/**
Decode a CHOICE
@param in The DER encoded input
@param inlen [in/out] The size of the input and resulting size of read type
@param list The list of items to decode
@param outlen The number of items in the list
@return CRYPT_OK on success
*/
int der_decode_choice(const unsigned char *in, unsigned long *inlen,
ltc_asn1_list *list, unsigned long outlen)
{
unsigned long size, x, z;
void *data;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(inlen != NULL);
LTC_ARGCHK(list != NULL);
/* get blk size */
if (*inlen < 2) {
return CRYPT_INVALID_PACKET;
}
/* set all of the "used" flags to zero */
for (x = 0; x < outlen; x++) {
list[x].used = 0;
}
/* now scan until we have a winner */
for (x = 0; x < outlen; x++) {
size = list[x].size;
data = list[x].data;
switch (list[x].type) {
case LTC_ASN1_BOOLEAN:
if (der_decode_boolean(in, *inlen, data) == CRYPT_OK) {
if (der_length_boolean(&z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_INTEGER:
if (der_decode_integer(in, *inlen, data) == CRYPT_OK) {
if (der_length_integer(data, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_SHORT_INTEGER:
if (der_decode_short_integer(in, *inlen, data) == CRYPT_OK) {
if (der_length_short_integer(size, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_BIT_STRING:
if (der_decode_bit_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_bit_string(size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_RAW_BIT_STRING:
if (der_decode_raw_bit_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_bit_string(size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_OCTET_STRING:
if (der_decode_octet_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_octet_string(size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_NULL:
if (*inlen == 2 && in[x] == 0x05 && in[x+1] == 0x00) {
*inlen = 2;
list[x].used = 1;
return CRYPT_OK;
}
break;
case LTC_ASN1_OBJECT_IDENTIFIER:
if (der_decode_object_identifier(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_object_identifier(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_TELETEX_STRING:
if (der_decode_teletex_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_teletex_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_IA5_STRING:
if (der_decode_ia5_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_ia5_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_PRINTABLE_STRING:
if (der_decode_printable_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_printable_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_UTF8_STRING:
if (der_decode_utf8_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_utf8_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_UTCTIME:
z = *inlen;
if (der_decode_utctime(in, &z, data) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
break;
case LTC_ASN1_GENERALIZEDTIME:
z = *inlen;
if (der_decode_generalizedtime(in, &z, data) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
break;
case LTC_ASN1_SET:
case LTC_ASN1_SETOF:
case LTC_ASN1_SEQUENCE:
if (der_decode_sequence(in, *inlen, data, size) == CRYPT_OK) {
if (der_length_sequence(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_CUSTOM_TYPE:
if (der_decode_custom_type(in, *inlen, &list[x]) == CRYPT_OK) {
if (der_length_custom_type(&list[x], &z, NULL) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_CHOICE:
case LTC_ASN1_EOL:
return CRYPT_INVALID_ARG;
}
}
return CRYPT_INVALID_PACKET;
}
/**
Extended-decode a Custom type
This function is used to decode custom types and sequences/sets
For custom types root is used
For sequences/sets list and outlen are used
@param in The DER encoded input
@param inlen The size of the input
@param root The item that defines the custom type to decode
@param list The list of items to decode
@param outlen The number of items in the list
@param flags c.f. enum ltc_der_seq
@return CRYPT_OK on success
*/
int der_decode_custom_type_ex(const unsigned char *in, unsigned long inlen,
ltc_asn1_list *root,
ltc_asn1_list *list, unsigned long outlen,
unsigned int flags)
{
int err, seq_err, i, ordered;
ltc_asn1_type type;
ltc_asn1_list ident;
unsigned long size, x, y, z, blksize;
unsigned char* in_new = NULL;
void *data;
LTC_ARGCHK(in != NULL);
/* get blk size */
if (inlen < 2) {
return CRYPT_INVALID_PACKET;
}
x = 0;
if (root == NULL) {
LTC_ARGCHK(list != NULL);
