crypto/comp/c_zlib.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <openssl/objects.h>
   5 #include <openssl/comp.h>
   6 #include <openssl/err.h>
   7
   8 COMP_METHOD *COMP_zlib(void);
   9
  10 static COMP_METHOD zlib_method_nozlib = {
  11     NID_undef,
  12     "(undef)",
  13     NULL,
  14     NULL,
  15     NULL,
  16     NULL,
  17     NULL,
  18     NULL,
  19 };
  20
  21 #ifndef ZLIB
  22 # undef ZLIB_SHARED
  23 #else
  24
  25 # include <zlib.h>
  26
  27 static int zlib_stateful_init(COMP_CTX *ctx);
  28 static void zlib_stateful_finish(COMP_CTX *ctx);
  29 static int zlib_stateful_compress_block(COMP_CTX *ctx, unsigned char *out,
  30                                         unsigned int olen, unsigned char *in,
  31                                         unsigned int ilen);
  32 static int zlib_stateful_expand_block(COMP_CTX *ctx, unsigned char *out,
  33                                       unsigned int olen, unsigned char *in,
  34                                       unsigned int ilen);
  35
  36 /* memory allocations functions for zlib intialization */
  37 static void *zlib_zalloc(void *opaque, unsigned int no, unsigned int size)
  38 {
  39     void *p;
  40
  41     p = OPENSSL_malloc(no * size);
  42     if (p)
  43         memset(p, 0, no * size);
  44     return p;
  45 }
  46
  47 static void zlib_zfree(void *opaque, void *address)
  48 {
  49     OPENSSL_free(address);
  50 }
  51
  52 # if 0
  53 static int zlib_compress_block(COMP_CTX *ctx, unsigned char *out,
  54                                unsigned int olen, unsigned char *in,
  55                                unsigned int ilen);
  56 static int zlib_expand_block(COMP_CTX *ctx, unsigned char *out,
  57                              unsigned int olen, unsigned char *in,
  58                              unsigned int ilen);
  59
  60 static int zz_uncompress(Bytef *dest, uLongf * destLen, const Bytef *source,
  61                          uLong sourceLen);
  62
  63 static COMP_METHOD zlib_stateless_method = {
  64     NID_zlib_compression,
  65     LN_zlib_compression,
  66     NULL,
  67     NULL,
  68     zlib_compress_block,
  69     zlib_expand_block,
  70     NULL,
  71     NULL,
  72 };
  73 # endif
  74
  75 static COMP_METHOD zlib_stateful_method = {
  76     NID_zlib_compression,
  77     LN_zlib_compression,
  78     zlib_stateful_init,
  79     zlib_stateful_finish,
  80     zlib_stateful_compress_block,
  81     zlib_stateful_expand_block,
  82     NULL,
  83     NULL,
  84 };
  85
  86 /*
  87  * When OpenSSL is built on Windows, we do not want to require that
  88  * the ZLIB.DLL be available in order for the OpenSSL DLLs to
  89  * work.  Therefore, all ZLIB routines are loaded at run time
  90  * and we do not link to a .LIB file when ZLIB_SHARED is set.
