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, const char *buf, int num);
66 static int b64_read(BIO *h, char *buf, int size);
67 /*static int b64_puts(BIO *h, const char *str); */
68 /*static int b64_gets(BIO *h, char *str, int size); */
69 static long b64_ctrl(BIO *h, int cmd, long arg1, void *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,bio_info_cb *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
BIO_f_base64(void)107 BIO_METHOD *BIO_f_base64(void)
108 {
109 return(&methods_b64);
110 }
111
b64_new(BIO * bi)112 static int b64_new(BIO *bi)
113 {
114 BIO_B64_CTX *ctx;
115
116 ctx=(BIO_B64_CTX *)OPENSSL_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
b64_free(BIO * a)133 static int b64_free(BIO *a)
134 {
135 if (a == NULL) return(0);
136 OPENSSL_free(a->ptr);
137 a->ptr=NULL;
138 a->init=0;
139 a->flags=0;
140 return(1);
141 }
142
b64_read(BIO * b,char * out,int outl)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 OPENSSL_assert(ctx->buf_off+i < (int)sizeof(ctx->buf));
169 memcpy(out,&(ctx->buf[ctx->buf_off]),i);
170 ret=i;
171 out+=i;
172 outl-=i;
173 ctx->buf_off+=i;
174 if (ctx->buf_len == ctx->buf_off)
175 {
176 ctx->buf_len=0;
177 ctx->buf_off=0;
178 }
179 }
180
181 /* At this point, we have room of outl bytes and an empty
182 * buffer, so we should read in some more. */
183
184 ret_code=0;
185 while (outl > 0)
186 {
187
188 if (ctx->cont <= 0)
189 break;
190
191 i=BIO_read(b->next_bio,&(ctx->tmp[ctx->tmp_len]),
192 B64_BLOCK_SIZE-ctx->tmp_len);
193
194 if (i <= 0)
195 {
196 ret_code=i;
197
198 /* Should be continue next time we are called? */
199 if (!BIO_should_retry(b->next_bio))
200 {
201 ctx->cont=i;
202 /* If buffer empty break */
203 if(ctx->tmp_len == 0)
204 break;
205 /* Fall through and process what we have */
206 else
207 i = 0;
208 }
209 /* else we retry and add more data to buffer */
210 else
211 break;
212 }
213 i+=ctx->tmp_len;
214 ctx->tmp_len = i;
215
216 /* We need to scan, a line at a time until we
217 * have a valid line if we are starting. */
218 if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL))
219 {
220 /* ctx->start=1; */
221 ctx->tmp_len=0;
222 }
223 else if (ctx->start)
224 {
225 q=p=(unsigned char *)ctx->tmp;
226 for (j=0; j<i; j++)
227 {
228 if (*(q++) != '\n') continue;
229
230 /* due to a previous very long line,
231 * we need to keep on scanning for a '\n'
232 * before we even start looking for
233 * base64 encoded stuff. */
234 if (ctx->tmp_nl)
235 {
236 p=q;
237 ctx->tmp_nl=0;
238 continue;
239 }
240
241 k=EVP_DecodeUpdate(&(ctx->base64),
242 (unsigned char *)ctx->buf,
243 &num,p,q-p);
244 if ((k <= 0) && (num == 0) && (ctx->start))
245 EVP_DecodeInit(&ctx->base64);
246 else
247 {
248 if (p != (unsigned char *)
249 &(ctx->tmp[0]))
250 {
251 i-=(p- (unsigned char *)
252 &(ctx->tmp[0]));
253 for (x=0; x < i; x++)
254 ctx->tmp[x]=p[x];
255 }
256 EVP_DecodeInit(&ctx->base64);
257 ctx->start=0;
258 break;
259 }
260 p=q;
261 }
262
263 /* we fell off the end without starting */
264 if (j == i)
265 {
266 /* Is this is one long chunk?, if so, keep on
267 * reading until a new line. */
268 if (p == (unsigned char *)&(ctx->tmp[0]))
269 {
270 /* Check buffer full */
271 if (i == B64_BLOCK_SIZE)
272 {
273 ctx->tmp_nl=1;
274 ctx->tmp_len=0;
275 }
276 }
277 else if (p != q) /* finished on a '\n' */
278 {
279 n=q-p;
280 for (ii=0; ii<n; ii++)
281 ctx->tmp[ii]=p[ii];
282 ctx->tmp_len=n;
283 }
284 /* else finished on a '\n' */
285 continue;
286 }
287 else
288 ctx->tmp_len=0;
289 }
290 /* If buffer isn't full and we can retry then
291 * restart to read in more data.
