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Diffstat (limited to 'modules/zlib/src/inflate.c')
| -rw-r--r-- | modules/zlib/src/inflate.c | 1526 |
1 files changed, 1526 insertions, 0 deletions
diff --git a/modules/zlib/src/inflate.c b/modules/zlib/src/inflate.c new file mode 100644 index 0000000000..94ecff015a --- /dev/null +++ b/modules/zlib/src/inflate.c @@ -0,0 +1,1526 @@ +/* inflate.c -- zlib decompression + * Copyright (C) 1995-2022 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +/* + * Change history: + * + * 1.2.beta0 24 Nov 2002 + * - First version -- complete rewrite of inflate to simplify code, avoid + * creation of window when not needed, minimize use of window when it is + * needed, make inffast.c even faster, implement gzip decoding, and to + * improve code readability and style over the previous zlib inflate code + * + * 1.2.beta1 25 Nov 2002 + * - Use pointers for available input and output checking in inffast.c + * - Remove input and output counters in inffast.c + * - Change inffast.c entry and loop from avail_in >= 7 to >= 6 + * - Remove unnecessary second byte pull from length extra in inffast.c + * - Unroll direct copy to three copies per loop in inffast.c + * + * 1.2.beta2 4 Dec 2002 + * - Change external routine names to reduce potential conflicts + * - Correct filename to inffixed.h for fixed tables in inflate.c + * - Make hbuf[] unsigned char to match parameter type in inflate.c + * - Change strm->next_out[-state->offset] to *(strm->next_out - state->offset) + * to avoid negation problem on Alphas (64 bit) in inflate.c + * + * 1.2.beta3 22 Dec 2002 + * - Add comments on state->bits assertion in inffast.c + * - Add comments on op field in inftrees.h + * - Fix bug in reuse of allocated window after inflateReset() + * - Remove bit fields--back to byte structure for speed + * - Remove distance extra == 0 check in inflate_fast()--only helps for lengths + * - Change post-increments to pre-increments in inflate_fast(), PPC biased? + * - Add compile time option, POSTINC, to use post-increments instead (Intel?) + * - Make MATCH copy in inflate() much faster for when inflate_fast() not used + * - Use local copies of stream next and avail values, as well as local bit + * buffer and bit count in inflate()--for speed when inflate_fast() not used + * + * 1.2.beta4 1 Jan 2003 + * - Split ptr - 257 statements in inflate_table() to avoid compiler warnings + * - Move a comment on output buffer sizes from inffast.c to inflate.c + * - Add comments in inffast.c to introduce the inflate_fast() routine + * - 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 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() + * - Added inflateBackInit(), inflateBack(), and inflateBackEnd() in new + * source file infback.c to provide a call-back interface to inflate for + * programs like gzip and unzip -- uses window as output buffer to avoid + * window copying + * + * 1.2.beta5 1 Jan 2003 + * - Improved inflateBack() interface to allow the caller to provide initial + * input in strm. + * - Fixed stored blocks bug in inflateBack() + * + * 1.2.beta6 4 Jan 2003 + * - Added comments in inffast.c on effectiveness of POSTINC + * - Typecasting all around to reduce compiler warnings + * - Changed loops from while (1) or do {} while (1) to for (;;), again to + * make compilers happy + * - Changed type of window in inflateBackInit() to unsigned char * + * + * 1.2.beta7 27 Jan 2003 + * - Changed many types to unsigned or unsigned short to avoid warnings + * - Added inflateCopy() function + * + * 1.2.0 9 Mar 2003 + * - Changed inflateBack() interface to provide separate opaque descriptors + * for the in() and out() functions + * - Changed inflateBack() argument and in_func typedef to swap the length + * and buffer address return values for the input function + * - Check next_in and next_out for Z_NULL on entry to inflate() + * + * The history for versions after 1.2.0 are in ChangeLog in zlib distribution. + */ + +#include "zutil.h" +#include "inftrees.h" +#include "inflate.h" +#include "inffast.h" + +#ifdef MAKEFIXED +# ifndef BUILDFIXED +# define BUILDFIXED +# endif +#endif + +local int inflateStateCheck(z_streamp strm) { + struct inflate_state FAR *state; + if (strm == Z_NULL || + strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) + return 1; + state = (struct inflate_state FAR *)strm->state; + if (state == Z_NULL || state->strm != strm || + state->mode < HEAD || state->mode > SYNC) + return 1; + return 0; +} + +int ZEXPORT inflateResetKeep(z_streamp strm) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + strm->total_in = strm->total_out = state->total = 0; + strm->msg = Z_NULL; + if (state->wrap) /* to support ill-conceived Java test suite */ + strm->adler = state->wrap & 1; + state->mode = HEAD; + state->last = 0; + state->havedict = 0; + state->flags = -1; + state->dmax = 32768U; + state->head = Z_NULL; + 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 inflateReset(z_streamp