Commit Graph

56 Commits

Author SHA1 Message Date
Roland Bracewell Shoemaker 842739bccd Remove deprecated features that have been purged from prod and staging configs (#4001) 2019-01-15 16:16:35 -08:00
Daniel McCarney 52395a061a WFE2: Remove ACME13KeyRollover feature and legacy code. (#3999)
The draft 13 ACME v2 key change behaviour is now mandatory and we can remove the legacy WFE2 code.
2019-01-15 15:40:01 -08:00
Daniel McCarney b0f407dcf0 RA: Remove deprecated UpdateAuthorization RPC. (#3993)
Staging and prod both deployed the PerformValidationRPC feature flag. All running WFE/WFE2 instances are using the more accurately named PerformValidation RPC and we can strip out the old UpdateAuthorization bits. The feature flag for PerformValidationRPC remains until we clean up the staging/prod configs.

Resolves #3947 and completes the last of #3930
2019-01-07 16:35:27 -08:00
Daniel McCarney e5b8d530b7
wfe2: Return Status 200 for HEAD to new-nonce endpoint. (#3992)
Previously we mistakenly returned status 204 (no content) for all
requests to new-nonce, including HEAD. This status should only be used
for GET requests.

When the `HeadNonceStatusOK` feature flag is enabled we will now return
the correct status for HEAD requests. When the flag is disabled we return
status 204 to preserve backwards compatibility.
2019-01-07 12:58:30 -05:00
Daniel McCarney 8f5de538c1
RA: Add PerformValidation RPC to replace UpdateAuthorization. (#3942)
The existing RA `UpdateAuthorization` RPC needs replacing for
two reasons:

1. The name isn't accurate - `PerformValidation` better captures
the purpose of the RPC.
2. The `core.Challenge` argument is superfluous since Key 
Authorizations are not sent in the initiation POST from the client 
anymore. The corresponding unmarshal and verification is now 
removed. Notably this means broken clients that were POSTing
the wrong thing and failing pre-validation will now likely fail 
post-validation.

To remove `UpdateAuthorization` the new `PerformValidation` 
RPC is added alongside the old one. WFE and WFE2 are 
updated to use the new RPC when the perform validation
feature flag is enabled. We can remove 
`UpdateAuthorization` and its associated wrappers once all 
WFE instances have been updated.

Resolves https://github.com/letsencrypt/boulder/issues/3930
2018-11-28 10:12:47 -05:00
Daniel McCarney d9d2f4e9b0
VA: Simplified HTTP-01 w/ IP address URLs (#3939)
Continued bugs from the custom dialer approach used by the VA for HTTP-01 (most recently https://github.com/letsencrypt/boulder/issues/3889) motivated a rewrite.

Instead of using a custom dialer to be able to control DNS resolution for HTTP validation requests we can construct URLs for the IP addresses we resolve and overload the Host header. This avoids having to do address resolution within the dialer and eliminates the complexity of the dialer `addrInfoChan`. The only thing left for our custom dialer now is to shave some time off of the provided context to help us discern timeouts before/after connect.

The existing IP preference & fallback behaviour is preserved: e.g. if a host has both IPv6 and IPv4 addresses we connect to the first IPv6 address. If there is a network error connecting to that address (e.g. an error during "dial"), we try once more with the first IPv4 address. No other retries are done. Matching existing behaviour no fallback is done for HTTP level failures on an IPv6 address (e.g. mismatched webroots, redirect loops, etc). A new Prometheus counter "http01_fallbacks" is used to keep track of the number of fallbacks performed.

As a result of moving the layer at which the retry happens a fallback like described above will now produce two validation records: one for the initial IPv6 connection, and one for the IPv4 connection. Neither will have the "addressesTried" field populated, just "addressesResolved" and "addressUsed". Previously with the dialer doing the retry we would have created just one validation record with an IPv4 "addressUsed" field and both an IPv6 and IPv4 address in the "addressesTried" field.

