js/mailhops.js: completely rework AH parsing.

Since the AH can comprise multiple lines, parse each line individually
until we found all data.

The parsing is complicated, but naïve field splitting leads to incorrect
results.

Generally, scan up to the next "dkim=" part, extract the state (which is
the value) and then look for the reason, which might or might not be
parenthesis-enclosed or start with a "reason=" key or both.

All other data up to the next "dkim=" part or end of the line or
semicolon will be treated as extrainfo and shown if the preference has
been enabled.

We handle "spf=" parts in about the same way.

js/mailhops.js

@@ -299,6 +299,53 @@ class MailHops {
     browser.messageDisplayAction.setTitle({ title: this.message.sender.title, tabId: this.tabId });
   }
 
+  extractMaybeQuotedValue(line, key) {
+    let ret = [ ];
+    let new_line = line;
+
+    console.assert (key.length);
+
+    // The possible combinations we might be interested in.
+    let dQuote = new RegExp (key + '="(.*?)"');
+    let sQuote = new RegExp (key + "='(.*?)'");
+    let nQuote = new RegExp (key + '=(.*?)(?:\\s|$)');
+
+    let match = line.match (dQuote);
+    if (null !== match) {
+      ret.push (match[1]);
+    }
+
+    if (!ret.length) {
+      match = line.match (sQuote);
+      if (null !== match) {
+        ret.push (match[1]);
+      }
+    }
+
+    if (!ret.length) {
+      match = line.match (nQuote);
+      if (null !== match) {
+        ret.push (match[1]);
+      }
+    }
+
+    if (ret.length) {
+      // Match length must be non-zero.
+      console.assert (match[0].length);
+
+      // Drop data leading up to the match.
+      new_line = new_line.substring (match.index);
+
+      // Drop the match itself.
+      new_line = new_line.substring (match[0].length);
+
+      // Add to return value.
+      ret.push (new_line);
+    }
+
+    return ret;
+  }
+
   sanitizeString(str) {
     return str.replace (/\t/g, ' ').replace (/\s+/g, ' ').replace (/</g, '&lt;').replace (/>/g, '&gt;').trim ();
   }
@@ -342,39 +389,192 @@ class MailHops {
     //Authentication-Results
     //http://tools.ietf.org/html/rfc8601
     if (header_auth) {
-      var headerAuthArr = header_auth.split(';');
+      this.LOG ('Authentication-Results header found, parsing...\n');
-      var dkim_result;
+      var headerAuthArr = [];
-      var spf_result;
+
-      for (var h = 0; h < headerAuthArr.length; h++) {
+      // The header might contain multiple lines, so iterate above them.
-        if (headerAuthArr[h].indexOf('dkim=') != -1) {
+      var headerAuthArr_ = header_auth.split('\n');
-          dkim_result = headerAuthArr[h];
+      var dkimState = '';
-          if (header_spf)
+      var spfState = '';
-            break;
+      var dkimReason = '';
+      var spfReason = '';
+      var dkimAux = '';
+      var spfAux = '';
+      var gotDkimState = false;
+      var gotSpfState = false;
+      for (var i = 0; i < headerAuthArr_.length; ++i) {
+        var curLine = headerAuthArr_[i];
+        this.LOG ('current header line: ' + curLine + '\n');
+
+        // This is the actual fun part.
+        // The AH can very funky and naïve field splitting often leads to
+        // wrong results.
+        // We'll heave to tread carefully and parse data in a more
+        // sophisticated way, relying on arcane knowledge.
+        //
+        // It might be temping to try to merge the dkim and spf sections below,
+        // but doing so is not really possible, since the formats are
+        // different.
+        let statePos = 0;
+        let stateWork = curLine;
+        while ((!gotDkimState) &&
+               (-1 !== (statePos = stateWork.indexOf ('dkim=')))) {
+          // Fetch "dkim=" value, potentially quoted.
+          // While the RFC doesn't mention anything about quote-enclosing
+          // values, it probably doesn't hurt to support it.
+          let extract = this.extractMaybeQuotedValue (stateWork, 'dkim');
+
+          if (extract.length) {
+            dkimState = extract[0];
+            stateWork = extract[1];
+            gotDkimState = true;
+            this.LOG ("extracted DKIM state: " + dkimState + "; continuing with new line: " + stateWork);
+          }
+          else {
+            // Nothing found on this line, continue.
+            this.LOG ("nothing found on current line (leftover) '" + truncatedWork + "', continuing...");
+            continue;
+          }
+
+          // Look ahead to find the next "dkim=" section. This will mark the
+          // end of our current chunk (if it exists).
+          let stateEnd = -1;
+          let truncatedWork = stateWork;
+          if (-1 !== (stateEnd = stateWork.indexOf ('dkim=', 5))) {
+            truncatedWork = truncatedWork.substring (0, stateEnd);
+          }
+
+          // Now fetch additional data.
+          // Typically, that should be "reason=".
+          extract = this.extractMaybeQuotedValue (truncatedWork, 'reason');
+
+          if (extract.length) {
+            dkimReason = extract[0];
+            truncatedWork = extract[1];
+            this.LOG ("extracted DKIM reason: " + dkimReason + "; continuing with new line: " + truncatedWork);
+          }
