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opensc/src/libopensc/asn1.c

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/*
* asn1.c: ASN.1 decoding functions (DER)
*
* Copyright (C) 2001, 2002 Juha Yrjölä <juha.yrjola@iki.fi>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "internal.h"
#include "asn1.h"
#include "log.h"
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include <stdlib.h>
static int asn1_decode(struct sc_context *ctx, struct sc_asn1_entry *asn1,
const u8 *in, size_t len, const u8 **newp, size_t *len_left,
int choice, int depth);
static int asn1_encode(struct sc_context *ctx, const struct sc_asn1_entry *asn1,
u8 **ptr, size_t *size, int depth);
const char *tag2str(int tag)
{
const static char *tags[] = {
"EOC", "BOOLEAN", "INTEGER", "BIT STRING", "OCTET STRING", /* 0-4 */
"NULL", "OBJECT", "OBJECT DESCRIPTOR", "EXTERNAL", "REAL", /* 5-9 */
"ENUMERATED", "<ASN1 11>", "UTF8STRING", "<ASN1 13>", /* 10-13 */
"<ASN1 14>", "<ASN1 15>", "SEQUENCE", "SET", /* 15-17 */
"NUMERICSTRING", "PRINTABLESTRING", "T61STRING", /* 18-20 */
"VIDEOTEXSTRING", "IA5STRING", "UTCTIME", "GENERALIZEDTIME", /* 21-24 */
"GRAPHICSTRING", "VISIBLESTRING", "GENERALSTRING", /* 25-27 */
"UNIVERSALSTRING", "<ASN1 29>", "BMPSTRING" /* 28-30 */
};
if (tag < 0 || tag > 30)
return "(unknown)";
return tags[tag];
}
static int read_tag(const u8 ** buf, size_t buflen, unsigned int *cla_out,
unsigned int *tag_out, size_t *taglen)
{
const u8 *p = *buf;
size_t left = buflen, len;
unsigned int cla, tag, i;
if (left < 2)
goto error;
*buf = NULL;
if (*p == 0)
return 0;
if (*p == 0xFF) /* FIXME */
return 0;
cla = (*p & ASN1_TAG_CLASS) | (*p & ASN1_TAG_CONSTRUCTED);
tag = *p & ASN1_TAG_PRIMITIVE;
if (tag == ASN1_TAG_PRIMITIVE) { /* 0x1F */
fprintf(stderr, "Tag number >= 0x1F not supported!\n");
goto error;
}
p++;
if (--left == 0)
goto error;
len = *p & 0x7f;
if (*p++ & 0x80) {
unsigned int a = 0;
if (len > 4) {
fprintf(stderr, "ASN.1 tag too long!\n");
goto error;
}
for (i = 0; i < len; i++) {
a <<= 8;
a |= *p;
p++;
}
len = a;
}
*cla_out = cla;
*tag_out = tag;
*taglen = len;
*buf = p;
return 1;
error:
return -1;
}
void sc_format_asn1_entry(struct sc_asn1_entry *entry, void *parm, void *arg,
int set_present)
{
entry->parm = parm;
entry->arg = arg;
if (set_present)
entry->flags |= SC_ASN1_PRESENT;
}
void sc_copy_asn1_entry(const struct sc_asn1_entry *src,
struct sc_asn1_entry *dest)
{
while (src->name != NULL) {
*dest = *src;
dest++;
src++;
}
dest->name = NULL;
}
size_t _sc_count_bit_string_size(const void * buf, size_t bufsize)
{
const u8 *p = (const u8 *) buf + bufsize - 1;
u8 c;
size_t skip = 0;
int i;
while (p >= (const u8 *) buf && *p == 0) {
skip += 8;
p--;
}
if (p < (const u8 *) buf)
return 0;
c = *p;
for (i = 0; (c >> (7-i)) == 0; i++);
return bufsize * 8 - (skip + i);
}
static void sc_asn1_print_octet_string(const u8 * buf, size_t buflen)
{
int i;
for (i = 0; i < buflen; i++)
printf("%02X", buf[i]);
}
static void sc_asn1_print_utf8string(const u8 * buf, size_t buflen)
{
int i;
for (i = 0; i < buflen; i++)
printf("%c", buf[i]);
}
static void sc_asn1_print_integer(const u8 * buf, size_t buflen)
{
#ifndef _WIN32
long long a = 0;
#else
__int64 a = 0;
#endif
int i;
if (buflen > sizeof(a)) {
printf("too long");
return;
}
for (i = 0; i < buflen; i++) {
a <<= 8;
a |= buf[i];
}
printf("%lld", a);
}
static void sc_asn1_print_bit_string(const u8 * buf, size_t buflen)
