Add EC_KEY_priv2buf()

Add new function EC_KEY_priv2buf() to allocated and encode private
key octet in one call. Update and simplify ASN.1 and print routines.

Reviewed-by: Viktor Dukhovni <viktor@openssl.org>

1 files changed, 13 insertions, 38 deletions

diff --git a/crypto/ec/ec_asn1.c b/crypto/ec/ec_asn1.c
index 92bfe06ec5..fe2a979892 100644
--- a/crypto/ec/ec_asn1.c
+++ b/crypto/ec/ec_asn1.c
@@ -1075,8 +1075,9 @@ EC_KEY *d2i_ECPrivateKey(EC_KEY **a, const unsigned char **in, long len)
 int i2d_ECPrivateKey(EC_KEY *a, unsigned char **out)
 {
     int ret = 0, ok = 0;
-    unsigned char *buffer = NULL;
-    size_t buf_len = 0, tmp_len;
+    unsigned char *priv= NULL, *pub= NULL;
+    size_t privlen, publen;
+
     EC_PRIVATEKEY *priv_key = NULL;
 
     if (a == NULL || a->group == NULL ||
@@ -1092,28 +1093,15 @@ int i2d_ECPrivateKey(EC_KEY *a, unsigned char **out)
 
     priv_key->version = a->version;
 
-    buf_len = EC_KEY_priv2oct(a, NULL, 0);
+    privlen = EC_KEY_priv2buf(a, &priv);
 
-    if (buf_len == 0) {
+    if (privlen == 0) {
         ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_EC_LIB);
         goto err;
     }
 
-    buffer = OPENSSL_malloc(buf_len);
-    if (buffer == NULL) {
-        ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_MALLOC_FAILURE);
-        goto err;
-    }
-
-    if (EC_KEY_priv2oct(a, buffer, buf_len) == 0) {
-        ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_EC_LIB);
-        goto err;
-    }
-
-    if (!ASN1_OCTET_STRING_set(priv_key->privateKey, buffer, buf_len)) {
-        ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_ASN1_LIB);
-        goto err;
-    }
+    ASN1_STRING_set0(priv_key->privateKey, priv, privlen);
+    priv = NULL;
 
     if (!(a->enc_flag & EC_PKEY_NO_PARAMETERS)) {
         if ((priv_key->parameters =
@@ -1131,31 +1119,17 @@ int i2d_ECPrivateKey(EC_KEY *a, unsigned char **out)
             goto err;
         }
 
-        tmp_len = EC_POINT_point2oct(a->group, a->pub_key,
-                                     a->conv_form, NULL, 0, NULL);
+        publen = EC_KEY_key2buf(a, a->conv_form, &pub, NULL);
 
-        if (tmp_len > buf_len) {
-            unsigned char *tmp_buffer = OPENSSL_realloc(buffer, tmp_len);
-            if (!tmp_buffer) {
-                ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_MALLOC_FAILURE);
-                goto err;
-            }
-            buffer = tmp_buffer;
-            buf_len = tmp_len;
-        }
-
-        if (!EC_POINT_point2oct(a->group, a->pub_key,
-                                a->conv_form, buffer, buf_len, NULL)) {
+        if (publen == 0) {
             ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_EC_LIB);
             goto err;
         }
 
         priv_key->publicKey->flags &= ~(ASN1_STRING_FLAG_BITS_LEFT | 0x07);
         priv_key->publicKey->flags |= ASN1_STRING_FLAG_BITS_LEFT;
-        if (!ASN1_BIT_STRING_set(priv_key->publicKey, buffer, buf_len)) {
-            ECerr(EC_F_I2D_ECPRIVATEKEY, ERR_R_ASN1_LIB);
-            goto err;
-        }
+        ASN1_STRING_set0(priv_key->publicKey, pub, publen);
+        pub = NULL;
     }
 
     if ((ret = i2d_EC_PRIVATEKEY(priv_key, out)) == 0) {
@@ -1164,7 +1138,8 @@ int i2d_ECPrivateKey(EC_KEY *a, unsigned char **out)
     }
     ok = 1;
  err:
-    OPENSSL_free(buffer);
+    OPENSSL_clear_free(priv, privlen);
+    OPENSSL_free(pub);
     EC_PRIVATEKEY_free(priv_key);
     return (ok ? ret : 0);
 }