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/* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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* _ __ ___ ___ __| | ___ ___| | mod_ssl
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* | '_ ` _ \ / _ \ / _` | / __/ __| | Apache Interface to OpenSSL
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* | | | | | | (_) | (_| | \__ \__ \ |
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* |_| |_| |_|\___/ \__,_|___|___/___/_|
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* Session Cache via Shared Memory (Cyclic Buffer Variant)
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#include "ssl_private.h"
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* This shared memory based SSL session cache implementation was
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* originally written by Geoff Thorpe <geoff geoffthorpe.net> for C2Net
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* Europe as a contribution to Ralf Engelschall's mod_ssl project.
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* The shared-memory segment header can be cast to and from the
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* SHMCBHeader type, all other structures need to be initialised by
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* The "header" looks like this;
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* data applying to the overall structure:
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* - division_offset (unsigned int):
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* how far into the shared memory segment the first division is.
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* - division_size (unsigned int):
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* how many bytes each division occupies.
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* (NB: This includes the queue and the cache)
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* - division_mask (unsigned char):
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* the "mask" in the next line. Add one to this,
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* and that's the number of divisions.
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* data applying to within each division:
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* - queue_size (unsigned int):
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* how big each "queue" is. NB: The queue is the first block in each
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* division and is followed immediately by the cache itself so so
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* there's no cache_offset value.
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* data applying to within each queue:
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* - index_num (unsigned char):
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* how many indexes in each cache's queue
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* - index_offset (unsigned char):
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* how far into the queue the first index is.
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* how big each index is.
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* data applying to within each cache:
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* - cache_data_offset (unsigned int):
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* how far into the cache the session-data array is stored.
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* - cache_data_size (unsigned int):
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* how big each cache's data block is.
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* statistics data (this will eventually be per-division but right now
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* there's only one mutex):
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* - stores (unsigned long):
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* how many stores have been performed in the cache.
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* - expiries (unsigned long):
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* how many session have been expired from the cache.
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* - scrolled (unsigned long):
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* how many sessions have been scrolled out of full cache during a
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* "store" operation. This is different to the "removes" stats as
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* they are requested by mod_ssl/Apache, these are done because of
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* cache logistics. (NB: Also, this value should be deducible from
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* the others if my code has no bugs, but I count it anyway - plus
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* it helps debugging :-).
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* - retrieves_hit (unsigned long):
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* how many session-retrieves have succeeded.
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* - retrieves_miss (unsigned long):
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* how many session-retrieves have failed.
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* - removes_hit (unsigned long):
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* - removes_miss (unsigned long):
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* Following immediately after the header is an array of "divisions".
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* Each division is simply a "queue" immediately followed by its
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* corresponding "cache". Each division handles some pre-defined band
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* of sessions by using the "division_mask" in the header. Eg. if
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* division_mask=0x1f then there are 32 divisions, the first of which
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* will store sessions whose least-significant 5 bits are 0, the second
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* stores session whose LS 5 bits equal 1, etc. A queue is an indexing
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* structure referring to its corresponding cache.
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* A "queue" looks like this;
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* - first_pos (unsigned int):
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* the location within the array of indexes where the virtual
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* "left-hand-edge" of the cyclic buffer is.
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* - pos_count (unsigned int):
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* the number of indexes occupied from first_pos onwards.
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* ...followed by an array of indexes, each of which can be
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* memcpy'd to and from an SHMCBIndex, and look like this;
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* - expires (time_t):
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* the time() value at which this session expires.
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* - offset (unsigned int):
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* the offset within the cache data block where the corresponding
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* - s_id2 (unsigned char):
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* the second byte of the session_id, stored as an optimisation to
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* reduce the number of d2i_SSL_SESSION calls that are made when doing
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* - removed (unsigned char):
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* a byte used to indicate whether a session has been "passively"
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* removed. Ie. it is still in the cache but is to be disregarded by
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* any "retrieve" operation.
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* A "cache" looks like this;
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* - first_pos (unsigned int):
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* the location within the data block where the virtual
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* "left-hand-edge" of the cyclic buffer is.
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* - pos_count (unsigned int):
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* the number of bytes used in the data block from first_pos onwards.
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* ...followed by the data block in which actual DER-encoded SSL
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* sessions are stored.
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* Header - can be memcpy'd to and from the front of the shared
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* memory segment. NB: The first copy (commented out) has the
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* elements in a meaningful order, but due to data-alignment
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* braindeadness, the second (uncommented) copy has the types grouped
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* so as to decrease "struct-bloat". sigh.
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unsigned long num_stores;
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unsigned long num_expiries;
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unsigned long num_scrolled;
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unsigned long num_retrieves_hit;
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unsigned long num_retrieves_miss;
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unsigned long num_removes_hit;
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unsigned long num_removes_miss;
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unsigned int division_offset;
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unsigned int division_size;
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unsigned int queue_size;
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unsigned int cache_data_offset;
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unsigned int cache_data_size;
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unsigned char division_mask;
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unsigned int index_num;
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unsigned int index_offset;
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unsigned int index_size;
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* Index - can be memcpy'd to and from an index inside each
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* queue's index array.
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unsigned char removed;
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* Queue - must be populated by a call to shmcb_get_division
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* and the structure's pointers are used for updating (ie.
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* the structure doesn't need any "set" to update values).
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unsigned int *first_pos;
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unsigned int *pos_count;
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* Cache - same comment as for Queue. 'Queue's are in a 1-1
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* correspondance with 'Cache's and are usually carried round
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* in a pair, they are only seperated for clarity.
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unsigned int *first_pos;
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unsigned int *pos_count;
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* Forward function prototypes.