{
#ifndef _WIN32
long long a = 0;
#else
__int64 a = 0;
#endif
int i, r;
if (buflen > sizeof(a) + 1) {
printf("too long");
return;
}
r = sc_asn1_decode_bit_string(buf, buflen, &a, sizeof(a));
if (r < 0) {
printf("decode error");
return;
}
for (i = r - 1; i >= 0; i--) {
printf("%c", ((a >> i) & 1) ? '1' : '0');
}
}
static void sc_asn1_print_object_id(const u8 * buf, size_t buflen)
{
int i = 0;
struct sc_object_id oid;
char sbuf[256];
if (sc_asn1_decode_object_id(buf, buflen, &oid)) {
printf("decode error");
return;
}
sbuf[0] = 0;
while (oid.value[i] >= 0) {
char tmp[12];
if (i)
strcat(sbuf, ".");
sprintf(tmp, "%d", oid.value[i]);
strcat(sbuf, tmp);
i++;
}
printf("%s", sbuf);
}
static void print_tags_recursive(const u8 * buf0, const u8 * buf,
size_t buflen, int depth)
{
int i, r;
size_t bytesleft = buflen;
const char *classes[4] = {
"Univ", "Appl", "Cntx", "Priv"
};
const u8 *p = buf;
while (bytesleft >= 2) {
unsigned int cla, tag, hlen;
const u8 *tagp = p;
size_t len;
r = read_tag(&tagp, bytesleft, &cla, &tag, &len);
if (r < 0) {
printf("Error in decoding.\n");
return;
}
hlen = tagp - p;
if (r == 0)
return;
if (cla == 0 && tag == 0) {
printf("Zero tag, finishing\n");
break;
}
for (i = 0; i < depth; i++) {
putchar(' ');
putchar(' ');
}
printf("%02X %s: tag 0x%02X, length %3d: ",
cla | tag, classes[cla >> 6], tag & 0x1f, len);
if (len + hlen > bytesleft) {
printf(" Illegal length!\n");
return;
}
p += hlen + len;
bytesleft -= hlen + len;
if ((cla & ASN1_TAG_CLASS) == ASN1_TAG_UNIVERSAL)
printf("%s", tag2str(tag));
if (cla & ASN1_TAG_CONSTRUCTED) {
putchar('\n');
print_tags_recursive(buf0, tagp, len, depth + 1);
continue;
}
if ((cla & ASN1_TAG_CLASS) == ASN1_TAG_UNIVERSAL) {
printf(" [");
switch (tag) {
case ASN1_BIT_STRING:
sc_asn1_print_bit_string(tagp, len);
break;
case ASN1_OCTET_STRING:
sc_asn1_print_octet_string(tagp, len);
break;
case ASN1_OBJECT:
sc_asn1_print_object_id(tagp, len);
break;
case ASN1_INTEGER:
case ASN1_ENUMERATED:
sc_asn1_print_integer(tagp, len);
break;
case ASN1_T61STRING:
case ASN1_PRINTABLESTRING:
case ASN1_UTF8STRING:
sc_asn1_print_utf8string(tagp, len);
break;
}
printf("]");
}
putchar('\n');
}
return;
}
void sc_asn1_print_tags(const u8 * buf, size_t buflen)
{
printf("Printing tags for buffer of length %d\n", buflen);
print_tags_recursive(buf, buf, buflen, 0);
}
const u8 *sc_asn1_find_tag(struct sc_context *ctx, const u8 * buf,
size_t buflen, unsigned int tag_in, size_t *taglen_in)
{
size_t left = buflen, taglen;
unsigned int cla, tag;
const u8 *p = buf;
*taglen_in = 0;
while (left >= 2) {
buf = p;
if (read_tag(&p, left, &cla, &tag, &taglen) != 1)
return NULL;
left -= (p - buf);
if ((tag | cla) == tag_in) {
if (taglen > left)
return NULL;
*taglen_in = taglen;
return p;
}
left -= taglen;
p += taglen;
}
return NULL;
}
const u8 *sc_asn1_skip_tag(struct sc_context *ctx, const u8 ** buf, size_t *buflen,
unsigned int tag_in, size_t *taglen_out)
{
const u8 *p = *buf;
size_t len = *buflen, taglen;
unsigned int cla, tag;
if (read_tag((const u8 **) &p, len, &cla, &tag, &taglen) != 1)
return NULL;
switch (cla & 0xC0) {
case ASN1_TAG_UNIVERSAL:
if ((tag_in & SC_ASN1_CLASS_MASK) != SC_ASN1_UNI)
return NULL;
break;
case ASN1_TAG_APPLICATION:
if ((tag_in & SC_ASN1_CLASS_MASK) != SC_ASN1_APP)
return NULL;
break;
case ASN1_TAG_CONTEXT:
if ((tag_in & SC_ASN1_CLASS_MASK) != SC_ASN1_CTX)
return NULL;