strm) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + state->wsize = 0; + state->whave = 0; + state->wnext = 0; + return inflateResetKeep(strm); +} + +int ZEXPORT inflateReset2(z_streamp strm, int windowBits) { + int wrap; + struct inflate_state FAR *state; + + /* get the state */ + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + + /* extract wrap request from windowBits parameter */ + if (windowBits < 0) { + if (windowBits < -15) + return Z_STREAM_ERROR; + wrap = 0; + windowBits = -windowBits; + } + else { + wrap = (windowBits >> 4) + 5; +#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_(z_streamp strm, int windowBits, + const char *version, int stream_size) { + int ret; + struct inflate_state FAR *state; + + if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || + stream_size != (int)(sizeof(z_stream))) + return Z_VERSION_ERROR; + if (strm == Z_NULL) return Z_STREAM_ERROR; + strm->msg = Z_NULL; /* in case we return an error */ + if (strm->zalloc == (alloc_func)0) { +#ifdef Z_SOLO + return Z_STREAM_ERROR; +#else + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; +#endif + } + if (strm->zfree == (free_func)0) +#ifdef Z_SOLO + return Z_STREAM_ERROR; +#else + strm->zfree = zcfree; +#endif + state = (struct inflate_state FAR *) + ZALLOC(strm, 1, sizeof(struct inflate_state)); + if (state == Z_NULL) return Z_MEM_ERROR; + Tracev((stderr, "inflate: allocated\n")); + strm->state = (struct internal_state FAR *)state; + state->strm = strm; + state->window = Z_NULL; + state->mode = HEAD; /* to pass state test in inflateReset2() */ + ret = inflateReset2(strm, windowBits); + if (ret != Z_OK) { + ZFREE(strm, state); + strm->state = Z_NULL; + } + return ret; +} + +int ZEXPORT inflateInit_(z_streamp strm, const char *version, + int stream_size) { + return inflateInit2_(strm, DEF_WBITS, version, stream_size); +} + +int ZEXPORT inflatePrime(z_streamp strm, int bits, int value) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + if (bits == 0) + return Z_OK; + state = (struct inflate_state FAR *)strm->state; + if (bits < 0) { + state->hold = 0; + state->bits = 0; + return Z_OK; + } + if (bits > 16 || state->bits + (uInt)bits > 32) return Z_STREAM_ERROR; + value &= (1L << bits) - 1; + state->hold += (unsigned)value << state->bits; + state->bits += (uInt)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. + If BUILDFIXED is defined, then instead this routine builds the tables the + first time it's called, and returns those tables the first time and + thereafter. This reduces the size of the code by about 2K bytes, in + exchange for a little execution time. However, BUILDFIXED should not be + used for threaded applications, since the rewriting of the tables and virgin + may not be thread-safe. + */ +local void fixedtables(struct inflate_state FAR *state) { +#ifdef BUILDFIXED + static int virgin = 1; + static code *lenfix, *distfix; + static code fixed[544]; + + /* build fixed huffman tables if first call (may not be thread safe) */ + if (virgin) { + unsigned sym, bits; + static code *next; + + /* literal/length table */ + sym = 0; + while (sym < 144) state->lens[sym++] = 8; + while (sym < 256) state->lens[sym++] = 9; + while (sym < 280) state->lens[sym++] = 7; + while (sym < 288) state->lens[sym++] = 8; + next = fixed; + lenfix = next; + bits = 9; + inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); + + /* distance table */ + sym = 0; + while (sym < 32) state->lens[sym++] = 5; + distfix = next; + bits = 5; + inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); + + /* do this just once */ + virgin = 0; + } +#else /* !BUILDFIXED */ +# include "inffixed.h" +#endif /* BUILDFIXED */ + state->lencode = lenfix; + state->lenbits = 9; + state->distcode = distfix; + state->distbits = 5; +} + +#ifdef MAKEFIXED +#include <stdio.h> + +/* + Write out the inffixed.h that is #include'd above. Defining MAKEFIXED also + defines BUILDFIXED, so the tables are built on the fly. makefixed() writes + those tables to stdout, which would be piped to inffixed.h. A small program + can simply call makefixed to do this: + + void makefixed(void); + + int main(void) + { + makefixed(); + return 0; + } + + Then that can be linked with zlib built with MAKEFIXED defined and run: + + a.out > inffixed.h + */ +void makefixed(void) +{ + unsigned low, size; + struct inflate_state state; + + fixedtables(&state); + puts(" /* inffixed.h -- table for decoding fixed codes"); + puts(" * Generated automatically by makefixed()."); + puts(" */"); + puts(""); + puts(" /* WARNING: this file should *not* be used by applications."); + puts(" It is part of the implementation of this library and is"); + puts(" subject to change. Applications should only use zlib.h."); + puts(" */"); + puts(""); + size = 1U << 9; + printf(" static const code lenfix[%u] = {", size); + low = 0; + for (;;) { + if ((low % 7) == 0) printf("\n "); + printf("{%u,%u,%d}", (low & 127) == 99 ? 