1 // SPDX-License-Identifier: GPL-2.0-or-later
5 * This utility creates Netgear .chk files.
7 * Copyright (C) 2008 Dave C. Reeve <Dave.Reeve@dreeve.org>
14 #include <arpa/inet.h>
17 #define BUF_LEN (2048)
19 #define MAX_BOARD_ID_LEN (64)
22 * Note on the reserved field of the chk_header:
23 * OFW naming scheme is typically: DEVICENAME-VA.B.C.D_E.F.G.chk, with A-G
24 * between 0 and 255. For instance: EX3700_EX3800-V1.0.0.58_1.0.38.chk
25 * The reserved field works like this:
26 * reserved[0]: region code. 1 for WW (WorldWide) and 2 for NA (North America)
39 uint32_t kernel_chksum
;
40 uint32_t rootfs_chksum
;
43 uint32_t image_chksum
;
44 uint32_t header_chksum
;
45 /* char board_id[] - upto MAX_BOARD_ID_LEN */
48 static void __attribute__ ((format (printf
, 2, 3)))
49 fatal_error (int maybe_errno
, const char * format
, ...)
53 fprintf (stderr
, "mkchkimg: ");
54 va_start (ap
, format
);
55 vfprintf (stderr
, format
, ap
);
59 fprintf (stderr
, ": %s\n", strerror (maybe_errno
));
61 fprintf (stderr
, "\n");
67 static void __attribute__ ((format (printf
, 1, 2)))
68 message (const char * format
, ...)
72 fprintf (stderr
, "mkchkimg: ");
73 va_start (ap
, format
);
74 vfprintf (stderr
, format
, ap
);
76 fprintf (stderr
, "\n");
85 netgear_checksum_init (struct ngr_checksum
* c
)
91 netgear_checksum_add (struct ngr_checksum
* c
, unsigned char * buf
, size_t len
)
95 for (i
=0; i
<len
; i
++) {
96 c
->c0
+= buf
[i
] & 0xff;
101 static inline unsigned long
102 netgear_checksum_fini (struct ngr_checksum
* c
)
104 uint32_t b
, checksum
;
106 b
= (c
->c0
& 65535) + ((c
->c0
>> 16) & 65535);
107 c
->c0
= ((b
>> 16) + b
) & 65535;
108 b
= (c
->c1
& 65535) + ((c
->c1
>> 16) & 65535);
109 c
->c1
= ((b
>> 16) + b
) & 65535;
110 checksum
= ((c
->c1
<< 16) | c
->c0
);
117 fprintf (stderr
, "Usage: mkchkimg -o output -k kernel [-f filesys] [-b board_id] [-r region]\n");
121 main (int argc
, char * argv
[])
127 struct chk_header
* hdr
;
128 struct ngr_checksum chk_part
, chk_whole
;
130 char * output_file
, * kern_file
, * fs_file
;
131 FILE * out_fp
, * kern_fp
, * fs_fp
;
133 unsigned long region
;
136 board_id
= "U12H072T00_NETGEAR";
137 region
= 1; /* 1=WW, 2=NA */
143 while ((opt
= getopt (argc
, argv
, ":b:r:k:f:o:h")) != -1) {
147 if (strlen (optarg
) > MAX_BOARD_ID_LEN
) {
148 fatal_error (0, "Board lenght exceeds %d",
157 region
= strtoul (optarg
, &ptr
, 0);
158 if (errno
|| ptr
==optarg
|| *ptr
!='\0') {
159 fatal_error (0, "Cannot parse region %s", optarg
);
162 fatal_error (0, "Region cannot exceed 0xff");
178 output_file
= optarg
;
187 fatal_error (0, "Option -%c missing argument", optopt
);
192 fatal_error (0, "Unknown argument -%c", optopt
);
200 /* Check we have all the options expected */
203 fatal_error (0, "Kernel file expected");
207 fatal_error (0, "Output file required");
209 message ("Netgear CHK writer - v0.1");
211 /* Open the input file */
212 kern_fp
= fopen (kern_file
, "r");
214 fatal_error (errno
, "Cannot open %s", kern_file
);
217 /* Open the fs file, if specified */
219 fs_fp
= fopen (fs_file
, "r");
222 fatal_error (errno
, "Cannot open %s", fs_file
);
226 /* Open the output file */
227 out_fp
= fopen (output_file
