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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /gnu/usr.bin/gzip/unzip.c
initial import of NetBSD tree
Diffstat (limited to 'gnu/usr.bin/gzip/unzip.c')
-rw-r--r--gnu/usr.bin/gzip/unzip.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/gnu/usr.bin/gzip/unzip.c b/gnu/usr.bin/gzip/unzip.c
new file mode 100644
index 00000000000..bd13acf789c
--- /dev/null
+++ b/gnu/usr.bin/gzip/unzip.c
@@ -0,0 +1,199 @@
+/* unzip.c -- decompress files in gzip or pkzip format.
+ * Copyright (C) 1992-1993 Jean-loup Gailly
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License, see the file COPYING.
+ *
+ * The code in this file is derived from the file funzip.c written
+ * and put in the public domain by Mark Adler.
+ */
+
+/*
+ This version can extract files in gzip or pkzip format.
+ For the latter, only the first entry is extracted, and it has to be
+ either deflated or stored.
+ */
+
+#ifdef RCSID
+static char rcsid[] = "$Id: unzip.c,v 1.1 1995/10/18 08:40:54 deraadt Exp $";
+#endif
+
+#include "tailor.h"
+#include "gzip.h"
+#include "crypt.h"
+
+/* 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 */
+
+
+/* Globals */
+
+int decrypt; /* flag to turn on decryption */
+char *key; /* not used--needed to link crypt.c */
+int pkzip = 0; /* set for a pkzip file */
+int ext_header = 0; /* set if extended local header */
+
+/* ===========================================================================
+ * Check zip file and advance inptr to the start of the compressed data.
+ * Get ofname from the local header if necessary.
+ */
+int check_zipfile(in)
+ int in; /* input file descriptors */
+{
+ uch *h = inbuf + inptr; /* first local header */
+
+ ifd = in;
+
+ /* Check validity of local header, and skip name and extra fields */
+ inptr += LOCHDR + SH(h + LOCFIL) + SH(h + LOCEXT);
+
+ if (inptr > insize || LG(h) != LOCSIG) {
+ fprintf(stderr, "\n%s: %s: not a valid zip file\n",
+ progname, ifname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+ method = h[LOCHOW];
+ if (method != STORED && method != DEFLATED) {
+ fprintf(stderr,
+ "\n%s: %s: first entry not deflated or stored -- use unzip\n",
+ progname, ifname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+
+ /* If entry encrypted, decrypt and validate encryption header */
+ if ((decrypt = h[LOCFLG] & CRPFLG) != 0) {
+ fprintf(stderr, "\n%s: %s: encrypted file -- use unzip\n",
+ progname, ifname);
+ exit_code = ERROR;
+ return ERROR;
+ }
+
+ /* Save flags for unzip() */
+ ext_header = (h[LOCFLG] & EXTFLG) != 0;
+ pkzip = 1;
+
+ /* Get ofname and time stamp from local header (to be done) */
+ return OK;
+}
+
+/* ===========================================================================
+ * Unzip in to out. This routine works on both gzip and pkzip files.
+ *
+ * IN assertions: the buffer inbuf contains already the beginning of
+ * the compressed data, from offsets inptr to insize-1 included.
+ * The magic header has already been checked. The output buffer is cleared.
+ */
+int unzip(in, out)
+ int in, out; /* input and output file descriptors */
+{
+ ulg orig_crc = 0; /* original crc */
+ ulg orig_len = 0; /* original uncompressed length */
+ int n;
+ uch buf[EXTHDR]; /* extended local header */
+
+ ifd = in;
+ ofd = out;
+
+ updcrc(NULL, 0); /* initialize crc */
+
+ if (pkzip && !ext_header) { /* crc and length at the end otherwise */
+ orig_crc = LG(inbuf + LOCCRC);
+ orig_len = LG(inbuf + LOCLEN);
+ }
+
+ /* Decompress */
+ if (method == DEFLATED) {
+
+ int res = inflate();
+
+ if (res == 3) {
+ error("out of memory");
+ } else if (res != 0) {
+ error("invalid compressed data--format violated");
+ }
+
+ } else if (pkzip && method == STORED) {
+
+ register ulg n = LG(inbuf + LOCLEN);
+
+ if (n != LG(inbuf + LOCSIZ) - (decrypt ? RAND_HEAD_LEN : 0)) {
+
+ fprintf(stderr, "len %ld, siz %ld\n", n, LG(inbuf + LOCSIZ));
+ error("invalid compressed data--length mismatch");
+ }
+ while (n--) {
+ uch c = (uch)get_byte();
+#ifdef CRYPT
+ if (decrypt) zdecode(c);
+#endif
+ put_ubyte(c);
+ }
+ flush_window();
+ } else {
+ error("internal error, invalid method");
+ }
+
+ /* Get the crc and original length */
+ if (!pkzip) {
+ /* crc32 (see algorithm.doc)
+ * uncompressed input size modulo 2^32
+ */
+ for (n = 0; n < 8; n++) {
+ buf[n] = (uch)get_byte(); /* may cause an error if EOF */
+ }
+ orig_crc = LG(buf);
+ orig_len = LG(buf+4);
+
+ } else if (ext_header) { /* If extended header, check it */
+ /* signature - 4bytes: 0x50 0x4b 0x07 0x08
+ * CRC-32 value
+ * compressed size 4-bytes
+ * uncompressed size 4-bytes
+ */
+ for (n = 0; n < EXTHDR; n++) {
+ buf[n] = (uch)get_byte(); /* may cause an error if EOF */
+ }
+ orig_crc = LG(buf+4);
+ orig_len = LG(buf+12);
+ }
+
+ /* Validate decompression */
+ if (orig_crc != updcrc(outbuf, 0)) {
+ error("invalid compressed data--crc error");
+ }
+ if (orig_len != (ulg)bytes_out) {
+ error("invalid compressed data--length error");
+ }
+
+ /* Check if there are more entries in a pkzip file */
+ if (pkzip && inptr + 4 < insize && LG(inbuf+inptr) == LOCSIG) {
+ if (to_stdout) {
+ WARN((stderr,
+ "%s: %s has more than one entry--rest ignored\n",
+ progname, ifname));
+ } else {
+ /* Don't destroy the input zip file */
+ fprintf(stderr,
+ "%s: %s has more than one entry -- unchanged\n",
+ progname, ifname);
+ exit_code = ERROR;
+ ext_header = pkzip = 0;
+ return ERROR;
+ }
+ }
+ ext_header = pkzip = 0; /* for next file */
+ return OK;
+}