runtests: support dynamicly base64 encoded sections in tests

This allows us to make test cases to use base64 at run-time and still
use and verify information determined at run-time, such as the IMAP test
server's port number in test 842.

This change makes 12 tests run again that basically never ran since we
moved to dynamic port numbers.

ftpserver.pl is adjusted to load test instructions and test number from
the preprocessed test file.

FILEFORMAT.md now documents the new base64 encoding syntax.

Reported-by: Marcel Raad
Fixes #5761
Closes #5775

15 files changed, 77 insertions, 91 deletions

diff --git a/tests/FILEFORMAT.md b/tests/FILEFORMAT.md
index 0f5ae7f51..6f6e71bb7 100644
--- a/tests/FILEFORMAT.md
+++ b/tests/FILEFORMAT.md
@@ -21,6 +21,25 @@ variables are substituted by the their respective contents and the output
 version of the test file is stored as `log/testNUM`. That version is what will
 be read and used by the test servers.
 
+## Base64 Encoding
+
+In the preprocess stage, a special instruction can be used to have runtests.pl
+base64 encode a certain section and insert in the generated output file. This
+is in particular good for test cases where the test tool is expected to pass
+in base64 encoded content that might use dynamic information that is unique
+for this particular test invocation, like the server port number.
+
+To insert a base64 encoded string into the output, use this syntax:
+
+    %b64[ data to encode ]b64%
+
+The data to encode can then use any of the existing variables mentioned below,
+or even percent-encoded individual bytes. As an example, insert the HTTP
+server's port number (in ASCII) followed by a space and the hexadecimal byte
+9a:
+
+    %b64[%HTTPPORT %9a]b64%
+
 # Variables
 
 When the test is preprocessed, a range of "variables" in the test file will be
diff --git a/tests/data/test842 b/tests/data/test842
index 1d9181e17..2b5ae1c18 100644
--- a/tests/data/test842
+++ b/tests/data/test842
@@ -15,7 +15,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTHENTICATE +
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== A002 OK AUTHENTICATE completed
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% A002 OK AUTHENTICATE completed
 </servercmd>
 <data>
 From: me@somewhere

@@ -42,9 +42,6 @@ IMAP OAuth 2.0 (OAUTHBEARER) authentication
 </command>
 # The protocol section doesn't support ways of specifying the raw data in the
 # base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%IMAPPORT' ne '9003' );"
-</precheck>
 </client>
 
 #
@@ -53,7 +50,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 A001 CAPABILITY

 A002 AUTHENTICATE OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 A003 SELECT 842

 A004 FETCH 1 BODY[]

 A005 LOGOUT

diff --git a/tests/data/test843 b/tests/data/test843
index bd39dd907..131188933 100644
--- a/tests/data/test843
+++ b/tests/data/test843
@@ -41,11 +41,6 @@ IMAP OAuth 2.0 (OAUTHBEARER) authentication with initial response
  <command>
 'imap://%HOSTIP:%IMAPPORT/843/;MAILINDEX=1' -u user --oauth2-bearer mF_9.B5f-4.1JqM
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%IMAPPORT' ne '9003' );"
-</precheck>
 </client>
 
 #
@@ -53,7 +48,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <verify>
 <protocol>
 A001 CAPABILITY

-A002 AUTHENTICATE OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+A002 AUTHENTICATE OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 A003 SELECT 843

 A004 FETCH 1 BODY[]

 A005 LOGOUT

diff --git a/tests/data/test844 b/tests/data/test844
index c5093d2b8..8573bc2fd 100644
--- a/tests/data/test844
+++ b/tests/data/test844
@@ -15,9 +15,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTHENTICATE +
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== +
-eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxlX3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9uIn0=
-REPLY AQ== A002 NO Authentication failed
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% A002 NO Authentication failed
 </servercmd>
 </reply>
 
@@ -33,11 +31,6 @@ IMAP OAuth 2.0 (OAUTHBEARER) failure as continuation
  <command>
 'imap://%HOSTIP:%IMAPPORT/844/;MAILINDEX=1' -u user --oauth2-bearer mF_9.B5f-4.1JqM
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%IMAPPORT' ne '9003' );"
-</precheck>
 </client>
 
