Just my two cents.
As pointed out in other responses, now to sign ios app (compatible with ios and ipados 15) with codesign command on MacOS prior to Big Sur add the --generate-entitlement-der flag. I can sign my app with Xcode 10.3 using this python 2.7 (tried both on MacOS Mojave 10.14 and MacOS Catalina 10.15) snippet code:
from fabric.api import local
local('cp %s "%s"' % ("/path/to/embedded.mobileprovision", app_full_path))
local('xattr -rc %s' % app_full_path)
local("codesign -f --generate-entitlement-der -vv -s \"%s\" --entitlements \"%s/Entitlements.plist\" %s" % (
env.code_sign_identity, app_full_path, app_full_path)
)
Output example log:
[localhost] local: cp /path/to/embedded.mobileprovision "/path/to/Payload/appname.app"
[localhost] local: xattr -rc /path/to/Payload/appname.app
[localhost] local: codesign -f --generate-entitlement-der -vv -s "iPhone Distribution: XXX S.p.A." --entitlements "/path/to/Payload/appname.app/Entitlements.plist" /path/to/Payload/appname.app
/path/to/Payload/appname.app: replacing existing signature
/path/to/Payload/appname.app: signed app bundle with Mach-O universal (armv7 arm64) [com.name.reverse.dns]
Some additional tips...
MacOS keychain should contains the Apple certificate used to create the mobile provisioning profile, which is also utilized to distribute the app we’re signing. You can check it using the command security find-identity -p codesigning:
$ security find-identity -p codesigning
Policy: Code Signing
Matching identities
1) AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA "iPhone Distribution: XXX S.p.A."
...
13) CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC "iPhone Developer: Name Surname (DDDDDDDDDD)"
13 identities found
Valid identities only
1) AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA "iPhone Distribution: XXX S.p.A."
...
13) CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC "iPhone Developer: Name Surname (DDDDDDDDDD)"
13 identities found
After the ipa zip archive creation, you can use the Gem ipa_analyzer (https://github.com/bitrise-io/ipa_analyzer) to verify if the app is correctly signed:
$ zip -9 -y -r /path/to/appname.ipa /path/to/Payload
$ gem install ipa_analyzer --user-install
$ PATHAPP="/path/to/appname.ipa"
$ ~/.gem/ruby/2.6.0/bin/ipa_analyzer -i ${PATHAPP} -p --info-plist --prov | grep -E "ExpirationDate|CFBundleIdentifier|DER-Encoded-Profile"
"DER-Encoded-Profile": "#<StringIO:0x00000f0000000008>",
"ExpirationDate": "2022-09-18T12:15:25+00:00",
"CFBundleIdentifier": "com.name.reverse.dns",
As additional references about this issue, you can read also this Apple documentation page and this Apple forum post.