Improve mariabackup SST script compliance with native MariaDB SSL practices

and configuration.

1. Pass joiner's authentication information to donor together with address
   in State Transfer Request. This allows joiner to authenticate donor on
   connection. Previously joiner would accept data from anywhere.

2. Deprecate custom SSL configuration variables tca, tcert and tkey in favor
   of more familiar ssl-ca, ssl-cert and ssl-key. For backward compatibility
   tca, tcert and tkey are still supported.

3. Allow falling back to server-wide SSL configuration in [mysqld] if no SSL
   configuration is found in [sst] section of the config file.

4. Introduce ssl-mode variable in [sst] section that takes standard values
   and has following effects:
    - old-style SSL configuration present in [sst]: no effect
      otherwise:
    - ssl-mode=DISABLED or absent: retains old, backward compatible behavior
      and ignores any other SSL configuration
    - ssl-mode=VERIFY*: verify joiner's certificate and CN on donor,
                        verify donor's secret on joiner
                        (passed to donor via State Transfer Request)
                        BACKWARD INCOMPATIBLE BEHAVIOR
    - anything else enables new SSL configuration convetions but does not
      require verification

    ssl-mode should be set to VERIFY only in a fully upgraded cluster.

    Examples:

    [mysqld]
    ssl-cert=/path/to/cert
    ssl-key=/path/to/key
    ssl-ca=/path/to/ca

    [sst]

     -- server-wide SSL configuration is ignored, SST does not use SSL

    [mysqld]
    ssl-cert=/path/to/cert
    ssl-key=/path/to/key
    ssl-ca=/path/to/ca

    [sst]
    ssl-mode=REQUIRED

     -- use server-wide SSL configuration for SST but don't attempt to
        verify the peer identity

    [sst]
    ssl-cert=/path/to/cert
    ssl-key=/path/to/key
    ssl-ca=/path/to/ca
    ssl-mode=VERIFY_CA

     -- use SST-specific SSL configuration for SST and require verification
        on both sides

8 files changed, 259 insertions, 75 deletions

diff --git a/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key.result b/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key.result
index 990e0a29506..8048cafecd8 100644
--- a/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key.result
+++ b/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key.result
@@ -1,3 +1,4 @@
 SELECT 1;
 1
 1
+include/assert_grep.inc [Using openssl based encryption with socat]
diff --git a/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key_server.result b/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key_server.result
new file mode 100644
index 00000000000..8048cafecd8
--- /dev/null
+++ b/mysql-test/suite/galera/r/galera_sst_mariabackup_encrypt_with_key_server.result
@@ -0,0 +1,4 @@
+SELECT 1;
+1
+1
+include/assert_grep.inc [Using openssl based encryption with socat]
diff --git a/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key.test b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key.test
index 4449ea43c43..523d44102dd 100644
--- a/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key.test
+++ b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key.test
@@ -1,6 +1,8 @@
 #
-# This test checks that key and cert encryption options can be passed to mariabackup via the my.cnf file
-# Initial SST happens via mariabackup, so there is not much to do in the body of the test
+# This test checks that key and cert encryption options can be passed to
+# mariabackup via the my.cnf file
+# Initial SST happens via mariabackup, so there is not much to do in the body
+# of the test
 #
 
 --source include/big_test.inc
@@ -12,3 +14,11 @@ SELECT 1;
 
