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Migrate to OpenSSL 3.0 in advance of FreeBSD 14.0. OpenSSL 1.1.1 (the version we were previously using) will be EOL as of 2023-09-11. Most of the base system has already been updated for a seamless switch to OpenSSL 3.0. For many components we've added `-DOPENSSL_API_COMPAT=0x10100000L` to CFLAGS to specify the API version, which avoids deprecation warnings from OpenSSL 3.0. Changes have also been made to avoid OpenSSL APIs that were already deprecated in OpenSSL 1.1.1. The process of updating to contemporary APIs can continue after this merge. Additional changes are still required for libarchive and Kerberos- related libraries or tools; workarounds will immediately follow this commit. Fixes are in progress in the upstream projects and will be incorporated when those are next updated. There are some performance regressions in benchmarks (certain tests in `openssl speed`) and in some OpenSSL consumers in ports (e.g. haproxy). Investigation will continue for these. Netflix's testing showed no functional regression and a rather small, albeit statistically significant, increase in CPU consumption with OpenSSL 3.0. Thanks to ngie@ and des@ for updating base system components, to antoine@ and bofh@ for ports exp-runs and port fixes/workarounds, and to Netflix and everyone who tested prior to commit or contributed to this update in other ways. PR: 271615 PR: 271656 [exp-run] Relnotes: Yes Sponsored by: The FreeBSD Foundation
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State Machine Design
This file provides some guidance on the thinking behind the design of the state machine code to aid future maintenance.
The state machine code replaces an older state machine present in OpenSSL versions 1.0.2 and below. The new state machine has the following objectives:
- Remove duplication of state code between client and server
- Remove duplication of state code between TLS and DTLS
- Simplify transitions and bring the logic together in a single location so that it is easier to validate
- Remove duplication of code between each of the message handling functions
- Receive a message first and then work out whether that is a valid transition - not the other way around (the other way causes lots of issues where we are expecting one type of message next but actually get something else)
- Separate message flow state from handshake state (in order to better
understand each)
- message flow state = when to flush buffers; handling restarts in the event of NBIO events; handling the common flow of steps for reading a message and the common flow of steps for writing a message etc
- handshake state = what handshake message are we working on now
- Control complexity: only the state machine can change state: keep all the state changes local to the state machine component
The message flow state machine is divided into a reading sub-state machine and a writing sub-state machine. See the source comments in statem.c for a more detailed description of the various states and transitions possible.
Conceptually the state machine component is designed as follows:
libssl
|
-------------------------|-----statem.h------------------------------------
|
_______V____________________
| |
| statem.c |
| |
| Core state machine code |
|____________________________|
statem_local.h ^ ^
_________| |_______
| |
_____________|____________ _____________|____________
| | | |
| statem_clnt.c | | statem_srvr.c |
| | | |
| TLS/DTLS client specific | | TLS/DTLS server specific |
| state machine code | | state machine code |
|__________________________| |__________________________|
| |_______________|__ |
| ________________| | |
| | | |
____________V_______V________ ________V______V_______________
| | | |
| statem_lib.c | | statem_dtls.c |
| | | |
| Non core functions common | | Non core functions common to |
| to both servers and clients | | both DTLS servers and clients |
|_____________________________| |_______________________________|