/* sequence type? We allow 0x30 SEQUENCE and 0x31 SET since fundamentally they're the same structure */
if (in[x] != 0x30 && in[x] != 0x31) {
return CRYPT_INVALID_PACKET;
}
++x;
} else {
if (root->type != LTC_ASN1_CUSTOM_TYPE) {
return CRYPT_INVALID_PACKET;
}
/* Alloc a copy of the data for primitive handling. */
if (root->pc == LTC_ASN1_PC_PRIMITIVE) {
in_new = XMALLOC(inlen);
if (in_new == NULL) {
return CRYPT_MEM;
}
XMEMCPY(in_new, in, inlen);
in = in_new;
}
y = inlen;
if ((err = der_decode_asn1_identifier(in, &y, &ident)) != CRYPT_OK) {
goto LBL_ERR;
}
if ((ident.type != root->type) ||
(ident.klass != root->klass) ||
(ident.pc != root->pc) ||
(ident.tag != root->tag)) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
x += y;
list = root->data;
outlen = root->size;
}
if (root != NULL && root->pc == LTC_ASN1_PC_PRIMITIVE) {
if (((unsigned long)root->used >= der_asn1_type_to_identifier_map_sz) ||
(der_asn1_type_to_identifier_map[root->used] == -1)) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
root->type = (ltc_asn1_type)root->used;
list = root;
outlen = 1;
x -= 1;
in_new[x] = (unsigned char)der_asn1_type_to_identifier_map[list[0].type];
blksize = inlen - x;
} else {
y = inlen - x;
if ((err = der_decode_asn1_length(&in[x], &y, &blksize)) != CRYPT_OK) {
goto LBL_ERR;
}
x += y;
}
/* would this blksize overflow? */
if (blksize > (inlen - x)) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
/* mark all as unused */
for (i = 0; i < (int)outlen; i++) {
list[i].used = 0;
}
ordered = flags & LTC_DER_SEQ_ORDERED;
/* ok read data */
seq_err = CRYPT_OK;
blksize += x;
inlen -= x;
for (i = 0; i < (int)outlen; i++) {
z = 0;
type = list[i].type;
size = list[i].size;
data = list[i].data;
if (!ordered && list[i].used == 1) { continue; }
if (type == LTC_ASN1_EOL) {
break;
}
if (root != NULL && root->pc == LTC_ASN1_PC_PRIMITIVE && i != 0) {
err = CRYPT_PK_ASN1_ERROR;
goto LBL_ERR;
}
switch (type) {
case LTC_ASN1_BOOLEAN:
z = inlen;
if ((err = der_decode_boolean(in + x, z, ((int *)data))) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_boolean(&z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_INTEGER:
z = inlen;
if ((err = der_decode_integer(in + x, z, data)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_integer(data, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_SHORT_INTEGER:
z = inlen;
if ((err = der_decode_short_integer(in + x, z, data)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_short_integer(((unsigned long*)data)[0], &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_BIT_STRING:
z = inlen;
if ((err = der_decode_bit_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_bit_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_RAW_BIT_STRING:
z = inlen;
if ((err = der_decode_raw_bit_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_bit_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_OCTET_STRING:
z = inlen;
if ((err = der_decode_octet_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_octet_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_NULL:
if (inlen < 2 || in[x] != 0x05 || in[x+1] != 0x00) {
if (!ordered || list[i].optional) { continue; }
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
z = 2;
break;
case LTC_ASN1_OBJECT_IDENTIFIER:
z = inlen;
if ((err = der_decode_object_identifier(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_object_identifier(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_TELETEX_STRING:
z = inlen;
if ((err = der_decode_teletex_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_teletex_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_IA5_STRING:
z = inlen;
if ((err = der_decode_ia5_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_ia5_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_PRINTABLE_STRING:
z = inlen;
if ((err = der_decode_printable_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_printable_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_UTF8_STRING:
z = inlen;
if ((err = der_decode_utf8_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_utf8_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_UTCTIME:
z = inlen;
if ((err = der_decode_utctime(in + x, &z, data)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_GENERALIZEDTIME:
z = inlen;
