Files
nim-libp2p/libp2p/autotls/acme/api.nim
2025-07-18 11:58:27 -04:00

534 lines
17 KiB
Nim

import json, uri
from times import DateTime, parse
import chronos/apps/http/httpclient, results, chronicles
import ./utils
import ../../crypto/crypto
import ../../crypto/rsa
export ACMEError
logScope:
topics = "libp2p acme api"
const
LetsEncryptURL* = "https://acme-v02.api.letsencrypt.org"
LetsEncryptURLStaging* = "https://acme-staging-v02.api.letsencrypt.org"
Alg = "RS256"
DefaultChalCompletedRetries = 10
DefaultChalCompletedRetryTime = 1.seconds
DefaultFinalizeRetries = 10
DefaultFinalizeRetryTime = 1.seconds
DefaultRandStringSize = 256
ACMEHttpHeaders = [("Content-Type", "application/jose+json")]
type Authorization* = string
type Domain* = string
type Kid* = string
type Nonce* = string
type ACMEDirectory* = object
newNonce*: string
newOrder*: string
newAccount*: string
type ACMEApi* = ref object of RootObj
directory: Opt[ACMEDirectory]
session: HttpSessionRef
acmeServerURL*: Uri
type HTTPResponse* = object
body*: JsonNode
headers*: HttpTable
type JWK = object
kty: string
n: string
e: string
# whether the request uses Kid or not
type ACMERequestType = enum
ACMEJwkRequest
ACMEKidRequest
type ACMERequestHeader = object
alg: string
typ: string
nonce: Nonce
url: string
case kind: ACMERequestType
of ACMEJwkRequest:
jwk: JWK
of ACMEKidRequest:
kid: Kid
type Email = string
type ACMERegisterRequest* = object
termsOfServiceAgreed: bool
contact: seq[Email]
type ACMEAccountStatus = enum
valid = "valid"
deactivated = "deactivated"
revoked = "revoked"
type ACMERegisterResponseBody = object
status*: ACMEAccountStatus
type ACMERegisterResponse* = object
kid*: Kid
status*: ACMEAccountStatus
type ACMEChallengeStatus* {.pure.} = enum
PENDING = "pending"
PROCESSING = "processing"
VALID = "valid"
INVALID = "invalid"
type ACMEOrderStatus* {.pure.} = enum
PENDING = "pending"
READY = "ready"
PROCESSING = "processing"
VALID = "valid"
INVALID = "invalid"
type ACMEChallengeType* {.pure.} = enum
DNS01 = "dns-01"
HTTP01 = "http-01"
TLSALPN01 = "tls-alpn-01"
type ACMEChallengeToken* = string
type ACMEChallenge* = object
url*: string
`type`*: ACMEChallengeType
status*: ACMEChallengeStatus
token*: ACMEChallengeToken
type ACMEChallengeIdentifier = object
`type`: string
value: string
type ACMEChallengeRequest = object
identifiers: seq[ACMEChallengeIdentifier]
type ACMEChallengeResponseBody = object
status: ACMEOrderStatus
authorizations: seq[Authorization]
finalize: string
type ACMEChallengeResponse* = object
status*: ACMEOrderStatus
authorizations*: seq[Authorization]
finalize*: string
order*: string
type ACMEChallengeResponseWrapper* = object
finalize*: string
order*: string
dns01*: ACMEChallenge
type ACMEAuthorizationsResponse* = object
challenges*: seq[ACMEChallenge]
type ACMECompletedResponse* = object
url: string
type ACMECheckKind* = enum
ACMEOrderCheck
ACMEChallengeCheck
type ACMECheckResponse* = object
case kind: ACMECheckKind
of ACMEOrderCheck:
orderStatus: ACMEOrderStatus
of ACMEChallengeCheck:
chalStatus: ACMEChallengeStatus
retryAfter: Duration
type ACMEFinalizeResponse* = object
status: ACMEOrderStatus
type ACMEOrderResponse* = object
certificate: string
expires: string
type ACMECertificateResponse* = object
rawCertificate*: string
certificateExpiry*: DateTime
type ACMECertificate* = object
rawCertificate*: string
certificateExpiry*: DateTime
certKeyPair*: KeyPair
when defined(libp2p_autotls_support):
import options, sequtils, strutils, jwt, bearssl/pem
template handleError*(msg: string, body: untyped): untyped =
try:
body
except ACMEError as exc:
raise exc
except CancelledError as exc:
raise exc
except JsonKindError as exc:
raise newException(ACMEError, msg & ": Failed to decode JSON", exc)
except ValueError as exc:
raise newException(ACMEError, msg & ": Failed to decode JSON", exc)
except HttpError as exc:
raise newException(ACMEError, msg & ": Failed to connect to ACME server", exc)
except CatchableError as exc:
raise newException(ACMEError, msg & ": Unexpected error", exc)
method post*(
self: ACMEApi, uri: Uri, payload: string
): Future[HTTPResponse] {.