 #
@@ -53,8 +46,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 A001 CAPABILITY

 A002 AUTHENTICATE OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

-AQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 </protocol>
 </verify>
 </testcase>
diff --git a/tests/data/test845 b/tests/data/test845
index 70562c7ab..449eef353 100644
--- a/tests/data/test845
+++ b/tests/data/test845
@@ -33,11 +33,6 @@ IMAP OAuth 2.0 (OAUTHBEARER) failure as continuation with initial response
  <command>
 'imap://%HOSTIP:%IMAPPORT/845/;MAILINDEX=1' -u user --oauth2-bearer mF_9.B5f-4.1JqM
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%IMAPPORT' ne '9003' );"
-</precheck>
 </client>
 
 #
@@ -52,8 +47,8 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 # transfer and such a connection will not get a "LOGOUT"
 <protocol>
 A001 CAPABILITY

-A002 AUTHENTICATE OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMwFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

-AQ==

+A002 AUTHENTICATE OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%IMAPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

+%b64[%01]b64%

 </protocol>
 </verify>
 </testcase>
diff --git a/tests/data/test887 b/tests/data/test887
index 35419b502..ccf364955 100644
--- a/tests/data/test887
+++ b/tests/data/test887
@@ -17,7 +17,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTH +
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== +OK Login successful
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% +OK Login successful
 </servercmd>
 <data>
 From: me@somewhere

@@ -42,11 +42,6 @@ POP3 OAuth 2.0 (OAUTHBEARER) authentication
  <command>
 pop3://%HOSTIP:%POP3PORT/887 -u user --oauth2-bearer mF_9.B5f-4.1JqM
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%POP3PORT' ne '9001' );"
-</precheck>
 </client>
 
 #
@@ -55,7 +50,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 CAPA

 AUTH OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 RETR 887

 QUIT

 </protocol>
diff --git a/tests/data/test888 b/tests/data/test888
index 78463feaa..465a2d0ce 100644
--- a/tests/data/test888
+++ b/tests/data/test888
@@ -42,11 +42,6 @@ POP3 OAuth 2.0 (OAUTHBEARER) authentication with initial response
  <command>
 pop3://%HOSTIP:%POP3PORT/888 -u user --oauth2-bearer mF_9.B5f-4.1JqM --sasl-ir
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%POP3PORT' ne '9001' );"
-</precheck>
 </client>
 
 #
@@ -54,7 +49,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <verify>
 <protocol>
 CAPA

-AUTH OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+AUTH OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 RETR 888

 QUIT

 </protocol>
diff --git a/tests/data/test889 b/tests/data/test889
index 2edb371e9..9658d386c 100644
--- a/tests/data/test889
+++ b/tests/data/test889
@@ -17,7 +17,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTH +
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxlX3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9uIn0
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxlX3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9uIn0
 REPLY AQ== -ERR Authentication failed
 </servercmd>
 </reply>
@@ -34,11 +34,6 @@ POP3 OAuth 2.0 (OAUTHBEARER) failure as continuation
  <command>
 pop3://%HOSTIP:%POP3PORT/889 -u user --oauth2-bearer mF_9.B5f-4.1JqM
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%POP3PORT' ne '9001' );"
-</precheck>
 </client>
 
 #
@@ -54,7 +49,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 CAPA

 AUTH OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 AQ==

 </protocol>
 </verify>
diff --git a/tests/data/test890 b/tests/data/test890
index ca0ccc7b5..4d6701ab0 100644
--- a/tests/data/test890
+++ b/tests/data/test890
@@ -34,11 +34,6 @@ POP3 OAuth 2.0 (OAUTHBEARER) failure as continuation with initial response
  <command>
 pop3://%HOSTIP:%POP3PORT/890 -u user --oauth2-bearer mF_9.B5f-4.1JqM --sasl-ir
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%POP3PORT' ne '9001' );"
-</precheck>
 </client>
 
 #
@@ -53,7 +48,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 # transfer and such a connection will not get a "QUIT"
 <protocol>
 CAPA

-AUTH OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwMQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+AUTH OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%POP3PORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 AQ==

 </protocol>
 </verify>
diff --git a/tests/data/test946 b/tests/data/test946
index c6753dc1e..aa88364fa 100644
--- a/tests/data/test946
+++ b/tests/data/test946
@@ -16,7 +16,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTH 334 OAUTHBEARER supported
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== 235 Authenticated
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% 235 Authenticated
 </servercmd>
 </reply>
 
