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public_key(3erl) | Erlang Module Definition | public_key(3erl) |
NAME¶
public_key - API module for public-key infrastructure.DESCRIPTION¶
Provides functions to handle public-key infrastructure, for details see public_key(7).DATA TYPES¶
Note:
All records used in this Reference Manual are generated from ASN.1
specifications and are documented in the User's Guide. See Public-key
Records.
Use the following include directive to get access to the records and constant
macros described here and in the User's Guide:
-include_lib("public_key/include/public_key.hrl").The following data types are used in the functions for public_key:
- oid():
- Object identifier, a tuple of integers as generated by the ASN.1 compiler.
- boolean() =:
- true | false
- string() =:
- [bytes()]
- der_encoded() =:
- binary()
- pki_asn1_type() =:
- 'Certificate'
| 'RSAPrivateKey'
| 'RSAPublicKey'
| 'DSAPrivateKey'
| 'DSAPublicKey'
| 'DHParameter'
| 'SubjectPublicKeyInfo'
| 'PrivateKeyInfo'
| 'CertificationRequest'
| 'CertificateList'
| 'ECPrivateKey'
| 'EcpkParameters'
- pem_entry () =:
- {pki_asn1_type(), binary(), %% DER or encrypted DER
not_encrypted | cipher_info()}
- cipher_info() = :
- {"RC2-CBC" | "DES-CBC" | "DES-EDE3-CBC", crypto:strong_rand_bytes(8)
| {#'PBEParameter{}, digest_type()} | #'PBES2-params'{}}
- public_key() =:
- rsa_public_key() | dsa_public_key() | ec_public_key()
- private_key() =:
- rsa_private_key() | dsa_private_key() | ec_private_key()
- rsa_public_key() =:
- #'RSAPublicKey'{}
- rsa_private_key() =:
- #'RSAPrivateKey'{}
- dsa_public_key() =:
- {integer(), #'Dss-Parms'{}}
- dsa_private_key() =:
- #'DSAPrivateKey'{}
- ec_public_key():
- = {#'ECPoint'{}, #'ECParameters'{} | {namedCurve, oid()}}
- ec_private_key() =:
- #'ECPrivateKey'{}
- public_crypt_options() =:
- [{rsa_pad, rsa_padding()}]
- rsa_padding() =:
- 'rsa_pkcs1_padding'
| 'rsa_pkcs1_oaep_padding'
| 'rsa_no_padding'
- digest_type() = :
- Union of rsa_digest_type(), dss_digest_type(), and ecdsa_digest_type().
- rsa_digest_type() = :
- 'md5' | 'sha' | 'sha224' | 'sha256' | 'sha384' | 'sha512'
- dss_digest_type() = :
- 'sha'
- ecdsa_digest_type() = :
- 'sha'| 'sha224' | 'sha256' | 'sha384' | 'sha512'
- crl_reason() = :
- unspecified
| keyCompromise
| cACompromise
| affiliationChanged
| superseded
| cessationOfOperation
| certificateHold
| privilegeWithdrawn
| aACompromise
- issuer_name() =:
- {rdnSequence,[#'AttributeTypeAndValue'{}]}
- ssh_file() =:
- openssh_public_key
| rfc4716_public_key
| known_hosts
| auth_keys
EXPORTS¶
compute_key(OthersKey, MyKey)->
Types:
OthersKey = #'ECPoint'{} | binary(), MyKey =
#'ECPrivateKey'{} | binary()
Params = #'DHParameter'{}
Computes shared secret.
decrypt_private(CipherText, Key) -> binary()
Types:
CipherText = binary()
Key = rsa_private_key()
Options = public_crypt_options()
Public-key decryption using the private key. See also
crypto:private_decrypt/4
decrypt_public(CipherText, Key) - > binary()
Types:
CipherText = binary()
Key = rsa_public_key()
Options = public_crypt_options()
Public-key decryption using the public key. See also
crypto:public_decrypt/4
der_decode(Asn1type, Der) -> term()
Types:
Asn1Type = atom()
ASN.1 type present in the Public Key applications ASN.1
specifications.
