1 /* crypto/asn1/a_int.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
61 #include <openssl/asn1.h>
63 ASN1_INTEGER *ASN1_INTEGER_dup(ASN1_INTEGER *x)
64 { return M_ASN1_INTEGER_dup(x);}
66 int ASN1_INTEGER_cmp(ASN1_INTEGER *x, ASN1_INTEGER *y)
67 { return M_ASN1_INTEGER_cmp(x,y);}
70 * This converts an ASN1 INTEGER into its content encoding.
71 * The internal representation is an ASN1_STRING whose data is a big endian
72 * representation of the value, ignoring the sign. The sign is determined by
73 * the type: V_ASN1_INTEGER for positive and V_ASN1_NEG_INTEGER for negative.
75 * Positive integers are no problem: they are almost the same as the DER
76 * encoding, except if the first byte is >= 0x80 we need to add a zero pad.
78 * Negative integers are a bit trickier...
79 * The DER representation of negative integers is in 2s complement form.
80 * The internal form is converted by complementing each octet and finally
81 * adding one to the result. This can be done less messily with a little trick.
82 * If the internal form has trailing zeroes then they will become FF by the
83 * complement and 0 by the add one (due to carry) so just copy as many trailing
84 * zeros to the destination as there are in the source. The carry will add one
85 * to the last none zero octet: so complement this octet and add one and finally
86 * complement any left over until you get to the start of the string.
88 * Padding is a little trickier too. If the first bytes is > 0x80 then we pad
89 * with 0xff. However if the first byte is 0x80 and one of the following bytes
90 * is non-zero we pad with 0xff. The reason for this distinction is that 0x80
91 * followed by optional zeros isn't padded.
94 int i2c_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **pp)
97 unsigned char *p,*n,pb=0;
99 if ((a == NULL) || (a->data == NULL)) return(0);
100 neg=a->type & V_ASN1_NEG;
107 if (!neg && (i > 127)) {
114 } else if(i == 128) {
116 * Special case: if any other bytes non zero we pad:
117 * otherwise we don't.
119 for(i = 1; i < a->length; i++) if(a->data[i]) {
128 if (pp == NULL) return(ret);
132 if (a->length == 0) *(p++)=0;
133 else if (!neg) memcpy(p,a->data,(unsigned int)a->length);
135 /* Begin at the end of the encoding */
136 n=a->data + a->length - 1;
139 /* Copy zeros to destination as long as source is zero */
145 /* Complement and increment next octet */
146 *(p--) = ((*(n--)) ^ 0xff) + 1;
148 /* Complement any octets left */
149 for(;i > 0; i--) *(p--) = *(n--) ^ 0xff;
156 /* Convert just ASN1 INTEGER content octets to ASN1_INTEGER structure */
158 ASN1_INTEGER *c2i_ASN1_INTEGER(ASN1_INTEGER **a, unsigned char **pp,
161 ASN1_INTEGER *ret=NULL;
162 unsigned char *p,*to,*s, *pend;
165 if ((a == NULL) || ((*a) == NULL))
167 if ((ret=M_ASN1_INTEGER_new()) == NULL) return(NULL);
168 ret->type=V_ASN1_INTEGER;
176 /* We must OPENSSL_malloc stuff, even for 0 bytes otherwise it
177 * signifies a missing NULL parameter. */
178 s=(unsigned char *)OPENSSL_malloc((int)len+1);
181 i=ERR_R_MALLOC_FAILURE;
186 /* Strictly speaking this is an illegal INTEGER but we
189 ret->type=V_ASN1_INTEGER;
190 } else if (*p & 0x80) /* a negative number */
192 ret->type=V_ASN1_NEG_INTEGER;
193 if ((*p == 0xff) && (len != 1)) {
205 /* Special case: if all zeros then the number will be of
206 * the form FF followed by n zero bytes: this corresponds to
207 * 1 followed by n zero bytes. We've already written n zeros
208 * so we just append an extra one and set the first byte to
209 * a 1. This is treated separately because it is the only case
210 * where the number of bytes is larger than len.
