X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;f=daklib%2Futils.py;h=230391a192a2e046b1ead07b38a722182270a279;hb=5ea129bba83114905c1266b77744eeed8e9bb020;hp=a32b0c468d023f74e48d841e92c8f18b897a2178;hpb=7df9c3b974bcd1c3bc40d29d154f6b86b6454ddd;p=dak.git diff --git a/daklib/utils.py b/daklib/utils.py index a32b0c46..230391a1 100644 --- a/daklib/utils.py +++ b/daklib/utils.py @@ -865,10 +865,80 @@ def gpgv_get_status_output(cmd, status_read, status_write): return output, status, exit_status -############################################################ +################################################################################ +def process_gpgv_output(status): + # Process the status-fd output + keywords = {} + internal_error = "" + for line in status.split('\n'): + line = line.strip() + if line == "": + continue + split = line.split() + if len(split) < 2: + internal_error += "gpgv status line is malformed (< 2 atoms) ['%s'].\n" % (line) + continue + (gnupg, keyword) = split[:2] + if gnupg != "[GNUPG:]": + internal_error += "gpgv status line is malformed (incorrect prefix '%s').\n" % (gnupg) + continue + args = split[2:] + if keywords.has_key(keyword) and (keyword != "NODATA" and keyword != "SIGEXPIRED"): + internal_error += "found duplicate status token ('%s').\n" % (keyword) + continue + else: + keywords[keyword] = args + + return (keywords, internal_error) + +################################################################################ + +def retrieve_key (filename, keyserver=None, keyring=None): + """Retrieve the key that signed 'filename' from 'keyserver' and +add it to 'keyring'. Returns nothing on success, or an error message +on error.""" + + # Defaults for keyserver and keyring + if not keyserver: + keyserver = Cnf["Dinstall::KeyServer"] + if not keyring: + keyring = Cnf["Dinstall::GPGKeyring"] + + # Ensure the filename contains no shell meta-characters or other badness + if not re_taint_free.match(filename): + return "%s: tainted filename" % (filename) + + # Invoke gpgv on the file + status_read, status_write = os.pipe(); + cmd = "gpgv --status-fd %s --keyring /dev/null %s" % (status_write, filename) + (_, status, _) = gpgv_get_status_output(cmd, status_read, status_write) -def check_signature (sig_filename, reject, data_filename="", keyrings=None): + # Process the status-fd output + (keywords, internal_error) = process_gpgv_output(status) + if internal_error: + return internal_error + + if not keywords.has_key("NO_PUBKEY"): + return "didn't find expected NO_PUBKEY in gpgv status-fd output" + + fingerprint = keywords["NO_PUBKEY"][0] + # XXX - gpg sucks. You can't use --secret-keyring=/dev/null as + # it'll try to create a lockfile in /dev. A better solution might + # be a tempfile or something. + cmd = "gpg --no-default-keyring --secret-keyring=%s --no-options" \ + % (Cnf["Dinstall::SigningKeyring"]) + cmd += " --keyring %s --keyserver %s --recv-key %s" \ + % (keyring, keyserver, fingerprint) + (result, output) = commands.getstatusoutput(cmd) + if (result != 0): + return "'%s' failed with exit code %s" % (cmd, result) + + return "" + +################################################################################ + +def check_signature (sig_filename, reject, data_filename="", keyrings=None, autofetch=None): """Check the signature of a file and return the fingerprint if the signature is valid or 'None' if it's not. The first argument is the filename whose signature should be checked. The second argument is a @@ -878,8 +948,9 @@ the second is an optional prefix string. It's possible for reject() to be called more than once during an invocation of check_signature(). The third argument is optional and is the name of the files the detached signature applies to. The fourth argument is optional and is -a *list* of keyrings to use. -""" +a *list* of keyrings to use. 'autofetch' can either be None, True or +False. If None, the default behaviour specified in the config will be +used.""" # Ensure the filename contains no shell meta-characters or other badness if not re_taint_free.match(sig_filename): @@ -893,6 +964,15 @@ a *list* of keyrings to use. if not keyrings: keyrings = (Cnf["Dinstall::PGPKeyring"], Cnf["Dinstall::GPGKeyring"]) + # Autofetch the signing key if that's enabled + if autofetch == None: + autofetch = Cnf.get("Dinstall::KeyAutoFetch") + if autofetch: + error_msg = retrieve_key(sig_filename) + if error_msg: + reject(error_msg) + return None + # Build the command line status_read, status_write = os.pipe(); cmd = "gpgv --status-fd %s" % (status_write) @@ -903,26 +983,7 @@ a *list* of keyrings to use. (output, status, exit_status) = gpgv_get_status_output(cmd, status_read, status_write) # Process the status-fd output - keywords = {} - bad = internal_error = "" - for line in status.split('\n'): - line = line.strip() - if line == "": - continue - split = line.split() - if len(split) < 2: - internal_error += "gpgv status line is malformed (< 2 atoms) ['%s'].\n" % (line) - continue - (gnupg, keyword) = split[:2] - if gnupg != "[GNUPG:]": - internal_error += "gpgv status line is malformed (incorrect prefix '%s').\n" % (gnupg) - continue - args = split[2:] - if keywords.has_key(keyword) and (keyword != "NODATA" and keyword != "SIGEXPIRED"): - internal_error += "found duplicate status token ('%s').\n" % (keyword) - continue - else: - keywords[keyword] = args + (keywords, internal_error) = process_gpgv_output(status) # If we failed to parse the status-fd output, let's just whine and bail now if internal_error: @@ -931,6 +992,7 @@ a *list* of keyrings to use. reject("Please report the above errors to the Archive maintainers by replying to this mail.", "") return None + bad = "" # Now check for obviously bad things in the processed output if keywords.has_key("SIGEXPIRED"): reject("The key used to sign %s has expired." % (sig_filename))