diff --git a/ChangeLog b/ChangeLog
index 1b02751d3..a7e6288ee 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,8 +4,9 @@ mbed TLS ChangeLog (Sorted per branch, date)
 
 Features
    * Add new crypto primitives from RFC 7539: stream cipher Chacha20, one-time
-     authenticator Poly1305 and AEAD construct Chacha20-Poly1305. Contributed by
-     Daniel King (#485).
+     authenticator Poly1305 and AEAD construct Chacha20-Poly1305. Contributed
+     by Daniel King (#485).
+   * Add support for CHACHA20-POLY1305 ciphersuites from RFC 7905.
    * Add platform support for the Haiku OS. (https://www.haiku-os.org).
      Contributed by Augustin Cavalier.
    * Make the receive and transmit buffers independent sizes, for situations
diff --git a/configs/config-ccm-psk-tls1_2.h b/configs/config-ccm-psk-tls1_2.h
index a783e6b73..c9b58dd53 100644
--- a/configs/config-ccm-psk-tls1_2.h
+++ b/configs/config-ccm-psk-tls1_2.h
@@ -81,7 +81,7 @@
  * both ends of the connection!  (See comments in "mbedtls/ssl.h".)
  * The optimal size here depends on the typical size of records.
  */
-#define MBEDTLS_SSL_MAX_CONTENT_LEN             512
+#define MBEDTLS_SSL_MAX_CONTENT_LEN             1024
 
 #include "mbedtls/check_config.h"
 
diff --git a/include/mbedtls/ssl_ciphersuites.h b/include/mbedtls/ssl_ciphersuites.h
index 7d5eba091..cda8b4835 100644
--- a/include/mbedtls/ssl_ciphersuites.h
+++ b/include/mbedtls/ssl_ciphersuites.h
@@ -271,6 +271,15 @@ extern "C" {
 
 #define MBEDTLS_TLS_ECJPAKE_WITH_AES_128_CCM_8          0xC0FF  /**< experimental */
 
+/* RFC 7905 */
+#define MBEDTLS_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   0xCCA8 /**< TLS 1.2 */
+#define MBEDTLS_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 0xCCA9 /**< TLS 1.2 */
+#define MBEDTLS_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256     0xCCAA /**< TLS 1.2 */
+#define MBEDTLS_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256         0xCCAB /**< TLS 1.2 */
+#define MBEDTLS_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256   0xCCAC /**< TLS 1.2 */
+#define MBEDTLS_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256     0xCCAD /**< TLS 1.2 */
+#define MBEDTLS_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256     0xCCAE /**< TLS 1.2 */
+
 /* Reminder: update mbedtls_ssl_premaster_secret when adding a new key exchange.
  * Reminder: update MBEDTLS_KEY_EXCHANGE__xxx below
  */
diff --git a/library/ssl_ciphersuites.c b/library/ssl_ciphersuites.c
index 2e9a0fd79..59cdc7a80 100644
--- a/library/ssl_ciphersuites.c
+++ b/library/ssl_ciphersuites.c
@@ -47,7 +47,7 @@
  * 1. By key exchange:
  *    Forward-secure non-PSK > forward-secure PSK > ECJPAKE > other non-PSK > other PSK
  * 2. By key length and cipher:
- *    AES-256 > Camellia-256 > ARIA-256 > AES-128 > Camellia-128 > ARIA-128 > 3DES
+ *    ChaCha > AES-256 > Camellia-256 > ARIA-256 > AES-128 > Camellia-128 > ARIA-128 > 3DES
  * 3. By cipher mode when relevant GCM > CCM > CBC > CCM_8
  * 4. By hash function used when relevant
  * 5. By key exchange/auth again: EC > non-EC
@@ -57,6 +57,11 @@ static const int ciphersuite_preference[] =
 #if defined(MBEDTLS_SSL_CIPHERSUITES)
     MBEDTLS_SSL_CIPHERSUITES,
 #else
+    /* Chacha-Poly ephemeral suites */
+    MBEDTLS_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
+    MBEDTLS_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
+    MBEDTLS_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
+
     /* All AES-256 ephemeral suites */
     MBEDTLS_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
     MBEDTLS_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
@@ -127,6 +132,8 @@ static const int ciphersuite_preference[] =
     MBEDTLS_TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
 
     /* The PSK ephemeral suites */
+    MBEDTLS_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256,
+    MBEDTLS_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256,
     MBEDTLS_TLS_DHE_PSK_WITH_AES_256_GCM_SHA384,
     MBEDTLS_TLS_DHE_PSK_WITH_AES_256_CCM,
     MBEDTLS_TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384,
@@ -227,6 +234,7 @@ static const int ciphersuite_preference[] =
     MBEDTLS_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
 
