commit d56e6e008bb5979c68d8710b5a992b664dc9212c
author Gabor Mezei <gabor.mezei@arm.com> Wed May 17 17:51:19 2023 +0200
committer Gabor Mezei <gabor.mezei@arm.com> Wed May 17 17:51:19 2023 +0200
tree a7ab061eb79739fe5cbb15548748a3a55aae5208
parent fa3f74145b21d9d9c827a016bcc5b6d355a0afd1

Add input parameter length check for the Koblitz reduction

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>

library/ecp_curves.c

diff --git a/library/ecp_curves.c b/library/ecp_curves.c
index 1496970..6573f89 100644
--- a/library/ecp_curves.c
+++ b/library/ecp_curves.c
@@ -5643,6 +5643,10 @@
                                   0x01, 0x00, 0x00, 0x00)
     };
 
+    if (X_limbs != 2 * ((192 + biL - 1) / biL)) {
+        return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+    }
+
     return ecp_mod_koblitz(X, X_limbs, Rp, 192);
 }
 
@@ -5673,6 +5677,10 @@
                                   0x01, 0x00, 0x00, 0x00)
     };
 
+    if (X_limbs != 2 * 224 / biL) {
+        return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+    }
+
     return ecp_mod_koblitz(X, X_limbs, Rp, 224);
 }
 
@@ -5702,6 +5710,11 @@
         MBEDTLS_BYTES_TO_T_UINT_8(0xD1, 0x03, 0x00, 0x00,
                                   0x01, 0x00, 0x00, 0x00)
     };
+
+    if (X_limbs != 2 * ((256 + biL - 1) / biL)) {
+        return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+    }
+
     return ecp_mod_koblitz(X, X_limbs, Rp, 256);
 }