, "w+");
233 fatal_error (errno
, "Cannot open %s", output_file
);
236 /* Write zeros when the chk header will be */
238 header_len
= sizeof (struct chk_header
) + strlen (board_id
);
239 if (fwrite (buf
, 1, header_len
, out_fp
) != header_len
) {
240 fatal_error (errno
, "Cannot write header");
243 /* Allocate storage for header, we fill in as we go */
244 hdr
= malloc (sizeof (struct chk_header
));
246 fatal_error (0, "malloc failed");
248 bzero (hdr
, sizeof (struct chk_header
));
250 /* Fill in known values */
251 hdr
->magic
= htonl (0x2a23245e);
252 hdr
->header_len
= htonl(header_len
);
253 hdr
->reserved
[0] = (unsigned char)(region
& 0xff);
254 memset(&hdr
->reserved
[1], 99, sizeof(hdr
->reserved
) - 1);
256 message (" Board Id: %s", board_id
);
257 message (" Region: %s", region
== 1 ? "World Wide (WW)"
258 : (region
== 2 ? "North America (NA)" : "Unknown"));
260 /* Copy the trx file, calculating the checksum as we go */
261 netgear_checksum_init (&chk_part
);
262 netgear_checksum_init (&chk_whole
);
263 while (!feof (kern_fp
)) {
264 len
= fread (buf
, 1, BUF_LEN
, kern_fp
);
268 if (fwrite (buf
, len
, 1, out_fp
) != 1) {
269 fatal_error (errno
, "Write error");
271 hdr
->kernel_len
+= len
;
272 netgear_checksum_add (&chk_part
, (unsigned char *)buf
, len
);
273 netgear_checksum_add (&chk_whole
, (unsigned char *)buf
, len
);
276 hdr
->kernel_chksum
= netgear_checksum_fini (&chk_part
);
277 message (" Kernel Len: %u", hdr
->kernel_len
);
278 message ("Kernel Checksum: 0x%08x", hdr
->kernel_chksum
);
279 hdr
->kernel_len
= htonl (hdr
->kernel_len
);
280 hdr
->kernel_chksum
= htonl (hdr
->kernel_chksum
);
282 /* Now copy the root fs, calculating the checksum as we go */
284 netgear_checksum_init (&chk_part
);
285 while (!feof (fs_fp
)) {
286 len
= fread (buf
, 1, BUF_LEN
, fs_fp
);
290 if (fwrite (buf
, len
, 1, out_fp
) != 1) {
291 fatal_error (errno
, "Write error");
293 hdr
->rootfs_len
+= len
;
294 netgear_checksum_add (&chk_part
, (unsigned char *)buf
, len
);
295 netgear_checksum_add (&chk_whole
, (unsigned char *)buf
, len
);
298 hdr
->rootfs_chksum
= (netgear_checksum_fini (&chk_part
));
299 message (" Rootfs Len: %u", hdr
->rootfs_len
);
300 message ("Rootfs Checksum: 0x%08x", hdr
->rootfs_chksum
);
301 hdr
->rootfs_len
= htonl (hdr
->rootfs_len
);
302 hdr
->rootfs_chksum
= htonl (hdr
->rootfs_chksum
);
305 /* Calcautate the image checksum */
306 hdr
->image_chksum
= netgear_checksum_fini (&chk_whole
);
307 message (" Image Checksum: 0x%08x", hdr
->image_chksum
);
308 hdr
->image_chksum
= htonl (hdr
->image_chksum
);
310 /* Calculate the header checksum */
311 netgear_checksum_init (&chk_part
);
312 netgear_checksum_add (&chk_part
, (unsigned char *)hdr
,
313 sizeof (struct chk_header
));
314 netgear_checksum_add (&chk_part
, (unsigned char *)board_id
,
316 hdr
->header_chksum
= htonl (netgear_checksum_fini (&chk_part
));
318 /* Finally rewind the output and write headers */
320 if (fwrite (hdr
, sizeof (struct chk_header
), 1, out_fp
) != 1) {
321 fatal_error (errno
, "Cannot write header");
323 if (fwrite (board_id
, strlen (board_id
), 1, out_fp
) != 1) {
324 fatal_error (errno
, "Cannot write board id");