if ((err = der_decode_generalizedtime(in + x, &z, data)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_SET:
z = inlen;
if ((err = der_decode_set(in + x, z, data, size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_sequence(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_SETOF:
case LTC_ASN1_SEQUENCE:
/* detect if we have the right type */
if ((type == LTC_ASN1_SETOF && (in[x] & 0x3F) != 0x31) || (type == LTC_ASN1_SEQUENCE && (in[x] & 0x3F) != 0x30)) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
z = inlen;
err = der_decode_sequence_ex(in + x, z, data, size, flags);
if (err == CRYPT_INPUT_TOO_LONG) {
seq_err = CRYPT_INPUT_TOO_LONG;
err = CRYPT_OK;
}
if (err != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_sequence(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_CUSTOM_TYPE:
z = inlen;
err = der_decode_custom_type(in + x, z, &list[i]);
if (err == CRYPT_INPUT_TOO_LONG) {
seq_err = CRYPT_INPUT_TOO_LONG;
err = CRYPT_OK;
}
if (err != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
if ((err = der_length_custom_type(&list[i], &z, NULL)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_CHOICE:
z = inlen;
if ((err = der_decode_choice(in + x, &z, data, size)) != CRYPT_OK) {
if (!ordered || list[i].optional) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_EOL:
err = CRYPT_INVALID_ARG;
goto LBL_ERR;
}
x += z;
inlen -= z;
list[i].used = 1;
if (!ordered) {
/* restart the decoder */
i = -1;
}
}
for (i = 0; i < (int)outlen; i++) {
if (list[i].used == 0 && list[i].optional == 0) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
}
if (blksize == x && seq_err == CRYPT_OK && inlen == 0) {
/* everything decoded and no errors in nested sequences */
err = CRYPT_OK;
} else if (blksize == x && seq_err == CRYPT_INPUT_TOO_LONG && inlen == 0) {
/* a sequence reported too-long input, but now we've decoded everything */
err = CRYPT_OK;
} else if (blksize != x && ((flags & LTC_DER_SEQ_STRICT) == LTC_DER_SEQ_STRICT)) {
err = CRYPT_INVALID_PACKET;
} else {
err = CRYPT_INPUT_TOO_LONG;
}
LBL_ERR:
if (in_new != NULL) {
XFREE(in_new);
}
return err;
}
/**
ASN.1 DER Flexi(ble) decoder will decode arbitrary DER packets and create a linked list of the decoded elements.
@param in The input buffer
@param inlen [in/out] The length of the input buffer and on output the amount of decoded data
@param out [out] A pointer to the linked list
@return CRYPT_OK on success.
*/
int der_decode_sequence_flexi(const unsigned char *in, unsigned long *inlen, ltc_asn1_list **out)
{
ltc_asn1_list *l;
unsigned long err, type, len, totlen, data_offset;
void *realloc_tmp;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(inlen != NULL);
LTC_ARGCHK(out != NULL);
l = NULL;
totlen = 0;
/* scan the input and and get lengths and what not */
while (*inlen) {
/* read the type byte */
type = *in;
/* fetch length */
len = fetch_length(in, *inlen, &data_offset);
if (len > *inlen) {
err = CRYPT_INVALID_PACKET;
goto error;
}
/* alloc new link */
if (l == NULL) {
l = XCALLOC(1, sizeof(*l));
if (l == NULL) {
err = CRYPT_MEM;
goto error;
}
} else {
l->next = XCALLOC(1, sizeof(*l));
if (l->next == NULL) {
err = CRYPT_MEM;
goto error;
}
l->next->prev = l;
l = l->next;
}
if ((type & 0x20) && (type != 0x30) && (type != 0x31)) {
/* constructed, use the 'used' field to store the original identifier */
l->used = type;
/* treat constructed elements like SETs */
type = 0x20;
}
else if ((type & 0xC0) == 0x80) {
/* context-specific, use the 'used' field to store the original identifier */
l->used = type;
/* context-specific elements are treated as opaque data */
type = 0x80;
}
/* now switch on type */
switch (type) {
case 0x01: /* BOOLEAN */
l->type = LTC_ASN1_BOOLEAN;
l->size = 1;
l->data = XCALLOC(1, sizeof(int));
if ((err = der_decode_boolean(in, *inlen, l->data)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_boolean(&len)) != CRYPT_OK) {
goto error;
}
break;
case 0x02: /* INTEGER */
/* init field */
l->type = LTC_ASN1_INTEGER;
l->size = 1;
if ((err = mp_init(&l->data)) != CRYPT_OK) {
goto error;
}
/* decode field */
if ((err = der_decode_integer(in, *inlen, l->data)) != CRYPT_OK) {
goto error;
}
/* calc length of object */
if ((err = der_length_integer(l->data, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x03: /* BIT */
/* init field */
