[PATCH 03 of 11] SSL: updated comment about session sizes

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1661481948 -10800
#      Fri Aug 26 05:45:48 2022 +0300
# Node ID 86d827338fdd13ea899d618b0bcb2be23469cbac
# Parent  5b137f110e84af974ef2b9efcf35bec2d883c187
SSL: updated comment about session sizes.

Previous numbers are somewhat outdated, typical ASN1 representations of
sessions are slightly bigger now.

diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -3785,16 +3785,16 @@ ngx_ssl_session_cache_init(ngx_shm_zone_
 
 /*
  * The length of the session id is 16 bytes for SSLv2 sessions and
- * between 1 and 32 bytes for SSLv3/TLSv1, typically 32 bytes.
- * It seems that the typical length of the external ASN1 representation
- * of a session is 118 or 119 bytes for SSLv3/TSLv1.
+ * between 1 and 32 bytes for SSLv3 and TLS, typically 32 bytes.
+ * Typical length of the external ASN1 representation of a session
+ * is about 150 bytes plus SNI server name.
  *
- * Thus on 32-bit platforms we allocate separately an rbtree node,
+ * On 32-bit platforms we allocate separately an rbtree node,
  * a session id, and an ASN1 representation, they take accordingly
- * 64, 32, and 128 bytes.
+ * 64, 32, and 256 bytes.
  *
  * On 64-bit platforms we allocate separately an rbtree node + session_id,
- * and an ASN1 representation, they take accordingly 128 and 128 bytes.
+ * and an ASN1 representation, they take accordingly 128 and 256 bytes.
  *
  * OpenSSL's i2d_SSL_SESSION() and d2i_SSL_SESSION are slow,
  * so they are outside the code locked by shared pool mutex