Der = der_encoded()
Decodes a public-key ASN.1 DER encoded entity.
der_encode(Asn1Type, Entity) -> der_encoded()
Types:
Asn1Type = atom()
ASN.1 type present in the Public Key applications ASN.1
specifications.
Entity = term()
Erlang representation of Asn1Type
Encodes a public-key entity with ASN.1 DER encoding.
dh_gex_group(MinSize, SuggestedSize, MaxSize, Groups) -> {ok,
{Size,Group}} | {error,Error}
Types:
MinSize = positive_integer()
SuggestedSize = positive_integer()
MaxSize = positive_integer()
Groups = undefined | [{Size,[{G,P}]}]
Size = positive_integer()
Group = {G,P}
G = positive_integer()
P = positive_integer()
Selects a group for Diffie-Hellman key exchange with the key size in the range
MinSize...MaxSize and as close to SuggestedSize as possible. If
Groups == undefined a default set will be used, otherwise the group is
selected from Groups.
First a size, as close as possible to SuggestedSize, is selected. Then one group
with that key size is randomly selected from the specified set of groups. If
no size within the limits of MinSize and MaxSize is available,
{error,no_group_found} is returned.
The default set of groups is listed in lib/public_key/priv/moduli. This
file may be regenerated like this:
encrypt_private(PlainText, Key) -> binary()
$> cd $ERL_TOP/lib/public_key/priv/ $> generate ---- wait until all background jobs has finished. It may take several days ! $> cat moduli-* > moduli $> cd ..; make
Types:
PlainText = binary()
Key = rsa_private_key()
Public-key encryption using the private key. See also
crypto:private_encrypt/4.
encrypt_public(PlainText, Key) -> binary()
Types:
PlainText = binary()
Key = rsa_public_key()
Public-key encryption using the public key. See also
crypto:public_encrypt/4.
generate_key(Params) -> {Public::binary(), Private::binary()} |
#'ECPrivateKey'{}
Types:
Params = #'DHParameter'{} | {namedCurve, oid()} |
#'ECParameters'{}
Generates a new keypair.
pem_decode(PemBin) -> [pem_entry()]
Types:
PemBin = binary()
Example {ok, PemBin} =
file:read_file("cert.pem").
Decodes PEM binary data and returns entries as ASN.1 DER encoded entities.
pem_encode(PemEntries) -> binary()
Types:
PemEntries = [pem_entry()]
PemEntries = [pem_entry()]
Creates a PEM binary.
pem_entry_decode(PemEntry) -> term()
Types:
PemEntry = pem_entry()
Password = string()
Decodes a PEM entry. pem_decode/1 returns a list of PEM entries. Notice
that if the PEM entry is of type 'SubjectPublickeyInfo', it is further decoded
to an rsa_public_key() or dsa_public_key().
pem_entry_encode(Asn1Type, Entity) -> pem_entry()
Types:
Asn1Type = pki_asn1_type()
Entity = term()
Password = string()
Erlang representation of Asn1Type. If
Asn1Type is 'SubjectPublicKeyInfo', Entity must be either an
rsa_public_key(), dsa_public_key() or an ec_public_key()
and this function creates the appropriate 'SubjectPublicKeyInfo' entry.
CipherInfo = cipher_info()
Creates a PEM entry that can be feed to pem_encode/1.
pkix_decode_cert(Cert, otp|plain) -> #'Certificate'{} |
#'OTPCertificate'{}
Types:
Cert = der_encoded()
Decodes an ASN.1 DER-encoded PKIX certificate. Option otp uses the
customized ASN.1 specification OTP-PKIX.asn1 for decoding and also recursively
decode most of the standard parts.
pkix_encode(Asn1Type, Entity, otp | plain) -> der_encoded()
Types:
Asn1Type = atom()
The ASN.1 type can be 'Certificate', 'OTPCertificate' or
a subtype of either.