292 */
293 else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))
294 continue;
295
296 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
297 {
298 int z,jj;
299
300 jj=(i>>2)<<2;
301 z=EVP_DecodeBlock((unsigned char *)ctx->buf,
302 (unsigned char *)ctx->tmp,jj);
303 if (jj > 2)
304 {
305 if (ctx->tmp[jj-1] == '=')
306 {
307 z--;
308 if (ctx->tmp[jj-2] == '=')
309 z--;
310 }
311 }
312 /* z is now number of output bytes and jj is the
313 * number consumed */
314 if (jj != i)
315 {
316 memcpy((unsigned char *)ctx->tmp,
317 (unsigned char *)&(ctx->tmp[jj]),i-jj);
318 ctx->tmp_len=i-jj;
319 }
320 ctx->buf_len=0;
321 if (z > 0)
322 {
323 ctx->buf_len=z;
324 i=1;
325 }
326 else
327 i=z;
328 }
329 else
330 {
331 i=EVP_DecodeUpdate(&(ctx->base64),
332 (unsigned char *)ctx->buf,&ctx->buf_len,
333 (unsigned char *)ctx->tmp,i);
334 ctx->tmp_len = 0;
335 }
336 ctx->buf_off=0;
337 if (i < 0)
338 {
339 ret_code=0;
340 ctx->buf_len=0;
341 break;
342 }
343
344 if (ctx->buf_len <= outl)
345 i=ctx->buf_len;
346 else
347 i=outl;
348
349 memcpy(out,ctx->buf,i);
350 ret+=i;
351 ctx->buf_off=i;
352 if (ctx->buf_off == ctx->buf_len)
353 {
354 ctx->buf_len=0;
355 ctx->buf_off=0;
356 }
357 outl-=i;
358 out+=i;
359 }
360 BIO_clear_retry_flags(b);
361 BIO_copy_next_retry(b);
362 return((ret == 0)?ret_code:ret);
363 }
364
b64_write(BIO * b,const char * in,int inl)365 static int b64_write(BIO *b, const char *in, int inl)
366 {
367 int ret=inl,n,i;
368 BIO_B64_CTX *ctx;
369
370 ctx=(BIO_B64_CTX *)b->ptr;
371 BIO_clear_retry_flags(b);
372
373 if (ctx->encode != B64_ENCODE)
374 {
375 ctx->encode=B64_ENCODE;
376 ctx->buf_len=0;
377 ctx->buf_off=0;
378 ctx->tmp_len=0;
379 EVP_EncodeInit(&(ctx->base64));
380 }
381
382 n=ctx->buf_len-ctx->buf_off;
383 while (n > 0)
384 {
385 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
386 if (i <= 0)
387 {
388 BIO_copy_next_retry(b);
389 return(i);
390 }
391 ctx->buf_off+=i;
392 n-=i;
393 }
394 /* at this point all pending data has been written */
395 ctx->buf_off=0;
396 ctx->buf_len=0;
397
398 if ((in == NULL) || (inl <= 0)) return(0);
399
400 while (inl > 0)
401 {
402 n=(inl > B64_BLOCK_SIZE)?B64_BLOCK_SIZE:inl;
403
404 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
405 {
406 if (ctx->tmp_len > 0)
407 {
408 n=3-ctx->tmp_len;
409 /* There's a teoretical possibility for this */
410 if (n > inl)
411 n=inl;
412 memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);
413 ctx->tmp_len+=n;
414 if (ctx->tmp_len < 3)
415 break;
416 ctx->buf_len=EVP_EncodeBlock(
417 (unsigned char *)ctx->buf,
418 (unsigned char *)ctx->tmp,
419 ctx->tmp_len);
420 /* Since we're now done using the temporary
421 buffer, the length should be 0'd */
422 ctx->tmp_len=0;
423 }
424 else
425 {
426 if (n < 3)
427 {
428 memcpy(&(ctx->tmp[0]),in,n);
429 ctx->tmp_len=n;
430 break;
431 }
432 n-=n%3;
433 ctx->buf_len=EVP_EncodeBlock(
434 (unsigned char *)ctx->buf,
435 (unsigned char *)in,n);
436 }
437 }
438 else
439 {