 --let $wait_condition = SELECT VARIABLE_VALUE = 2 FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_cluster_size';
 --source include/wait_condition.inc
+
+# Confirm that transfer was SSL-encrypted
+--let $assert_text = Using openssl based encryption with socat
+--let $assert_select = Using openssl based encryption with socat: with key and crt
+--let $assert_count = 1
+--let $assert_file = $MYSQLTEST_VARDIR/log/mysqld.1.err
+--let $assert_only_after = CURRENT_TEST
+--source include/assert_grep.inc
diff --git a/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.cnf b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.cnf
new file mode 100644
index 00000000000..12fca48e065
--- /dev/null
+++ b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.cnf
@@ -0,0 +1,13 @@
+!include ../galera_2nodes.cnf
+
+[mysqld]
+wsrep_sst_method=mariabackup
+wsrep_sst_auth="root:"
+wsrep_debug=ON
+
+ssl-cert=@ENV.MYSQL_TEST_DIR/std_data/client-cert.pem
+ssl-key=@ENV.MYSQL_TEST_DIR/std_data/client-key.pem
+ssl-ca=@ENV.MYSQL_TEST_DIR/std_data/cacert.pem
+
+[sst]
+ssl-mode=VERIFY_CA
\ No newline at end of file
diff --git a/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.test b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.test
new file mode 100644
index 00000000000..19ebd0cf51e
--- /dev/null
+++ b/mysql-test/suite/galera/t/galera_sst_mariabackup_encrypt_with_key_server.test
@@ -0,0 +1,25 @@
+#
+# This test checks that if SST SSL is not explicitly donfigured mariabackup SST
+# uses server SSL configuration if present.
+# Initial SST happens via mariabackup, so there is not much to do in the body
+# of the test
+#
+
+--source include/big_test.inc
+--source include/galera_cluster.inc
+--source include/have_innodb.inc
+--source include/have_mariabackup.inc
+--source include/have_ssl_communication.inc
+
+SELECT 1;
+
+--let $wait_condition = SELECT VARIABLE_VALUE = 2 FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'wsrep_cluster_size';
+--source include/wait_condition.inc
+
+# Confirm that transfer was SSL-encrypted
+--let $assert_text = Using openssl based encryption with socat
+--let $assert_select = Using openssl based encryption with socat: with key and c
+--let $assert_count = 1
+--let $assert_file = $MYSQLTEST_VARDIR/log/mysqld.1.err
+--let $assert_only_after = CURRENT_TEST
+--source include/assert_grep.inc
diff --git a/scripts/wsrep_sst_common.sh b/scripts/wsrep_sst_common.sh
index f5adf0b0fd8..a6f439b5348 100644
--- a/scripts/wsrep_sst_common.sh
+++ b/scripts/wsrep_sst_common.sh
@@ -25,6 +25,7 @@ WSREP_SST_OPT_DATA=""
 WSREP_SST_OPT_AUTH=${WSREP_SST_OPT_AUTH:-}
 WSREP_SST_OPT_USER=${WSREP_SST_OPT_USER:-}
 WSREP_SST_OPT_PSWD=${WSREP_SST_OPT_PSWD:-}
+WSREP_SST_OPT_REMOTE_AUTH=${WSREP_SST_OPT_REMOTE_AUTH:-}
 WSREP_SST_OPT_DEFAULT=""
 WSREP_SST_OPT_EXTRA_DEFAULT=""
 WSREP_SST_OPT_SUFFIX_DEFAULT=""
@@ -34,6 +35,7 @@ INNODB_DATA_HOME_DIR_ARG=""
 INNODB_LOG_GROUP_HOME_ARG=""
 INNODB_UNDO_DIR_ARG=""
 LOG_BIN_ARG=""
+readonly WSREP_SST_OPT_REMOTE_AUTH
 
 while [ $# -gt 0 ]; do
 case "$1" in
@@ -121,7 +123,8 @@ case "$1" in
         WSREP_SST_OPT_BYPASS=1
         ;;
     '--datadir')
-        readonly WSREP_SST_OPT_DATA="$2"
+        # strip trailing '/'
+        readonly WSREP_SST_OPT_DATA="${2%/}"
         shift
         ;;
     '--innodb-data-home-dir')
@@ -320,12 +323,22 @@ readonly WSREP_SST_OPT_AUTH
 # Splitting AUTH into potential user:password pair
 if ! wsrep_auth_not_set
 then
-    WSREP_SST_OPT_USER="${WSREP_SST_OPT_AUTH%%:*}"
+    WSREP_SST_OPT_USER="${WSREP_SST_OPT_AUTH%:*}"
     WSREP_SST_OPT_PSWD="${WSREP_SST_OPT_AUTH##*:}"
 fi
 readonly WSREP_SST_OPT_USER
 readonly WSREP_SST_OPT_PSWD
 