Entity = #'Certificate'{} | #'OTPCertificate'{} | a valid subtype
DER encodes a PKIX x509 certificate or part of such a certificate. This function
must be used for encoding certificates or parts of certificates that are
decoded/created in the otp format, whereas for the plain format this
function directly calls der_encode/2.
pkix_is_issuer(Cert, IssuerCert) -> boolean()
Types:
Cert = der_encoded() | #'OTPCertificate'{} |
#'CertificateList'{}
IssuerCert = der_encoded() | #'OTPCertificate'{}
Checks if IssuerCert issued Cert.
pkix_is_fixed_dh_cert(Cert) -> boolean()
Types:
Cert = der_encoded() | #'OTPCertificate'{}
Checks if a certificate is a fixed Diffie-Hellman certificate.
pkix_is_self_signed(Cert) -> boolean()
Types:
Cert = der_encoded() | #'OTPCertificate'{}
Checks if a certificate is self-signed.
pkix_issuer_id(Cert, IssuedBy) -> {ok, IssuerID} | {error, Reason}
Types:
Cert = der_encoded() | #'OTPCertificate'{}
IssuedBy = self | other
IssuerID = {integer(), issuer_name()}
The issuer id consists of the serial number and the
issuers name.
Reason = term()
Returns the issuer id.
pkix_normalize_name(Issuer) -> Normalized
Types:
Issuer = issuer_name()
Normalized = issuer_name()
Normalizes an issuer name so that it can be easily compared to another issuer
name.
pkix_path_validation(TrustedCert, CertChain, Options) -> {ok,
{PublicKeyInfo, PolicyTree}} | {error, {bad_cert, Reason}}
Types:
TrustedCert = #'OTPCertificate'{} | der_encoded() |
atom()
PublicKeyInfo = {?'rsaEncryption' | ?'id-dsa', rsa_public_key() | integer(),
'NULL' | 'Dss-Parms'{}}
PolicyTree = term()
Normally a trusted certificate, but it can also be a
path-validation error that can be discovered while constructing the input to
this function and that is to be run through the verify_fun. Examples
are unknown_ca and selfsigned_peer.
CertChain = [der_encoded()]
A list of DER-encoded certificates in trust order ending
with the peer certificate.
Options = proplists:proplist()
At the moment this is always an empty list as policies
are not currently supported.
Reason = cert_expired | invalid_issuer | invalid_signature | name_not_permitted
| missing_basic_constraint | invalid_key_usage | {revoked, crl_reason()} |
atom()
Performs a basic path validation according to RFC 5280. However, CRL validation
is done separately by pkix_crls_validate/3 and is to be called from
the supplied verify_fun.
Available options:
Possible reasons for a bad certificate:
pkix_crl_issuer(CRL) -> issuer_name()
- {verify_fun, fun()}:
- The fun must be defined as:
fun(OtpCert :: #'OTPCertificate'{}, Event :: {bad_cert, Reason :: atom() | {revoked, atom()}} | {extension, #'Extension'{}}, InitialUserState :: term()) -> {valid, UserState :: term()} | {valid_peer, UserState :: term()} | {fail, Reason :: term()} | {unknown, UserState :: term()}.
If the verify callback fun returns {fail, Reason}, the verification
process is immediately stopped. If the verify callback fun returns {valid,
UserState}, the verification process is continued. This can be used to
accept specific path validation errors, such as selfsigned_peer, as
well as verifying application-specific extensions. If called with an extension
unknown to the user application, the return value {unknown, UserState}
is to be used.
- {max_path_length, integer()}:
-
The max_path_length is the maximum number of non-self-issued intermediate certificates that can follow the peer certificate in a valid certification path. So, if max_path_length is 0, the PEER must be signed by the trusted ROOT-CA directly, if it is 1, the path can be PEER, CA, ROOT-CA, if it is 2, the path can be PEER, CA, CA, ROOT-CA, and so on.
