split CBFS support into shared core and extended functions

The core is data structures and basic file finding capabilities,
while option ROM handling, and loading stages and payloads is
"extended".

The core is rewritten to be BSD-l (its header already was), so
can be copied to libpayload verbatim.
It's also more robust in finding files in corrupted images, eg.
after partial erase or update.

Change-Id: Ic6923debf8bdf3c67c75746d3b31f3addab3dd74
Signed-off-by: Patrick Georgi <patrick.georgi@secunet.com>
Reviewed-on: http://review.coreboot.org/114
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

4 files changed, 369 insertions, 226 deletions

diff --git a/src/include/cbfs.h b/src/include/cbfs.h
index c1c1e33743..148317702a 100644
--- a/src/include/cbfs.h
+++ b/src/include/cbfs.h
@@ -49,130 +49,13 @@
 #ifndef _CBFS_H_
 #define _CBFS_H_
 
+#include "cbfs_core.h"
 #include <boot/coreboot_tables.h>
-/** These are standard values for the known compression
-    alogrithms that coreboot knows about for stages and
-    payloads.  Of course, other CBFS users can use whatever
-    values they want, as long as they understand them. */
 
-#define CBFS_COMPRESS_NONE  0
-#define CBFS_COMPRESS_LZMA  1
-
-/** These are standard component types for well known
-    components (i.e - those that coreboot needs to consume.
-    Users are welcome to use any other value for their
-    components */
-
-#define CBFS_TYPE_STAGE      0x10
-#define CBFS_TYPE_PAYLOAD    0x20
-#define CBFS_TYPE_OPTIONROM  0x30
-#define CBFS_TYPE_BOOTSPLASH 0x40
-#define CBFS_TYPE_RAW        0x50
-#define CBFS_TYPE_VSA        0x51
-#define CBFS_TYPE_MBI        0x52
-#define CBFS_TYPE_MICROCODE  0x53
-#define CBFS_COMPONENT_CMOS_DEFAULT 0xaa
-#define CBFS_COMPONENT_CMOS_LAYOUT 0x01aa
-
-
-/** this is the master cbfs header - it need to be
-    located somewhere in the bootblock.  Where it
-    actually lives is up to coreboot. A pointer to
-    this header will live at 0xFFFFFFFc, so we can
-    easily find it. */
-
-#define CBFS_HEADER_MAGIC  0x4F524243
-#define CBFS_HEADPTR_ADDR 0xFFFFFFFc
-#define VERSION1 0x31313131
-
-struct cbfs_header {
-	u32 magic;
-        u32 version;
-        u32 romsize;
-        u32 bootblocksize;
-	u32 align;
-	u32 offset;
-	u32 pad[2];
-} __attribute__((packed));
-
-/** This is a component header - every entry in the CBFS
-    will have this header.
-
-    This is how the component is arranged in the ROM:
-
-    --------------   <- 0
-    component header
-    --------------   <- sizeof(struct component)
-    component name
-    --------------   <- offset
-    data
-    ...
-    --------------   <- offset + len
-*/
-
-#define CBFS_FILE_MAGIC "LARCHIVE"
-
-struct cbfs_file {
-	char magic[8];
-	u32 len;
-	u32 type;
-	u32 checksum;
-	u32 offset;
-} __attribute__((packed));
-
-/*** Component sub-headers ***/
-
-/* Following are component sub-headers for the "standard"
-   component types */
-
-/** This is the sub-header for stage components.  Stages are
-    loaded by coreboot during the normal boot process */
-
-struct cbfs_stage {
-	u32 compression;  /** Compression type */
-	u64 entry;  /** entry point */
-	u64 load;   /** Where to load in memory */
-	u32 len;          /** length of data to load */
-	u32 memlen;	   /** total length of object in memory */
-} __attribute__((packed));
-
-/** this is the sub-header for payload components.  Payloads
-    are loaded by coreboot at the end of the boot process */
-
-struct cbfs_payload_segment {
-	u32 type;
-	u32 compression;
-	u32 offset;
-	u64 load_addr;
-	u32 len;
-	u32 mem_len;
-} __attribute__((packed));
-
-struct cbfs_payload {
-	struct cbfs_payload_segment segments;
-};
-
-#define PAYLOAD_SEGMENT_CODE   0x45444F43
-#define PAYLOAD_SEGMENT_DATA   0x41544144
-#define PAYLOAD_SEGMENT_BSS    0x20535342
-#define PAYLOAD_SEGMENT_PARAMS 0x41524150
-#define PAYLOAD_SEGMENT_ENTRY  0x52544E45
-
-struct cbfs_optionrom {
-	u32 compression;
-	u32 len;
-} __attribute__((packed));
-
-#define CBFS_NAME(_c) (((char *) (_c)) + sizeof(struct cbfs_file))
-#define CBFS_SUBHEADER(_p) ( (void *) ((((u8 *) (_p)) + ntohl((_p)->offset))) )
-
-void * cbfs_load_payload(struct lb_memory *lb_mem, const char *name);
-void * cbfs_load_stage(const char *name);
+void *cbfs_load_payload(struct lb_memory *lb_mem, const char *name);
+void *cbfs_load_stage(const char *name);
 int cbfs_execute_stage(const char *name);
-void * cbfs_get_file(const char *name);
 void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest);
 int run_address(void *f);
-struct cbfs_file *cbfs_find(const char *name);
-void *cbfs_find_file(const char *name, int type);
 #endif
 