440 EVP_EncodeUpdate(&(ctx->base64),
441 (unsigned char *)ctx->buf,&ctx->buf_len,
442 (unsigned char *)in,n);
443 }
444 inl-=n;
445 in+=n;
446
447 ctx->buf_off=0;
448 n=ctx->buf_len;
449 while (n > 0)
450 {
451 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
452 if (i <= 0)
453 {
454 BIO_copy_next_retry(b);
455 return((ret == 0)?i:ret);
456 }
457 n-=i;
458 ctx->buf_off+=i;
459 }
460 ctx->buf_len=0;
461 ctx->buf_off=0;
462 }
463 return(ret);
464 }
465
b64_ctrl(BIO * b,int cmd,long num,void * ptr)466 static long b64_ctrl(BIO *b, int cmd, long num, void *ptr)
467 {
468 BIO_B64_CTX *ctx;
469 long ret=1;
470 int i;
471
472 ctx=(BIO_B64_CTX *)b->ptr;
473
474 switch (cmd)
475 {
476 case BIO_CTRL_RESET:
477 ctx->cont=1;
478 ctx->start=1;
479 ctx->encode=B64_NONE;
480 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
481 break;
482 case BIO_CTRL_EOF: /* More to read */
483 if (ctx->cont <= 0)
484 ret=1;
485 else
486 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
487 break;
488 case BIO_CTRL_WPENDING: /* More to write in buffer */
489 ret=ctx->buf_len-ctx->buf_off;
490 if ((ret == 0) && (ctx->encode != B64_NONE)
491 && (ctx->base64.num != 0))
492 ret=1;
493 else if (ret <= 0)
494 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
495 break;
496 case BIO_CTRL_PENDING: /* More to read in buffer */
497 ret=ctx->buf_len-ctx->buf_off;
498 if (ret <= 0)
499 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
500 break;
501 case BIO_CTRL_FLUSH:
502 /* do a final write */
503 again:
504 while (ctx->buf_len != ctx->buf_off)
505 {
506 i=b64_write(b,NULL,0);
507 if (i < 0)
508 return i;
509 }
510 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
511 {
512 if (ctx->tmp_len != 0)
513 {
514 ctx->buf_len=EVP_EncodeBlock(
515 (unsigned char *)ctx->buf,
516 (unsigned char *)ctx->tmp,
517 ctx->tmp_len);
518 ctx->buf_off=0;
519 ctx->tmp_len=0;
520 goto again;
521 }
522 }
523 else if (ctx->encode != B64_NONE && ctx->base64.num != 0)
524 {
525 ctx->buf_off=0;
526 EVP_EncodeFinal(&(ctx->base64),
527 (unsigned char *)ctx->buf,
528 &(ctx->buf_len));
529 /* push out the bytes */
530 goto again;
531 }
532 /* Finally flush the underlying BIO */
533 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
534 break;
535
536 case BIO_C_DO_STATE_MACHINE:
537 BIO_clear_retry_flags(b);
538 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
539 BIO_copy_next_retry(b);
540 break;
541
542 case BIO_CTRL_DUP:
543 break;
544 case BIO_CTRL_INFO:
545 case BIO_CTRL_GET:
546 case BIO_CTRL_SET:
547 default:
548 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
549 break;
550 }
551 return(ret);
552 }
553
b64_callback_ctrl(BIO * b,int cmd,bio_info_cb * fp)554 static long b64_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
555 {
556 long ret=1;
557
558 if (b->next_bio == NULL) return(0);
559 switch (cmd)
560 {
561 default:
562 ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
563 break;
564 }
565 return(ret);
566 }
567
568