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/* Functions for working around data-alignment-picky systems (sparcs,
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Irix, etc). These use "memcpy" as a way of foxing these systems into
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treating the composite types as byte-arrays rather than higher-level
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primitives that it prefers to have 4-(or 8-)byte aligned. I don't
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envisage this being a performance issue as a couple of 2 or 4 byte
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memcpys can hardly make a dent on the massive memmove operations this
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cache technique avoids, nor the overheads of ASN en/decoding. */
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static unsigned int shmcb_get_safe_uint(unsigned int *);
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static void shmcb_set_safe_uint_ex(unsigned char *, const unsigned char *);
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#define shmcb_set_safe_uint(pdest, src) \
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unsigned int tmp_uint = src; \
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shmcb_set_safe_uint_ex((unsigned char *)pdest, \
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(const unsigned char *)(&tmp_uint)); \
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#if 0 /* Unused so far */
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static unsigned long shmcb_get_safe_ulong(unsigned long *);
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static void shmcb_set_safe_ulong_ex(unsigned char *, const unsigned char *);
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#define shmcb_set_safe_ulong(pdest, src) \
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unsigned long tmp_ulong = src; \
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shmcb_set_safe_ulong_ex((unsigned char *)pdest, \
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(const unsigned char *)(&tmp_ulong)); \
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static time_t shmcb_get_safe_time(time_t *);
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static void shmcb_set_safe_time_ex(unsigned char *, const unsigned char *);
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#define shmcb_set_safe_time(pdest, src) \
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time_t tmp_time = src; \
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shmcb_set_safe_time_ex((unsigned char *)pdest, \
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(const unsigned char *)(&tmp_time)); \
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/* This is used to persuade the compiler from using an inline memset()
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* which has no respect for alignment, since the size parameter is
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* often a compile-time constant. GCC >= 4 will aggressively inline
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* static functions, so it's marked as explicitly not-inline. */
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#if defined(__GNUC__) && __GNUC__ > 3
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__attribute__((__noinline__))
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static void shmcb_safe_clear(void *ptr, size_t size)
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memset(ptr, 0, size);
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/* Underlying functions for session-caching */
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static BOOL shmcb_init_memory(server_rec *, void *, unsigned int);
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static BOOL shmcb_store_session(server_rec *, void *, UCHAR *, int, SSL_SESSION *, time_t);
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static SSL_SESSION *shmcb_retrieve_session(server_rec *, void *, UCHAR *, int);
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static BOOL shmcb_remove_session(server_rec *, void *, UCHAR *, int);
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/* Utility functions for manipulating the structures */
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static void shmcb_get_header(void *, SHMCBHeader **);
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static BOOL shmcb_get_division(SHMCBHeader *, SHMCBQueue *, SHMCBCache *, unsigned int);
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static SHMCBIndex *shmcb_get_index(const SHMCBQueue *, unsigned int);
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static unsigned int shmcb_expire_division(server_rec *, SHMCBQueue *, SHMCBCache *);
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static BOOL shmcb_insert_encoded_session(server_rec *, SHMCBQueue *, SHMCBCache *, unsigned char *, unsigned int, unsigned char *, time_t);
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static SSL_SESSION *shmcb_lookup_session_id(server_rec *, SHMCBQueue *, SHMCBCache *, UCHAR *, unsigned int);
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static BOOL shmcb_remove_session_id(server_rec *, SHMCBQueue *, SHMCBCache *, UCHAR *, unsigned int);
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* Data-alignment functions (a.k.a. avoidance tactics)
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* NB: On HPUX (and possibly others) there is a *very* mischievous little
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* "optimisation" in the compilers where it will convert the following;
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* memcpy(dest_ptr, &source, sizeof(unsigned int));
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* (where dest_ptr is of type (unsigned int *) and source is (unsigned int))
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* *dest_ptr = source; (or *dest_ptr = *(&source), not sure).
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* Either way, it completely destroys the whole point of these _safe_
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* functions, because the assignment operation will fall victim to the
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* architecture's byte-alignment dictations, whereas the memcpy (as a
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* byte-by-byte copy) should not. sigh. So, if you're wondering about the
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* apparently unnecessary conversions to (unsigned char *) in these
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* functions, you now have an explanation. Don't just revert them back and
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* say "ooh look, it still works" - if you try it on HPUX (well, 32-bit
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* HPUX 11.00 at least) you may find it fails with a SIGBUS. :-(
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static unsigned int shmcb_get_safe_uint(unsigned int *ptr)
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shmcb_set_safe_uint_ex((unsigned char *)(&ret),
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(const unsigned char *)ptr);
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static void shmcb_set_safe_uint_ex(unsigned char *dest,
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const unsigned char *src)
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memcpy(dest, src, sizeof(unsigned int));
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#if 0 /* Unused so far */
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static unsigned long shmcb_get_safe_ulong(unsigned long *ptr)
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shmcb_set_safe_ulong_ex((unsigned char *)(&ret),
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(const unsigned char *)ptr);
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static void shmcb_set_safe_ulong_ex(unsigned char *dest,
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const unsigned char *src)
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memcpy(dest, src, sizeof(unsigned long));