diff --git a/src/include/cbfs_core.h b/src/include/cbfs_core.h
new file mode 100644
index 0000000000..fbe0081517
--- /dev/null
+++ b/src/include/cbfs_core.h
@@ -0,0 +1,180 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2008 Jordan Crouse <jordan@cosmicpenguin.net>
+ *
+ * This file is dual-licensed. You can choose between:
+ *   - The GNU GPL, version 2, as published by the Free Software Foundation
+ *   - The revised BSD license (without advertising clause)
+ *
+ * ---------------------------------------------------------------------------
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
+ * ---------------------------------------------------------------------------
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ---------------------------------------------------------------------------
+ */
+
+#ifndef _CBFS_CORE_H_
+#define _CBFS_CORE_H_
+
+/** These are standard values for the known compression
+    alogrithms that coreboot knows about for stages and
+    payloads.  Of course, other CBFS users can use whatever
+    values they want, as long as they understand them. */
+
+#define CBFS_COMPRESS_NONE  0
+#define CBFS_COMPRESS_LZMA  1
+
+/** These are standard component types for well known
+    components (i.e - those that coreboot needs to consume.
+    Users are welcome to use any other value for their
+    components */
+
+#define CBFS_TYPE_STAGE      0x10
+#define CBFS_TYPE_PAYLOAD    0x20
+#define CBFS_TYPE_OPTIONROM  0x30
+#define CBFS_TYPE_BOOTSPLASH 0x40
+#define CBFS_TYPE_RAW        0x50
+#define CBFS_TYPE_VSA        0x51
+#define CBFS_TYPE_MBI        0x52
+#define CBFS_TYPE_MICROCODE  0x53
+#define CBFS_COMPONENT_CMOS_DEFAULT 0xaa
+#define CBFS_COMPONENT_CMOS_LAYOUT 0x01aa
+
+
+/** this is the master cbfs header - it need to be
+    located somewhere in the bootblock.  Where it
+    actually lives is up to coreboot. A pointer to
+    this header will live at 0xFFFFFFFc, so we can
+    easily find it. */
+
+#define CBFS_HEADER_MAGIC  0x4F524243
+#define CBFS_HEADPTR_ADDR 0xFFFFFFFc
+#define VERSION1 0x31313131
+
+struct cbfs_header {
+	uint32_t magic;
+	uint32_t version;
+	uint32_t romsize;
+	uint32_t bootblocksize;
+	uint32_t align;
+	uint32_t offset;
+	uint32_t pad[2];
+} __attribute__((packed));
+
+/** This is a component header - every entry in the CBFS
+    will have this header.
+
+    This is how the component is arranged in the ROM:
+
+    --------------   <- 0
+    component header
+    --------------   <- sizeof(struct component)
+    component name
+    --------------   <- offset
+    data
+    ...
+    --------------   <- offset + len
+*/
+
+#define CBFS_FILE_MAGIC "LARCHIVE"
+
+struct cbfs_file {
+	char magic[8];
+	uint32_t len;
+	uint32_t type;
+	uint32_t checksum;
+	uint32_t offset;
+} __attribute__((packed));
+
+/*** Component sub-headers ***/
+
+/* Following are component sub-headers for the "standard"
+   component types */
+
+/** This is the sub-header for stage components.  Stages are
+    loaded by coreboot during the normal boot process */
+
+struct cbfs_stage {
+	uint32_t compression;  /** Compression type */
+	uint64_t entry;  /** entry point */
+	uint64_t load;   /** Where to load in memory */
+	uint32_t len;          /** length of data to load */
+	uint32_t memlen;	   /** total length of object in memory */
+} __attribute__((packed));
+
+/** this is the sub-header for payload components.  Payloads
+    are loaded by coreboot at the end of the boot process */
+
+struct cbfs_payload_segment {
+	uint32_t type;
+	uint32_t compression;
+	uint32_t offset;
+	uint64_t load_addr;
+	uint32_t len;
+	uint32_t mem_len;
+} __attribute__((packed));
+
+struct cbfs_payload {
+	struct cbfs_payload_segment segments;
+};
+
+#define PAYLOAD_SEGMENT_CODE   0x45444F43
+#define PAYLOAD_SEGMENT_DATA   0x41544144
+#define PAYLOAD_SEGMENT_BSS    0x20535342
+#define PAYLOAD_SEGMENT_PARAMS 0x41524150
+#define PAYLOAD_SEGMENT_ENTRY  0x52544E45
+
+struct cbfs_optionrom {
+	uint32_t compression;
+	uint32_t len;
+} __attribute__((packed));
+
+#define CBFS_NAME(_c) (((char *) (_c)) + sizeof(struct cbfs_file))
+#define CBFS_SUBHEADER(_p) ( (void *) ((((uint8_t *) (_p)) + ntohl((_p)->offset))) )
+
+/* returns pointer to file inside CBFS or NULL */
+struct cbfs_file *cbfs_find(const char *name);
+
+/* returns pointer to file data inside CBFS */
+void *cbfs_get_file(const char *name);
+
+/* returns pointer to file data inside CBFS after if type is correct */
+void *cbfs_find_file(const char *name, int type);
+
+/* returns 0 on success, -1 on failure */
+int cbfs_decompress(int algo, void *src, void *dst, int len);
+#endif
+
diff --git a/src/lib/cbfs.c b/src/lib/cbfs.c
index 7cfa3e2a40..20c9d4957a 100644
--- a/src/lib/cbfs.c
+++ b/src/lib/cbfs.c
@@ -24,85 +24,19 @@
 #include <lib.h>
 #include <arch/byteorder.h>
 