  91  */
  92 # if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
  93 #  include <windows.h>
  94 # endif                         /* !(OPENSSL_SYS_WINDOWS ||
  95                                  * OPENSSL_SYS_WIN32) */
  96
  97 # ifdef ZLIB_SHARED
  98 #  include <openssl/dso.h>
  99
 100 /* Function pointers */
 101 typedef int (*compress_ft) (Bytef *dest, uLongf * destLen,
 102                             const Bytef *source, uLong sourceLen);
 103 typedef int (*inflateEnd_ft) (z_streamp strm);
 104 typedef int (*inflate_ft) (z_streamp strm, int flush);
 105 typedef int (*inflateInit__ft) (z_streamp strm,
 106                                 const char *version, int stream_size);
 107 typedef int (*deflateEnd_ft) (z_streamp strm);
 108 typedef int (*deflate_ft) (z_streamp strm, int flush);
 109 typedef int (*deflateInit__ft) (z_streamp strm, int level,
 110                                 const char *version, int stream_size);
 111 typedef const char *(*zError__ft) (int err);
 112 static compress_ft p_compress = NULL;
 113 static inflateEnd_ft p_inflateEnd = NULL;
 114 static inflate_ft p_inflate = NULL;
 115 static inflateInit__ft p_inflateInit_ = NULL;
 116 static deflateEnd_ft p_deflateEnd = NULL;
 117 static deflate_ft p_deflate = NULL;
 118 static deflateInit__ft p_deflateInit_ = NULL;
 119 static zError__ft p_zError = NULL;
 120
 121 static int zlib_loaded = 0;     /* only attempt to init func pts once */
 122 static DSO *zlib_dso = NULL;
 123
 124 #  define compress                p_compress
 125 #  define inflateEnd              p_inflateEnd
 126 #  define inflate                 p_inflate
 127 #  define inflateInit_            p_inflateInit_
 128 #  define deflateEnd              p_deflateEnd
 129 #  define deflate                 p_deflate
 130 #  define deflateInit_            p_deflateInit_
 131 #  define zError                  p_zError
 132 # endif                         /* ZLIB_SHARED */
 133
 134 struct zlib_state {
 135     z_stream istream;
 136     z_stream ostream;
 137 };
 138
 139 static int zlib_stateful_ex_idx = -1;
 140
 141 static int zlib_stateful_init(COMP_CTX *ctx)
 142 {
 143     int err;
 144     struct zlib_state *state =
 145         (struct zlib_state *)OPENSSL_malloc(sizeof(struct zlib_state));
 146
 147     if (state == NULL)
 148         goto err;
 149
 150     state->istream.zalloc = zlib_zalloc;
 151     state->istream.zfree = zlib_zfree;
 152     state->istream.opaque = Z_NULL;
 153     state->istream.next_in = Z_NULL;
 154     state->istream.next_out = Z_NULL;
 155     state->istream.avail_in = 0;
 156     state->istream.avail_out = 0;
 157     err = inflateInit_(&state->istream, ZLIB_VERSION, sizeof(z_stream));
 158     if (err != Z_OK)
 159         goto err;
 160
 161     state->ostream.zalloc = zlib_zalloc;
 162     state->ostream.zfree = zlib_zfree;
 163     state->ostream.opaque = Z_NULL;
 164     state->ostream.next_in = Z_NULL;
 165     state->ostream.next_out = Z_NULL;
 166     state->ostream.avail_in = 0;
 167     state->ostream.avail_out = 0;
 168     err = deflateInit_(&state->ostream, Z_DEFAULT_COMPRESSION,
 169                        ZLIB_VERSION, sizeof(z_stream));
 170     if (err != Z_OK)
 171         goto err;
 172
 173     CRYPTO_new_ex_data(CRYPTO_EX_INDEX_COMP, ctx, &ctx->ex_data);
 174     CRYPTO_set_ex_data(&ctx->ex_data, zlib_stateful_ex_idx, state);
 175     return 1;
 176  err:
 177     if (state)
 178         OPENSSL_free(state);
 179     return 0;
 180 }
 181
 182 static void zlib_stateful_finish(COMP_CTX *ctx)
 183 {
 184     struct zlib_state *state =
 185         (struct zlib_state *)CRYPTO_get_ex_data(&ctx->ex_data,
 186                                                 zlib_stateful_ex_idx);
