# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at
http://mozilla.org/MPL/2.0/.
SSL's Buffers: enumerated and explained.
---------------------------------------------------------------------------
incoming:
gs = ss->gather
hs = ss->ssl3->hs
gs->inbuf incoming (encrypted) ssl records are placed here,
and then decrypted (or copied) to gs->buf.
gs->buf ssl3_HandleHandshake puts decrypted ssl records here.
hs.msg_body When an incoming handshake message spans more
than one ssl record, the first part(s) of it are accumulated
here until it all arrives.
hs.msgState an alternative set of pointers/lengths for gs->buf.
Used only when a handleHandshake function returns SECWouldBlock.
ssl3_HandleHandshake remembers how far it previously got by
using these pointers instead of gs->buf when it is called
after a previous SECWouldBlock return.
---------------------------------------------------------------------------
outgoing:
sec = ss->sec
ci = ss->sec->ci /* connect info */
ci->sendBuf Outgoing handshake messages are appended to this buffer.
This buffer will then be sent as a single SSL record.
sec->writeBuf outgoing ssl records are constructed here and encrypted in
place before being written or copied to pendingBuf.
ss->pendingBuf contains outgoing ciphertext that was saved after a write
attempt to the socket failed, e.g. EWouldBlock.
Generally empty with blocking sockets (should be no incomplete
writes).
ss->saveBuf Used only by socks code. Intended to be used to buffer
outgoing data until a socks handshake completes. However,
this buffer is always empty. There is no code to put
anything into it.
---------------------------------------------------------------------------
SECWouldBlock means that the function cannot make progress because it is
waiting for some event OTHER THAN socket I/O completion (e.g. waiting for
user dialog to finish). It is not the same as EWOULDBLOCK.
---------------------------------------------------------------------------
Rank (order) of locks
recvLock ->\ firstHandshake -> recvbuf -> ssl3Handshake -> xmitbuf -> "spec"
sendLock ->/
crypto and hash Data that must be protected while turning plaintext into
ciphertext:
SSl3: (in ssl3_SendPlainText)
ss->ssl3 (the pointer)
ss->ssl3->current_write* (the pointer and the data in the spec
and any data referenced by the spec.
ss->sec->isServer
ss->sec->writebuf* (ptr & content) locked by xmitBufLock
"buf" locked by xmitBufLock
crypto and hash data that must be protected while turning ciphertext into
plaintext:
SSL3: (in ssl3_HandleRecord )
ssl3->current_read* (the pointer and all data refernced)
ss->sec->isServer
Data that must be protected while being used by a "writer":
ss->pendingBuf.*
ss->saveBuf.* (which is dead)
in ssl3_sendPlainText
ss->ssl3->current_write-> (spec)
ss->sec->writeBuf.*
ss->sec->isServer
in SendBlock
ss->sec->writeBuf.*
ss->pendingBuf
--------------------------------------------------------------------------
Data variables (not const) protected by the "sslGlobalDataLock".
Note, this really should be a reader/writer lock.
cipherSuites[] ssl3con.c
