- choice where to enter passphrase is now made on the host
- use wipeable string in the comm stack
- wipe passphrase memory
- protocol optimizations, prepare for new firmware version
- minor fixes and improvements
- tests fixes, HF12 support
- Add abstract_http_client.h which http_client.h extends.
- Replace simple_http_client with abstract_http_client in wallet2,
message_store, message_transporter, and node_rpc_proxy.
- Import and export wallet data in wallet2.
- Use #if defined __EMSCRIPTEN__ directives to skip incompatible code.
81c5943 Remove temporary std::string creation in some hex->bin calls (vtnerd)
5fcc23a Move hex->bin conversion to monero copyright files and with less includes (vtnerd)
3387f0e Reduce template bloat in hex->bin for ZMQ json (vtnerd)
When a handshake fails, it can fail due to timeout or destroyed
connection, in which case the connection will be, or already is,
closed, and we don't want to do it twice.
Additionally, when closing a connection directly from the top
level code, ensure the connection is gone from the m_connects
list so it won't be used again.
AFAICT this is now clean in netstat, /proc/PID/fd and print_cn.
This fixes a noisy (but harmless) exception.
760ecf2 console_handler: do not let exception past the dor (moneromooo-monero)
09c8111 threadpool: lock mutex in create (moneromooo-monero)
e377977 tx_pool: catch theoretical error in get_block_reward (moneromooo-monero)
5.7.1 was removed from official qt.io archive, this is one of the few mirrors remaining that keep a copy.
I think it would be better if @TheCharlatan updated to a newer version soon than merging this PR
4771a7ae p2p: remove obsolete local time in handshake (moneromooo-monero)
2fbbc4a2 p2p: avoid sending the same peer list over and over (moneromooo-monero)
3004835b epee: remove backward compatible endian specific address serialization (moneromooo-monero)
39a343d7 p2p: remove backward compatible peer list (moneromooo-monero)
60631802 p2p: simplify last_seen serialization now we have optional stores (moneromooo-monero)
9467b2e4 cryptonote_protocol: omit top 64 bits of difficulty when 0 (moneromooo-monero)
b595583f serialization: do not write optional fields with default value (moneromooo-monero)
5f98b46d p2p: remove obsolete local time from TIMED_SYNC (moneromooo-monero)
- Finding handling function in ZMQ JSON-RPC now uses binary search
- Temporary `std::vector`s in JSON output now use `epee::span` to
prevent allocations.
- Binary -> hex in JSON output no longer allocates temporary buffer
- C++ structs -> JSON skips intermediate DOM creation, and instead
write directly to an output stream.
The implicit copy assignment operator was deprecated because the class
has an explicit copy constructor. According to the standard:
The generation of the implicitly-defined copy assignment operator is
deprecated (since C++11) if T has a user-declared destructor or
user-declared copy constructor.
Recent versions of gcc (9.1+) and clang (10.0) warn about this.
boost::asio::ssl::context is created using specifically TLSv1.2, which
blocks the ability to use superior version of TLS like TLSv1.3.
Filtering is also made specially later in the code to remove unsafe
version for TLS such SSLv2, SSLv3 etc..
This change is removing double filtering to allow TLSv1.2 and above to
be used.
testssl.sh 3.0rc5 now reports the following (please note monerod was
built with USE_EXTRA_EC_CERT):
$ ./testssl.sh --openssl=/usr/bin/openssl \
--each-cipher --cipher-per-proto \
--server-defaults --server-preference \
--vulnerable --heartbleed --ccs --ticketbleed \
--robot --renegotiation --compression --breach \
--poodle --tls-fallback --sweet32 --beast --lucky13 \
--freak --logjam --drown --pfs --rc4 --full \
--wide --hints 127.0.0.1:38081
Using "OpenSSL 1.1.1d 10 Sep 2019" [~80 ciphers]
on ip-10-97-15-6:/usr/bin/openssl
(built: "Dec 3 21:14:51 2019", platform: "linux-x86_64")
Start 2019-12-03 21:51:25 -->> 127.0.0.1:38081 (127.0.0.1) <<--
rDNS (127.0.0.1): --
Service detected: HTTP
Testing protocols via sockets except NPN+ALPN
SSLv2 not offered (OK)
SSLv3 not offered (OK)
TLS 1 not offered
TLS 1.1 not offered
TLS 1.2 offered (OK)
TLS 1.3 offered (OK): final
NPN/SPDY not offered
ALPN/HTTP2 not offered
Testing for server implementation bugs
No bugs found.