+if [ -n "$WSREP_SST_OPT_REMOTE_AUTH" ]
+then
+    # Split auth string at the last ':'
+    readonly WSREP_SST_OPT_REMOTE_USER="${WSREP_SST_OPT_REMOTE_AUTH%:*}"
+    readonly WSREP_SST_OPT_REMOTE_PSWD="${WSREP_SST_OPT_REMOTE_AUTH##*:}"
+else
+    readonly WSREP_SST_OPT_REMOTE_USER=
+    readonly WSREP_SST_OPT_REMOTE_PSWD=
+fi
+
 if [ -n "${WSREP_SST_OPT_DATA:-}" ]
 then
     SST_PROGRESS_FILE="$WSREP_SST_OPT_DATA/sst_in_progress"
@@ -385,6 +398,19 @@ wsrep_check_programs()
     return $ret
 }
 
+# Generate a string equivalent to 16 random bytes
+wsrep_gen_secret()
+{
+    if [ -x /usr/bin/openssl ]
+    then
+        echo `/usr/bin/openssl rand -hex 16`
+    else
+        printf "%04x%04x%04x%04x%04x%04x%04x%04x" \
+                $RANDOM $RANDOM $RANDOM $RANDOM   \
+                $RANDOM $RANDOM $RANDOM $RANDOM
+    fi
+}
+
 #
 # user can specify mariabackup specific settings that will be used during sst
 # process like encryption, etc.....
@@ -396,14 +422,22 @@ wsrep_check_programs()
 parse_cnf()
 {
     local group=$1
-    local var=$2
+    local var=${2//_/-} # normalize variable name by replacing all '_' with '-'
     local reval=""
 
-    # normalize the variable names specified in cnf file (user can use _ or - for example log-bin or log_bin)
+    # first normalize output variable names specified in cnf file:
+    # user can use _ or - (for example log-bin or log_bin) and/or prefix
+    # variable with --loose-
     # then search for needed variable
     # finally get the variable value (if variables has been specified multiple time use the last value only)
 
-    reval=$($MY_PRINT_DEFAULTS "${group}" | awk -v var="${var}" 'BEGIN { OFS=FS="=" } { gsub(/_/,"-",$1); if ( $1=="--"var) lastval=substr($0,length($1)+2) } END { print lastval}')
+    reval=$($MY_PRINT_DEFAULTS "${group}" | \
+            awk -v var="${var}" 'BEGIN { OFS=FS="=" } \
+                                       { sub(/^--loose/,"-",$0); \
+                                         gsub(/_/,"-",$1); \
+                                         if ( $1=="--"var) \
+                                             lastval=substr($0,length($1)+2) } \
+                                 END { print lastval}')
 
     # use default if we haven't found a value
     if [ -z "$reval" ]; then
diff --git a/scripts/wsrep_sst_mariabackup.sh b/scripts/wsrep_sst_mariabackup.sh
index 231cf6e3702..f54afb878b5 100644
--- a/scripts/wsrep_sst_mariabackup.sh
+++ b/scripts/wsrep_sst_mariabackup.sh
@@ -37,6 +37,7 @@ REMOTEIP=""
 tcert=""
 tpem=""
 tkey=""
+tmode="DISABLED"
 sockopt=""
 progress=""
 ttime=0
@@ -72,6 +73,8 @@ xtmpdir=""
 scomp=""
 sdecomp=""
 