 187     inflateEnd(&state->istream);
 188     deflateEnd(&state->ostream);
 189     OPENSSL_free(state);
 190     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_COMP, ctx, &ctx->ex_data);
 191 }
 192
 193 static int zlib_stateful_compress_block(COMP_CTX *ctx, unsigned char *out,
 194                                         unsigned int olen, unsigned char *in,
 195                                         unsigned int ilen)
 196 {
 197     int err = Z_OK;
 198     struct zlib_state *state =
 199         (struct zlib_state *)CRYPTO_get_ex_data(&ctx->ex_data,
 200                                                 zlib_stateful_ex_idx);
 201
 202     if (state == NULL)
 203         return -1;
 204
 205     state->ostream.next_in = in;
 206     state->ostream.avail_in = ilen;
 207     state->ostream.next_out = out;
 208     state->ostream.avail_out = olen;
 209     if (ilen > 0)
 210         err = deflate(&state->ostream, Z_SYNC_FLUSH);
 211     if (err != Z_OK)
 212         return -1;
 213 # ifdef DEBUG_ZLIB
 214     fprintf(stderr, "compress(%4d)->%4d %s\n",
 215             ilen, olen - state->ostream.avail_out,
 216             (ilen != olen - state->ostream.avail_out) ? "zlib" : "clear");
 217 # endif
 218     return olen - state->ostream.avail_out;
 219 }
 220
 221 static int zlib_stateful_expand_block(COMP_CTX *ctx, unsigned char *out,
 222                                       unsigned int olen, unsigned char *in,
 223                                       unsigned int ilen)
 224 {
 225     int err = Z_OK;
 226
 227     struct zlib_state *state =
 228         (struct zlib_state *)CRYPTO_get_ex_data(&ctx->ex_data,
 229                                                 zlib_stateful_ex_idx);
 230
 231     if (state == NULL)
 232         return 0;
 233
 234     state->istream.next_in = in;
 235     state->istream.avail_in = ilen;
 236     state->istream.next_out = out;
 237     state->istream.avail_out = olen;
 238     if (ilen > 0)
 239         err = inflate(&state->istream, Z_SYNC_FLUSH);
 240     if (err != Z_OK)
 241         return -1;
 242 # ifdef DEBUG_ZLIB
 243     fprintf(stderr, "expand(%4d)->%4d %s\n",
 244             ilen, olen - state->istream.avail_out,
 245             (ilen != olen - state->istream.avail_out) ? "zlib" : "clear");
 246 # endif
 247     return olen - state->istream.avail_out;
 248 }
 249
 250 # if 0
 251 static int zlib_compress_block(COMP_CTX *ctx, unsigned char *out,
 252                                unsigned int olen, unsigned char *in,
 253                                unsigned int ilen)
 254 {
 255     unsigned long l;
 256     int i;
 257     int clear = 1;
 258
 259     if (ilen > 128) {
 260         out[0] = 1;
 261         l = olen - 1;
 262         i = compress(&(out[1]), &l, in, (unsigned long)ilen);
 263         if (i != Z_OK)
 264             return (-1);
 265         if (ilen > l) {
 266             clear = 0;
 267             l++;
 268         }
 269     }
 270     if (clear) {
 271         out[0] = 0;
 272         memcpy(&(out[1]), in, ilen);
 273         l = ilen + 1;
 274     }
 275 #  ifdef DEBUG_ZLIB
 276     fprintf(stderr, "compress(%4d)->%4d %s\n",
 277             ilen, (int)l, (clear) ? "clear" : "zlib");
 278 #  endif
 279     return ((int)l);
 280 }
 281
 282 static int zlib_expand_block(COMP_CTX *ctx, unsigned char *out,
 283                              unsigned int olen, unsigned char *in,
 284                              unsigned int ilen)
 285 {
 286     unsigned long l;
 287     int i;
 288
 289     if (in[0]) {
 290         l = olen;
 291         i = zz_uncompress(out, &l, &(in[1]), (unsigned long)ilen - 1);
 292         if (i != Z_OK)
 293             return (-1);
 294     } else {
 295         memcpy(out, &(in[1]), ilen - 1);
