1 files changed, 102 insertions, 0 deletions
diff --git a/internal/message/fediprocess.go b/internal/message/fediprocess.go
new file mode 100644
index 000000000..6dc6330cf
--- /dev/null
+++ b/internal/message/fediprocess.go
@@ -0,0 +1,102 @@
+package message
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/go-fed/activity/streams"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+// authenticateAndDereferenceFediRequest authenticates the HTTP signature of an incoming federation request, using the given
+// username to perform the validation. It will *also* dereference the originator of the request and return it as a gtsmodel account
+// for further processing. NOTE that this function will have the side effect of putting the dereferenced account into the database,
+// and passing it into the processor through a channel for further asynchronous processing.
+func (p *processor) authenticateAndDereferenceFediRequest(username string, r *http.Request) (*gtsmodel.Account, error) {
+
+	// first authenticate
+	requestingAccountURI, err := p.federator.AuthenticateFederatedRequest(username, r)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't authenticate request for username %s: %s", username, err)
+	}
+
+	// OK now we can do the dereferencing part
+	// we might already have an entry for this account so check that first
+	requestingAccount := &gtsmodel.Account{}
+
+	err = p.db.GetWhere("uri", requestingAccountURI.String(), requestingAccount)
+	if err == nil {
+		// we do have it yay, return it
+		return requestingAccount, nil
+	}
+
+	if _, ok := err.(db.ErrNoEntries); !ok {
+		// something has actually gone wrong so bail
+		return nil, fmt.Errorf("database error getting account with uri %s: %s", requestingAccountURI.String(), err)
+	}
+
+	// we just don't have an entry for this account yet
+	// what we do now should depend on our chosen federation method
+	// for now though, we'll just dereference it
+	// TODO: slow-fed
+	requestingPerson, err := p.federator.DereferenceRemoteAccount(username, requestingAccountURI)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't dereference %s: %s", requestingAccountURI.String(), err)
+	}
+
+	// convert it to our internal account representation
+	requestingAccount, err = p.tc.ASRepresentationToAccount(requestingPerson)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't convert dereferenced uri %s to gtsmodel account: %s", requestingAccountURI.String(), err)
+	}
+
+	// shove it in the database for later
+	if err := p.db.Put(requestingAccount); err != nil {
+		return nil, fmt.Errorf("database error inserting account with uri %s: %s", requestingAccountURI.String(), err)
+	}
+
+	// put it in our channel to queue it for async processing
+	p.FromFederator() <- FromFederator{
+		APObjectType:   gtsmodel.ActivityStreamsProfile,
+		APActivityType: gtsmodel.ActivityStreamsCreate,
+		Activity:       requestingAccount,
+	}
+
+	return requestingAccount, nil
+}
+
+func (p *processor) GetFediUser(requestedUsername string, request *http.Request) (interface{}, ErrorWithCode) {
+	// get the account the request is referring to
+	requestedAccount := &gtsmodel.Account{}
+	if err := p.db.GetLocalAccountByUsername(requestedUsername, requestedAccount); err != nil {
+		return nil, NewErrorNotFound(fmt.Errorf("database error getting account with username %s: %s", requestedUsername, err))
+	}
+
+	// authenticate the request
+	requestingAccount, err := p.authenticateAndDereferenceFediRequest(requestedUsername, request)
+	if err != nil {
+		return nil, NewErrorNotAuthorized(err)
+	}
+
+	blocked, err := p.db.Blocked(requestedAccount.ID, requestingAccount.ID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	if blocked {
+		return nil, NewErrorNotAuthorized(fmt.Errorf("block exists between accounts %s and %s", requestedAccount.ID, requestingAccount.ID))
+	}
+
+	requestedPerson, err := p.tc.AccountToAS(requestedAccount)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	data, err := streams.Serialize(requestedPerson)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	return data, nil
+}