+readonly SECRET_TAG="secret"
+
 # Required for backup locks
 # For backup locks it is 1 sent by joiner
 # 5.6.21 PXC and later can't donate to an older joiner
@@ -264,24 +267,30 @@ get_transfer()
                 exit 22
             fi
             stagemsg+="-OpenSSL-Encrypted-3"
-            if [[ "$WSREP_SST_OPT_ROLE"  == "joiner" ]];then
-                if [[ -z $tcert ]];then
+            if [[ -z $tcert ]];then
+                # no verification
+                if [[ "$WSREP_SST_OPT_ROLE"  == "joiner" ]];then
                     wsrep_log_info "Decrypting with cert=${tpem}, key=${tkey}, verify=0"
                     tcmd="socat -u openssl-listen:${TSST_PORT},reuseaddr,cert=${tpem},key=${tkey},verify=0${sockopt} stdio"
                 else
-                    wsrep_log_info "Decrypting with cert=${tpem}, key=${tkey}, cafile=${tcert}"
-                    tcmd="socat -u openssl-listen:${TSST_PORT},reuseaddr,cert=${tpem},key=${tkey},cafile=${tcert}${sockopt} stdio"
-                fi
-            else
-                if [[ -z $tcert ]];then
                     wsrep_log_info "Encrypting with cert=${tpem}, key=${tkey}, verify=0"
                     tcmd="socat -u stdio openssl-connect:${REMOTEIP}:${TSST_PORT},cert=${tpem},key=${tkey},verify=0${sockopt}"
+                fi
+            else
+                # CA verification
+                if [[ "$WSREP_SST_OPT_ROLE"  == "joiner" ]];then
+                    wsrep_log_info "Decrypting with cert=${tpem}, key=${tkey}, cafile=${tcert}"
+                    tcmd="socat -u openssl-listen:${TSST_PORT},reuseaddr,cert=${tpem},key=${tkey},cafile=${tcert}${sockopt} stdio"
                 else
+                    if [ -n "$WSREP_SST_OPT_REMOTE_USER" ]; then
+                        CN_option=",commonname=$WSREP_SST_OPT_REMOTE_USER"
+                    else
+                        CN_option=""
+                    fi
                     wsrep_log_info "Encrypting with cert=${tpem}, key=${tkey}, cafile=${tcert}"
-                    tcmd="socat -u stdio openssl-connect:${REMOTEIP}:${TSST_PORT},cert=${tpem},key=${tkey},cafile=${tcert}${sockopt}"
+                    tcmd="socat -u stdio openssl-connect:${REMOTEIP}:${TSST_PORT},cert=${tpem},key=${tkey},cafile=${tcert}${CN_option}${sockopt}"
                 fi
             fi
-
         else 
             if [[ "$WSREP_SST_OPT_ROLE"  == "joiner" ]];then
                 tcmd="socat -u TCP-LISTEN:${TSST_PORT},reuseaddr${sockopt} stdio"
@@ -290,7 +299,6 @@ get_transfer()
             fi
         fi
     fi
-
 }
 
 parse_cnf()
@@ -298,10 +306,17 @@ parse_cnf()
     local group=$1
     local var=$2
     # print the default settings for given group using my_print_default.
+    # remove possible 'loose' variable name prefix
     # normalize the variable names specified in cnf file (user can use _ or - for example log-bin or log_bin)
     # then grep for needed variable
     # finally get the variable value (if variables has been specified multiple time use the last value only)
-    reval=$($MY_PRINT_DEFAULTS $group | awk -F= '{if ($1 ~ /_/) { gsub(/_/,"-",$1); print $1"="$2 } else { print $0 }}' | grep -- "--$var=" | cut -d= -f2- | tail -1)
+    reval=$($MY_PRINT_DEFAULTS $group | \
+            awk -F= '{ sub(/^--loose/,"-",$0); \
+                       if ($1 ~ /_/) \
+                           { gsub(/_/,"-",$1); print $1"="$2 } \
+                       else \
+                           { print $0 }}' | \
+            grep -- "--$var=" | cut -d= -f2- | tail -1)
     if [[ -z $reval ]];then 
         [[ -n $3 ]] && reval=$3
     fi
@@ -351,6 +366,24 @@ adjust_progress()
     fi
 }
 