Because this is a big diff for a key part of the VA the new code is gated by the `SimplifiedVAHTTP` feature flag.

Resolves #3889
2018-11-19 14:15:39 -05:00
Roland Bracewell Shoemaker a9a0846ee9
Remove checks for deployed features (#3881)
Removes the checks for a handful of deployed feature flags in preparation for removing the flags entirely. Also moves all of the currently deprecated flags to a separate section of the flags list so they can be more easily removed once purged from production configs.

Fixes #3880.
2018-10-17 20:29:18 -07:00
Roland Bracewell Shoemaker 484fd31460 Probe logs from inside the publisher (#3873)
Does a simpler probe than compared to using a `blackbox_exporter`, but directly collects the info we think will aid debugging publisher outages.

Updates #3821.
2018-09-27 14:42:26 -04:00
Daniel McCarney 0cb28c9e02
WFE2: Implement draft-13 keyrollover with feature flag. (#3813)
ACME draft-13 changed the inner JWS' body to contain the old key
that signed the outer JWS. Because this is a backwards incompatible
change with the draft-12 ACME v2 key rollover we introduce a new feature
flag `features.ACME13KeyRollover` and conditionally use the old or new
key rollover semantics based on its value.
2018-08-07 15:27:25 -04:00
Daniel McCarney bbf0102cdc
Remove UseAIAIssuerURL feature flag and code. (#3790)
We aren't going to deploy this as-is and its causing integration test
problems for downstream clients.
2018-07-03 16:29:44 -04:00
Joel Sing 9c2859c87b Add support for CAA account-uri validation. (#3736)
This adds support for the account-uri CAA parameter as specified by
section 3 of https://tools.ietf.org/html/draft-ietf-acme-caa-04, allowing
issuance to be restricted to one or more ACME accounts as specified by CAA
records.
2018-06-08 12:08:03 -07:00
Joel Sing 2540d59296 Implement CAA validation-methods checking. (#3716)
When performing CAA checking respect the validation-methods parameter (if
present) and restrict the allowed authorization methods to those specified.
This allows a domain to restrict authorization methods that can be used with
Let's Encrypt.

This is largely based on PR #3003 (by @lukaslihotzki), which was landed and
then later reverted due to issue #3143. The bug the resulted in the previous
code being reverted has been addressed (likely inadvertently) by 76973d0f.

This implementation also includes integration tests for CAA validation-methods.

Fixes issue #3143.
2018-05-23 14:32:31 -07:00
Daniel ac6672bc71
Revert "Revert "V2: implement "ready" status for Order objects (#3614)" (#3643)"
This reverts commit 3ecf841a3a.
2018-04-12 13:20:47 -04:00
Jacob Hoffman-Andrews 3ecf841a3a Revert "V2: implement "ready" status for Order objects (#3614)" (#3643)
This reverts commit 1d22f47fa2.

According to
https://github.com/letsencrypt/boulder/pull/3614#issuecomment-380615172,
this broke Certbot's tests. We'll investigate, and then roll forward
once we understand what broke.
2018-04-12 10:46:57 -04:00
Daniel McCarney 1d22f47fa2 V2: implement "ready" status for Order objects (#3614)
* SA: Add Order "Ready" status, feature flag.

This commit adds the new "Ready" status to `core/objects.go` and updates
`sa.statusForOrder` to use it conditionally for orders with all valid
authorizations that haven't been finalized yet. This state is used
conditionally based on the `features.OrderReadyStatus` feature flag
since it will likely break some existing clients that expect status
"Processing" for this state. The SA unit test for `statusForOrder` is
updated with a "ready" status test case.

* RA: Enforce order ready status conditionally.

This commit updates the RA to conditionally expect orders that are being
finalized to be in the "ready" status instead of "pending". This is
conditionally enforced based on the `OrderReadyStatus` feature flag.
Along the way the SA was changed to calculate the order status for the
order returned in `sa.NewOrder` dynamically now that it could be
something other than "pending".