l->type = LTC_ASN1_BIT_STRING;
l->size = len * 8; /* *8 because we store decoded bits one per char and they are encoded 8 per char. */
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_bit_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_bit_string(l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x04: /* OCTET */
/* init field */
l->type = LTC_ASN1_OCTET_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_octet_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_octet_string(l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x05: /* NULL */
/* valid NULL is 0x05 0x00 */
if (in[0] != 0x05 || in[1] != 0x00) {
err = CRYPT_INVALID_PACKET;
goto error;
}
/* simple to store ;-) */
l->type = LTC_ASN1_NULL;
l->data = NULL;
l->size = 0;
len = 2;
break;
case 0x06: /* OID */
/* init field */
l->type = LTC_ASN1_OBJECT_IDENTIFIER;
l->size = len;
if ((l->data = XCALLOC(len, sizeof(unsigned long))) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_object_identifier(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_object_identifier(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
/* resize it to save a bunch of mem */
if ((realloc_tmp = XREALLOC(l->data, l->size * sizeof(unsigned long))) == NULL) {
/* out of heap but this is not an error */
break;
}
l->data = realloc_tmp;
break;
case 0x0C: /* UTF8 */
/* init field */
l->type = LTC_ASN1_UTF8_STRING;
l->size = len;
if ((l->data = XCALLOC(sizeof(wchar_t), l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_utf8_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_utf8_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x13: /* PRINTABLE */
/* init field */
l->type = LTC_ASN1_PRINTABLE_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_printable_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_printable_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x14: /* TELETEXT */
/* init field */
l->type = LTC_ASN1_TELETEX_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_teletex_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_teletex_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x16: /* IA5 */
/* init field */
l->type = LTC_ASN1_IA5_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_ia5_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_ia5_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x17: /* UTC TIME */
/* init field */
l->type = LTC_ASN1_UTCTIME;
l->size = 1;
if ((l->data = XCALLOC(1, sizeof(ltc_utctime))) == NULL) {
err = CRYPT_MEM;
goto error;
}
len = *inlen;
if ((err = der_decode_utctime(in, &len, l->data)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_utctime(l->data, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x20: /* Any CONSTRUCTED element that is neither SEQUENCE nor SET */
case 0x30: /* SEQUENCE */
case 0x31: /* SET */
/* init field */
if (type == 0x20) {
l->type = LTC_ASN1_CONSTRUCTED;
}
else if (type == 0x30) {
l->type = LTC_ASN1_SEQUENCE;
}
else {
l->type = LTC_ASN1_SET;
}
/* jump to the start of the data */
in += data_offset;
*inlen -= data_offset;
len = len - data_offset;
/* Sequence elements go as child */
if ((err = der_decode_sequence_flexi(in, &len, &(l->child))) != CRYPT_OK) {
goto error;
}
/* len update */
totlen += data_offset;
/* the flexi decoder can also do nothing, so make sure a child has been allocated */
if (l->child) {
/* link them up y0 */
l->child->parent = l;
}
break;
case 0x80: /* Context-specific */
l->type = LTC_ASN1_CONTEXT_SPECIFIC;
if ((l->data = XCALLOC(1, len - data_offset)) == NULL) {
err = CRYPT_MEM;
goto error;
}
XMEMCPY(l->data, in + data_offset, len - data_offset);
l->size = len - data_offset;
break;
default:
/* invalid byte ... this is a soft error */
/* remove link */
if (l->prev) {
l = l->prev;
XFREE(l->next);
l->next = NULL;
}
goto outside;
}
/* advance pointers */
totlen += len;
in += len;
*inlen -= len;
}
outside:
/* in case we processed anything */
if (totlen) {
/* rewind l please */
while (l->prev != NULL || l->parent != NULL) {
if (l->parent != NULL) {
l = l->parent;
} else {
l = l->prev;
}
}
}
/* return */
*out = l;
*inlen = totlen;
return CRYPT_OK;
error:
/* free list */
der_sequence_free(l);
return err;
}
/**
ASN.1 DER Flexi(ble) decoder will decode arbitrary DER packets and create a linked list of the decoded elements.