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static time_t shmcb_get_safe_time(time_t * ptr)
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shmcb_set_safe_time_ex((unsigned char *)(&ret),
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(const unsigned char *)ptr);
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static void shmcb_set_safe_time_ex(unsigned char *dest,
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const unsigned char *src)
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memcpy(dest, src, sizeof(time_t));
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** High-Level "handlers" as per ssl_scache.c
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void ssl_scache_shmcb_init(server_rec *s, apr_pool_t *p)
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SSLModConfigRec *mc = myModConfig(s);
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apr_size_t shm_segsize;
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* Create shared memory segment
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if (mc->szSessionCacheDataFile == NULL) {
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ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
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"SSLSessionCache required");
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/* Use anonymous shm by default, fall back on name-based. */
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rv = apr_shm_create(&(mc->pSessionCacheDataMM),
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mc->nSessionCacheDataSize,
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if (APR_STATUS_IS_ENOTIMPL(rv)) {
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/* For a name-based segment, remove it first in case of a
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* previous unclean shutdown. */
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apr_shm_remove(mc->szSessionCacheDataFile, mc->pPool);
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rv = apr_shm_create(&(mc->pSessionCacheDataMM),
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mc->nSessionCacheDataSize,
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mc->szSessionCacheDataFile,
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if (rv != APR_SUCCESS) {
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ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
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"Cannot allocate shared memory: (%d)%s", rv,
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apr_strerror(rv, buf, sizeof(buf)));
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shm_segment = apr_shm_baseaddr_get(mc->pSessionCacheDataMM);
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shm_segsize = apr_shm_size_get(mc->pSessionCacheDataMM);
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"shmcb_init allocated %" APR_SIZE_T_FMT
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" bytes of shared memory",
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if (!shmcb_init_memory(s, shm_segment, shm_segsize)) {
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ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
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"Failure initialising 'shmcb' shared memory");
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ap_log_error(APLOG_MARK, APLOG_INFO, 0, s,
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"Shared memory session cache initialised");
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mc->tSessionCacheDataTable = shm_segment;
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void ssl_scache_shmcb_kill(server_rec *s)
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SSLModConfigRec *mc = myModConfig(s);
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if (mc->pSessionCacheDataMM != NULL) {
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apr_shm_destroy(mc->pSessionCacheDataMM);
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mc->pSessionCacheDataMM = NULL;
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BOOL ssl_scache_shmcb_store(server_rec *s, UCHAR *id, int idlen,
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time_t timeout, SSL_SESSION * pSession)
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SSLModConfigRec *mc = myModConfig(s);
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BOOL to_return = FALSE;
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if (!shmcb_store_session(s, mc->tSessionCacheDataTable, id, idlen,
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/* in this cache engine, "stores" should never fail. */
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ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
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"'shmcb' code was unable to store a "
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"session in the cache.");
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"shmcb_store successful");
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SSL_SESSION *ssl_scache_shmcb_retrieve(server_rec *s, UCHAR *id, int idlen)
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SSLModConfigRec *mc = myModConfig(s);
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SSL_SESSION *pSession;
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pSession = shmcb_retrieve_session(s, mc->tSessionCacheDataTable, id, idlen);
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"shmcb_retrieve had a hit");
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"shmcb_retrieve had a miss");
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ap_log_error(APLOG_MARK, APLOG_INFO, 0, s,
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"Client requested a 'session-resume' but "
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"we have no such session.");
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void ssl_scache_shmcb_remove(server_rec *s, UCHAR *id, int idlen)
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SSLModConfigRec *mc = myModConfig(s);
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shmcb_remove_session(s, mc->tSessionCacheDataTable, id, idlen);
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void ssl_scache_shmcb_status(request_rec *r, int flags, apr_pool_t *p)
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SSLModConfigRec *mc = myModConfig(r->server);
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unsigned int loop, total, cache_total, non_empty_divisions;
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int index_pct, cache_pct;
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time_t average_expiry, now, max_expiry, min_expiry, idxexpiry;
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ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "inside shmcb_status");
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/* Get the header structure. */
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shmcb_get_header(mc->tSessionCacheDataTable, &header);
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total = cache_total = non_empty_divisions = 0;
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average_expiry = max_expiry = min_expiry = 0;
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/* It may seem strange to grab "now" at this point, but in theory
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* we should never have a negative threshold but grabbing "now" after
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* the loop (which performs expiries) could allow that chance. */
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for (loop = 0; loop <= header->division_mask; loop++) {
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if (shmcb_get_division(header, &queue, &cache, loop)) {
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shmcb_expire_division(r->server, &queue, &cache);
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total += shmcb_get_safe_uint(queue.pos_count);
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cache_total += shmcb_get_safe_uint(cache.pos_count);