* WFE2: Conditionally enforce order ready status for finalization.

Similar to the RA the WFE2 should conditionally enforce that an order's
status is either "ready" or "pending" based on the "OrderReadyStatus"
feature flag.

* Integration: Fix `test_order_finalize_early`.

This commit updates the V2 `test_order_finalize_early` test for the
"ready" status. A nice side-effect of the ready state change is that we
no longer invalidate an order when it is finalized too soon because we
can reject the finalization in the WFE. Subsequently the
`test_order_finalize_early` testcase is also smaller.

* Integration: Test classic behaviour w/o feature flag.

In the previous commit I fixed the integration test for the
`config/test-next` run that has the `OrderReadyStatus` feature flag set
but broke it for the `config/test` run without the feature flag.

This commit updates the `test_order_finalize_early` test to work
correctly based on the feature flag status in both cases.
2018-04-11 10:31:25 -07:00
Jacob Hoffman-Andrews a4f9de9e35 Improve nesting of RPC deadlines (#3619)
gRPC passes deadline information through the RPC boundary, but client and server have the same deadline. Ideally we'd like the server to have a slightly tighter deadline than the client, so if one of the server's onward RPCs or other network calls times out, the server can pass back more detailed information to the client, rather than the client timing out the server and losing the opportunity to log more detailed information about which component caused the timeout.

In this change, I subtract 100ms from the deadline on the server side of our interceptors, using our existing serverInterceptor. I also check that there is at least 100ms remaining in which to do useful work, so the server doesn't begin a potentially expensive task only to abort it.

Fixes #3608.
2018-04-06 15:40:18 +01:00
Jacob Hoffman-Andrews 700604dda1
Overlapping wildcard errors are 400, not 500. (#3561)
Return a malformed error for these requests. Also add an integration test.

Fixes #3558
2018-03-14 13:18:25 -07:00
Roland Bracewell Shoemaker 9c9e944759 Add SCT embedding (#3521)
Adds SCT embedding to the certificate issuance flow. When a issuance is requested a precertificate (the requested certificate but poisoned with the critical CT extension) is issued and submitted to the required CT logs. Once the SCTs for the precertificate have been collected a new certificate is issued with the poison extension replace with a SCT list extension containing the retrieved SCTs.

Fixes #2244, fixes #3492 and fixes #3429.
2018-03-12 11:58:30 -07:00
Jacob Hoffman-Andrews 78379bfced Force challenge status to be equal to authz status (#3541)
This is in general the case, but occasionally when there are two inflight validations for
a challenge at once, the authz can get marked invalid while leaving the challenge
"pending". For clients that poll the challenge instead of the authz this can lead to infinite
polling. To stop those clients, we just ensure the challenge status is consistent with its
authorization object.

Fixes #3493.
2018-03-10 07:06:27 +00:00
Jacob Hoffman-Andrews 11434650b7 Check safe browsing at validation time (#3539)
Right now we check safe browsing at new-authz time, which introduces a possible
external dependency when calling new-authz. This is usually fine, since most safe
browsing checks can be satisfied locally, but when requests have to go external,
it can create variance in new-authz timing.

Fixes #3491.
2018-03-09 11:15:05 +00:00
Daniel McCarney 3062662aad ACMEv2: Enforce POST Content-Type (when feature on) (#3532)
This commit adds a new WFE2 feature flag "EnforceV2ContentType". When
enabled, the WFE2's validPostRequest function will enforce that the
request carries a Content-Type header equal to
application/jose+json. This is required by ACME draft-10 per section
6.2 "Request Authentication".

This is behind a feature flag because it is likely to break
some number of existing ACMEv2 clients that may not be sending the
correct Content-Type.

We are defaulting to not setting the new feature flag in test/config-next
because it currently break's Certbot's acme module's revocation support
and we rely on this in our V2 integration tests.