@param in The input buffer
@param inlen [in/out] The length of the input buffer and on output the amount of decoded data
@param out [out] A pointer to the linked list
@return CRYPT_OK on success.
*/
int der_decode_sequence_flexi(const unsigned char *in, unsigned long *inlen, ltc_asn1_list **out)
{
ltc_asn1_list *l;
unsigned long err, type, len, totlen, x, y;
void *realloc_tmp;
int isConstructed;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(inlen != NULL);
LTC_ARGCHK(out != NULL);
l = NULL;
totlen = 0;
/* scan the input and and get lengths and what not */
while (*inlen) {
/* read the type byte */
type = *in;
/* fetch length */
len = fetch_length(in, *inlen);
if (len > *inlen) {
err = CRYPT_INVALID_PACKET;
goto error;
}
/* alloc new link */
if (l == NULL) {
l = XCALLOC(1, sizeof(*l));
if (l == NULL) {
err = CRYPT_MEM;
goto error;
}
} else {
l->next = XCALLOC(1, sizeof(*l));
if (l->next == NULL) {
err = CRYPT_MEM;
goto error;
}
l->next->prev = l;
l = l->next;
}
if ((isConstructed = ((type & 0xE0) == 0xA0 ? 1 : 0))) {
/* constructed, use the 'used' field to store the original tag number */
l->used = (type & 0x1F);
/* treat constructed elements like SETs */
type = 0x31;
}
/* now switch on type */
switch (type) {
case 0x01: /* BOOLEAN */
l->type = LTC_ASN1_BOOLEAN;
l->size = 1;
l->data = XCALLOC(1, sizeof(int));
if ((err = der_decode_boolean(in, *inlen, l->data)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_boolean(&len)) != CRYPT_OK) {
goto error;
}
break;
case 0x02: /* INTEGER */
/* init field */
l->type = LTC_ASN1_INTEGER;
l->size = 1;
if ((err = mp_init(&l->data)) != CRYPT_OK) {
goto error;
}
/* decode field */
if ((err = der_decode_integer(in, *inlen, l->data)) != CRYPT_OK) {
goto error;
}
/* calc length of object */
if ((err = der_length_integer(l->data, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x03: /* BIT */
/* init field */
l->type = LTC_ASN1_BIT_STRING;
l->size = len * 8; /* *8 because we store decoded bits one per char and they are encoded 8 per char. */
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_bit_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_bit_string(l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x04: /* OCTET */
/* init field */
l->type = LTC_ASN1_OCTET_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_octet_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_octet_string(l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x05: /* NULL */
/* valid NULL is 0x05 0x00 */
if (in[0] != 0x05 || in[1] != 0x00) {
err = CRYPT_INVALID_PACKET;
goto error;
}
/* simple to store ;-) */
l->type = LTC_ASN1_NULL;
l->data = NULL;
l->size = 0;
len = 2;
break;
case 0x06: /* OID */
/* init field */
l->type = LTC_ASN1_OBJECT_IDENTIFIER;
l->size = len;
if ((l->data = XCALLOC(len, sizeof(unsigned long))) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_object_identifier(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_object_identifier(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
/* resize it to save a bunch of mem */
if ((realloc_tmp = XREALLOC(l->data, l->size * sizeof(unsigned long))) == NULL) {
/* out of heap but this is not an error */
break;
}
l->data = realloc_tmp;
break;
case 0x0C: /* UTF8 */
/* init field */
l->type = LTC_ASN1_UTF8_STRING;
l->size = len;
if ((l->data = XCALLOC(sizeof(wchar_t), l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_utf8_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_utf8_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x13: /* PRINTABLE */
/* init field */
l->type = LTC_ASN1_PRINTABLE_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_printable_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_printable_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x14: /* TELETEXT */
/* init field */
