Remove X509_get_pubkey_parameters.

It's never called in outside code. This too seems to be a remnant of the DSA
PKIX optional parameter stuff. This is confirmed both by a removed comment and
by the brief documentation at http://www.umich.edu/~x509/ssleay/x509_pkey.html

RFC 5480 does not allow ECDSA keys to be missing parameters, so this logic is
incorrect for ECDSA anyway.  It was also failing to check
EVP_PKEY_copy_parameters' return value. And that logic looks pretty suspect if
you have a chain made up multiple certificate types.

Change-Id: Id6c60659a0162356c7f3eae5c797047366baae1c
Reviewed-on: https://boringssl-review.googlesource.com/3485
Reviewed-by: Adam Langley <agl@google.com>

crypto/x509/x509_vfy.c

diff --git a/crypto/x509/x509_vfy.c b/crypto/x509/x509_vfy.c
index 28d2182..78e70a6 100644
--- a/crypto/x509/x509_vfy.c
+++ b/crypto/x509/x509_vfy.c
@@ -410,9 +410,6 @@
 
 	if (!ok) goto end;
 
-	/* We may as well copy down any DSA parameters that are required */
-	X509_get_pubkey_parameters(NULL,ctx->chain);
-
 	/* Check revocation status: we do this after copying parameters
 	 * because they may be needed for CRL signature verification.
 	 */
@@ -441,12 +438,8 @@
 	/* If we get this far evaluate policies */
 	if (!bad_chain && (ctx->param->flags & X509_V_FLAG_POLICY_CHECK))
 		ok = ctx->check_policy(ctx);
-	if(!ok) goto end;
-	if (0)
-		{
+
 end:
-		X509_get_pubkey_parameters(NULL,ctx->chain);
-		}
 	if (sktmp != NULL) sk_X509_free(sktmp);
 	if (chain_ss != NULL) X509_free(chain_ss);
 	return ok;
@@ -1932,48 +1925,6 @@
 	return ASN1_TIME_adj(s, t, offset_day, offset_sec);
 	}
 
-int X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
-	{
-	EVP_PKEY *ktmp=NULL,*ktmp2;
-	size_t i,j;
-
-	if ((pkey != NULL) && !EVP_PKEY_missing_parameters(pkey)) return 1;
-
-	for (i=0; i<sk_X509_num(chain); i++)
-		{
-		ktmp=X509_get_pubkey(sk_X509_value(chain,i));
-		if (ktmp == NULL)
-			{
-			OPENSSL_PUT_ERROR(X509, X509_get_pubkey_parameters, X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
-			return 0;
-			}
-		if (!EVP_PKEY_missing_parameters(ktmp))
-			break;
-		else
-			{
-			EVP_PKEY_free(ktmp);
-			ktmp=NULL;
-			}
-		}
-	if (ktmp == NULL)
-		{
-		OPENSSL_PUT_ERROR(X509, X509_get_pubkey_parameters, X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
-		return 0;
-		}
-
-	/* first, populate the other certs */
-	for (j=i-1; j < i; j--)
-		{
-		ktmp2=X509_get_pubkey(sk_X509_value(chain,j));
-		EVP_PKEY_copy_parameters(ktmp2,ktmp);
-		EVP_PKEY_free(ktmp2);
-		}
-	
-	if (pkey != NULL) EVP_PKEY_copy_parameters(pkey,ktmp);
-	EVP_PKEY_free(ktmp);
-	return 1;
-	}
-
 /* Make a delta CRL as the diff between two full CRLs */
 
 X509_CRL *X509_CRL_diff(X509_CRL *base, X509_CRL *newer,

include/openssl/x509.h

diff --git a/include/openssl/x509.h b/include/openssl/x509.h
index f500876..acdab6e 100644
--- a/include/openssl/x509.h
+++ b/include/openssl/x509.h
@@ -748,8 +748,6 @@
 
 OPENSSL_EXPORT int		X509_PUBKEY_set(X509_PUBKEY **x, EVP_PKEY *pkey);
 OPENSSL_EXPORT EVP_PKEY *	X509_PUBKEY_get(X509_PUBKEY *key);
-OPENSSL_EXPORT int		X509_get_pubkey_parameters(EVP_PKEY *pkey,
-					   STACK_OF(X509) *chain);
 OPENSSL_EXPORT int		i2d_PUBKEY(const EVP_PKEY *a,unsigned char **pp);
 OPENSSL_EXPORT EVP_PKEY *	d2i_PUBKEY(EVP_PKEY **a,const unsigned char **pp,
 			long length);