server/internal/internal/names: validate names

This commit is a step towards a goal to make names less ceremonial
outside of the registry client. Clients of the registry package can
treat names as opaque strings, and the registry package will handle
parsing, validating, and normalizing names.

Ideally we end up with the names package tucked away in an internal
package for good. We'll see how things go.

Also, this package name is not permanent. This another step in the
on-going process of refactoring the server code, and at some point it
will most likely be renamed/moved.

server/internal/client/ollama/registry.go

@@ -24,6 +24,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"strconv"
 	"strings"
 	"sync/atomic"
@@ -53,7 +54,7 @@ var (
 
 	// ErrMissingModel is returned when the model part of a name is missing
 	// or invalid.
-	ErrNameInvalid = errors.New("invalid name; must be in the form {scheme://}{host/}{namespace/}[model]{:tag}{@digest}")
+	ErrNameInvalid = errors.New("invalid or missing name")
 
 	// ErrCached is passed to [Trace.PushUpdate] when a layer already
 	// exists. It is a non-fatal error and is never returned by [Registry.Push].
@@ -205,10 +206,18 @@ type Registry struct {
 	// It is only used when a layer is larger than [MaxChunkingThreshold].
 	MaxChunkSize int64
 
-	// NameMask, if set, is the name used to convert non-fully qualified
+	// Mask, if set, is the name used to convert non-fully qualified
 	// names to fully qualified names. If empty, the default mask
 	// ("registry.ollama.ai/library/_:latest") is used.
-	NameMask string
+	Mask string
+}
+
+func (r *Registry) completeName(name string) names.Name {
+	mask := defaultMask
+	if r.Mask != "" {
+		mask = names.Parse(r.Mask)
+	}
+	return names.Merge(names.Parse(name), mask)
 }
 
 // DefaultRegistry returns a new Registry configured from the environment. The
@@ -243,52 +252,6 @@ func DefaultRegistry() (*Registry, error) {
 	return &rc, nil
 }
 
-type PushParams struct {
-	// From is an optional destination name for the model. If empty, the
-	// destination name is the same as the source name.
-	From string
-}
-
-// parseName parses name using [names.ParseExtended] and then merges the name with the
-// default name, and checks that the name is fully qualified. If a digest is
-// present, it parse and returns it with the other fields as their zero values.
-//
-// It returns an error if the name is not fully qualified, or if the digest, if
-// any, is invalid.
-//
-// The scheme is returned as provided by [names.ParseExtended].
-func parseName(s, mask string) (scheme string, n names.Name, d blob.Digest, err error) {
-	maskName := defaultMask
-	if mask != "" {
-		maskName = names.Parse(mask)
-		if !maskName.IsFullyQualified() {
-			return "", names.Name{}, blob.Digest{}, fmt.Errorf("invalid name mask: %s", mask)
-		}
-	}
-	scheme, n, ds := names.ParseExtended(s)
-	if !n.IsValid() {
-		return "", names.Name{}, blob.Digest{}, fmt.Errorf("%w: %q", ErrNameInvalid, s)
-	}
-	n = names.Merge(n, maskName)
-	if ds != "" {
-		// Digest is present. Validate it.
-		d, err = blob.ParseDigest(ds)
-		if err != nil {
-			return "", names.Name{}, blob.Digest{}, err
-		}
-	}
-
-	// The name check is deferred until after the digest check because we
-	// say that digests take precedence over names, and so should there
-	// errors when being parsed.
-	if !n.IsFullyQualified() {
-		return "", names.Name{}, blob.Digest{}, fmt.Errorf("%w: %q", ErrNameInvalid, s)
-	}
-
-	scheme = cmp.Or(scheme, "https")
-	return scheme, n, d, nil
-}
-
 func (r *Registry) maxStreams() int {
 	n := cmp.Or(r.MaxStreams, runtime.GOMAXPROCS(0))
 
@@ -308,6 +271,12 @@ func (r *Registry) maxChunkSize() int64 {
 	return cmp.Or(r.MaxChunkSize, DefaultMaxChunkSize)
 }
 
