5 Any deprecated keypair/params d2i or i2d functions are collected on this page.
12 d2i_DSAPrivateKey_bio,
20 d2i_RSAPrivateKey_bio,
32 i2d_RSAPrivateKey_bio,
49 Deprecated since OpenSSL 3.0, can be hidden entirely by defining
50 B<OPENSSL_API_COMPAT> with a suitable version value, see
51 L<openssl_user_macros(7)>:
53 TYPE *d2i_TYPEPrivateKey(TYPE **a, const unsigned char **ppin, long length);
54 TYPE *d2i_TYPEPrivateKey_bio(BIO *bp, TYPE **a);
55 TYPE *d2i_TYPEPrivateKey_fp(FILE *fp, TYPE **a);
56 TYPE *d2i_TYPEPublicKey(TYPE **a, const unsigned char **ppin, long length);
57 TYPE *d2i_TYPEPublicKey_bio(BIO *bp, TYPE **a);
58 TYPE *d2i_TYPEPublicKey_fp(FILE *fp, TYPE **a);
59 TYPE *d2i_TYPEparams(TYPE **a, const unsigned char **ppin, long length);
60 TYPE *d2i_TYPEparams_bio(BIO *bp, TYPE **a);
61 TYPE *d2i_TYPEparams_fp(FILE *fp, TYPE **a);
62 TYPE *d2i_TYPE_PUBKEY(TYPE **a, const unsigned char **ppin, long length);
63 TYPE *d2i_TYPE_PUBKEY_bio(BIO *bp, TYPE **a);
64 TYPE *d2i_TYPE_PUBKEY_fp(FILE *fp, TYPE **a);
66 int i2d_TYPEPrivateKey(const TYPE *a, unsigned char **ppout);
67 int i2d_TYPEPrivateKey(TYPE *a, unsigned char **ppout);
68 int i2d_TYPEPrivateKey_fp(FILE *fp, const TYPE *a);
69 int i2d_TYPEPrivateKey_fp(FILE *fp, TYPE *a);
70 int i2d_TYPEPrivateKey_bio(BIO *bp, const TYPE *a);
71 int i2d_TYPEPrivateKey_bio(BIO *bp, TYPE *a);
72 int i2d_TYPEPublicKey(const TYPE *a, unsigned char **ppout);
73 int i2d_TYPEPublicKey(TYPE *a, unsigned char **ppout);
74 int i2d_TYPEPublicKey_fp(FILE *fp, const TYPE *a);
75 int i2d_TYPEPublicKey_fp(FILE *fp, TYPE *a);
76 int i2d_TYPEPublicKey_bio(BIO *bp, const TYPE *a);
77 int i2d_TYPEPublicKey_bio(BIO *bp, TYPE *a);
78 int i2d_TYPEparams(const TYPE *a, unsigned char **ppout);
79 int i2d_TYPEparams(TYPE *a, unsigned char **ppout);
80 int i2d_TYPEparams_fp(FILE *fp, const TYPE *a);
81 int i2d_TYPEparams_fp(FILE *fp, TYPE *a);
82 int i2d_TYPEparams_bio(BIO *bp, const TYPE *a);
83 int i2d_TYPEparams_bio(BIO *bp, TYPE *a);
84 int i2d_TYPE_PUBKEY(const TYPE *a, unsigned char **ppout);
85 int i2d_TYPE_PUBKEY(TYPE *a, unsigned char **ppout);
86 int i2d_TYPE_PUBKEY_fp(FILE *fp, const TYPE *a);
87 int i2d_TYPE_PUBKEY_fp(FILE *fp, TYPE *a);
88 int i2d_TYPE_PUBKEY_bio(BIO *bp, const TYPE *a);
89 int i2d_TYPE_PUBKEY_bio(BIO *bp, TYPE *a);
93 All functions described here are deprecated. Please use L<OSSL_DECODER(3)>
94 instead of the B<d2i> functions and L<OSSL_ENCODER(3)> instead of the B<i2d>
95 functions. See L</Migration> below.