+check_server_ssl_config()
+{
+    local section=$1
+    tcert=$(parse_cnf $section ssl-ca "")
+    tpem=$(parse_cnf $section ssl-cert "")
+    tkey=$(parse_cnf $section ssl-key "")
+    if [ 0 -eq $encrypt -a -n "$tpem" -a -n "$tkey" ]
+    then
+         encrypt=3 # enable cert/key SSL encyption
+
+         # avoid CA verification if not set explicitly:
+         # nodes may happen to have different CA if self-generated
+         # zeroing up tcert does the trick
+         local mode=$(parse_cnf SST ssl-mode "")
+         [[ ${tmode} = *VERIFY* ]] || tcert=""
+    fi
+}
+
 read_cnf()
 {
     sfmt=$(parse_cnf sst streamfmt "xbstream")
@@ -359,6 +392,26 @@ read_cnf()
     tpem=$(parse_cnf sst tcert "")
     tkey=$(parse_cnf sst tkey "")
     encrypt=$(parse_cnf sst encrypt 0)
+    tmode=$(parse_cnf sst ssl-mode "DISABLED" | tr [:lower:] [:upper:])
+
+    if [ -z "$tpem" -a -z "$tkey" -a -z "$tcert" ]
+    then # no old-style SSL config in [sst]
+        if [ "$tmode" != "DISABLED" ]
+        then # backward-incompatible behavior
+            check_server_ssl_config "sst"
+            if [ -z "$tpem" -a -z "$tkey" -a -z "$tcert" ]
+            then # no new-stype SSL config in [sst], try server-wide SSL config
+                check_server_ssl_config "mysqld.$WSREP_SST_OPT_SUFFIX_VALUE"
+                if [ -z "$tpem" -a -z "$tkey" -a -z "$tcert" ]
+                then
+                    check_server_ssl_config "mysqld"
+                fi
+            fi
+        fi
+    fi
+    wsrep_log_info "SSL configuration: CA='"$tcert"', CERT='"$tpem"'," \
+                   "KEY='"$tkey"', MODE='"$tmode"', encrypt="$encrypt
+
     sockopt=$(parse_cnf sst sockopt "")
     progress=$(parse_cnf sst progress "")
     rebuild=$(parse_cnf sst rebuild 0)
@@ -404,7 +457,7 @@ read_cnf()
 
     if [[ $encrypt -eq 1 ]]; then
         wsrep_log_error "Xtrabackup-based encryption is currently not" \
-            "supported with MariaBackup"
+                        "supported with MariaBackup"
         exit 2
     fi
 }
@@ -631,8 +684,8 @@ recv_joiner()
     popd 1>/dev/null 
 
     if [[ ${RC[0]} -eq 124 ]];then 
-        wsrep_log_error "Possible timeout in receiving first data from "
-	                "donor in gtid stage: exit codes: ${RC[@]}"
+        wsrep_log_error "Possible timeout in receiving first data from " \
+                        "donor in gtid stage: exit codes: ${RC[@]}"
         exit 32
     fi
 
