2 * Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
11 #include "internal/cryptlib.h"
12 #include <openssl/asn1t.h>
14 #if !(OPENSSL_API_COMPAT < 0x10200000L)
15 NON_EMPTY_TRANSLATION_UNIT
18 #define COPY_SIZE(a, b) (sizeof(a) < sizeof(b) ? sizeof(a) : sizeof(b))
21 * Custom primitive type for long handling. This converts between an
22 * ASN1_INTEGER and a long directly.
25 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
26 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
28 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
30 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
31 int utype, char *free_cont, const ASN1_ITEM *it);
32 static int long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
33 int indent, const ASN1_PCTX *pctx);
35 static ASN1_PRIMITIVE_FUNCS long_pf = {
39 long_free, /* Clear should set to initial value */
46 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, ASN1_LONG_UNDEF, "LONG"
49 ASN1_ITEM_start(ZLONG)
50 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, 0, "ZLONG"
53 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
55 memcpy(pval, &it->size, COPY_SIZE(*pval, it->size));
59 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
61 memcpy(pval, &it->size, COPY_SIZE(*pval, it->size));
65 * Originally BN_num_bits_word was called to perform this operation, but
66 * trouble is that there is no guarantee that sizeof(long) equals to
67 * sizeof(BN_ULONG). BN_ULONG is a configurable type that can be as wide
68 * as long, but also double or half...
70 static int num_bits_ulong(unsigned long value)
73 unsigned long ret = 0;
76 * It is argued that *on average* constant counter loop performs
77 * not worse [if not better] than one with conditional break or
78 * mask-n-table-lookup-style, because of branch misprediction
81 for (i = 0; i < sizeof(value) * 8; i++) {
89 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
93 unsigned long utmp, sign;
96 memcpy(<mp, pval, COPY_SIZE(*pval, ltmp));
100 * Convert the long to positive: we subtract one if negative so we can
101 * cleanly handle the padding if only the MSB of the leading octet is
106 utmp = 0 - (unsigned long)ltmp - 1;
111 clen = num_bits_ulong(utmp);
112 /* If MSB of leading octet set we need to pad */
118 /* Convert number of bits to number of octets */
119 clen = (clen + 7) >> 3;
123 *cont++ = (unsigned char)sign;
124 for (i = clen - 1; i >= 0; i--) {
125 cont[i] = (unsigned char)(utmp ^ sign);
132 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
133 int utype, char *free_cont, const ASN1_ITEM *it)
137 unsigned long utmp = 0, sign = 0x100;
141 * Check possible pad byte. Worst case, we're skipping past actual
142 * content, but since that's only with 0x00 and 0xff and we set neg
143 * accordingly, the result will be correct in the end anyway.
158 if (len > (int)sizeof(long)) {
159 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
164 /* Is it negative? */
165 if (len && (cont[0] & 0x80))
169 } else if (((sign ^ cont[0]) & 0x80) == 0) { /* same sign bit? */
170 ASN1err(ASN1_F_LONG_C2I, ASN1_R_ILLEGAL_PADDING);
174 for (i = 0; i < len; i++) {
176 utmp |= cont[i] ^ sign;
180 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
185 if (ltmp == it->size) {
186 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
189 memcpy(pval, <mp, COPY_SIZE(*pval, ltmp));
193 static int long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
194 int indent, const ASN1_PCTX *pctx)
198 memcpy(&l, pval, COPY_SIZE(*pval, l));
199 return BIO_printf(out, "%ld\n", l);