     /* The RSA PSK suites */
+    MBEDTLS_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256,
     MBEDTLS_TLS_RSA_PSK_WITH_AES_256_GCM_SHA384,
     MBEDTLS_TLS_RSA_PSK_WITH_AES_256_CBC_SHA384,
     MBEDTLS_TLS_RSA_PSK_WITH_AES_256_CBC_SHA,
@@ -246,6 +254,7 @@ static const int ciphersuite_preference[] =
     MBEDTLS_TLS_RSA_PSK_WITH_3DES_EDE_CBC_SHA,
 
     /* The PSK suites */
+    MBEDTLS_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256,
     MBEDTLS_TLS_PSK_WITH_AES_256_GCM_SHA384,
     MBEDTLS_TLS_PSK_WITH_AES_256_CCM,
     MBEDTLS_TLS_PSK_WITH_AES_256_CBC_SHA384,
@@ -312,6 +321,75 @@ static const int ciphersuite_preference[] =
 
 static const mbedtls_ssl_ciphersuite_t ciphersuite_definitions[] =
 {
+#if defined(MBEDTLS_CHACHAPOLY_C) && \
+    defined(MBEDTLS_SHA256_C) && \
+    defined(MBEDTLS_SSL_PROTO_TLS1_2)
+#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED)
+    { MBEDTLS_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-ECDHE-RSA-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_ECDHE_RSA,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
+    { MBEDTLS_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-ECDHE-ECDSA-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
+    { MBEDTLS_TLS_DHE_RSA_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-DHE-RSA-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_DHE_RSA,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
+    { MBEDTLS_TLS_PSK_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-PSK-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_PSK,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
+    { MBEDTLS_TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-ECDHE-PSK-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_ECDHE_PSK,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
+    { MBEDTLS_TLS_DHE_PSK_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-DHE-PSK-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_DHE_PSK,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
+    { MBEDTLS_TLS_RSA_PSK_WITH_CHACHA20_POLY1305_SHA256,
+      "TLS-RSA-PSK-WITH-CHACHA20-POLY1305-SHA256",
+      MBEDTLS_CIPHER_CHACHA20_POLY1305, MBEDTLS_MD_SHA256,
+      MBEDTLS_KEY_EXCHANGE_RSA_PSK,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      MBEDTLS_SSL_MAJOR_VERSION_3, MBEDTLS_SSL_MINOR_VERSION_3,
+      0 },
+#endif
+#endif /* MBEDTLS_CHACHAPOLY_C &&
+          MBEDTLS_SHA256_C &&
+          MBEDTLS_SSL_PROTO_TLS1_2 */
 #if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
 #if defined(MBEDTLS_AES_C)
 #if defined(MBEDTLS_SHA1_C)
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 12a20180d..1c35f0dec 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -698,18 +698,32 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl )
     transform->keylen = cipher_info->key_bitlen / 8;
 
     if( cipher_info->mode == MBEDTLS_MODE_GCM ||
-        cipher_info->mode == MBEDTLS_MODE_CCM )
+        cipher_info->mode == MBEDTLS_MODE_CCM ||
+        cipher_info->mode == MBEDTLS_MODE_CHACHAPOLY )
     {
+        size_t taglen, explicit_ivlen;
+
         transform->maclen = 0;
         mac_key_len = 0;
 
+        /* All modes haves 96-bit IVs;
+         * GCM and CCM has 4 implicit and 8 explicit bytes
+         * ChachaPoly has all 12 bytes implicit
+         */
         transform->ivlen = 12;
-        transform->fixed_ivlen = 4;
+        if( cipher_info->mode == MBEDTLS_MODE_CHACHAPOLY )
+            transform->fixed_ivlen = 12;
+        else
+            transform->fixed_ivlen = 4;
 
-        /* Minimum length is expicit IV + tag */
-        transform->minlen = transform->ivlen - transform->fixed_ivlen
-                            + ( transform->ciphersuite_info->flags &
-                                MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16 );
+        /* All modes have 128-bit tags, except CCM_8 (ciphersuite flag) */
+        taglen = transform->ciphersuite_info->flags &
+                  MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
+
+
+        /* Minimum length of encrypted record */
+        explicit_ivlen = transform->ivlen - transform->fixed_ivlen;
+        transform->minlen = explicit_ivlen + taglen;
     }
     else
     {
@@ -1407,17 +1421,26 @@ static int ssl_encrypt_buf( mbedtls_ssl_context *ssl )
     }
     else
 #endif /* MBEDTLS_ARC4_C || MBEDTLS_CIPHER_NULL_CIPHER */
-#if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CCM_C)
+#if defined(MBEDTLS_GCM_C) || \
+    defined(MBEDTLS_CCM_C) || \
+    defined(MBEDTLS_CHACHAPOLY_C)
     if( mode == MBEDTLS_MODE_GCM ||
-        mode == MBEDTLS_MODE_CCM )
+        mode == MBEDTLS_MODE_CCM ||
+        mode == MBEDTLS_MODE_CHACHAPOLY )
     {
         int ret;
         size_t enc_msglen, olen;
         unsigned char *enc_msg;
         unsigned char add_data[13];
-        unsigned char taglen = ssl->transform_out->ciphersuite_info->flags &
+        unsigned char iv[12];
+        mbedtls_ssl_transform *transform = ssl->transform_out;
+        unsigned char taglen = transform->ciphersuite_info->flags &
                                MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
+        size_t explicit_ivlen = transform->ivlen - transform->fixed_ivlen;
 