Testing cipher categories
NULL ciphers (no encryption) not offered (OK)
Anonymous NULL Ciphers (no authentication) not offered (OK)
Export ciphers (w/o ADH+NULL) not offered (OK)
LOW: 64 Bit + DES, RC[2,4] (w/o export) not offered (OK)
Triple DES Ciphers / IDEA not offered (OK)
Average: SEED + 128+256 Bit CBC ciphers not offered
Strong encryption (AEAD ciphers) offered (OK)
Testing robust (perfect) forward secrecy, (P)FS -- omitting Null Authentication/Encryption, 3DES, RC4
PFS is offered (OK), ciphers follow (client/browser support is important here)
Hexcode Cipher Suite Name (OpenSSL) KeyExch. Encryption Bits Cipher Suite Name (IANA/RFC)
-----------------------------------------------------------------------------------------------------------------------------
x1302 TLS_AES_256_GCM_SHA384 ECDH 253 AESGCM 256 TLS_AES_256_GCM_SHA384
x1303 TLS_CHACHA20_POLY1305_SHA256 ECDH 253 ChaCha20 256 TLS_CHACHA20_POLY1305_SHA256
xc030 ECDHE-RSA-AES256-GCM-SHA384 ECDH 253 AESGCM 256 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
xc02c ECDHE-ECDSA-AES256-GCM-SHA384 ECDH 253 AESGCM 256 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
xcca9 ECDHE-ECDSA-CHACHA20-POLY1305 ECDH 253 ChaCha20 256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
xcca8 ECDHE-RSA-CHACHA20-POLY1305 ECDH 253 ChaCha20 256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
x1301 TLS_AES_128_GCM_SHA256 ECDH 253 AESGCM 128 TLS_AES_128_GCM_SHA256
xc02f ECDHE-RSA-AES128-GCM-SHA256 ECDH 253 AESGCM 128 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
xc02b ECDHE-ECDSA-AES128-GCM-SHA256 ECDH 253 AESGCM 128 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
Elliptic curves offered: prime256v1 secp384r1 secp521r1 X25519 X448
Testing server preferences
Has server cipher order? yes (OK)
Negotiated protocol TLSv1.3
Negotiated cipher TLS_AES_256_GCM_SHA384, 253 bit ECDH (X25519)
Cipher order
TLSv1.2: ECDHE-ECDSA-CHACHA20-POLY1305 ECDHE-ECDSA-AES256-GCM-SHA384 ECDHE-ECDSA-AES128-GCM-SHA256 ECDHE-RSA-CHACHA20-POLY1305 ECDHE-RSA-AES256-GCM-SHA384 ECDHE-RSA-AES128-GCM-SHA256
TLSv1.3: TLS_AES_256_GCM_SHA384 TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256
Testing server defaults (Server Hello)
TLS extensions (standard) "renegotiation info/#65281" "EC point formats/#11" "supported versions/#43" "key share/#51" "max fragment length/#1" "extended master secret/#23"
Session Ticket RFC 5077 hint no -- no lifetime advertised
SSL Session ID support yes
Session Resumption Tickets no, ID: no
TLS clock skew Random values, no fingerprinting possible
Server Certificate #1 (in response to request w/o SNI)
Signature Algorithm SHA256 with RSA
Server key size RSA 4096 bits
Server key usage --
Server extended key usage --
Serial / Fingerprints 01 / SHA1 132E42981812F5575FA0AE64922B18A81B38C03F
SHA256 EBA3CC4AA09DEF26706E64A70DB4BC8D723533BB67EAE12B503A845019FB61DC
Common Name (CN) (no CN field in subject)
subjectAltName (SAN) missing (NOT ok) -- Browsers are complaining
Issuer
Trust (hostname) certificate does not match supplied URI
Chain of trust NOT ok (self signed)
EV cert (experimental) no
"eTLS" (visibility info) not present
Certificate Validity (UTC) 181 >= 60 days (2019-12-03 21:51 --> 2020-06-02 21:51)
# of certificates provided 1
Certificate Revocation List --
OCSP URI --