64 : state.lencode[low].op, + state.lencode[low].bits, state.lencode[low].val); + if (++low == size) break; + putchar(','); + } + puts("\n };"); + size = 1U << 5; + printf("\n static const code distfix[%u] = {", size); + low = 0; + for (;;) { + if ((low % 6) == 0) printf("\n "); + printf("{%u,%u,%d}", state.distcode[low].op, state.distcode[low].bits, + state.distcode[low].val); + if (++low == size) break; + putchar(','); + } + puts("\n };"); +} +#endif /* MAKEFIXED */ + +/* + Update the window with the last wsize (normally 32K) bytes written before + returning. If window does not exist yet, create it. This is only called + when a window is already in use, or when output has been written during this + inflate call, but the end of the deflate stream has not been reached yet. + It is also called to create a window for dictionary data when a dictionary + is loaded. + + Providing output buffers larger than 32K to inflate() should provide a speed + advantage, since only the last 32K of output is copied to the sliding window + upon return from inflate(), and since all distances after the first 32K of + output will fall in the output data, making match copies simpler and faster. + The advantage may be dependent on the size of the processor's data caches. + */ +local int updatewindow(z_streamp strm, const Bytef *end, unsigned copy) { + struct inflate_state FAR *state; + unsigned dist; + + state = (struct inflate_state FAR *)strm->state; + + /* if it hasn't been done already, allocate space for the window */ + if (state->window == Z_NULL) { + state->window = (unsigned char FAR *) + ZALLOC(strm, 1U << state->wbits, + sizeof(unsigned char)); + if (state->window == Z_NULL) return 1; + } + + /* if window not in use yet, initialize */ + if (state->wsize == 0) { + state->wsize = 1U << state->wbits; + state->wnext = 0; + state->whave = 0; + } + + /* copy state->wsize or less output bytes into the circular window */ + if (copy >= state->wsize) { + zmemcpy(state->window, end - state->wsize, state->wsize); + state->wnext = 0; + state->whave = state->wsize; + } + else { + dist = state->wsize - state->wnext; + if (dist > copy) dist = copy; + zmemcpy(state->window + state->wnext, end - copy, dist); + copy -= dist; + if (copy) { + zmemcpy(state->window, end - copy, copy); + state->wnext = copy; + state->whave = state->wsize; + } + else { + state->wnext += dist; + if (state->wnext == state->wsize) state->wnext = 0; + if (state->whave < state->wsize) state->whave += dist; + } + } + return 0; +} + +/* Macros for inflate(): */ + +/* check function to use adler32() for zlib or crc32() for gzip */ +#ifdef GUNZIP +# define UPDATE_CHECK(check, buf, len) \ + (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) +#else +# define UPDATE_CHECK(check, buf, len) adler32(check, buf, len) +#endif + +/* check macros for header crc */ +#ifdef GUNZIP +# define CRC2(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + check = crc32(check, hbuf, 2); \ + } while (0) + +# define CRC4(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + hbuf[2] = (unsigned char)((word) >> 16); \ + hbuf[3] = (unsigned char)((word) >> 24); \ + check = crc32(check, hbuf, 4); \ + } while (0) +#endif + +/* Load registers with state in inflate() for speed */ +#define LOAD() \ + do { \ + put = strm->next_out; \ + left = strm->avail_out; \ + next = strm->next_in; \ + have = strm->avail_in; \ + hold = state->hold; \ + bits = state->bits; \ + } while (0) + +/* Restore state from registers in inflate() */ +#define RESTORE() \ + do { \ + strm->next_out = put; \ + strm->avail_out = left; \ + strm->next_in = next; \ + strm->avail_in = have; \ + state->hold = hold; \ + state->bits = bits; \ + } while (0) + +/* Clear the input bit accumulator */ +#define INITBITS() \ + do { \ + hold = 0; \ + bits = 0; \ + } while (0) + +/* Get a byte of input into the bit accumulator, or return from inflate() + if there is no input available. */ +#define PULLBYTE() \ + do { \ + if (have == 0) goto inf_leave; \ + have--; \ + hold += (unsigned long)(*next++) << bits; \ + bits += 8; \ + } while (0) + +/* Assure that there are at least n bits in the bit accumulator. If there is + not enough available input to do that, then return from inflate(). */ +#define NEEDBITS(n) \ + do { \ + while (bits < (unsigned)(n)) \ + PULLBYTE(); \ + } while (0) + +/* Return the low n bits of the bit accumulator (n < 16) */ +#define BITS(n) \ + ((unsigned)hold & ((1U << (n)) - 1)) + +/* Remove n bits from the bit accumulator */ +#define DROPBITS(n) \ + do { \ + hold >>= (n); \ + bits -= (unsigned)(n); \ + } while (0) + +/* Remove zero to seven bits as needed to go to a byte boundary */ +#define BYTEBITS() \ + do { \ + hold >>= bits & 7; \ + bits -= bits & 7; \ + } while (0) + +/* + inflate() uses a state machine to process as much input data and generate as + much output data as possible before returning. The state machine is + structured roughly as follows: + + for (;;) switch (state) { + ... + case STATEn: + if (not enough input data or output space to make progress) + return; + ... make progress ... + state = STATEm; + break; + ... + } + + so when inflate() is called again, the same case is attempted again, and + if the appropriate resources are provided, the machine proceeds to the + next state. The NEEDBITS() macro is usually the way the state evaluates + whether it can proceed or should return. NEEDBITS() does the return if + the requested bits are not available. The typical use of the BITS macros + is: + + NEEDBITS(n); + ... do something with BITS(n) ... + DROPBITS(n); + + where NEEDBITS(n) either returns from inflate() if there isn't enough + input left to load n bits into the accumulator, or it continues. BITS(n) + gives the low n bits in the accumulator. When done, DROPBITS(n) drops + the low n bits off the accumulator. INITBITS() clears the accumulator + and sets the number of available bits to zero. BYTEBITS() discards just + enough bits to put the accumulator on a byte boundary. After BYTEBITS() + and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. + + NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return + if there is no input available. The decoding of variable length codes uses + PULLBYTE() directly in order to pull just enough bytes to decode the next + code, and no more. + + Some states loop until they get enough input, making sure that enough + state information is maintained to continue the loop where it left off + if NEEDBITS() returns in the loop. For example, want, need, and keep + would all have to actually be part of the saved state in case NEEDBITS() + returns: + + case STATEw: + while (want < need) { + NEEDBITS(n); + keep[want++] = BITS(n); + DROPBITS(n); + } + state = STATEx; + case STATEx: + + As shown above, if the next state is also the next case, then the break + is omitted. + + A state may also return if there is not enough output space available to + complete that state. Those states are copying stored data, writing a + literal byte, and copying a matching string. + + When returning, a "goto inf_leave" is used to update the total counters, + update the check value, and determine whether any progress has been made + during that inflate() call in order to return the proper return code. + Progress is defined as a change in either strm->avail_in or strm->avail_out. + When there is a window, goto inf_leave will update the window with the last + output written. If a goto inf_leave occurs in the middle of decompression + and there is no window currently, goto inf_leave will create one and copy + output to the window for the next call of inflate(). + + In this implementation, the flush parameter of inflate() only affects the + return code (per zlib.h). inflate() always writes as much as possible to + strm->next_out, given the space available and the provided input--the effect + documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers + the allocation of and copying into a sliding window until necessary, which + provides the effect documented in zlib.h for Z_FINISH when the entire input + stream available. So the only thing the flush parameter actually does is: + when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it + will return Z_BUF_ERROR if it has not reached the end of the stream. + */ + +int ZEXPORT inflate(z_streamp strm, int flush) { + struct inflate_state FAR *state; + z_const unsigned char FAR *next; /* next input */ + unsigned char FAR *put; /* next output */ + unsigned have, left; /* available input and output */ + unsigned long hold; /* bit buffer */ + unsigned bits; /* bits in bit buffer */ + 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 here; /* current decoding table entry */ + code last; /* parent table entry */ + unsigned len; /* length to copy for repeats, bits to drop */ + int ret; /* return code */ +#ifdef GUNZIP + unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ +#endif + static const unsigned short order[19] = /* permutation of code lengths */ + {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + + if (inflateStateCheck(strm) || strm->next_out == Z_NULL || + (strm->next_in == Z_NULL && strm->avail_in != 0)) + return Z_STREAM_ERROR; + + state = (struct inflate_state FAR *)strm->state; + if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ + LOAD(); + in = have; + out = left; + ret = Z_OK; + for (;;) + switch (state->mode) { + case HEAD: + if (state->wrap == 0) { + state->mode = TYPEDO; + break; + } + NEEDBITS(16); +#ifdef GUNZIP + if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ + if (state->wbits == 0) + state->wbits = 15; + state->check = crc32(0L, Z_NULL, 0); + CRC2(state->check, hold); + INITBITS(); + state->mode = FLAGS; + break; + } + if (state->head != Z_NULL) + state->head->done = -1; + if (!