+        /*
+         * Prepare additional authenticated data
+         */
         memcpy( add_data, ssl->out_ctr, 8 );
         add_data[8]  = ssl->out_msgtype;
         mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
@@ -1425,44 +1448,57 @@ static int ssl_encrypt_buf( mbedtls_ssl_context *ssl )
         add_data[11] = ( ssl->out_msglen >> 8 ) & 0xFF;
         add_data[12] = ssl->out_msglen & 0xFF;
 
-        MBEDTLS_SSL_DEBUG_BUF( 4, "additional data used for AEAD",
-                       add_data, 13 );
+        MBEDTLS_SSL_DEBUG_BUF( 4, "additional data for AEAD", add_data, 13 );
 
         /*
          * Generate IV
          */
-        if( ssl->transform_out->ivlen - ssl->transform_out->fixed_ivlen != 8 )
+        if( transform->ivlen == 12 && transform->fixed_ivlen == 4 )
+        {
+            /* GCM and CCM: fixed || explicit (=seqnum) */
+            memcpy( iv, transform->iv_enc, transform->fixed_ivlen );
+            memcpy( iv + transform->fixed_ivlen, ssl->out_ctr, 8 );
+            memcpy( ssl->out_iv, ssl->out_ctr, 8 );
+
+        }
+        else if( transform->ivlen == 12 && transform->fixed_ivlen == 12 )
+        {
+            /* ChachaPoly: fixed XOR sequence number */
+            unsigned char i;
+
+            memcpy( iv, transform->iv_enc, transform->fixed_ivlen );
+
+            for( i = 0; i < 8; i++ )
+                iv[i+4] ^= ssl->out_ctr[i];
+        }
+        else
         {
             /* Reminder if we ever add an AEAD mode with a different size */
             MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
             return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
         }
 
-        memcpy( ssl->transform_out->iv_enc + ssl->transform_out->fixed_ivlen,
-                             ssl->out_ctr, 8 );
-        memcpy( ssl->out_iv, ssl->out_ctr, 8 );
-
-        MBEDTLS_SSL_DEBUG_BUF( 4, "IV used", ssl->out_iv,
-                ssl->transform_out->ivlen - ssl->transform_out->fixed_ivlen );
+        MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (internal)",
+                                  iv, transform->ivlen );
+        MBEDTLS_SSL_DEBUG_BUF( 4, "IV used (transmitted)",
+                                  ssl->out_iv, explicit_ivlen );
 
         /*
-         * Fix pointer positions and message length with added IV
+         * Fix message length with added IV
          */
         enc_msg = ssl->out_msg;
         enc_msglen = ssl->out_msglen;
-        ssl->out_msglen += ssl->transform_out->ivlen -
-                           ssl->transform_out->fixed_ivlen;
+        ssl->out_msglen += explicit_ivlen;
 
         MBEDTLS_SSL_DEBUG_MSG( 3, ( "before encrypt: msglen = %d, "
-                            "including %d bytes of padding",
-                       ssl->out_msglen, 0 ) );
+                                    "including 0 bytes of padding",
+                                    ssl->out_msglen ) );
 
         /*
          * Encrypt and authenticate
          */
-        if( ( ret = mbedtls_cipher_auth_encrypt( &ssl->transform_out->cipher_ctx_enc,
-                                         ssl->transform_out->iv_enc,
-                                         ssl->transform_out->ivlen,
+        if( ( ret = mbedtls_cipher_auth_encrypt( &transform->cipher_ctx_enc,
+                                         iv, transform->ivlen,
                                          add_data, 13,
                                          enc_msg, enc_msglen,
                                          enc_msg, &olen,
@@ -1622,7 +1658,6 @@ static int ssl_encrypt_buf( mbedtls_ssl_context *ssl )
 
