bitbake: fetch2/wget: fetch securely by default

The days of broken certificates are behind us now, so instead of always
passing --no-check-certificate to wget, don't pass it by default and
instead only pass it BB_CHECK_SSL_CERTS = "0".

[ YOCTO #14108 ]

(Bitbake rev: 4104850dd36096a9ff01836c5fca9ac0e452bcf8)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/wget.py

@@ -52,13 +52,19 @@ class WgetProgressHandler(bb.progress.LineFilterProgressHandler):
 
 
 class Wget(FetchMethod):
+    """Class to fetch urls via 'wget'"""
 
     # CDNs like CloudFlare may do a 'browser integrity test' which can fail
     # with the standard wget/urllib User-Agent, so pretend to be a modern
     # browser.
     user_agent = "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:84.0) Gecko/20100101 Firefox/84.0"
 
-    """Class to fetch urls via 'wget'"""
+    def check_certs(self, d):
+        """
+        Should certificates be checked?
+        """
+        return (d.getVar("BB_CHECK_SSL_CERTS") or "1") != "0"
+
     def supports(self, ud, d):
         """
         Check to see if a given url can be fetched with wget.
@@ -82,7 +88,10 @@ class Wget(FetchMethod):
         if not ud.localfile:
             ud.localfile = d.expand(urllib.parse.unquote(ud.host + ud.path).replace("/", "."))
 
-        self.basecmd = d.getVar("FETCHCMD_wget") or "/usr/bin/env wget -t 2 -T 30 --passive-ftp --no-check-certificate"
+        self.basecmd = d.getVar("FETCHCMD_wget") or "/usr/bin/env wget -t 2 -T 30 --passive-ftp"
+
+        if not self.check_certs(d):
+            self.basecmd += " --no-check-certificate"
 
     def _runwget(self, ud, d, command, quiet, workdir=None):
 
@@ -309,7 +318,11 @@ class Wget(FetchMethod):
         with bb.utils.environment(**newenv):
             import ssl
 
-            context = ssl._create_unverified_context()
+            if self.check_certs(d):
+                context = ssl.create_default_context()
+            else:
+                context = ssl._create_unverified_context()
+
             handlers = [FixedHTTPRedirectHandler,
                         HTTPMethodFallback,
                         urllib.request.ProxyHandler(),