+type PushParams struct {
+	// From is an optional destination name for the model. If empty, the
+	// destination name is the same as the source name.
+	From string
+}
+
 // Push pushes the model with the name in the cache to the remote registry.
 func (r *Registry) Push(ctx context.Context, c *blob.DiskCache, name string, p *PushParams) error {
 	if p == nil {
@@ -337,7 +306,7 @@ func (r *Registry) Push(ctx context.Context, c *blob.DiskCache, name string, p *
 
 	t := traceFromContext(ctx)
 
-	scheme, n, _, err := parseName(name, r.NameMask)
+	scheme, n, _, err := parseName(name, r.Mask)
 	if err != nil {
 		// This should never happen since ResolveLocal should have
 		// already validated the name.
@@ -431,7 +400,7 @@ func canRetry(err error) bool {
 // typically slower than splitting the model up across layers, and is mostly
 // utilized for layers of type equal to "application/vnd.ollama.image".
 func (r *Registry) Pull(ctx context.Context, c *blob.DiskCache, name string) error {
-	scheme, n, _, err := parseName(name, r.NameMask)
+	scheme, n, _, err := parseName(name, r.Mask)
 	if err != nil {
 		return err
 	}
@@ -582,9 +551,9 @@ func (r *Registry) Pull(ctx context.Context, c *blob.DiskCache, name string) err
 // Unlink is like [blob.DiskCache.Unlink], but makes name fully qualified
 // before attempting to unlink the model.
 func (r *Registry) Unlink(c *blob.DiskCache, name string) (ok bool, _ error) {
-	_, n, _, err := parseName(name, r.NameMask)
-	if err != nil {
-		return false, err
+	n := r.completeName(name)
+	if !n.IsFullyQualified() {
+		return false, fmt.Errorf("%w: %q", ErrNameInvalid, name)
 	}
 	return c.Unlink(n.String())
 }
@@ -658,9 +627,9 @@ type Layer struct {
 }
 
 // ResolveLocal resolves a name to a Manifest in the local cache. The name is
-// parsed using [names.ParseExtended] but the scheme is ignored.
+// parsed using [names.Split] but the scheme is ignored.
 func (r *Registry) ResolveLocal(c *blob.DiskCache, name string) (*Manifest, error) {
-	_, n, d, err := parseName(name, r.NameMask)
+	_, n, d, err := parseName(name, r.Mask)
 	if err != nil {
 		return nil, err
 	}
@@ -686,7 +655,7 @@ func (r *Registry) ResolveLocal(c *blob.DiskCache, name string) (*Manifest, erro
 
