2 * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
5 * Licensed under the Apache License 2.0 (the "License"). You may not use
6 * this file except in compliance with the License. You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
12 #include <openssl/ebcdic.h>
13 #include <openssl/err.h>
14 #include <openssl/params.h>
17 * When processing text to params, we're trying to be smart with numbers.
18 * Instead of handling each specific separate integer type, we use a bignum
19 * and ensure that it isn't larger than the expected size, and we then make
20 * sure it is the expected size... if there is one given.
21 * (if the size can be arbitrary, then we give whatever we have)
24 static int prepare_from_text(const OSSL_PARAM *paramdefs, const char *key,
25 const char *value, size_t value_n,
26 /* Output parameters */
27 const OSSL_PARAM **paramdef, int *ishex,
28 size_t *buf_n, BIGNUM **tmpbn, int *found)
35 * ishex is used to translate legacy style string controls in hex format
36 * to octet string parameters.
38 *ishex = strncmp(key, "hex", 3) == 0;
43 p = *paramdef = OSSL_PARAM_locate_const(paramdefs, key);
49 switch (p->data_type) {
50 case OSSL_PARAM_INTEGER:
51 case OSSL_PARAM_UNSIGNED_INTEGER:
53 r = BN_hex2bn(tmpbn, value);
55 r = BN_asc2bn(tmpbn, value);
57 if (r == 0 || *tmpbn == NULL)
60 if (p->data_type == OSSL_PARAM_UNSIGNED_INTEGER
61 && BN_is_negative(*tmpbn)) {
62 ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_INVALID_NEGATIVE_VALUE);
67 * 2's complement negate, part 1
69 * BN_bn2nativepad puts the absolute value of the number in the
70 * buffer, i.e. if it's negative, we need to deal with it. We do
71 * it by subtracting 1 here and inverting the bytes in
72 * construct_from_text() below.
73 * To subtract 1 from an absolute value of a negative number we
74 * actually have to add 1: -3 - 1 = -4, |-3| = 3 + 1 = 4.
76 if (p->data_type == OSSL_PARAM_INTEGER && BN_is_negative(*tmpbn)
77 && !BN_add_word(*tmpbn, 1)) {
81 buf_bits = (size_t)BN_num_bits(*tmpbn);
84 * Compensate for cases where the most significant bit in
85 * the resulting OSSL_PARAM buffer will be set after the
86 * BN_bn2nativepad() call, as the implied sign may not be
87 * correct after the second part of the 2's complement
88 * negation has been performed.
89 * We fix these cases by extending the buffer by one byte
90 * (8 bits), which will give some padding. The second part
91 * of the 2's complement negation will do the rest.
93 if (p->data_type == OSSL_PARAM_INTEGER && buf_bits % 8 == 0)
96 *buf_n = (buf_bits + 7) / 8;
99 * A zero data size means "arbitrary size", so only do the
100 * range checking if a size is specified.
102 if (p->data_size > 0) {
103 if (buf_bits > p->data_size * 8) {
104 ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_TOO_SMALL_BUFFER);
105 /* Since this is a different error, we don't break */
108 /* Change actual size to become the desired size. */
109 *buf_n = p->data_size;
112 case OSSL_PARAM_UTF8_STRING:
114 ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_INVALID_ARGUMENT);
117 *buf_n = strlen(value) + 1;
119 case OSSL_PARAM_OCTET_STRING:
121 *buf_n = strlen(value) >> 1;
131 static int construct_from_text(OSSL_PARAM *to, const OSSL_PARAM *paramdef,
132 const char *value, size_t value_n, int ishex,
133 void *buf, size_t buf_n, BIGNUM *tmpbn)
139 switch (paramdef->data_type) {
140 case OSSL_PARAM_INTEGER:
141 case OSSL_PARAM_UNSIGNED_INTEGER:
144 if ((new_value = OPENSSL_malloc(new_value_n)) == NULL) {
150 BN_bn2nativepad(tmpbn, buf, buf_n);
153 * 2's complement negation, part two.
155 * Because we did the first part on the BIGNUM itself, we can just
156 * invert all the bytes here and be done with it.
158 if (paramdef->data_type == OSSL_PARAM_INTEGER
159 && BN_is_negative(tmpbn)) {
163 for (cp = buf; i-- > 0; cp++)
167 case OSSL_PARAM_UTF8_STRING:
168 #ifdef CHARSET_EBCDIC
169 ebcdic2ascii(buf, value, buf_n);
171 strncpy(buf, value, buf_n);
173 /* Don't count the terminating NUL byte as data */
176 case OSSL_PARAM_OCTET_STRING:
180 if (!OPENSSL_hexstr2buf_ex(buf, buf_n, &l, value, ':'))
183 memcpy(buf, value, buf_n);
191 to->data_size = buf_n;
192 to->return_size = OSSL_PARAM_UNMODIFIED;
197 int OSSL_PARAM_allocate_from_text(OSSL_PARAM *to,
198 const OSSL_PARAM *paramdefs,
199 const char *key, const char *value,
200 size_t value_n, int *found)
202 const OSSL_PARAM *paramdef = NULL;
206 BIGNUM *tmpbn = NULL;
209 if (to == NULL || paramdefs == NULL)
212 if (!prepare_from_text(paramdefs, key, value, value_n,
213 ¶mdef, &ishex, &buf_n, &tmpbn, found))
216 if ((buf = OPENSSL_zalloc(buf_n > 0 ? buf_n : 1)) == NULL) {
217 ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
221 ok = construct_from_text(to, paramdef, value, value_n, ishex,