Resolves #3529
2018-03-08 18:19:53 +00:00
Daniel McCarney 28cc969814 Remove TLS-SNI-02 implementation. (#3516)
This code was never enabled in production. Our original intent was to
ship this as part of the ACMEv2 API. Before that could happen flaws were
identified in TLS-SNI-01|02 that resulted in TLS-SNI-02 being removed
from the ACME protocol. We won't ever be enabling this code and so we
might as well remove it.
2018-03-02 10:56:13 -08:00
Roland Bracewell Shoemaker 0b53063a72 ctpolicy: Add informational logs and don't cancel remaining submissions (#3472)
Add a set of logs which will be submitted to but not relied on for their SCTs,
this allows us to test submissions to a particular log or submit to a log which
is not yet approved by a browser/root program.

Also add a feature which stops cancellations of remaining submissions when racing
to get a SCT from a group of logs.

Additionally add an informational log that always times out in config-next.

Fixes #3464 and fixes #3465.
2018-02-23 21:51:50 -05:00
Roland Bracewell Shoemaker fc5c8f76b6 Remove unused features (#3393)
This removes a number of unused features (i.e. they are never checked anywhere).
2018-01-25 08:55:05 -05:00
Jacob Hoffman-Andrews 8153b919be
Implement TLSSNIRevalidation (#3361)
This change adds a feature flag, TLSSNIRevalidation. When it is enabled, Boulder
will create new authorization objects with TLS-SNI challenges if the requesting
account has issued a certificate with the relevant domain name, and was the most
recent account to do so*. This setting overrides the configured list of
challenges in the PolicyAuthority, so even if TLS-SNI is disabled in general, it
will be enabled for revalidation.

Note that this interacts with EnforceChallengeDisable. Because
EnforceChallengeDisable causes additional checked at validation time and at
issuance time, we need to update those two places as well. We'll send a
follow-up PR with that.

*We chose to make this work only for the most recent account to issue, even if
there were overlapping certificates, because it significantly simplifies the
database access patterns and should work for 95+% of cases.

Note that this change will let an account revalidate and reissue for a domain
even if the previous issuance on that account used http-01 or dns-01. This also
simplifies implementation, and fits within the intent of the mitigation plan: If
someone previously issued for a domain using http-01, we have high confidence
that they are actually the owner, and they are not going to "steal" the domain
from themselves using tls-sni-01.

Also note: This change also doesn't work properly with ReusePendingAuthz: true.
Specifically, if you attempted issuance in the last couple days and failed
because there was no tls-sni challenge, you'll still have an http-01 challenge
lying around, and we'll reuse that; then your client will fail due to lack of
tls-sni challenge again.

This change was joint work between @rolandshoemaker and @jsha.
2018-01-12 11:00:06 -08:00
Roland Shoemaker d07092baf5 Satisfy travis 2018-01-09 21:06:41 -08:00
Roland Shoemaker 1a3a76438c Fix tests and GetOrderAuthorizations 2018-01-09 20:38:52 -08:00
Jacob Hoffman-Andrews af0bd70196
Update boulder-tools version. (#3294)
Also update chisel.py to refer to josepy, and update featureflag_string.go based on latest stringer.

Fixes #3289
2017-12-21 10:36:04 -08:00
Daniel McCarney 1c99f91733 Policy based issuance for wildcard identifiers (Round two) (#3252)
This PR implements issuance for wildcard names in the V2 order flow. By policy, pending authorizations for wildcard names only receive a DNS-01 challenge for the base domain. We do not re-use authorizations for the base domain that do not come from a previous wildcard issuance (e.g. a normal authorization for example.com turned valid by way of a DNS-01 challenge will not be reused for a *.example.com order).

