Add mutt-filter mode

Only works for x-patch-sig style attestation, as doing DKIM attestation
requires that we unignore all headers, which just junks up the view.

Signed-off-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>

4 files changed, 38 insertions, 117 deletions

diff --git a/b4-send-email.sh b/b4-send-email.sh
deleted file mode 100755
index 9dd4640..0000000
--- a/b4-send-email.sh
+++ /dev/null
@@ -1,9 +0,0 @@
-#!/usr/bin/env bash
-#
-# Wrapper for running b4-send-email from checkout
-#
-
-REAL_SCRIPT=$(realpath -e ${BASH_SOURCE[0]})
-SCRIPT_TOP="${SCRIPT_TOP:-$(dirname ${REAL_SCRIPT})}"
-
-exec env PYTHONPATH="${SCRIPT_TOP}" python3 "${SCRIPT_TOP}/b4/attest.py" "${@}"
diff --git a/b4/__init__.py b/b4/__init__.py
index c1e0826..61f5cb1 100644
--- a/b4/__init__.py
+++ b/b4/__init__.py
@@ -570,7 +570,7 @@ class LoreSeries:
         if not failed:
             logger.info('  ---')
             for trailer, attmode in set(attdata):
-                logger.info('  %s %s', attmode, trailer)
+                logger.info('  %s Attestation-by: %s', attmode, trailer)
             return mbx
         elif not can_dkim_verify and config.get('attestation-check-dkim') == 'yes':
             logger.info('  ---')
@@ -1474,7 +1474,7 @@ class LoreAttestorDKIM(LoreAttestor):
         super().__init__(keyid)
 
     def get_trailer(self, fromaddr): # noqa
-        return 'Attestation-by: DKIM/%s (From: %s)' % (self.keyid, fromaddr)
+        return 'DKIM/%s (From: %s)' % (self.keyid, fromaddr)
 
 
 class LoreAttestorPGP(LoreAttestor):
@@ -1524,7 +1524,7 @@ class LoreAttestorPGP(LoreAttestor):
         else:
             uid = self.uids[0]
 
-        return 'Attestation-by: %s <%s> (pgp: %s)' % (uid[0], uid[1], self.keyid)
+        return '%s <%s> (pgp: %s)' % (uid[0], uid[1], self.keyid)
 
 
 class LoreAttestationSignature:
diff --git a/b4/attest.py b/b4/attest.py
index 1b464d0..5e3d384 100644
--- a/b4/attest.py
+++ b/b4/attest.py
@@ -9,11 +9,9 @@ import email
 import email.utils
 import email.message
 import email.header
-import smtplib
 import b4
 import argparse
 import base64
-import logging
 
 logger = b4.logger
 
@@ -92,72 +90,6 @@ def header_splitter(longstr: str, limit: int = 77) -> str:
     return ' '.join(splitstr)
 
 
-def attest_and_send(cmdargs: argparse.Namespace):
-    # Grab the message from stdin as bytes
-    if sys.stdin.isatty():
-        logger.critical('Pass the message to attest as stdin')
-        sys.exit(1)
-
-    inbytes = sys.stdin.buffer.read()
-    msg = email.message_from_bytes(inbytes)
-    lmsg = b4.LoreMessage(msg)
-    lmsg.load_hashes()
-    if not lmsg.attestation:
-        logger.debug('Nothing to attest in %s, sending as-is')
-        outbytes = inbytes
-    else:
-        in_header_attest(lmsg)
-        outbytes = lmsg.msg.as_bytes()
-
-    if cmdargs.nosend:
-        logger.info('--- MESSAGE FOLLOWS ---')
-        sys.stdout.buffer.write(outbytes)
-        return
-
-    if cmdargs.identity:
-        cfgname = f'sendemail\\.{cmdargs.identity}\\..*'
-    else:
-        cfgname = 'sendemail\\..*'
-
-    scfg = b4.get_config_from_git(cfgname)
-    sserver = scfg.get('smtpserver')
-    if not sserver:
-        logger.critical('MISSING: smtpserver option in %s', cfgname)
-        sys.exit(1)
-    if sserver[0] == '/':
-        args = [sserver, '-i'] + cmdargs.recipients
-        extraopts = scfg.get('smtpserveroption')
-        if extraopts:
-            args += extraopts.split()
-        ecode, out, err = b4._run_command(args, outbytes) # noqa
-        sys.stdout.buffer.write(out)
-        sys.stderr.buffer.write(err)
-        sys.exit(ecode)
-
-    sport = int(scfg.get('smtpserverport', '0'))
-    sdomain = scfg.get('smtpdomain')
-    suser = scfg.get('smtpuser')
-    spass = scfg.get('smtppass')
-    senc = scfg.get('smtpencryption', 'tls')
-    sfrom = scfg.get('from')
-    if not sfrom:
-        sfrom = lmsg.fromemail
-
-    logger.info('Connecting to %s', sserver)
-    if senc == 'ssl':
-        sconn = smtplib.SMTP_SSL(host=sserver, port=sport, local_hostname=sdomain)
-    else:
-        sconn = smtplib.SMTP(host=sserver, port=sport, local_hostname=sdomain)
-        if senc == 'tls':
-            sconn.starttls()
-    if suser:
-        logger.info('Logging in as user %s', suser)
-        sconn.login(suser, spass)
-
-    logger.info('Sending %s', lmsg.full_subject)
-    sconn.sendmail(sfrom, cmdargs.recipients, outbytes)
-
-
 def attest_patches(cmdargs: argparse.Namespace) -> None:
     for pf in cmdargs.patchfile:
         with open(pf, 'rb') as fh:
@@ -173,38 +105,28 @@ def attest_patches(cmdargs: argparse.Namespace) -> None:
             fh.write(lmsg.msg.as_bytes())
 
