xref: /openbsd-src/usr.bin/ssh/sshkey.h (revision c7e8ea31cd41a963f06f0a8ba93948b06aa6b4a4)
1 /* $OpenBSD: sshkey.h,v 1.21 2017/07/01 13:50:45 djm Exp $ */
2 
3 /*
4  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 #ifndef SSHKEY_H
27 #define SSHKEY_H
28 
29 #include <sys/types.h>
30 
31 #ifdef WITH_OPENSSL
32 #include <openssl/rsa.h>
33 #include <openssl/dsa.h>
34 #include <openssl/ec.h>
35 #else /* OPENSSL */
36 #define RSA		void
37 #define DSA		void
38 #define EC_KEY		void
39 #define EC_GROUP	void
40 #define EC_POINT	void
41 #endif /* WITH_OPENSSL */
42 
43 #define SSH_RSA_MINIMUM_MODULUS_SIZE	1024
44 #define SSH_KEY_MAX_SIGN_DATA_SIZE	(1 << 20)
45 
46 struct sshbuf;
47 
48 /* Key types */
49 enum sshkey_types {
50 	KEY_RSA,
51 	KEY_DSA,
52 	KEY_ECDSA,
53 	KEY_ED25519,
54 	KEY_RSA_CERT,
55 	KEY_DSA_CERT,
56 	KEY_ECDSA_CERT,
57 	KEY_ED25519_CERT,
58 	KEY_UNSPEC
59 };
60 
61 /* Default fingerprint hash */
62 #define SSH_FP_HASH_DEFAULT	SSH_DIGEST_SHA256
63 
64 /* Fingerprint representation formats */
65 enum sshkey_fp_rep {
66 	SSH_FP_DEFAULT = 0,
67 	SSH_FP_HEX,
68 	SSH_FP_BASE64,
69 	SSH_FP_BUBBLEBABBLE,
70 	SSH_FP_RANDOMART
71 };
72 
73 /* key is stored in external hardware */
74 #define SSHKEY_FLAG_EXT		0x0001
75 
76 #define SSHKEY_CERT_MAX_PRINCIPALS	256
77 /* XXX opaquify? */
78 struct sshkey_cert {
79 	struct sshbuf	*certblob; /* Kept around for use on wire */
80 	u_int		 type; /* SSH2_CERT_TYPE_USER or SSH2_CERT_TYPE_HOST */
81 	u_int64_t	 serial;
82 	char		*key_id;
83 	u_int		 nprincipals;
84 	char		**principals;
85 	u_int64_t	 valid_after, valid_before;
86 	struct sshbuf	*critical;
87 	struct sshbuf	*extensions;
88 	struct sshkey	*signature_key;
89 };
90 
91 /* XXX opaquify? */
92 struct sshkey {
93 	int	 type;
94 	int	 flags;
95 	RSA	*rsa;
96 	DSA	*dsa;
97 	int	 ecdsa_nid;	/* NID of curve */
98 	EC_KEY	*ecdsa;
99 	u_char	*ed25519_sk;
100 	u_char	*ed25519_pk;
101 	struct sshkey_cert *cert;
102 };
103 
104 #define	ED25519_SK_SZ	crypto_sign_ed25519_SECRETKEYBYTES
105 #define	ED25519_PK_SZ	crypto_sign_ed25519_PUBLICKEYBYTES
106 
107 struct sshkey	*sshkey_new(int);
108 int		 sshkey_add_private(struct sshkey *);
109 struct sshkey	*sshkey_new_private(int);
110 void		 sshkey_free(struct sshkey *);
111 int		 sshkey_demote(const struct sshkey *, struct sshkey **);
112 int		 sshkey_equal_public(const struct sshkey *,
113     const struct sshkey *);
114 int		 sshkey_equal(const struct sshkey *, const struct sshkey *);
115 char		*sshkey_fingerprint(const struct sshkey *,
116     int, enum sshkey_fp_rep);
117 int		 sshkey_fingerprint_raw(const struct sshkey *k,
118     int, u_char **retp, size_t *lenp);
119 const char	*sshkey_type(const struct sshkey *);
120 const char	*sshkey_cert_type(const struct sshkey *);
121 int		 sshkey_format_text(const struct sshkey *, struct sshbuf *);
122 int		 sshkey_write(const struct sshkey *, FILE *);
123 int		 sshkey_read(struct sshkey *, char **);
124 u_int		 sshkey_size(const struct sshkey *);
125 
126 int		 sshkey_generate(int type, u_int bits, struct sshkey **keyp);
127 int		 sshkey_from_private(const struct sshkey *, struct sshkey **);
128 int	 sshkey_type_from_name(const char *);
129 int	 sshkey_is_cert(const struct sshkey *);
130 int	 sshkey_type_is_cert(int);
131 int	 sshkey_type_plain(int);
132 int	 sshkey_to_certified(struct sshkey *);
133 int	 sshkey_drop_cert(struct sshkey *);
134 int	 sshkey_cert_copy(const struct sshkey *, struct sshkey *);
135 int	 sshkey_cert_check_authority(const struct sshkey *, int, int,
136     const char *, const char **);
137 size_t	 sshkey_format_cert_validity(const struct sshkey_cert *,
138     char *, size_t) __attribute__((__bounded__(__string__, 2, 3)));
139 
140 int	 sshkey_certify(struct sshkey *, struct sshkey *, const char *);
141 /* Variant allowing use of a custom signature function (e.g. for ssh-agent) */
142 typedef int sshkey_certify_signer(const struct sshkey *, u_char **, size_t *,
143     const u_char *, size_t, const char *, u_int, void *);