async: (raises: [ACMEError, HttpError, CancelledError]), base
.}
method get*(
self: ACMEApi, uri: Uri
): Future[HTTPResponse] {.
async: (raises: [ACMEError, HttpError, CancelledError]), base
.}
proc new*(
T: typedesc[ACMEApi], acmeServerURL: Uri = parseUri(LetsEncryptURL)
): ACMEApi =
let session = HttpSessionRef.new()
ACMEApi(
session: session, directory: Opt.none(ACMEDirectory), acmeServerURL: acmeServerURL
)
proc getDirectory(
self: ACMEApi
): Future[ACMEDirectory] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("getDirectory"):
self.directory.valueOr:
let acmeResponse = await self.get(self.acmeServerURL / "directory")
let directory = acmeResponse.body.to(ACMEDirectory)
self.directory = Opt.some(directory)
directory
method requestNonce*(
self: ACMEApi
): Future[Nonce] {.async: (raises: [ACMEError, CancelledError]), base.} =
handleError("requestNonce"):
let acmeResponse = await self.get(parseUri((await self.getDirectory()).newNonce))
Nonce(acmeResponse.headers.keyOrError("Replay-Nonce"))
# TODO: save n and e in account so we don't have to recalculate every time
proc acmeHeader(
self: ACMEApi, uri: Uri, key: KeyPair, needsJwk: bool, kid: Opt[Kid]
): Future[ACMERequestHeader] {.async: (raises: [ACMEError, CancelledError]).} =
if not needsJwk and kid.isNone():
raise newException(ACMEError, "kid not set")
if key.pubkey.scheme != PKScheme.RSA or key.seckey.scheme != PKScheme.RSA:
raise newException(ACMEError, "Unsupported signing key type")
let newNonce = await self.requestNonce()
if needsJwk:
let pubkey = key.pubkey.rsakey
let nArray = @(getArray(pubkey.buffer, pubkey.key.n, pubkey.key.nlen))
let eArray = @(getArray(pubkey.buffer, pubkey.key.e, pubkey.key.elen))
ACMERequestHeader(
kind: ACMEJwkRequest,
alg: Alg,
typ: "JWT",
nonce: newNonce,
url: $uri,
jwk: JWK(kty: "RSA", n: base64UrlEncode(nArray), e: base64UrlEncode(eArray)),
)
else:
ACMERequestHeader(
kind: ACMEKidRequest,
alg: Alg,
typ: "JWT",
nonce: newNonce,
url: $uri,
kid: kid.get(),
)
method post*(
self: ACMEApi, uri: Uri, payload: string
): Future[HTTPResponse] {.
async: (raises: [ACMEError, HttpError, CancelledError]), base
.} =
let rawResponse = await HttpClientRequestRef
.post(self.session, $uri, body = payload, headers = ACMEHttpHeaders)
.get()
.send()
let body = await rawResponse.getResponseBody()
HTTPResponse(body: body, headers: rawResponse.headers)
method get*(
self: ACMEApi, uri: Uri
): Future[HTTPResponse] {.
