pop3: Added support for SASL based authentication mechanism detection

Added support for detecting the supported SASL authentication mechanisms
via the AUTH command. There are two ways of detecting them, either by
using the AUTH command, that will return -ERR if not supported or by
using the CAPA command which will return SASL and the list of mechanisms
if supported, not include SASL if SASL authentication is not supported
or -ERR if the CAPA command is not supported. As such it seems simpler
to use the AUTH command and fallback to normal clear text authentication
if the the command is not supported.

Additionally updated the test cases to return -ERR when the AUTH command
is encountered. Additional test cases will be added when support for the
individual authentication mechanisms is added.

7 files changed, 16 insertions, 0 deletions

diff --git a/tests/data/test808 b/tests/data/test808
index 756801c6b..57e1382b1 100644
--- a/tests/data/test808
+++ b/tests/data/test808
@@ -10,6 +10,7 @@ LIST
 # Server-side
 <reply>
 <servercmd>
+REPLY AUTH -ERR unsupported command

 REPLY LIST +OK 808 100
 </servercmd>
 </reply>
@@ -32,6 +33,7 @@ pop3://%HOSTIP:%POP3PORT/808 -l -u user:secret
 # Verify data after the test has been "shot"
 <verify>
 <protocol>
+AUTH

 USER user

 PASS secret

 LIST 808

diff --git a/tests/data/test809 b/tests/data/test809
index e9f22dd83..7cd04c891 100644
--- a/tests/data/test809
+++ b/tests/data/test809
@@ -11,6 +11,7 @@ FAILURE
 # Server-side
 <reply>
 <servercmd>
+REPLY AUTH -ERR unsupported command

 REPLY LIST -ERR no such message
 </servercmd>
 </reply>
@@ -36,6 +37,7 @@ pop3://%HOSTIP:%POP3PORT/809 -l -u user:secret
 56
 </errorcode>
 <protocol>
+AUTH

 USER user

 PASS secret

 LIST 809

diff --git a/tests/data/test810 b/tests/data/test810
index 09f9562a3..2e24c295b 100644
--- a/tests/data/test810
+++ b/tests/data/test810
@@ -13,6 +13,7 @@ LIST
 # packets
 <servercmd>
 SLOWDOWN
+REPLY AUTH -ERR unsupported command

 </servercmd>
 # When doing LIST, we get the default list output hard-coded in the test
 # POP3 server
@@ -41,6 +42,7 @@ pop3://%HOSTIP:%POP3PORT/ -u user:secret
 # Verify data after the test has been "shot"
 <verify>
 <protocol>
+AUTH

 USER user

 PASS secret

 LIST

diff --git a/tests/data/test811 b/tests/data/test811
index ca107abcc..06fa57dcb 100644
--- a/tests/data/test811
+++ b/tests/data/test811
@@ -10,6 +10,7 @@ LIST
 # Server-side
 <reply>
 <servercmd>
+REPLY AUTH -ERR unsupported command

 REPLY LIST +OK but no messages\r\n.
 </servercmd>
 <datacheck>
@@ -34,6 +35,7 @@ pop3://%HOSTIP:%POP3PORT/ -u user:secret
 # Verify data after the test has been "shot"
 <verify>
 <protocol>
+AUTH

 USER user

 PASS secret

 LIST

diff --git a/tests/data/test812 b/tests/data/test812
index eb2a83669..9f1ba9296 100644
--- a/tests/data/test812
+++ b/tests/data/test812
@@ -11,6 +11,7 @@ FAILURE
 # Server-side
 <reply>
 <servercmd>
+REPLY AUTH -ERR unsupported command

 REPLY RETR -ERR no such message
 </servercmd>
 </reply>
@@ -36,6 +37,7 @@ pop3://%HOSTIP:%POP3PORT/812 -u user:secret
 56
 </errorcode>
 <protocol>
+AUTH

 USER user

 PASS secret

 RETR 812

diff --git a/tests/data/test813 b/tests/data/test813
index 4953af413..13cfd7074 100644
--- a/tests/data/test813
+++ b/tests/data/test813
@@ -10,6 +10,7 @@ FAILURE
 # Server-side
 <reply>
 <servercmd>
+REPLY AUTH -ERR unsupported command

 REPLY PASS -ERR invalid login
 </servercmd>
 </reply>
@@ -35,6 +36,7 @@ pop3://%HOSTIP:%POP3PORT/813 -u user:wrong
 67
 </errorcode>
 <protocol>
+AUTH

 USER user

 PASS wrong

 QUIT

diff --git a/tests/data/test815 b/tests/data/test815
index df7b1b6dd..9779fe690 100644
--- a/tests/data/test815
+++ b/tests/data/test815
@@ -9,6 +9,9 @@ RETR
 #
 # Server-side
 <reply>
+<servercmd>

+REPLY AUTH -ERR unsupported command

+</servercmd>

 <data>
 From: me@somewhere

 To: fake@nowhere

@@ -49,6 +52,7 @@ pop3://%HOSTIP:%POP3PORT/815 -u user:secret
 # Verify data after the test has been "shot"
 <verify>
 <protocol>
+AUTH

 USER user

 PASS secret

 RETR 815