@@ -35,11 +35,6 @@ mail body
  <command>
 smtp://%HOSTIP:%SMTPPORT/946 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user --oauth2-bearer mF_9.B5f-4.1JqM -T -
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%SMTPPORT' ne '9005' );"
-</precheck>
 </client>
 
 #
@@ -48,7 +43,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 EHLO 946

 AUTH OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 MAIL FROM:<sender@example.com>

 RCPT TO:<recipient@example.com>

 DATA

diff --git a/tests/data/test947 b/tests/data/test947
index 03c3fbe37..d2622be8d 100644
--- a/tests/data/test947
+++ b/tests/data/test947
@@ -35,11 +35,6 @@ mail body
  <command>
 smtp://%HOSTIP:%SMTPPORT/947 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user --oauth2-bearer mF_9.B5f-4.1JqM --sasl-ir -T -
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%SMTPPORT' ne '9005' );"
-</precheck>
 </client>
 
 #
@@ -47,7 +42,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <verify>
 <protocol>
 EHLO 947

-AUTH OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+AUTH OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 MAIL FROM:<sender@example.com>

 RCPT TO:<recipient@example.com>

 DATA

diff --git a/tests/data/test948 b/tests/data/test948
index 8385f0cd2..a6eadf5fa 100644
--- a/tests/data/test948
+++ b/tests/data/test948
@@ -16,7 +16,7 @@ RFC7628
 <servercmd>
 AUTH OAUTHBEARER
 REPLY AUTH 334 OAUTHBEARER supported
-REPLY bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ== 334 eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxlX3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9uIn0
+REPLY %b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% 334 eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxlX3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9uIn0
 REPLY AQ== 535 Username and Password not accepted. Learn more at\r\n535 http://support.example.com/mail/oauth
 </servercmd>
 </reply>
@@ -36,11 +36,6 @@ mail body
  <command>
 smtp://%HOSTIP:%SMTPPORT/948 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user --oauth2-bearer mF_9.B5f-4.1JqM -T -
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%SMTPPORT' ne '9005' );"
-</precheck>
 </client>
 
 #
@@ -56,7 +51,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 <protocol>
 EHLO 948

 AUTH OAUTHBEARER

-bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+%b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 AQ==

 </protocol>
 </verify>
diff --git a/tests/data/test949 b/tests/data/test949
index 345940077..82064f19a 100644
--- a/tests/data/test949
+++ b/tests/data/test949
@@ -36,11 +36,6 @@ mail body
  <command>
 smtp://%HOSTIP:%SMTPPORT/949 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user --oauth2-bearer mF_9.B5f-4.1JqM --sasl-ir -T -
 </command>
-# The protocol section doesn't support ways of specifying the raw data in the
-# base64 encoded message so we must assert this
-<precheck>
-perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP' ne '127.0.0.1' || '%SMTPPORT' ne '9005' );"
-</precheck>
 </client>
 
 #
@@ -55,7 +50,7 @@ perl -e "print 'Test requires default test server host and port' if ( '%HOSTIP'
 # transfer and such a connection will not get a "QUIT"
 <protocol>
 EHLO 949

-AUTH OAUTHBEARER bixhPXVzZXIsAWhvc3Q9MTI3LjAuMC4xAXBvcnQ9OTAwNQFhdXRoPUJlYXJlciBtRl85LkI1Zi00LjFKcU0BAQ==

+AUTH OAUTHBEARER %b64[n,a=user,%01host=127.0.0.1%01port=%SMTPPORT%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64%

 AQ==

 </protocol>
 </verify>
diff --git a/tests/ftpserver.pl b/tests/ftpserver.pl
index a0b36e5de..d587f453e 100755
--- a/tests/ftpserver.pl
+++ b/tests/ftpserver.pl
@@ -83,6 +83,7 @@ my $proto = 'ftp';  # default server protocol
 my $srcdir;         # directory where ftpserver.pl is located
 my $srvrname;       # server name for presentation purposes
 my $cwd_testno;     # test case numbers extracted from CWD command
+my $testno = 0;     # test case number (read from ftpserver.cmd)
 my $path   = '.';
 my $logdir = $path .'/log';
 
@@ -449,17 +450,14 @@ sub startsf {
 # Returns the given test's reply data
 #
 sub getreplydata {
-    my ($testno) = @_;
+    my ($num) = @_;
     my $testpart = "";
 
