Add missing NULL check when analyzing AssuredCtrl messages with no parameters (#44)

* SMF plugin crashes when there are no parameters in an assured control
message.

Check for a null pointer return from p_get_proto_data in
smf_analysis_assuredctrl

* Correct comment in README regarding where to install plugin.
%APPDATA% now includes 'Roaming' in the variable already.  Also
try using '-1' as a plugin-version on windows developer loads.

* Update the Windows and Global Plugin Folder doc to be more clear.

* Remove 'Roaming' frmo workflow docs as that is already in %APPDATA%

Author: RagnarPaulson

.github/workflows/build_plugin.yml

@@ -46,7 +46,7 @@ jobs:
       PATCH_VERSION: ${{ inputs.PATCH_VERSION || '0' }}
       # this goes into FILEVERSION which appears when you hover over the DLL, but cannot 
       # contain a string like "dev"
-      SMF_PLUGIN_PATCH_VERSION: ${{ inputs.SMF_PLUGIN_PATCH_VERSION || '0' }}
+      SMF_PLUGIN_PATCH_VERSION: ${{ inputs.SMF_PLUGIN_PATCH_VERSION || '-1' }}
   build_linux:
     uses: ./.github/workflows/ubuntu.yml
     with:

.github/workflows/docs/wireshark_smf_4-6-x_instructions.md

@@ -9,7 +9,7 @@
 ### Windows Plugin Folder
 Personal Plugin Folder:
 
-`%APPDATA%\Roaming\Wireshark\plugins\4.6\epan`
+`%APPDATA%\Wireshark\plugins\4.6\epan`
 
 Global Plugin Folder:
 

README.md

@@ -16,13 +16,13 @@ This project is a plugin for wireshark that will dissect Solace SMF protocol.
 3. Unzip the folder and place the .dll (Windows) or .so (Mac/Linux) file in the Wireshark plugin folder, under `epan`. The plugin folder path varies for each OS.
 
 ### Windows Plugin Folder
-Personal Plugin Folder:
+Personal Plugin Folder (version specific, use the wireshark major.minor):
 
-`%APPDATA%\Roaming\Wireshark\plugins\4.0\epan`
+`%APPDATA%\Wireshark\plugins\4.6\epan`
 
-Global Plugin Folder:
+Global Plugin Folder (version specific, use the wireshark major.minor):
 
-`C:\Program Files\Wireshark\plugins\4.0\plugins\epan`
+`C:\Program Files\Wireshark\plugins\4.6\plugins\epan`
 
 ### macOS/Linux Plugin Folder
 Personal Plugin Folder:

src/smf/smf-analysis.c

@@ -737,6 +737,10 @@ void smf_analysis_assuredctrl_param(tvbuff_t *tvb, packet_info* pinfo, uint8_t p
 void smf_analysis_assuredctrl(tvbuff_t *tvb, packet_info* pinfo, proto_tree* tree) {
     smf_analysis_assuredctrl_buf_t *smf_analysis_assuredctrl_buf_p = (smf_analysis_assuredctrl_buf_t *)p_get_proto_data(wmem_file_scope(), pinfo,
             getAssuredCtrlProto(), (uint32_t)tvb_raw_offset(tvb));
+    if (NULL == smf_analysis_assuredctrl_buf_p) {
+        // no more buffer to analyze, there were no parameters in the assuredctrl message. Just return
+        return;
+    }
     if (smf_analysis_assuredctrl_buf_p->numTransportMsg_m != 0 || smf_analysis_assuredctrl_buf_p->numAckedMsg_m != 0) {
         proto_item *item = proto_tree_add_item(tree, hf_assuredctrl_smf_analysis, tvb, 0, 0, ENC_NA);
         proto_item_set_generated(item);