 296         l = ilen - 1;
 297     }
 298 #  ifdef DEBUG_ZLIB
 299     fprintf(stderr, "expand  (%4d)->%4d %s\n",
 300             ilen, (int)l, in[0] ? "zlib" : "clear");
 301 #  endif
 302     return ((int)l);
 303 }
 304
 305 static int zz_uncompress(Bytef *dest, uLongf * destLen, const Bytef *source,
 306                          uLong sourceLen)
 307 {
 308     z_stream stream;
 309     int err;
 310
 311     stream.next_in = (Bytef *)source;
 312     stream.avail_in = (uInt) sourceLen;
 313     /* Check for source > 64K on 16-bit machine: */
 314     if ((uLong) stream.avail_in != sourceLen)
 315         return Z_BUF_ERROR;
 316
 317     stream.next_out = dest;
 318     stream.avail_out = (uInt) * destLen;
 319     if ((uLong) stream.avail_out != *destLen)
 320         return Z_BUF_ERROR;
 321
 322     stream.zalloc = (alloc_func) 0;
 323     stream.zfree = (free_func) 0;
 324
 325     err = inflateInit_(&stream, ZLIB_VERSION, sizeof(z_stream));
 326     if (err != Z_OK)
 327         return err;
 328
 329     err = inflate(&stream, Z_FINISH);
 330     if (err != Z_STREAM_END) {
 331         inflateEnd(&stream);
 332         return err;
 333     }
 334     *destLen = stream.total_out;
 335
 336     err = inflateEnd(&stream);
 337     return err;
 338 }
 339 # endif
 340
 341 #endif
 342
 343 COMP_METHOD *COMP_zlib(void)
 344 {
 345     COMP_METHOD *meth = &zlib_method_nozlib;
 346
 347 #ifdef ZLIB_SHARED
 348     if (!zlib_loaded) {
 349 # if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
 350         zlib_dso = DSO_load(NULL, "ZLIB1", NULL, 0);
 351 # else
 352         zlib_dso = DSO_load(NULL, "z", NULL, 0);
 353 # endif
 354         if (zlib_dso != NULL) {
 355             p_compress = (compress_ft) DSO_bind_func(zlib_dso, "compress");
 356             p_inflateEnd
 357                 = (inflateEnd_ft) DSO_bind_func(zlib_dso, "inflateEnd");
 358             p_inflate = (inflate_ft) DSO_bind_func(zlib_dso, "inflate");
 359             p_inflateInit_
 360                 = (inflateInit__ft) DSO_bind_func(zlib_dso, "inflateInit_");
 361             p_deflateEnd
 362                 = (deflateEnd_ft) DSO_bind_func(zlib_dso, "deflateEnd");
 363             p_deflate = (deflate_ft) DSO_bind_func(zlib_dso, "deflate");
 364             p_deflateInit_
 365                 = (deflateInit__ft) DSO_bind_func(zlib_dso, "deflateInit_");
 366             p_zError = (zError__ft) DSO_bind_func(zlib_dso, "zError");
 367
 368             if (p_compress && p_inflateEnd && p_inflate
 369                 && p_inflateInit_ && p_deflateEnd
 370                 && p_deflate && p_deflateInit_ && p_zError)
 371                 zlib_loaded++;
 372         }
 373     }
 374 #endif
 375 #ifdef ZLIB_SHARED
 376     if (zlib_loaded)
 377 #endif
 378 #if defined(ZLIB) || defined(ZLIB_SHARED)
 379     {
 380         /*
 381          * init zlib_stateful_ex_idx here so that in a multi-process
 382          * application it's enough to intialize openssl before forking (idx
 383          * will be inherited in all the children)
 384          */
 385         if (zlib_stateful_ex_idx == -1) {
 386             CRYPTO_w_lock(CRYPTO_LOCK_COMP);
 387             if (zlib_stateful_ex_idx == -1)
 388                 zlib_stateful_ex_idx =
 389                     CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_COMP,
 390                                             0, NULL, NULL, NULL, NULL);
 391             CRYPTO_w_unlock(CRYPTO_LOCK_COMP);
 392             if (zlib_stateful_ex_idx == -1)
 393                 goto err;
 394         }
 395
 396         meth = &zlib_stateful_method;
 397     }
 398  err:
 399 #endif
 400
 401     return (meth);
 402 }
 403
 404 void COMP_zlib_cleanup(void)
 405 {