 static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
 {
-    size_t i;
     mbedtls_cipher_mode_t mode;
     int auth_done = 0;
 #if defined(SSL_SOME_MODES_USE_MAC)
@@ -1672,20 +1707,27 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
     }
     else
 #endif /* MBEDTLS_ARC4_C || MBEDTLS_CIPHER_NULL_CIPHER */
-#if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CCM_C)
+#if defined(MBEDTLS_GCM_C) || \
+    defined(MBEDTLS_CCM_C) || \
+    defined(MBEDTLS_CHACHAPOLY_C)
     if( mode == MBEDTLS_MODE_GCM ||
-        mode == MBEDTLS_MODE_CCM )
+        mode == MBEDTLS_MODE_CCM ||
+        mode == MBEDTLS_MODE_CHACHAPOLY )
     {
         int ret;
         size_t dec_msglen, olen;
         unsigned char *dec_msg;
         unsigned char *dec_msg_result;
         unsigned char add_data[13];
-        unsigned char taglen = ssl->transform_in->ciphersuite_info->flags &
+        unsigned char iv[12];
+        mbedtls_ssl_transform *transform = ssl->transform_in;
+        unsigned char taglen = transform->ciphersuite_info->flags &
                                MBEDTLS_CIPHERSUITE_SHORT_TAG ? 8 : 16;
-        size_t explicit_iv_len = ssl->transform_in->ivlen -
-                                 ssl->transform_in->fixed_ivlen;
+        size_t explicit_iv_len = transform->ivlen - transform->fixed_ivlen;
 
+        /*
+         * Compute and update sizes
+         */
         if( ssl->in_msglen < explicit_iv_len + taglen )
         {
             MBEDTLS_SSL_DEBUG_MSG( 1, ( "msglen (%d) < explicit_iv_len (%d) "
@@ -1699,6 +1741,9 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
         dec_msg_result = ssl->in_msg;
         ssl->in_msglen = dec_msglen;
 
+        /*
+         * Prepare additional authenticated data
+         */
         memcpy( add_data, ssl->in_ctr, 8 );
         add_data[8]  = ssl->in_msgtype;
         mbedtls_ssl_write_version( ssl->major_ver, ssl->minor_ver,
@@ -1706,23 +1751,43 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
         add_data[11] = ( ssl->in_msglen >> 8 ) & 0xFF;
         add_data[12] = ssl->in_msglen & 0xFF;
 
-        MBEDTLS_SSL_DEBUG_BUF( 4, "additional data used for AEAD",
-                       add_data, 13 );
+        MBEDTLS_SSL_DEBUG_BUF( 4, "additional data for AEAD", add_data, 13 );
 
-        memcpy( ssl->transform_in->iv_dec + ssl->transform_in->fixed_ivlen,
-                ssl->in_iv,
-                ssl->transform_in->ivlen - ssl->transform_in->fixed_ivlen );
+        /*
+         * Prepare IV
+         */
+        if( transform->ivlen == 12 && transform->fixed_ivlen == 4 )
+        {
+            /* GCM and CCM: fixed || explicit (transmitted) */
+            memcpy( iv, transform->iv_dec, transform->fixed_ivlen );
+            memcpy( iv + transform->fixed_ivlen, ssl->in_iv, 8 );
 
-        MBEDTLS_SSL_DEBUG_BUF( 4, "IV used", ssl->transform_in->iv_dec,
-                                     ssl->transform_in->ivlen );
+        }
+        else if( transform->ivlen == 12 && transform->fixed_ivlen == 12 )
+        {
+            /* ChachaPoly: fixed XOR sequence number */
+            unsigned char i;
+
+            memcpy( iv, transform->iv_dec, transform->fixed_ivlen );
+
+            for( i = 0; i < 8; i++ )
+                iv[i+4] ^= ssl->in_ctr[i];
+        }
+        else
+        {
+            /* Reminder if we ever add an AEAD mode with a different size */
+            MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
+            return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+        }
+
+        MBEDTLS_SSL_DEBUG_BUF( 4, "IV used", iv, transform->ivlen );
         MBEDTLS_SSL_DEBUG_BUF( 4, "TAG used", dec_msg + dec_msglen, taglen );
 
         /*
          * Decrypt and authenticate
          */
         if( ( ret = mbedtls_cipher_auth_decrypt( &ssl->transform_in->cipher_ctx_dec,
-                                         ssl->transform_in->iv_dec,
-                                         ssl->transform_in->ivlen,
+                                         iv, transform->ivlen,
                                          add_data, 13,
                                          dec_msg, dec_msglen,
                                          dec_msg_result, &olen,
@@ -1840,6 +1905,7 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
          */
         if( ssl->minor_ver >= MBEDTLS_SSL_MINOR_VERSION_2 )
         {
+            unsigned char i;
             dec_msglen -= ssl->transform_in->ivlen;
             ssl->in_msglen -= ssl->transform_in->ivlen;
 
@@ -1914,6 +1980,7 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
              */
             size_t pad_count = 0, real_count = 1;
             size_t padding_idx = ssl->in_msglen - padlen - 1;
+            size_t i;
 
