO *b, int cmd, long num, char *ptr)
438         {
439         BIO_B64_CTX *ctx;
440         long ret=1;
441         int i;
442
443         ctx=(BIO_B64_CTX *)b->ptr;
444
445         switch (cmd)
446                 {
447         case BIO_CTRL_RESET:
448                 ctx->cont=1;
449                 ctx->start=1;
450                 ctx->encode=B64_NONE;
451                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
452                 break;
453         case BIO_CTRL_EOF:      /* More to read */
454                 if (ctx->cont <= 0)
455                         ret=1;
456                 else
457                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
458                 break;
459         case BIO_CTRL_WPENDING: /* More to write in buffer */
460                 ret=ctx->buf_len-ctx->buf_off;
461                 if ((ret == 0) && (ctx->base64.num != 0))
462                         ret=1;
463                 else if (ret <= 0)
464                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
465                 break;
466         case BIO_CTRL_PENDING: /* More to read in buffer */
467                 ret=ctx->buf_len-ctx->buf_off;
468                 if (ret <= 0)
469                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
470                 break;
471         case BIO_CTRL_FLUSH:
472                 /* do a final write */
473 again:
474                 while (ctx->buf_len != ctx->buf_off)
475                         {
476                         i=b64_write(b,NULL,0);
477                         if (i < 0)
478                                 {
479                                 ret=i;
480                                 break;
481                                 }
482                         }
483                 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
484                         {
485                         if (ctx->tmp_len != 0)
486                                 {
487                                 ctx->buf_len=EVP_EncodeBlock(
488                                         (unsigned char *)ctx->buf,
489                                         (unsigned char *)ctx->tmp,
490                                         ctx->tmp_len);
491                                 ctx->buf_off=0;
492                                 ctx->tmp_len=0;
493                                 goto again;
494                                 }
495                         }
496                 else if (ctx->base64.num != 0)
497                         {
498                         ctx->buf_off=0;
499                         EVP_EncodeFinal(&(ctx->base64),
500                                 (unsigned char *)ctx->buf,
501                                 &(ctx->buf_len));
502                         /* push out the bytes */
503                         goto again;
504                         }
505                 /* Finally flush the underlying BIO */
506                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
507                 break;
508
509         case BIO_C_DO_STATE_MACHINE:
510                 BIO_clear_retry_flags(b);
511                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
512                 BIO_copy_next_retry(b);
513                 break;
514
515         case BIO_CTRL_DUP:
516                 break;
517         case BIO_CTRL_INFO:
518         case BIO_CTRL_GET:
519         case BIO_CTRL_SET:
520         default:
521                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
522                 break;
523                 }
524         return(ret);
525         }
526
527 static long b64_callback_ctrl(BIO *b, int cmd, void (*fp)())
528         {
529         long ret=1;
530
531         if (b->next_bio == NULL) return(0);
532         switch (cmd)
533                 {
534         default:
535                 ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
536                 break;
537                 }
538         return(ret);
539         }
540