Add output size parameter to signature functions
The functions mbedtls_pk_sign(), mbedtls_pk_sign_restartable(),
mbedtls_ecdsa_write_signature() and mbedtls_ecdsa_write_signature_restartable()
now take an extra parameter indicating the size of the output buffer for the
signature.
No change to RSA because for RSA, the output size is trivial to calculate.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/include/mbedtls/ecdsa.h b/include/mbedtls/ecdsa.h
index 735d377..ecb9df9 100644
--- a/include/mbedtls/ecdsa.h
+++ b/include/mbedtls/ecdsa.h
@@ -294,6 +294,7 @@
* size of the curve used, plus 9. For example, 73 Bytes if
* a 256-bit curve is used. A buffer length of
* #MBEDTLS_ECDSA_MAX_LEN is always safe.
+ * \param sig_size The size of the \p sig buffer in bytes.
* \param slen The address at which to store the actual length of
* the signature written. Must not be \c NULL.
* \param f_rng The RNG function. This must not be \c NULL if
@@ -310,7 +311,7 @@
int mbedtls_ecdsa_write_signature( mbedtls_ecdsa_context *ctx,
mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hlen,
- unsigned char *sig, size_t *slen,
+ unsigned char *sig, size_t sig_size, size_t *slen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng );
@@ -336,6 +337,7 @@
* size of the curve used, plus 9. For example, 73 Bytes if
* a 256-bit curve is used. A buffer length of
* #MBEDTLS_ECDSA_MAX_LEN is always safe.
+ * \param sig_size The size of the \p sig buffer in bytes.
* \param slen The address at which to store the actual length of
* the signature written. Must not be \c NULL.
* \param f_rng The RNG function. This must not be \c NULL if
@@ -356,7 +358,7 @@
int mbedtls_ecdsa_write_signature_restartable( mbedtls_ecdsa_context *ctx,
mbedtls_md_type_t md_alg,
const unsigned char *hash, size_t hlen,
- unsigned char *sig, size_t *slen,
+ unsigned char *sig, size_t sig_size, size_t *slen,
int (*f_rng)(void *, unsigned char *, size_t),
void *p_rng,
mbedtls_ecdsa_restart_ctx *rs_ctx );