(state->wrap & 1) || /* check if zlib header allowed */ +#else + if ( +#endif + ((BITS(8) << 8) + (hold >> 8)) % 31) { + strm->msg = (char *)"incorrect header check"; + state->mode = BAD; + break; + } + if (BITS(4) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + DROPBITS(4); + len = BITS(4) + 8; + if (state->wbits == 0) + state->wbits = len; + if (len > 15 || len > state->wbits) { + strm->msg = (char *)"invalid window size"; + state->mode = BAD; + break; + } + state->dmax = 1U << len; + state->flags = 0; /* indicate zlib header */ + Tracev((stderr, "inflate: zlib header ok\n")); + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = hold & 0x200 ? DICTID : TYPE; + INITBITS(); + break; +#ifdef GUNZIP + case FLAGS: + NEEDBITS(16); + state->flags = (int)(hold); + if ((state->flags & 0xff) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + if (state->flags & 0xe000) { + strm->msg = (char *)"unknown header flags set"; + state->mode = BAD; + break; + } + if (state->head != Z_NULL) + state->head->text = (int)((hold >> 8) & 1); + if ((state->flags & 0x0200) && (state->wrap & 4)) + CRC2(state->check, hold); + INITBITS(); + state->mode = TIME; + /* fallthrough */ + case TIME: + NEEDBITS(32); + if (state->head != Z_NULL) + state->head->time = hold; + if ((state->flags & 0x0200) && (state->wrap & 4)) + CRC4(state->check, hold); + INITBITS(); + state->mode = OS; + /* fallthrough */ + case OS: + NEEDBITS(16); + if (state->head != Z_NULL) { + state->head->xflags = (int)(hold & 0xff); + state->head->os = (int)(hold >> 8); + } + if ((state->flags & 0x0200) && (state->wrap & 4)) + CRC2(state->check, hold); + INITBITS(); + state->mode = EXLEN; + /* fallthrough */ + case EXLEN: + if (state->flags & 0x0400) { + NEEDBITS(16); + state->length = (unsigned)(hold); + if (state->head != Z_NULL) + state->head->extra_len = (unsigned)hold; + if ((state->flags & 0x0200) && (state->wrap & 4)) + CRC2(state->check, hold); + INITBITS(); + } + else if (state->head != Z_NULL) + state->head->extra = Z_NULL; + state->mode = EXTRA; + /* fallthrough */ + case EXTRA: + if (state->flags & 0x0400) { + copy = state->length; + if (copy > have) copy = have; + if (copy) { + if (state->head != Z_NULL && + state->head->extra != Z_NULL && + (len = state->head->extra_len - state->length) < + state->head->extra_max) { + zmemcpy(state->head->extra + len, next, + len + copy > state->head->extra_max ? + state->head->extra_max - len : copy); + } + if ((state->flags & 0x0200) && (state->wrap & 4)) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + state->length -= copy; + } + if (state->length) goto inf_leave; + } + state->length = 0; + state->mode = NAME; + /* fallthrough */ + case NAME: + if (state->flags & 0x0800) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->name != Z_NULL && + state->length < state->head->name_max) + state->head->name[state->length++] = (Bytef)len; + } while (len && copy < have); + if ((state->flags & 0x0200) && (state->wrap & 4)) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->name = Z_NULL; + state->length = 0; + state->mode = COMMENT; + /* fallthrough */ + case COMMENT: + if (state->flags & 0x1000) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->comment != Z_NULL && + state->length < state->head->comm_max) + state->head->comment[state->length++] = (Bytef)len; + } while (len && copy < have); + if ((state->flags & 0x0200) && (state->wrap & 4)) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->comment = Z_NULL; + state->mode = HCRC; + /* fallthrough */ + case HCRC: + if (state->flags & 0x0200) { + NEEDBITS(16); + if ((state->wrap & 4) && hold != (state->check & 0xffff)) { + strm->msg = (char *)"header crc mismatch"; + state->mode = BAD; + break; + } + INITBITS(); + } + if (state->head != Z_NULL) { + state->head->hcrc = (int)((state->flags >> 9) & 1); + state->head->done = 1; + } + strm->adler = state->check = crc32(0L, Z_NULL, 0); + state->mode = TYPE; + break; +#endif + case DICTID: + NEEDBITS(32); + strm->adler = state->check = ZSWAP32(hold); + INITBITS(); + state->mode = DICT; + /* fallthrough */ + case DICT: + if (state->havedict == 0) { + RESTORE(); + return Z_NEED_DICT; + } + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = TYPE; + /* fallthrough */ + case TYPE: + if (flush == Z_BLOCK || flush == Z_TREES) goto inf_leave; + /* fallthrough */ + case TYPEDO: + if (state->last) { + BYTEBITS(); + state->mode = CHECK; + break; + } + NEEDBITS(3); + state->last = BITS(1); + DROPBITS(1); + switch (BITS(2)) { + case 0: /* stored block */ + Tracev((stderr, "inflate: stored block%s\n", + state->last ? " (last)" : "")); + state->mode = STORED; + break; + case 1: /* fixed block */ + fixedtables(state); + Tracev((stderr, "inflate: fixed codes block%s\n", + state->last ? " (last)" : "")); + 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", + state->last ? " (last)" : "")); + state->mode = TABLE; + break; + case 3: + strm->msg = (char *)"invalid block type"; + state->mode = BAD; + } + DROPBITS(2); + break; + case STORED: + BYTEBITS(); /* go to byte boundary */ + NEEDBITS(32); + if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { + strm->msg = (char *)"invalid stored block lengths"; + state->mode = BAD; + break; + } + state->length = (unsigned)hold & 0xffff; + Tracev((stderr, "inflate: stored length %u\n", + state->length)); + INITBITS(); + state->mode = COPY_; + if (flush == Z_TREES) goto inf_leave; + /* fallthrough */ + case COPY_: + state->mode = COPY; + /* fallthrough */ + case COPY: + copy = state->length; + if (copy) { + if (copy > have) copy = have; + if (copy > left) copy = left; + if (copy == 0) goto inf_leave; + zmemcpy(put, next, copy); + have -= copy; + next += copy; + left -= copy; + put += copy; + state->length -= copy; + break; + } + Tracev((stderr, "inflate: stored end\n")); + state->mode = TYPE; + break; + case TABLE: + NEEDBITS(14); + state->nlen = BITS(5) + 257; + DROPBITS(5); + state->ndist = BITS(5) + 1; + DROPBITS(5); + state->ncode = BITS(4) + 4; + DROPBITS(4); +#ifndef PKZIP_BUG_WORKAROUND + if (state->nlen > 286 || state->ndist > 30) { + strm->msg = (char *)"too many length or distance symbols"; + state->mode = BAD; + break; + } +#endif + Tracev((stderr, "inflate: table sizes ok\n")); + state->have = 0; + state->mode = LENLENS; + /* fallthrough */ + case LENLENS: + while (state->have < state->ncode) { + NEEDBITS(3); + state->lens[order[state->have++]] = (unsigned short)BITS(3); + DROPBITS(3); + } + while (state->have < 19) + state->lens[order[state->have++]] = 0; + state->next = state->codes; + state->lencode = (const code FAR *)(state->next); + state->lenbits = 7; + ret = inflate_table(CODES, state->lens, 19, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid code lengths set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: code lengths ok\n")); + state->have = 0; + state->mode = CODELENS; + /* fallthrough */ + case CODELENS: + while (state->have < state->nlen + state->ndist) { + for (;;) { + here = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(here.bits) <= bits) break; + PULLBYTE(); + } + if (here.val < 16) { + DROPBITS(here.bits); + state->lens[state->have++] = here.val; + } + else { + 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; + break; + } + len = state->lens[state->have - 1]; + copy = 3 + BITS(2); + DROPBITS(2); + } + else if (here.val == 17) { + NEEDBITS(here.bits + 3); + DROPBITS(here.bits); + len = 0; + copy = 3 + BITS(3); + DROPBITS(3); + } + else { + NEEDBITS(here.bits + 7); + DROPBITS(here.bits); + len = 0; + copy = 11 + BITS(7); + DROPBITS(7); + } + if (state->have + copy > state->nlen + state->ndist) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + while (copy--) + state->lens[state->have++] = (unsigned short)len; + } + } + + /* handle error breaks in while */ + if (state->mode == BAD) break; + + /* 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 = (const code FAR *)(state->next); + state->lenbits = 9; + ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid literal/lengths set"; + state->mode = BAD; + break; + } + state->distcode = (const code FAR *)(state->next); + state->distbits = 6; + ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, + &(state->next), &(state->distbits), state->work); + if (ret) { + strm->msg = (char *)"invalid distances set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: codes ok\n")); + state->mode = LEN_; + if (flush == Z_TREES) goto inf_leave; + /* fallthrough */ + case LEN_: + state->mode = LEN; + /* fallthrough */ + 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 (;;) { + here = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(here.bits) <= bits) break; + PULLBYTE(); + } + if (here.op && (here.op & 0xf0) == 0) { + last = here; + for (;;) { + here = state->lencode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + here.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + state->back += last.bits; + } + 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", here.val)); + state->mode = LIT; + break; + } + if (here.op & 32) { + Tracevv((stderr, "inflate: end of block\n")); + state->back = -1; + state->mode = TYPE; + break; + } + if (here.op & 64) { + strm->msg = (char *)"invalid literal/length code"; + state->mode = BAD; + break; + } + state->extra = (unsigned)(here.op) & 15; + state->mode = LENEXT; + /* fallthrough */ + 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; + /* fallthrough */ + case DIST: + for (;;) { + here = state->distcode[BITS(state->distbits)]; + if ((unsigned)(here.bits) <= bits) break; + PULLBYTE(); + } + if ((here.op & 0xf0) == 0) { + last = here; + for (;;) { + here = state->distcode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + here.