Add "cbfstool extract" function.

It dumps everything you ask for, but you might not
get what you expect if the file is compressed or
otherwise converted (eg. payloads in SELF format).
(Originally it would only extract "raw" files.
This is a change by me, as filetypes are commonly used
to differentiate raw data files --Patrick)

Signed-off-by: Aurelien Guillaume <aurelien@iwi.me>
Signed-off-by: Patrick Georgi <patrick.georgi@secunet.com>
Acked-by: Patrick Georgi <patrick.georgi@secunet.com>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@6250 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

util/cbfstool/common.c

@@ -207,6 +207,69 @@ void print_cbfs_directory(const char *filename)
 	}
 }
 
+int extract_file_from_cbfs(const char *filename, const char *payloadname, const char *outpath)
+{
+	// Identify the coreboot image.
+	printf(
+	     "%s: %d kB, bootblocksize %d, romsize %d, offset 0x%x\nAlignment: %d bytes\n\n",
+	     basename((char *)filename), romsize / 1024, ntohl(master_header->bootblocksize),
+	     romsize, ntohl(master_header->offset), align);
+
+	FILE *outfile = NULL;
+	uint32_t current = phys_start;
+	while (current < phys_end) {
+		if (!cbfs_file_header(current)) {
+			current += align;
+			continue;
+		}
+
+		// Locate the file start struct
+		struct cbfs_file *thisfile =
+		    (struct cbfs_file *)phys_to_virt(current);
+		// And its length
+		uint32_t length = ntohl(thisfile->len);
+		// Locate the file name
+		char *fname = (char *)(phys_to_virt(current) + sizeof(struct cbfs_file));
+		// It's not the file we are looking for..
+		if (strcmp(fname, payloadname) != 0)
+		{
+			current =
+			   ALIGN(current + ntohl(thisfile->len) +
+				  ntohl(thisfile->offset), align);
+			continue;
+		}
+
+		// Else, it's our file.
+		printf("Found %.30s payload at 0x%x, type %.12s, size %d\n", fname,
+		       current - phys_start, strfiletype(ntohl(thisfile->type)),
+		       length);
+
+		// If we are not dumping to stdout, open the out file.
+		outfile = fopen(outpath, "wb");
+		if (!outfile)
+		{
+			printf("Could not open the file %s for writing. Aborting.\n", outpath);
+			return 1;
+		}
+
+		if (ntohl(thisfile->type) != CBFS_COMPONENT_RAW)
+		{
+			printf("Warning: only 'raw' files are safe to extract.\n");
+		}
+
+		fwrite(((char *)thisfile)
+				+ ntohl(thisfile->offset), length, 1, outfile);
+
+		fclose(outfile);
+		printf("Successfully dumped the payload.\n");
+
+		// We'll only dump one file.
+		return 0;
+	}
+
+}
+
+
 int add_file_to_cbfs(void *content, uint32_t contentsize, uint32_t location)
 {
 	uint32_t current = phys_start;