This PR adds two optimizations to fix the optimistic lock errors observed in #1986.
First, the WFE now returns early for registration POST's (before invoking the RA and SA) when the POST body is the trivial update (`{"resource":"reg"}`). This prevents any DB operations from being performed when there is no work to be done.
Second, the RA now tracks whether a update actually changes the base registration's `Contact` slice, or `Agreement` string. If the proposed update doesn't change either of these fields then the RA will return early before handing the update to the SA.
Both changes save database operations from being performed needlessly and will help avoid the optimistic lock errors we observed when a problematic client was POSTing the trivial update repeatedly in a short period.
The fix was verified as follows: I checked out master and artificially introduced lock contention into the SA by adding a 2s sleep into `UpdateRegistration` between fetching the `existingRegModel` to get the `LockCol` value and calling `ssa.dbMap.Update`. With the sleep in place & two certbot clients posting matching registration updates the lock contention error is produced as expected. After checking out the `empty-reg-updates` branch, re-adding the sleep to the SA, and performing the same two client reg updates no error is produced.
In https://github.com/letsencrypt/boulder/pull/774 we introduced and account key stored with the challenge. This was a stopgap fix to the now-defunct SimpleHTTP and DNS challenges in the face of https://mailarchive.ietf.org/arch/msg/acme/F71iz6qq1o_QPVhJCV4dqWf-4Yc. However, we no longer offer or implement those challenges, so the extra field is unnecessary. It also take up a huge amount of space in the challenges table, which is our biggest table. SimpleHTTP and DNS challenges were removed in https://github.com/letsencrypt/boulder/pull/1247.
We can provide a follow-up migration to delete the column later, once we have a plan for large migrations without downtime.
Fixes#1909
The RA UpdateRegistration function merges a base registration object with an update by calling Registration.MergeUpdate. Prior to this commit MergeUpdate only allowed the updated registration object to overwrite the Contact field of the existing registration if the updated reg. defined at least one AcmeURL. This prevented clients from being able to outright remove the contact associated with an existing registration.
This commit removes the len() check on the input.Contact in MergeUpdate to allow the r.Contact field to be overwritten by a []*core.AcmeURL(nil) Contact field. Subsequently clients can now send an empty contacts list in the update registration POST in order to remove their reg contact.
Fixes#1846
* Allow removing registration contact.
* Adds a test for `MergeUpdate` contact removal.
* Change `Registration.Contact` type to `*[]*core.AcmeURL`.
* End validateContacts early for empty contacts
* Test removing reg. contact more thoroughly.
This is a change to ValidationRecord. This case is unlikely to be
trigged by code, but was allowing tests to pass in a branch that deleted
the simpleHttp and dvsni challenge types and is a good check to have in
place.
Updates #894
Refactor DNS problem details use
Actually store and log resolved addresses
Less convuluted get adresses function/usage
Store redirects, reconstruct transport on redirect, add redirect + lookup tests
Add another test
Review fixes
Initial bulk of review fixes (cleanups inc)
Comment cleanup
Add some more tests
Cleanups
Give addrFilter a type and add the config wiring
Expose filters
LookupHost cleanups
Remove Resolved Addresses and Redirect chain from replies to client without breaking RPC layer
Switch address/redirect logging method, add redirect loop checking + test
Review fixes + remove IPv6
Remove AddressFilter remnant + constant-ize the VA timeout
Review fixes pt. 1
Initialize validation record
Don't blank out validation reocrds
Add validation record sanity checking
Switch to shared struct
Check port is in valid range
Review fixes
Ben Irving
Daniel McCarney
Jacob Hoffman-Andrews
Roland Bracewell Shoemaker
Kane York
Jessica Frazelle
Jeff Hodges
Richard Barnes
Brad Warren
J.C. Jones