NOT ok -- neither CRL nor OCSP URI provided
OCSP stapling not offered
OCSP must staple extension --
DNS CAA RR (experimental) not offered
Certificate Transparency --
Server Certificate #2 (in response to request w/o SNI)
Signature Algorithm ECDSA with SHA256
Server key size EC 256 bits
Server key usage --
Server extended key usage --
Serial / Fingerprints 01 / SHA1 E17B765DD8124525B1407E827B89A31FB167647D
SHA256 AFB7F44B1C33831F521357E5AEEB813044CB02532143E92D35650A3FF792A7C3
Common Name (CN) (no CN field in subject)
subjectAltName (SAN) missing (NOT ok) -- Browsers are complaining
Issuer
Trust (hostname) certificate does not match supplied URI
Chain of trust NOT ok (self signed)
EV cert (experimental) no
"eTLS" (visibility info) not present
Certificate Validity (UTC) 181 >= 60 days (2019-12-03 21:51 --> 2020-06-02 21:51)
# of certificates provided 1
Certificate Revocation List --
OCSP URI --
NOT ok -- neither CRL nor OCSP URI provided
OCSP stapling not offered
OCSP must staple extension --
DNS CAA RR (experimental) not offered
Certificate Transparency --
Testing HTTP header response @ "/"
HTTP Status Code 404 Not found (Hint: supply a path which doesn't give a "404 Not found")
HTTP clock skew Got no HTTP time, maybe try different URL?
Strict Transport Security not offered
Public Key Pinning --
Server banner Epee-based
Application banner --
Cookie(s) (none issued at "/") -- maybe better try target URL of 30x
Security headers --
Reverse Proxy banner --
Testing vulnerabilities
Heartbleed (CVE-2014-0160) not vulnerable (OK), no heartbeat extension
CCS (CVE-2014-0224) not vulnerable (OK)
Ticketbleed (CVE-2016-9244), experiment. not vulnerable (OK), no session ticket extension
ROBOT Server does not support any cipher suites that use RSA key transport
Secure Renegotiation (CVE-2009-3555) not vulnerable (OK)
Secure Client-Initiated Renegotiation not vulnerable (OK)
CRIME, TLS (CVE-2012-4929) not vulnerable (OK)
BREACH (CVE-2013-3587) no HTTP compression (OK) - only supplied "/" tested
POODLE, SSL (CVE-2014-3566) not vulnerable (OK)
TLS_FALLBACK_SCSV (RFC 7507) No fallback possible, no protocol below TLS 1.2 offered (OK)
SWEET32 (CVE-2016-2183, CVE-2016-6329) not vulnerable (OK)
FREAK (CVE-2015-0204) not vulnerable (OK)
DROWN (CVE-2016-0800, CVE-2016-0703) not vulnerable on this host and port (OK)
make sure you don't use this certificate elsewhere with SSLv2 enabled services
https://censys.io/ipv4?q=EBA3CC4AA09DEF26706E64A70DB4BC8D723533BB67EAE12B503A845019FB61DC could help you to find out
LOGJAM (CVE-2015-4000), experimental not vulnerable (OK): no DH EXPORT ciphers, no DH key detected with <= TLS 1.2
BEAST (CVE-2011-3389) no SSL3 or TLS1 (OK)
LUCKY13 (CVE-2013-0169), experimental not vulnerable (OK)
RC4 (CVE-2013-2566, CVE-2015-2808) no RC4 ciphers detected (OK)
Testing ciphers per protocol via OpenSSL plus sockets against the server, ordered by encryption strength
Hexcode Cipher Suite Name (OpenSSL) KeyExch. Encryption Bits Cipher Suite Name (IANA/RFC)
-----------------------------------------------------------------------------------------------------------------------------
SSLv2
SSLv3
TLS 1
TLS 1.1
TLS 1.2
xc030 ECDHE-RSA-AES256-GCM-SHA384 ECDH 253 AESGCM 256 TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
