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mirror of git://anongit.mindrot.org/openssh.git synced 2024-12-24 19:02:06 +00:00
openssh/sshkey.h
djm@openbsd.org c1c2ca1365
upstream: better validate CASignatureAlgorithms in ssh_config and
sshd_config.

Previously this directive would accept certificate algorithm names, but
these were unusable in practice as OpenSSH does not support CA chains.

part of bz3577; ok dtucker@

OpenBSD-Commit-ID: a992d410c8a78ec982701bc3f91043dbdb359912
2023-06-21 15:13:56 +10:00

352 lines
12 KiB
C

/* $OpenBSD: sshkey.h,v 1.62 2023/06/21 05:10:26 djm Exp $ */
/*
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SSHKEY_H
#define SSHKEY_H
#include <sys/types.h>
#ifdef WITH_OPENSSL
#include <openssl/rsa.h>
#include <openssl/dsa.h>
# ifdef OPENSSL_HAS_ECC
# include <openssl/ec.h>
# include <openssl/ecdsa.h>
# else /* OPENSSL_HAS_ECC */
# define EC_KEY void
# define EC_GROUP void
# define EC_POINT void
# endif /* OPENSSL_HAS_ECC */
#define SSH_OPENSSL_VERSION OpenSSL_version(OPENSSL_VERSION)
#else /* WITH_OPENSSL */
# define BIGNUM void
# define RSA void
# define DSA void
# define EC_KEY void
# define EC_GROUP void
# define EC_POINT void
#define SSH_OPENSSL_VERSION "without OpenSSL"
#endif /* WITH_OPENSSL */
#define SSH_RSA_MINIMUM_MODULUS_SIZE 1024
#define SSH_KEY_MAX_SIGN_DATA_SIZE (1 << 20)
struct sshbuf;
/* Key types */
enum sshkey_types {
KEY_RSA,
KEY_DSA,
KEY_ECDSA,
KEY_ED25519,
KEY_RSA_CERT,
KEY_DSA_CERT,
KEY_ECDSA_CERT,
KEY_ED25519_CERT,
KEY_XMSS,
KEY_XMSS_CERT,
KEY_ECDSA_SK,
KEY_ECDSA_SK_CERT,
KEY_ED25519_SK,
KEY_ED25519_SK_CERT,
KEY_UNSPEC
};
/* Default fingerprint hash */
#define SSH_FP_HASH_DEFAULT SSH_DIGEST_SHA256
/* Fingerprint representation formats */
enum sshkey_fp_rep {
SSH_FP_DEFAULT = 0,
SSH_FP_HEX,
SSH_FP_BASE64,
SSH_FP_BUBBLEBABBLE,
SSH_FP_RANDOMART
};
/* Private key serialisation formats, used on the wire */
enum sshkey_serialize_rep {
SSHKEY_SERIALIZE_DEFAULT = 0,
SSHKEY_SERIALIZE_STATE = 1, /* only state is serialized */
SSHKEY_SERIALIZE_FULL = 2, /* include keys for saving to disk */
SSHKEY_SERIALIZE_SHIELD = 3, /* everything, for encrypting in ram */
SSHKEY_SERIALIZE_INFO = 254, /* minimal information */
};
/* Private key disk formats */
enum sshkey_private_format {
SSHKEY_PRIVATE_OPENSSH = 0,
SSHKEY_PRIVATE_PEM = 1,
SSHKEY_PRIVATE_PKCS8 = 2,
};
/* key is stored in external hardware */
#define SSHKEY_FLAG_EXT 0x0001
#define SSHKEY_CERT_MAX_PRINCIPALS 256
/* XXX opaquify? */
struct sshkey_cert {
struct sshbuf *certblob; /* Kept around for use on wire */
u_int type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */
u_int64_t serial;
char *key_id;
u_int nprincipals;
char **principals;
u_int64_t valid_after, valid_before;
struct sshbuf *critical;
struct sshbuf *extensions;
struct sshkey *signature_key;
char *signature_type;
};
/* XXX opaquify? */
struct sshkey {
int type;
int flags;
/* KEY_RSA */
RSA *rsa;
/* KEY_DSA */
DSA *dsa;
/* KEY_ECDSA and KEY_ECDSA_SK */
int ecdsa_nid; /* NID of curve */
EC_KEY *ecdsa;
/* KEY_ED25519 and KEY_ED25519_SK */
u_char *ed25519_sk;
u_char *ed25519_pk;
/* KEY_XMSS */
char *xmss_name;
char *xmss_filename; /* for state file updates */
void *xmss_state; /* depends on xmss_name, opaque */
u_char *xmss_sk;
u_char *xmss_pk;
/* KEY_ECDSA_SK and KEY_ED25519_SK */
char *sk_application;
uint8_t sk_flags;
struct sshbuf *sk_key_handle;
struct sshbuf *sk_reserved;
/* Certificates */
struct sshkey_cert *cert;
/* Private key shielding */
u_char *shielded_private;
size_t shielded_len;
u_char *shield_prekey;
size_t shield_prekey_len;
};
#define ED25519_SK_SZ crypto_sign_ed25519_SECRETKEYBYTES
#define ED25519_PK_SZ crypto_sign_ed25519_PUBLICKEYBYTES
/* Additional fields contained in signature */
struct sshkey_sig_details {
uint32_t sk_counter; /* U2F signature counter */