@@ -644,12 +697,27 @@ recv_joiner()
         fi
     done
 
-    if [[ $checkf -eq 1 && ! -r "${MAGIC_FILE}" ]];then
-        # this message should cause joiner to abort
-        wsrep_log_error "xtrabackup process ended without creating '${MAGIC_FILE}'"
-        wsrep_log_info "Contents of datadir" 
-        wsrep_log_info "$(ls -l ${dir}/*)"
-        exit 32
+    if [[ $checkf -eq 1 ]]; then
+        if [[ ! -r "${MAGIC_FILE}" ]];then
+            # this message should cause joiner to abort
+            wsrep_log_error "receiving process ended without creating " \
+                            "'${MAGIC_FILE}'"
+            wsrep_log_info "Contents of datadir" 
+            wsrep_log_info "$(ls -l ${dir}/*)"
+            exit 32
+        fi
+
+        # check donor supplied secret
+        SECRET=$(grep "$SECRET_TAG " ${MAGIC_FILE} 2>/dev/null | cut -d ' ' -f 2)
+        if [[ $SECRET != $MY_SECRET ]]; then
+            wsrep_log_error "Donor does not know my secret!"
+            wsrep_log_info "Donor:'$SECRET', my:'$MY_SECRET'"
+            exit 32
+        fi
+
+        # remove secret from magic file
+        grep -v "$SECRET_TAG " ${MAGIC_FILE} > ${MAGIC_FILE}.new
+        mv ${MAGIC_FILE}.new ${MAGIC_FILE}
     fi
 }
 
@@ -665,10 +733,9 @@ send_donor()
     set -e
     popd 1>/dev/null 
 
-
     for ecode in "${RC[@]}";do 
         if [[ $ecode -ne 0 ]];then 
-            wsrep_log_error "Error while getting data from donor node: " \
+            wsrep_log_error "Error while sending data to joiner node: " \
                             "exit codes: ${RC[@]}"
             exit 32
         fi
@@ -891,6 +958,11 @@ then
         # (separated by a space).
         echo "${WSREP_SST_OPT_GTID} ${WSREP_SST_OPT_GTID_DOMAIN_ID}" > "${MAGIC_FILE}"
 
+        if [[ -n ${WSREP_SST_OPT_REMOTE_PSWD} ]]; then
+            # Let joiner know that we know its secret
+            echo "$SECRET_TAG ${WSREP_SST_OPT_REMOTE_PSWD}" >> ${MAGIC_FILE}
+        fi
+
         ttcmd="$tcmd"
 
         if [[ $encrypt -eq 1 ]];then
@@ -1003,7 +1075,6 @@ then
 
     stagemsg="Joiner-Recv"
 
-
     sencrypted=1
     nthreads=1
 
@@ -1025,7 +1096,26 @@ then
         fi
     fi
 
-    wait_for_listen ${SST_PORT} ${ADDR} ${MODULE} &
+    if [[ "$tmode" = *"VERIFY"* ]]
+    then # backward-incompatible behavior
+        if [ -n "$tpem" ]
+        then
+            # find out my Common Name
+            wsrep_check_programs openssl
+            CN=$(openssl x509 -noout -subject -in $tpem | \
+                 tr "," "\n" | grep "CN =" | cut -d= -f2 | sed s/^\ // | \
+                 sed s/\ %//)
+        else
+            CN=""
+        fi
+        MY_SECRET=$(wsrep_gen_secret)
+        # Add authentication data to address
+        ADDR="$CN:$MY_SECRET@$ADDR"
+    else
+        MY_SECRET="" # for check down in recv_joiner()
+    fi # tmode == *VERIFY*
+
+    wait_for_listen ${SST_PORT} "${ADDR}" ${MODULE} &
 
     trap sig_joiner_cleanup HUP PIPE INT TERM
     trap cleanup_joiner EXIT
diff --git a/sql/wsrep_sst.cc b/sql/wsrep_sst.cc
index f4092b9b8a7..38560c7c663 100644
--- a/sql/wsrep_sst.cc
+++ b/sql/wsrep_sst.cc
@@ -637,49 +637,30 @@ err:
   return NULL;
 }
 
-#define WSREP_SST_AUTH_ENV "WSREP_SST_OPT_AUTH"
+#define WSREP_SST_AUTH_ENV        "WSREP_SST_OPT_AUTH"
+#define WSREP_SST_REMOTE_AUTH_ENV "WSREP_SST_OPT_REMOTE_AUTH"
+#define DATA_HOME_DIR_ENV         "INNODB_DATA_HOME_DIR"
 