+// use CBFS core
+#ifndef __SMM__
+#define CBFS_CORE_WITH_LZMA
+#endif
+#define phys_to_virt(x) (void*)(x)
+#define virt_to_phys(x) (uint32_t)(x)
+#define ERROR(x...) printk(BIOS_ERR, x)
+#define LOG(x...) printk(BIOS_INFO, x)
+// FIXME: romstart/romend are fine on x86, but not on ARM
+#define romstart() 0xffffffff
+#define romend() 0
 
-static int cbfs_check_magic(struct cbfs_file *file)
-{
-	return !strcmp(file->magic, CBFS_FILE_MAGIC) ? 1 : 0;
-}
-
-static struct cbfs_header *cbfs_master_header(void)
-{
-	struct cbfs_header *header;
-
-	void *ptr = (void *)*((unsigned long *) CBFS_HEADPTR_ADDR);
-	printk(BIOS_SPEW, "Check CBFS header at %p\n", ptr);
-	header = (struct cbfs_header *) ptr;
-
-	printk(BIOS_SPEW, "magic is %08x\n", ntohl(header->magic));
-	if (ntohl(header->magic) != CBFS_HEADER_MAGIC) {
-		printk(BIOS_ERR, "ERROR: No valid CBFS header found!\n");
-		if (header->magic == 0xffffffff) {
-			printk(BIOS_ERR, "Maybe the ROM isn't entirely mapped yet?\n"
-				"See (and report to) http://www.coreboot.org/Infrastructure_Projects#CBFS\n");
-		}
-		return NULL;
-	}
-
-	printk(BIOS_SPEW, "Found CBFS header at %p\n", ptr);
-	return header;
-}
-
-struct cbfs_file *cbfs_find(const char *name)
-{
-	struct cbfs_header *header = cbfs_master_header();
-	unsigned long offset;
-
-	if (header == NULL)
-		return NULL;
-	offset = 0 - ntohl(header->romsize) + ntohl(header->offset);
-
-	int align= ntohl(header->align);
-
-	while(1) {
-		struct cbfs_file *file = (struct cbfs_file *) offset;
-		if (!cbfs_check_magic(file)) return NULL;
-		printk(BIOS_SPEW, "Check %s\n", CBFS_NAME(file));
-		if (!strcmp(CBFS_NAME(file), name))
-			return file;
-
-		int flen = ntohl(file->len);
-		int foffset = ntohl(file->offset);
-		printk(BIOS_SPEW, "CBFS: follow chain: %p + %x + %x + align -> ", (void *)offset, foffset, flen);
-
-		unsigned long oldoffset = offset;
-		offset = ALIGN(offset + foffset + flen, align);
-		printk(BIOS_SPEW, "%p\n", (void *)offset);
-		if (offset <= oldoffset) return NULL;
-
-		if (offset < 0xFFFFFFFF - ntohl(header->romsize))
-			return NULL;
-	}
-}
-
-void *cbfs_find_file(const char *name, int type)
-{
-	struct cbfs_file *file = cbfs_find(name);
-
-	if (file == NULL) {
-		printk(BIOS_INFO,  "CBFS:  Could not find file %s\n",
-		       name);
-		return NULL;
-	}
-
-	if (ntohl(file->type) != type) {
-		printk(BIOS_INFO,  "CBFS:  File %s is of type %x instead of"
-		       "type %x\n", name, file->type, type);
-
-		return NULL;
-	}
-
-	return (void *) CBFS_SUBHEADER(file);
-}
+#include "cbfs_core.c"
 
 #ifndef __SMM__
 static inline int tohex4(unsigned int c)
@@ -118,34 +52,6 @@ static void tohex16(unsigned int val, char* dest)
 	dest[3]=tohex4(val & 0xf);
 }
 