             /*
              * Padding is guaranteed to be incorrect if:
@@ -2090,6 +2157,7 @@ static int ssl_decrypt_buf( mbedtls_ssl_context *ssl )
     else
 #endif
     {
+        unsigned char i;
         for( i = 8; i > ssl_ep_len( ssl ); i-- )
             if( ++ssl->in_ctr[i - 1] != 0 )
                 break;
diff --git a/tests/compat.sh b/tests/compat.sh
index d383cb478..bf65e5e61 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -42,6 +42,9 @@ if ( which $GNUTLS_CLI && which $GNUTLS_SERV ) >/dev/null 2>&1; then
             PEER_GNUTLS=""
         else
             PEER_GNUTLS=" GnuTLS"
+            if [ $MINOR -lt 4 ]; then
+                GNUTLS_MINOR_LT_FOUR='x'
+            fi
         fi
     fi
 else
@@ -58,7 +61,8 @@ FILTER=""
 # - RC4, single-DES: requires legacy OpenSSL/GnuTLS versions
 #   avoid plain DES but keep 3DES-EDE-CBC (mbedTLS), DES-CBC3 (OpenSSL)
 # - ARIA: not in default config.h + requires OpenSSL >= 1.1.1
-EXCLUDE='NULL\|DES-CBC-\|RC4\|ARCFOUR\|ARIA'
+# - ChachaPoly: requires OpenSSL >= 1.1.0
+EXCLUDE='NULL\|DES-CBC-\|RC4\|ARCFOUR\|ARIA\|CHACHA20-POLY1305'
 VERBOSE=""
 MEMCHECK=0
 PEERS="OpenSSL$PEER_GNUTLS mbedTLS"
@@ -437,6 +441,9 @@ add_common_ciphersuites()
 # NOTE: for some reason RSA-PSK doesn't work with OpenSSL,
 # so RSA-PSK ciphersuites need to go in other sections, see
 # https://github.com/ARMmbed/mbedtls/issues/1419
+#
+# ChachaPoly suites are here rather than in "common", as they were added in
+# GnuTLS in 3.5.0 and the CI only has 3.4.x so far.
 add_openssl_ciphersuites()
 {
     case $TYPE in
@@ -468,6 +475,7 @@ add_openssl_ciphersuites()
                     TLS-ECDH-ECDSA-WITH-AES-256-GCM-SHA384          \
                     TLS-ECDHE-ECDSA-WITH-ARIA-256-GCM-SHA384        \
                     TLS-ECDHE-ECDSA-WITH-ARIA-128-GCM-SHA256        \
+                    TLS-ECDHE-ECDSA-WITH-CHACHA20-POLY1305-SHA256   \
                     "
                 O_CIPHERS="$O_CIPHERS               \
                     ECDH-ECDSA-AES128-SHA256        \
@@ -476,6 +484,7 @@ add_openssl_ciphersuites()
                     ECDH-ECDSA-AES256-GCM-SHA384    \
                     ECDHE-ECDSA-ARIA256-GCM-SHA384  \
                     ECDHE-ECDSA-ARIA128-GCM-SHA256  \
+                    ECDHE-ECDSA-CHACHA20-POLY1305   \
                     "
             fi
             ;;
@@ -498,6 +507,8 @@ add_openssl_ciphersuites()
                     TLS-ECDHE-RSA-WITH-ARIA-128-GCM-SHA256          \
                     TLS-DHE-RSA-WITH-ARIA-128-GCM-SHA256            \
                     TLS-RSA-WITH-ARIA-128-GCM-SHA256                \
+                    TLS-DHE-RSA-WITH-CHACHA20-POLY1305-SHA256       \
+                    TLS-ECDHE-RSA-WITH-CHACHA20-POLY1305-SHA256     \
                     "
                 O_CIPHERS="$O_CIPHERS               \
                     ECDHE-ARIA256-GCM-SHA384        \
@@ -506,6 +517,8 @@ add_openssl_ciphersuites()
                     ECDHE-ARIA128-GCM-SHA256        \
                     DHE-RSA-ARIA128-GCM-SHA256      \
                     ARIA128-GCM-SHA256              \
+                    DHE-RSA-CHACHA20-POLY1305       \
+                    ECDHE-RSA-CHACHA20-POLY1305     \
                     "
             fi
             ;;
@@ -518,12 +531,18 @@ add_openssl_ciphersuites()
                     TLS-DHE-PSK-WITH-ARIA-128-GCM-SHA256            \
                     TLS-PSK-WITH-ARIA-256-GCM-SHA384                \
                     TLS-PSK-WITH-ARIA-128-GCM-SHA256                \
+                    TLS-PSK-WITH-CHACHA20-POLY1305-SHA256           \
+                    TLS-ECDHE-PSK-WITH-CHACHA20-POLY1305-SHA256     \
+                    TLS-DHE-PSK-WITH-CHACHA20-POLY1305-SHA256       \
                     "
                 O_CIPHERS="$O_CIPHERS               \
                     DHE-PSK-ARIA256-GCM-SHA384      \
                     DHE-PSK-ARIA128-GCM-SHA256      \
                     PSK-ARIA256-GCM-SHA384          \
                     PSK-ARIA128-GCM-SHA256          \
+                    DHE-PSK-CHACHA20-POLY1305       \
+                    ECDHE-PSK-CHACHA20-POLY1305     \
+                    PSK-CHACHA20-POLY1305           \
                     "
             fi
             ;;
@@ -545,12 +564,20 @@ add_gnutls_ciphersuites()
                     TLS-ECDHE-ECDSA-WITH-CAMELLIA-256-CBC-SHA384    \
                     TLS-ECDHE-ECDSA-WITH-CAMELLIA-128-GCM-SHA256    \
                     TLS-ECDHE-ECDSA-WITH-CAMELLIA-256-GCM-SHA384    \
+                    TLS-ECDHE-ECDSA-WITH-AES-128-CCM                \
+                    TLS-ECDHE-ECDSA-WITH-AES-256-CCM                \
+                    TLS-ECDHE-ECDSA-WITH-AES-128-CCM-8              \
+                    TLS-ECDHE-ECDSA-WITH-AES-256-CCM-8              \
                    "
                 G_CIPHERS="$G_CIPHERS                               \
                     +ECDHE-ECDSA:+CAMELLIA-128-CBC:+SHA256          \
                     +ECDHE-ECDSA:+CAMELLIA-256-CBC:+SHA384          \
                     +ECDHE-ECDSA:+CAMELLIA-128-GCM:+AEAD            \
                     +ECDHE-ECDSA:+CAMELLIA-256-GCM:+AEAD            \
+                    +ECDHE-ECDSA:+AES-128-CCM:+AEAD                 \
+                    +ECDHE-ECDSA:+AES-256-CCM:+AEAD                 \
+                    +ECDHE-ECDSA:+AES-128-CCM-8:+AEAD               \
+                    +ECDHE-ECDSA:+AES-256-CCM-8:+AEAD               \
                    "
             fi
             ;;
@@ -580,6 +607,14 @@ add_gnutls_ciphersuites()
                     TLS-DHE-RSA-WITH-CAMELLIA-256-GCM-SHA384    \
                     TLS-RSA-WITH-CAMELLIA-128-GCM-SHA256        \
                     TLS-RSA-WITH-CAMELLIA-256-GCM-SHA384        \
+                    TLS-RSA-WITH-AES-128-CCM                    \
+                    TLS-RSA-WITH-AES-256-CCM                    \
+                    TLS-DHE-RSA-WITH-AES-128-CCM                \
+                    TLS-DHE-RSA-WITH-AES-256-CCM                \
+                    TLS-RSA-WITH-AES-128-CCM-8                  \
+                    TLS-RSA-WITH-AES-256-CCM-8                  \
+                    TLS-DHE-RSA-WITH-AES-128-CCM-8              \
