1 /*
2  * This file is part of the SSH Library
3  *
4  * Copyright (c) 2010 by Aris Adamantiadis
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef PKI_H_
22 #define PKI_H_
23 
24 #include "libssh/priv.h"
25 #ifdef HAVE_OPENSSL_EC_H
26 #include <openssl/ec.h>
27 #endif
28 #ifdef HAVE_OPENSSL_ECDSA_H
29 #include <openssl/ecdsa.h>
30 #endif
31 
32 #include "libssh/crypto.h"
33 #ifdef HAVE_OPENSSL_ED25519
34 /* If using OpenSSL implementation, define the signature lenght which would be
35  * defined in libssh/ed25519.h otherwise */
36 #define ED25519_SIG_LEN 64
37 #else
38 #include "libssh/ed25519.h"
39 #endif
40 /* This definition is used for both OpenSSL and internal implementations */
41 #define ED25519_KEY_LEN 32
42 
43 #define MAX_PUBKEY_SIZE 0x100000 /* 1M */
44 #define MAX_PRIVKEY_SIZE 0x400000 /* 4M */
45 
46 #define SSH_KEY_FLAG_EMPTY   0x0
47 #define SSH_KEY_FLAG_PUBLIC  0x0001
48 #define SSH_KEY_FLAG_PRIVATE 0x0002
49 
50 struct ssh_key_struct {
51     enum ssh_keytypes_e type;
52     int flags;
53     const char *type_c; /* Don't free it ! it is static */
54     int ecdsa_nid;
55 #if defined(HAVE_LIBGCRYPT)
56     gcry_sexp_t dsa;
57     gcry_sexp_t rsa;
58     gcry_sexp_t ecdsa;
59 #elif defined(HAVE_LIBMBEDCRYPTO)
60     mbedtls_pk_context *rsa;
61     mbedtls_ecdsa_context *ecdsa;
62     void *dsa;
63 #elif defined(HAVE_LIBCRYPTO)
64     DSA *dsa;
65     RSA *rsa;
66 # if defined(HAVE_OPENSSL_ECC)
67     EC_KEY *ecdsa;
68 # else
69     void *ecdsa;
70 # endif /* HAVE_OPENSSL_EC_H */
71 #endif /* HAVE_LIBGCRYPT */
72 #ifdef HAVE_OPENSSL_ED25519
73     uint8_t *ed25519_pubkey;
74     uint8_t *ed25519_privkey;
75 #else
76     ed25519_pubkey *ed25519_pubkey;
77     ed25519_privkey *ed25519_privkey;
78 #endif
79     void *cert;
80     enum ssh_keytypes_e cert_type;
81 };
82 
83 struct ssh_signature_struct {
84     enum ssh_keytypes_e type;
85     enum ssh_digest_e hash_type;
86     const char *type_c;
87 #if defined(HAVE_LIBGCRYPT)
88     gcry_sexp_t dsa_sig;
89     gcry_sexp_t rsa_sig;
90     gcry_sexp_t ecdsa_sig;
91 #elif defined(HAVE_LIBMBEDCRYPTO)
92     ssh_string rsa_sig;
93     struct mbedtls_ecdsa_sig ecdsa_sig;
94 #endif /* HAVE_LIBGCRYPT */
95 #ifndef HAVE_OPENSSL_ED25519
96     ed25519_signature *ed25519_sig;
97 #endif
98     ssh_string raw_sig;
99 };
100 
101 typedef struct ssh_signature_struct *ssh_signature;
102 
103 /* SSH Key Functions */
104 ssh_key ssh_key_dup(const ssh_key key);
105 void ssh_key_clean (ssh_key key);
106 
107 const char *
108 ssh_key_get_signature_algorithm(ssh_session session,
109                                 enum ssh_keytypes_e type);
110 enum ssh_keytypes_e ssh_key_type_from_signature_name(const char *name);
111 enum ssh_keytypes_e ssh_key_type_plain(enum ssh_keytypes_e type);
112 enum ssh_digest_e ssh_key_type_to_hash(ssh_session session,
113                                        enum ssh_keytypes_e type);
114 enum ssh_digest_e ssh_key_hash_from_name(const char *name);
115 
116 #define is_ecdsa_key_type(t) \
117     ((t) >= SSH_KEYTYPE_ECDSA_P256 && (t) <= SSH_KEYTYPE_ECDSA_P521)
118 
119 #define is_cert_type(kt)\
120       ((kt) == SSH_KEYTYPE_DSS_CERT01 ||\
121        (kt) == SSH_KEYTYPE_RSA_CERT01 ||\
122       ((kt) >= SSH_KEYTYPE_ECDSA_P256_CERT01 &&\
123        (kt) <= SSH_KEYTYPE_ED25519_CERT01))
124 
125 /* SSH Signature Functions */
126 ssh_signature ssh_signature_new(void);
127 void ssh_signature_free(ssh_signature sign);
128 #define SSH_SIGNATURE_FREE(x) \
129     do { ssh_signature_free(x); x = NULL; } while(0)
130 
131 int ssh_pki_export_signature_blob(const ssh_signature sign,
132                                   ssh_string *sign_blob);
133 int ssh_pki_import_signature_blob(const ssh_string sig_blob,
134                                   const ssh_key pubkey,
135                                   ssh_signature *psig);
136 int ssh_pki_signature_verify(ssh_session session,
137                              ssh_signature sig,
138                              const ssh_key key,
139                              const unsigned char *digest,
140                              size_t dlen);
141 
142 /* SSH Public Key Functions */
143 int ssh_pki_export_pubkey_blob(const ssh_key key,
144                                ssh_string *pblob);
145 int ssh_pki_import_pubkey_blob(const ssh_string key_blob,
146                                ssh_key *pkey);
147 
148 int ssh_pki_import_cert_blob(const ssh_string cert_blob,
149                              ssh_key *pkey);
150 
151 
152 /* SSH Signing Functions */
153 ssh_string ssh_pki_do_sign(ssh_session session, ssh_buffer sigbuf,
154     const ssh_key privatekey, enum ssh_digest_e hash_type);
155 ssh_string ssh_pki_do_sign_agent(ssh_session session,
156                                  struct ssh_buffer_struct *buf,
157                                  const ssh_key pubkey);
158 ssh_string ssh_srv_pki_do_sign_sessionid(ssh_session session,
159                                          const ssh_key privkey,
160                                          const enum ssh_digest_e digest);
161 
162 /* Temporary functions, to be removed after migration to ssh_key */
163 ssh_public_key ssh_pki_convert_key_to_publickey(const ssh_key key);
164 ssh_private_key ssh_pki_convert_key_to_privatekey(const ssh_key key);
165 
166 int ssh_key_algorithm_allowed(ssh_session session, const char *type);
167 #endif /* PKI_H_ */
168