The wildcard prefix is stripped off of the authorization identifier value in two places:

When presenting the authorization to the user - ACME forbids having a wildcard character in an authorization identifier.
When performing validation - We validate the base domain name without the *. prefix.
This PR is largely a rewrite/extension of #3231. Instead of using a pseudo-challenge-type (DNS-01-Wildcard) to indicate an authorization & identifier correspond to the base name of a wildcard order name we instead allow the identifier to take the wildcard order name with the *. prefix.
2017-12-04 12:18:10 -08:00
Jacob Hoffman-Andrews 2fd2f9e230 Remove LegacyCAA implementation. (#3240)
Fixes #3236
2017-11-20 16:09:00 -05:00
Jacob Hoffman-Andrews 5df083a57e Add ROCA weak key checking (#3189)
Thanks to @titanous for the library!
2017-11-02 08:42:59 -04:00
Jacob Hoffman-Andrews 4e68fb2ff6 Switch to udp for internal DNS. (#3135)
We used to use TCP because we would request DNSSEC records from Unbound, and
they would always cause truncated records when present. Now that we no longer
request those (#2718), we can use UDP. This is better because the TCP serving
paths in Unbound are likely less thoroughly tested, and not optimized for high
load. In particular this may resolve some availability problems we've seen
recently when trying to upgrade to a more recent Unbound.

Note that this only affects the Boulder->Unbound path. The Unbound->upstream
path is already UDP by default (with TCP fallback for truncated ANSWERs).
2017-10-10 10:06:33 -04:00
Daniel McCarney 1794c56eb8 Revert "Add CAA parameter to restrict challenge type (#3003)" (#3145)
This reverts commit 23e2c4a836.
2017-10-04 12:00:44 -07:00
lukaslihotzki 23e2c4a836 Add CAA parameter to restrict challenge type (#3003)
This commit adds CAA `issue` paramter parsing and the `challenge` parameter to permit a single challenge type only. By setting `challenge=dns-01`, the nameserver keeps control over every issued certificate.
2017-10-02 11:59:47 -07:00
Jacob Hoffman-Andrews 4266853092 Implement legacy form of CAA (#3075)
This implements the pre-erratum 5065 version of CAA, behind a feature flag.

This involved refactoring DNSClient.LookupCAA to return a list of CNAMEs in addition to the CAA records, and adding an alternate lookuper that does tree-climbing on single-depth aliases.
2017-09-13 10:16:12 -04:00
Jacob Hoffman-Andrews b0c7bc1bee Recheck CAA for authorizations older than 8 hours (#3014)
Fixes #2889.

VA now implements two gRPC services: VA and CAA. These both run on the same port, but this allows implementation of the IsCAAValid RPC to skip using the gRPC wrappers, and makes it easier to potentially separate the service into its own package in the future.

RA.NewCertificate now checks the expiration times of authorizations, and will call out to VA to recheck CAA for those authorizations that were not validated recently enough.
2017-08-28 16:40:57 -07:00
Kleber Correia 338c61171b Remove IDNASupport flag (#2926)
Splitting #2712 into multiple per-flag PRs
2017-08-01 16:51:19 -07:00
Daniel McCarney 57252c3b07 Remove letsencrypt/go-safe-browsing-api dependency. (#2905)
We have migrated from our fork of `go-safe-browsing-api` to Google's
safebrowsing v4 library. This commit removes the legacy safe browsing
code.
2017-07-26 13:57:57 -07:00
Daniel McCarney 71f8ae0e87 Improve renewal rate limiting (#2832)
As described in Boulder issue #2800 the implementation of the SA's
`countCertificates` function meant that the renewal exemption for the
Certificates Per Domain rate limit was difficult to work with. To
maximize allotted certificates clients were required to perform all new
issuances first, followed by the "free" renewals. This arrangement was
difficult to coordinate.

In this PR `countCertificates` is updated such that renewals are
excluded from the count reliably. To do so the SA takes the serials it
finds for a given domain from the issuedNames table and cross references
them with the FQDN sets it can find for the associated serials. With the
FQDN sets a second query is done to find all the non-renewal FQDN sets
for the serials, giving a count of the total non-renewal issuances to
use for rate limiting.

