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 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 bi->num = 0;
131 return(1);
132 }
133
b64_free(BIO * a)134 static int b64_free(BIO *a)
135 {
136 if (a == NULL) return(0);
137 OPENSSL_free(a->ptr);
138 a->ptr=NULL;
139 a->init=0;
140 a->flags=0;
141 return(1);
142 }
143
b64_read(BIO * b,char * out,int outl)144 static int b64_read(BIO *b, char *out, int outl)
145 {
146 int ret=0,i,ii,j,k,x,n,num,ret_code=0;
147 BIO_B64_CTX *ctx;
148 unsigned char *p,*q;
149
150 if (out == NULL) return(0);
151 ctx=(BIO_B64_CTX *)b->ptr;
152
153 if ((ctx == NULL) || (b->next_bio == NULL)) return(0);
154
155 BIO_clear_retry_flags(b);
156
157 if (ctx->encode != B64_DECODE)
158 {
159 ctx->encode=B64_DECODE;
160 ctx->buf_len=0;
161 ctx->buf_off=0;
162 ctx->tmp_len=0;
163 EVP_DecodeInit(&(ctx->base64));
164 }
165
166 /* First check if there are bytes decoded/encoded */
167 if (ctx->buf_len > 0)
168 {
169 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
170 i=ctx->buf_len-ctx->buf_off;
171 if (i > outl) i=outl;
172 OPENSSL_assert(ctx->buf_off+i < (int)sizeof(ctx->buf));
173 memcpy(out,&(ctx->buf[ctx->buf_off]),i);
174 ret=i;
175 out+=i;
176 outl-=i;
177 ctx->buf_off+=i;
178 if (ctx->buf_len == ctx->buf_off)
179 {
180 ctx->buf_len=0;
181 ctx->buf_off=0;
182 }
183 }
184
185 /* At this point, we have room of outl bytes and an empty
186 * buffer, so we should read in some more. */
187
188 ret_code=0;
189 while (outl > 0)
190 {
191 if (ctx->cont <= 0)
192 break;
193
194 i=BIO_read(b->next_bio,&(ctx->tmp[ctx->tmp_len]),
195 B64_BLOCK_SIZE-ctx->tmp_len);
196
197 if (i <= 0)
198 {
199 ret_code=i;
200
201 /* Should we continue next time we are called? */
202 if (!BIO_should_retry(b->next_bio))
203 {
204 ctx->cont=i;
205 /* If buffer empty break */
206 if(ctx->tmp_len == 0)
207 break;
208 /* Fall through and process what we have */
209 else
210 i = 0;
211 }
212 /* else we retry and add more data to buffer */
213 else
214 break;
215 }
216 i+=ctx->tmp_len;
217 ctx->tmp_len = i;
218
219 /* We need to scan, a line at a time until we
220 * have a valid line if we are starting. */
221 if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL))
222 {
223 /* ctx->start=1; */
224 ctx->tmp_len=0;
225 }
226 else if (ctx->start)
227 {
228 q=p=(unsigned char *)ctx->tmp;
229 for (j=0; j<i; j++)
230 {
231 if (*(q++) != '\n') continue;
232
233 /* due to a previous very long line,
234 * we need to keep on scanning for a '\n'
235 * before we even start looking for
236 * base64 encoded stuff. */
237 if (ctx->tmp_nl)
238 {
239 p=q;
240 ctx->tmp_nl=0;
241 continue;
242 }
243
244 k=EVP_DecodeUpdate(&(ctx->base64),
245 (unsigned char *)ctx->buf,
246 &num,p,q-p);
247 if ((k <= 0) && (num == 0) && (ctx->start))
248 EVP_DecodeInit(&ctx->base64);
249 else
250 {
251 if (p != (unsigned char *)
252 &(ctx->tmp[0]))
253 {
254 i-=(p- (unsigned char *)
255 &(ctx->tmp[0]));
256 for (x=0; x < i; x++)
257 ctx->tmp[x]=p[x];
258 }
259 EVP_DecodeInit(&ctx->base64);
260 ctx->start=0;
261 break;
262 }
263 p=q;
264 }
265
266 /* we fell off the end without starting */
267 if (j == i)
268 {
269 /* Is this is one long chunk?, if so, keep on
270 * reading until a new line. */
271 if (p == (unsigned char *)&(ctx->tmp[0]))
272 {
273 /* Check buffer full */
274 if (i == B64_BLOCK_SIZE)
275 {
276 ctx->tmp_nl=1;
277 ctx->tmp_len=0;
278 }
279 }
280 else if (p != q) /* finished on a '\n' */
281 {
282 n=q-p;
283 for (ii=0; ii<n; ii++)
284 ctx->tmp[ii]=p[ii];
285 ctx->tmp_len=n;
286 }
287 /* else finished on a '\n' */
288 continue;
289 }
290 else
291 {
292 ctx->tmp_len=0;
293 }
294 }
295 else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0))
296 {
297 /* If buffer isn't full and we can retry then
298 * restart to read in more data.
