1 /*
2  * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /*
11  * Low level APIs are deprecated for public use, but still ok for
12  * internal use.
13  */
14 #include "internal/deprecated.h"
15 
16 #include <stdio.h>
17 #include "internal/cryptlib.h"
18 #include <openssl/evp.h>
19 #include <openssl/encoder.h>
20 #include <openssl/buffer.h>
21 #include <openssl/x509.h>
22 #include <openssl/rsa.h>         /* For i2d_RSAPublicKey */
23 #include <openssl/dsa.h>         /* For i2d_DSAPublicKey */
24 #include <openssl/ec.h>          /* For i2o_ECPublicKey */
25 #include "crypto/asn1.h"
26 #include "crypto/evp.h"
27 
28 struct type_and_structure_st {
29     const char *output_type;
30     const char *output_structure;
31 };
32 
i2d_provided(const EVP_PKEY * a,int selection,const struct type_and_structure_st * output_info,unsigned char ** pp)33 static int i2d_provided(const EVP_PKEY *a, int selection,
34                         const struct type_and_structure_st *output_info,
35                         unsigned char **pp)
36 {
37     int ret;
38 
39     for (ret = -1;
40          ret == -1 && output_info->output_type != NULL;
41          output_info++) {
42         /*
43          * The i2d_ calls don't take a boundary length for *pp.  However,
44          * OSSL_ENCODER_to_data() needs one, so we make one up.  Because
45          * OSSL_ENCODER_to_data() decrements this number by the amount of
46          * bytes written, we need to calculate the length written further
47          * down, when pp != NULL.
48          */
49         size_t len = INT_MAX;
50         int pp_was_NULL = (pp == NULL || *pp == NULL);
51         OSSL_ENCODER_CTX *ctx;
52 
53         ctx = OSSL_ENCODER_CTX_new_for_pkey(a, selection,
54                                             output_info->output_type,
55                                             output_info->output_structure,
56                                             NULL);
57         if (ctx == NULL)
58             return -1;
59         if (OSSL_ENCODER_to_data(ctx, pp, &len)) {
60             if (pp_was_NULL)
61                 ret = (int)len;
62             else
63                 ret = INT_MAX - (int)len;
64         }
65         OSSL_ENCODER_CTX_free(ctx);
66     }
67 
68     if (ret == -1)
69         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_TYPE);
70     return ret;
71 }
72 
i2d_KeyParams(const EVP_PKEY * a,unsigned char ** pp)73 int i2d_KeyParams(const EVP_PKEY *a, unsigned char **pp)
74 {
75     if (evp_pkey_is_provided(a)) {
76         static const struct type_and_structure_st output_info[] = {
77             { "DER", "type-specific" },
78             { NULL, }
79         };
80 
81         return i2d_provided(a, EVP_PKEY_KEY_PARAMETERS, output_info, pp);
82     }
83     if (a->ameth != NULL && a->ameth->param_encode != NULL)
84         return a->ameth->param_encode(a, pp);
85     ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_TYPE);
86     return -1;
87 }
88 
i2d_KeyParams_bio(BIO * bp,const EVP_PKEY * pkey)89 int i2d_KeyParams_bio(BIO *bp, const EVP_PKEY *pkey)
90 {
91     return ASN1_i2d_bio_of(EVP_PKEY, i2d_KeyParams, bp, pkey);
92 }
93 
94 static int
i2d_PrivateKey_impl(const EVP_PKEY * a,unsigned char ** pp,int traditional)95 i2d_PrivateKey_impl(const EVP_PKEY *a, unsigned char **pp, int traditional)
96 {
97     if (evp_pkey_is_provided(a)) {
98         static const struct type_and_structure_st trad_output_info[] = {
99             { "DER", "type-specific" },
100             { "DER", "PrivateKeyInfo" },
101             { NULL, }
102         };
103         const struct type_and_structure_st *oi = trad_output_info;
104 
105         if (!traditional)
106             ++oi;
107         return i2d_provided(a, EVP_PKEY_KEYPAIR, oi, pp);
108     }
109 
110     if (traditional && a->ameth != NULL && a->ameth->old_priv_encode != NULL)
111         return a->ameth->old_priv_encode(a, pp);
112 
113     if (a->ameth != NULL && a->ameth->priv_encode != NULL) {
114         PKCS8_PRIV_KEY_INFO *p8 = EVP_PKEY2PKCS8(a);
115         int ret = 0;
116 
117         if (p8 != NULL) {
118             ret = i2d_PKCS8_PRIV_KEY_INFO(p8, pp);
119             PKCS8_PRIV_KEY_INFO_free(p8);
120         }
121         return ret;
122     }
123     ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_PUBLIC_KEY_TYPE);
124     return -1;
125 }
126 
i2d_PrivateKey(const EVP_PKEY * a,unsigned char ** pp)127 int i2d_PrivateKey(const EVP_PKEY *a, unsigned char **pp)
128 {
129     return i2d_PrivateKey_impl(a, pp, 1);
130 }
131 
i2d_PKCS8PrivateKey(const EVP_PKEY * a,unsigned char ** pp)132 int i2d_PKCS8PrivateKey(const EVP_PKEY *a, unsigned char **pp)
133 {
134     return i2d_PrivateKey_impl(a, pp, 0);
135 }
136 
i2d_PublicKey(const EVP_PKEY * a,unsigned char ** pp)137 int i2d_PublicKey(const EVP_PKEY *a, unsigned char **pp)
138 {
139     if (evp_pkey_is_provided(a)) {
140         static const struct type_and_structure_st output_info[] = {
141             { "DER", "type-specific" },
142             { "blob", NULL },    /* for EC */
143             { NULL, }
144         };
145 
146         return i2d_provided(a, EVP_PKEY_PUBLIC_KEY, output_info, pp);
147     }
148     switch (EVP_PKEY_get_base_id(a)) {
149     case EVP_PKEY_RSA:
150         return i2d_RSAPublicKey(EVP_PKEY_get0_RSA(a), pp);
151 #ifndef OPENSSL_NO_DSA
152     case EVP_PKEY_DSA:
153         return i2d_DSAPublicKey(EVP_PKEY_get0_DSA(a), pp);
154 #endif
155 #ifndef OPENSSL_NO_EC
156     case EVP_PKEY_EC:
157         return i2o_ECPublicKey(EVP_PKEY_get0_EC_KEY(a), pp);
158 #endif
159     default:
160         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNSUPPORTED_PUBLIC_KEY_TYPE);
161         return -1;
162     }
163 }
164