On 25.10.21 15:12, Marek Behún wrote:
From: Pali Rohár <p...@kernel.org>

Data part of the image contains 4-byte checksum. Validate it when
processing the image.

Signed-off-by: Pali Rohár <p...@kernel.org>
[ refactored ]
Signed-off-by: Marek Behún <marek.be...@nic.cz>

Reviewed-by: Stefan Roese <s...@denx.de>

Thanks,
Stefan

---
  tools/kwboot.c | 34 ++++++++++++++++++++++++++++++++++
  1 file changed, 34 insertions(+)

diff --git a/tools/kwboot.c b/tools/kwboot.c
index 4e29317f10..bc44301535 100644
--- a/tools/kwboot.c
+++ b/tools/kwboot.c
@@ -1251,6 +1251,37 @@ kwboot_hdr_csum8(const void *hdr)
        return csum;
  }
+static uint32_t *
+kwboot_img_csum32_ptr(void *img)
+{
+       struct main_hdr_v1 *hdr = img;
+       uint32_t datasz;
+
+       datasz = le32_to_cpu(hdr->blocksize) - sizeof(uint32_t);
+
+       return img + le32_to_cpu(hdr->srcaddr) + datasz;
+}
+
+static uint32_t
+kwboot_img_csum32(const void *img)
+{
+       const struct main_hdr_v1 *hdr = img;
+       uint32_t datasz, csum = 0;
+       const uint32_t *data;
+
+       datasz = le32_to_cpu(hdr->blocksize) - sizeof(csum);
+       if (datasz % sizeof(uint32_t))
+               return 0;
+
+       data = img + le32_to_cpu(hdr->srcaddr);
+       while (datasz > 0) {
+               csum += le32_to_cpu(*data++);
+               datasz -= 4;
+       }
+
+       return cpu_to_le32(csum);
+}
+
  static int
  kwboot_img_is_secure(void *img)
  {
@@ -1462,6 +1493,9 @@ kwboot_img_patch(void *img, size_t *size, int baudrate)
            *size < le32_to_cpu(hdr->srcaddr) + le32_to_cpu(hdr->blocksize))
                goto err;
+ if (kwboot_img_csum32(img) != *kwboot_img_csum32_ptr(img))
+               goto err;
+
        is_secure = kwboot_img_is_secure(img);
if (hdr->blockid != IBR_HDR_UART_ID) {



Viele Grüße,
Stefan

--
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: s...@denx.de

Reply via email to