giomba
/
opensc
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

sc_asn1_decode_integer/asn1_encode_integer: correctly manage negative 

numbers and some positive numbers like 128


git-svn-id: https://www.opensc-project.org/svnp/opensc/trunk@3401 c6295689-39f2-0310-b995-f0e70906c6a9
This commit is contained in:
ludovic.rousseau 2008-02-29 15:37:46 +00:00
parent 04942bb4f6
commit 9740726f16
1 changed files with 39 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
src/libopensc/asn1.c
View File

@ -533,6 +533,8 @@ int sc_asn1_decode_integer(const u8 * inbuf, size_t inlen, int *out)
if (inlen > sizeof(int))
return SC_ERROR_INVALID_ASN1_OBJECT;
if (inbuf[0] & 0x80)
a = -1;
for (i = 0; i < inlen; i++) {
a <<= 8;
a |= *inbuf++;
@ -543,20 +545,53 @@ int sc_asn1_decode_integer(const u8 * inbuf, size_t inlen, int *out)
static int asn1_encode_integer(int in, u8 ** obj, size_t * objsize)
{
int i = sizeof(in) * 8, skip = 1;
int i = sizeof(in) * 8, skip_zero, skip_sign;
u8 *p, b;
*obj = p = (u8 *) malloc(sizeof(in));
if (in < 0)
{
skip_sign = 1;
skip_zero= 0;
}
else
{
skip_sign = 0;
skip_zero= 1;
}
*obj = p = (u8 *) malloc(sizeof(in)+1);
if (*obj == NULL)
return SC_ERROR_OUT_OF_MEMORY;
do {
i -= 8;
b = in >> i;
if (b == 0 && skip)
if (skip_sign)
{
if (b != 0xff)
skip_sign = 0;
if (b & 0x80)
{
*p = b;
if (0xff == b)
continue;
}
else
{
p++;
skip_sign = 0;
}
}
if (b == 0 && skip_zero)
continue;
skip = 0;
if (skip_zero) {
skip_zero = 0;
/* prepend 0x00 if MSb is 1 and integer positive */
if ((b & 0x80) != 0 && in > 0)
*p++ = 0;
}
*p++ = b;
} while (i > 0);
if (skip_sign)
p++;
*objsize = p - *obj;
if (*objsize == 0) {
*objsize = 1;