Resolves #2800
2017-06-27 15:39:59 -04:00
Jacob Hoffman-Andrews d47d3c5066 Recycle pending authorizations (#2797)
If the feature flag "ReusePendingAuthz" is enabled, a request to create a new authorization object from an account that already has a pending authorization object for the same identifier will return the already-existing authorization object. This should make it less common for people to get stuck in the "too many pending authorizations" state, and reduce DB storage growth.

Fixes #2768
2017-06-19 13:35:36 -04:00
Daniel 8c547473b8
Adds "meta" entry w/ ToS to /directory.
This commit adds the acme draft-02+ optional "meta" element for the
/directory response. Presently we only include the optional
"terms-of-service" URL. Whether the meta entry is included is controlled
by two factors:

  1. The state of the "DirectoryMeta" feature flag, which defaults to
     off
  2. Whether the client advertises the UA we know to be intolerant of
     new directory entries.

The TestDirectory unit test is updated to test both states of the flag
and the UA detection.
2017-05-09 15:43:16 -04:00
Roland Bracewell Shoemaker 730318a755 Add GREASE to directory (#2731)
Randomly generates and adds a key to the directory object with the value grease.

Fixes #2415.
2017-05-08 14:13:35 -07:00
Daniel McCarney 47452d6c6c Prefer IPv6 addresses, fall back to IPv4. (#2715)
This PR introduces a new feature flag "IPv6First". 

When the "IPv6First" feature is enabled the VA's HTTP dialer and TLS SNI
(01 and 02) certificate fetch requests will attempt to automatically
retry when the initial connection was to IPv6 and there is an IPv4
address available to retry with.

This resolves https://github.com/letsencrypt/boulder/issues/2623
2017-05-08 13:00:16 -07:00
Daniel McCarney 1ed34a4a5d Fixes cert count rate limit for exact PSL matches. (#2703)
Prior to this PR if a domain was an exact match to a public suffix
list entry the certificates per name rate limit was applied based on the
count of certificates issued for that exact name and all of its
subdomains.

This PR introduces an exception such that exact public suffix
matches correctly have the certificate per name rate limit applied based
on only exact name matches.

In order to accomplish this a new RPC is added to the SA
`CountCertificatesByExactNames`. This operates similar to the existing
`CountCertificatesByNames` but does *not* include subdomains in the
count, only exact matches to the names provided. The usage of this new
RPC is feature flag gated behind the "CountCertificatesExact" feature flag.

The RA unit tests are updated to test the new code paths both with and
without the feature flag enabled.

Resolves #2681
2017-05-02 13:43:35 -07:00
Roland Bracewell Shoemaker fd561ef842 Block issuance on first OCSP response generation (#2633)
Generate first OCSP response in ca.IssueCertificate instead of ocsp-updater.newCertificateTick
if features.GenerateOCSPEarly is enabled. Adds a new field to the sa.AddCertiifcate RPC for
the OCSP response and only adds it to the certificate status + sets ocspLastUpdated if it is a
non-empty slice. ocsp-updater.newCertificateTick stays the same so we can catch certificates
that were successfully signed + stored but a OCSP response couldn't be generated (for whatever
reason).

Fixes #2477.
2017-04-04 11:28:09 -07:00
Roland Bracewell Shoemaker 08f4dda038 Update github.com/grpc-ecosystem/go-grpc-prometheus and google.golang.org/grpc (#2637)
Updates the various gRPC/protobuf libs (google.golang.org/grpc/... and github.com/golang/protobuf/proto) and the boulder-tools image so that we can update to the newest github.com/grpc-ecosystem/go-grpc-prometheus. Also regenerates all of the protobuf definition files.

Tests run on updated packages all pass.

Unblocks #2633 fixes #2636.
2017-04-03 11:13:48 -07:00
David Calavera c71c3cff80 Implement TLS-SNI-02 challenge validations. (#2585)
I think these are all the necessary changes to implement TLS-SNI-02 validations, according to the section 7.3 of draft 05:

https://tools.ietf.org/html/draft-ietf-acme-acme-05#section-7.3

I don't have much experience with this code, I'll really appreciate your feedback.