l->type = LTC_ASN1_TELETEX_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_teletex_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_teletex_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x16: /* IA5 */
/* init field */
l->type = LTC_ASN1_IA5_STRING;
l->size = len;
if ((l->data = XCALLOC(1, l->size)) == NULL) {
err = CRYPT_MEM;
goto error;
}
if ((err = der_decode_ia5_string(in, *inlen, l->data, &l->size)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_ia5_string(l->data, l->size, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x17: /* UTC TIME */
/* init field */
l->type = LTC_ASN1_UTCTIME;
l->size = 1;
if ((l->data = XCALLOC(1, sizeof(ltc_utctime))) == NULL) {
err = CRYPT_MEM;
goto error;
}
len = *inlen;
if ((err = der_decode_utctime(in, &len, l->data)) != CRYPT_OK) {
goto error;
}
if ((err = der_length_utctime(l->data, &len)) != CRYPT_OK) {
goto error;
}
break;
case 0x30: /* SEQUENCE */
case 0x31: /* SET */
/* init field */
l->type = (isConstructed ? LTC_ASN1_CONSTRUCTED : ((type == 0x30) ? LTC_ASN1_SEQUENCE : LTC_ASN1_SET));
/* we have to decode the SEQUENCE header and get it's length */
/* move past type */
++in; --(*inlen);
/* read length byte */
x = *in++; --(*inlen);
/* smallest SEQUENCE/SET header */
y = 2;
/* now if it's > 127 the next bytes are the length of the length */
if (x > 128) {
x &= 0x7F;
in += x;
*inlen -= x;
/* update sequence header len */
y += x;
}
/* Sequence elements go as child */
len = len - y;
if ((err = der_decode_sequence_flexi(in, &len, &(l->child))) != CRYPT_OK) {
goto error;
}
/* len update */
totlen += y;
/* link them up y0 */
l->child->parent = l;
break;
default:
/* invalid byte ... this is a soft error */
/* remove link */
if (l->prev) {
l = l->prev;
XFREE(l->next);
l->next = NULL;
}
goto outside;
}
/* advance pointers */
totlen += len;
in += len;
*inlen -= len;
}
outside:
/* rewind l please */
while (l->prev != NULL || l->parent != NULL) {
if (l->parent != NULL) {
l = l->parent;
} else {
l = l->prev;
}
}
/* return */
*out = l;
*inlen = totlen;
return CRYPT_OK;
error:
/* free list */
der_sequence_free(l);
return err;
}
/**
Decode a SEQUENCE
@param in The DER encoded input
@param inlen The size of the input
@param list The list of items to decode
@param outlen The number of items in the list
@param ordered Search an unordeded or ordered list
@return CRYPT_OK on success
*/
int der_decode_sequence_ex(const unsigned char *in, unsigned long inlen,
ltc_asn1_list *list, unsigned long outlen, int ordered)
{
int err, i;
ltc_asn1_type type;
unsigned long size, x, y, z, blksize;
void *data;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(list != NULL);
/* get blk size */
if (inlen < 2) {
return CRYPT_INVALID_PACKET;
}
/* sequence type? We allow 0x30 SEQUENCE and 0x31 SET since fundamentally they're the same structure */
x = 0;
if (in[x] != 0x30 && in[x] != 0x31) {
return CRYPT_INVALID_PACKET;
}
++x;
/* check if the msb is set, which signals that the
* 7 lsb bits represent the number of bytes of the length
*/
if (in[x] < 128) {
blksize = in[x++];
} else {
if (in[x] < 0x81 || in[x] > 0x83) {
return CRYPT_INVALID_PACKET;
}
y = in[x++] & 0x7F;
/* would reading the len bytes overrun? */
if (x + y > inlen) {
return CRYPT_INVALID_PACKET;
}
/* read len */
blksize = 0;
while (y--) {
blksize = (blksize << 8) | (unsigned long)in[x++];
}
}
/* would this blksize overflow? */
if (x + blksize > inlen) {
return CRYPT_INVALID_PACKET;
}
/* mark all as unused */
for (i = 0; i < (int)outlen; i++) {
list[i].used = 0;
}
/* ok read data */
inlen = blksize;
for (i = 0; i < (int)outlen; i++) {
z = 0;
type = list[i].type;
size = list[i].size;
data = list[i].data;
if (!ordered && list[i].used == 1) { continue; }
if (type == LTC_ASN1_EOL) {
break;
}
switch (type) {