+
+          // Same MTA append a string such as "(1024-bit key; unprotected)",
+          // add this to the reason.
+          const key_data = new RegExp ('\\(\\d+-bit key(?:; .+?)?\\)');
+          let match = truncatedWork.match (key_data);
+          if (null !== match) {
+            if (dkimReason.length) {
+              dkimReason += ' ';
+            }
+            dkimReason += match[0];
+            truncatedWork = truncatedWork.substring (match.index);
+            truncatedWork = truncatedWork.substring (match[0].length);
+          }
+
+          // Others enclose the reason in parentheses.
+          const paren_reason = new RegExp ('\\(.+?\\)');
+          match = truncatedWork.match (paren_reason);
+          if (null !== match) {
+            if (dkimReason.length) {
+              dkimReason += ' ';
+            }
+            dkimReason += match[0];
+            truncatedWork = truncatedWork.substring (match.index);
+            truncatedWork = truncatedWork.substring (match[0].length);
+          }
+
+          // Everything else should be additional data, up until the first
+          // semicolon or end of the line.
+          const aux_data = new RegExp ('(.+?)(?:;|$)');
+          match = truncatedWork.match (aux_data);
+          if (null !== match) {
+            dkimAux = match[1];
+          }
         }
-        if (!header_spf && headerAuthArr[h].indexOf('spf=') != -1) {
+
-          spf_result = headerAuthArr[h];
+        // Do the same for SPF data.
-          if (dkim_result)
+        statePos = 0;
-            break;
+        stateWork = curLine;
+        while ((!gotSpfState) &&
+               (-1 !== (statePos = stateWork.indexOf ('spf=')))) {
+          // Refer to the DKIM section above for more information.
+          let extract = this.extractMaybeQuotedValue (stateWork, 'spf');
+
+          if (extract.length) {
+            spfState = extract[0];
+            stateWork = extract[1];
+            gotSpfState = true;
+          }
+          else {
+            // Nothing found on this line, continue.
+            this.LOG ("nothing found on current line (leftover) '" + stateWork + "', continuing...");
+            continue;
+          }
+
+          let stateEnd = -1;
+          let truncatedWork = stateWork;
+          if (-1 !== (stateEnd = stateWork.indexOf ('spf=', 4))) {
+            truncatedWork = truncatedWork.substring (0, stateEnd);
+          }
+
+          // Now fetch additional data.
+          // Reason is usually enclosed in parentheses.
+          const paren_reason = new RegExp ('\\(.+?\\)');
+          let match = truncatedWork.match (paren_reason);
+          if (null !== match) {
+            spfReason = match[0];
+            truncatedWork = truncatedWork.substring (match.index);
+            truncatedWork = truncatedWork.substring (match[0].length);
+          }
+
+          // Everything else is additional data.
+          const aux_data = new RegExp ('(.+?)[;|$]');
+          match = truncatedWork.match (aux_data);
+          if (null !== match) {
+            spfAux = match[1];
+          }
         }
       }
-      if (dkim_result) {
+
-        dkim_result = dkim_result.replace(/^\s+/, "");
+      if (gotDkimState) {
-        var dkimArr = dkim_result.split(' ');
+        // Just sanitize our data.
+        dkimState = this.sanitizeString (dkimState);
+        dkimReason = this.sanitizeString (dkimReason);
+        dkimAux = this.sanitizeString (dkimAux);
+
+        var copy = dkimState;
+        if (dkimReason.length) {
+          copy += ' - ' + dkimReason;
+        }
+        if ((this.options.extrainfo) && (dkimAux.length)) {
+          copy += '\n<br />' + dkimAux;
+        }
+        copy += '\n<br />\n<br />' + MailHopsUtils.dkim(dkimState).trim();
+
+        this.LOG ("DKIM state and data: " + copy);
         auth.push({
           type: 'DKIM',
           color: 'green',
-          icon: '/images/auth/' + dkimArr[0].replace('dkim=', '') + '.png',
+          icon: '/images/auth/' + dkimState.toLowerCase () + '.png',
-          copy: dkim_result + '\n' + MailHopsUtils.dkim(dkimArr[0].replace('dkim=', '')).trim()
+          copy: copy
         });
       }
-      if (spf_result) {
+      if (gotSpfState) {
-        spf_result = spf_result.replace(/^\s+/, "");
+        spfState = this.sanitizeString (spfState);
-        var spfArr = spf_result.split(' ');
+        spfReason = this.sanitizeString (spfReason);
+        spfAux = this.sanitizeString (spfAux);
+
+        var copy = spfState;
+        if (spfReason.length) {
+          copy += ' ' + spfReason;
+        }
+        if ((this.options.extrainfo) && (spfAux.length)) {
+          copy += '\n<br />' + spfAux;
+        }
+        copy += '\n<br />\n<br />' + MailHopsUtils.spf(spfState).trim();
+
+        this.LOG ("SPF state and data: " + copy);
         auth.push({
           type: 'SPF',
           color: 'green',
-          icon: '/images/auth/' + spfArr[0].replace('spf=', '') + '.png',
+          icon: '/images/auth/' + spfState.toLowerCase () + '.png',
-          copy: spf_result + '\n' + MailHopsUtils.spf(spfArr[0].replace('spf=', '')).trim()
+          copy: copy
         });
       }
     }