 
-if __name__ == '__main__':
-    # Special mode for running b4-send-email
-    # noinspection PyTypeChecker
-    parser = argparse.ArgumentParser(
-        prog='b4-send-email',
-        description='A drop-in wrapper for git-send-email to attest patches before sending',
-        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
-    )
-    parser.add_argument('-d', '--debug', action='store_true', default=False,
-                        help='Add more debugging info to the output')
-    parser.add_argument('-q', '--quiet', action='store_true', default=False,
-                        help='Output critical information only')
-    parser.add_argument('-i', dest='_compat', action='store_true', default=True,
-                        help='Sendmail compatibility thingamabob')
-    parser.add_argument('--identity', default='b4',
-                        help='The sendemail identity to use for real smtp/sendmail settings')
-    parser.add_argument('-n', '--no-send', dest='nosend', action='store_true', default=False,
-                        help='Do not send, just output what would be sent')
-    parser.add_argument('recipients', nargs='+', help='Message recipients')
-    _cmdargs = parser.parse_args()
-    logger.setLevel(logging.DEBUG)
-
-    ch = logging.StreamHandler()
-    formatter = logging.Formatter('b4: %(message)s')
-    ch.setFormatter(formatter)
-
-    if _cmdargs.quiet:
-        ch.setLevel(logging.CRITICAL)
-    elif _cmdargs.debug:
-        ch.setLevel(logging.DEBUG)
-    else:
-        ch.setLevel(logging.INFO)
-
-    logger.addHandler(ch)
-    attest_and_send(_cmdargs)
+def mutt_filter() -> None:
+    if sys.stdin.isatty():
+        logger.error('Error: Mutt mode expects a message on stdin')
+        sys.exit(1)
+    inb = sys.stdin.buffer.read()
+    try:
+        msg = email.message_from_bytes(inb)
+        if msg.get('x-patch-sig'):
+            lmsg = b4.LoreMessage(msg)
+            lmsg.load_hashes()
+            latt = lmsg.attestation
+            if latt and latt.validate(msg):
+                trailer = latt.lsig.attestor.get_trailer(lmsg.fromemail)
+                msg.add_header('Attested-By', trailer)
+                # Delete the x-patch-hashes and x-patch-sig headers so
+                # they don't boggle up the view
+                for i in reversed(range(len(msg._headers))):  # noqa
+                    hdrName = msg._headers[i][0].lower()  # noqa
+                    if hdrName in ('x-patch-hashes', 'x-patch-sig'):
+                        del msg._headers[i]  # noqa
+    except:  # noqa
+        # Don't prevent email from being displayed even if we died horribly
+        sys.stdout.buffer.write(inb)
+        return
+    sys.stdout.buffer.write(msg.as_bytes(policy=b4.emlpolicy))
diff --git a/b4/command.py b/b4/command.py
index 0393fea..ee865b9 100644
--- a/b4/command.py
+++ b/b4/command.py
@@ -42,7 +42,13 @@ def cmd_am(cmdargs):
 
 def cmd_attest(cmdargs):
     import b4.attest
-    b4.attest.attest_patches(cmdargs)
+    if cmdargs.mutt_filter:
+        b4.attest.mutt_filter()
+    elif len(cmdargs.patchfile):
+        b4.attest.attest_patches(cmdargs)
+    else:
+        logger.critical('ERROR: missing patches to attest')
+        sys.exit(1)
 
 
 def cmd_pr(cmdargs):
@@ -118,7 +124,9 @@ def cmd():
                         help='OBSOLETE: this option does nothing and will be removed')
     sp_att.add_argument('-o', '--output', default=None,
                         help='OBSOLETE: this option does nothing and will be removed')
-    sp_att.add_argument('patchfile', nargs='+', help='Patches to attest')
+    sp_att.add_argument('-m', '--mutt-filter', action='store_true', default=False,
+                        help='Run in mutt filter mode')
+    sp_att.add_argument('patchfile', nargs='*', help='Patches to attest')
     sp_att.set_defaults(func=cmd_attest)
 
     # b4 pr