break;
case ASN1_TAG_PRIVATE:
if ((tag_in & SC_ASN1_CLASS_MASK) != SC_ASN1_PRV)
return NULL;
break;
}
if (cla & ASN1_TAG_CONSTRUCTED) {
if ((tag_in & SC_ASN1_CONS) == 0)
return NULL;
} else
if (tag_in & SC_ASN1_CONS)
return NULL;
if ((tag_in & SC_ASN1_TAG_MASK) != tag)
return NULL;
len -= (p - *buf); /* header size */
if (taglen > len) {
error(ctx, "too long ASN.1 object (size %d while only %d available)\n",
taglen, len);
return NULL;
}
*buflen -= (p - *buf) + taglen;
*buf = p + taglen; /* point to next tag */
*taglen_out = taglen;
return p;
}
const u8 *sc_asn1_verify_tag(struct sc_context *ctx, const u8 * buf, size_t buflen,
unsigned int tag_in, size_t *taglen_out)
{
return sc_asn1_skip_tag(ctx, &buf, &buflen, tag_in, taglen_out);
}
static int decode_bit_string(const u8 * inbuf, size_t inlen, void *outbuf,
size_t outlen, int invert)
{
const u8 *in = inbuf;
u8 *out = (u8 *) outbuf;
int zero_bits = *in & 0x07;
size_t octets_left = inlen - 1;
int i, count = 0;
memset(outbuf, 0, outlen);
in++;
if (outlen < octets_left)
return SC_ERROR_BUFFER_TOO_SMALL;
if (inlen < 1)
return SC_ERROR_INVALID_ASN1_OBJECT;
while (octets_left) {
/* 1st octet of input: ABCDEFGH, where A is the MSB */
/* 1st octet of output: HGFEDCBA, where A is the LSB */
/* first bit in bit string is the LSB in first resulting octet */
int bits_to_go;
*out = 0;
if (octets_left == 1)
bits_to_go = 8 - zero_bits;
else
bits_to_go = 8;
if (invert)
for (i = 0; i < bits_to_go; i++) {
*out |= ((*in >> (7 - i)) & 1) << i;
}
else {
*out = *in;
}
out++;
in++;
octets_left--;
count++;
}
return (count * 8) - zero_bits;
}
int sc_asn1_decode_bit_string(const u8 * inbuf, size_t inlen,
void *outbuf, size_t outlen)
{
return decode_bit_string(inbuf, inlen, outbuf, outlen, 1);
}
int sc_asn1_decode_bit_string_ni(const u8 * inbuf, size_t inlen,
void *outbuf, size_t outlen)
{
return decode_bit_string(inbuf, inlen, outbuf, outlen, 0);
}
static int encode_bit_string(const u8 * inbuf, size_t bits_left, u8 **outbuf,
size_t *outlen, int invert)
{
const u8 *in = inbuf;
u8 *out;
size_t bytes;
int skipped = 0;
bytes = (bits_left + 7)/8 + 1;
*outbuf = out = (u8 *) malloc(bytes);
if (out == NULL)
return SC_ERROR_OUT_OF_MEMORY;
*outlen = bytes;
out += 1;
while (bits_left) {
int i, bits_to_go = 8;
*out = 0;
if (bits_left < 8) {
bits_to_go = bits_left;
skipped = 8 - bits_left;
}
if (invert) {
for (i = 0; i < bits_to_go; i++)
*out |= ((*in >> i) & 1) << (7 - i);
} else {
*out = *in;
if (bits_left < 8)
return SC_ERROR_NOT_SUPPORTED; /* FIXME */
}
bits_left -= bits_to_go;
out++, in++;
}
out = *outbuf;
out[0] = skipped;
return 0;
}
int sc_asn1_decode_integer(const u8 * inbuf, size_t inlen, int *out)
{
int i, a = 0;
if (inlen > sizeof(int))
return SC_ERROR_INVALID_ASN1_OBJECT;
for (i = 0; i < inlen; i++) {
a <<= 8;
a |= *inbuf++;
}
*out = a;
return 0;
}
static int asn1_encode_integer(int in, u8 ** obj, size_t * objsize)
{
int i = sizeof(in) * 8, skip = 1;
u8 *p, b;
*obj = p = (u8 *) malloc(sizeof(in));
if (*obj == NULL)
return SC_ERROR_OUT_OF_MEMORY;
do {
i -= 8;
b = in >> i;
if (b == 0 && skip)
continue;
skip = 0;
*p++ = b;
} while (i > 0);
*objsize = p - *obj;
if (*objsize == 0) {
*objsize = 1;
(*obj)[0] = 0;
}
return 0;
}
int sc_asn1_decode_object_id(const u8 * inbuf, size_t inlen,
struct sc_object_id *id)
{
int i, a;
const u8 *p = inbuf;
int *octet = id->value;
assert(id != NULL);
if (inlen < 1)
