JOSEVirtualHSM
Virtual JOSE HSM for signing JWSes and decrypting JWEs
Installation
def deps do
[
{:jose_virtual_hsm, "~> 0.1.0"}
]
end
Description
It is a virtual HSM in the sense that keys private keys for signing and decrypting are not available to other processes, and are particularly protected against leaking:
- there are stored in a private ETS
- processes dealing with these keys are marked as sensitive
- keys loaded from the disk or the environment can be deleted after loading (ideal for container deployment)
Other features include:
- keys can be generated automatically given a specification, so that there no secret to handle during deployment
- it is automatically clusterized: any node can sign a JWS or decrypt a JWE with any key in the cluster. Nodes don't share keys (they can't) but can work with each other in a transparent fashion
key ID is automatically generated using RFC7638 - JSON Web Key (JWK) Thumbprint
- however, note that due to a limitation in the underlying
JOSE
library, JWSes do not include the kid in their header
- however, note that due to a limitation in the underlying
Launching JOSEVirtualHSM
JOSEVirtualHSM
is a GenServer
that must be launched in a supervised manner at application
startup. In your app/application.ex
file, add:
children = [
JOSEVirtualHSM
]
or
children = [
{JOSEVirtualHSM, opts...}
]
where opts
is a Keyword
to the list of children.
Options
:delete_on_load
: when loading a private key from a file or the environment, this options, when set totrue
, deletes the key after loading. Defaults totrue
:keys
: the list of keys to load. Seet:key_load_specs/0
for the different methods to load keys
Environment options
The key specification can also be retrieved from the environment options:
config/config.exs
config :jose_virtual_hsm, :keys, [
{:auto_gen, {:ec, "P-256"}, %{"use" => "sig"}},
{:auto_gen, {:rsa, 2048}, %{"use" => "sig"}},
{:auto_gen, {:okp, :Ed25519}, %{"use" => "sig"}},
{:auto_gen, {:ec, "P-256"}, %{"use" => "enc"}},
{:auto_gen, {:rsa, 2048}, %{"use" => "enc"}},
{:auto_gen, {:okp, :X25519}, %{"use" => "enc"}}
]
This key specification is used i nthe following examples.
Example
Retrieving public keys
iex> JOSEVirtualHSM.public_keys()
[
%{
"crv" => "X25519",
"kid" => "NqYw6_wlorTvDqae3HaI79i_k_Q61l0jESQNvgT0Ku4",
"kty" => "OKP",
"use" => "enc",
