gsm0408/gsm0408_test.c: introduce BCD number encoding / decoding test

So far, both gsm48_encode_bcd_number() and gsm48_decode_bcd_number2()
did not have any unit test coverage. Let's fill this gap by testing
the following scenarios:

  - encoding / decoding of a regular 9-digit MSISDN;
  - encoding / decoding of a MSISDN with optional LHV;
  - encoding / decoding of a long 15-digit MSISDN;
  - encoding / decoding of a MSISDN to a buffer:
    - with exactly matching size,
    - with lower size (truncation);
  - decoding LV buffer with incorrect length,
  - encoding / decoding an empty input buffer.

As it turns out, gsm48_decode_bcd_number2() does not properly
handle encoded LV if the output buffer size is equal to the
original MSISDN length + 1 (\0-terminator): one digit is lost.

For example, decoding of 15-digit long MSISDN to a buffer of size
16 (15 digits + 1 for \0) would give us only 14 digits. This is
reflected in the unit test output:

  Decoding HEX (buffer limit=16) '0821436587092143f5'...
    Expected: (rc=0) '123456789012345'
      Actual: (rc=0) '12345678901234'

Moreover, if the output buffer is shorter than decoded number,
gsm48_decode_bcd_number2() silently truncates it and returns 0,
while its description states, that the rc should reflect this.

To be fixed in the follow-up patches.

Change-Id: I4b2c330cf8ffe4427c0bee7d5f3b74be56ecd85d
Related: OS#4025

1 files changed, 48 insertions, 0 deletions

diff --git a/tests/gsm0408/gsm0408_test.ok b/tests/gsm0408/gsm0408_test.ok
index 0bd101de..2441b2b4 100644
--- a/tests/gsm0408/gsm0408_test.ok
+++ b/tests/gsm0408/gsm0408_test.ok
@@ -139,6 +139,54 @@ Decoding zero length Mobile Identities
     rc=1
     returned empty string
 
+BSD number encoding / decoding test
+- Running test: regular 9-digit MSISDN
+  - Encoding ASCII (buffer limit=0) '123456789'...
+    - Expected: (rc=6) '0521436587f9'
+    -   Actual: (rc=6) '0521436587f9'
+  - Decoding HEX (buffer limit=0) '0521436587f9'...
+    - Expected: (rc=0) '123456789'
+    -   Actual: (rc=0) '123456789'
+- Running test: regular 6-digit MSISDN with optional header (LHV)
+  - Encoding ASCII (buffer limit=0) '123456'...
+    - Expected: (rc=8) '0700000000214365'
+    -   Actual: (rc=8) '0721436587214365'
+  - Decoding HEX (buffer limit=0) '07deadbeef214365'...
+    - Expected: (rc=0) '123456'
+    -   Actual: (rc=0) '123456'
+- Running test: long 15-digit (maximum) MSISDN
+  - Encoding ASCII (buffer limit=0) '123456789012345'...
+    - Expected: (rc=9) '0821436587092143f5'
+    -   Actual: (rc=9) '0821436587092143f5'
+  - Decoding HEX (buffer limit=0) '0821436587092143f5'...
+    - Expected: (rc=0) '123456789012345'
+    -   Actual: (rc=0) '123456789012345'
+- Running test: long 15-digit (maximum) MSISDN, limited buffer
+  - Encoding ASCII (buffer limit=9) '123456789012345'...
+    - Expected: (rc=9) '0821436587092143f5'
+    -   Actual: (rc=9) '0821436587092143f5'
+  - Decoding HEX (buffer limit=16) '0821436587092143f5'...
+    - Expected: (rc=0) '123456789012345'
+    -   Actual: (rc=0) '12345678901234'
+- Running test: to be truncated 20-digit MSISDN
+  - Encoding ASCII (buffer limit=9) '12345678901234567890'...
+    - Expected: (rc=-5) ''
+    -   Actual: (rc=-5) ''
+  - Decoding HEX (buffer limit=16) '0a21436587092143658709'...
+    - Expected: (rc=0) '123456789012345'
+    -   Actual: (rc=0) '12345678901234'
+- Running test: LV incorrect length
+  - Decoding HEX (buffer limit=0) '05214365'...
+    - Expected: (rc=-5) '(none)'
+    -   Actual: (rc=-5) '(none)'
+- Running test: empty input buffer
+  - Encoding ASCII (buffer limit=0) ''...
+    - Expected: (rc=1) '00'
+    -   Actual: (rc=1) '00'
+  - Decoding HEX (buffer limit=0) ''...
+    - Expected: (rc=-5) '(none)'
+    -   Actual: (rc=-5) '(none)'
+
 Constructed RA:
 077-121-666-5
 MCC+MNC in BCD: 70 17 21