uint8_t sk_flags; /* U2F signature flags; see ssh-sk.h */
};
struct sshkey_impl_funcs {
u_int (*size)(const struct sshkey *); /* optional */
int (*alloc)(struct sshkey *); /* optional */
void (*cleanup)(struct sshkey *); /* optional */
int (*equal)(const struct sshkey *, const struct sshkey *);
int (*serialize_public)(const struct sshkey *, struct sshbuf *,
enum sshkey_serialize_rep);
int (*deserialize_public)(const char *, struct sshbuf *,
struct sshkey *);
int (*serialize_private)(const struct sshkey *, struct sshbuf *,
enum sshkey_serialize_rep);
int (*deserialize_private)(const char *, struct sshbuf *,
struct sshkey *);
int (*generate)(struct sshkey *, int); /* optional */
int (*copy_public)(const struct sshkey *, struct sshkey *);
int (*sign)(struct sshkey *, u_char **, size_t *,
const u_char *, size_t, const char *,
const char *, const char *, u_int); /* optional */
int (*verify)(const struct sshkey *, const u_char *, size_t,
const u_char *, size_t, const char *, u_int,
struct sshkey_sig_details **);
};
struct sshkey_impl {
const char *name;
const char *shortname;
const char *sigalg;
int type;
int nid;
int cert;
int sigonly;
int keybits;
const struct sshkey_impl_funcs *funcs;
};
struct sshkey *sshkey_new(int);
void sshkey_free(struct sshkey *);
int sshkey_equal_public(const struct sshkey *,
const struct sshkey *);
int sshkey_equal(const struct sshkey *, const struct sshkey *);
char *sshkey_fingerprint(const struct sshkey *,
int, enum sshkey_fp_rep);
int sshkey_fingerprint_raw(const struct sshkey *k,
int, u_char **retp, size_t *lenp);
const char *sshkey_type(const struct sshkey *);
const char *sshkey_cert_type(const struct sshkey *);
int sshkey_format_text(const struct sshkey *, struct sshbuf *);
int sshkey_write(const struct sshkey *, FILE *);
int sshkey_read(struct sshkey *, char **);
u_int sshkey_size(const struct sshkey *);
int sshkey_generate(int type, u_int bits, struct sshkey **keyp);
int sshkey_from_private(const struct sshkey *, struct sshkey **);
int sshkey_is_shielded(struct sshkey *);
int sshkey_shield_private(struct sshkey *);
int sshkey_unshield_private(struct sshkey *);
int sshkey_type_from_name(const char *);
int sshkey_is_cert(const struct sshkey *);
int sshkey_is_sk(const struct sshkey *);
int sshkey_type_is_cert(int);
int sshkey_type_plain(int);
/* Returns non-zero if key name match sigalgs pattern list. (handles RSA) */
int sshkey_match_keyname_to_sigalgs(const char *, const char *);
int sshkey_to_certified(struct sshkey *);
int sshkey_drop_cert(struct sshkey *);
int sshkey_cert_copy(const struct sshkey *, struct sshkey *);
int sshkey_cert_check_authority(const struct sshkey *, int, int, int,
uint64_t, const char *, const char **);
int sshkey_cert_check_authority_now(const struct sshkey *, int, int, int,
const char *, const char **);
int sshkey_cert_check_host(const struct sshkey *, const char *,
int , const char *, const char **);
size_t sshkey_format_cert_validity(const struct sshkey_cert *,
char *, size_t) __attribute__((__bounded__(__string__, 2, 3)));
int sshkey_check_cert_sigtype(const struct sshkey *, const char *);
int sshkey_certify(struct sshkey *, struct sshkey *,
const char *, const char *, const char *);
/* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
typedef int sshkey_certify_signer(struct sshkey *, u_char **, size_t *,
const u_char *, size_t, const char *, const char *, const char *,
u_int, void *);
int sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
const char *, const char *, sshkey_certify_signer *, void *);
int sshkey_ecdsa_nid_from_name(const char *);
int sshkey_curve_name_to_nid(const char *);
const char * sshkey_curve_nid_to_name(int);
u_int sshkey_curve_nid_to_bits(int);
int sshkey_ecdsa_bits_to_nid(int);
int sshkey_ecdsa_key_to_nid(EC_KEY *);
