/* funzip.c -- Not copyrighted 1992 by Mark Adler */ #define VERSION "1.3p1 of 10 January 1993" /* You can do whatever you like with this source file, though I would prefer that if you modify it and redistribute it that you include comments to that effect with your name and the date. Thank you. History: vers date who what ---- --------- -------------- ------------------------------------ 1.0 13 Aug 92 M. Adler really simple unzip filter. 1.1 13 Aug 92 M. Adler cleaned up somewhat, give help if stdin not redirected, warn if more zip file entries after the first. 1.2 15 Aug 92 M. Adler added check of lengths for stored entries, added more help. 1.3 16 Aug 92 M. Adler removed redundant #define's, added decryption. 1.3p1 10 Jan 93 G. Roelofs incorporated fixes from 2.2 beta: [1.4] G. Roelofs added exit(0). [1.5] K. U. Rommel changed read/write modes for OS/2. [1.7] G. Roelofs changed to use DOS_OS2. [1.8] M. Adler improved inflation error msgs. [1.9] G. Roelofs changed ULONG/UWORD/byte to ulg/ush/uch; renamed inflate_entry() to inflate(). [2.1] J. Gailly fixed crypt/store bug, G. Roelofs fixed decryption check (single byte). */ /* All funzip does is take a zip file from stdin and decompress the first entry to stdout. The entry has to be either deflated or stored. If the entry is encrypted, then the decryption password must be supplied on the command line as the first argument. funzip needs to be linked with inflate.o compiled from the unzip source. If decryption is desired, then it needs to be compiled with -DCRYPT and linked also with crypt.o. */ #include "unzip.h" /* enforce binary i/o if recognized */ #if defined(__STDC__) || defined(DOS_OS2) # define BINIO #endif #ifdef BINIO # define FOPR "rb" # define FOPW "wb" #else # define FOPR "r" # define FOPW "w" #endif /* PKZIP header definitions */ #define LOCSIG 0x04034b50L /* four byte lead-in (lsb first) */ #define LOCFLG 6 /* offset of bit flag */ #define CRPFLG 1 /* bit for encrypted entry */ #define EXTFLG 8 /* bit for extended local header */ #define LOCHOW 8 /* offset of compression method */ #define LOCTIM 10 /* file mod time (for decryption) */ #define LOCCRC 14 /* offset of crc */ #define LOCSIZ 18 /* offset of compressed size */ #define LOCLEN 22 /* offset of uncompressed length */ #define LOCFIL 26 /* offset of file name field length */ #define LOCEXT 28 /* offset of extra field length */ #define LOCHDR 30 /* size of local header, including sig */ #define EXTHDR 16 /* size of extended local header, inc sig */ #define RAND_HEAD_LEN 12 /* length of encryption header */ /* Macros for getting two byte and four byte header values */ #define SH(p) ((UWORD)(byte)((p)[0]) | ((UWORD)(byte)((p)[1]) << 8)) #define LG(p) ((ULONG)(SH(p)) | ((ULONG)(SH((p)+2)) << 16)) /* Function prototypes */ ULONG updcrc OF((byte *, int)); int inflate OF((void)); void err OF((int, char *)); void main OF((int, char **)); /* Globals */ FILE *in, *out; /* input and output files */ union work area; /* inflate sliding window */ byte *outbuf; /* malloc'ed output buffer */ byte *outptr; /* points to next byte in output buffer */ int outcnt; /* bytes in output buffer */ ULONG outsiz; /* total bytes written to out */ int decrypt; /* flag to turn on decryption */ char *key; /* not used--needed to link crypt.c */ /* Masks for inflate.c */ UWORD mask_bits[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff }; /* Table of CRC-32's of all single byte values (made by makecrc.c) */ ULONG crc_32_tab[] = { 0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L, 0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L, 0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L, 0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL, 0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L, 0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L, 0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L, 0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL, 0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L, 0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL, 0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L, 0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L, 0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L, 0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL, 0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL, 0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L, 0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL, 0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L, 0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L, 0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L, 0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL, 0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L, 0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L, 0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL, 0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L, 0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L, 0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L, 0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L, 0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L, 0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL, 0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL, 0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L, 