- cert_expired:
- Certificate is no longer valid as its expiration date has passed.
- invalid_issuer:
- Certificate issuer name does not match the name of the issuer certificate in the chain.
- invalid_signature:
- Certificate was not signed by its issuer certificate in the chain.
- name_not_permitted:
- Invalid Subject Alternative Name extension.
- missing_basic_constraint:
- Certificate, required to have the basic constraints extension, does not have a basic constraints extension.
- invalid_key_usage:
- Certificate key is used in an invalid way according to the key-usage extension.
- {revoked, crl_reason()}:
- Certificate has been revoked.
- atom():
- Application-specific error reason that is to be checked by the verify_fun.
Types:
CRL = der_encoded() | #'CertificateList'{}
Returns the issuer of the CRL.
pkix_crls_validate(OTPCertificate, DPAndCRLs, Options) -> CRLStatus()
Types:
OTPCertificate = #'OTPCertificate'{}
DPAndCRLs = [{DP::#'DistributionPoint'{}, {DerCRL::der_encoded(),
CRL::#'CertificateList'{}}}]
Options = proplists:proplist()
CRLStatus() = valid | {bad_cert, revocation_status_undetermined} | {bad_cert,
{revoked, crl_reason()}}
Performs CRL validation. It is intended to be called from the verify fun of
pkix_path_validation/3 .
Available options:
pkix_crl_verify(CRL, Cert) -> boolean()
- {update_crl, fun()}:
- The fun has the following type specification:
fun(#'DistributionPoint'{}, #'CertificateList'{}) -> #'CertificateList'{}
The fun uses the information in the distribution point to access the latest
possible version of the CRL. If this fun is not specified, Public Key uses the
default implementation:
fun(_DP, CRL) -> CRL end
- {issuer_fun, fun()}:
- The fun has the following type specification:
fun(#'DistributionPoint'{}, #'CertificateList'{}, {rdnSequence,[#'AttributeTypeAndValue'{}]}, term()) -> {ok, #'OTPCertificate'{}, [der_encoded]}
The fun returns the root certificate and certificate chain that has signed the
CRL.
fun(DP, CRL, Issuer, UserState) -> {ok, RootCert, CertChain}
Types:
CRL = der_encoded() | #'CertificateList'{}
Cert = der_encoded() | #'OTPCertificate'{}
Verify that Cert is the CRL signer.
pkix_dist_point(Cert) -> DistPoint
Types:
Cert = der_encoded() | #'OTPCertificate'{}
DistPoint = #'DistributionPoint'{}
Cert = der_encoded() | #'OTPCertificate'{}
DistPoint = #'DistributionPoint'{}
Creates a distribution point for CRLs issued by the same issuer as Cert.
Can be used as input to pkix_crls_validate/3
pkix_dist_points(Cert) -> DistPoints
Types:
Cert = der_encoded() | #'OTPCertificate'{}
DistPoints = [#'DistributionPoint'{}]
Cert = der_encoded() | #'OTPCertificate'{}
DistPoints = [#'DistributionPoint'{}]
Extracts distribution points from the certificates extensions.
pkix_match_dist_point(CRL, DistPoint) -> boolean()
Types:
CRL = der_encoded() | #'CertificateList'{}
DistPoint = #'DistributionPoint'{}
Checks whether the given distribution point matches the Issuing Distribution
Point of the CRL, as described in RFC 5280. If the CRL doesn't have an Issuing
Distribution Point extension, the distribution point always matches.
pkix_sign(#'OTPTBSCertificate'{}, Key) -> der_encoded()
Types:
Key = rsa_private_key() | dsa_private_key()
Signs an 'OTPTBSCertificate'. Returns the corresponding DER-encoded
certificate.
pkix_sign_types(AlgorithmId) -> {DigestType, SignatureType}
Types:
AlgorithmId = oid()
SignatureType = rsa | dsa | ecdsa
Signature OID from a certificate or a certificate
revocation list.