 406 #ifdef ZLIB_SHARED
 407     if (zlib_dso)
 408         DSO_free(zlib_dso);
 409 #endif
 410 }
 411
 412 #ifdef ZLIB
 413
 414 /* Zlib based compression/decompression filter BIO */
 415
 416 typedef struct {
 417     unsigned char *ibuf;        /* Input buffer */
 418     int ibufsize;               /* Buffer size */
 419     z_stream zin;               /* Input decompress context */
 420     unsigned char *obuf;        /* Output buffer */
 421     int obufsize;               /* Output buffer size */
 422     unsigned char *optr;        /* Position in output buffer */
 423     int ocount;                 /* Amount of data in output buffer */
 424     int odone;                  /* deflate EOF */
 425     int comp_level;             /* Compression level to use */
 426     z_stream zout;              /* Output compression context */
 427 } BIO_ZLIB_CTX;
 428
 429 # define ZLIB_DEFAULT_BUFSIZE 1024
 430
 431 static int bio_zlib_new(BIO *bi);
 432 static int bio_zlib_free(BIO *bi);
 433 static int bio_zlib_read(BIO *b, char *out, int outl);
 434 static int bio_zlib_write(BIO *b, const char *in, int inl);
 435 static long bio_zlib_ctrl(BIO *b, int cmd, long num, void *ptr);
 436 static long bio_zlib_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp);
 437
 438 static BIO_METHOD bio_meth_zlib = {
 439     BIO_TYPE_COMP,
 440     "zlib",
 441     bio_zlib_write,
 442     bio_zlib_read,
 443     NULL,
 444     NULL,
 445     bio_zlib_ctrl,
 446     bio_zlib_new,
 447     bio_zlib_free,
 448     bio_zlib_callback_ctrl
 449 };
 450
 451 BIO_METHOD *BIO_f_zlib(void)
 452 {
 453     return &bio_meth_zlib;
 454 }
 455
 456 static int bio_zlib_new(BIO *bi)
 457 {
 458     BIO_ZLIB_CTX *ctx;
 459 # ifdef ZLIB_SHARED
 460     (void)COMP_zlib();
 461     if (!zlib_loaded) {
 462         COMPerr(COMP_F_BIO_ZLIB_NEW, COMP_R_ZLIB_NOT_SUPPORTED);
 463         return 0;
 464     }
 465 # endif
 466     ctx = OPENSSL_malloc(sizeof(BIO_ZLIB_CTX));
 467     if (!ctx) {
 468         COMPerr(COMP_F_BIO_ZLIB_NEW, ERR_R_MALLOC_FAILURE);
 469         return 0;
 470     }
 471     ctx->ibuf = NULL;
 472     ctx->obuf = NULL;
 473     ctx->ibufsize = ZLIB_DEFAULT_BUFSIZE;
 474     ctx->obufsize = ZLIB_DEFAULT_BUFSIZE;
 475     ctx->zin.zalloc = Z_NULL;
 476     ctx->zin.zfree = Z_NULL;
 477     ctx->zin.next_in = NULL;
 478     ctx->zin.avail_in = 0;
 479     ctx->zin.next_out = NULL;
 480     ctx->zin.avail_out = 0;
 481     ctx->zout.zalloc = Z_NULL;
 482     ctx->zout.zfree = Z_NULL;
 483     ctx->zout.next_in = NULL;
 484     ctx->zout.avail_in = 0;
 485     ctx->zout.next_out = NULL;
 486     ctx->zout.avail_out = 0;
 487     ctx->odone = 0;
 488     ctx->comp_level = Z_DEFAULT_COMPRESSION;
 489     bi->init = 1;
 490     bi->ptr = (char *)ctx;
 491     bi->flags = 0;
 492     return 1;
 493 }
 494
 495 static int bio_zlib_free(BIO *bi)
 496 {
 497     BIO_ZLIB_CTX *ctx;
 498     if (!bi)
 499         return 0;
 500     ctx = (BIO_ZLIB_CTX *) bi->ptr;
 501     if (ctx->ibuf) {
 502         /* Destroy decompress context */
 503         inflateEnd(&ctx->zin);
 504         OPENSSL_free(ctx->ibuf);
 505     }
 506     if (ctx->obuf) {
 507         /* Destroy compress context */
 508         deflateEnd(&ctx->zout);
 509         OPENSSL_free(ctx->obuf);
 510     }
 511     OPENSSL_free(ctx);
 512     bi->ptr = NULL;
 513     bi->init = 0;
 514     bi->flags = 0;
 515     return 1;
 516 }
 517
 518 static int bio_zlib_read(BIO *b, char *out, int outl)
 519 {
 520     BIO_ZLIB_CTX *ctx;
 521     int ret;
 522     z_stream *zin;
 523     if (!out || !outl)
 524         return 0;
 525     ctx = (BIO_ZLIB_CTX *) b->ptr;
 526     zin = &ctx->zin;
 527     BIO_clear_retry_flags(b);
 528     if (!ctx->ibuf) {
