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-rw-r--r--lib/zlib_inflate/inflate.c248
1 files changed, 248 insertions, 0 deletions
diff --git a/lib/zlib_inflate/inflate.c b/lib/zlib_inflate/inflate.c
new file mode 100644
index 000000000000..3d94cb90c1d3
--- /dev/null
+++ b/lib/zlib_inflate/inflate.c
@@ -0,0 +1,248 @@
+/* inflate.c -- zlib interface to inflate modules
+ * Copyright (C) 1995-1998 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include <linux/module.h>
+#include <linux/zutil.h>
+#include "infblock.h"
+#include "infutil.h"
+
+int zlib_inflate_workspacesize(void)
+{
+ return sizeof(struct inflate_workspace);
+}
+
+
+int zlib_inflateReset(
+ z_streamp z
+)
+{
+ if (z == NULL || z->state == NULL || z->workspace == NULL)
+ return Z_STREAM_ERROR;
+ z->total_in = z->total_out = 0;
+ z->msg = NULL;
+ z->state->mode = z->state->nowrap ? BLOCKS : METHOD;
+ zlib_inflate_blocks_reset(z->state->blocks, z, NULL);
+ return Z_OK;
+}
+
+
+int zlib_inflateEnd(
+ z_streamp z
+)
+{
+ if (z == NULL || z->state == NULL || z->workspace == NULL)
+ return Z_STREAM_ERROR;
+ if (z->state->blocks != NULL)
+ zlib_inflate_blocks_free(z->state->blocks, z);
+ z->state = NULL;
+ return Z_OK;
+}
+
+
+int zlib_inflateInit2_(
+ z_streamp z,
+ int w,
+ const char *version,
+ int stream_size
+)
+{
+ if (version == NULL || version[0] != ZLIB_VERSION[0] ||
+ stream_size != sizeof(z_stream) || z->workspace == NULL)
+ return Z_VERSION_ERROR;
+
+ /* initialize state */
+ z->msg = NULL;
+ z->state = &WS(z)->internal_state;
+ z->state->blocks = NULL;
+
+ /* handle undocumented nowrap option (no zlib header or check) */
+ z->state->nowrap = 0;
+ if (w < 0)
+ {
+ w = - w;
+ z->state->nowrap = 1;
+ }
+
+ /* set window size */
+ if (w < 8 || w > 15)
+ {
+ zlib_inflateEnd(z);
+ return Z_STREAM_ERROR;
+ }
+ z->state->wbits = (uInt)w;
+
+ /* create inflate_blocks state */
+ if ((z->state->blocks =
+ zlib_inflate_blocks_new(z, z->state->nowrap ? NULL : zlib_adler32, (uInt)1 << w))
+ == NULL)
+ {
+ zlib_inflateEnd(z);
+ return Z_MEM_ERROR;
+ }
+
+ /* reset state */
+ zlib_inflateReset(z);
+ return Z_OK;
+}
+
+
+/*
+ * At the end of a Deflate-compressed PPP packet, we expect to have seen
+ * a `stored' block type value but not the (zero) length bytes.
+ */
+static int zlib_inflate_packet_flush(inflate_blocks_statef *s)
+{
+ if (s->mode != LENS)
+ return Z_DATA_ERROR;
+ s->mode = TYPE;
+ return Z_OK;
+}
+
+
+int zlib_inflateInit_(
+ z_streamp z,
+ const char *version,
+ int stream_size
+)
+{
+ return zlib_inflateInit2_(z, DEF_WBITS, version, stream_size);
+}
+
+#undef NEEDBYTE
+#undef NEXTBYTE
+#define NEEDBYTE {if(z->avail_in==0)goto empty;r=trv;}
+#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++)
+
+int zlib_inflate(
+ z_streamp z,
+ int f
+)
+{
+ int r, trv;
+ uInt b;
+
+ if (z == NULL || z->state == NULL || z->next_in == NULL)
+ return Z_STREAM_ERROR;
+ trv = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
+ r = Z_BUF_ERROR;
+ while (1) switch (z->state->mode)
+ {
+ case METHOD:
+ NEEDBYTE
+ if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED)
+ {
+ z->state->mode = I_BAD;
+ z->msg = (char*)"unknown compression method";
+ z->state->sub.marker = 5; /* can't try inflateSync */
+ break;
+ }
+ if ((z->state->sub.method >> 4) + 8 > z->state->wbits)
+ {
+ z->state->mode = I_BAD;
+ z->msg = (char*)"invalid window size";
+ z->state->sub.marker = 5; /* can't try inflateSync */
+ break;
+ }
+ z->state->mode = FLAG;
+ case FLAG:
+ NEEDBYTE
+ b = NEXTBYTE;
+ if (((z->state->sub.method << 8) + b) % 31)
+ {
+ z->state->mode = I_BAD;
+ z->msg = (char*)"incorrect header check";
+ z->state->sub.marker = 5; /* can't try inflateSync */
+ break;
+ }
+ if (!(b & PRESET_DICT))
+ {
+ z->state->mode = BLOCKS;
+ break;
+ }
+ z->state->mode = DICT4;
+ case DICT4:
+ NEEDBYTE
+ z->state->sub.check.need = (uLong)NEXTBYTE << 24;
+ z->state->mode = DICT3;
+ case DICT3:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE << 16;
+ z->state->mode = DICT2;
+ case DICT2:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE << 8;
+ z->state->mode = DICT1;
+ case DICT1:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE;
+ z->adler = z->state->sub.check.need;
+ z->state->mode = DICT0;
+ return Z_NEED_DICT;
+ case DICT0:
+ z->state->mode = I_BAD;
+ z->msg = (char*)"need dictionary";
+ z->state->sub.marker = 0; /* can try inflateSync */
+ return Z_STREAM_ERROR;
+ case BLOCKS:
+ r = zlib_inflate_blocks(z->state->blocks, z, r);
+ if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0)
+ r = zlib_inflate_packet_flush(z->state->blocks);
+ if (r == Z_DATA_ERROR)
+ {
+ z->state->mode = I_BAD;
+ z->state->sub.marker = 0; /* can try inflateSync */
+ break;
+ }
+ if (r == Z_OK)
+ r = trv;
+ if (r != Z_STREAM_END)
+ return r;
+ r = trv;
+ zlib_inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was);
+ if (z->state->nowrap)
+ {
+ z->state->mode = I_DONE;
+ break;
+ }
+ z->state->mode = CHECK4;
+ case CHECK4:
+ NEEDBYTE
+ z->state->sub.check.need = (uLong)NEXTBYTE << 24;
+ z->state->mode = CHECK3;
+ case CHECK3:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE << 16;
+ z->state->mode = CHECK2;
+ case CHECK2:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE << 8;
+ z->state->mode = CHECK1;
+ case CHECK1:
+ NEEDBYTE
+ z->state->sub.check.need += (uLong)NEXTBYTE;
+
+ if (z->state->sub.check.was != z->state->sub.check.need)
+ {
+ z->state->mode = I_BAD;
+ z->msg = (char*)"incorrect data check";
+ z->state->sub.marker = 5; /* can't try inflateSync */
+ break;
+ }
+ z->state->mode = I_DONE;
+ case I_DONE:
+ return Z_STREAM_END;
+ case I_BAD:
+ return Z_DATA_ERROR;
+ default:
+ return Z_STREAM_ERROR;
+ }
+ empty:
+ if (f != Z_PACKET_FLUSH)
+ return r;
+ z->state->mode = I_BAD;
+ z->msg = (char *)"need more for packet flush";
+ z->state->sub.marker = 0; /* can try inflateSync */
+ return Z_DATA_ERROR;
+}