-static int sst_append_auth_env(wsp::env& env, const char* sst_auth)
+static int sst_append_env_var(wsp::env&   env,
+                              const char* const var,
+                              const char* const val)
 {
-  int const sst_auth_size= strlen(WSREP_SST_AUTH_ENV) + 1 /* = */
-    + (sst_auth ? strlen(sst_auth) : 0) + 1 /* \0 */;
+  int const env_str_size= strlen(var) + 1 /* = */
+                          + (val ? strlen(val) : 0) + 1 /* \0 */;
 
-  wsp::string sst_auth_str(sst_auth_size); // for automatic cleanup on return
-  if (!sst_auth_str()) return -ENOMEM;
+  wsp::string env_str(env_str_size); // for automatic cleanup on return
+  if (!env_str()) return -ENOMEM;
 
-  int ret= snprintf(sst_auth_str(), sst_auth_size, "%s=%s",
-                    WSREP_SST_AUTH_ENV, sst_auth ? sst_auth : "");
+  int ret= snprintf(env_str(), env_str_size, "%s=%s", var, val ? val : "");
 
-  if (ret < 0 || ret >= sst_auth_size)
+  if (ret < 0 || ret >= env_str_size)
   {
-    WSREP_ERROR("sst_append_auth_env(): snprintf() failed: %d", ret);
+    WSREP_ERROR("sst_append_env_var(): snprintf(%s=%s) failed: %d",
+                var, val, ret);
     return (ret < 0 ? ret : -EMSGSIZE);
   }
 
-  env.append(sst_auth_str());
-  return -env.error();
-}
-
-#define DATA_HOME_DIR_ENV "INNODB_DATA_HOME_DIR"
-
-static int sst_append_data_dir(wsp::env& env, const char* data_dir)
-{
-  int const data_dir_size= strlen(DATA_HOME_DIR_ENV) + 1 /* = */
-    + (data_dir ? strlen(data_dir) : 0) + 1 /* \0 */;
-
-  wsp::string data_dir_str(data_dir_size); // for automatic cleanup on return
-  if (!data_dir_str()) return -ENOMEM;
-
-  int ret= snprintf(data_dir_str(), data_dir_size, "%s=%s",
-                    DATA_HOME_DIR_ENV, data_dir ? data_dir : "");
-
-  if (ret < 0 || ret >= data_dir_size)
-  {
-    WSREP_ERROR("sst_append_data_dir(): snprintf() failed: %d", ret);
-    return (ret < 0 ? ret : -EMSGSIZE);
-  }
-
-  env.append(data_dir_str());
+  env.append(env_str());
   return -env.error();
 }
 
@@ -1090,7 +1071,7 @@ static ssize_t sst_prepare_other (const char*  method,
     return -env.error();
   }
 
-  if ((ret= sst_append_auth_env(env, sst_auth)))
+  if ((ret= sst_append_env_var(env, WSREP_SST_AUTH_ENV, sst_auth)))
   {
     WSREP_ERROR("sst_prepare_other(): appending auth failed: %d", ret);
     return ret;
@@ -1098,7 +1079,7 @@ static ssize_t sst_prepare_other (const char*  method,
 
   if (data_home_dir)
   {
-    if ((ret= sst_append_data_dir(env, data_home_dir)))
+    if ((ret= sst_append_env_var(env, DATA_HOME_DIR_ENV, data_home_dir)))
     {
       WSREP_ERROR("sst_prepare_other(): appending data "
                   "directory failed: %d", ret);
@@ -1275,12 +1256,12 @@ ssize_t wsrep_sst_prepare (void** msg)
 
   *msg = malloc (msg_len);
   if (NULL != *msg) {
-    char* const method_ptr(reinterpret_cast<char*>(*msg));
+    char* const method_ptr(static_cast<char*>(*msg));
     strcpy (method_ptr, wsrep_sst_method);
     char* const addr_ptr(method_ptr + method_len + 1);
     strcpy (addr_ptr, addr_out);
 
