Unexport SSL_SESSION_ASN1_VERSION.

It's pretty clearly pointless to put in the public header.

Change-Id: I9527aba09b618f957618e653c4f2ae379ddd0fdb
Reviewed-on: https://boringssl-review.googlesource.com/6293
Reviewed-by: Adam Langley <alangley@gmail.com>
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index e533f96..e23615b 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -2591,11 +2591,6 @@
  *
  * Functions below here haven't been touched up and may be underdocumented. */
 
-/* SSLeay version number for ASN.1 encoding of the session information */
-/* Version 0 - initial version
- * Version 1 - added the optional peer certificate. */
-#define SSL_SESSION_ASN1_VERSION 0x0001
-
 #define SSL_MAX_SSL_SESSION_ID_LENGTH 32
 #define SSL_MAX_SID_CTX_LENGTH 32
 #define SSL_MAX_MASTER_KEY_LENGTH 48
diff --git a/ssl/ssl_asn1.c b/ssl/ssl_asn1.c
index 0d4760d..9e61fb6 100644
--- a/ssl/ssl_asn1.c
+++ b/ssl/ssl_asn1.c
@@ -130,13 +130,15 @@
  *     compressionMethod       [11] OCTET STRING OPTIONAL,
  *     srpUsername             [12] OCTET STRING OPTIONAL, */
 
+static const int kVersion = 1;
+
 static const int kTimeTag =
     CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 1;
 static const int kTimeoutTag =
     CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 2;
 static const int kPeerTag =
     CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 3;
- static const int kSessionIDContextTag =
+static const int kSessionIDContextTag =
     CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 4;
 static const int kVerifyResultTag =
     CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC | 5;
@@ -190,7 +192,7 @@
   CBB_zero(&cbb);
   if (!CBB_init(&cbb, 0) ||
       !CBB_add_asn1(&cbb, &session, CBS_ASN1_SEQUENCE) ||
-      !CBB_add_asn1_uint64(&session, SSL_SESSION_ASN1_VERSION) ||
+      !CBB_add_asn1_uint64(&session, kVersion) ||
       !CBB_add_asn1_uint64(&session, in->ssl_version) ||
       !CBB_add_asn1(&session, &child, CBS_ASN1_OCTETSTRING) ||
       !CBB_add_u16(&child, (uint16_t)(in->cipher->id & 0xffff)) ||
@@ -509,7 +511,7 @@
   uint64_t version, ssl_version;
   if (!CBS_get_asn1(cbs, &session, CBS_ASN1_SEQUENCE) ||
       !CBS_get_asn1_uint64(&session, &version) ||
-      version != SSL_SESSION_ASN1_VERSION ||
+      version != kVersion ||
       !CBS_get_asn1_uint64(&session, &ssl_version)) {
     OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_SSL_SESSION);
     goto err;