Convert ssl3_send_client_key_exchange to CBB.
This relieves some complexity budget for adding Curve25519 to this
code.
This also adds a BN_bn2cbb_padded helper function since this seems to be a
fairly common need.
Change-Id: Ied0066fdaec9d02659abd6eb1a13f33502c9e198
Reviewed-on: https://boringssl-review.googlesource.com/6767
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/include/openssl/bn.h b/include/openssl/bn.h
index bc30d0a..6e971e4 100644
--- a/include/openssl/bn.h
+++ b/include/openssl/bn.h
@@ -253,6 +253,9 @@
* returns 0. Otherwise, it returns 1. */
OPENSSL_EXPORT int BN_bn2bin_padded(uint8_t *out, size_t len, const BIGNUM *in);
+/* BN_bn2cbb_padded behaves like |BN_bn2bin_padded| but writes to a |CBB|. */
+OPENSSL_EXPORT int BN_bn2cbb_padded(CBB *out, size_t len, const BIGNUM *in);
+
/* BN_bn2hex returns an allocated string that contains a NUL-terminated, hex
* representation of |bn|. If |bn| is negative, the first char in the resulting
* string will be '-'. Returns NULL on allocation failure. */