return SC_ERROR_INVALID_ASN1_OBJECT;
for (i = 0; i < SC_MAX_OBJECT_ID_OCTETS; i++)
id->value[i] = -1;
a = *p;
*octet++ = a / 40;
*octet++ = a % 40;
inlen--;
while (inlen) {
p++;
a = *p & 0x7F;
inlen--;
while (inlen && *p & 0x80) {
p++;
a <<= 7;
a |= *p & 0x7F;
inlen--;
}
*octet++ = a;
if (octet - id->value >= SC_MAX_OBJECT_ID_OCTETS-1)
return SC_ERROR_INVALID_ASN1_OBJECT;
};
return 0;
}
int sc_asn1_encode_object_id(u8 **buf, size_t *buflen,
const struct sc_object_id *id)
{
u8 temp[SC_MAX_OBJECT_ID_OCTETS*5], *p = temp;
size_t count = 0;
int *value = (int *) id->value, i = 0;
for (i = 0; value[i] > 0 && i < SC_MAX_OBJECT_ID_OCTETS; i++) {
unsigned int k, shift;
k = value[i];
switch (i) {
case 0:
if (k > 2)
return SC_ERROR_INVALID_ARGUMENTS;
*p = k * 40;
break;
case 1:
if (k > 39)
return SC_ERROR_INVALID_ARGUMENTS;
*p++ += k;
break;
default:
shift = 28;
while (shift && (k >> shift) == 0)
shift -= 7;
while (shift) {
*p++ = 0x80 | ((k >> shift) & 0x7f);
shift -= 7;
}
*p++ = k & 0x7F;
break;
}
}
*buflen = count = p - temp;
*buf = (u8 *) malloc(count);
memcpy(*buf, temp, count);
return 0;
}
int sc_asn1_decode_utf8string(const u8 *inbuf, size_t inlen,
u8 *out, size_t *outlen)
{
if (inlen+1 > *outlen)
return SC_ERROR_BUFFER_TOO_SMALL;
*outlen = inlen+1;
memcpy(out, inbuf, inlen);
out[inlen] = 0;
return 0;
}
int sc_asn1_put_tag(int tag, const u8 * data, int datalen, u8 * out, int outlen, u8 **ptr)
{
u8 *p = out;
if (outlen < 2)
return SC_ERROR_INVALID_ARGUMENTS;
if (datalen < 0 || datalen > 127)
return SC_ERROR_INVALID_ARGUMENTS;
*p++ = tag & 0xFF; /* FIXME: Support longer tags */
outlen--;
*p++ = datalen;
outlen--;
if (outlen < datalen)
return SC_ERROR_INVALID_ARGUMENTS;
memcpy(p, data, datalen);
p += datalen;
if (ptr != NULL)
*ptr = p;
return 0;
}
int asn1_write_element(struct sc_context *ctx, unsigned int tag, const u8 * data,
size_t datalen, u8 ** out, size_t * outlen)
{
u8 t;
u8 *buf, *p;
int c = 0;
t = tag & 0x1F;
if (t != (tag & SC_ASN1_TAG_MASK)) {
error(ctx, "Long tags not supported\n");
return SC_ERROR_INVALID_ARGUMENTS;
}
switch (tag & SC_ASN1_CLASS_MASK) {
case SC_ASN1_UNI:
break;
case SC_ASN1_APP:
t |= ASN1_TAG_APPLICATION;
break;
case SC_ASN1_CTX:
t |= ASN1_TAG_CONTEXT;
break;
case SC_ASN1_PRV:
t |= ASN1_TAG_PRIVATE;
break;
}
if (tag & SC_ASN1_CONS)
t |= ASN1_TAG_CONSTRUCTED;
if (datalen > 127) {
c = 1;
while (datalen >> (c << 3))
c++;
}
*outlen = 2 + c + datalen;
buf = (u8 *) malloc(*outlen);
if (buf == NULL)
SC_FUNC_RETURN(ctx, 1, SC_ERROR_OUT_OF_MEMORY);
*out = p = buf;
*p++ = t;
if (c) {
*p++ = 0x80 | c;
while (c--)
*p++ = (datalen >> (c << 3)) & 0xFF;
} else
*p++ = datalen & 0x7F;
memcpy(p, data, datalen);
return 0;
}
static const struct sc_asn1_entry c_asn1_path[3] = {
{ "path", SC_ASN1_OCTET_STRING, ASN1_OCTET_STRING, 0, NULL },
{ "index", SC_ASN1_INTEGER, ASN1_INTEGER, SC_ASN1_OPTIONAL, NULL },
{ NULL }
};
static int asn1_decode_path(struct sc_context *ctx, const u8 *in, size_t len,
struct sc_path *path, int depth)
{
int idx, r;
struct sc_asn1_entry asn1_path[3];
sc_copy_asn1_entry(c_asn1_path, asn1_path);
sc_format_asn1_entry(asn1_path + 0, &path->value, &path->len, 0);
sc_format_asn1_entry(asn1_path + 1, &idx, NULL, 0);
path->len = SC_MAX_PATH_SIZE;
r = asn1_decode(ctx, asn1_path, in, len, NULL, NULL, 0, depth + 1);
if (r)
return r;
path->type = SC_PATH_TYPE_PATH;
if (asn1_path[1].flags & SC_ASN1_PRESENT)
path->index = idx;
