diff options
Diffstat (limited to 'zlib/inflate.c')
-rw-r--r-- | zlib/inflate.c | 282 |
1 files changed, 197 insertions, 85 deletions
diff --git a/zlib/inflate.c b/zlib/inflate.c index 792fdee..a8431ab 100644 --- a/zlib/inflate.c +++ b/zlib/inflate.c @@ -1,5 +1,5 @@ /* inflate.c -- zlib decompression - * Copyright (C) 1995-2005 Mark Adler + * Copyright (C) 1995-2010 Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -45,7 +45,7 @@ * - Rearrange window copies in inflate_fast() for speed and simplification * - Unroll last copy for window match in inflate_fast() * - Use local copies of window variables in inflate_fast() for speed - * - Pull out common write == 0 case for speed in inflate_fast() + * - Pull out common wnext == 0 case for speed in inflate_fast() * - Make op and len in inflate_fast() unsigned for consistency * - Add FAR to lcode and dcode declarations in inflate_fast() * - Simplified bad distance check in inflate_fast() @@ -117,28 +117,52 @@ z_streamp strm; state->head = Z_NULL; state->wsize = 0; state->whave = 0; - state->write = 0; + state->wnext = 0; state->hold = 0; state->bits = 0; state->lencode = state->distcode = state->next = state->codes; + state->sane = 1; + state->back = -1; Tracev((stderr, "inflate: reset\n")); return Z_OK; } -int ZEXPORT inflatePrime(strm, bits, value) +int ZEXPORT inflateReset2(strm, windowBits) z_streamp strm; -int bits; -int value; +int windowBits; { + int wrap; struct inflate_state FAR *state; + /* get the state */ if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; state = (struct inflate_state FAR *)strm->state; - if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR; - value &= (1L << bits) - 1; - state->hold += value << state->bits; - state->bits += bits; - return Z_OK; + + /* extract wrap request from windowBits parameter */ + if (windowBits < 0) { + wrap = 0; + windowBits = -windowBits; + } + else { + wrap = (windowBits >> 4) + 1; +#ifdef GUNZIP + if (windowBits < 48) + windowBits &= 15; +#endif + } + + /* set number of window bits, free window if different */ + if (windowBits && (windowBits < 8 || windowBits > 15)) + return Z_STREAM_ERROR; + if (state->window != Z_NULL && state->wbits != (unsigned)windowBits) { + ZFREE(strm, state->window); + state->window = Z_NULL; + } + + /* update state and reset the rest of it */ + state->wrap = wrap; + state->wbits = (unsigned)windowBits; + return inflateReset(strm); } int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) @@ -147,6 +171,7 @@ int windowBits; const char *version; int stream_size; { + int ret; struct inflate_state FAR *state; if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || @@ -164,24 +189,13 @@ int stream_size; if (state == Z_NULL) return Z_MEM_ERROR; Tracev((stderr, "inflate: allocated\n")); strm->state = (struct internal_state FAR *)state; - if (windowBits < 0) { - state->wrap = 0; - windowBits = -windowBits; - } - else { - state->wrap = (windowBits >> 4) + 1; -#ifdef GUNZIP - if (windowBits < 48) windowBits &= 15; -#endif - } - if (windowBits < 8 || windowBits > 15) { + state->window = Z_NULL; + ret = inflateReset2(strm, windowBits); + if (ret != Z_OK) { ZFREE(strm, state); strm->state = Z_NULL; - return Z_STREAM_ERROR; } - state->wbits = (unsigned)windowBits; - state->window = Z_NULL; - return inflateReset(strm); + return ret; } int ZEXPORT inflateInit_(strm, version, stream_size) @@ -192,6 +206,27 @@ int stream_size; return inflateInit2_(strm, DEF_WBITS, version, stream_size); } +int ZEXPORT inflatePrime(strm, bits, value) +z_streamp strm; +int bits; +int value; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (bits < 0) { + state->hold = 0; + state->bits = 0; + return Z_OK; + } + if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR; + value &= (1L << bits) - 1; + state->hold += value << state->bits; + state->bits += bits; + return Z_OK; +} + /* Return state with length and distance decoding tables and index sizes set to fixed code decoding. Normally this returns fixed tables from inffixed.h. @@ -340,7 +375,7 @@ unsigned out; /* if window not in use yet, initialize */ if (state->wsize == 0) { state->wsize = 1U << state->wbits; - state->write = 0; + state->wnext = 0; state->whave = 0; } @@ -348,22 +383,22 @@ unsigned out; copy = out - strm->avail_out; if (copy >= state->wsize) { zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); - state->write = 0; + state->wnext = 0; state->whave = state->wsize; } else { - dist = state->wsize - state->write; + dist = state->wsize - state->wnext; if (dist > copy) dist = copy; - zmemcpy(state->window + state->write, strm->next_out - copy, dist); + zmemcpy(state->window + state->wnext, strm->next_out - copy, dist); copy -= dist; if (copy) { zmemcpy(state->window, strm->next_out - copy, copy); - state->write = copy; + state->wnext = copy; state->whave = state->wsize; } else { - state->write += dist; - if (state->write == state->wsize) state->write = 0; + state->wnext += dist; + if (state->wnext == state->wsize) state->wnext = 0; if (state->whave < state->wsize) state->whave += dist; } } @@ -564,7 +599,7 @@ int flush; unsigned in, out; /* save starting available input and output */ unsigned copy; /* number of stored or match bytes to copy */ unsigned char FAR *from; /* where to copy match bytes from */ - code this; /* current decoding table entry */ + code here; /* current decoding table entry */ code last; /* parent table entry */ unsigned len; /* length to copy for repeats, bits to drop */ int ret; /* return code */ @@ -619,7 +654,9 @@ int flush; } DROPBITS(4); len = BITS(4) + 8; - if (len > state->wbits) { + if (state->wbits == 0) + state->wbits = len; + else if (len > state->wbits) { strm->msg = (char *)"invalid window size"; state->mode = BAD; break; @@ -771,7 +808,7 @@ int flush; strm->adler = state->check = adler32(0L, Z_NULL, 0); state->mode = TYPE; case TYPE: - if (flush == Z_BLOCK) goto inf_leave; + if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave; case TYPEDO: if (state->last) { BYTEBITS(); @@ -791,7 +828,11 @@ int flush; fixedtables(state); Tracev((stderr, "inflate: fixed codes block%s\n", state->last ? " (last)" : "")); - state->mode = LEN; /* decode codes */ + state->mode = LEN_; /* decode codes */ + if (flush == Z_TREES) { + DROPBITS(2); + goto inf_leave; + } break; case 2: /* dynamic block */ Tracev((stderr, "inflate: dynamic codes block%s\n", @@ -816,6 +857,9 @@ int flush; Tracev((stderr, "inflate: stored length %u\n", state->length)); INITBITS(); + state->mode = COPY_; + if (flush == Z_TREES) goto inf_leave; + case COPY_: state->mode = COPY; case COPY: copy = state->length; @@ -876,19 +920,19 @@ int flush; case CODELENS: while (state->have < state->nlen + state->ndist) { for (;;) { - this = state->lencode[BITS(state->lenbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if (this.val < 16) { - NEEDBITS(this.bits); - DROPBITS(this.bits); - state->lens[state->have++] = this.val; + if (here.val < 16) { + NEEDBITS(here.bits); + DROPBITS(here.bits); + state->lens[state->have++] = here.val; } else { - if (this.val == 16) { - NEEDBITS(this.bits + 2); - DROPBITS(this.bits); + if (here.val == 16) { + NEEDBITS(here.bits + 2); + DROPBITS(here.bits); if (state->have == 0) { strm->msg = (char *)"invalid bit length repeat"; state->mode = BAD; @@ -898,16 +942,16 @@ int flush; copy = 3 + BITS(2); DROPBITS(2); } - else if (this.val == 17) { - NEEDBITS(this.bits + 3); - DROPBITS(this.bits); + else if (here.val == 17) { + NEEDBITS(here.bits + 3); + DROPBITS(here.bits); len = 0; copy = 3 + BITS(3); DROPBITS(3); } else { - NEEDBITS(this.bits + 7); - DROPBITS(this.bits); + NEEDBITS(here.bits + 7); + DROPBITS(here.bits); len = 0; copy = 11 + BITS(7); DROPBITS(7); @@ -925,7 +969,16 @@ int flush; /* handle error breaks in while */ if (state->mode == BAD) break; - /* build code tables */ + /* check for end-of-block code (better have one) */ + if (state->lens[256] == 0) { + strm->msg = (char *)"invalid code -- missing end-of-block"; + state->mode = BAD; + break; + } + + /* build code tables -- note: do not change the lenbits or distbits + values here (9 and 6) without reading the comments in inftrees.h + concerning the ENOUGH constants, which depend on those values */ state->next = state->codes; state->lencode = (code const FAR *)(state->next); state->lenbits = 9; @@ -946,88 +999,102 @@ int flush; break; } Tracev((stderr, "inflate: codes ok\n")); + state->mode = LEN_; + if (flush == Z_TREES) goto inf_leave; + case LEN_: state->mode = LEN; case LEN: if (have >= 6 && left >= 258) { RESTORE(); inflate_fast(strm, out); LOAD(); + if (state->mode == TYPE) + state->back = -1; break; } + state->back = 0; for (;;) { - this = state->lencode[BITS(state->lenbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if (this.op && (this.op & 0xf0) == 0) { - last = this; + if (here.op && (here.op & 0xf0) == 0) { + last = here; for (;;) { - this = state->lencode[last.val + + here = state->lencode[last.val + (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; + if ((unsigned)(last.bits + here.bits) <= bits) break; PULLBYTE(); } DROPBITS(last.bits); + state->back += last.bits; } - DROPBITS(this.bits); - state->length = (unsigned)this.val; - if ((int)(this.op) == 0) { - Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + DROPBITS(here.bits); + state->back += here.bits; + state->length = (unsigned)here.val; + if ((int)(here.op) == 0) { + Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", this.val)); + "inflate: literal 0x%02x\n", here.val)); state->mode = LIT; break; } - if (this.op & 32) { + if (here.op & 32) { Tracevv((stderr, "inflate: end of block\n")); + state->back = -1; state->mode = TYPE; break; } - if (this.op & 64) { + if (here.op & 64) { strm->msg = (char *)"invalid literal/length code"; state->mode = BAD; break; } - state->extra = (unsigned)(this.op) & 15; + state->extra = (unsigned)(here.op) & 15; state->mode = LENEXT; case LENEXT: if (state->extra) { NEEDBITS(state->extra); state->length += BITS(state->extra); DROPBITS(state->extra); + state->back += state->extra; } Tracevv((stderr, "inflate: length %u\n", state->length)); + state->was = state->length; state->mode = DIST; case DIST: for (;;) { - this = state->distcode[BITS(state->distbits)]; - if ((unsigned)(this.bits) <= bits) break; + here = state->distcode[BITS(state->distbits)]; + if ((unsigned)(here.bits) <= bits) break; PULLBYTE(); } - if ((this.op & 0xf0) == 0) { - last = this; + if ((here.op & 0xf0) == 0) { + last = here; for (;;) { - this = state->distcode[last.val + + here = state->distcode[last.val + (BITS(last.bits + last.op) >> last.bits)]; - if ((unsigned)(last.bits + this.bits) <= bits) break; + if ((unsigned)(last.bits + here.bits) <= bits) break; PULLBYTE(); } DROPBITS(last.bits); + state->back += last.bits; } - DROPBITS(this.bits); - if (this.op & 64) { + DROPBITS(here.bits); + state->back += here.bits; + if (here.op & 64) { strm->msg = (char *)"invalid distance code"; state->mode = BAD; break; } - state->offset = (unsigned)this.val; - state->extra = (unsigned)(this.op) & 15; + state->offset = (unsigned)here.val; + state->extra = (unsigned)(here.op) & 15; state->mode = DISTEXT; case DISTEXT: if (state->extra) { NEEDBITS(state->extra); state->offset += BITS(state->extra); DROPBITS(state->extra); + state->back += state->extra; } #ifdef INFLATE_STRICT if (state->offset > state->dmax) { @@ -1036,11 +1103,6 @@ int flush; break; } #endif - if (state->offset > state->whave + out - left) { - strm->msg = (char *)"invalid distance too far back"; - state->mode = BAD; - break; - } Tracevv((stderr, "inflate: distance %u\n", state->offset)); state->mode = MATCH; case MATCH: @@ -1048,12 +1110,32 @@ int flush; copy = out - left; if (state->offset > copy) { /* copy from window */ copy = state->offset - copy; - if (copy > state->write) { - copy -= state->write; + if (copy > state->whave) { + if (state->sane) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR + Trace((stderr, "inflate.c too far\n")); + copy -= state->whave; + if (copy > state->length) copy = state->length; + if (copy > left) copy = left; + left -= copy; + state->length -= copy; + do { + *put++ = 0; + } while (--copy); + if (state->length == 0) state->mode = LEN; + break; +#endif + } + if (copy > state->wnext) { + copy -= state->wnext; from = state->window + (state->wsize - copy); } else - from = state->window + (state->write - copy); + from = state->window + (state->wnext - copy); if (copy > state->length) copy = state->length; } else { /* copy from output */ @@ -1146,7 +1228,8 @@ int flush; strm->adler = state->check = UPDATE(state->check, strm->next_out - out, out); strm->data_type = state->bits + (state->last ? 64 : 0) + - (state->mode == TYPE ? 128 : 0); + (state->mode == TYPE ? 128 : 0) + + (state->mode == LEN_ || state->mode == COPY_ ? 256 : 0); if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) ret = Z_BUF_ERROR; return ret; @@ -1366,3 +1449,32 @@ z_streamp source; dest->state = (struct internal_state FAR *)copy; return Z_OK; } + +int ZEXPORT inflateUndermine(strm, subvert) +z_streamp strm; +int subvert; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + state->sane = !subvert; +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR + return Z_OK; +#else + state->sane = 1; + return Z_DATA_ERROR; +#endif +} + +long ZEXPORT inflateMark(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return -1L << 16; + state = (struct inflate_state FAR *)strm->state; + return ((long)(state->back) << 16) + + (state->mode == COPY ? state->length : + (state->mode == MATCH ? state->was - state->length : 0)); +} |