Unexport and rename hex_to_string, string_to_hex, and name_cmp.

Squatting these names is rather rude. Also hex_to_string and
string_to_hex do the opposite of what one would expect, so rename them
to something a bit less confusing.

Update-Note: This removes some random utility functions. name_cmp is
very specific to OpenSSL's config file format, so it's unlikely anyone
is relying on it. I removed the one use of hex_to_string and
string_to_hex I could find.

Change-Id: I01554885ad306251e6982100d0b15cd89b1cdea7
Reviewed-on: https://boringssl-review.googlesource.com/c/33364
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>

crypto/x509v3/v3_alt.c

diff --git a/crypto/x509v3/v3_alt.c b/crypto/x509v3/v3_alt.c
index b78a410..5a4fadf 100644
--- a/crypto/x509v3/v3_alt.c
+++ b/crypto/x509v3/v3_alt.c
@@ -64,6 +64,9 @@
 #include <openssl/obj.h>
 #include <openssl/x509v3.h>
 
+#include "internal.h"
+
+
 static GENERAL_NAMES *v2i_subject_alt(X509V3_EXT_METHOD *method,
                                       X509V3_CTX *ctx,
                                       STACK_OF(CONF_VALUE) *nval);
@@ -261,7 +264,7 @@
     }
     for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
         cnf = sk_CONF_VALUE_value(nval, i);
-        if (!name_cmp(cnf->name, "issuer") && cnf->value &&
+        if (!x509v3_name_cmp(cnf->name, "issuer") && cnf->value &&
             !strcmp(cnf->value, "copy")) {
             if (!copy_issuer(ctx, gens))
                 goto err;
@@ -331,11 +334,11 @@
     }
     for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
         cnf = sk_CONF_VALUE_value(nval, i);
-        if (!name_cmp(cnf->name, "email") && cnf->value &&
+        if (!x509v3_name_cmp(cnf->name, "email") && cnf->value &&
             !strcmp(cnf->value, "copy")) {
             if (!copy_email(ctx, gens, 0))
                 goto err;
-        } else if (!name_cmp(cnf->name, "email") && cnf->value &&
+        } else if (!x509v3_name_cmp(cnf->name, "email") && cnf->value &&
                    !strcmp(cnf->value, "move")) {
             if (!copy_email(ctx, gens, 1))
                 goto err;
@@ -545,19 +548,19 @@
         return NULL;
     }
 
-    if (!name_cmp(name, "email"))
+    if (!x509v3_name_cmp(name, "email"))
         type = GEN_EMAIL;
-    else if (!name_cmp(name, "URI"))
+    else if (!x509v3_name_cmp(name, "URI"))
         type = GEN_URI;
-    else if (!name_cmp(name, "DNS"))
+    else if (!x509v3_name_cmp(name, "DNS"))
         type = GEN_DNS;
-    else if (!name_cmp(name, "RID"))
+    else if (!x509v3_name_cmp(name, "RID"))
         type = GEN_RID;
-    else if (!name_cmp(name, "IP"))
+    else if (!x509v3_name_cmp(name, "IP"))
         type = GEN_IPADD;
-    else if (!name_cmp(name, "dirName"))
+    else if (!x509v3_name_cmp(name, "dirName"))
         type = GEN_DIRNAME;
-    else if (!name_cmp(name, "otherName"))
+    else if (!x509v3_name_cmp(name, "otherName"))
         type = GEN_OTHERNAME;
     else {
         OPENSSL_PUT_ERROR(X509V3, X509V3_R_UNSUPPORTED_OPTION);