+                    TLS-DHE-RSA-WITH-AES-256-CCM-8              \
                     "
                 G_CIPHERS="$G_CIPHERS                           \
                     +ECDHE-RSA:+CAMELLIA-128-CBC:+SHA256        \
@@ -594,6 +629,14 @@ add_gnutls_ciphersuites()
                     +DHE-RSA:+CAMELLIA-256-GCM:+AEAD            \
                     +RSA:+CAMELLIA-128-GCM:+AEAD                \
                     +RSA:+CAMELLIA-256-GCM:+AEAD                \
+                    +RSA:+AES-128-CCM:+AEAD                     \
+                    +RSA:+AES-256-CCM:+AEAD                     \
+                    +RSA:+AES-128-CCM-8:+AEAD                   \
+                    +RSA:+AES-256-CCM-8:+AEAD                   \
+                    +DHE-RSA:+AES-128-CCM:+AEAD                 \
+                    +DHE-RSA:+AES-256-CCM:+AEAD                 \
+                    +DHE-RSA:+AES-128-CCM-8:+AEAD               \
+                    +DHE-RSA:+AES-256-CCM-8:+AEAD               \
                     "
             fi
             ;;
@@ -665,6 +708,14 @@ add_gnutls_ciphersuites()
                     TLS-PSK-WITH-AES-256-GCM-SHA384             \
                     TLS-DHE-PSK-WITH-AES-128-GCM-SHA256         \
                     TLS-DHE-PSK-WITH-AES-256-GCM-SHA384         \
+                    TLS-PSK-WITH-AES-128-CCM                    \
+                    TLS-PSK-WITH-AES-256-CCM                    \
+                    TLS-DHE-PSK-WITH-AES-128-CCM                \
+                    TLS-DHE-PSK-WITH-AES-256-CCM                \
+                    TLS-PSK-WITH-AES-128-CCM-8                  \
+                    TLS-PSK-WITH-AES-256-CCM-8                  \
+                    TLS-DHE-PSK-WITH-AES-128-CCM-8              \
+                    TLS-DHE-PSK-WITH-AES-256-CCM-8              \
                     TLS-RSA-PSK-WITH-CAMELLIA-128-GCM-SHA256    \
                     TLS-RSA-PSK-WITH-CAMELLIA-256-GCM-SHA384    \
                     TLS-PSK-WITH-CAMELLIA-128-GCM-SHA256        \
@@ -695,6 +746,14 @@ add_gnutls_ciphersuites()
                     +PSK:+AES-256-GCM:+AEAD                     \
                     +DHE-PSK:+AES-128-GCM:+AEAD                 \
                     +DHE-PSK:+AES-256-GCM:+AEAD                 \
+                    +PSK:+AES-128-CCM:+AEAD                     \
+                    +PSK:+AES-256-CCM:+AEAD                     \
+                    +DHE-PSK:+AES-128-CCM:+AEAD                 \
+                    +DHE-PSK:+AES-256-CCM:+AEAD                 \
+                    +PSK:+AES-128-CCM-8:+AEAD                   \
+                    +PSK:+AES-256-CCM-8:+AEAD                   \
+                    +DHE-PSK:+AES-128-CCM-8:+AEAD               \
+                    +DHE-PSK:+AES-256-CCM-8:+AEAD               \
                     +RSA-PSK:+CAMELLIA-128-GCM:+AEAD            \
                     +RSA-PSK:+CAMELLIA-256-GCM:+AEAD            \
                     +PSK:+CAMELLIA-128-GCM:+AEAD                \
@@ -737,10 +796,6 @@ add_mbedtls_ciphersuites()
                 M_CIPHERS="$M_CIPHERS                               \
                     TLS-ECDH-ECDSA-WITH-CAMELLIA-128-GCM-SHA256     \
                     TLS-ECDH-ECDSA-WITH-CAMELLIA-256-GCM-SHA384     \
-                    TLS-ECDHE-ECDSA-WITH-AES-128-CCM                \
-                    TLS-ECDHE-ECDSA-WITH-AES-256-CCM                \
-                    TLS-ECDHE-ECDSA-WITH-AES-128-CCM-8              \
-                    TLS-ECDHE-ECDSA-WITH-AES-256-CCM-8              \
                     TLS-ECDHE-ECDSA-WITH-ARIA-256-CBC-SHA384        \
                     TLS-ECDHE-ECDSA-WITH-ARIA-128-CBC-SHA256        \
                     TLS-ECDH-ECDSA-WITH-ARIA-256-GCM-SHA384         \
@@ -755,14 +810,6 @@ add_mbedtls_ciphersuites()
             if [ `minor_ver "$MODE"` -ge 3 ]
             then
                 M_CIPHERS="$M_CIPHERS                               \
-                    TLS-RSA-WITH-AES-128-CCM                        \
-                    TLS-RSA-WITH-AES-256-CCM                        \
-                    TLS-DHE-RSA-WITH-AES-128-CCM                    \
-                    TLS-DHE-RSA-WITH-AES-256-CCM                    \
-                    TLS-RSA-WITH-AES-128-CCM-8                      \
-                    TLS-RSA-WITH-AES-256-CCM-8                      \
-                    TLS-DHE-RSA-WITH-AES-128-CCM-8                  \
-                    TLS-DHE-RSA-WITH-AES-256-CCM-8                  \
                     TLS-ECDHE-RSA-WITH-ARIA-256-CBC-SHA384          \
                     TLS-DHE-RSA-WITH-ARIA-256-CBC-SHA384            \
                     TLS-ECDHE-RSA-WITH-ARIA-128-CBC-SHA256          \
@@ -789,14 +836,6 @@ add_mbedtls_ciphersuites()
             if [ `minor_ver "$MODE"` -ge 3 ]
             then
                 M_CIPHERS="$M_CIPHERS                               \
-                    TLS-PSK-WITH-AES-128-CCM                        \
-                    TLS-PSK-WITH-AES-256-CCM                        \
-                    TLS-DHE-PSK-WITH-AES-128-CCM                    \
-                    TLS-DHE-PSK-WITH-AES-256-CCM                    \
-                    TLS-PSK-WITH-AES-128-CCM-8                      \
-                    TLS-PSK-WITH-AES-256-CCM-8                      \
-                    TLS-DHE-PSK-WITH-AES-128-CCM-8                  \
-                    TLS-DHE-PSK-WITH-AES-256-CCM-8                  \
                     TLS-RSA-PSK-WITH-ARIA-256-CBC-SHA384            \
                     TLS-RSA-PSK-WITH-ARIA-128-CBC-SHA256            \
                     TLS-PSK-WITH-ARIA-256-CBC-SHA384                \
@@ -807,6 +846,7 @@ add_mbedtls_ciphersuites()
                     TLS-ECDHE-PSK-WITH-ARIA-128-CBC-SHA256          \
                     TLS-DHE-PSK-WITH-ARIA-256-CBC-SHA384            \
                     TLS-DHE-PSK-WITH-ARIA-128-CBC-SHA256            \
+                    TLS-RSA-PSK-WITH-CHACHA20-POLY1305-SHA256       \
                     "
             fi
             ;;
@@ -842,10 +882,17 @@ setup_arguments()
             exit 1;
     esac
 