299 */
300 continue;
301 }
302
303 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
304 {
305 int z,jj;
306
307 #if 0
308 jj=(i>>2)<<2;
309 #else
310 jj = i & ~3; /* process per 4 */
311 #endif
312 z=EVP_DecodeBlock((unsigned char *)ctx->buf,
313 (unsigned char *)ctx->tmp,jj);
314 if (jj > 2)
315 {
316 if (ctx->tmp[jj-1] == '=')
317 {
318 z--;
319 if (ctx->tmp[jj-2] == '=')
320 z--;
321 }
322 }
323 /* z is now number of output bytes and jj is the
324 * number consumed */
325 if (jj != i)
326 {
327 memmove(ctx->tmp, &ctx->tmp[jj], i-jj);
328 ctx->tmp_len=i-jj;
329 }
330 ctx->buf_len=0;
331 if (z > 0)
332 {
333 ctx->buf_len=z;
334 }
335 i=z;
336 }
337 else
338 {
339 i=EVP_DecodeUpdate(&(ctx->base64),
340 (unsigned char *)ctx->buf,&ctx->buf_len,
341 (unsigned char *)ctx->tmp,i);
342 ctx->tmp_len = 0;
343 }
344 ctx->buf_off=0;
345 if (i < 0)
346 {
347 ret_code=0;
348 ctx->buf_len=0;
349 break;
350 }
351
352 if (ctx->buf_len <= outl)
353 i=ctx->buf_len;
354 else
355 i=outl;
356
357 memcpy(out,ctx->buf,i);
358 ret+=i;
359 ctx->buf_off=i;
360 if (ctx->buf_off == ctx->buf_len)
361 {
362 ctx->buf_len=0;
363 ctx->buf_off=0;
364 }
365 outl-=i;
366 out+=i;
367 }
368 /* BIO_clear_retry_flags(b); */
369 BIO_copy_next_retry(b);
370 return((ret == 0)?ret_code:ret);
371 }
372
b64_write(BIO * b,const char * in,int inl)373 static int b64_write(BIO *b, const char *in, int inl)
374 {
375 int ret=0;
376 int n;
377 int i;
378 BIO_B64_CTX *ctx;
379
380 ctx=(BIO_B64_CTX *)b->ptr;
381 BIO_clear_retry_flags(b);
382
383 if (ctx->encode != B64_ENCODE)
384 {
385 ctx->encode=B64_ENCODE;
386 ctx->buf_len=0;
387 ctx->buf_off=0;
388 ctx->tmp_len=0;
389 EVP_EncodeInit(&(ctx->base64));
390 }
391
392 OPENSSL_assert(ctx->buf_off < (int)sizeof(ctx->buf));
393 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
394 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
395 n=ctx->buf_len-ctx->buf_off;
396 while (n > 0)
397 {
398 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
399 if (i <= 0)
400 {
401 BIO_copy_next_retry(b);
402 return(i);
403 }
404 OPENSSL_assert(i <= n);
405 ctx->buf_off+=i;
406 OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
407 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
408 n-=i;
409 }
410 /* at this point all pending data has been written */
411 ctx->buf_off=0;
412 ctx->buf_len=0;
413
414 if ((in == NULL) || (inl <= 0)) return(0);
415
416 while (inl > 0)
417 {
418 n=(inl > B64_BLOCK_SIZE)?B64_BLOCK_SIZE:inl;
419
420 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
421 {
422 if (ctx->tmp_len > 0)
423 {
424 OPENSSL_assert(ctx->tmp_len <= 3);
425 n=3-ctx->tmp_len;
426 /* There's a theoretical possibility for this */
427 if (n > inl)
428 n=inl;
429 memcpy(&(ctx->tmp[ctx->tmp_len]),in,n);
430 ctx->tmp_len+=n;
431 ret += n;
432 if (ctx->tmp_len < 3)
433 break;
434 ctx->buf_len=EVP_EncodeBlock((unsigned char *)ctx->buf,(unsigned char *)ctx->tmp,ctx->tmp_len);
435 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
436 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
437 /* Since we're now done using the temporary
438 buffer, the length should be 0'd */
439 ctx->tmp_len=0;
440 }
441 else
442 {
443 if (n < 3)
444 {
445 memcpy(ctx->tmp,in,n);
446 ctx->tmp_len=n;
447 ret += n;
448 break;
449 }
450 n-=n%3;
451 ctx->buf_len=EVP_EncodeBlock((unsigned char *)ctx->buf,(const unsigned char *)in,n);
452 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
453 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
454 ret += n;
455 }
456 }
