Migrate to profile ids

client/internal/profilemanager/id.go

@@ -0,0 +1,110 @@
+package profilemanager
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"path/filepath"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+const (
+	// profileIDByteLen is the number of random bytes generated for a new
+	// profile ID. The resulting hex string is twice this length.
+	profileIDByteLen = 16
+
+	// shortIDLen is the number of leading characters of an ID we render in
+	// list output. Profiles per device are few, so 8 chars is collision-safe
+	// in practice and easy to type as a prefix.
+	shortIDLen = 8
+
+	// maxProfileNameLen caps the human-readable profile name to keep table
+	// output legible and prevent denial-of-service via huge JSON fields.
+	maxProfileNameLen = 128
+
+	// maxProfileIDLen bounds the on-disk filename we'll accept. New
+	// IDs are 32 hex chars, legacy stems are sanitized profile names. The
+	// cap is generous enough to cover both without permitting absurdly
+	// long filenames.
+	maxProfileIDLen = 64
+)
+
+// generateProfileID returns a new random hex ID for a profile file.
+func generateProfileID() (string, error) {
+	buf := make([]byte, profileIDByteLen)
+	if _, err := rand.Read(buf); err != nil {
+		return "", fmt.Errorf("read random bytes: %w", err)
+	}
+	return hex.EncodeToString(buf), nil
+}
+
+// isValidProfileFilenameStem reports whether s is safe to use as the stem
+// of a profile JSON filename.
+func isValidProfileFilenameStem(s string) bool {
+	if s == "" || len(s) > maxProfileIDLen {
+		return false
+	}
+	if s == defaultProfileName {
+		return true
+	}
+	if strings.ContainsAny(s, `/\`) || strings.Contains(s, "..") {
+		return false
+	}
+	// filepath.Base catches any leftover separators on platforms with
+	// exotic path conventions.
+	if filepath.Base(s) != s {
+		return false
+	}
+	for _, r := range s {
+		if !(unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' || r == '-') {
+			return false
+		}
+	}
+	return true
+}
+
+// sanitizeDisplayName normalizes a user-supplied profile display name for
+// storage. It strips ASCII control characters, rejects invalid UTF-8, and
+// caps the length. Emojis, spaces, punctuation, and non-ASCII letters are
+// preserved. Returns an error if nothing usable remains.
+func sanitizeDisplayName(name string) (string, error) {
+	if !utf8.ValidString(name) {
+		return "", fmt.Errorf("name is not valid UTF-8")
+	}
+	name = StripCtrlChars(name)
+	name = strings.TrimSpace(name)
+	if name == "" {
+		return "", fmt.Errorf("name is empty after sanitization")
+	}
+	if utf8.RuneCountInString(name) > maxProfileNameLen {
+		return "", fmt.Errorf("name exceeds %d characters", maxProfileNameLen)
+	}
+	return name, nil
+}
+
+// StripCtrlChars control characters from a name before printing it.
+func StripCtrlChars(name string) string {
+	var b strings.Builder
+	b.Grow(len(name))
+	for _, r := range name {
+		// Skip C0 controls and DEL, plus C1 controls (0x80–0x9F).
+		if r < 0x20 || r == 0x7F || (r >= 0x80 && r <= 0x9F) {
+			continue
+		}
+		b.WriteRune(r)
+	}
+	return b.String()
+}
+
+// ShortID truncates an ID for display.
+func ShortID(id string) string {
+	if id == DefaultProfileName {
+		return id
+	}
+	if len(id) <= shortIDLen {
+		return id
+	}
+	return id[:shortIDLen]
+}