a (b`^@sdZddlmZmZmZmZddlZddlZddlm Z ddl Z ddl m mmmZddlmZmZmZmZmZmZmZmZmZmZmZmZmZmZm Z m!Z!m"Z"ddZ#dd d Z$d d Z%dddZ&ddZ'dS)a conda_content_trust.authentication This module contains functions that verify signatures and thereby authenticate data. Function Manifest for this Module verify_signature verify_gpg_signature verify_signable verify_root verify_delegation )absolute_importdivisionprint_functionunicode_literalsN) string_types)canonserialize PublicKey is_a_signablecheckformat_signableis_hex_signature is_hex_key is_signatureis_gpg_signatureis_a_signaturecheckformat_gpg_signaturecheckformat_hex_keycheckformat_byteslikecheckformat_delegationcheckformat_delegating_metadataSignatureErrorUnknownRoleErrorMetadataVerificationErrorc Cst|t||dddks0|dddkr8td|ddd}|d}|d}|ddd}|d}|d}|dd}|dd} |d | krtd t|d t| d t|||d dt|||d ddS)ui Given currently trusted root metadata, verify that new root metadata is trustworthy per the currently trusted root metadata. This requires a root chaining process as specified in The Update Framework specification. (Version N must be used in order to verify version N+1. Versions cannot be skipped.) # TODO✅: Proper docstring. signedtyperootzxExpected two instances of root metadata. Listed metadata type in one or both pieces of metadata provided is not "root". delegations thresholdpubkeysversionrzYRoot chaining failure: we currently trust a version of root that marks itself as version zG, and the provided new root metadata to verify marks itself as version z; the new version must be 1 more than the old version: root updates MUST be processed one at a time for security reasons: no root version may be skipped.TgpgN)r ValueErrorrstrverify_signable) Ztrusted_current_root_metadataZuntrusted_new_root_metadataZroot_expectationsZexpected_thresholdauthorized_pub_keysZnew_root_expectationsZnew_expected_thresholdZnew_authorized_pub_keysZtrusted_root_versionZuntrusted_root_versionr&Alib/python3.9/site-packages/conda_content_trust/authentication.py verify_root>sT     r(FcCst|tstdtt||dvr.tdt|t|z t|Wn Yn20||ddkrtd|d|ddd|dd }||vrtd |d ||d }||d }t ||||ddS)a Verify that the given untrusted, delegated-to metadata is trustworthy, based on the given trusted metadata's expectations (expected keys and threshold). This function returns if verification succeeds. In other words, check trusted_delegating_metadata's delegation to delegation_name to find the expected signing keys and threshold for delegation_name, and then check untrusted_delegated_metadata to see if it is signed by enough of the right keys to be trustworthy. For example, using root metadata to verify key_mgr metadata looks like this: verify_delegation( 'key_mgr', , ) Arguments: (string) delegation_name is the name of the role delegated. (dict) trusted_delegating_metadata is a signable JSON-serializable object representing the full metadata that delegates to role delegation_name. (dict) untrusted_delegated_metadata is a signable JSON-serializable object (bool) gpg should be true if the signatures to be verified in the delegated metadata are expected to be OpenPGP signatures rather than the usual raw ed25519 signatures. Exceptions: - raises UnknownRoleError if there's no matching delegation - raises SignatureError if a signature is bad or signatures don't match expectations (threshold, wrong keys, etc.) # TODO: Consider exception handling to raise MetadataVerificationError instead? - raises MetadataVerificationError if the metadata type is unexpected - raises TypeError or ValueError if the arguments are invalid z(delegation_name must be a string, not a )TFz!Argument "gpg" must be a boolean.rrzrz#verify_signable..z2authorized_pub_keys must be a list of hex strings rz%threshold must be a positive integer.rZ signatureszYIgnoring signature from "key" with public key value that does not look like a key value: zDIgnoring "signature" that does not look like a hex signature value: zDIgnoring "signature" that does not look like a gpg signature value: z Ignoring signature from a key ("z0") that is not authorized to sign this metadata.zKIgnoring "signature" that does not look like a raw ed25519 signature value.r1z'Expected good signatures from at least z unique keys from a set of z keys. Saw z signatures, only zJ of which were good signatures over the given data from the expected keys.N)r r*r)listallintritemsr printr#rrr from_hexr4 cryptography exceptionsZInvalidSignatureverify_gpg_signaturelenr) Zsignabler%rr!Z signed_dataZgood_sigs_from_trusted_keysZ pubkey_hexr1Zpublicr&r&r'r$@s-                 r$cCst|t|t|t|}t|d}tjj j tjj j tjj }|||||d|tdt||}|t|d|dS)u? Verifies a raw ed25519 signature that happens to have been produced by an OpenPGP signing process (RFC4880). NOTE that this code DISREGARDS most OpenPGP semantics: is interested solely in the verification of a signature over the given data, with the raw ed25519 public key given (in the form of a hex string). This code does not care about the GPG public key infrastructure, including key self-revocation, expiry, or the relationship of any key with any other key through OpenPGP (subkeys, key-to-key signoff, etc.). This codebase uses OpenPGP signatures solely as a means of facilitating a TUF-style public key infrastructure, where the public key values are trusted with specific privileges directly. ⚠️💣 ABSOLUTELY DO NOT use this for general purpose verification of GPG signatures!! It is for our root signatures only, where OpenPGP signing is just a proxy for a simple ed25519 signature through a hardware signing mechanism. # TODO: ✅ Proper docstring modeled on verify_signature. Z other_headerssz>Ir1N)rrrr r>r/r0r?hazmat primitivesZhashesZHashZSHA256ZbackendsZdefault_backendupdatestructpackrBfinalizer.)r1 key_valuer3r2Zadditional_header_dataZhasherZdigestr&r&r'rAs$       rA)F)F)(__doc__Z __future__rrrrr/rFZsixrZcryptography.exceptionsr?Z1cryptography.hazmat.primitives.asymmetric.ed25519rCrDZ asymmetricr,commonrr r r r r rrrrrrrrrrrr(r+r4r$rAr&r&r&r's Lk m- .