case LTC_ASN1_BOOLEAN:
z = inlen;
if ((err = der_decode_boolean(in + x, z, ((int *)data))) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
if ((err = der_length_boolean(&z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_INTEGER:
z = inlen;
if ((err = der_decode_integer(in + x, z, data)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
if ((err = der_length_integer(data, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_SHORT_INTEGER:
z = inlen;
if ((err = der_decode_short_integer(in + x, z, data)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
if ((err = der_length_short_integer(((unsigned long*)data)[0], &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_BIT_STRING:
z = inlen;
if ((err = der_decode_bit_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_bit_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_RAW_BIT_STRING:
z = inlen;
if ((err = der_decode_raw_bit_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_bit_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_OCTET_STRING:
z = inlen;
if ((err = der_decode_octet_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_octet_string(size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_NULL:
if (inlen < 2 || in[x] != 0x05 || in[x+1] != 0x00) {
if (!ordered) { continue; }
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
z = 2;
break;
case LTC_ASN1_OBJECT_IDENTIFIER:
z = inlen;
if ((err = der_decode_object_identifier(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_object_identifier(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_TELETEX_STRING:
z = inlen;
if ((err = der_decode_teletex_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_teletex_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_IA5_STRING:
z = inlen;
if ((err = der_decode_ia5_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_ia5_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_PRINTABLE_STRING:
z = inlen;
if ((err = der_decode_printable_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_printable_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_UTF8_STRING:
z = inlen;
if ((err = der_decode_utf8_string(in + x, z, data, &size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
list[i].size = size;
if ((err = der_length_utf8_string(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_UTCTIME:
z = inlen;
if ((err = der_decode_utctime(in + x, &z, data)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_GENERALIZEDTIME:
z = inlen;
if ((err = der_decode_generalizedtime(in + x, &z, data)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_SET:
z = inlen;
if ((err = der_decode_set(in + x, z, data, size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
if ((err = der_length_sequence(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_SETOF:
case LTC_ASN1_SEQUENCE:
/* detect if we have the right type */
if ((type == LTC_ASN1_SETOF && (in[x] & 0x3F) != 0x31) || (type == LTC_ASN1_SEQUENCE && (in[x] & 0x3F) != 0x30)) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
z = inlen;
if ((err = der_decode_sequence(in + x, z, data, size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
if ((err = der_length_sequence(data, size, &z)) != CRYPT_OK) {
goto LBL_ERR;
}
break;
case LTC_ASN1_CHOICE:
z = inlen;
if ((err = der_decode_choice(in + x, &z, data, size)) != CRYPT_OK) {
if (!ordered) { continue; }
goto LBL_ERR;
}
break;
case LTC_ASN1_CONSTRUCTED:
case LTC_ASN1_CONTEXT_SPECIFIC:
case LTC_ASN1_EOL:
err = CRYPT_INVALID_ARG;
goto LBL_ERR;
}
x += z;
inlen -= z;
list[i].used = 1;
if (!ordered) {
/* restart the decoder */
i = -1;
}
}
for (i = 0; i < (int)outlen; i++) {
if (list[i].used == 0) {
err = CRYPT_INVALID_PACKET;
goto LBL_ERR;
}
}
if (inlen == 0) {
err = CRYPT_OK;
} else {
err = CRYPT_INPUT_TOO_LONG;
}
LBL_ERR:
return err;
}