"x" => "lY2nopV03NTsSqCVgfyr_VNjTBkUhGHcHjIHJNrlaKQ"
},
%{
"crv" => "Ed25519",
"kid" => "Hq3_i8UWJ1FqokUqTQRDLw4GvvBQCKiMjSoQ4Ng6CY0",
"kty" => "OKP",
"use" => "sig",
"x" => "XxHceRoVym7hsb5W-T2RqTzgoz_DEmCZKHBjy6MWsZA"
},
%{
"e" => "AQAB",
"kid" => "5A5Z3JxpYNO4pqbfC4wSFUk2cpkcAxwZsH0yev3zXpk",
"kty" => "RSA",
"n" => "7Rwb2l4ORycxCPAMK2B_p1FqKqrBpmcjklqazucAiJtNPtY2n-yEziD05-urwutIN2-wfaKIGg51-8KIQN5x_PTXUxje2oK3GOHHWaSWGpd1kJVEe-owSKGQxoga5rQDTk4j3MMA0brbgoJM2v32lKiv5CgV6E-wgCXb8QlrvIpwhnIN9CPEHuxo9Izpw8WqIj4d8Uu7LohxUM0eFfBkdbmgt5xL4Xm5MV6eDRhYq9agRLGNbBIHK2T5Xyq6-YB5URtWCeizA8hongk6nZAzy19wvz88pj4CsBy73UuP0jdT-wlGGvTpGx9AEFLv1p_RXzVgfZMGn2z3Q8Mhf0mxVQ",
"use" => "sig"
},
%{
"e" => "AQAB",
"kid" => "szhiyrpeKBtQOr6cSEj3TbJ87vqvvGuk3Is6cPBYNm0",
"kty" => "RSA",
"n" => "5GX4GERxJ2rV-w5T2G00D3-HLEriXjriL-w7TkCB9H8zhiljHH0SxmbxBMT5HksJMWQyiDZEKp6ilrZCjsvOAJCpvh0SrPnIRzu95Wt1VlGOlp0C2BnL0wuPnkrUHbGZAzE-ux4ISpw9LqTi6KlL1dWQei6-_ihs0E37iTpFJy2EbEVXG6ydsH0FnoJv0_dgf3P4Yy8kIoNx5f4czLSWhK-psoPVKxxAN3mlY7iRGQHxOdgEyrsANj8uSQehzO87T5IVmMDtoBBx6PUn9awDW5emoU_mfXy3hlR3S67pjbjfNA5A3QZBs39-hCU92EtA7CS0IQ_rvvAfvlLV3T-tjQ",
"use" => "enc"
},
%{
"crv" => "P-256",
"kid" => "ltu_BZFFssJhqlTdKvf3VWu7z9dFKhwFxXSx8Q-bpw4",
"kty" => "EC",
"use" => "enc",
"x" => "jopq4PgS4w9721MwJppxw7niV-1zqgtBd-JeVWPuBcU",
"y" => "Eo1xbm0g5AsB8GSiXKHRynXH2OwRcMO9i-6PTi-k-GE"
},
%{
"crv" => "P-256",
"kid" => "SiuAFPXstUhUzhmc__1mybX1ZJcJ6F2llEeb-LaAjIo",
"kty" => "EC",
"use" => "sig",
"x" => "2PXy4aIbWUHzkRksSITO1ws9Y1AI14fBAtsvr1UDwXQ",
"y" => "hPtgSkKH6DXzh18Ym_jh9bzcJir5mKp_skj9oKI5ydA"
}
]
These public keys can obviously be shared with third parties. They can be used:
- to verify signature of a JWS signed by
JOSEVirtualHSM
- to encrypt a JWE to be sent to the server using
JOSEVirtualHSM
JOSEVirtualHSM
doesn't support JWS verification and JWE encryption. For that, use
JOSE
or JOSEUtils
instead.
Signing:
iex> JOSEVirtualHSM.sign(%{"hello" => "world"})
{:ok,
{"eyJhbGciOiJSUzI1NiJ9.eyJoZWxsbyI6IndvcmxkIn0.nFP2GBJdsKzgUMR7g55pMmtNckXB9F9C83jhfAW0qOake7AmpZb3eLZhGi3OrTB7CRI2x9MHtA1qQMdOY0u8R_VovYfv5fGLVRJLe8uICGIq1NojO_66lMMoxmtMxIhVcX1FZfWR9Z_Ez4KGVm4eJvTuO33ds115Ik8Vh3aGFBorW74rYqjYZPgEHyjO4RqbzexBodq-z5rGOqAvFgz9C6X_xkMwiI6mNI4XIQ-5jzLPKMP5t94QwJGZ4EEc9QyFbNqmh2OlUaY0NTthP6MAzler7K5oz2S_6mQvt6K4Fmk1C-HIR3nad_s_z-PLvj6tEJnmIiEcFHTxfRcceUQ_QA",
