diff --git a/crypto/bio/bio.c b/crypto/bio/bio.c
index 0e3a0d737d0..17f2afdea33 100644
--- a/crypto/bio/bio.c
+++ b/crypto/bio/bio.c
@@ -186,6 +186,26 @@ int BIO_read(BIO *bio, void *buf, int len) {
   return ret;
 }
 
+int BIO_read_ex(BIO *bio, void *data, size_t data_len, size_t *read_bytes) {
+  if (bio == NULL || read_bytes == NULL) {
+    OPENSSL_PUT_ERROR(BIO, BIO_R_NULL_PARAMETER);
+    return 0;
+  }
+
+  int read_len = (int)data_len;
+  if (data_len > INT_MAX) {
+    read_len = INT_MAX;
+  }
+
+  int ret = BIO_read(bio, data, read_len);
+  *read_bytes = ret;
+  if (ret > 0) {
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
 int BIO_gets(BIO *bio, char *buf, int len) {
   if (bio == NULL || bio->method == NULL || bio->method->bgets == NULL) {
     OPENSSL_PUT_ERROR(BIO, BIO_R_UNSUPPORTED_METHOD);
@@ -236,6 +256,28 @@ int BIO_write(BIO *bio, const void *in, int inl) {
   return ret;
 }
 
+int BIO_write_ex(BIO *bio, const void *data, size_t data_len, size_t *written_bytes) {
+  if (bio == NULL) {
+    OPENSSL_PUT_ERROR(BIO, BIO_R_NULL_PARAMETER);
+    return 0;
+  }
+
+  int write_len = (int)data_len;
+  if (data_len > INT_MAX) {
+    write_len = INT_MAX;
+  }
+
+  int ret = BIO_write(bio, data, write_len);
+  if (written_bytes != NULL) {
+    *written_bytes = ret;
+  }
+  if (ret > 0) {
+    return 1;
+  } else {
+    return 0;
+  }
+}
+
 int BIO_write_all(BIO *bio, const void *data, size_t len) {
   const uint8_t *data_u8 = data;
   while (len > 0) {
diff --git a/crypto/bio/bio_test.cc b/crypto/bio/bio_test.cc
index e76f3eb32fa..479d66c53e5 100644
--- a/crypto/bio/bio_test.cc
+++ b/crypto/bio/bio_test.cc
@@ -89,7 +89,7 @@ class OwnedSocket {
 };
 
 struct SockaddrStorage {
-  SockaddrStorage() : storage() , len(sizeof(storage)) {}
+  SockaddrStorage() : storage(), len(sizeof(storage)) {}
 
   int family() const { return storage.ss_family; }
 
@@ -1063,3 +1063,36 @@ TEST(BIOTest, InvokeConnectCallback) {
 }  // namespace
 
 INSTANTIATE_TEST_SUITE_P(All, BIOPairTest, testing::Values(false, true));
+
+TEST(BIOTest, ReadWriteEx) {
+  bssl::UniquePtr<BIO> bio(BIO_new(BIO_s_mem()));
+  ASSERT_TRUE(bio);
+
+  size_t written = 0;
+  ASSERT_TRUE(BIO_write_ex(bio.get(), "abcdef", 6, &written));
+  EXPECT_EQ(written, (size_t)6);
+
+  char buf[32];
+  size_t read = 0;
+  ASSERT_TRUE(BIO_read_ex(bio.get(), buf, sizeof(buf), &read));
+  EXPECT_GT(read, (size_t)0);
+  EXPECT_EQ(Bytes(buf, read), Bytes("abcdef"));
+
+  // Test NULL |written_bytes| behavior works.
+  read = 0;
+  ASSERT_TRUE(BIO_write_ex(bio.get(), "ghilmnop", 8, nullptr));
+  ASSERT_TRUE(BIO_read_ex(bio.get(), buf, sizeof(buf), &read));
+  EXPECT_GT(read, (size_t)0);
+  EXPECT_EQ(Bytes(buf, read), Bytes("ghilmnop"));
+
+  // Test NULL |read_bytes| behavior fails.
+  ASSERT_TRUE(BIO_write_ex(bio.get(), "ghilmnop", 8, nullptr));
+  ASSERT_FALSE(BIO_read_ex(bio.get(), buf, sizeof(buf), nullptr));
+
+  // Test that |BIO_write/read_ex| align with their non-ex counterparts, when
+  // encountering NULL data.
+  EXPECT_FALSE(BIO_write(bio.get(), nullptr, 0));
+  EXPECT_FALSE(BIO_write_ex(bio.get(), nullptr, 0, &written));
+  EXPECT_FALSE(BIO_read(bio.get(), nullptr, 0));
+  EXPECT_FALSE(BIO_read_ex(bio.get(), nullptr, 0, &read));
+}
diff --git a/include/openssl/bio.h b/include/openssl/bio.h
index 262707f5414..3f6a5a2a8b1 100644
--- a/include/openssl/bio.h
+++ b/include/openssl/bio.h
@@ -110,6 +110,11 @@ OPENSSL_EXPORT int BIO_up_ref(BIO *bio);
 // of bytes read, zero on EOF, or a negative number on error.
 OPENSSL_EXPORT int BIO_read(BIO *bio, void *data, int len);
 
+// |BIO_read_ex| calls |BIO_read| and stores the number of bytes read in
+// |read_bytes|. It returns one on success and zero otherwise.
+OPENSSL_EXPORT int BIO_read_ex(BIO *bio, void *data, size_t data_len,
+                               size_t *read_bytes);
+
 // BIO_gets reads a line from |bio| and writes at most |size| bytes into |buf|.
 // It returns the number of bytes read or a negative number on error. This
 // function's output always includes a trailing NUL byte, so it will read at
@@ -127,6 +132,12 @@ OPENSSL_EXPORT int BIO_gets(BIO *bio, char *buf, int size);
 // number of bytes written, or a negative number on error.
 OPENSSL_EXPORT int BIO_write(BIO *bio, const void *data, int len);
 
+// |BIO_write_ex| calls |BIO_write| and stores the number of bytes written in
+// |written_bytes|, unless |written_bytes| is NULL. It returns one on success
+// and zero otherwise.
+OPENSSL_EXPORT int BIO_write_ex(BIO *bio, const void *data, size_t data_len,
+                                size_t *written_bytes);
+
 // BIO_write_all writes |len| bytes from |data| to |bio|, looping as necessary.
 // It returns one if all bytes were successfully written and zero on error.
 OPENSSL_EXPORT int BIO_write_all(BIO *bio, const void *data, size_t len);
@@ -880,7 +891,7 @@ OPENSSL_EXPORT int (*BIO_meth_get_puts(const BIO_METHOD *method)) (BIO *, const
 // does not support secure heaps.
 OPENSSL_EXPORT OPENSSL_DEPRECATED const BIO_METHOD *BIO_s_secmem(void);
 
-  
+
 // General No-op Functions [Deprecated].
 
 // BIO_set_write_buffer_size returns zero.