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + state->back += last.bits; + } + DROPBITS(here.bits); + state->back += here.bits; + if (here.op & 64) { + strm->msg = (char *)"invalid distance code"; + state->mode = BAD; + break; + } + state->offset = (unsigned)here.val; + state->extra = (unsigned)(here.op) & 15; + state->mode = DISTEXT; + /* fallthrough */ + 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) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#endif + Tracevv((stderr, "inflate: distance %u\n", state->offset)); + state->mode = MATCH; + /* fallthrough */ + case MATCH: + if (left == 0) goto inf_leave; + copy = out - left; + if (state->offset > copy) { /* copy from window */ + copy = state->offset - copy; + 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->wnext - copy); + if (copy > state->length) copy = state->length; + } + else { /* copy from output */ + from = put - state->offset; + copy = state->length; + } + if (copy > left) copy = left; + left -= copy; + state->length -= copy; + do { + *put++ = *from++; + } while (--copy); + if (state->length == 0) state->mode = LEN; + break; + case LIT: + if (left == 0) goto inf_leave; + *put++ = (unsigned char)(state->length); + left--; + state->mode = LEN; + break; + case CHECK: + if (state->wrap) { + NEEDBITS(32); + out -= left; + strm->total_out += out; + state->total += out; + if ((state->wrap & 4) && out) + strm->adler = state->check = + UPDATE_CHECK(state->check, put - out, out); + out = left; + if ((state->wrap & 4) && ( +#ifdef GUNZIP + state->flags ? hold : +#endif + ZSWAP32(hold)) != state->check) { + strm->msg = (char *)"incorrect data check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: check matches trailer\n")); + } +#ifdef GUNZIP + state->mode = LENGTH; + /* fallthrough */ + case LENGTH: + if (state->wrap && state->flags) { + NEEDBITS(32); + if ((state->wrap & 4) && hold != (state->total & 0xffffffff)) { + strm->msg = (char *)"incorrect length check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: length matches trailer\n")); + } +#endif + state->mode = DONE; + /* fallthrough */ + case DONE: + ret = Z_STREAM_END; + goto inf_leave; + case BAD: + ret = Z_DATA_ERROR; + goto inf_leave; + case MEM: + return Z_MEM_ERROR; + case SYNC: + /* fallthrough */ + default: + return Z_STREAM_ERROR; + } + + /* + Return from inflate(), updating the total counts and the check value. + If there was no progress during the inflate() call, return a buffer + error. Call updatewindow() to create and/or update the window state. + Note: a memory error from inflate() is non-recoverable. + */ + inf_leave: + RESTORE(); + if (state->wsize || (out != strm->avail_out && state->mode < BAD && + (state->mode < CHECK || flush != Z_FINISH))) + if (updatewindow(strm, strm->next_out, out - strm->avail_out)) { + state->mode = MEM; + return Z_MEM_ERROR; + } + in -= strm->avail_in; + out -= strm->avail_out; + strm->total_in += in; + strm->total_out += out; + state->total += out; + if ((state->wrap & 4) && out) + strm->adler = state->check = + UPDATE_CHECK(state->check, strm->next_out - out, out); + strm->data_type = (int)state->bits + (state->last ? 64 : 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; +} + +int ZEXPORT inflateEnd(z_streamp strm) { + struct inflate_state FAR *state; + if (inflateStateCheck(strm)) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (state->window != Z_NULL) ZFREE(strm, state->window); + ZFREE(strm, strm->state); + strm->state = Z_NULL; + Tracev((stderr, "inflate: end\n")); + return Z_OK; +} + +int ZEXPORT inflateGetDictionary(z_streamp strm, Bytef *dictionary, + uInt *dictLength) { + struct inflate_state FAR *state; + + /* check state */ + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + + /* copy dictionary */ + if (state->whave && dictionary != Z_NULL) { + zmemcpy(dictionary, state->window + state->wnext, + state->whave - state->wnext); + zmemcpy(dictionary + state->whave - state->wnext, + state->window, state->wnext); + } + if (dictLength != Z_NULL) + *dictLength = state->whave; + return Z_OK; +} + +int ZEXPORT inflateSetDictionary(z_streamp strm, const Bytef *dictionary, + uInt dictLength) { + struct inflate_state FAR *state; + unsigned long dictid; + int ret; + + /* check state */ + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (state->wrap != 0 && state->mode != DICT) + return Z_STREAM_ERROR; + + /* check for correct dictionary identifier */ + if (state->mode == DICT) { + dictid = adler32(0L, Z_NULL, 0); + dictid = adler32(dictid, dictionary, dictLength); + if (dictid != state->check) + return Z_DATA_ERROR; + } + + /* copy dictionary to window using updatewindow(), which will amend the + existing dictionary if appropriate */ + ret = updatewindow(strm, dictionary + dictLength, dictLength); + if (ret) { + state->mode = MEM; + return Z_MEM_ERROR; + } + state->havedict = 1; + Tracev((stderr, "inflate: dictionary set\n")); + return Z_OK; +} + +int ZEXPORT inflateGetHeader(z_streamp strm, gz_headerp head) { + struct inflate_state FAR *state; + + /* check state */ + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if ((state->wrap & 2) == 0) return Z_STREAM_ERROR; + + /* save header structure */ + state->head = head; + head->done = 0; + return Z_OK; +} + +/* + Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found + or when out of input. When called, *have is the number of pattern bytes + found in order so far, in 0..3. On return *have is updated to the new + state. If on return *have equals four, then the pattern was found and the + return value is how many bytes were read including the last byte of the + pattern. If *have is less than four, then the pattern has not been found + yet and the return value is len. In the latter case, syncsearch() can be + called again with more data and the *have state. *have is initialized to + zero for the first call. + */ +local unsigned syncsearch(unsigned FAR *have, const unsigned char FAR *buf, + unsigned len) { + unsigned got; + unsigned next; + + got = *have; + next = 0; + while (next < len && got < 4) { + if ((int)(buf[next]) == (got < 2 ? 