%{
"e" => "AQAB",
"kid" => "5A5Z3JxpYNO4pqbfC4wSFUk2cpkcAxwZsH0yev3zXpk",
"kty" => "RSA",
"n" => "7Rwb2l4ORycxCPAMK2B_p1FqKqrBpmcjklqazucAiJtNPtY2n-yEziD05-urwutIN2-wfaKIGg51-8KIQN5x_PTXUxje2oK3GOHHWaSWGpd1kJVEe-owSKGQxoga5rQDTk4j3MMA0brbgoJM2v32lKiv5CgV6E-wgCXb8QlrvIpwhnIN9CPEHuxo9Izpw8WqIj4d8Uu7LohxUM0eFfBkdbmgt5xL4Xm5MV6eDRhYq9agRLGNbBIHK2T5Xyq6-YB5URtWCeizA8hongk6nZAzy19wvz88pj4CsBy73UuP0jdT-wlGGvTpGx9AEFLv1p_RXzVgfZMGn2z3Q8Mhf0mxVQ",
"use" => "sig"
}}}
iex> JOSEVirtualHSM.sign(%{"hello" => "world"})
{:ok,
{"eyJhbGciOiJFZERTQSJ9.eyJoZWxsbyI6IndvcmxkIn0.WVRgyl4Pen0nieJF7cmGXQnkOocP4B6i78VgkKxcu_-gADSIM5Cg_mL2T-cU1ZY1ib91bQnHALdNoXqVSi66DQ",
%{
"crv" => "Ed25519",
"kid" => "Hq3_i8UWJ1FqokUqTQRDLw4GvvBQCKiMjSoQ4Ng6CY0",
"kty" => "OKP",
"use" => "sig",
"x" => "XxHceRoVym7hsb5W-T2RqTzgoz_DEmCZKHBjy6MWsZA"
}}}
iex> JOSEVirtualHSM.sign(%{"hello" => "world"})
{:ok,
{"eyJhbGciOiJFZERTQSJ9.eyJoZWxsbyI6IndvcmxkIn0.WVRgyl4Pen0nieJF7cmGXQnkOocP4B6i78VgkKxcu_-gADSIM5Cg_mL2T-cU1ZY1ib91bQnHALdNoXqVSi66DQ",
%{
"crv" => "Ed25519",
"kid" => "Hq3_i8UWJ1FqokUqTQRDLw4GvvBQCKiMjSoQ4Ng6CY0",
"kty" => "OKP",
"use" => "sig",
"x" => "XxHceRoVym7hsb5W-T2RqTzgoz_DEmCZKHBjy6MWsZA"
}}}
iex> JOSEVirtualHSM.sign(%{"hello" => "world"})
{:ok,
{"eyJhbGciOiJFUzI1NiJ9.eyJoZWxsbyI6IndvcmxkIn0.1viHUsVOseF1eJ0nZAOXbo0RfHGP5H1U8lfV9qLijf4EnDbaPI7NkRdFQIHvbYVTYakm0dHdF2YPlNfKOrGMbg",
%{
"crv" => "P-256",
"kid" => "SiuAFPXstUhUzhmc__1mybX1ZJcJ6F2llEeb-LaAjIo",
"kty" => "EC",
"use" => "sig",
"x" => "2PXy4aIbWUHzkRksSITO1ws9Y1AI14fBAtsvr1UDwXQ",
"y" => "hPtgSkKH6DXzh18Ym_jh9bzcJir5mKp_skj9oKI5ydA"
}}}
Notice how keys where chosen randomly from all the available keys. JOSEVirtualHSM
always
prefers keys on local node, when available. It's possible to specify how to sign using
JOSEUtils.JWK.key_selector/0
:
iex> JOSEVirtualHSM.sign(%{"hello" => "world"}, alg: ["ES256", "ES384", "ES512"])
{:ok,
{"eyJhbGciOiJFUzI1NiJ9.eyJoZWxsbyI6IndvcmxkIn0.ooZ8pRuhp20K8s7k0xkNGCb47nE8sW_JrjHtsb_w5PEFFGR1F7wysJGfg2tTU7kT0QzQQEeWUg0FJgkqsowbTw",
%{
"crv" => "P-256",
"kid" => "SiuAFPXstUhUzhmc__1mybX1ZJcJ6F2llEeb-LaAjIo",
"kty" => "EC",
"use" => "sig",
"x" => "2PXy4aIbWUHzkRksSITO1ws9Y1AI14fBAtsvr1UDwXQ",
"y" => "hPtgSkKH6DXzh18Ym_jh9bzcJir5mKp_skj9oKI5ydA"
}}}
iex> JOSEVirtualHSM.sign(%{"hello" => "world"}, kty: "OKP")
{:ok,