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if (shmcb_get_safe_uint(queue.pos_count) > 0) {
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idx = shmcb_get_index(&queue,
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shmcb_get_safe_uint(queue.first_pos));
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non_empty_divisions++;
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idxexpiry = shmcb_get_safe_time(&(idx->expires));
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expiry_total += (double) idxexpiry;
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max_expiry = (idxexpiry > max_expiry ? idxexpiry :
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min_expiry = idxexpiry;
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min_expiry = (idxexpiry < min_expiry ? idxexpiry :
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index_pct = (100 * total) / (header->index_num * (header->division_mask + 1));
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cache_pct = (100 * cache_total) / (header->cache_data_size * (header->division_mask + 1));
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ap_rprintf(r, "cache type: <b>SHMCB</b>, shared memory: <b>%d</b> "
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"bytes, current sessions: <b>%d</b><br>",
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mc->nSessionCacheDataSize, total);
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ap_rprintf(r, "sub-caches: <b>%d</b>, indexes per sub-cache: "
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"<b>%d</b><br>", (int) header->division_mask + 1,
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(int) header->index_num);
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if (non_empty_divisions != 0) {
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average_expiry = (time_t)(expiry_total / (double)non_empty_divisions);
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ap_rprintf(r, "time left on oldest entries' SSL sessions: ");
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if (now < average_expiry)
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ap_rprintf(r, "avg: <b>%d</b> seconds, (range: %d...%d)<br>",
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(int)(average_expiry - now), (int) (min_expiry - now),
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(int)(max_expiry - now));
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ap_rprintf(r, "expiry threshold: <b>Calculation Error!</b>"
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ap_rprintf(r, "index usage: <b>%d%%</b>, cache usage: <b>%d%%</b>"
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"<br>", index_pct, cache_pct);
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ap_rprintf(r, "total sessions stored since starting: <b>%lu</b><br>",
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ap_rprintf(r, "total sessions expired since starting: <b>%lu</b><br>",
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header->num_expiries);
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ap_rprintf(r, "total (pre-expiry) sessions scrolled out of the "
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"cache: <b>%lu</b><br>", header->num_scrolled);
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ap_rprintf(r, "total retrieves since starting: <b>%lu</b> hit, "
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"<b>%lu</b> miss<br>", header->num_retrieves_hit,
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header->num_retrieves_miss);
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ap_rprintf(r, "total removes since starting: <b>%lu</b> hit, "
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"<b>%lu</b> miss<br>", header->num_removes_hit,
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header->num_removes_miss);
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ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "leaving shmcb_status");
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** Memory manipulation and low-level cache operations
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static BOOL shmcb_init_memory(
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server_rec *s, void *shm_mem,
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unsigned int shm_mem_size)
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unsigned int temp, loop, granularity;
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ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"entered shmcb_init_memory()");
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/* Calculate some sizes... */
558
temp = sizeof(SHMCBHeader);
560
/* If the segment is ridiculously too small, bail out */
561
if (shm_mem_size < (2*temp)) {
562
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
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"shared memory segment too small");
567
/* Make temp the amount of memory without the header */
568
temp = shm_mem_size - temp;
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/* Work on the basis that you need 10 bytes index for each session
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* (approx 150 bytes), which is to divide temp by 160 - and then
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* make sure we err on having too index space to burn even when
573
* the cache is full, which is a lot less stupid than having
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* having not enough index space to utilise the whole cache!. */
576
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
577
"for %u bytes, recommending %u indexes",
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/* We should divide these indexes evenly amongst the queues. Try
581
* to get it so that there are roughly half the number of divisions
582
* as there are indexes in each division. */
584
while ((temp / granularity) < (2 * granularity))
587
/* So we have 'granularity' divisions, set 'temp' equal to the
588
* number of indexes in each division. */
591
/* Too small? Bail ... */
593
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
594
"shared memory segment too small");
598
/* OK, we're sorted - from here on in, the return should be TRUE */
599
header = (SHMCBHeader *)shm_mem;
600
header->division_mask = (unsigned char)(granularity - 1);
601
header->division_offset = sizeof(SHMCBHeader);
602
header->index_num = temp;
603
header->index_offset = (2 * sizeof(unsigned int));
604
header->index_size = sizeof(SHMCBIndex);
605
header->queue_size = header->index_offset +
606
(header->index_num * header->index_size);
608
/* Now calculate the space for each division */
609
temp = shm_mem_size - header->division_offset;
610
header->division_size = temp / granularity;
612
/* Calculate the space left in each division for the cache */
613
temp -= header->queue_size;
614
header->cache_data_offset = (2 * sizeof(unsigned int));
615
header->cache_data_size = header->division_size -
616
header->queue_size - header->cache_data_offset;
618
/* Output trace info */
619
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
620
"shmcb_init_memory choices follow");
621
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
622
"division_mask = 0x%02X", header->division_mask);
623
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
624
"division_offset = %u", header->division_offset);
625
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
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"division_size = %u", header->division_size);
627
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
628
"queue_size = %u", header->queue_size);
629
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
630
"index_num = %u", header->index_num);
631
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
632
"index_offset = %u", header->index_offset);
633
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
634
"index_size = %u", header->index_size);
635
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
636
"cache_data_offset = %u", header->cache_data_offset);
637
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
638
"cache_data_size = %u", header->cache_data_size);
640
