1 /* $OpenBSD: x_long.c,v 1.16 2019/04/20 11:13:15 jsing Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 #include <stdio.h>
60 #include <string.h>
61 
62 #include <openssl/asn1t.h>
63 #include <openssl/bn.h>
64 #include <openssl/err.h>
65 
66 /*
67  * Custom primitive type for long handling. This converts between an
68  * ASN1_INTEGER and a long directly.
69  */
70 
71 static int long_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
72 static void long_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
73 
74 static int long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
75     const ASN1_ITEM *it);
76 static int long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
77     int utype, char *free_cont, const ASN1_ITEM *it);
78 static int long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
79     int indent, const ASN1_PCTX *pctx);
80 
81 static ASN1_PRIMITIVE_FUNCS long_pf = {
82 	.app_data = NULL,
83 	.flags = 0,
84 	.prim_new = long_new,
85 	.prim_free = long_free,
86 	.prim_clear = long_free,	/* Clear should set to initial value */
87 	.prim_c2i = long_c2i,
88 	.prim_i2c = long_i2c,
89 	.prim_print = long_print,
90 };
91 
92 const ASN1_ITEM LONG_it = {
93 	.itype = ASN1_ITYPE_PRIMITIVE,
94 	.utype = V_ASN1_INTEGER,
95 	.templates = NULL,
96 	.tcount = 0,
97 	.funcs = &long_pf,
98 	.size = ASN1_LONG_UNDEF,
99 	.sname = "LONG",
100 };
101 
102 const ASN1_ITEM ZLONG_it = {
103 	.itype = ASN1_ITYPE_PRIMITIVE,
104 	.utype = V_ASN1_INTEGER,
105 	.templates = NULL,
106 	.tcount = 0,
107 	.funcs = &long_pf,
108 	.size = 0,
109 	.sname = "ZLONG",
110 };
111 
112 static int
long_new(ASN1_VALUE ** pval,const ASN1_ITEM * it)113 long_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
114 {
115 	*(long *)pval = it->size;
116 	return 1;
117 }
118 
119 static void
long_free(ASN1_VALUE ** pval,const ASN1_ITEM * it)120 long_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
121 {
122 	*(long *)pval = it->size;
123 }
124 
125 static int
long_i2c(ASN1_VALUE ** pval,unsigned char * cont,int * putype,const ASN1_ITEM * it)126 long_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
127     const ASN1_ITEM *it)
128 {
129 	long ltmp;
130 	unsigned long utmp;
131 	int clen, pad, i;
132 	/* this exists to bypass broken gcc optimization */
133 	char *cp = (char *)pval;
134 
135 	/* use memcpy, because we may not be long aligned */
136 	memcpy(&ltmp, cp, sizeof(long));
137 
138 	if (ltmp == it->size)
139 		return -1;
140 	/* Convert the long to positive: we subtract one if negative so
141 	 * we can cleanly handle the padding if only the MSB of the leading
142 	 * octet is set.
143 	 */
144 	if (ltmp < 0)
145 		utmp = -(ltmp + 1);
146 	else
147 		utmp = ltmp;
148 	clen = BN_num_bits_word(utmp);
149 	/* If MSB of leading octet set we need to pad */
150 	if (!(clen & 0x7))
151 		pad = 1;
152 	else
153 		pad = 0;
154 
155 	/* Convert number of bits to number of octets */
156 	clen = (clen + 7) >> 3;
157 
158 	if (cont) {
159 		if (pad)
160 			*cont++ = (ltmp < 0) ? 0xff : 0;
161 		for (i = clen - 1; i >= 0; i--) {
162 			cont[i] = (unsigned char)(utmp & 0xff);
163 			if (ltmp < 0)
164 				cont[i] ^= 0xff;
165 			utmp >>= 8;
166 		}
167 	}
168 	return clen + pad;
169 }
170 
171 static int
long_c2i(ASN1_VALUE ** pval,const unsigned char * cont,int len,int utype,char * free_cont,const ASN1_ITEM * it)172 long_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, int utype,
173     char *free_cont, const ASN1_ITEM *it)
174 {
175 	int neg, i;
176 	long ltmp;
177 	unsigned long utmp = 0;
178 	char *cp = (char *)pval;
179 	if (len > (int)sizeof(long)) {
180 		ASN1error(ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
181 		return 0;
182 	}
183 	/* Is it negative? */
184 	if (len && (cont[0] & 0x80))
185 		neg = 1;
186 	else
187 		neg = 0;
188 	utmp = 0;
189 	for (i = 0; i < len; i++) {
190 		utmp <<= 8;
191 		if (neg)
192 			utmp |= cont[i] ^ 0xff;
193 		else
194 			utmp |= cont[i];
195 	}
196 	ltmp = (long)utmp;
197 	if (neg) {
198 		ltmp = -ltmp;
199 		ltmp--;
200 	}
201 	if (ltmp == it->size) {
202 		ASN1error(ASN1_R_INTEGER_TOO_LARGE_FOR_LONG);
203 		return 0;
204 	}
205 	memcpy(cp, &ltmp, sizeof(long));
206 	return 1;
207 }
208 
209 static int
long_print(BIO * out,ASN1_VALUE ** pval,const ASN1_ITEM * it,int indent,const ASN1_PCTX * pctx)210 long_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it, int indent,
211     const ASN1_PCTX *pctx)
212 {
213 	if (BIO_printf(out, "%ld\n", *(long *)pval) <= 0)
214 		return 0;
215 
216 	return 1;
217 }
218