diff --git a/boring/src/asn1.rs b/boring/src/asn1.rs
index e9b3d43d..6eb2199f 100644
--- a/boring/src/asn1.rs
+++ b/boring/src/asn1.rs
@@ -78,6 +78,79 @@ impl fmt::Display for Asn1GeneralizedTimeRef {
     }
 }
 
+/// The type of an ASN.1 value.
+#[derive(Debug, Copy, Clone, PartialEq, Eq)]
+pub struct Asn1Type(c_int);
+
+#[allow(missing_docs)] // no need to document the constants
+impl Asn1Type {
+    pub const EOC: Asn1Type = Asn1Type(ffi::V_ASN1_EOC);
+
+    pub const BOOLEAN: Asn1Type = Asn1Type(ffi::V_ASN1_BOOLEAN);
+
+    pub const INTEGER: Asn1Type = Asn1Type(ffi::V_ASN1_INTEGER);
+
+    pub const BIT_STRING: Asn1Type = Asn1Type(ffi::V_ASN1_BIT_STRING);
+
+    pub const OCTET_STRING: Asn1Type = Asn1Type(ffi::V_ASN1_OCTET_STRING);
+
+    pub const NULL: Asn1Type = Asn1Type(ffi::V_ASN1_NULL);
+
+    pub const OBJECT: Asn1Type = Asn1Type(ffi::V_ASN1_OBJECT);
+
+    pub const OBJECT_DESCRIPTOR: Asn1Type = Asn1Type(ffi::V_ASN1_OBJECT_DESCRIPTOR);
+
+    pub const EXTERNAL: Asn1Type = Asn1Type(ffi::V_ASN1_EXTERNAL);
+
+    pub const REAL: Asn1Type = Asn1Type(ffi::V_ASN1_REAL);
+
+    pub const ENUMERATED: Asn1Type = Asn1Type(ffi::V_ASN1_ENUMERATED);
+
+    pub const UTF8STRING: Asn1Type = Asn1Type(ffi::V_ASN1_UTF8STRING);
+
+    pub const SEQUENCE: Asn1Type = Asn1Type(ffi::V_ASN1_SEQUENCE);
+
+    pub const SET: Asn1Type = Asn1Type(ffi::V_ASN1_SET);
+
+    pub const NUMERICSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_NUMERICSTRING);
+
+    pub const PRINTABLESTRING: Asn1Type = Asn1Type(ffi::V_ASN1_PRINTABLESTRING);
+
+    pub const T61STRING: Asn1Type = Asn1Type(ffi::V_ASN1_T61STRING);
+
+    pub const TELETEXSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_TELETEXSTRING);
+
+    pub const VIDEOTEXSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_VIDEOTEXSTRING);
+
+    pub const IA5STRING: Asn1Type = Asn1Type(ffi::V_ASN1_IA5STRING);
+
+    pub const UTCTIME: Asn1Type = Asn1Type(ffi::V_ASN1_UTCTIME);
+
+    pub const GENERALIZEDTIME: Asn1Type = Asn1Type(ffi::V_ASN1_GENERALIZEDTIME);
+
+    pub const GRAPHICSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_GRAPHICSTRING);
+
+    pub const ISO64STRING: Asn1Type = Asn1Type(ffi::V_ASN1_ISO64STRING);
+
+    pub const VISIBLESTRING: Asn1Type = Asn1Type(ffi::V_ASN1_VISIBLESTRING);
+
+    pub const GENERALSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_GENERALSTRING);
+
+    pub const UNIVERSALSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_UNIVERSALSTRING);
+
+    pub const BMPSTRING: Asn1Type = Asn1Type(ffi::V_ASN1_BMPSTRING);
+
+    /// Constructs an `Asn1Type` from a raw OpenSSL value.
+    pub fn from_raw(value: c_int) -> Self {
+        Asn1Type(value)
+    }
+
+    /// Returns the raw OpenSSL value represented by this type.
+    pub fn as_raw(&self) -> c_int {
+        self.0
+    }
+}
+
 /// Difference between two ASN1 times.
 ///
 /// This `struct` is created by the [`diff`] method on [`Asn1TimeRef`]. See its
diff --git a/boring/src/x509/mod.rs b/boring/src/x509/mod.rs
index 08f10208..8b4a97bf 100644
--- a/boring/src/x509/mod.rs
+++ b/boring/src/x509/mod.rs
@@ -21,7 +21,9 @@ use std::ptr;
 use std::slice;
 use std::str;
 
-use crate::asn1::{Asn1BitStringRef, Asn1IntegerRef, Asn1ObjectRef, Asn1StringRef, Asn1TimeRef};
+use crate::asn1::{
+    Asn1BitStringRef, Asn1IntegerRef, Asn1ObjectRef, Asn1StringRef, Asn1TimeRef, Asn1Type,
+};
 use crate::bio::MemBioSlice;
 use crate::conf::ConfRef;
 use crate::error::ErrorStack;
@@ -826,6 +828,33 @@ impl X509NameBuilder {
         }
     }
 
+    /// Add a field entry by str with a specific type.
+    ///
+    /// This corresponds to [`X509_NAME_add_entry_by_txt`].
+    ///
+    /// [`X509_NAME_add_entry_by_txt`]: https://www.openssl.org/docs/man1.1.0/crypto/X509_NAME_add_entry_by_txt.html
+    pub fn append_entry_by_text_with_type(
+        &mut self,
+        field: &str,
+        value: &str,
+        ty: Asn1Type,
+    ) -> Result<(), ErrorStack> {
+        unsafe {
+            let field = CString::new(field).unwrap();
+            assert!(value.len() <= c_int::max_value() as usize);
+            cvt(ffi::X509_NAME_add_entry_by_txt(
+                self.0.as_ptr(),
+                field.as_ptr() as *mut _,
+                ty.as_raw(),
+                value.as_ptr(),
+                value.len() as c_int,
+                -1,
+                0,
+            ))
+            .map(|_| ())
+        }
+    }
+
     /// Add a field entry by NID.
     ///
     /// This corresponds to [`X509_NAME_add_entry_by_NID`].
@@ -847,6 +876,32 @@ impl X509NameBuilder {
         }
     }
 
+    /// Add a field entry by NID with a specific type.
+    ///
+    /// This corresponds to [`X509_NAME_add_entry_by_NID`].
+    ///
+    /// [`X509_NAME_add_entry_by_NID`]: https://www.openssl.org/docs/man1.1.0/crypto/X509_NAME_add_entry_by_NID.html
+    pub fn append_entry_by_nid_with_type(
+        &mut self,
+        field: Nid,
+        value: &str,
+        ty: Asn1Type,
+    ) -> Result<(), ErrorStack> {
+        unsafe {
+            assert!(value.len() <= c_int::max_value() as usize);
+            cvt(ffi::X509_NAME_add_entry_by_NID(
+                self.0.as_ptr(),
+                field.as_raw(),
+                ty.as_raw(),
+                value.as_ptr() as *mut _,
+                value.len() as c_int,
+                -1,
+                0,
+            ))
+            .map(|_| ())
+        }
+    }
+
     /// Return an `X509Name`.
     pub fn build(self) -> X509Name {
         self.0