From bf88780e64945b568d98591159da2b8604444d73 Mon Sep 17 00:00:00 2001
From: Gilles Peskine <Gilles.Peskine@arm.com>
Date: Fri, 8 Nov 2019 19:21:51 +0100
Subject: [PATCH] Use MBEDTLS_PK_SIGNATURE_MAX_SIZE in X.509

Use the constant that is now provided by the crypto submodule instead
of rolling our own definition which is not correct in all cases.
---
 library/x509write_crt.c | 12 +-----------
 library/x509write_csr.c | 12 +-----------
 2 files changed, 2 insertions(+), 22 deletions(-)

diff --git a/library/x509write_crt.c b/library/x509write_crt.c
index 03fb3fd94..0a2357a58 100644
--- a/library/x509write_crt.c
+++ b/library/x509write_crt.c
@@ -45,16 +45,6 @@
 #include "mbedtls/pem.h"
 #endif /* MBEDTLS_PEM_WRITE_C */
 
-/*
- * For the currently used signature algorithms the buffer to store any signature
- * must be at least of size MAX(MBEDTLS_ECDSA_MAX_LEN, MBEDTLS_MPI_MAX_SIZE)
- */
-#if MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_MPI_MAX_SIZE
-#define SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN
-#else
-#define SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE
-#endif
-
 void mbedtls_x509write_crt_init( mbedtls_x509write_cert *ctx )
 {
     memset( ctx, 0, sizeof( mbedtls_x509write_cert ) );
@@ -347,7 +337,7 @@ int mbedtls_x509write_crt_der( mbedtls_x509write_cert *ctx,
     size_t sig_oid_len = 0;
     unsigned char *c, *c2;
     unsigned char hash[64];
-    unsigned char sig[SIGNATURE_MAX_SIZE];
+    unsigned char sig[MBEDTLS_PK_SIGNATURE_MAX_SIZE];
     size_t sub_len = 0, pub_len = 0, sig_and_oid_len = 0, sig_len;
     size_t len = 0;
     mbedtls_pk_type_t pk_alg;
diff --git a/library/x509write_csr.c b/library/x509write_csr.c
index 0d62d1d48..ffbf436ab 100644
--- a/library/x509write_csr.c
+++ b/library/x509write_csr.c
@@ -49,16 +49,6 @@
 #include "mbedtls/pem.h"
 #endif
 
-/*
- * For the currently used signature algorithms the buffer to store any signature
- * must be at least of size MAX(MBEDTLS_ECDSA_MAX_LEN, MBEDTLS_MPI_MAX_SIZE)
- */
-#if MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_MPI_MAX_SIZE
-#define SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN
-#else
-#define SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE
-#endif
-
 void mbedtls_x509write_csr_init( mbedtls_x509write_csr *ctx )
 {
     memset( ctx, 0, sizeof( mbedtls_x509write_csr ) );
@@ -148,7 +138,7 @@ int mbedtls_x509write_csr_der( mbedtls_x509write_csr *ctx, unsigned char *buf, s
     size_t sig_oid_len = 0;
     unsigned char *c, *c2;
     unsigned char hash[64];
-    unsigned char sig[SIGNATURE_MAX_SIZE];
+    unsigned char sig[MBEDTLS_PK_SIGNATURE_MAX_SIZE];
     unsigned char tmp_buf[2048];
     size_t pub_len = 0, sig_and_oid_len = 0, sig_len;
     size_t len = 0;