/* The header is done, make the caches empty */
641
for (loop = 0; loop < granularity; loop++) {
642
if (!shmcb_get_division(header, &queue, &cache, loop))
643
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s, "shmcb_init_memory, " "internal error");
644
shmcb_set_safe_uint(cache.first_pos, 0);
645
shmcb_set_safe_uint(cache.pos_count, 0);
646
shmcb_set_safe_uint(queue.first_pos, 0);
647
shmcb_set_safe_uint(queue.pos_count, 0);
650
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
651
"leaving shmcb_init_memory()");
655
static BOOL shmcb_store_session(
656
server_rec *s, void *shm_segment, UCHAR *id,
657
int idlen, SSL_SESSION * pSession,
663
unsigned char masked_index;
664
unsigned char encoded[SSL_SESSION_MAX_DER];
665
unsigned char *ptr_encoded;
666
unsigned int len_encoded;
668
unsigned char *session_id = SSL_SESSION_get_session_id(pSession);
670
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
671
"inside shmcb_store_session");
673
/* Get the header structure, which division this session will fall into etc. */
674
shmcb_get_header(shm_segment, &header);
675
masked_index = session_id[0] & header->division_mask;
676
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
677
"session_id[0]=%u, masked index=%u",
678
session_id[0], masked_index);
679
if (!shmcb_get_division(header, &queue, &cache, (unsigned int)masked_index)) {
680
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
681
"shmcb_store_session internal error");
685
/* Serialise the session, work out how much we're dealing
686
* with. NB: This check could be removed if we're not paranoid
687
* or we find some assurance that it will never be necessary. */
688
len_encoded = i2d_SSL_SESSION(pSession, NULL);
689
if (len_encoded > SSL_SESSION_MAX_DER) {
690
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
691
"session is too big (%u bytes)", len_encoded);
694
ptr_encoded = encoded;
695
len_encoded = i2d_SSL_SESSION(pSession, &ptr_encoded);
696
expiry_time = timeout;
697
if (!shmcb_insert_encoded_session(s, &queue, &cache, encoded,
698
len_encoded, session_id,
700
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
701
"can't store a session!");
704
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
705
"leaving shmcb_store successfully");
706
header->num_stores++;
710
static SSL_SESSION *shmcb_retrieve_session(
711
server_rec *s, void *shm_segment,
712
UCHAR *id, int idlen)
717
unsigned char masked_index;
718
SSL_SESSION *pSession;
720
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
721
"inside shmcb_retrieve_session");
723
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s, "unusably short session_id provided "
724
"(%u bytes)", idlen);
728
/* Get the header structure, which division this session lookup
729
* will come from etc. */
730
shmcb_get_header(shm_segment, &header);
731
masked_index = id[0] & header->division_mask;
732
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
733
"id[0]=%u, masked index=%u", id[0], masked_index);
734
if (!shmcb_get_division(header, &queue, &cache, (unsigned int) masked_index)) {
735
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
736
"shmcb_retrieve_session internal error");
737
header->num_retrieves_miss++;
741
/* Get the session corresponding to the session_id or NULL if it
742
* doesn't exist (or is flagged as "removed"). */
743
pSession = shmcb_lookup_session_id(s, &queue, &cache, id, idlen);
745
header->num_retrieves_hit++;
747
header->num_retrieves_miss++;
748
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
749
"leaving shmcb_retrieve_session");
753
static BOOL shmcb_remove_session(
754
server_rec *s, void *shm_segment,
755
UCHAR *id, int idlen)
760
unsigned char masked_index;
763
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
764
"inside shmcb_remove_session");
766
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s, "remove called with NULL session_id!");
770
/* Get the header structure, which division this session remove
771
* will happen in etc. */
772
shmcb_get_header(shm_segment, &header);
773
masked_index = id[0] & header->division_mask;
774
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
775
"id[0]=%u, masked index=%u", id[0], masked_index);
776
if (!shmcb_get_division(header, &queue, &cache, (unsigned int)masked_index)) {
777
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s, "shmcb_remove_session, internal error");
778
header->num_removes_miss++;
781
res = shmcb_remove_session_id(s, &queue, &cache, id, idlen);
783
header->num_removes_hit++;
785
header->num_removes_miss++;
786
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
787
"leaving shmcb_remove_session");
794
** Weirdo cyclic buffer functions
798
/* This gets used in the cyclic "index array" (in the 'Queue's) and
799
* in the cyclic 'Cache's too ... you provide the "width" of the
800
* cyclic store, the starting position and how far to move (with
801
* wrapping if necessary). Basically it's addition modulo buf_size. */
802
static unsigned int shmcb_cyclic_increment(
803
unsigned int buf_size,
804
unsigned int start_pos,
808
while (start_pos >= buf_size)
809
start_pos -= buf_size;
813
/* Given two positions in a cyclic buffer, calculate the "distance".
814
* This is to cover the case ("non-trivial") where the 'next' offset
815
* is to the left of the 'start' offset. NB: This calculates the
816
* space inclusive of one end-point but not the other. There is an
817
* ambiguous case (which is why we use the <start_pos,offset>
818
* coordinate system rather than <start_pos,end_pos> one) when 'start'
819
* is the same as 'next'. It could indicate the buffer is full or it
820
* can indicate the buffer is empty ... I choose the latter as it's
821
* easier and usually necessary to check if the buffer is full anyway
822
* before doing incremental logic (which is this useful for), but we
823
* definitely need the empty case handled - in fact it's our starting
825
static unsigned int shmcb_cyclic_space(
826
unsigned int buf_size,
827
unsigned int start_offset,
828
unsigned int next_offset)
830
/* Is it the trivial case? */
831
if (start_offset <= next_offset)
832
return (next_offset - start_offset); /* yes */
834
return ((buf_size - start_offset) + next_offset); /* no */
837
/* A "normal-to-cyclic" memcpy ... this takes a linear block of
838
* memory and copies it onto a cyclic buffer. The purpose and
839
* function of this is pretty obvious, you need to cover the case
840
* that the destination (cyclic) buffer has to wrap round. */
841
static void shmcb_cyclic_ntoc_memcpy(
842
unsigned int buf_size,
844
unsigned int dest_offset,
845
unsigned char *src, unsigned int src_len)
847
/* Cover the case that src_len > buf_size */
848
if (src_len > buf_size)
851
/* Can it be copied all in one go? */
852
if (dest_offset + src_len < buf_size)
854
memcpy(data + dest_offset, src, src_len);
857
memcpy(data + dest_offset, src, buf_size - dest_offset);
858
memcpy(data, src + buf_size - dest_offset,
859
src_len + dest_offset - buf_size);
864
/* A "cyclic-to-normal" memcpy ... given the last function, this
865
* one's purpose is clear, it copies out of a cyclic buffer handling
867
static void shmcb_cyclic_cton_memcpy(
868
unsigned int buf_size,
871
unsigned int src_offset,
872
unsigned int src_len)
874
/* Cover the case that src_len > buf_size */
875
if (src_len > buf_size)
878
/* Can it be copied all in one go? */
879
if (src_offset + src_len < buf_size)
881
memcpy(dest, data + src_offset, src_len);
884
memcpy(dest, data + src_offset, buf_size - src_offset);
885
memcpy(dest + buf_size - src_offset, data,
886
src_len + src_offset - buf_size);
891
/* Here's the cool hack that makes it all work ... by simply
892
* making the first collection of bytes *be* our header structure
893
* (casting it into the C structure), we have the perfect way to
894
* maintain state in a shared-memory session cache from one call
895
* (and process) to the next, use the shared memory itself! The
896
* original mod_ssl shared-memory session cache uses variables
897
* inside the context, but we simply use that for storing the
898
* pointer to the shared memory itself. And don't forget, after
899
* Apache's initialisation, this "header" is constant/read-only
900
* so we can read it outside any locking.