217 *(to--) = (*(p--) ^ 0xff) + 1;
219 for(;i > 0; i--) *(to--) = *(p--) ^ 0xff;
222 ret->type=V_ASN1_INTEGER;
223 if ((*p == 0) && (len != 1))
228 memcpy(s,p,(int)len);
231 if (ret->data != NULL) OPENSSL_free(ret->data);
233 ret->length=(int)len;
234 if (a != NULL) (*a)=ret;
238 ASN1err(ASN1_F_D2I_ASN1_INTEGER,i);
239 if ((ret != NULL) && ((a == NULL) || (*a != ret)))
240 M_ASN1_INTEGER_free(ret);
245 /* This is a version of d2i_ASN1_INTEGER that ignores the sign bit of
246 * ASN1 integers: some broken software can encode a positive INTEGER
247 * with its MSB set as negative (it doesn't add a padding zero).
250 ASN1_INTEGER *d2i_ASN1_UINTEGER(ASN1_INTEGER **a, unsigned char **pp,
253 ASN1_INTEGER *ret=NULL;
254 unsigned char *p,*to,*s;
259 if ((a == NULL) || ((*a) == NULL))
261 if ((ret=M_ASN1_INTEGER_new()) == NULL) return(NULL);
262 ret->type=V_ASN1_INTEGER;
268 inf=ASN1_get_object(&p,&len,&tag,&xclass,length);
271 i=ASN1_R_BAD_OBJECT_HEADER;
275 if (tag != V_ASN1_INTEGER)
277 i=ASN1_R_EXPECTING_AN_INTEGER;
281 /* We must OPENSSL_malloc stuff, even for 0 bytes otherwise it
282 * signifies a missing NULL parameter. */
283 s=(unsigned char *)OPENSSL_malloc((int)len+1);
286 i=ERR_R_MALLOC_FAILURE;
290 ret->type=V_ASN1_INTEGER;
292 if ((*p == 0) && (len != 1))
297 memcpy(s,p,(int)len);
301 if (ret->data != NULL) OPENSSL_free(ret->data);
303 ret->length=(int)len;
304 if (a != NULL) (*a)=ret;
308 ASN1err(ASN1_F_D2I_ASN1_UINTEGER,i);
309 if ((ret != NULL) && ((a == NULL) || (*a != ret)))
310 M_ASN1_INTEGER_free(ret);
314 int ASN1_INTEGER_set(ASN1_INTEGER *a, long v)
317 unsigned char buf[sizeof(long)+1];
320 a->type=V_ASN1_INTEGER;
321 if (a->length < (sizeof(long)+1))
324 OPENSSL_free(a->data);
325 if ((a->data=(unsigned char *)OPENSSL_malloc(sizeof(long)+1)) != NULL)
326 memset((char *)a->data,0,sizeof(long)+1);
330 ASN1err(ASN1_F_ASN1_INTEGER_SET,ERR_R_MALLOC_FAILURE);
337 a->type=V_ASN1_NEG_INTEGER;
340 for (i=0; i<sizeof(long); i++)
347 for (k=i-1; k >=0; k--)
353 long ASN1_INTEGER_get(ASN1_INTEGER *a)
358 if (a == NULL) return(0L);
360 if (i == V_ASN1_NEG_INTEGER)
362 else if (i != V_ASN1_INTEGER)
365 if (a->length > sizeof(long))
367 /* hmm... a bit ugly */
373 for (i=0; i<a->length; i++)
376 r|=(unsigned char)a->data[i];
382 ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai)
388 ret=M_ASN1_INTEGER_new();
393 ASN1err(ASN1_F_BN_TO_ASN1_INTEGER,ERR_R_NESTED_ASN1_ERROR);
396 if(bn->neg) ret->type = V_ASN1_NEG_INTEGER;
397 else ret->type=V_ASN1_INTEGER;
399 len=((j == 0)?0:((j/8)+1));
400 ret->data=(unsigned char *)OPENSSL_malloc(len+4);
401 ret->length=BN_bn2bin(bn,ret->data);
404 if (ret != ai) M_ASN1_INTEGER_free(ret);
408 BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai, BIGNUM *bn)
412 if ((ret=BN_bin2bn(ai->data,ai->length,bn)) == NULL)
413 ASN1err(ASN1_F_ASN1_INTEGER_TO_BN,ASN1_R_BN_LIB);
414 else if(ai->type == V_ASN1_NEG_INTEGER) ret->neg = 1;
418 IMPLEMENT_STACK_OF(ASN1_INTEGER)
419 IMPLEMENT_ASN1_SET_OF(ASN1_INTEGER)