 529         ctx->ibuf = OPENSSL_malloc(ctx->ibufsize);
 530         if (!ctx->ibuf) {
 531             COMPerr(COMP_F_BIO_ZLIB_READ, ERR_R_MALLOC_FAILURE);
 532             return 0;
 533         }
 534         inflateInit(zin);
 535         zin->next_in = ctx->ibuf;
 536         zin->avail_in = 0;
 537     }
 538
 539     /* Copy output data directly to supplied buffer */
 540     zin->next_out = (unsigned char *)out;
 541     zin->avail_out = (unsigned int)outl;
 542     for (;;) {
 543         /* Decompress while data available */
 544         while (zin->avail_in) {
 545             ret = inflate(zin, 0);
 546             if ((ret != Z_OK) && (ret != Z_STREAM_END)) {
 547                 COMPerr(COMP_F_BIO_ZLIB_READ, COMP_R_ZLIB_INFLATE_ERROR);
 548                 ERR_add_error_data(2, "zlib error:", zError(ret));
 549                 return 0;
 550             }
 551             /* If EOF or we've read everything then return */
 552             if ((ret == Z_STREAM_END) || !zin->avail_out)
 553                 return outl - zin->avail_out;
 554         }
 555
 556         /*
 557          * No data in input buffer try to read some in, if an error then
 558          * return the total data read.
 559          */
 560         ret = BIO_read(b->next_bio, ctx->ibuf, ctx->ibufsize);
 561         if (ret <= 0) {
 562             /* Total data read */
 563             int tot = outl - zin->avail_out;
 564             BIO_copy_next_retry(b);
 565             if (ret < 0)
 566                 return (tot > 0) ? tot : ret;
 567             return tot;
 568         }
 569         zin->avail_in = ret;
 570         zin->next_in = ctx->ibuf;
 571     }
 572 }
 573
 574 static int bio_zlib_write(BIO *b, const char *in, int inl)
 575 {
 576     BIO_ZLIB_CTX *ctx;
 577     int ret;
 578     z_stream *zout;
 579     if (!in || !inl)
 580         return 0;
 581     ctx = (BIO_ZLIB_CTX *) b->ptr;
 582     if (ctx->odone)
 583         return 0;
 584     zout = &ctx->zout;
 585     BIO_clear_retry_flags(b);
 586     if (!ctx->obuf) {
 587         ctx->obuf = OPENSSL_malloc(ctx->obufsize);
 588         /* Need error here */
 589         if (!ctx->obuf) {
 590             COMPerr(COMP_F_BIO_ZLIB_WRITE, ERR_R_MALLOC_FAILURE);
 591             return 0;
 592         }
 593         ctx->optr = ctx->obuf;
 594         ctx->ocount = 0;
 595         deflateInit(zout, ctx->comp_level);
 596         zout->next_out = ctx->obuf;
 597         zout->avail_out = ctx->obufsize;
 598     }
 599     /* Obtain input data directly from supplied buffer */
 600     zout->next_in = (void *)in;
 601     zout->avail_in = inl;
 602     for (;;) {
 603         /* If data in output buffer write it first */
 604         while (ctx->ocount) {
 605             ret = BIO_write(b->next_bio, ctx->optr, ctx->ocount);
 606             if (ret <= 0) {
 607                 /* Total data written */
 608                 int tot = inl - zout->avail_in;
 609                 BIO_copy_next_retry(b);
 610                 if (ret < 0)
 611                     return (tot > 0) ? tot : ret;
 612                 return tot;
 613             }
 614             ctx->optr += ret;
 615             ctx->ocount -= ret;
 616         }
 617
 618         /* Have we consumed all supplied data? */
 619         if (!zout->avail_in)
 620             return inl;
 621
 622         /* Compress some more */
 623
 624         /* Reset buffer */
 625         ctx->optr = ctx->obuf;
 626         zout->next_out = ctx->obuf;
 627         zout->avail_out = ctx->obufsize;
 628         /* Compress some more */
 629         ret = deflate(zout, 0);
 630         if (ret != Z_OK) {
 631             COMPerr(COMP_F_BIO_ZLIB_WRITE, COMP_R_ZLIB_DEFLATE_ERROR);