xc02c ECDHE-ECDSA-AES256-GCM-SHA384 ECDH 253 AESGCM 256 TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
xcca9 ECDHE-ECDSA-CHACHA20-POLY1305 ECDH 253 ChaCha20 256 TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
xcca8 ECDHE-RSA-CHACHA20-POLY1305 ECDH 253 ChaCha20 256 TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
xc02f ECDHE-RSA-AES128-GCM-SHA256 ECDH 253 AESGCM 128 TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
xc02b ECDHE-ECDSA-AES128-GCM-SHA256 ECDH 253 AESGCM 128 TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
TLS 1.3
x1302 TLS_AES_256_GCM_SHA384 ECDH 253 AESGCM 256 TLS_AES_256_GCM_SHA384
x1303 TLS_CHACHA20_POLY1305_SHA256 ECDH 253 ChaCha20 256 TLS_CHACHA20_POLY1305_SHA256
x1301 TLS_AES_128_GCM_SHA256 ECDH 253 AESGCM 128 TLS_AES_128_GCM_SHA256
Running client simulations (HTTP) via sockets
Browser Protocol Cipher Suite Name (OpenSSL) Forward Secrecy
------------------------------------------------------------------------------------------------
Android 4.2.2 No connection
Android 4.4.2 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Android 5.0.0 TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256 256 bit ECDH (P-256)
Android 6.0 TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256 256 bit ECDH (P-256)
Android 7.0 TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305 253 bit ECDH (X25519)
Android 8.1 (native) No connection
Android 9.0 (native) TLSv1.3 TLS_AES_256_GCM_SHA384 253 bit ECDH (X25519)
Chrome 65 Win 7 TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305 253 bit ECDH (X25519)
Chrome 74 (Win 10) No connection
Firefox 62 Win 7 TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305 253 bit ECDH (X25519)
Firefox 66 (Win 8.1/10) TLSv1.3 TLS_AES_256_GCM_SHA384 253 bit ECDH (X25519)
IE 6 XP No connection
IE 7 Vista No connection
IE 8 Win 7 No connection
IE 8 XP No connection
IE 11 Win 7 No connection
IE 11 Win 8.1 No connection
IE 11 Win Phone 8.1 No connection
IE 11 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Edge 15 Win 10 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 253 bit ECDH (X25519)
Edge 17 (Win 10) TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 253 bit ECDH (X25519)
Opera 60 (Win 10) No connection
Safari 9 iOS 9 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Safari 9 OS X 10.11 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Safari 10 OS X 10.12 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Apple ATS 9 iOS 9 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Tor 17.0.9 Win 7 No connection
Java 6u45 No connection
Java 7u25 No connection
Java 8u161 TLSv1.2 ECDHE-ECDSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
Java 9.0.4 TLSv1.2 ECDHE-ECDSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
OpenSSL 1.0.1l TLSv1.2 ECDHE-ECDSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
OpenSSL 1.0.2e TLSv1.2 ECDHE-ECDSA-AES256-GCM-SHA384 256 bit ECDH (P-256)
OpenSSL 1.1.0j (Debian) TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305 253 bit ECDH (X25519)
OpenSSL 1.1.1b (Debian) TLSv1.3 TLS_AES_256_GCM_SHA384 253 bit ECDH (X25519)
Thunderbird (60.6) TLSv1.3 TLS_AES_256_GCM_SHA384 253 bit ECDH (X25519)
This fixes rapid reconnections failing as the peer hasn't yet
worked out the other side is gone, and will reject "duplicate"
connections until a timeout.