0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L, 0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL, 0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL, 0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L, 0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL, 0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L, 0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL, 0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L, 0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL, 0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L, 0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L, 0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL, 0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L, 0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L, 0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L, 0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L, 0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L, 0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L, 0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL, 0x2d02ef8dL }; ULONG updcrc(s, n) byte *s; /* pointer to bytes to pump through */ int n; /* number of bytes in s[] */ /* Run a set of bytes through the crc shift register. If s is a NULL pointer, then initialize the crc shift register contents instead. Return the current crc in either case. */ { register ULONG c; /* temporary variable */ static ULONG crc = 0xffffffffL; /* shift register contents */ if (s == NULL) c = 0xffffffffL; else { c = crc; while (n--) c = crc_32_tab[((int)c ^ (*s++)) & 0xff] ^ (c >> 8); } crc = c; return c ^ 0xffffffffL; /* (instead of ~c for 64-bit machines) */ } void err(n, m) int n; char *m; /* Exit on error with a message and a code */ { fprintf(stderr, "funzip error: %s\n", m); exit(n); } int ReadByte(b) UWORD *b; /* Used by inflate.c to get a byte (archaism from unzip) */ { register int c = getc(in); if (c == EOF) return 0; #ifdef CRYPT if (decrypt) update_keys(c ^= decrypt_byte()); #endif /* CRYPT */ *b = (UWORD)c; return 8; } int FlushOutput() /* Empty output buffer */ { if (outcnt) { updcrc(outbuf, outcnt); if (fwrite((char *)outbuf, 1,outcnt,out) != outcnt) err(9, "out of space on stdout"); outsiz += outcnt; outptr = outbuf; outcnt = 0; } return 0; } void main(argc, argv) int argc; char **argv; /* Given a zip file on stdin, decompress the first entry to stdout. */ { byte h[LOCHDR]; /* first local header */ /* if stdin not redirected, give the user help */ if (isatty(0)) { fprintf(stderr, "FUnZip (Filter UnZip), version %s\n%s", VERSION, #ifdef CRYPT "usage: funzip [password] < infile.zip > outfile\n"); #else /* !CRYPT */ "usage: funzip < infile.zip > outfile\n"); #endif /* ?CRYPT */ fprintf(stderr, " extracts to stdout the first zip entry of stdin.\n"); exit(3); } /* prepare to be a binary filter */ if ((outbuf = (byte *)malloc(OUTBUFSIZ)) == NULL) err(1, "out of memory"); #ifdef DOS_OS2 setmode(0, O_BINARY); /* some buggy C libraries require BOTH :-( the */ #endif /* setmode() call AND the fdopen() in binary mode */ if ((in = fdopen(0, FOPR)) == NULL) err(2, "cannot find stdin"); #ifdef DOS_OS2 setmode(1, O_BINARY); #endif if ((out = fdopen(1, FOPW)) == NULL) err(2, "cannot write to stdout"); /* read local header, check validity, and skip name and extra fields */ if (fread((char *)h, 1, LOCHDR, in) != LOCHDR || LG(h) != LOCSIG) err(3, "input not a zip file or empty"); if (SH(h + LOCHOW) != STORED && SH(h + LOCHOW) != DEFLATED) err(3, "first entry not deflated or stored--can't funzip"); fseek(in, (long)(SH(h + LOCFIL)) + (long)(SH(h + LOCEXT)), 1); /* if entry encrypted, decrypt and validate encryption header */ if ((decrypt = h[LOCFLG] & CRPFLG) != 0) #ifdef CRYPT { UWORD i, e; if (argc < 2) err(3, "need password on command line for encrypted entry"); init_keys(argv[1]); for (i = 0; i < RAND_HEAD_LEN; i++) ReadByte(&e); if (e != (ush)(h[LOCFLG] & EXTFLG ? h[LOCTIM + 1] : h[LOCCRC + 3])) err(3, "incorrect password for first entry"); } #else /* !CRYPT */ err(3, "cannot decrypt entry (need to recompile funzip with crypt.c)"); #endif /* ?CRYPT */ /* prepare output buffer and crc */ outptr = outbuf; outcnt = 0; outsiz = 0L; updcrc(NULL, 0); /* decompress */ if (h[LOCHOW]) { /* deflated entry */ int r; if ((r = inflate()) != 0) if (r == 3) err(1, "out of memory"); else err(4, "invalid compressed data--format violated"); } else { /* stored entry */ register ULONG n; n = LG(h + LOCLEN); if (n != LG(h + LOCSIZ) - (decrypt ? RAND_HEAD_LEN : 0)) { fprintf(stderr, "len %ld, siz %ld\n", n, LG(h + LOCSIZ)); err(4, "invalid compressed data--length mismatch"); } while (n--) { ush c = getc(in); #ifdef CRYPT if (decrypt) update_keys(c ^= decrypt_byte()); #endif OUTB(c); } } FlushOutput(); fflush(out); /* if extended header, get it */ if ((h[LOCFLG] & EXTFLG) && fread((char *)h + LOCCRC - 4, 1, EXTHDR, in) != EXTHDR) err(3, "zip file ended prematurely"); /* validate decompression */ if (LG(h + LOCCRC) != updcrc(outbuf, 0)) err(4, "invalid compressed data--crc error"); if (LG(h + LOCLEN) != outsiz) err(4, "invalid compressed data--length error"); /* check if there are more entries */ if (fread((char *)h, 1, 4, in) == 4 && LG(h) == LOCSIG) fprintf(stderr, "funzip warning: zip file has more than one entry--rest ignored\n"); exit(0); }