+    # GnuTLS < 3.4 will choke if we try to allow CCM-8
+    if [ -z "${GNUTLS_MINOR_LT_FOUR-}" ]; then
+        G_PRIO_CCM="+AES-256-CCM-8:+AES-128-CCM-8:"
+    else
+        G_PRIO_CCM=""
+    fi
+
     M_SERVER_ARGS="server_port=$PORT server_addr=0.0.0.0 force_version=$MODE arc4=1"
     O_SERVER_ARGS="-accept $PORT -cipher NULL,ALL -$MODE -dhparam data_files/dhparams.pem"
     G_SERVER_ARGS="-p $PORT --http $G_MODE"
-    G_SERVER_PRIO="NORMAL:+ARCFOUR-128:+NULL:+MD5:+PSK:+DHE-PSK:+ECDHE-PSK:+RSA-PSK:-VERS-TLS-ALL:$G_PRIO_MODE"
+    G_SERVER_PRIO="NORMAL:${G_PRIO_CCM}+ARCFOUR-128:+NULL:+MD5:+PSK:+DHE-PSK:+ECDHE-PSK:+RSA-PSK:-VERS-TLS-ALL:$G_PRIO_MODE"
 
     # with OpenSSL 1.0.1h, -www, -WWW and -HTTP break DTLS handshakes
     if is_dtls "$MODE"; then
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 1e1cf3597..82a8bddc6 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -565,8 +565,8 @@ if_build_succeeded tests/ssl-opt.sh -f 'Default\|ECJPAKE\|SSL async private'
 msg "test: compat.sh RC4, DES & NULL (full config)" # ~ 2 min
 if_build_succeeded env OPENSSL_CMD="$OPENSSL_LEGACY" GNUTLS_CLI="$GNUTLS_LEGACY_CLI" GNUTLS_SERV="$GNUTLS_LEGACY_SERV" tests/compat.sh -e '3DES\|DES-CBC3' -f 'NULL\|DES\|RC4\|ARCFOUR'
 