{"eyJhbGciOiJFZERTQSJ9.eyJoZWxsbyI6IndvcmxkIn0.WVRgyl4Pen0nieJF7cmGXQnkOocP4B6i78VgkKxcu_-gADSIM5Cg_mL2T-cU1ZY1ib91bQnHALdNoXqVSi66DQ",
%{
"crv" => "Ed25519",
"kid" => "Hq3_i8UWJ1FqokUqTQRDLw4GvvBQCKiMjSoQ4Ng6CY0",
"kty" => "OKP",
"use" => "sig",
"x" => "XxHceRoVym7hsb5W-T2RqTzgoz_DEmCZKHBjy6MWsZA"
}}}
Decryption
With RSA:
iex> jwk_pub = JOSEVirtualHSM.public_keys() |> Enum.find(&(&1["kty"] == "RSA" and &1["use"] == "enc"))
%{
"e" => "AQAB",
"kid" => "szhiyrpeKBtQOr6cSEj3TbJ87vqvvGuk3Is6cPBYNm0",
"kty" => "RSA",
"n" => "5GX4GERxJ2rV-w5T2G00D3-HLEriXjriL-w7TkCB9H8zhiljHH0SxmbxBMT5HksJMWQyiDZEKp6ilrZCjsvOAJCpvh0SrPnIRzu95Wt1VlGOlp0C2BnL0wuPnkrUHbGZAzE-ux4ISpw9LqTi6KlL1dWQei6-_ihs0E37iTpFJy2EbEVXG6ydsH0FnoJv0_dgf3P4Yy8kIoNx5f4czLSWhK-psoPVKxxAN3mlY7iRGQHxOdgEyrsANj8uSQehzO87T5IVmMDtoBBx6PUn9awDW5emoU_mfXy3hlR3S67pjbjfNA5A3QZBs39-hCU92EtA7CS0IQ_rvvAfvlLV3T-tjQ",
"use" => "enc"
}
iex> jwe = JOSEUtils.JWE.encrypt!(%{"very" => "secret"}, jwk_pub, "RSA-OAEP", "A128GCM")
"eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkExMjhHQ00ifQ.0odG-8i5DL-SB1h4_DeGbavEZhACbVKqvnz2MCoSUyCW84U7ejqn2HqLh8Te03_yIlR9jC8raJ4OI75fbsK9bKrSf_RubJIYjVto0GaBIJzREujjS2fVACe5UUPQ9lVkYplXiT-wqm3wvtX9GkaBz4FL-fmftgtdW9zdYC9U2D_AfFG5hhO4BnAUaI7x1wDdnVMCPjbg5B21x6IPGSma0H6YgCyBf26BRIuNNRbaly89CAam3oqzTn3t0UrDb-Hrx8jEC4a9RxmL44RIdFVAjijcWLjorSd8qq8qGrDa7gpcFEGAYrX7U5XDawjyJnWzWD1g-LDn6H0IbAn5LEorEA.rTMjuaYevaacZbzt.6t7IpuvqFe2nt94httLzpjk.Cc5UcgwZBhkuUFsDeKpQBA"
iex> JOSEVirtualHSM.decrypt(jwe)
{:ok,
{"{\\"very\\":\\"secret\\"}",
%{
"e" => "AQAB",
"kid" => "szhiyrpeKBtQOr6cSEj3TbJ87vqvvGuk3Is6cPBYNm0",
"kty" => "RSA",
"n" => "5GX4GERxJ2rV-w5T2G00D3-HLEriXjriL-w7TkCB9H8zhiljHH0SxmbxBMT5HksJMWQyiDZEKp6ilrZCjsvOAJCpvh0SrPnIRzu95Wt1VlGOlp0C2BnL0wuPnkrUHbGZAzE-ux4ISpw9LqTi6KlL1dWQei6-_ihs0E37iTpFJy2EbEVXG6ydsH0FnoJv0_dgf3P4Yy8kIoNx5f4czLSWhK-psoPVKxxAN3mlY7iRGQHxOdgEyrsANj8uSQehzO87T5IVmMDtoBBx6PUn9awDW5emoU_mfXy3hlR3S67pjbjfNA5A3QZBs39-hCU92EtA7CS0IQ_rvvAfvlLV3T-tjQ",
"use" => "enc"
}}}
With ECDH-ES:
iex> jwk_pub = JOSEVirtualHSM.public_keys() |> Enum.find(&(&1["kty"] == "EC" and &1["use"] == "enc"))
%{
"crv" => "P-256",
"kid" => "ltu_BZFFssJhqlTdKvf3VWu7z9dFKhwFxXSx8Q-bpw4",
"kty" => "EC",
"use" => "enc",
"x" => "jopq4PgS4w9721MwJppxw7niV-1zqgtBd-JeVWPuBcU",
"y" => "Eo1xbm0g5AsB8GSiXKHRynXH2OwRcMO9i-6PTi-k-GE"
}