- Removed copy of field names in binary deserialization
- Removed copy of array values in binary deserialization
- Removed copy of string values in json deserialization
- Removed unhelpful allocation in json string value parsing
- Removed copy of blob data on binary and json serialization
38f691048 simplewallet: plug a timing leak (moneromooo-monero)
dcff02e4c epee: allow a random component in once_a_time timeouts (moneromooo-monero)
e10833024 wallet: reuse cached height when set after refresh (moneromooo-monero)
5956beaa1 wallet2: fix is_synced checking target height, not height (moneromooo-monero)
fd35e2304 wallet: fix another facet of "did I get some monero" information leak (moneromooo-monero)
d5472bd87 wallet2: do not send an unnecessary last getblocks.bin call on refresh (moneromooo-monero)
97ae7bb5c wallet2: do not repeatedly ask for pool txes sent to us (moneromooo-monero)
Make sure it links to our libtinfo from our ncurses build.
Hardcode some basic terminal descriptions into our libtinfo.
Re-enable $HOME/.terminfo support to allow user customization.
Use unlikely terminfo-dir, to prevent accidentally using
differently-configured system databases.
b3a9a4d add a quick early out to get_blocks.bin when up to date (moneromooo-monero)
2899379 daemon, wallet: new pay for RPC use system (moneromooo-monero)
ffa4602 simplewallet: add public_nodes command (moneromooo-monero)
Daemons intended for public use can be set up to require payment
in the form of hashes in exchange for RPC service. This enables
public daemons to receive payment for their work over a large
number of calls. This system behaves similarly to a pool, so
payment takes the form of valid blocks every so often, yielding
a large one off payment, rather than constant micropayments.
This system can also be used by third parties as a "paywall"
layer, where users of a service can pay for use by mining Monero
to the service provider's address. An example of this for web
site access is Primo, a Monero mining based website "paywall":
https://github.com/selene-kovri/primo
This has some advantages:
- incentive to run a node providing RPC services, thereby promoting the availability of third party nodes for those who can't run their own
- incentive to run your own node instead of using a third party's, thereby promoting decentralization
- decentralized: payment is done between a client and server, with no third party needed
- private: since the system is "pay as you go", you don't need to identify yourself to claim a long lived balance
- no payment occurs on the blockchain, so there is no extra transactional load
- one may mine with a beefy server, and use those credits from a phone, by reusing the client ID (at the cost of some privacy)
- no barrier to entry: anyone may run a RPC node, and your expected revenue depends on how much work you do
- Sybil resistant: if you run 1000 idle RPC nodes, you don't magically get more revenue
- no large credit balance maintained on servers, so they have no incentive to exit scam
- you can use any/many node(s), since there's little cost in switching servers
- market based prices: competition between servers to lower costs
- incentive for a distributed third party node system: if some public nodes are overused/slow, traffic can move to others
- increases network security
- helps counteract mining pools' share of the network hash rate
- zero incentive for a payer to "double spend" since a reorg does not give any money back to the miner
And some disadvantages:
- low power clients will have difficulty mining (but one can optionally mine in advance and/or with a faster machine)
- payment is "random", so a server might go a long time without a block before getting one
- a public node's overall expected payment may be small
Public nodes are expected to compete to find a suitable level for
cost of service.
The daemon can be set up this way to require payment for RPC services:
monerod --rpc-payment-address 4xxxxxx \
--rpc-payment-credits 250 --rpc-payment-difficulty 1000
These values are an example only.