 // Resolve resolves a name to a Manifest in the remote registry.
 func (r *Registry) Resolve(ctx context.Context, name string) (*Manifest, error) {
-	scheme, n, d, err := parseName(name, r.NameMask)
+	scheme, n, d, err := parseName(name, r.Mask)
 	if err != nil {
 		return nil, err
 	}
@@ -869,3 +838,69 @@ func maybeUnexpectedEOF(err error) error {
 	}
 	return err
 }
+
+type publicError struct {
+	wrapped error
+	message string
+}
+
+func withPublicMessagef(err error, message string, args ...any) error {
+	return publicError{wrapped: err, message: fmt.Sprintf(message, args...)}
+}
+
+func (e publicError) Error() string { return e.message }
+func (e publicError) Unwrap() error { return e.wrapped }
+
+var supportedSchemes = []string{
+	"http",
+	"https",
+	"https+insecure",
+}
+
+var supportedSchemesMessage = fmt.Sprintf("supported schemes are %v", strings.Join(supportedSchemes, ", "))
+
+// parseName parses and validates an extended name, returning the scheme, name,
+// and digest.
+//
+// If the scheme is empty, scheme will be "https". If an unsupported scheme is
+// given, [ErrNameInvalid] wrapped with a display friendly message is returned.
+//
+// If the digest is invalid, [ErrNameInvalid] wrapped with a display friendly
+// message is returned.
+//
+// If the name is not, once merged with the mask, fully qualified,
+// [ErrNameInvalid] wrapped with a display friendly message is returned.
+func parseName(s string, mask string) (scheme string, _ names.Name, _ blob.Digest, _ error) {
+	scheme, name, digest := names.Split(s)
+	scheme = cmp.Or(scheme, "https")
+	if !slices.Contains(supportedSchemes, scheme) {
+		err := withPublicMessagef(ErrNameInvalid, "unsupported scheme: %q: %s", scheme, supportedSchemesMessage)
+		return "", names.Name{}, blob.Digest{}, err
+	}
+
+	var d blob.Digest
+	if digest != "" {
+		var err error
+		d, err = blob.ParseDigest(digest)
+		if err != nil {
+			err = withPublicMessagef(ErrNameInvalid, "invalid digest: %q", digest)
+			return "", names.Name{}, blob.Digest{}, err
+		}
+		if name == "" {
+			// We have can resolve a manifest from a digest only,
+			// so skip name validation and return the scheme and
+			// digest.
+			return scheme, names.Name{}, d, nil
+		}
+	}
+
+	maskName := defaultMask
+	if mask != "" {
+		maskName = names.Parse(mask)
+	}
+	n := names.Merge(names.Parse(name), maskName)
+	if !n.IsFullyQualified() {
+		return "", names.Name{}, blob.Digest{}, fmt.Errorf("%w: %q", ErrNameInvalid, s)
+	}
+	return scheme, n, d, nil
+}

server/internal/client/ollama/registry_test.go

@@ -84,14 +84,14 @@ func newClient(t *testing.T, h http.HandlerFunc) (*Registry, *blob.DiskCache) {
 		}
 	}
 
-	rc := &Registry{
+	r := &Registry{
 		HTTPClient: &http.Client{
 			Transport: recordRoundTripper(h),
 		},
 	}
 
 	link := func(name string, manifest string) {
-		_, n, _, err := parseName(name, rc.NameMask)
+		_, n, _, err := parseName(name, r.Mask)
 		if err != nil {
 			panic(err)
 		}
@@ -122,7 +122,7 @@ func newClient(t *testing.T, h http.HandlerFunc) (*Registry, *blob.DiskCache) {
 	commit("sizemismatch", mklayer("exists"), &Layer{Digest: blob.DigestFromBytes("present"), Size: 499})
 	link("invalid", "!!!!!")
 
-	return rc, c
+	return r, c
 }
 
 func okHandler(w http.ResponseWriter, r *http.Request) {
@@ -145,29 +145,6 @@ func importBytes(t *testing.T, c *blob.DiskCache, data string) blob.Digest {
 	return d
 }
 
-func TestRegistryPushInvalidNames(t *testing.T) {
-	rc, c := newClient(t, nil)
-
-	cases := []struct {
-		name string
-		err  error
-	}{
-		{"", ErrNameInvalid},
-		{"@", ErrNameInvalid},
-		{"@x", blob.ErrInvalidDigest},
-	}
-
-	for _, tt := range cases {
-		t.Run(tt.name, func(t *testing.T) {
-			// Create a new registry and push a new image.
-			err := rc.Push(t.Context(), c, tt.name, nil)
-			if !errors.Is(err, tt.err) {
-				t.Errorf("err = %v; want %v", err, tt.err)
-			}
-		})
-	}
-}
-
 func withTraceUnexpected(ctx context.Context) (context.Context, *Trace) {
 	t := &Trace{Update: func(*Layer, int64, error) { panic("unexpected") }}
 	return WithTrace(ctx, t), t
@@ -622,7 +599,7 @@ func TestInsecureSkipVerify(t *testing.T) {
 	}))
 	defer s.Close()
 