DigestType = rsa_digest_type() | dss_digest_type()
Translates signature algorithm OID to Erlang digest and signature types.
pkix_verify(Cert, Key) -> boolean()
Types:
Cert = der_encoded()
Key = rsa_public_key() | dsa_public_key() | ec_public_key()
Verifies PKIX x.509 certificate signature.
sign(Msg, DigestType, Key) -> binary()
Types:
Msg = binary() | {digest,binary()}
Key = rsa_private_key() | dsa_private_key() | ec_private_key()
The Msg is either the binary "plain
text" data to be signed or it is the hashed value of "plain
text", that is, the digest.
DigestType = rsa_digest_type() | dss_digest_type() | ecdsa_digest_type()
Creates a digital signature.
ssh_decode(SshBin, Type) -> [{public_key(), Attributes::list()}]
Types:
SshBin = binary()
Example {ok, SshBin} =
file:read_file("known_hosts").
Type = public_key | ssh_file()
If Type is public_key the binary can be
either an RFC4716 public key or an OpenSSH public key.
Decodes an SSH file-binary. In the case of known_hosts or
auth_keys, the binary can include one or more lines of the file.
Returns a list of public keys and their attributes, possible attribute values
depends on the file type represented by the binary.
ssh_encode([{Key, Attributes}], Type) -> binary()
- RFC4716 attributes - see RFC 4716.:
- {headers, [{string(), utf8_string()}]}
- auth_key attributes - see manual page for sshd.:
- {comment, string()}{options, [string()]}{bits, integer()} - In SSH version 1 files.
- known_host attributes - see manual page for sshd.:
- {hostnames, [string()]}{comment, string()}{bits, integer()} - In SSH version 1 files.
Types:
Key = public_key()
Attributes = list()
Type = ssh_file()
Encodes a list of SSH file entries (public keys and attributes) to a binary.
Possible attributes depend on the file type, see ssh_decode/2 .
ssh_hostkey_fingerprint(HostKey) -> string()
Types:
Key = public_key()
DigestType = digest_type()
Calculates a ssh fingerprint from a public host key as openssh does.
The algorithm in ssh_hostkey_fingerprint/1 is md5 to be compatible with
older ssh-keygen commands. The string from the second variant is prepended by
the algorithm name in uppercase as in newer ssh-keygen commands.
Examples:
verify(Msg, DigestType, Signature, Key) -> boolean()
2> public_key:ssh_hostkey_fingerprint(Key). "f5:64:a6:c1:5a:cb:9f:0a:10:46:a2:5c:3e:2f:57:84" 3> public_key:ssh_hostkey_fingerprint(md5,Key). "MD5:f5:64:a6:c1:5a:cb:9f:0a:10:46:a2:5c:3e:2f:57:84" 4> public_key:ssh_hostkey_fingerprint(sha,Key). "SHA1:bSLY/C4QXLDL/Iwmhyg0PGW9UbY" 5> public_key:ssh_hostkey_fingerprint(sha256,Key). "SHA256:aZGXhabfbf4oxglxltItWeHU7ub3Dc31NcNw2cMJePQ"
Types:
Msg = binary() | {digest,binary()}
Signature = binary()
Key = rsa_public_key() | dsa_public_key() | ec_public_key()
The Msg is either the binary "plain
text" data or it is the hashed value of "plain text", that is,
the digest.
DigestType = rsa_digest_type() | dss_digest_type() | ecdsa_digest_type()
Verifies a digital signature.
short_name_hash(Name) -> string()
Types:
Name = issuer_name()
Generates a short hash of an issuer name. The hash is returned as a string
containing eight hexadecimal digits.
The return value of this function is the same as the result of the commands
openssl crl -hash and openssl x509 -issuer_hash, when passed the
issuer name of a CRL or a certificate, respectively. This hash is used by the
c_rehash tool to maintain a directory of symlinks to CRL files, in
order to facilitate looking up a CRL by its issuer name.
public_key 1.3 | Ericsson AB |