if requesting a tls certificate through acme fails, put any validation error messages provided by the acme server in the error message

so users can understand what is going on. e.g. a CAA record that doesn't allow
a CA to sign a certificate. previously, the error message would just be "no
viable challenge type found", which doesn't help the user.

go.mod

@@ -4,7 +4,7 @@ go 1.20
 
 require (
 	github.com/mjl-/adns v0.0.0-20231009145311-e3834995f16c
-	github.com/mjl-/autocert v0.0.0-20231009155929-d0d48f2f0290
+	github.com/mjl-/autocert v0.0.0-20231013072455-c361ae2e20a6
 	github.com/mjl-/bstore v0.0.2
 	github.com/mjl-/sconf v0.0.5
 	github.com/mjl-/sherpa v0.6.6

go.sum

@@ -149,6 +149,8 @@ github.com/mjl-/adns v0.0.0-20231009145311-e3834995f16c h1:ZOr9KnCxfAwJWSeZn8Qs6
 github.com/mjl-/adns v0.0.0-20231009145311-e3834995f16c/go.mod h1:JWhGACVviyVUEra9Zv1M8JMkDVXArVt+AIXjTXtuwb4=
 github.com/mjl-/autocert v0.0.0-20231009155929-d0d48f2f0290 h1:0hCRSu8+XCZ2cSRW+ZtP/7L5wMYjOKFSQthoyj+4cN8=
 github.com/mjl-/autocert v0.0.0-20231009155929-d0d48f2f0290/go.mod h1:taMFU86abMxKLPV4Bynhv8enbYmS67b8LG80qZv2Qus=
+github.com/mjl-/autocert v0.0.0-20231013072455-c361ae2e20a6 h1:TEXyTghAN9pmV2ffzdnhmzkML08e1Z/oGywJ9eunbRI=
+github.com/mjl-/autocert v0.0.0-20231013072455-c361ae2e20a6/go.mod h1:taMFU86abMxKLPV4Bynhv8enbYmS67b8LG80qZv2Qus=
 github.com/mjl-/bstore v0.0.2 h1:4fdpIOY/+Dv1dBHyzdqa4PD90p8Mz86FeyRpI4qcehw=
 github.com/mjl-/bstore v0.0.2/go.mod h1:/cD25FNBaDfvL/plFRxI3Ba3E+wcB0XVOS8nJDqndg0=
 github.com/mjl-/sconf v0.0.5 h1:4CMUTENpSnaeP2g6RKtrs8udTxnJgjX2MCCovxGId6s=

vendor/github.com/mjl-/autocert/autocert.go

@@ -725,6 +725,7 @@ func (m *Manager) verifyRFC(ctx context.Context, client *acme.Client, domain str
 	// it will most likely not work on another order's authorization either.
 	challengeTypes := m.supportedChallengeTypes()
 	nextTyp := 0         // challengeTypes index
+	var authErrs []error // Validation errors, possibly hinting at a solution.
 AuthorizeOrderLoop:
 	for {
 		o, err := client.AuthorizeOrder(ctx, acme.DomainIDs(domain))
@@ -765,18 +766,29 @@ AuthorizeOrderLoop:
 				nextTyp++
 			}
 			if chal == nil {
-				return nil, fmt.Errorf("acme/autocert: unable to satisfy %q for domain %q: no viable challenge type found", z.URI, domain)
+				details := ""
+				if len(authErrs) > 0 {
+					details = " (failures: " + authErrs[0].Error()
+					for _, err := range authErrs[1:] {
+						details += "; " + err.Error()
+					}
+					details += ")"
+				}
+				return nil, fmt.Errorf("acme/autocert: unable to satisfy %q for domain %q: no viable challenge type found%s", z.URI, domain, details)
 			}
 			// Respond to the challenge and wait for validation result.
 			cleanup, err := m.fulfill(ctx, client, chal, domain)
 			if err != nil {
+				authErrs = append(authErrs, fmt.Errorf("challenge %s: preparing response for validation: %v", chal.Type, err))
 				continue AuthorizeOrderLoop
 			}
 			defer cleanup()
 			if _, err := client.Accept(ctx, chal); err != nil {
+				authErrs = append(authErrs, fmt.Errorf("challenge %s: requesting validation: %v", chal.Type, err))
 				continue AuthorizeOrderLoop
 			}
 			if _, err := client.WaitAuthorization(ctx, z.URI); err != nil {
+				authErrs = append(authErrs, fmt.Errorf("challenge %s: %v", chal.Type, err))
 				continue AuthorizeOrderLoop
 			}
 		}
@@ -785,6 +797,7 @@ AuthorizeOrderLoop:
 		// Wait for the CA to update the order status.
 		o, err = client.WaitOrder(ctx, o.URI)
 		if err != nil {
+			authErrs = append(authErrs, fmt.Errorf("waiting for order: %v", err))
 			continue AuthorizeOrderLoop
 		}
 		return o, nil

vendor/modules.txt

@@ -17,7 +17,7 @@ github.com/mjl-/adns
 github.com/mjl-/adns/internal/bytealg
 github.com/mjl-/adns/internal/itoa
 github.com/mjl-/adns/internal/singleflight
-# github.com/mjl-/autocert v0.0.0-20231009155929-d0d48f2f0290
+# github.com/mjl-/autocert v0.0.0-20231013072455-c361ae2e20a6
 ## explicit; go 1.20
 github.com/mjl-/autocert
 # github.com/mjl-/bstore v0.0.2