901
* <grin> - sometimes I just *love* coding y'know?! */
902
static void shmcb_get_header(void *shm_mem, SHMCBHeader **header)
904
*header = (SHMCBHeader *)shm_mem;
908
/* This is what populates our "interesting" structures. Given a
909
* pointer to the header, and an index into the appropriate
910
* division (this must have already been masked using the
911
* division_mask by the caller!), we can populate the provided
912
* SHMCBQueue and SHMCBCache structures with values and
913
* pointers to the underlying shared memory. Upon returning
914
* (if not FALSE), the caller can meddle with the pointer
915
* values and they will map into the shared-memory directly,
916
* as such there's no need to "free" or "set" the Queue or
917
* Cache values, they were themselves references to the *real*
919
static BOOL shmcb_get_division(
920
SHMCBHeader *header, SHMCBQueue *queue,
921
SHMCBCache *cache, unsigned int idx)
923
unsigned char *pQueue;
924
unsigned char *pCache;
927
if (idx > (unsigned int) header->division_mask)
930
/* Locate the blocks of memory storing the corresponding data */
931
pQueue = ((unsigned char *) header) + header->division_offset +
932
(idx * header->division_size);
933
pCache = pQueue + header->queue_size;
935
/* Populate the structures with appropriate pointers */
936
queue->first_pos = (unsigned int *) pQueue;
938
/* Our structures stay packed, no matter what the system's
939
* data-alignment regime is. */
940
queue->pos_count = (unsigned int *) (pQueue + sizeof(unsigned int));
941
queue->indexes = (SHMCBIndex *) (pQueue + (2 * sizeof(unsigned int)));
942
cache->first_pos = (unsigned int *) pCache;
943
cache->pos_count = (unsigned int *) (pCache + sizeof(unsigned int));
944
cache->data = (unsigned char *) (pCache + (2 * sizeof(unsigned int)));
945
queue->header = cache->header = header;
950
/* This returns a pointer to the piece of shared memory containing
951
* a specified 'Index'. SHMCBIndex, like SHMCBHeader, is a fixed
952
* width non-referencing structure of primitive types that can be
953
* cast onto the corresponding block of shared memory. Thus, by
954
* returning a cast pointer to that section of shared memory, the
955
* caller can read and write values to and from the "structure" and
956
* they are actually reading and writing the underlying shared
958
static SHMCBIndex *shmcb_get_index(
959
const SHMCBQueue *queue, unsigned int idx)
962
if (idx > queue->header->index_num)
965
/* Return a pointer to the index. NB: I am being horribly pendantic
966
* here so as to avoid any potential data-alignment assumptions being
967
* placed on the pointer arithmetic by the compiler (sigh). */
968
return (SHMCBIndex *)(((unsigned char *) queue->indexes) +
969
(idx * sizeof(SHMCBIndex)));
972
/* This functions rolls expired cache (and index) entries off the front
973
* of the cyclic buffers in a division. The function returns the number
974
* of expired sessions. */
975
static unsigned int shmcb_expire_division(
976
server_rec *s, SHMCBQueue *queue, SHMCBCache *cache)
980
unsigned int loop, index_num, pos_count, new_pos;
983
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
984
"entering shmcb_expire_division");
986
/* We must calculate num and space ourselves based on expiry times. */
989
new_pos = shmcb_get_safe_uint(queue->first_pos);
991
/* Cache useful values */
992
header = queue->header;
993
index_num = header->index_num;
994
pos_count = shmcb_get_safe_uint(queue->pos_count);
995
while (loop < pos_count) {
996
idx = shmcb_get_index(queue, new_pos);
997
if (shmcb_get_safe_time(&(idx->expires)) > now)
998
/* it hasn't expired yet, we're done iterating */
1000
/* This one should be expired too. Shift to the next entry. */
1002
new_pos = shmcb_cyclic_increment(index_num, new_pos, 1);
1005
/* Find the new_offset and make the expiries happen. */
1007
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1008
"will be expiring %u sessions", loop);
1009
/* We calculate the new_offset by "peeking" (or in the
1010
* case it's the last entry, "sneaking" ;-). */
1011
if (loop == pos_count) {
1012
/* We are expiring everything! This is easy to do... */
1013
shmcb_set_safe_uint(queue->pos_count, 0);
1014
shmcb_set_safe_uint(cache->pos_count, 0);
1017
/* The Queue is easy to adjust */
1018
shmcb_set_safe_uint(queue->pos_count,
1019
shmcb_get_safe_uint(queue->pos_count) - loop);
1020
shmcb_set_safe_uint(queue->first_pos, new_pos);
1021
/* peek to the start of the next session */
1022
idx = shmcb_get_index(queue, new_pos);
1023
/* We can use shmcb_cyclic_space because we've guaranteed
1024
* we don't fit the ambiguous full/empty case. */
1025
shmcb_set_safe_uint(cache->pos_count,
1026
shmcb_get_safe_uint(cache->pos_count) -
1027
shmcb_cyclic_space(header->cache_data_size,
1028
shmcb_get_safe_uint(cache->first_pos),
1029
shmcb_get_safe_uint(&(idx->offset))));
1030
shmcb_set_safe_uint(cache->first_pos, shmcb_get_safe_uint(&(idx->offset)));
1032
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1033
"we now have %u sessions",
1034
shmcb_get_safe_uint(queue->pos_count));
1036
header->num_expiries += loop;
1040
/* Inserts a new encoded session into a queue/cache pair - expiring
1041
* (early or otherwise) any leading sessions as necessary to ensure
1042
* there is room. An error return (FALSE) should only happen in the
1043
* event of surreal values being passed on, or ridiculously small
1044
* cache sizes. NB: For tracing purposes, this function is also given
1045
* the server_rec to allow "ssl_log()". */
1046
static BOOL shmcb_insert_encoded_session(
1047
server_rec *s, SHMCBQueue * queue,
1049
unsigned char *encoded,
1050
unsigned int encoded_len,
1051
unsigned char *session_id,
1054
SHMCBHeader *header;
1055
SHMCBIndex *idx = NULL;
1056
unsigned int gap, new_pos, loop, new_offset;
1059
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1060
"entering shmcb_insert_encoded_session, "
1061
"*queue->pos_count = %u",
1062
shmcb_get_safe_uint(queue->pos_count));
1064
/* If there's entries to expire, ditch them first thing. */
1065