457 else
458 {
459 EVP_EncodeUpdate(&(ctx->base64),
460 (unsigned char *)ctx->buf,&ctx->buf_len,
461 (unsigned char *)in,n);
462 OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf));
463 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
464 ret += n;
465 }
466 inl-=n;
467 in+=n;
468
469 ctx->buf_off=0;
470 n=ctx->buf_len;
471 while (n > 0)
472 {
473 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
474 if (i <= 0)
475 {
476 BIO_copy_next_retry(b);
477 return((ret == 0)?i:ret);
478 }
479 OPENSSL_assert(i <= n);
480 n-=i;
481 ctx->buf_off+=i;
482 OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf));
483 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
484 }
485 ctx->buf_len=0;
486 ctx->buf_off=0;
487 }
488 return(ret);
489 }
490
b64_ctrl(BIO * b,int cmd,long num,void * ptr)491 static long b64_ctrl(BIO *b, int cmd, long num, void *ptr)
492 {
493 BIO_B64_CTX *ctx;
494 long ret=1;
495 int i;
496
497 ctx=(BIO_B64_CTX *)b->ptr;
498
499 switch (cmd)
500 {
501 case BIO_CTRL_RESET:
502 ctx->cont=1;
503 ctx->start=1;
504 ctx->encode=B64_NONE;
505 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
506 break;
507 case BIO_CTRL_EOF: /* More to read */
508 if (ctx->cont <= 0)
509 ret=1;
510 else
511 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
512 break;
513 case BIO_CTRL_WPENDING: /* More to write in buffer */
514 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
515 ret=ctx->buf_len-ctx->buf_off;
516 if ((ret == 0) && (ctx->encode != B64_NONE)
517 && (ctx->base64.num != 0))
518 ret=1;
519 else if (ret <= 0)
520 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
521 break;
522 case BIO_CTRL_PENDING: /* More to read in buffer */
523 OPENSSL_assert(ctx->buf_len >= ctx->buf_off);
524 ret=ctx->buf_len-ctx->buf_off;
525 if (ret <= 0)
526 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
527 break;
528 case BIO_CTRL_FLUSH:
529 /* do a final write */
530 again:
531 while (ctx->buf_len != ctx->buf_off)
532 {
533 i=b64_write(b,NULL,0);
534 if (i < 0)
535 return i;
536 }
537 if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)
538 {
539 if (ctx->tmp_len != 0)
540 {
541 ctx->buf_len=EVP_EncodeBlock(
542 (unsigned char *)ctx->buf,
543 (unsigned char *)ctx->tmp,
544 ctx->tmp_len);
545 ctx->buf_off=0;
546 ctx->tmp_len=0;
547 goto again;
548 }
549 }
550 else if (ctx->encode != B64_NONE && ctx->base64.num != 0)
551 {
552 ctx->buf_off=0;
553 EVP_EncodeFinal(&(ctx->base64),
554 (unsigned char *)ctx->buf,
555 &(ctx->buf_len));
556 /* push out the bytes */
557 goto again;
558 }
559 /* Finally flush the underlying BIO */
560 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
561 break;
562
563 case BIO_C_DO_STATE_MACHINE:
564 BIO_clear_retry_flags(b);
565 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
566 BIO_copy_next_retry(b);
567 break;
568
569 case BIO_CTRL_DUP:
570 break;
571 case BIO_CTRL_INFO:
572 case BIO_CTRL_GET:
573 case BIO_CTRL_SET:
574 default:
575 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
576 break;
577 }
578 return(ret);
579 }
580
b64_callback_ctrl(BIO * b,int cmd,bio_info_cb * fp)581 static long b64_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
582 {
583 long ret=1;
584
585 if (b->next_bio == NULL) return(0);
586 switch (cmd)
587 {
588 default:
589 ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
590 break;
591 }
592 return(ret);
593 }
594
b64_puts(BIO * b,const char * str)595 static int b64_puts(BIO *b, const char *str)
596 {
597 return b64_write(b,str,strlen(str));
598 }
599