int sshkey_ec_nid_to_hash_alg(int nid);
int sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *);
int sshkey_ec_validate_private(const EC_KEY *);
const char *sshkey_ssh_name(const struct sshkey *);
const char *sshkey_ssh_name_plain(const struct sshkey *);
int sshkey_names_valid2(const char *, int, int);
char *sshkey_alg_list(int, int, int, char);
int sshkey_from_blob(const u_char *, size_t, struct sshkey **);
int sshkey_fromb(struct sshbuf *, struct sshkey **);
int sshkey_froms(struct sshbuf *, struct sshkey **);
int sshkey_to_blob(const struct sshkey *, u_char **, size_t *);
int sshkey_to_base64(const struct sshkey *, char **);
int sshkey_putb(const struct sshkey *, struct sshbuf *);
int sshkey_puts(const struct sshkey *, struct sshbuf *);
int sshkey_puts_opts(const struct sshkey *, struct sshbuf *,
enum sshkey_serialize_rep);
int sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
int sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
int sshkey_sign(struct sshkey *, u_char **, size_t *,
const u_char *, size_t, const char *, const char *, const char *, u_int);
int sshkey_verify(const struct sshkey *, const u_char *, size_t,
const u_char *, size_t, const char *, u_int, struct sshkey_sig_details **);
int sshkey_check_sigtype(const u_char *, size_t, const char *);
const char *sshkey_sigalg_by_name(const char *);
int sshkey_get_sigtype(const u_char *, size_t, char **);
/* for debug */
void sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *);
void sshkey_dump_ec_key(const EC_KEY *);
/* private key parsing and serialisation */
int sshkey_private_serialize(struct sshkey *key, struct sshbuf *buf);
int sshkey_private_serialize_opt(struct sshkey *key, struct sshbuf *buf,
enum sshkey_serialize_rep);
int sshkey_private_deserialize(struct sshbuf *buf, struct sshkey **keyp);
/* private key file format parsing and serialisation */
int sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
const char *passphrase, const char *comment,
int format, const char *openssh_format_cipher, int openssh_format_rounds);
int sshkey_parse_private_fileblob(struct sshbuf *buffer,
const char *passphrase, struct sshkey **keyp, char **commentp);
int sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
const char *passphrase, struct sshkey **keyp, char **commentp);
int sshkey_parse_pubkey_from_private_fileblob_type(struct sshbuf *blob,
int type, struct sshkey **pubkeyp);
int sshkey_check_rsa_length(const struct sshkey *, int);
/* XXX should be internal, but used by ssh-keygen */
int ssh_rsa_complete_crt_parameters(struct sshkey *, const BIGNUM *);
/* stateful keys (e.g. XMSS) */
int sshkey_set_filename(struct sshkey *, const char *);
int sshkey_enable_maxsign(struct sshkey *, u_int32_t);
u_int32_t sshkey_signatures_left(const struct sshkey *);
int sshkey_forward_state(const struct sshkey *, u_int32_t, int);
int sshkey_private_serialize_maxsign(struct sshkey *key,
struct sshbuf *buf, u_int32_t maxsign, int);
void sshkey_sig_details_free(struct sshkey_sig_details *);
#ifdef SSHKEY_INTERNAL
int sshkey_sk_fields_equal(const struct sshkey *a, const struct sshkey *b);
void sshkey_sk_cleanup(struct sshkey *k);
int sshkey_serialize_sk(const struct sshkey *key, struct sshbuf *b);
int sshkey_copy_public_sk(const struct sshkey *from, struct sshkey *to);
int sshkey_deserialize_sk(struct sshbuf *b, struct sshkey *key);
int sshkey_serialize_private_sk(const struct sshkey *key,
struct sshbuf *buf);
int sshkey_private_deserialize_sk(struct sshbuf *buf, struct sshkey *k);
#ifdef WITH_OPENSSL
int check_rsa_length(const RSA *rsa); /* XXX remove */
#endif
#endif
#if !defined(WITH_OPENSSL)
# undef RSA
# undef DSA
# undef EC_KEY
# undef EC_GROUP
# undef EC_POINT
#elif !defined(OPENSSL_HAS_ECC)
# undef EC_KEY
# undef EC_GROUP
# undef EC_POINT
#endif
#endif /* SSHKEY_H */