shmcb_expire_division(s, queue, cache);
1066
header = cache->header;
1067
gap = header->cache_data_size - shmcb_get_safe_uint(cache->pos_count);
1068
if (gap < encoded_len) {
1069
new_pos = shmcb_get_safe_uint(queue->first_pos);
1071
need = (int) encoded_len - (int) gap;
1072
while ((need > 0) && (loop + 1 < shmcb_get_safe_uint(queue->pos_count))) {
1073
new_pos = shmcb_cyclic_increment(header->index_num, new_pos, 1);
1075
idx = shmcb_get_index(queue, new_pos);
1076
need = (int) encoded_len - (int) gap -
1077
shmcb_cyclic_space(header->cache_data_size,
1078
shmcb_get_safe_uint(cache->first_pos),
1079
shmcb_get_safe_uint(&(idx->offset)));
1082
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1083
"about to scroll %u sessions from %u",
1084
loop, shmcb_get_safe_uint(queue->pos_count));
1085
/* We are removing "loop" items from the cache. */
1086
shmcb_set_safe_uint(cache->pos_count,
1087
shmcb_get_safe_uint(cache->pos_count) -
1088
shmcb_cyclic_space(header->cache_data_size,
1089
shmcb_get_safe_uint(cache->first_pos),
1090
shmcb_get_safe_uint(&(idx->offset))));
1091
shmcb_set_safe_uint(cache->first_pos, shmcb_get_safe_uint(&(idx->offset)));
1092
shmcb_set_safe_uint(queue->pos_count, shmcb_get_safe_uint(queue->pos_count) - loop);
1093
shmcb_set_safe_uint(queue->first_pos, new_pos);
1094
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1095
"now only have %u sessions",
1096
shmcb_get_safe_uint(queue->pos_count));
1097
/* Update the stats!!! */
1098
header->num_scrolled += loop;
1102
/* probably unecessary checks, but I'll leave them until this code
1104
if (shmcb_get_safe_uint(cache->pos_count) + encoded_len >
1105
header->cache_data_size) {
1106
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
1107
"shmcb_insert_encoded_session internal error");
1110
if (shmcb_get_safe_uint(queue->pos_count) == header->index_num) {
1111
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
1112
"shmcb_insert_encoded_session internal error");
1115
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1116
"we have %u bytes and %u indexes free - enough",
1117
header->cache_data_size -
1118
shmcb_get_safe_uint(cache->pos_count), header->index_num -
1119
shmcb_get_safe_uint(queue->pos_count));
1122
/* HERE WE ASSUME THAT THE NEW SESSION SHOULD GO ON THE END! I'M NOT
1123
* CHECKING WHETHER IT SHOULD BE GENUINELY "INSERTED" SOMEWHERE.
1125
* We either fix that, or find out at a "higher" (read "mod_ssl")
1126
* level whether it is possible to have distinct session caches for
1127
* any attempted tomfoolery to do with different session timeouts.
1128
* Knowing in advance that we can have a cache-wide constant timeout
1129
* would make this stuff *MUCH* more efficient. Mind you, it's very
1130
* efficient right now because I'm ignoring this problem!!!
1133
/* Increment to the first unused byte */
1134
new_offset = shmcb_cyclic_increment(header->cache_data_size,
1135
shmcb_get_safe_uint(cache->first_pos),
1136
shmcb_get_safe_uint(cache->pos_count));
1137
/* Copy the DER-encoded session into place */
1138
shmcb_cyclic_ntoc_memcpy(header->cache_data_size, cache->data,
1139
new_offset, encoded, encoded_len);
1140
/* Get the new index that this session is stored in. */
1141
new_pos = shmcb_cyclic_increment(header->index_num,
1142
shmcb_get_safe_uint(queue->first_pos),
1143
shmcb_get_safe_uint(queue->pos_count));
1144
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1145
"storing in index %u, at offset %u",
1146
new_pos, new_offset);
1147
idx = shmcb_get_index(queue, new_pos);
1149
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
1150
"shmcb_insert_encoded_session internal error");
1153
shmcb_safe_clear(idx, sizeof(SHMCBIndex));
1154
shmcb_set_safe_time(&(idx->expires), expiry_time);
1155
shmcb_set_safe_uint(&(idx->offset), new_offset);
1157
/* idx->removed = (unsigned char)0; */ /* Not needed given the memset above. */
1158
idx->s_id2 = session_id[1];
1159
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1160
"session_id[0]=%u, idx->s_id2=%u",
1161
session_id[0], session_id[1]);
1163
/* All that remains is to adjust the cache's and queue's "pos_count"s. */
1164
shmcb_set_safe_uint(cache->pos_count,
1165
shmcb_get_safe_uint(cache->pos_count) + encoded_len);
1166
shmcb_set_safe_uint(queue->pos_count,
1167
shmcb_get_safe_uint(queue->pos_count) + 1);
1169
/* And just for good debugging measure ... */
1170
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1171
"leaving now with %u bytes in the cache and %u indexes",
1172
shmcb_get_safe_uint(cache->pos_count),
1173
shmcb_get_safe_uint(queue->pos_count));
1174
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1175
"leaving shmcb_insert_encoded_session");
1179
/* Performs a lookup into a queue/cache pair for a
1180
* session_id. If found, the session is deserialised
1181
* and returned, otherwise NULL. */
1182
static SSL_SESSION *shmcb_lookup_session_id(
1183
server_rec *s, SHMCBQueue *queue,
1184
SHMCBCache *cache, UCHAR *id,
1187
unsigned char tempasn[SSL_SESSION_MAX_DER];
1189
SHMCBHeader *header;
1190
SSL_SESSION *pSession = NULL;
1191
unsigned int curr_pos, loop, count;
1192
MODSSL_D2I_SSL_SESSION_CONST unsigned char *ptr;
1195
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1196
"entering shmcb_lookup_session_id");
1198
/* If there are entries to expire, ditch them first thing. */
1199
shmcb_expire_division(s, queue, cache);
1201
curr_pos = shmcb_get_safe_uint(queue->first_pos);
1202
count = shmcb_get_safe_uint(queue->pos_count);
1203
header = queue->header;
1204
for (loop = 0; loop < count; loop++) {
1205
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1206
"loop=%u, count=%u, curr_pos=%u",
1207
loop, count, curr_pos);
1208
idx = shmcb_get_index(queue, curr_pos);
1209
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1210
"idx->s_id2=%u, id[1]=%u, offset=%u",
1211
idx->s_id2, id[1], shmcb_get_safe_uint(&(idx->offset)));
1212
/* Only look into the session further if;
1213
* (a) the second byte of the session_id matches,
1214
* (b) the "removed" flag isn't set,
1215
* (c) the session hasn't expired yet.