97 In the description here, B<I<TYPE>> is used a placeholder for any of the
98 OpenSSL datatypes, such as B<RSA>.
99 The function parameters I<ppin> and I<ppout> are generally either both named
100 I<pp> in the headers, or I<in> and I<out>.
102 All the functions here behave the way that's described in L<d2i_X509(3)>.
104 Please note that not all functions in the synopsis are available for all key
105 types. For example, there are no d2i_RSAparams() or i2d_RSAparams(),
106 because the PKCS#1 B<RSA> structure doesn't include any key parameters.
108 B<d2i_I<TYPE>PrivateKey>() and derivates thereof decode DER encoded
109 B<I<TYPE>> private key data organized in a type specific structure.
111 B<d2i_I<TYPE>PublicKey>() and derivates thereof decode DER encoded
112 B<I<TYPE>> public key data organized in a type specific structure.
114 B<d2i_I<TYPE>params>() and derivates thereof decode DER encoded B<I<TYPE>>
115 key parameters organized in a type specific structure.
117 B<d2i_I<TYPE>_PUBKEY>() and derivates thereof decode DER encoded B<I<TYPE>>
118 public key data organized in a B<SubjectPublicKeyInfo> structure.
120 B<i2d_I<TYPE>PrivateKey>() and derivates thereof encode the private key
121 B<I<TYPE>> data into a type specific DER encoded structure.
123 B<i2d_I<TYPE>PublicKey>() and derivates thereof encode the public key
124 B<I<TYPE>> data into a type specific DER encoded structure.
126 B<i2d_I<TYPE>params>() and derivates thereof encode the B<I<TYPE>> key
127 parameters data into a type specific DER encoded structure.
129 B<i2d_I<TYPE>_PUBKEY>() and derivates thereof encode the public key
130 B<I<TYPE>> data into a DER encoded B<SubjectPublicKeyInfo> structure.
132 For example, d2i_RSAPrivateKey() and d2i_RSAPublicKey() expects the
133 structure defined by PKCS#1.
134 Similarly, i2d_RSAPrivateKey() and i2d_RSAPublicKey() produce DER encoded
135 string organized according to PKCS#1.
139 Migration from the diverse B<I<TYPE>>s requires using corresponding new
140 OpenSSL types. For all B<I<TYPE>>s described here, the corresponding new
141 type is B<EVP_PKEY>. The rest of this section assumes that this has been
142 done, exactly how to do that is described elsewhere.
144 There are two migration paths:
151 b<d2i_I<TYPE>PrivateKey()> with L<d2i_PrivateKey(3)>,
152 b<d2i_I<TYPE>PublicKey()> with L<d2i_PublicKey(3)>,
153 b<d2i_I<TYPE>params()> with L<d2i_KeyParams(3)>,
154 b<d2i_I<TYPE>_PUBKEY()> with L<d2i_PUBKEY(3)>,
155 b<i2d_I<TYPE>PrivateKey()> with L<i2d_PrivateKey(3)>,
156 b<i2d_I<TYPE>PublicKey()> with L<i2d_PublicKey(3)>,
157 b<i2d_I<TYPE>params()> with L<i2d_KeyParams(3)>,
158 b<i2d_I<TYPE>_PUBKEY()> with L<i2d_PUBKEY(3)>.
