certbot.crypto_util module¶
Certbot client crypto utility functions.
-
certbot.crypto_util.
init_save_key
(key_size, key_dir, keyname='key-certbot.pem')[source]¶ Initializes and saves a privkey.
Inits key and saves it in PEM format on the filesystem.
Note
keyname is the attempted filename, it may be different if a file already exists at the path.
- Parameters
key_size (int) – RSA key size in bits
key_dir (str) – Key save directory.
keyname (str) – Filename of key
- Returns
Key
- Return type
- Raises
ValueError – If unable to generate the key given key_size.
-
certbot.crypto_util.
init_save_csr
(privkey, names, path)[source]¶ Initialize a CSR with the given private key.
- Parameters
privkey (
certbot.util.Key
) – Key to include in the CSRnames (set) –
str
names to include in the CSRpath (str) – Certificate save directory.
- Returns
CSR
- Return type
-
certbot.crypto_util.
valid_csr
(csr)[source]¶ Validate CSR.
Check if
csr
is a valid CSR for the given domains.- Parameters
csr (str) – CSR in PEM.
- Returns
Validity of CSR.
- Return type
bool
-
certbot.crypto_util.
csr_matches_pubkey
(csr, privkey)[source]¶ Does private key correspond to the subject public key in the CSR?
- Parameters
csr (str) – CSR in PEM.
privkey (str) – Private key file contents (PEM)
- Returns
Correspondence of private key to CSR subject public key.
- Return type
bool
-
certbot.crypto_util.
import_csr_file
(csrfile, data)[source]¶ Import a CSR file, which can be either PEM or DER.
- Parameters
csrfile (str) – CSR filename
data (str) – contents of the CSR file
- Returns
(
crypto.FILETYPE_PEM
, util.CSR object representing the CSR, list of domains requested in the CSR)- Return type
tuple
-
certbot.crypto_util.
make_key
(bits)[source]¶ Generate PEM encoded RSA key.
- Parameters
bits (int) – Number of bits, at least 1024.
- Returns
new RSA key in PEM form with specified number of bits
- Return type
str
-
certbot.crypto_util.
valid_privkey
(privkey)[source]¶ Is valid RSA private key?
- Parameters
privkey (str) – Private key file contents in PEM
- Returns
Validity of private key.
- Return type
bool
-
certbot.crypto_util.
verify_renewable_cert
(renewable_cert)[source]¶ For checking that your certs were not corrupted on disk.
- Several things are checked:
Signature verification for the cert.
That fullchain matches cert and chain when concatenated.
Check that the private key matches the certificate.
- Parameters
renewable_cert (certbot.interfaces.RenewableCert) – cert to verify
- Raises
errors.Error – If verification fails.
-
certbot.crypto_util.
verify_renewable_cert_sig
(renewable_cert)[source]¶ Verifies the signature of a RenewableCert object.
- Parameters
renewable_cert (certbot.interfaces.RenewableCert) – cert to verify
- Raises
errors.Error – If signature verification fails.
-
certbot.crypto_util.
verify_signed_payload
(public_key, signature, payload, signature_hash_algorithm)[source]¶ Check the signature of a payload.
- Parameters
public_key (RSAPublicKey/EllipticCurvePublicKey) – the public_key to check signature
signature (bytes) – the signature bytes
payload (bytes) – the payload bytes
- :param cryptography.hazmat.primitives.hashes.HashAlgorithm
signature_hash_algorithm: algorithm used to hash the payload
- Raises
InvalidSignature – If signature verification fails.
errors.Error – If public key type is not supported
-
certbot.crypto_util.
verify_cert_matches_priv_key
(cert_path, key_path)[source]¶ Verifies that the private key and cert match.
- Parameters
cert_path (str) – path to a cert in PEM format
key_path (str) – path to a private key file
- Raises
errors.Error – If they don’t match.
-
certbot.crypto_util.
verify_fullchain
(renewable_cert)[source]¶ Verifies that fullchain is indeed cert concatenated with chain.
- Parameters
renewable_cert (certbot.interfaces.RenewableCert) – cert to verify
- Raises
errors.Error – If cert and chain do not combine to fullchain.
-
certbot.crypto_util.
get_sans_from_cert
(cert, typ=1)[source]¶ Get a list of Subject Alternative Names from a certificate.
- Parameters
cert (str) – Certificate (encoded).
typ –
crypto.FILETYPE_PEM
orcrypto.FILETYPE_ASN1
- Returns
A list of Subject Alternative Names.
- Return type
list
-
certbot.crypto_util.
get_names_from_cert
(csr, typ=1)[source]¶ Get a list of domains from a cert, including the CN if it is set.
- Parameters
cert (str) – Certificate (encoded).
typ –
crypto.FILETYPE_PEM
orcrypto.FILETYPE_ASN1
- Returns
A list of domain names.
- Return type
list
-
certbot.crypto_util.
dump_pyopenssl_chain
(chain, filetype=1)[source]¶ Dump certificate chain into a bundle.
- Parameters
chain (list) – List of
crypto.X509
(or wrapped injosepy.util.ComparableX509
).
-
certbot.crypto_util.
notBefore
(cert_path)[source]¶ When does the cert at cert_path start being valid?
- Parameters
cert_path (str) – path to a cert in PEM format
- Returns
the notBefore value from the cert at cert_path
- Return type
datetime.datetime
-
certbot.crypto_util.
notAfter
(cert_path)[source]¶ When does the cert at cert_path stop being valid?
- Parameters
cert_path (str) – path to a cert in PEM format
- Returns
the notAfter value from the cert at cert_path
- Return type
datetime.datetime
-
certbot.crypto_util.
sha256sum
(filename)[source]¶ Compute a sha256sum of a file.
NB: In given file, platform specific newlines characters will be converted into their equivalent unicode counterparts before calculating the hash.
- Parameters
filename (str) – path to the file whose hash will be computed
- Returns
sha256 digest of the file in hexadecimal
- Return type
str
-
certbot.crypto_util.
cert_and_chain_from_fullchain
(fullchain_pem)[source]¶ Split fullchain_pem into cert_pem and chain_pem
- Parameters
fullchain_pem (str) – concatenated cert + chain
- Returns
tuple of string cert_pem and chain_pem
- Return type
tuple
- Raises
errors.Error – If there are less than 2 certificates in the chain.