-    $testno =~ s/^([^0-9]*)//;
-    if($testno > 10000) {
-       $testpart = $testno % 10000;
-       $testno = int($testno / 10000);
+    $num =~ s/^([^0-9]*)//;
+    if($num > 10000) {
+       $testpart = $num % 10000;
     }
 
-    loadtest("$srcdir/data/test$testno");
-
     my @data = getpart("reply", "data$testpart");
     if((!@data) && ($testpart ne "")) {
         @data = getpart("reply", "data");
@@ -2093,7 +2091,8 @@ my @ftpdir=("total 20\r\n",
     logmsg "pass LIST data on data connection\n";
 
     if($cwd_testno) {
-        loadtest("$srcdir/data/test$cwd_testno");
+        loadtest("$logdir/test$cwd_testno") ||
+            loadtest("$srcdir/data/test$cwd_testno");
 
         my @data = getpart("reply", "data");
         for(@data) {
@@ -2156,7 +2155,8 @@ sub MDTM_ftp {
         $testno = int($testno / 10000);
     }
 
-    loadtest("$srcdir/data/test$testno");
+    loadtest("$logdir/test$testno") ||
+        loadtest("$srcdir/data/test$testno");
 
     my @data = getpart("reply", "mdtm");
 
@@ -2209,7 +2209,8 @@ sub SIZE_ftp {
         $testno = int($testno / 10000);
     }
 
-    loadtest("$srcdir/data/test$testno");
+    loadtest("$logdir/test$testno") ||
+        loadtest("$srcdir/data/test$testno");
 
     my @data = getpart("reply", "size");
 
@@ -2298,7 +2299,8 @@ sub RETR_ftp {
         $testno = int($testno / 10000);
     }
 
-    loadtest("$srcdir/data/test$testno");
+    loadtest("$logdir/test$testno") ||
+        loadtest("$srcdir/data/test$testno");
 
     my @data = getpart("reply", "data$testpart");
 
@@ -2881,6 +2883,10 @@ sub customize {
             $nosave = 1;
             logmsg "FTPD: NOSAVE prevents saving of uploaded data\n";
         }
+        elsif($_ =~ /^Testnum (\d+)/){
+            $testno = $1;
+            logmsg "FTPD: run test case number: $testno\n";
+        }
     }
     close(CUSTOM);
 }
@@ -3069,6 +3075,8 @@ while(1) {
     $| = 1;
 
     &customize(); # read test control instructions
+    loadtest("$logdir/test$testno") ||
+        loadtest("$srcdir/data/test$testno");
 
     my $welcome = $commandreply{"welcome"};
     if(!$welcome) {
diff --git a/tests/runtests.pl b/tests/runtests.pl
index cc70a1011..b25b3f456 100755
--- a/tests/runtests.pl
+++ b/tests/runtests.pl
@@ -76,6 +76,7 @@ use strict;
 use warnings;
 use Cwd;
 use Digest::MD5 qw(md5);
+use MIME::Base64;
 
 # Subs imported from serverhelp module
 use serverhelp qw(
@@ -3338,6 +3339,20 @@ sub subVariables {
     $$thing =~ s/${prefix}H2CVER/$h2cver/g;
 }
 
+sub subBase64 {
+    my ($thing) = @_;
+
+    # cut out the base64 piece
+    if($$thing =~ s/%b64\[(.*)\]b64%/%%B64%%/i) {
+        my $d = $1;
+        # encode %NN characters
+        $d =~ s/%([0-9A-Fa-f]{2})/chr(hex($1))/eg;
+        my $enc = encode_base64($d, "");
+        # put the result into there
+        $$thing =~ s/%%B64%%/$enc/;
+    }
+}
+
 sub fixarray {
     my @in = @_;
 
@@ -3560,16 +3575,21 @@ sub singletest {
     for my $s (@entiretest) {
         my $f = $s;
         subVariables(\$s, "%");
+        subBase64(\$s);
         if($f ne $s) {
             $diff++;
         }
         print D $s;
     }
     close(D);
+
     # remove the separate test file again if nothing was updated to keep
     # things simpler
     unlink($otest) if(!$diff);
 
+    # in case the process changed the file, reload it
+    loadtest("log/test${testnum}") if($diff);
+
     # timestamp required servers verification end
     $timesrvrend{$testnum} = Time::HiRes::time();