Signed-off-by: David Calavera <david.calavera@gmail.com>
2017-03-22 10:17:59 -07:00
Daniel McCarney fcf361c327 Remove CertStatusOptimizationsMigrated Feature Flag & Assoc. Cruft (#2561)
The NotAfter and IsExpired fields on the certificateStatus table
have been migrated in staging & production. Similarly the
CertStatusOptimizationsMigrated feature flag has been turned on after
a successful backfill operation. We have confirmed the optimization is
working as expected and can now clean out the duplicated v1 and v2
models, and the feature flag branching. The notafter-backfill command
is no longer useful and so this commit also cleans it out of the repo.

Note: Some unit tests were sidestepping the SA and inserting
certificateStatus rows explicitly. These tests had to be updated to
set the NotAfter field in order for the queries used by the
ocsp-updater and the expiration-mailer to perform the way the tests
originally expected.

Resolves #2530
2017-02-16 11:35:00 -08:00
Patrick Figel 6ba8aadfd7 Use X.509 AIA Issuer URL in rel="up" link header (#2545)
In order to provide the correct issuer certificate for older certificates after an issuer certificate rollover or when using multiple issuer certificates (e.g. RSA and ECDSA), use the AIA CA Issuer URL embedded in the certificate for the rel="up" link served by WFE. This behaviour is gated behind the UseAIAIssuerURL feature, which defaults to false.

To prevent MitM vulnerabilities in cases where the AIA URL is HTTP-only, it is upgraded to HTTPS.

This also adds a test for the issuer URL returned by the /acme/cert endpoint. wfe/test/178.{crt,key} were regenerated to add the AIA extension required to pass the test.

/acme/cert was changed to return an absolute URL to the issuer endpoint (making it consistent with /acme/new-cert).

Fixes #1663
Based on #1780
2017-02-07 11:19:22 -08:00
Daniel McCarney 74e281c1ce Switch to Google's v4 safebrowsing library. (#2446)
Right now we are using a third-party client for the Google Safe Browsing API, but Google has recently released their own [Golang library](https://github.com/google/safebrowsing) which also supports the newer v4 API. Using this library will let us avoid fixing some lingering race conditions & unpleasantness in our fork of `go-safebrowsing-api`.

This PR adds support for using the Google library & the v4 API in place of our existing fork when the `GoogleSafeBrowsingV4` feature flag is enabled in the VA "features" configuration.

Resolves https://github.com/letsencrypt/boulder/issues/1863

Per `CONTRIBUTING.md` I also ran the unit tests for the new dependency:
```
daniel@XXXXXXXXXX:~/go/src/github.com/google/safebrowsing$ go test ./...
ok  	github.com/google/safebrowsing	3.274s
?   	github.com/google/safebrowsing/cmd/sblookup	[no test files]
?   	github.com/google/safebrowsing/cmd/sbserver	[no test files]
?   	github.com/google/safebrowsing/cmd/sbserver/statik	[no test files]
?   	github.com/google/safebrowsing/internal/safebrowsing_proto	[no test files]
ok  	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/jsonpb	0.012s
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/jsonpb/jsonpb_test_proto	[no test files]
ok  	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/proto	0.062s
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/proto/proto3_proto	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/protoc-gen-go	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/protoc-gen-go/descriptor	[no test files]
ok  	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/protoc-gen-go/generator	0.017s
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/protoc-gen-go/grpc	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/protoc-gen-go/plugin	[no test files]
ok  	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes	0.009s
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/any	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/duration	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/empty	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/struct	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/timestamp	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/golang/protobuf/ptypes/wrappers	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/rakyll/statik	[no test files]
?   	github.com/google/safebrowsing/vendor/github.com/rakyll/statik/fs	[no test files]
ok  	github.com/google/safebrowsing/vendor/golang.org/x/net/idna	0.003s
```
2016-12-27 11:18:11 -05:00