2 * Copyright 2000-2016 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>
15 * Custom primitive type for long handling. This converts between an
16 * ASN1_INTEGER and a long directly.
19 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
20 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
22 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
24 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
25 int utype, char *free_cont, const ASN1_ITEM *it);
26 static int long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
27 int indent, const ASN1_PCTX *pctx);
29 static ASN1_PRIMITIVE_FUNCS long_pf = {
33 long_free, /* Clear should set to initial value */
40 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, ASN1_LONG_UNDEF, "LONG"
43 ASN1_ITEM_start(ZLONG)
44 ASN1_ITYPE_PRIMITIVE, V_ASN1_INTEGER, NULL, 0, &long_pf, 0, "ZLONG"
47 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
49 *(long *)pval = it->size;
53 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
55 *(long *)pval = it->size;
59 * Originally BN_num_bits_word was called to perform this operation, but
60 * trouble is that there is no guarantee that sizeof(long) equals to
61 * sizeof(BN_ULONG). BN_ULONG is a configurable type that can be as wide
62 * as long, but also double or half...
64 static int num_bits_ulong(unsigned long value)
67 unsigned long ret = 0;
70 * It is argued that *on average* constant counter loop performs
71 * not worse [if not better] than one with conditional break or
72 * mask-n-table-lookup-style, because of branch misprediction
75 for (i = 0; i < sizeof(value) * 8; i++) {
83 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
87 unsigned long utmp, sign;
89 /* this exists to bypass broken gcc optimization */
90 char *cp = (char *)pval;
92 /* use memcpy, because we may not be long aligned */
93 memcpy(<mp, cp, sizeof(long));
98 * Convert the long to positive: we subtract one if negative so we can
99 * cleanly handle the padding if only the MSB of the leading octet is
104 utmp = 0 - (unsigned long)ltmp - 1;
109 clen = num_bits_ulong(utmp);
110 /* If MSB of leading octet set we need to pad */
116 /* Convert number of bits to number of octets */
117 clen = (clen + 7) >> 3;
121 *cont++ = (unsigned char)sign;
122 for (i = clen - 1; i >= 0; i--) {
123 cont[i] = (unsigned char)(utmp ^ sign);
130 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
131 int utype, char *free_cont, const ASN1_ITEM *it)
135 unsigned long utmp = 0, sign = 0x100;
136 char *cp = (char *)pval;
140 * Check possible pad byte. Worst case, we're skipping past actual
141 * content, but since that's only with 0x00 and 0xff and we set neg
142 * accordingly, the result will be correct in the end anyway.
157 if (len > (int)sizeof(long)) {
158 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
163 /* Is it negative? */
164 if (len && (cont[0] & 0x80))
168 } else if (((sign ^ cont[0]) & 0x80) == 0) { /* same sign bit? */
169 ASN1err(ASN1_F_LONG_C2I, ASN1_R_ILLEGAL_PADDING);
173 for (i = 0; i < len; i++) {
175 utmp |= cont[i] ^ sign;
179 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
184 if (ltmp == it->size) {
185 ASN1err(ASN1_F_LONG_C2I, ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
188 memcpy(cp, <mp, sizeof(long));
192 static int long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
193 int indent, const ASN1_PCTX *pctx)
195 return BIO_printf(out, "%ld\n", *(long *)pval);