 632             ERR_add_error_data(2, "zlib error:", zError(ret));
 633             return 0;
 634         }
 635         ctx->ocount = ctx->obufsize - zout->avail_out;
 636     }
 637 }
 638
 639 static int bio_zlib_flush(BIO *b)
 640 {
 641     BIO_ZLIB_CTX *ctx;
 642     int ret;
 643     z_stream *zout;
 644     ctx = (BIO_ZLIB_CTX *) b->ptr;
 645     /* If no data written or already flush show success */
 646     if (!ctx->obuf || (ctx->odone && !ctx->ocount))
 647         return 1;
 648     zout = &ctx->zout;
 649     BIO_clear_retry_flags(b);
 650     /* No more input data */
 651     zout->next_in = NULL;
 652     zout->avail_in = 0;
 653     for (;;) {
 654         /* If data in output buffer write it first */
 655         while (ctx->ocount) {
 656             ret = BIO_write(b->next_bio, ctx->optr, ctx->ocount);
 657             if (ret <= 0) {
 658                 BIO_copy_next_retry(b);
 659                 return ret;
 660             }
 661             ctx->optr += ret;
 662             ctx->ocount -= ret;
 663         }
 664         if (ctx->odone)
 665             return 1;
 666
 667         /* Compress some more */
 668
 669         /* Reset buffer */
 670         ctx->optr = ctx->obuf;
 671         zout->next_out = ctx->obuf;
 672         zout->avail_out = ctx->obufsize;
 673         /* Compress some more */
 674         ret = deflate(zout, Z_FINISH);
 675         if (ret == Z_STREAM_END)
 676             ctx->odone = 1;
 677         else if (ret != Z_OK) {
 678             COMPerr(COMP_F_BIO_ZLIB_FLUSH, COMP_R_ZLIB_DEFLATE_ERROR);
 679             ERR_add_error_data(2, "zlib error:", zError(ret));
 680             return 0;
 681         }
 682         ctx->ocount = ctx->obufsize - zout->avail_out;
 683     }
 684 }
 685
 686 static long bio_zlib_ctrl(BIO *b, int cmd, long num, void *ptr)
 687 {
 688     BIO_ZLIB_CTX *ctx;
 689     int ret, *ip;
 690     int ibs, obs;
 691     if (!b->next_bio)
 692         return 0;
 693     ctx = (BIO_ZLIB_CTX *) b->ptr;
 694     switch (cmd) {
 695
 696     case BIO_CTRL_RESET:
 697         ctx->ocount = 0;
 698         ctx->odone = 0;
 699         ret = 1;
 700         break;
 701
 702     case BIO_CTRL_FLUSH:
 703         ret = bio_zlib_flush(b);
 704         if (ret > 0)
 705             ret = BIO_flush(b->next_bio);
 706         break;
 707
 708     case BIO_C_SET_BUFF_SIZE:
 709         ibs = -1;
 710         obs = -1;
 711         if (ptr != NULL) {
 712             ip = ptr;
 713             if (*ip == 0)
 714                 ibs = (int)num;
 715             else
 716                 obs = (int)num;
 717         } else {
 718             ibs = (int)num;
 719             obs = ibs;
 720         }
 721
 722         if (ibs != -1) {
 723             if (ctx->ibuf) {
 724                 OPENSSL_free(ctx->ibuf);
 725                 ctx->ibuf = NULL;
 726             }
 727             ctx->ibufsize = ibs;
 728         }
 729
 730         if (obs != -1) {
 731             if (ctx->obuf) {
 732                 OPENSSL_free(ctx->obuf);
 733                 ctx->obuf = NULL;
 734             }
 735             ctx->obufsize = obs;
 736         }
 737         ret = 1;
 738         break;
 739
 740     case BIO_C_DO_STATE_MACHINE:
 741         BIO_clear_retry_flags(b);
 742         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 743         BIO_copy_next_retry(b);
 744         break;
 745
 746     default:
 747         ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
 748         break;
 749
 750     }
 751
 752     return ret;
 753 }
 754
 755 static long bio_zlib_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
 756 {
 757     if (!b->next_bio)
 758         return 0;
 759     return BIO_callback_ctrl(b->next_bio, cmd, fp);
 760 }
 761
 762 #endif