159 A caveat is that L<i2d_PrivateKey(3)> may output a DER encoded PKCS#8
160 outermost structure instead of the type specific structure, and that
161 L<d2i_PrivateKey(3)> recognises and unpacks a PKCS#8 structures.
165 Use L<OSSL_DECODER(3)> and L<OSSL_ENCODER(3)>. How to migrate is described
166 below. All those descriptions assume that the key to be encoded is in the
171 =head3 Migrating B<i2d> functions to B<OSSL_ENCODER>
173 The exact L<OSSL_ENCODER(3)> output is driven by arguments rather than by
174 function names. The sample code to get DER encoded output in a type
175 specific structure is uniform, the only things that vary are the selection
176 of what part of the B<EVP_PKEY> should be output, and the structure. The
177 B<i2d> functions names can therefore be translated into two variables,
178 I<selection> and I<structure> as follows:
182 =item B<i2d_I<TYPE>PrivateKey>() translates into:
184 int selection = EVP_PKEY_PRIVATE_KEY;
185 const char *structure = "type-specific";
187 =item B<i2d_I<TYPE>PublicKey>() translates into:
189 int selection = EVP_PKEY_PUBLIC_KEY;
190 const char *structure = "type-specific";
192 =item B<i2d_I<TYPE>params>() translates into:
194 int selection = EVP_PKEY_PARAMETERS;
195 const char *structure = "type-specific";
197 =item B<i2d_I<TYPE>_PUBKEY>() translates into:
199 int selection = EVP_PKEY_PUBLIC_KEY;
200 const char *structure = "SubjectPublicKeyInfo";
204 The following sample code does the rest of the work:
206 unsigned char *p = buffer; /* |buffer| is supplied by the caller */
207 size_t len = buffer_size; /* assumed be the size of |buffer| */
208 OSSL_ENCODER_CTX *ctx =
209 OSSL_ENCODER_CTX_new_by_EVP_PKEY(pkey, selection, "DER", structure,
212 /* fatal error handling */
214 if (OSSL_ENCODER_CTX_get_num_encoders(ctx) == 0) {
215 OSSL_ENCODER_CTX_free(ctx);
216 /* non-fatal error handling */
218 if (!OSSL_ENCODER_to_data(ctx, &p, &len)) {
219 OSSL_ENCODER_CTX_free(ctx);
222 OSSL_ENCODER_CTX_free(ctx);
224 =for comment TODO: a similar section on OSSL_DECODER is to be added
228 The letters B<i> and B<d> in B<i2d_I<TYPE>>() stand for
229 "internal" (that is, an internal C structure) and "DER" respectively.
230 So B<i2d_I<TYPE>>() converts from internal to DER.
232 The functions can also understand B<BER> forms.
234 The actual TYPE structure passed to B<i2d_I<TYPE>>() must be a valid
235 populated B<I<TYPE>> structure -- it B<cannot> simply be fed with an
236 empty structure such as that returned by TYPE_new().
238 The encoded data is in binary form and may contain embedded zeros.
239 Therefore, any FILE pointers or BIOs should be opened in binary mode.
240 Functions such as strlen() will B<not> return the correct length
241 of the encoded structure.
243 The ways that I<*ppin> and I<*ppout> are incremented after the operation
244 can trap the unwary. See the B<WARNINGS> section for some common
246 The reason for this-auto increment behaviour is to reflect a typical
247 usage of ASN1 functions: after one structure is encoded or decoded
248 another will be processed after it.
250 The following points about the data types might be useful:
256 Represents a DSA public key using a B<SubjectPublicKeyInfo> structure.
258 =item B<DSAPublicKey>, B<DSAPrivateKey>
260 Use a non-standard OpenSSL format and should be avoided; use B<DSA_PUBKEY>,
261 L<PEM_write_PrivateKey(3)>, or similar instead.
267 B<d2i_I<TYPE>>(), B<d2i_I<TYPE>_bio>() and B<d2i_I<TYPE>_fp>() return a valid
268 B<I<TYPE>> structure or NULL if an error occurs. If the "reuse" capability has
269 been used with a valid structure being passed in via I<a>, then the object is
270 freed in the event of error and I<*a> is set to NULL.
272 B<i2d_I<TYPE>>() returns the number of bytes successfully encoded or a negative
273 value if an error occurs.
275 B<i2d_I<TYPE>_bio>() and B<i2d_I<TYPE>_fp>() return 1 for success and 0 if an
280 L<OSSL_ENCODER(3)>, L<OSSL_DECODER(3)>,
281 L<d2i_PrivateKey(3)>, L<d2i_PublicKey(3)>, L<d2i_KeyParams(3)>,
283 L<i2d_PrivateKey(3)>, L<i2d_PublicKey(3)>, L<i2d_KeyParams(3)>,
288 Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
290 Licensed under the Apache License 2.0 (the "License"). You may not use
291 this file except in compliance with the License. You can obtain a copy
292 in the file LICENSE in the source distribution or at
293 L<https://www.openssl.org/source/license.html>.