else
path->index = 0;
return 0;
}
static int asn1_encode_path(struct sc_context *ctx, const struct sc_path *path,
u8 **buf, size_t *bufsize, int depth)
{
int r;
struct sc_asn1_entry asn1_path[3];
sc_copy_asn1_entry(c_asn1_path, asn1_path);
sc_format_asn1_entry(asn1_path + 0, (void *) &path->value, (void *) &path->len, 1);
if (path->index)
sc_format_asn1_entry(asn1_path + 1, (void *) &path->index, NULL, 1);
r = asn1_encode(ctx, asn1_path, buf, bufsize, depth + 1);
return r;
}
static const struct sc_asn1_entry c_asn1_com_obj_attr[6] = {
{ "label", SC_ASN1_UTF8STRING, ASN1_UTF8STRING, SC_ASN1_OPTIONAL, NULL },
{ "flags", SC_ASN1_BIT_STRING, ASN1_BIT_STRING, SC_ASN1_OPTIONAL, NULL },
{ "authId", SC_ASN1_PKCS15_ID, ASN1_OCTET_STRING, SC_ASN1_OPTIONAL, NULL },
{ "userConsent", SC_ASN1_INTEGER, ASN1_INTEGER, SC_ASN1_OPTIONAL, NULL },
{ "accessControlRules", SC_ASN1_STRUCT, ASN1_SEQUENCE | SC_ASN1_CONS, SC_ASN1_OPTIONAL, NULL },
{ NULL }
};
static const struct sc_asn1_entry c_asn1_p15_obj[5] = {
{ "commonObjectAttributes", SC_ASN1_STRUCT, ASN1_SEQUENCE | SC_ASN1_CONS, 0, NULL },
{ "classAttributes", SC_ASN1_STRUCT, ASN1_SEQUENCE | SC_ASN1_CONS, 0, NULL },
{ "subClassAttributes", SC_ASN1_STRUCT, SC_ASN1_CTX | 0 | SC_ASN1_CONS, SC_ASN1_OPTIONAL, NULL },
{ "typeAttributes", SC_ASN1_STRUCT, SC_ASN1_CTX | 1 | SC_ASN1_CONS, 0, NULL },
{ NULL }
};
static int asn1_decode_p15_object(struct sc_context *ctx, const u8 *in,
size_t len, struct sc_asn1_pkcs15_object *obj,
int depth)
{
int r;
struct sc_pkcs15_object *p15_obj = obj->p15_obj;
struct sc_asn1_entry asn1_c_attr[6], asn1_p15_obj[5];
size_t flags_len = sizeof(p15_obj->flags);
size_t label_len = sizeof(p15_obj->label);
sc_copy_asn1_entry(c_asn1_com_obj_attr, asn1_c_attr);
sc_copy_asn1_entry(c_asn1_p15_obj, asn1_p15_obj);
sc_format_asn1_entry(asn1_c_attr + 0, p15_obj->label, &label_len, 0);
sc_format_asn1_entry(asn1_c_attr + 1, &p15_obj->flags, &flags_len, 0);
sc_format_asn1_entry(asn1_c_attr + 2, &p15_obj->auth_id, NULL, 0);
sc_format_asn1_entry(asn1_c_attr + 3, &p15_obj->user_consent, NULL, 0);
/* FIXME: encode accessControlRules */
sc_format_asn1_entry(asn1_c_attr + 4, NULL, NULL, 0);
sc_format_asn1_entry(asn1_p15_obj + 0, asn1_c_attr, NULL, 0);
sc_format_asn1_entry(asn1_p15_obj + 1, obj->asn1_class_attr, NULL, 0);
sc_format_asn1_entry(asn1_p15_obj + 2, obj->asn1_subclass_attr, NULL, 0);
sc_format_asn1_entry(asn1_p15_obj + 3, obj->asn1_type_attr, NULL, 0);
r = asn1_decode(ctx, asn1_p15_obj, in, len, NULL, NULL, 0, depth + 1);
return r;
}
static int asn1_encode_p15_object(struct sc_context *ctx, const struct sc_asn1_pkcs15_object *obj,
u8 **buf, size_t *bufsize, int depth)
{
int r;
const struct sc_pkcs15_object *p15_obj = obj->p15_obj;
struct sc_asn1_entry asn1_c_attr[6], asn1_p15_obj[5];
size_t flags_len;
size_t label_len = strlen(p15_obj->label);
sc_copy_asn1_entry(c_asn1_com_obj_attr, asn1_c_attr);
sc_copy_asn1_entry(c_asn1_p15_obj, asn1_p15_obj);
if (label_len != 0)
sc_format_asn1_entry(asn1_c_attr + 0, (void *) p15_obj->label, &label_len, 1);
if (p15_obj->flags) {
flags_len = _sc_count_bit_string_size(&p15_obj->flags, sizeof(p15_obj->flags));
sc_format_asn1_entry(asn1_c_attr + 1, (void *) &p15_obj->flags, &flags_len, 1);
}
if (p15_obj->auth_id.len)
sc_format_asn1_entry(asn1_c_attr + 2, (void *) &p15_obj->auth_id, NULL, 1);
if (p15_obj->user_consent)