-    WSREP_INFO ("Prepared SST request: %s|%s", method_ptr, addr_ptr);
+    WSREP_DEBUG("Prepared SST request: %s|%s", method_ptr, addr_ptr);
   }
   else {
     WSREP_ERROR("Failed to allocate SST request of size %zu. Can't continue.",
@@ -1733,6 +1714,7 @@ static int sst_donate_other (const char*   method,
                  "wsrep_sst_%s "
                  WSREP_SST_OPT_ROLE " 'donor' "
                  WSREP_SST_OPT_ADDR " '%s' "
+                 WSREP_SST_OPT_LPORT " '%u' "
                  WSREP_SST_OPT_SOCKET " '%s' "
                  WSREP_SST_OPT_DATA " '%s' "
                  "%s"
@@ -1740,7 +1722,8 @@ static int sst_donate_other (const char*   method,
                  WSREP_SST_OPT_GTID_DOMAIN_ID " '%d'"
                  "%s"
                  "%s",
-                 method, addr, mysqld_unix_port, mysql_real_data_home,
+                 method, addr, mysqld_port, mysqld_unix_port,
+                 mysql_real_data_home,
                  wsrep_defaults_file,
                  uuid, (long long) seqno, wsrep_gtid_domain_id,
                  binlog_opt_val,
@@ -1820,7 +1803,21 @@ wsrep_cb_status_t wsrep_sst_donate_cb (void* app_ctx, void* recv_ctx,
 
   const char* data   = method + method_len + 1;
 
-  if (check_request_str(data, address_char))
+  /* check for auth@addr separator */
+  const char* addr= strrchr(data, '@');
+  wsp::string remote_auth;
+  if (addr)
+  {
+    remote_auth.set(strndup(data, addr - data));
+    addr++;
+  }
+  else
+  {
+    // no auth part
+    addr= data;
+  }
+
+  if (check_request_str(addr, address_char))
   {
     WSREP_ERROR("Bad SST address string. SST canceled.");
     return WSREP_CB_FAILURE;
@@ -1841,15 +1838,25 @@ wsrep_cb_status_t wsrep_sst_donate_cb (void* app_ctx, void* recv_ctx,
   }
 
   int ret;
-  if ((ret= sst_append_auth_env(env, sst_auth_real)))
+  if ((ret= sst_append_env_var(env, WSREP_SST_AUTH_ENV, sst_auth_real)))
   {
     WSREP_ERROR("wsrep_sst_donate_cb(): appending auth env failed: %d", ret);
     return WSREP_CB_FAILURE;
   }
 
+  if (remote_auth())
+  {
+    if ((ret= sst_append_env_var(env, WSREP_SST_REMOTE_AUTH_ENV,remote_auth())))
+    {
+      WSREP_ERROR("wsrep_sst_donate_cb(): appending remote auth env failed: "
+                  "%d", ret);
+      return WSREP_CB_FAILURE;
+    }
+  }
+
   if (data_home_dir)
   {
-    if ((ret= sst_append_data_dir(env, data_home_dir)))
+    if ((ret= sst_append_env_var(env, DATA_HOME_DIR_ENV, data_home_dir)))
     {
       WSREP_ERROR("wsrep_sst_donate_cb(): appending data "
                   "directory failed: %d", ret);
@@ -1859,12 +1866,12 @@ wsrep_cb_status_t wsrep_sst_donate_cb (void* app_ctx, void* recv_ctx,
 
   if (!strcmp (WSREP_SST_MYSQLDUMP, method))
   {
-    ret = sst_donate_mysqldump(data, &current_gtid->uuid, uuid_str,
+    ret = sst_donate_mysqldump(addr, &current_gtid->uuid, uuid_str,
                                current_gtid->seqno, bypass, env());
   }
   else
   {
-    ret = sst_donate_other(method, data, uuid_str,
+    ret = sst_donate_other(method, addr, uuid_str,
                            current_gtid->seqno, bypass, env());
   }