commit bd42603943c76ee127fd0e3c7872b60de806f214
author David Benjamin <davidben@chromium.org> Sun Jan 03 00:57:37 2016 -0800
committer Adam Langley <agl@google.com> Tue Feb 16 19:40:53 2016 +0000
tree ae14f71ac2bc836b3e95a756dba35017085ba070
parent 375124b1622e112fbd4584e806030eb7476904c5

Add a convenience function for i2d compatibility wrappers.

An i2d compatibility function is rather long, so add CBB_finish_i2d for
part of it. It takes a CBB as input so only a 'marshal' function is
needed, rather than a 'to_bytes' one.

Also replace the *inp d2i update pattern with a slightly shorter one.

Change-Id: Ibb41059c9532f6a8ce33460890cc1afe26adc97c
Reviewed-on: https://boringssl-review.googlesource.com/6868
Reviewed-by: Adam Langley <agl@google.com>

crypto/ecdsa/ecdsa_asn1.c

diff --git a/crypto/ecdsa/ecdsa_asn1.c b/crypto/ecdsa/ecdsa_asn1.c
index 61f5d62..3a47257 100644
--- a/crypto/ecdsa/ecdsa_asn1.c
+++ b/crypto/ecdsa/ecdsa_asn1.c
@@ -61,6 +61,7 @@
 #include <openssl/ec_key.h>
 #include <openssl/mem.h>
 
+#include "../bytestring/internal.h"
 #include "../ec/internal.h"
 
 
@@ -211,30 +212,15 @@
     ECDSA_SIG_free(*out);
     *out = ret;
   }
-  *inp += (size_t)len - CBS_len(&cbs);
+  *inp = CBS_data(&cbs);
   return ret;
 }
 
 int i2d_ECDSA_SIG(const ECDSA_SIG *sig, uint8_t **outp) {
-  uint8_t *der;
-  size_t der_len;
-  if (!ECDSA_SIG_to_bytes(&der, &der_len, sig)) {
+  CBB cbb;
+  if (!CBB_init(&cbb, 0) ||
+      !ECDSA_SIG_marshal(&cbb, sig)) {
     return -1;
   }
-  if (der_len > INT_MAX) {
-    OPENSSL_PUT_ERROR(ECDSA, ERR_R_OVERFLOW);
-    OPENSSL_free(der);
-    return -1;
-  }
-  if (outp != NULL) {
-    if (*outp == NULL) {
-      *outp = der;
-      der = NULL;
-    } else {
-      memcpy(*outp, der, der_len);
-      *outp += der_len;
-    }
-  }
-  OPENSSL_free(der);
-  return (int)der_len;
+  return CBB_finish_i2d(&cbb, outp);
 }