commit 0834c59d0628ddf55e99eb06141c2bbdfe05d438
author Janos Follath <janos.follath@arm.com> Fri Jan 24 09:44:31 2025 +0000
committer GitHub <noreply@github.com> Fri Jan 24 09:44:31 2025 +0000
tree 9539b7dda51acad2dcfc57a556188edba7dc565a
parent 32fe8f3cf174840c11413966f9a299a1c9232a8c
parent 49d440372f22f1fe19b7a01a1db7a4e7613fe0a0

Merge pull request #9496 from minosgalanakis/doc/add_mbedtls_ecp_check_privkey_comment_bp28

[Backport 2.28] Refactored a minor check in ecp check privkey

library/ecp.c

diff --git a/library/ecp.c b/library/ecp.c
index cfe02b0..2ed735d 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -3125,7 +3125,7 @@
         /* see RFC 7748 sec. 5 para. 5 */
         if (mbedtls_mpi_get_bit(d, 0) != 0 ||
             mbedtls_mpi_get_bit(d, 1) != 0 ||
-            mbedtls_mpi_bitlen(d) - 1 != grp->nbits) {  /* mbedtls_mpi_bitlen is one-based! */
+            mbedtls_mpi_bitlen(d) != grp->nbits + 1) {  /* mbedtls_mpi_bitlen is one-based! */
             return MBEDTLS_ERR_ECP_INVALID_KEY;
         }