OpenSSL: Add support for Chacha20-Poly1305 to kernel TLS on FreeBSD.

FreeBSD's kernel TLS supports Chacha20 for both TLS 1.2 and TLS 1.3.

NB: This commit has not yet been merged upstream as it is deemed a new
feature and did not make the feature freeze cutoff for OpenSSL 3.0.

Reviewed by:	jkim
MFC after:	5 days
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D31443

crypto/openssl/include/internal/ktls.h

@@ -38,6 +38,11 @@
 #   define OPENSSL_KTLS_AES_GCM_128
 #   define OPENSSL_KTLS_AES_GCM_256
 #   define OPENSSL_KTLS_TLS13
+#   ifdef TLS_CHACHA20_IV_LEN
+#    ifndef OPENSSL_NO_CHACHA
+#     define OPENSSL_KTLS_CHACHA20_POLY1305
+#    endif
+#   endif
 
 typedef struct tls_enable ktls_crypto_info_t;
 

crypto/openssl/ssl/ktls.c

@@ -37,6 +37,10 @@ int ktls_check_supported_cipher(const SSL *s, const EVP_CIPHER *c,
     case SSL_AES128GCM:
     case SSL_AES256GCM:
         return 1;
+# ifdef OPENSSL_KTLS_CHACHA20_POLY1305
+    case SSL_CHACHA20POLY1305:
+        return 1;
+# endif
     case SSL_AES128:
     case SSL_AES256:
         if (s->ext.use_etm)
@@ -71,6 +75,12 @@ int ktls_configure_crypto(const SSL *s, const EVP_CIPHER *c, EVP_CIPHER_CTX *dd,
         else
             crypto_info->iv_len = EVP_GCM_TLS_FIXED_IV_LEN;
         break;
+# ifdef OPENSSL_KTLS_CHACHA20_POLY1305
+    case SSL_CHACHA20POLY1305:
+        crypto_info->cipher_algorithm = CRYPTO_CHACHA20_POLY1305;
+        crypto_info->iv_len = EVP_CIPHER_CTX_iv_length(dd);
+        break;
+# endif
     case SSL_AES128:
     case SSL_AES256:
         switch (s->s3->tmp.new_cipher->algorithm_mac) {