async: (raises: [ACMEError, HttpError, CancelledError]), base
.} =
let rawResponse = await HttpClientRequestRef.get(self.session, $uri).get().send()
let body = await rawResponse.getResponseBody()
HTTPResponse(body: body, headers: rawResponse.headers)
proc createSignedAcmeRequest(
self: ACMEApi,
uri: Uri,
payload: auto,
key: KeyPair,
needsJwk: bool = false,
kid: Opt[Kid] = Opt.none(Kid),
): Future[string] {.async: (raises: [ACMEError, CancelledError]).} =
if key.pubkey.scheme != PKScheme.RSA or key.seckey.scheme != PKScheme.RSA:
raise newException(ACMEError, "Unsupported signing key type")
let acmeHeader = await self.acmeHeader(uri, key, needsJwk, kid)
handleError("createSignedAcmeRequest"):
var token = toJWT(%*{"header": acmeHeader, "claims": payload})
let derPrivKey = key.seckey.rsakey.getBytes.get
let pemPrivKey: string = pemEncode(derPrivKey, "PRIVATE KEY")
token.sign(pemPrivKey)
$token.toFlattenedJson()
proc requestRegister*(
self: ACMEApi, key: KeyPair
): Future[ACMERegisterResponse] {.async: (raises: [ACMEError, CancelledError]).} =
let registerRequest = ACMERegisterRequest(termsOfServiceAgreed: true)
handleError("acmeRegister"):
let payload = await self.createSignedAcmeRequest(
parseUri((await self.getDirectory()).newAccount),
registerRequest,
key,
needsJwk = true,
)
let acmeResponse =
await self.post(parseUri((await self.getDirectory()).newAccount), payload)
let acmeResponseBody = acmeResponse.body.to(ACMERegisterResponseBody)
ACMERegisterResponse(
status: acmeResponseBody.status,
kid: acmeResponse.headers.keyOrError("location"),
)
proc requestNewOrder*(
self: ACMEApi, domains: seq[Domain], key: KeyPair, kid: Kid
): Future[ACMEChallengeResponse] {.async: (raises: [ACMEError, CancelledError]).} =
# request challenge from ACME server
let orderRequest = ACMEChallengeRequest(
identifiers: domains.mapIt(ACMEChallengeIdentifier(`type`: "dns", value: it))
)
handleError("requestNewOrder"):
let payload = await self.createSignedAcmeRequest(
parseUri((await self.getDirectory()).newOrder),
orderRequest,
key,
kid = Opt.some(kid),
)
let acmeResponse =
await self.post(parseUri((await self.getDirectory()).newOrder), payload)
let challengeResponseBody = acmeResponse.body.to(ACMEChallengeResponseBody)
if challengeResponseBody.authorizations.len == 0:
raise newException(ACMEError, "Authorizations field is empty")
ACMEChallengeResponse(
status: challengeResponseBody.status,
authorizations: challengeResponseBody.authorizations,
finalize: challengeResponseBody.finalize,
order: acmeResponse.headers.keyOrError("location"),
)
proc requestAuthorizations*(
self: ACMEApi, authorizations: seq[Authorization], key: KeyPair, kid: Kid
): Future[ACMEAuthorizationsResponse] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("requestAuthorizations"):
doAssert authorizations.len > 0
let acmeResponse = await self.get(parseUri(authorizations[0]))
acmeResponse.body.to(ACMEAuthorizationsResponse)
proc requestChallenge*(
self: ACMEApi, domains: seq[Domain], key: KeyPair, kid: Kid
): Future[ACMEChallengeResponseWrapper] {.
async: (raises: [ACMEError, CancelledError])
.} =
let orderResponse = await self.requestNewOrder(domains, key, kid)
if orderResponse.status != ACMEOrderStatus.PENDING and
orderResponse.status != ACMEOrderStatus.READY:
# ready is a valid status when renewing certs before expiry
raise
newException(ACMEError, "Invalid new order status: " & $orderResponse.status)
let authorizationsResponse =
await self.requestAuthorizations(orderResponse.authorizations, key, kid)
if authorizationsResponse.challenges.len == 0:
raise newException(ACMEError, "No challenges received")
return ACMEChallengeResponseWrapper(
finalize: orderResponse.finalize,
order: orderResponse.order,
dns01: authorizationsResponse.challenges.filterIt(
it.`type` == ACMEChallengeType.DNS01
)[0],
# getting the first element is safe since we checked that authorizationsResponse.challenges.len != 0
)
proc requestCheck*(
self: ACMEApi, checkURL: Uri, checkKind: ACMECheckKind, key: KeyPair, kid: Kid
): Future[ACMECheckResponse] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("requestCheck"):
let acmeResponse = await self.get(checkURL)
let retryAfter =
try:
parseInt(acmeResponse.headers.keyOrError("Retry-After")).seconds
except ValueError:
DefaultChalCompletedRetryTime
case checkKind
of ACMEOrderCheck:
try:
ACMECheckResponse(
kind: checkKind,