sc_format_asn1_entry(asn1_c_attr + 3, (void *) &p15_obj->user_consent, NULL, 1);
/* FIXME: decode accessControlRules */
sc_format_asn1_entry(asn1_p15_obj + 0, asn1_c_attr, NULL, 1);
sc_format_asn1_entry(asn1_p15_obj + 1, obj->asn1_class_attr, NULL, 1);
if (obj->asn1_subclass_attr != NULL)
sc_format_asn1_entry(asn1_p15_obj + 2, obj->asn1_subclass_attr, NULL, 1);
sc_format_asn1_entry(asn1_p15_obj + 3, obj->asn1_type_attr, NULL, 1);
r = asn1_encode(ctx, asn1_p15_obj, buf, bufsize, depth + 1);
return r;
}
static int asn1_decode_entry(struct sc_context *ctx, struct sc_asn1_entry *entry,
const u8 *obj, size_t objlen, int depth)
{
void *parm = entry->parm;
int (*callback_func)(struct sc_context *ctx, void *arg, const u8 *obj,
size_t objlen, int depth) =
(int (*)(struct sc_context *, void *, const u8 *, size_t, int)) parm;
size_t *len = (size_t *) entry->arg;
int r = 0;
if (ctx->debug >= 3) {
u8 line[128], *linep = line;
int i;
line[0] = 0;
for (i = 0; i < depth; i++) {
strcpy((char *) linep, " ");
linep += 2;
}
sprintf((char *) linep, "decoding '%s'\n", entry->name);
debug(ctx, (char *) line);
}
switch (entry->type) {
case SC_ASN1_STRUCT:
if (parm != NULL)
r = asn1_decode(ctx, (struct sc_asn1_entry *) parm, obj,
objlen, NULL, NULL, 0, depth + 1);
break;
case SC_ASN1_NULL:
break;
case SC_ASN1_BOOLEAN:
if (parm != NULL) {
if (objlen != 1) {
error(ctx, "invalid ASN.1 object length: %d\n", objlen);
r = SC_ERROR_INVALID_ASN1_OBJECT;
} else
*((u8 *) parm) = obj[0] ? 1 : 0;
}
break;
case SC_ASN1_INTEGER:
case SC_ASN1_ENUMERATED:
if (parm != NULL)
r = sc_asn1_decode_integer(obj, objlen, (int *) entry->parm);
break;
case SC_ASN1_BIT_STRING_NI:
case SC_ASN1_BIT_STRING:
if (parm != NULL) {
int invert = entry->type == SC_ASN1_BIT_STRING ? 1 : 0;
assert(len != NULL);
if (objlen < 1) {
r = SC_ERROR_INVALID_ASN1_OBJECT;
break;
}
if (entry->flags & SC_ASN1_ALLOC) {
u8 **buf = (u8 **) parm;
*buf = (u8 *) malloc(objlen-1);
if (*buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
*len = objlen-1;
parm = *buf;
}
r = decode_bit_string(obj, objlen, (u8 *) parm, *len, invert);
if (r >= 0) {
*len = r;
r = 0;
}
}
break;
case SC_ASN1_OCTET_STRING:
if (parm != NULL) {
int c;
assert(len != NULL);
if (entry->flags & SC_ASN1_ALLOC) {
u8 **buf = (u8 **) parm;
*buf = (u8 *) malloc(objlen);
if (*buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
c = *len = objlen;
parm = *buf;
} else
c = objlen > *len ? *len : objlen;
memcpy(parm, obj, c);
*len = c;
}
break;
case SC_ASN1_OBJECT:
if (parm != NULL)
r = sc_asn1_decode_object_id(obj, objlen, (struct sc_object_id *) parm);
break;
case SC_ASN1_UTF8STRING:
if (parm != NULL) {
assert(len != NULL);
if (entry->flags & SC_ASN1_ALLOC) {
u8 **buf = (u8 **) parm;
*buf = (u8 *) malloc(objlen-1);
if (*buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
*len = objlen-1;
parm = *buf;
}
r = sc_asn1_decode_utf8string(obj, objlen, (u8 *) parm, len);
}
break;
case SC_ASN1_PATH:
if (entry->parm != NULL)
r = asn1_decode_path(ctx, obj, objlen, (struct sc_path *) parm, depth);
break;
case SC_ASN1_PKCS15_ID:
if (entry->parm != NULL) {
struct sc_pkcs15_id *id = (struct sc_pkcs15_id *) parm;
int c = objlen > sizeof(id->value) ? sizeof(id->value) : objlen;
memcpy(id->value, obj, c);
id->len = c;
}
break;
case SC_ASN1_PKCS15_OBJECT:
if (entry->parm != NULL)
r = asn1_decode_p15_object(ctx, obj, objlen, (struct sc_asn1_pkcs15_object *) parm, depth);
break;