-	const name = "ollama.com/library/insecure"
+	const name = "library/insecure"
 
 	var rc Registry
 	url := fmt.Sprintf("https://%s/%s", s.Listener.Addr(), name)
@@ -724,3 +701,38 @@ func TestErrorUnmarshal(t *testing.T) {
 		})
 	}
 }
+
+// TestParseNameErrors tests that parseName returns errors messages with enough
+// detail for users to debug naming issues they may encounter. Previous to this
+// test, the error messages were not very helpful and each problem was reported
+// as the same message.
+//
+// It is only for testing error messages, not that all invalids and valids are
+// covered. Those are in other tests for names.Name and blob.Digest.
+func TestParseNameErrors(t *testing.T) {
+	cases := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{"x", nil, ""},
+		{"x@", nil, ""},
+
+		{"", ErrNameInvalid, `invalid or missing name: ""`},
+		{"://", ErrNameInvalid, `invalid or missing name: "://"`},
+		{"x://", ErrNameInvalid, `unsupported scheme: "x": supported schemes are http, https, https+insecure`},
+
+		{"@sha123-1234", ErrNameInvalid, `invalid digest: "sha123-1234"`},
+		{"x@sha123-1234", ErrNameInvalid, `invalid digest: "sha123-1234"`},
+	}
+
+	for _, tt := range cases {
+		_, _, _, err := parseName(tt.name, DefaultMask)
+		if !errors.Is(err, tt.err) {
+			t.Errorf("[%s]: err = %v; want %v", tt.name, err, tt.err)
+		}
+		if err != nil && !strings.Contains(err.Error(), tt.want) {
+			t.Errorf("[%s]: err =\n\t%v\nwant\n\t%v", tt.name, err, tt.want)
+		}
+	}
+}

server/internal/internal/names/name.go

@@ -8,7 +8,7 @@ import (
 	"github.com/ollama/ollama/server/internal/internal/stringsx"
 )
 
-const MaxNameLength = 50 + 1 + 50 + 1 + 50 // <namespace>/<model>:<tag>
+const MaxNameLength = 350 + 1 + 80 + 1 + 80 + 1 + 80 // <host>/<namespace>/<model>:<tag>
 
 type Name struct {
 	// Make incomparable to enfoce use of Compare / Equal for
@@ -25,19 +25,12 @@ type Name struct {
 // format of a valid name string is:
 //
 //	  s:
-//		  { host } "/" { namespace } "/" { model } ":" { tag } "@" { digest }
 //		  { host } "/" { namespace } "/" { model } ":" { tag }
-//		  { host } "/" { namespace } "/" { model } "@" { digest }
 //		  { host } "/" { namespace } "/" { model }
-//		  { namespace } "/" { model } ":" { tag } "@" { digest }
 //		  { namespace } "/" { model } ":" { tag }
-//		  { namespace } "/" { model } "@" { digest }
 //		  { namespace } "/" { model }
-//		  { model } ":" { tag } "@" { digest }
 //		  { model } ":" { tag }
-//		  { model } "@" { digest }
 //		  { model }
-//		  "@" { digest }
 //	  host:
 //	      pattern: { alphanum | "_" } { alphanum | "_" | "-" | "." | ":" }*
 //	      length:  [1, 350]
@@ -50,9 +43,6 @@ type Name struct {
 //	  tag:
 //	      pattern: { alphanum | "_" } { alphanum | "-" | "_" | "." }*
 //	      length:  [1, 80]
-//	  digest:
-//	      pattern: { alphanum | "_" } { alphanum | "-" | ":" }*
-//	      length:  [1, 80]
 //
 // The name returned is not guaranteed to be valid. If it is not valid, the
 // field values are left in an undefined state. Use [Name.IsValid] to check
@@ -82,23 +72,17 @@ func Parse(s string) Name {
 	}
 }
 