orderStatus: parseEnum[ACMEOrderStatus](acmeResponse.body["status"].getStr),
retryAfter: retryAfter,
)
except ValueError:
raise newException(
ACMEError, "Invalid order status: " & acmeResponse.body["status"].getStr
)
of ACMEChallengeCheck:
try:
ACMECheckResponse(
kind: checkKind,
chalStatus:
parseEnum[ACMEChallengeStatus](acmeResponse.body["status"].getStr),
retryAfter: retryAfter,
)
except ValueError:
raise newException(
ACMEError, "Invalid order status: " & acmeResponse.body["status"].getStr
)
proc sendChallengeCompleted*(
self: ACMEApi, chalURL: Uri, key: KeyPair, kid: Kid
): Future[ACMECompletedResponse] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("sendChallengeCompleted"):
let payload =
await self.createSignedAcmeRequest(chalURL, %*{}, key, kid = Opt.some(kid))
let acmeResponse = await self.post(chalURL, payload)
acmeResponse.body.to(ACMECompletedResponse)
proc checkChallengeCompleted*(
self: ACMEApi,
checkURL: Uri,
key: KeyPair,
kid: Kid,
retries: int = DefaultChalCompletedRetries,
): Future[bool] {.async: (raises: [ACMEError, CancelledError]).} =
for i in 0 .. retries:
let checkResponse =
await self.requestCheck(checkURL, ACMEChallengeCheck, key, kid)
case checkResponse.chalStatus
of ACMEChallengeStatus.PENDING:
await sleepAsync(checkResponse.retryAfter) # try again after some delay
of ACMEChallengeStatus.VALID:
return true
else:
raise newException(
ACMEError,
"Failed challenge completion: expected 'valid', got '" &
$checkResponse.chalStatus & "'",
)
return false
proc completeChallenge*(
self: ACMEApi,
chalURL: Uri,
key: KeyPair,
kid: Kid,
retries: int = DefaultChalCompletedRetries,
): Future[bool] {.async: (raises: [ACMEError, CancelledError]).} =
let completedResponse = await self.sendChallengeCompleted(chalURL, key, kid)
# check until acme server is done (poll validation)
return await self.checkChallengeCompleted(chalURL, key, kid, retries = retries)
proc requestFinalize*(
self: ACMEApi,
domain: Domain,
finalize: Uri,
certKeyPair: KeyPair,
key: KeyPair,
kid: Kid,
): Future[ACMEFinalizeResponse] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("requestFinalize"):
let payload = await self.createSignedAcmeRequest(
finalize, %*{"csr": createCSR(domain, certKeyPair)}, key, kid = Opt.some(kid)
)
let acmeResponse = await self.post(finalize, payload)
# server responds with updated order response
acmeResponse.body.to(ACMEFinalizeResponse)
proc checkCertFinalized*(
self: ACMEApi,
order: Uri,
key: KeyPair,
kid: Kid,
retries: int = DefaultChalCompletedRetries,
): Future[bool] {.async: (raises: [ACMEError, CancelledError]).} =
for i in 0 .. retries:
let checkResponse = await self.requestCheck(order, ACMEOrderCheck, key, kid)
case checkResponse.orderStatus
of ACMEOrderStatus.VALID:
return true
of ACMEOrderStatus.PROCESSING:
await sleepAsync(checkResponse.retryAfter) # try again after some delay
else:
error "Failed certificate finalization",
description = "expected 'valid', got '" & $checkResponse.orderStatus & "'"
return false # do not try again
return false
proc certificateFinalized*(
self: ACMEApi,
domain: Domain,
finalize: Uri,
order: Uri,
certKeyPair: KeyPair,
key: KeyPair,
kid: Kid,
retries: int = DefaultFinalizeRetries,
): Future[bool] {.async: (raises: [ACMEError, CancelledError]).} =
let finalizeResponse =
await self.requestFinalize(domain, finalize, certKeyPair, key, kid)
# keep checking order until cert is valid (done)
return await self.checkCertFinalized(order, key, kid, retries = retries)
proc requestGetOrder*(
self: ACMEApi, order: Uri
): Future[ACMEOrderResponse] {.async: (raises: [ACMEError, CancelledError]).} =
handleError("requestGetOrder"):
let acmeResponse = await self.get(order)
acmeResponse.body.to(ACMEOrderResponse)
proc downloadCertificate*(
self: ACMEApi, order: Uri
): Future[ACMECertificateResponse] {.async: (raises: [ACMEError, CancelledError]).} =
let orderResponse = await self.requestGetOrder(order)
handleError("downloadCertificate"):
let rawResponse = await HttpClientRequestRef
.get(self.session, orderResponse.certificate)
.get()
.send()
ACMECertificateResponse(
rawCertificate: bytesToString(await rawResponse.getBodyBytes()),
certificateExpiry: parse(orderResponse.expires, "yyyy-MM-dd'T'HH:mm:ss'Z'"),
)
proc close*(self: ACMEApi) {.async: (raises: [CancelledError]).} =
await self.session.closeWait()
else:
{.hint: "autotls disabled. Use -d:libp2p_autotls_support".}