-/**
- * Decompression wrapper for CBFS
- * @param algo
- * @param src
- * @param dst
- * @param len
- * @return 0 on success, -1 on failure
- */
-static int cbfs_decompress(int algo, void *src, void *dst, int len)
-{
-	switch(algo) {
-	case CBFS_COMPRESS_NONE:
-		memcpy(dst, src, len);
-		return 0;
-
-	case CBFS_COMPRESS_LZMA:
-		if (!ulzma(src, dst)) {
-			printk(BIOS_ERR, "CBFS: LZMA decompression failed!\n");
-			return -1;
-		}
-		return 0;
-	default:
-		printk(BIOS_INFO,  "CBFS:  Unknown compression type %d\n", algo);
-		return -1;
-	}
-}
-
-
 void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest)
 {
 	char name[17]="pciXXXX,XXXX.rom";
diff --git a/src/lib/cbfs_core.c b/src/lib/cbfs_core.c
new file mode 100644
index 0000000000..52ba58ded7
--- /dev/null
+++ b/src/lib/cbfs_core.c
@@ -0,0 +1,174 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2011 secunet Security Networks AG
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* The CBFS core requires a couple of #defines or functions to adapt it to the target environment:
+ *
+ * CBFS_CORE_WITH_LZMA (must be #define)
+ *      if defined, ulzma() must exist for decompression of data streams
+ *
+ * phys_to_virt(x), virt_to_phys(x)
+ *      translate physical addresses to virtual and vice versa
+ *      can be idempotent if no mapping is necessary.
+ *
+ * ERROR(x...)
+ *      print an error message x (in printf format)
+ *
+ * LOG(x...)
+ *      print a debug message x (in printf format)
+ *
+ * romstart()
+ *      returns the start address of the ROM image, or 0xffffffff if ROM is
+ *      top-aligned. This is a physical address.
+ *
+ * romend()
+ *      returns the highest address of the ROM image + 1, for use if
+ *      romstart() == 0xffffffff. This is a physical address.
+ */
+
+#include <cbfs_core.h>
+
+
+/* returns pointer to master header or 0xffffffff if not found */
+static struct cbfs_header *get_cbfs_header(void)
+{
+	struct cbfs_header *header;
+
+	/* find header */
+	if (romstart() == 0xffffffff) {
+		header = (struct cbfs_header*)phys_to_virt(*(uint32_t*)phys_to_virt(romend() + CBFS_HEADPTR_ADDR));
+	} else {
+		// FIXME: where's the master header on ARM (our current bottom-aligned platform)?
+		header = NULL;
+	}
+	if (CBFS_HEADER_MAGIC != ntohl(header->magic)) {
+		ERROR("Could not find valid CBFS master header at %p: %x vs %x.\n", header, CBFS_HEADER_MAGIC, ntohl(header->magic));
+		if (header->magic == 0xffffffff) {
+			ERROR("Maybe ROM is not mapped properly?\n");
+		}
+		return (void*)0xffffffff;
+	}
+	return header;
+}
+
+// by must be power-of-two