1216
* We do (c) like this so that it saves us having to
1217
* do natural expiries ... naturally expired sessions
1218
* scroll off the front anyway when the cache is full and
1219
* "rotating", the only real issue that remains is the
1220
* removal or disabling of forcibly killed sessions. */
1221
if ((idx->s_id2 == id[1]) && !idx->removed &&
1222
(shmcb_get_safe_time(&(idx->expires)) > now)) {
1223
unsigned int session_id_length;
1224
unsigned char *session_id;
1226
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1227
"at index %u, found possible session match",
1229
shmcb_cyclic_cton_memcpy(header->cache_data_size,
1230
tempasn, cache->data,
1231
shmcb_get_safe_uint(&(idx->offset)),
1232
SSL_SESSION_MAX_DER);
1234
pSession = d2i_SSL_SESSION(NULL, &ptr, SSL_SESSION_MAX_DER);
1235
session_id_length = SSL_SESSION_get_session_id_length(pSession);
1236
session_id = SSL_SESSION_get_session_id(pSession);
1238
if (pSession == NULL) {
1239
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
1240
"scach2_lookup_session_id internal error");
1243
if ((session_id_length == idlen) &&
1244
(memcmp(session_id, id, idlen) == 0)) {
1245
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1249
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1251
SSL_SESSION_free(pSession);
1254
curr_pos = shmcb_cyclic_increment(header->index_num, curr_pos, 1);
1256
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1257
"no matching sessions were found");
1261
static BOOL shmcb_remove_session_id(
1262
server_rec *s, SHMCBQueue *queue,
1263
SHMCBCache *cache, UCHAR *id, unsigned int idlen)
1265
unsigned char tempasn[SSL_SESSION_MAX_DER];
1266
SSL_SESSION *pSession = NULL;
1268
SHMCBHeader *header;
1269
unsigned int curr_pos, loop, count;
1270
MODSSL_D2I_SSL_SESSION_CONST unsigned char *ptr;
1271
BOOL to_return = FALSE;
1273
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1274
"entering shmcb_remove_session_id");
1276
/* If there's entries to expire, ditch them first thing. */
1277
/* shmcb_expire_division(s, queue, cache); */
1279
/* Regarding the above ... hmmm ... I know my expiry code is slightly
1280
* "faster" than all this remove stuff ... but if the higher level
1281
* code calls a "remove" operation (and this *only* seems to happen
1282
* when it has spotted an expired session before we had a chance to)
1283
* then it should get credit for a remove (stats-wise). Also, in the
1284
* off-chance that the server *requests* a renegotiate and wants to
1285
* wipe the session clean we should give that priority over our own
1286
* routine expiry handling. So I've moved the expiry check to *after*
1287
* this general remove stuff. */
1288
curr_pos = shmcb_get_safe_uint(queue->first_pos);
1289
count = shmcb_get_safe_uint(queue->pos_count);
1290
header = cache->header;
1291
for (loop = 0; loop < count; loop++) {
1292
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1293
"loop=%u, count=%u, curr_pos=%u",
1294
loop, count, curr_pos);
1295
idx = shmcb_get_index(queue, curr_pos);
1296
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1297
"idx->s_id2=%u, id[1]=%u", idx->s_id2,
1299
/* Only look into the session further if the second byte of the
1300
* session_id matches. */
1301
if (idx->s_id2 == id[1]) {
1302
unsigned int session_id_length;
1303
unsigned char *session_id;
1305
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1306
"at index %u, found possible "
1307
"session match", curr_pos);
1308
shmcb_cyclic_cton_memcpy(header->cache_data_size,
1309
tempasn, cache->data,
1310
shmcb_get_safe_uint(&(idx->offset)),
1311
SSL_SESSION_MAX_DER);
1313
pSession = d2i_SSL_SESSION(NULL, &ptr, SSL_SESSION_MAX_DER);
1314
if (pSession == NULL) {
1315
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,
1316
"shmcb_remove_session_id, internal error");
1319
session_id_length = SSL_SESSION_get_session_id_length(pSession);
1320
session_id = SSL_SESSION_get_session_id(pSession);
1322
if ((session_id_length == idlen)
1323
&& (memcmp(id, session_id, idlen) == 0)) {
1324
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1326
/* Scrub out this session "quietly" */
1327
idx->removed = (unsigned char) 1;
1328
SSL_SESSION_free(pSession);
1332
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1334
SSL_SESSION_free(pSession);
1337
curr_pos = shmcb_cyclic_increment(header->index_num, curr_pos, 1);
1339
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1340
"no matching sessions were found");
1342
/* If there's entries to expire, ditch them now. */
1343
shmcb_expire_division(s, queue, cache);
1345
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
1346
"leaving shmcb_remove_session_id");
added
removed
modules/ssl/ssl_scache_shmcb.c