0 : 0xff)) + got++; + else if (buf[next]) + got = 0; + else + got = 4 - got; + next++; + } + *have = got; + return next; +} + +int ZEXPORT inflateSync(z_streamp strm) { + unsigned len; /* number of bytes to look at or looked at */ + int flags; /* temporary to save header status */ + unsigned long in, out; /* temporary to save total_in and total_out */ + unsigned char buf[4]; /* to restore bit buffer to byte string */ + struct inflate_state FAR *state; + + /* check parameters */ + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR; + + /* if first time, start search in bit buffer */ + if (state->mode != SYNC) { + state->mode = SYNC; + state->hold >>= state->bits & 7; + state->bits -= state->bits & 7; + len = 0; + while (state->bits >= 8) { + buf[len++] = (unsigned char)(state->hold); + state->hold >>= 8; + state->bits -= 8; + } + state->have = 0; + syncsearch(&(state->have), buf, len); + } + + /* search available input */ + len = syncsearch(&(state->have), strm->next_in, strm->avail_in); + strm->avail_in -= len; + strm->next_in += len; + strm->total_in += len; + + /* return no joy or set up to restart inflate() on a new block */ + if (state->have != 4) return Z_DATA_ERROR; + if (state->flags == -1) + state->wrap = 0; /* if no header yet, treat as raw */ + else + state->wrap &= ~4; /* no point in computing a check value now */ + flags = state->flags; + in = strm->total_in; out = strm->total_out; + inflateReset(strm); + strm->total_in = in; strm->total_out = out; + state->flags = flags; + state->mode = TYPE; + return Z_OK; +} + +/* + Returns true if inflate is currently at the end of a block generated by + Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP + implementation to provide an additional safety check. PPP uses + Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored + block. When decompressing, PPP checks that at the end of input packet, + inflate is waiting for these length bytes. + */ +int ZEXPORT inflateSyncPoint(z_streamp strm) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + return state->mode == STORED && state->bits == 0; +} + +int ZEXPORT inflateCopy(z_streamp dest, z_streamp source) { + struct inflate_state FAR *state; + struct inflate_state FAR *copy; + unsigned char FAR *window; + unsigned wsize; + + /* check input */ + if (inflateStateCheck(source) || dest == Z_NULL) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)source->state; + + /* allocate space */ + copy = (struct inflate_state FAR *) + ZALLOC(source, 1, sizeof(struct inflate_state)); + if (copy == Z_NULL) return Z_MEM_ERROR; + window = Z_NULL; + if (state->window != Z_NULL) { + window = (unsigned char FAR *) + ZALLOC(source, 1U << state->wbits, sizeof(unsigned char)); + if (window == Z_NULL) { + ZFREE(source, copy); + return Z_MEM_ERROR; + } + } + + /* copy state */ + zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream)); + zmemcpy((voidpf)copy, (voidpf)state, sizeof(struct inflate_state)); + copy->strm = dest; + if (state->lencode >= state->codes && + state->lencode <= state->codes + ENOUGH - 1) { + copy->lencode = copy->codes + (state->lencode - state->codes); + copy->distcode = copy->codes + (state->distcode - state->codes); + } + copy->next = copy->codes + (state->next - state->codes); + if (window != Z_NULL) { + wsize = 1U << state->wbits; + zmemcpy(window, state->window, wsize); + } + copy->window = window; + dest->state = (struct internal_state FAR *)copy; + return Z_OK; +} + +int ZEXPORT inflateUndermine(z_streamp strm, int subvert) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; +#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR + state->sane = !subvert; + return Z_OK; +#else + (void)subvert; + state->sane = 1; + return Z_DATA_ERROR; +#endif +} + +int ZEXPORT inflateValidate(z_streamp strm, int check) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (check && state->wrap) + state->wrap |= 4; + else + state->wrap &= ~4; + return Z_OK; +} + +long ZEXPORT inflateMark(z_streamp strm) { + struct inflate_state FAR *state; + + if (inflateStateCheck(strm)) + return -(1L << 16); + state = (struct inflate_state FAR *)strm->state; + return (long)(((unsigned long)((long)state->back)) << 16) + + (state->mode == COPY ? state->length : + (state->mode == MATCH ? state->was - state->length : 0)); +} + +unsigned long ZEXPORT inflateCodesUsed(z_streamp strm) { + struct inflate_state FAR *state; + if (inflateStateCheck(strm)) return (unsigned long)-1; + state = (struct inflate_state FAR *)strm->state; + return (unsigned long)(state->next - state->codes); +} |