iex> my_jwk_priv = JOSE.JWK.generate_key({:ec, "P-256"}) |> JOSE.JWK.to_map() |> elem(1)
%{
"crv" => "P-256",
"d" => "TsfNgJq_UEWdf0rqp2W5OQJQMbtANMMWwguNO4VrZkM",
"kty" => "EC",
"x" => "UIZ5br7q2li5NzcZePOiK4Wi3jV4xATVT4Yie8xMRT8",
"y" => "eiLF2EUWFbPX2MTchz_h-VbiEjnJ9koB-6kVqWF3kBo"
}
iex> jwe = JOSEUtils.JWE.encrypt!(%{"very" => "secret"}, {jwk_pub, my_jwk_priv}, "ECDH-ES", "A128GCM")
"eyJhbGciOiJFQ0RILUVTIiwiZW5jIjoiQTEyOEdDTSIsImVwayI6eyJjcnYiOiJQLTI1NiIsImt0eSI6IkVDIiwieCI6IlVJWjVicjdxMmxpNU56Y1plUE9pSzRXaTNqVjR4QVRWVDRZaWU4eE1SVDgiLCJ5IjoiZWlMRjJFVVdGYlBYMk1UY2h6X2gtVmJpRWpuSjlrb0ItNmtWcVdGM2tCbyJ9fQ..16AhXI2qu9cw7A6e.dG_TaBdpAJHgR962LxThdWo.uBtZ3N55sztIRgCFwzC5hw"
iex> JOSEVirtualHSM.decrypt(jwe)
{:ok,
{"{\\"very\\":\\"secret\\"}",
%{
"crv" => "P-256",
"kid" => "ltu_BZFFssJhqlTdKvf3VWu7z9dFKhwFxXSx8Q-bpw4",
"kty" => "EC",
"use" => "enc",
"x" => "jopq4PgS4w9721MwJppxw7niV-1zqgtBd-JeVWPuBcU",
"y" => "Eo1xbm0g5AsB8GSiXKHRynXH2OwRcMO9i-6PTi-k-GE"
}}}
Clustering
The JOSEVirtualHSM
of the current node listens to other JOSEVirtualHSM
on joining and
leaving of other nodes, and registers their public keys and deletes them when needed.
This is based on BEAM distribution. Other distribution methods (such as using Redis as an intermediary) are not supported.
Architecture
Each node runs its own instance of JOSEVirtualHSM
, which is a GenServer
. This
GenServer
has the following roles:
- on startup, it loads the keys from the key specification
- it stores local private keys in a private ETS
- it listens for joining and leaving nodes to gain knowledge of available keys
When an operation is requested for a local key, the local instance of JOSEVirtualHSM
launches a worker process and sends it the required private keys to perform the signing or
decryption operation. This process is in charge of:
- performing the signing or decryption operation
- answer to the original process
The JOSEVirtualHSM
instance keeps track of the launched process and responds with an error
to the calling process if the worker process died in an abnormal manner.
The number of worker processes is not limited. No queueing or pooling method is implemented. As a consequence, a server could become unresponsive and overwhelmed should too many signing or decryption requests arrive at the same time. Any PR implementing it is welcome :)