static unsigned char asn1_ulong_decode(struct asn1_ctx *ctx,
unsigned char *eoc,
unsigned long *integer)
{
unsigned char ch;
unsigned int len;
if (!asn1_octet_decode(ctx, &ch))
return 0;
*integer = ch;
if (ch == 0) len = 0;
else len = 1;
while (ctx->pointer < eoc) {
if (++len > sizeof (unsigned long)) {
ctx->error = ASN1_ERR_DEC_BADVALUE;
return 0;
}
if (!asn1_octet_decode(ctx, &ch))
return 0;
*integer <<= 8;
*integer |= ch;
}
return 1;
}
static unsigned char asn1_length_decode(struct asn1_ctx *ctx,
unsigned int *def,
unsigned int *len)
{
unsigned char ch, cnt;
if (!asn1_octet_decode(ctx, &ch))
return 0;
if (ch == 0x80)
*def = 0;
else {
*def = 1;
if (ch < 0x80)
*len = ch;
else {
cnt = (unsigned char) (ch & 0x7F);
*len = 0;
while (cnt > 0) {
if (!asn1_octet_decode(ctx, &ch))
return 0;
*len <<= 8;
*len |= ch;
cnt--;
}
}
}
return 1;
}
static unsigned char asn1_eoc_decode(struct asn1_ctx *ctx, unsigned char *eoc)
{
unsigned char ch;
if (eoc == NULL) {
if (!asn1_octet_decode(ctx, &ch))
return 0;
if (ch != 0x00) {
ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
return 0;
}
if (!asn1_octet_decode(ctx, &ch))
return 0;
if (ch != 0x00) {
ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
return 0;
}
return 1;
} else {
if (ctx->pointer != eoc) {
ctx->error = ASN1_ERR_DEC_LENGTH_MISMATCH;
return 0;
}
return 1;
}
}
static unsigned char
asn1_length_decode(struct asn1_ctx *ctx, unsigned int *def, unsigned int *len)
{
unsigned char ch, cnt;
if (!asn1_octet_decode(ctx, &ch))
return 0;
if (ch == 0x80)
*def = 0;
else {
*def = 1;
if (ch < 0x80)
*len = ch;
else {
cnt = (unsigned char) (ch & 0x7F);
*len = 0;
while (cnt > 0) {
if (!asn1_octet_decode(ctx, &ch))
return 0;
*len <<= 8;
*len |= ch;
cnt--;
}
}
}
/* don't trust len bigger than ctx buffer */
if (*len > ctx->end - ctx->pointer)
return 0;
return 1;
}
static unsigned char asn1_octets_decode(struct asn1_ctx *ctx,
unsigned char *eoc,
unsigned char **octets,
unsigned int *len)
{
unsigned char *ptr;
*len = 0;
*octets = kmalloc((eoc - ctx->pointer), GFP_ATOMIC);
if (*octets == NULL) {
if (net_ratelimit())
pr_notice("OOM in bsalg (%d)\n", __LINE__);
return 0;
}
ptr = *octets;
while (ctx->pointer < eoc) {
if (!asn1_octet_decode(ctx, (unsigned char *)ptr++)) {
kfree(*octets);
*octets = NULL;
return 0;
}
(*len)++;
}
return 1;
}
static unsigned char asn1_tag_decode(struct asn1_ctx *ctx, unsigned int *tag)
{
unsigned char ch;
*tag = 0;
do
{
if (!asn1_octet_decode(ctx, &ch))
return 0;
*tag <<= 7;
*tag |= ch & 0x7F;
} while ((ch & 0x80) == 0x80);
return 1;
}
/*
* NAME: asn1_tag_get
* SYNOPSIS: int asn1_tag_get
* (
* ASN1_SCK *asn1,
* guint *tag
* )
* DESCRIPTION: Decodes a tag number, combining it with existing tag bits.
* RETURNS: ASN1_ERR value (ASN1_ERR_NOERROR on success)
*/
static int
asn1_tag_get(ASN1_SCK *asn1, guint *tag)
{
int ret;
guchar ch;
do {
ret = asn1_octet_decode (asn1, &ch);
if (ret != ASN1_ERR_NOERROR)
return ret;
*tag <<= 7;
*tag |= ch & 0x7F;
} while ((ch & 0x80) == 0x80);
return ASN1_ERR_NOERROR;
}
static unsigned char asn1_subid_decode(struct asn1_ctx *ctx,
unsigned long *subid)
{
unsigned char ch;
*subid = 0;
do {
if (!asn1_octet_decode(ctx, &ch))
return 0;
*subid <<= 7;
*subid |= ch & 0x7F;
} while ((ch & 0x80) == 0x80);
return 1;
}
/*
* NAME: asn1_id_decode1
* SYNOPSIS: int asn1_id_decode1
* (
* ASN1_SCK *asn1,
* guint *tag
* )
* DESCRIPTION: Decodes an identifier.
* Like asn1_id_decode() except that the Class and Constructor
* bits are returned in the tag.
* RETURNS: ASN1_ERR value (ASN1_ERR_NOERROR on success)
*/
int
asn1_id_decode1(ASN1_SCK *asn1, guint *tag)
{
int ret;
guchar ch;
*tag = 0;
ret = asn1_octet_decode (asn1, &ch);
if (ret != ASN1_ERR_NOERROR)
return ret;
*tag = ch;
if ((*tag & 0x1F) == 0x1F) { /* high-tag-number format */
*tag = ch >> 5; /* leave just the Class and Constructor bits */
ret = asn1_tag_get (asn1, tag);
if (ret != ASN1_ERR_NOERROR)
return ret;
}
static unsigned char
asn1_id_decode(struct asn1_ctx *ctx,
unsigned int *cls, unsigned int *con, unsigned int *tag)
{
unsigned char ch;
if (!asn1_octet_decode(ctx, &ch))
return 0;
*cls = (ch & 0xC0) >> 6;
*con = (ch & 0x20) >> 5;
*tag = (ch & 0x1F);
if (*tag == 0x1F) {
if (!asn1_tag_decode(ctx, tag))
return 0;
}
return 1;
}
/*
* NAME: asn1_id_decode
* SYNOPSIS: int asn1_id_decode
* (
* ASN1_SCK *asn1,
* guint *cls,
* guint *con,
* guint *tag
* )
* DESCRIPTION: Decodes an identifier.
* RETURNS: ASN1_ERR value (ASN1_ERR_NOERROR on success)
*/
int
asn1_id_decode(ASN1_SCK *asn1, guint *cls, guint *con, guint *tag)
{
int ret;
guchar ch;
*tag = 0;
ret = asn1_octet_decode (asn1, &ch);
if (ret != ASN1_ERR_NOERROR)
return ret;
*cls = (ch & 0xC0) >> 6;
*con = (ch & 0x20) >> 5;
*tag = (ch & 0x1F);
if (*tag == 0x1F) {
ret = asn1_tag_decode (asn1, tag);
if (ret != ASN1_ERR_NOERROR)
return ret;
}
return ASN1_ERR_NOERROR;
}
static unsigned char asn1_octets_decode(struct asn1_ctx *ctx,
unsigned char *eoc,
unsigned char **octets,
unsigned int *len)
{
unsigned char *ptr;
*len = 0;
*octets = kmalloc(eoc - ctx->pointer, GFP_ATOMIC);
if (*octets == NULL)
return 0;
ptr = *octets;
while (ctx->pointer < eoc) {
if (!asn1_octet_decode(ctx, (unsigned char *)ptr++)) {
kfree(*octets);
*octets = NULL;
return 0;
}
(*len)++;
}
return 1;
}