case SC_ASN1_ALGORITHM_ID:
if (entry->parm != NULL)
r = sc_asn1_decode_algorithm_id(ctx, obj, objlen, (struct sc_algorithm_id *) parm, depth);
break;
case SC_ASN1_CALLBACK:
if (entry->parm != NULL)
r = callback_func(ctx, entry->arg, obj, objlen, depth);
break;
default:
error(ctx, "invalid ASN.1 type: %d\n", entry->type);
assert(0);
}
if (r) {
error(ctx, "decoding of ASN.1 object '%s' failed: %s\n", entry->name,
sc_strerror(r));
return r;
}
entry->flags |= SC_ASN1_PRESENT;
return 0;
}
static int asn1_decode(struct sc_context *ctx, struct sc_asn1_entry *asn1,
const u8 *in, size_t len, const u8 **newp, size_t *len_left,
int choice, int depth)
{
int r, idx = 0;
const u8 *p = in, *obj;
struct sc_asn1_entry *entry = asn1;
size_t left = len, objlen;
if (ctx->debug >= 3)
debug(ctx, "called, depth %d%s\n", depth, choice ? ", choice" : "");
if (left < 2) {
if (asn1->name != NULL)
return SC_ERROR_ASN1_END_OF_CONTENTS;
else
return 0;
}
if ((p[0] == 0 && p[1] == 0) || (p[0] == 0xFF && p[1] == 0xFF))
return SC_ERROR_ASN1_END_OF_CONTENTS;
for (idx = 0; asn1[idx].name != NULL; idx++) {
entry = &asn1[idx];
r = 0;
/* Special case CHOICE has no tag */
if (entry->type == SC_ASN1_CHOICE) {
r = asn1_decode(ctx,
(struct sc_asn1_entry *) entry->parm,
p, left, &p, &left, 1, depth + 1);
if (r >= 0)
r = 0;
goto decode_ok;
}
obj = sc_asn1_skip_tag(ctx, &p, &left, entry->tag, &objlen);
if (obj == NULL) {
if (choice)
continue;
if (entry->flags & SC_ASN1_OPTIONAL) {
if (ctx->debug >= 3)
debug(ctx, "optional ASN.1 object '%s' not present\n",
entry->name);
continue;
}
error(ctx, "mandatory ASN.1 object '%s' not found\n", entry->name);
if (ctx->debug && left) {
u8 line[128], *linep = line;
int i;
line[0] = 0;
for (i = 0; i < 10 && i < left; i++) {
sprintf((char *) linep, "%02X ", p[i]);
linep += 3;
}
debug(ctx, "next tag: %s\n", line);
}
SC_FUNC_RETURN(ctx, 3, SC_ERROR_ASN1_OBJECT_NOT_FOUND);
}
r = asn1_decode_entry(ctx, entry, obj, objlen, depth);
decode_ok:
if (r)
return r;
if (choice)
break;
}
if (choice && asn1[idx].name == NULL) /* No match */
SC_FUNC_RETURN(ctx, 3, SC_ERROR_ASN1_OBJECT_NOT_FOUND);
if (newp != NULL)
*newp = p;
if (len_left != NULL)
*len_left = left;
if (choice)
SC_FUNC_RETURN(ctx, 3, idx);
SC_FUNC_RETURN(ctx, 3, 0);
}
int sc_asn1_decode(struct sc_context *ctx, struct sc_asn1_entry *asn1,
const u8 *in, size_t len, const u8 **newp, size_t *len_left)
{
return asn1_decode(ctx, asn1, in, len, newp, len_left, 0, 0);
}
int sc_asn1_decode_choice(struct sc_context *ctx, struct sc_asn1_entry *asn1,
const u8 *in, size_t len, const u8 **newp, size_t *len_left)
{
return asn1_decode(ctx, asn1, in, len, newp, len_left, 1, 0);
}
static int asn1_encode_entry(struct sc_context *ctx, const struct sc_asn1_entry *entry,
u8 **obj, size_t *objlen, int depth)
{
void *parm = entry->parm;
int (*callback_func)(struct sc_context *ctx, void *arg, u8 **obj,
size_t *objlen, int depth) =
(int (*)(struct sc_context *, void *, u8 **, size_t *, int)) parm;
const size_t *len = (const size_t *) entry->arg;
int r = 0;
u8 * buf = NULL;
size_t buflen = 0;
if (ctx->debug >= 3) {
u8 line[128], *linep = line;
int i;
line[0] = 0;
for (i = 0; i < depth; i++) {
strcpy((char *) linep, " ");
linep += 2;
}
sprintf((char *) linep, "encoding '%s'\n", entry->name);
debug(ctx, (char *) line);
}
assert(entry->type == SC_ASN1_NULL || parm != NULL);
switch (entry->type) {
case SC_ASN1_STRUCT:
r = asn1_encode(ctx, (const struct sc_asn1_entry *) parm, &buf,
&buflen, depth + 1);
break;
case SC_ASN1_NULL:
buf = NULL;
buflen = 0;
break;
case SC_ASN1_BOOLEAN:
buf = (u8 *) malloc(1);
if (buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
buf[0] = *((u8 *) parm) ? 0xFF : 0;
buflen = 1;
break;
case SC_ASN1_INTEGER:
case SC_ASN1_ENUMERATED:
r = asn1_encode_integer(*((int *) entry->parm), &buf, &buflen);
break;
case SC_ASN1_BIT_STRING_NI:
case SC_ASN1_BIT_STRING:
assert(len != NULL);
if (entry->type == SC_ASN1_BIT_STRING)
r = encode_bit_string((const u8 *) parm, *len, &buf, &buflen, 1);
else
r = encode_bit_string((const u8 *) parm, *len, &buf, &buflen, 0);
break;
case SC_ASN1_OCTET_STRING:
case SC_ASN1_UTF8STRING:
assert(len != NULL);
buf = (u8 *) malloc(*len);
if (buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
buflen = *len;
memcpy(buf, parm, buflen);
break;
case SC_ASN1_OBJECT:
if (parm != NULL)
r = sc_asn1_encode_object_id(&buf, &buflen, (struct sc_object_id *) parm);
break;
case SC_ASN1_PATH:
r = asn1_encode_path(ctx, (const struct sc_path *) parm, &buf, &buflen, depth);
break;
case SC_ASN1_PKCS15_ID:
if (entry->parm != NULL) {
const struct sc_pkcs15_id *id = (const struct sc_pkcs15_id *) parm;
buf = (u8 *) malloc(id->len);
if (buf == NULL) {
r = SC_ERROR_OUT_OF_MEMORY;
break;
}
memcpy(buf, id->value, id->len);
buflen = id->len;
}
break;
case SC_ASN1_PKCS15_OBJECT:
r = asn1_encode_p15_object(ctx, (const struct sc_asn1_pkcs15_object *) parm, &buf, &buflen, depth);
break;
case SC_ASN1_ALGORITHM_ID:
r = sc_asn1_encode_algorithm_id(ctx, &buf, &buflen, (const struct sc_algorithm_id *) parm, depth);
break;
case SC_ASN1_CALLBACK:
r = callback_func(ctx, entry->arg, &buf, &buflen, depth);
break;
default:
error(ctx, "invalid ASN.1 type: %d\n", entry->type);
assert(0);
}
if (r) {
error(ctx, "encoding of ASN.1 object '%s' failed: %s\n", entry->name,
sc_strerror(r));
if (buf)
free(buf);
return r;
}
r = asn1_write_element(ctx, entry->tag, buf, buflen, obj, objlen);
if (buf)
free(buf);
if (r) {
error(ctx, "error writing ASN.1 tag and length: %s\n", sc_strerror(r));
return r;
}
return 0;
}
static int asn1_encode(struct sc_context *ctx, const struct sc_asn1_entry *asn1,
u8 **ptr, size_t *size, int depth)
{
int r, idx = 0;
u8 *obj, *buf = NULL;
const struct sc_asn1_entry *entry = asn1;
size_t total = 0, objsize;
if (ctx->debug >= 3)
debug(ctx, "called, depth %d\n", depth);
for (idx = 0; asn1[idx].name != NULL; idx++) {
entry = &asn1[idx];
if (!(entry->flags & SC_ASN1_PRESENT))
continue;
r = asn1_encode_entry(ctx, entry, &obj, &objsize, depth);
if (r) {
if (buf != NULL)
free(buf);
return r;
}
buf = (u8 *) realloc(buf, total + objsize);
memcpy(buf + total, obj, objsize);
free(obj);
total += objsize;
}
*ptr = buf;
*size = total;
SC_FUNC_RETURN(ctx, 3, 0);
}
int sc_asn1_encode(struct sc_context *ctx, const struct sc_asn1_entry *asn1,
u8 **ptr, size_t *size)
{
return asn1_encode(ctx, asn1, ptr, size, 0);
}
int _sc_asn1_encode(struct sc_context *ctx, const struct sc_asn1_entry *asn1, u8 **ptr, size_t *size, int depth)
{
return asn1_encode(ctx, asn1, ptr, size, depth);
}
int
_sc_asn1_decode(struct sc_context *ctx, struct sc_asn1_entry *asn1,
const u8 *in, size_t len, const u8 **newp, size_t *left,
int choice, int depth)
{
return asn1_decode(ctx, asn1, in, len, newp, left, choice, depth);
}
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