-// ParseExtended parses and returns any scheme, Name, and digest from from s in
-// the the form [scheme://][name][@digest]. All parts are optional.
-//
-// If the scheme is present, it must be followed by "://". The digest is
-// prefixed by "@" and comes after the name. The name is parsed using [Parse].
-//
-// The scheme and digest are stripped before the name is parsed by [Parse].
-//
-// For convience, the scheme is never empty. If the scheme is not present, the
-// returned scheme is "https".
+// Split splits an extended name string into its scheme, name, and digest
+// parts.
 //
 // Examples:
 //
 //	http://ollama.com/bmizerany/smol:latest@digest
 //	https://ollama.com/bmizerany/smol:latest
 //	ollama.com/bmizerany/smol:latest@digest // returns "https" scheme.
-func ParseExtended(s string) (scheme string, _ Name, digest string) {
+//	model@digest
+//	@digest
+func Split(s string) (scheme, name, digest string) {
 	i := strings.Index(s, "://")
 	if i >= 0 {
 		scheme = s[:i]
@@ -109,21 +93,7 @@ func ParseExtended(s string) (scheme string, _ Name, digest string) {
 		digest = s[i+1:]
 		s = s[:i]
 	}
-	return scheme, Parse(s), digest
-}
-
-func FormatExtended(scheme string, n Name, digest string) string {
-	var b strings.Builder
-	if scheme != "" {
-		b.WriteString(scheme)
-		b.WriteString("://")
-	}
-	b.WriteString(n.String())
-	if digest != "" {
-		b.WriteByte('@')
-		b.WriteString(digest)
-	}
-	return b.String()
+	return scheme, s, digest
 }
 
 // Merge merges two names into a single name. Non-empty host, namespace, and
@@ -141,39 +111,68 @@ func Merge(a, b Name) Name {
 
 // IsValid returns true if the name is valid.
 func (n Name) IsValid() bool {
-	if n.h != "" && !isValidHost(n.h) {
+	if n.h != "" && !isValidPart(partHost, n.h) {
 		return false
 	}
-	if n.n != "" && !isValidNamespace(n.n) {
+	if n.n != "" && !isValidPart(partNamespace, n.n) {
 		return false
 	}
-	if n.m != "" && !isValidModel(n.m) {
+	if n.t != "" && !isValidPart(partTag, n.t) {
 		return false
 	}
-	if n.t != "" && !isValidTag(n.t) {
-		return false
-	}
-	return true
+
+	// at bare minimum, model must be present and valid
+	return n.m != "" && isValidPart(partModel, n.m)
 }
 
 func (n Name) IsFullyQualified() bool {
 	return n.IsValid() && n.h != "" && n.n != "" && n.m != "" && n.t != ""
 }
 
-func isValidHost(_ string) bool {
-	return true // TODO: implement
+const (
+	partHost = iota
+	partNamespace
+	partModel
+	partTag
+)
+
+func isValidPart(kind int, s string) bool {
+	maxlen := 80
+	if kind == partHost {
+		maxlen = 350
+	}
+	if len(s) > maxlen {
+		return false
+	}
+
+	for i := range s {
+		if i == 0 {
+			if !isAlphanumericOrUnderscore(s[i]) {
+				return false
+			}
+			continue
+		}
+		switch s[i] {
+		case '_', '-':
+		case '.':
+			if kind == partNamespace {
+				return false
+			}
+		case ':':
+			if kind != partHost {
+				return false
+			}
+		default:
+			if !isAlphanumericOrUnderscore(s[i]) {
+				return false
+			}
+		}
+	}
+	return true
 }
 
-func isValidNamespace(_ string) bool {
-	return true // TODO: implement
-}
-
-func isValidModel(_ string) bool {
-	return true // TODO: implement
-}
-
-func isValidTag(_ string) bool {
-	return true // TODO: implement
+func isAlphanumericOrUnderscore(c byte) bool {
+	return c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z' || c >= '0' && c <= '9' || c == '_'
 }
 