-msg "test: compat.sh ARIA"
-if_build_succeeded env OPENSSL_CMD="$OPENSSL_NEXT" tests/compat.sh -e '^$' -f 'ARIA'
+msg "test: compat.sh ARIA + ChachaPoly"
+if_build_succeeded env OPENSSL_CMD="$OPENSSL_NEXT" tests/compat.sh -e '^$' -f 'ARIA\|CHACHA'
 
 msg "build: make, full config + DEPRECATED_WARNING, gcc -O" # ~ 30s
 cleanup
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 9fc91c722..0f6153565 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -742,7 +742,7 @@ run_test    "Default" \
             "$P_CLI" \
             0 \
             -s "Protocol is TLSv1.2" \
-            -s "Ciphersuite is TLS-ECDHE-ECDSA-WITH-AES-256-GCM-SHA384" \
+            -s "Ciphersuite is TLS-ECDHE-RSA-WITH-CHACHA20-POLY1305-SHA256" \
             -s "client hello v3, signature_algorithm ext: 6" \
             -s "ECDHE curve: secp521r1" \
             -S "error" \
@@ -753,20 +753,14 @@ run_test    "Default, DTLS" \
             "$P_CLI dtls=1" \
             0 \
             -s "Protocol is DTLSv1.2" \
-            -s "Ciphersuite is TLS-ECDHE-ECDSA-WITH-AES-256-GCM-SHA384"
+            -s "Ciphersuite is TLS-ECDHE-RSA-WITH-CHACHA20-POLY1305-SHA256"
 
 # Test current time in ServerHello
 requires_config_enabled MBEDTLS_HAVE_TIME
-run_test    "Default, ServerHello contains gmt_unix_time" \
+run_test    "ServerHello contains gmt_unix_time" \
             "$P_SRV debug_level=3" \
             "$P_CLI debug_level=3" \
             0 \
-            -s "Protocol is TLSv1.2" \
-            -s "Ciphersuite is TLS-ECDHE-ECDSA-WITH-AES-256-GCM-SHA384" \
-            -s "client hello v3, signature_algorithm ext: 6" \
-            -s "ECDHE curve: secp521r1" \
-            -S "error" \
-            -C "error" \
             -f "check_server_hello_time" \
             -F "check_server_hello_time"