The --rpc-payment-difficulty switch selects how hard each "share" should
be, similar to a mining pool. The higher the difficulty, the fewer
shares a client will find.
The --rpc-payment-credits switch selects how many credits are awarded
for each share a client finds.
Considering both options, clients will be awarded credits/difficulty
credits for every hash they calculate. For example, in the command line
above, 0.25 credits per hash. A client mining at 100 H/s will therefore
get an average of 25 credits per second.
For reference, in the current implementation, a credit is enough to
sync 20 blocks, so a 100 H/s client that's just starting to use Monero
and uses this daemon will be able to sync 500 blocks per second.
The wallet can be set to automatically mine if connected to a daemon
which requires payment for RPC usage. It will try to keep a balance
of 50000 credits, stopping mining when it's at this level, and starting
again as credits are spent. With the example above, a new client will
mine this much credits in about half an hour, and this target is enough
to sync 500000 blocks (currently about a third of the monero blockchain).
There are three new settings in the wallet:
- credits-target: this is the amount of credits a wallet will try to
reach before stopping mining. The default of 0 means 50000 credits.
- auto-mine-for-rpc-payment-threshold: this controls the minimum
credit rate which the wallet considers worth mining for. If the
daemon credits less than this ratio, the wallet will consider mining
to be not worth it. In the example above, the rate is 0.25
- persistent-rpc-client-id: if set, this allows the wallet to reuse
a client id across runs. This means a public node can tell a wallet
that's connecting is the same as one that connected previously, but
allows a wallet to keep their credit balance from one run to the
other. Since the wallet only mines to keep a small credit balance,
this is not normally worth doing. However, someone may want to mine
on a fast server, and use that credit balance on a low power device
such as a phone. If left unset, a new client ID is generated at
each wallet start, for privacy reasons.
To mine and use a credit balance on two different devices, you can
use the --rpc-client-secret-key switch. A wallet's client secret key
can be found using the new rpc_payments command in the wallet.
Note: anyone knowing your RPC client secret key is able to use your
credit balance.
The wallet has a few new commands too:
- start_mining_for_rpc: start mining to acquire more credits,
regardless of the auto mining settings
- stop_mining_for_rpc: stop mining to acquire more credits
- rpc_payments: display information about current credits with
the currently selected daemon
The node has an extra command:
- rpc_payments: display information about clients and their
balances
The node will forget about any balance for clients which have
been inactive for 6 months. Balances carry over on node restart.
Usually it's unset, but depends toolchain files set it explicitly
for cross-compiling. Don't override preset values. But make sure
it's set for all x86 / x86_64 builds, not just Linux.
Also make sure -std=c++11 is set for Darwin builds, not all
submodules were getting it consistently before.
Use shorter, prefix-unique directory names
gitian-builder -> builder
gitian-sigs -> sigs
monero-binaries -> out
Just use builder/inputs/monero, no need for 2nd repo clone
Resetting the timer after shutdown was initiated would keep
a reference to the object inside ASIO, which would keep the
connection alive until the timer timed out
The problem actually exists in two parts:
1. When sending chunks over a connection, if the queue size is
greater than N, the seed is predictable across every monero node.
>"If rand() is used before any calls to srand(), rand() behaves as if
it was seeded with srand(1). Each time rand() is seeded with the same seed, it
must produce the same sequence of values."
2. The CID speaks for itself: "'rand' should not be used for security-related
applications, because linear congruential algorithms are too easy to break."
*But* this is an area of contention.
One could argue that a CSPRNG is warranted in order to fully mitigate any
potential timing attacks based on crafting chunk responses. Others could argue
that the existing LCG, or even an MTG, would suffice (if properly seeded). As a
compromise, I've used an MTG with a full bit space. This should give a healthy
balance of security and speed without relying on the existing crypto library
(which I'm told might break on some systems since epee is not (shouldn't be)
dependent upon the existing crypto library).