 func (n Name) Host() string      { return n.h }

server/internal/internal/names/name_test.go

@@ -81,15 +81,11 @@ func TestParseExtended(t *testing.T) {
 	}
 	for _, tt := range cases {
 		t.Run(tt.in, func(t *testing.T) {
-			scheme, name, digest := ParseExtended(tt.in)
-			if scheme != tt.wantScheme || name.Compare(tt.wantName) != 0 || digest != tt.wantDigest {
+			scheme, name, digest := Split(tt.in)
+			n := Parse(name)
+			if scheme != tt.wantScheme || n.Compare(tt.wantName) != 0 || digest != tt.wantDigest {
 				t.Errorf("ParseExtended(%q) = %q, %#v, %q, want %q, %#v, %q", tt.in, scheme, name, digest, tt.wantScheme, tt.wantName, tt.wantDigest)
 			}
-
-			// Round trip
-			if got := FormatExtended(scheme, name, digest); got != tt.in {
-				t.Errorf("FormatExtended(%q, %q, %q) = %q", scheme, name, digest, got)
-			}
 		})
 	}
 }
@@ -150,3 +146,75 @@ func BenchmarkParseName(b *testing.B) {
 		junkName = Parse("h/n/m:t")
 	}
 }
+
+const (
+	part80  = "88888888888888888888888888888888888888888888888888888888888888888888888888888888"
+	part350 = "33333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333333"
+)
+
+var testCases = map[string]bool{ // name -> valid
+	"": false,
+
+	"_why/_the/_lucky:_stiff": true,
+
+	// minimal
+	"h/n/m:t": true,
+
+	"host/namespace/model:tag": true,
+	"host/namespace/model":     true,
+	"namespace/model":          true,
+	"model":                    true,
+
+	// long (but valid)
+	part80 + "/" + part80 + "/" + part80 + ":" + part80:  true,
+	part350 + "/" + part80 + "/" + part80 + ":" + part80: true,
+
+	// too long
+	part80 + "/" + part80 + "/" + part80 + ":" + part350:       false,
+	"x" + part350 + "/" + part80 + "/" + part80 + ":" + part80: false,
+
+	"h/nn/mm:t": true, // bare minimum part sizes
+
+	// unqualified
+	"m":     true,
+	"n/m:":  true,
+	"h/n/m": true,
+	"@t":    false,
+	"m@d":   false,
+
+	// invalids
+	"^":      false,
+	"mm:":    true,
+	"/nn/mm": true,
+	"//":     false, // empty model
+	"//mm":   true,
+	"hh//":   false, // empty model
+	"//mm:@": false,
+	"00@":    false,
+	"@":      false,
+
+	// not starting with alphanum
+	"-hh/nn/mm:tt": false,
+	"hh/-nn/mm:tt": false,
+	"hh/nn/-mm:tt": false,
+	"hh/nn/mm:-tt": false,
+
+	// smells like a flag
+	"-h": false,
+
+	// hosts
+	"host:https/namespace/model:tag": true,
+
+	// colon in non-host part before tag
+	"host/name:space/model:tag": false,
+}
+
+func TestParseNameValidation(t *testing.T) {
+	for s, valid := range testCases {
+		got := Parse(s)
+		if got.IsValid() != valid {
+			t.Logf("got: %v", got)
+			t.Errorf("Parse(%q).IsValid() = %v; want !%[2]v", s, got.IsValid())
+		}
+	}
+}

server/internal/registry/server.go

@@ -204,7 +204,7 @@ func (s *Local) handleDelete(_ http.ResponseWriter, r *http.Request) error {
 		return err
 	}
 	if !ok {
-		return &serverError{404, "manifest_not_found", "manifest not found"}
+		return &serverError{404, "not_found", "model not found"}
 	}
 	return nil
 }

server/internal/registry/server_test.go

@@ -109,11 +109,8 @@ func TestServerDelete(t *testing.T) {
 	got = s.send(t, "DELETE", "/api/delete", ``)
 	checkErrorResponse(t, got, 400, "bad_request", "empty request body")
 
-	got = s.send(t, "DELETE", "/api/delete", `{"model": "!"}`)
-	checkErrorResponse(t, got, 404, "manifest_not_found", "not found")
-
 	got = s.send(t, "DELETE", "/api/delete", `{"model": "://"}`)
-	checkErrorResponse(t, got, 400, "bad_request", "invalid name")
+	checkErrorResponse(t, got, 400, "bad_request", "invalid or missing name")
 
 	got = s.send(t, "DELETE", "/unknown_path", `{}`) // valid body
 	checkErrorResponse(t, got, 404, "not_found", "not found")