144 int	 sshkey_certify_custom(struct sshkey *, struct sshkey *, const char *,
145     sshkey_certify_signer *, void *);
146 
147 int		 sshkey_ecdsa_nid_from_name(const char *);
148 int		 sshkey_curve_name_to_nid(const char *);
149 const char *	 sshkey_curve_nid_to_name(int);
150 u_int		 sshkey_curve_nid_to_bits(int);
151 int		 sshkey_ecdsa_bits_to_nid(int);
152 int		 sshkey_ecdsa_key_to_nid(EC_KEY *);
153 int		 sshkey_ec_nid_to_hash_alg(int nid);
154 int		 sshkey_ec_validate_public(const EC_GROUP *, const EC_POINT *);
155 int		 sshkey_ec_validate_private(const EC_KEY *);
156 const char	*sshkey_ssh_name(const struct sshkey *);
157 const char	*sshkey_ssh_name_plain(const struct sshkey *);
158 int		 sshkey_names_valid2(const char *, int);
159 char		*sshkey_alg_list(int, int, int, char);
160 
161 int	 sshkey_from_blob(const u_char *, size_t, struct sshkey **);
162 int	 sshkey_fromb(struct sshbuf *, struct sshkey **);
163 int	 sshkey_froms(struct sshbuf *, struct sshkey **);
164 int	 sshkey_to_blob(const struct sshkey *, u_char **, size_t *);
165 int	 sshkey_to_base64(const struct sshkey *, char **);
166 int	 sshkey_putb(const struct sshkey *, struct sshbuf *);
167 int	 sshkey_puts(const struct sshkey *, struct sshbuf *);
168 int	 sshkey_plain_to_blob(const struct sshkey *, u_char **, size_t *);
169 int	 sshkey_putb_plain(const struct sshkey *, struct sshbuf *);
170 
171 int	 sshkey_sign(const struct sshkey *, u_char **, size_t *,
172     const u_char *, size_t, const char *, u_int);
173 int	 sshkey_verify(const struct sshkey *, const u_char *, size_t,
174     const u_char *, size_t, u_int);
175 
176 /* for debug */
177 void	sshkey_dump_ec_point(const EC_GROUP *, const EC_POINT *);
178 void	sshkey_dump_ec_key(const EC_KEY *);
179 
180 /* private key parsing and serialisation */
181 int	sshkey_private_serialize(const struct sshkey *key, struct sshbuf *buf);
182 int	sshkey_private_deserialize(struct sshbuf *buf,  struct sshkey **keyp);
183 
184 /* private key file format parsing and serialisation */
185 int	sshkey_private_to_fileblob(struct sshkey *key, struct sshbuf *blob,
186     const char *passphrase, const char *comment,
187     int force_new_format, const char *new_format_cipher, int new_format_rounds);
188 int	sshkey_parse_private_fileblob(struct sshbuf *buffer,
189     const char *passphrase, struct sshkey **keyp, char **commentp);
190 int	sshkey_parse_private_fileblob_type(struct sshbuf *blob, int type,
191     const char *passphrase, struct sshkey **keyp, char **commentp);
192 
193 /* XXX should be internal, but used by ssh-keygen */
194 int ssh_rsa_generate_additional_parameters(struct sshkey *);
195 
196 #ifdef SSHKEY_INTERNAL
197 int ssh_rsa_sign(const struct sshkey *key,
198     u_char **sigp, size_t *lenp, const u_char *data, size_t datalen,
199     const char *ident);
200 int ssh_rsa_verify(const struct sshkey *key,
201     const u_char *sig, size_t siglen, const u_char *data, size_t datalen);
202 int ssh_dss_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
203     const u_char *data, size_t datalen, u_int compat);
204 int ssh_dss_verify(const struct sshkey *key,
205     const u_char *signature, size_t signaturelen,
206     const u_char *data, size_t datalen, u_int compat);
207 int ssh_ecdsa_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
208     const u_char *data, size_t datalen, u_int compat);
209 int ssh_ecdsa_verify(const struct sshkey *key,
210     const u_char *signature, size_t signaturelen,
211     const u_char *data, size_t datalen, u_int compat);
212 int ssh_ed25519_sign(const struct sshkey *key, u_char **sigp, size_t *lenp,
213     const u_char *data, size_t datalen, u_int compat);
214 int ssh_ed25519_verify(const struct sshkey *key,
215     const u_char *signature, size_t signaturelen,
216     const u_char *data, size_t datalen, u_int compat);
217 #endif
218 
219 #ifndef WITH_OPENSSL
220 #undef RSA
221 #undef DSA
222 #undef EC_KEY
223 #undef EC_GROUP
224 #undef EC_POINT
225 #endif /* WITH_OPENSSL */
226 
227 #endif /* SSHKEY_H */
228