+#define CBFS_ALIGN(val, by) (typeof(val))((uint32_t)(val + by - 1) & (uint32_t)~(by - 1))
+#define CBFS_ALIGN_UP(val, by) CBFS_ALIGN(val + 1, by)
+
+/* public API starts here*/
+struct cbfs_file *cbfs_find(const char *name)
+{
+	struct cbfs_header *header = get_cbfs_header();
+	if (header == (void*)0xffffffff) return NULL;
+
+	LOG("Searching for %s\n", name);
+
+	void *data, *dataend, *origdata;
+	/* find first entry */
+	if (romstart() == 0xffffffff) {
+		data = (void*)phys_to_virt(romend()) - ntohl(header->romsize) + ntohl(header->offset);
+		dataend = (void*)phys_to_virt(romend());
+	} else {
+		data = (void*)phys_to_virt(romstart()) + ntohl(header->offset);
+		dataend = (void*)phys_to_virt(romstart()) + ntohl(header->romsize);
+	}
+
+	int align = ntohl(header->align);
+
+	origdata = data;
+	while ((data < (dataend - 1)) && (data >= origdata)) {
+		struct cbfs_file *file = data;
+		if (memcmp(CBFS_FILE_MAGIC, file->magic, strlen(CBFS_FILE_MAGIC)) != 0) {
+			// no file header found. corruption?
+			// proceed in aligned steps to resynchronize
+			LOG("No file header found at %p, searching for header\n", data);
+			data = phys_to_virt(CBFS_ALIGN_UP(virt_to_phys(data), align));
+			continue;
+		}
+		LOG("Check %s\n", CBFS_NAME(file));
+		if (strcmp(CBFS_NAME(file), name) == 0) {
+			return file;
+		}
+		void *olddata = data;
+		data = phys_to_virt(CBFS_ALIGN(virt_to_phys(data) + ntohl(file->len) + ntohl(file->offset), align));
+		if (olddata > data) {
+			LOG("Something is wrong here. File chain moved from %p to %p\n", olddata, data);
+			return NULL;
+		}
+	}
+	return NULL;
+}
+
+void *cbfs_get_file(const char *name)
+{
+	struct cbfs_file *file = cbfs_find(name);
+
+	if (file == NULL) {
+		ERROR("Could not find file '%s'.\n", name);
+		return NULL;
+	}
+
+	return (void*)CBFS_SUBHEADER(file);
+}
+
+void *cbfs_find_file(const char *name, int type)
+{
+	struct cbfs_file *file = cbfs_find(name);
+
+	if (file == NULL) {
+		ERROR("Could not find file '%s'.\n", name);
+		return NULL;
+	}
+
+	if (ntohl(file->type) != type) {
+		ERROR("File '%s' is of type %x, but we requested %x.\n", name, ntohl(file->type), type);
+		return NULL;
+	}
+
+	return (void*)CBFS_SUBHEADER(file);
+}
+
+int cbfs_decompress(int algo, void *src, void *dst, int len)
+{
+	switch (algo) {
+		case CBFS_COMPRESS_NONE:
+			memcpy(dst, src, len);
+			return 0;
+#ifdef CBFS_CORE_WITH_LZMA
+		case CBFS_COMPRESS_LZMA:
+			if (ulzma(src, dst) != 0) {
+				return 0;
+			}
+			return -1;
+#endif
+		default:
+			ERROR("tried to decompress %d bytes with algorithm #%x, but that algorithm id is unsupported.\n", len, algo);
+			return -1;
+	}
+}
+