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#undef NDEBUG
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <string.h>
#include <assert.h>
#include <T.h>
uint8_t buf1[] = {
32 | 16, /* [UNIVERSAL 16], constructed */
128, /* L */
/* a INTEGER */
2, /* [UNIVERSAL 2] */
2, /* L */
150,
70,
/* b [2] IMPLICIT BOOLEAN */
128 | 2, /* [2] */
1, /* L */
0xff,
/* c NULL */
5, /* [UNIVERSAL 5] */
0, /* L */
/* d ENUMERATED */
10, /* [UNIVERSAL 10] */
1, /* L */
222,
/* e OCTET STRING */
4, /* [UNIVERSAL 4] */
3, /* L */
'x',
'y',
'z',
/*
* X.690 specifies that inner structures must be tagged by
* stripping off the outer tag for each subsequent level.
*/
/* f [5] IMPLICIT VisibleString */
128 | 32 | 5, /* [5], constructed */
128, /* L indefinite */
26, /* [UNIVERSAL 26] (VisibleString), primitive */
2,
'l',
'o',
32 | 26, /* [UNIVERSAL 26], recursively constructed */
128,
4, /* [UNIVERSAL 4] (OCTET STRING), primitive */
1,
'v',
4, /* [UNIVERSAL 4], primitive */
2,
'e',
'_',
0,
0,
26, /* [UNIVERSAL 26], primitive */
2,
'i',
't',
0,
0,
/* g BIT STRING */
3, /* [UNIVERSAL 3], primitive */
3, /* L */
2, /* Skip 2 bits */
147,
150, /* => 148 */
/* h [7] BIT STRING */
128 | 32 | 7, /* [7], constructed */
128, /* L indefinite */
3, /* [UNIVERSAL 3], primitive */
3, /* L */
0, /* Skip 0 bits */
140,
141,
3, /* [UNIVERSAL 3], primitive */
2, /* L */
1, /* Skip 1 bit */
143, /* => 142 */
0, /* End of h */
0,
0, /* End of the whole structure */
0,
/* Three bytes of planned leftover */
111, 222, 223
};
static void
check(int is_ok, uint8_t *buf, int size, size_t consumed) {
T_t t, *tp;
ber_dec_rval_t rval;
tp = memset(&t, 0, sizeof(t));
fprintf(stderr, "Buf %p (%d)\n", buf, (int)size);
rval = ber_decode(0, &asn_DEF_T, (void **)&tp, buf, size);
fprintf(stderr, "Returned code %d, consumed %d, expected %d\n",
(int)rval.code, (int)rval.consumed, (int)consumed);
if(is_ok) {
assert(rval.code == RC_OK);
assert(rval.consumed == consumed);
assert(strcmp(t.e->buf, "xyz") == 0);
assert(strcmp(t.f->buf, "love_it") == 0);
assert(t.g->size == 2);
assert(t.g->bits_unused == 2);
printf("%d %d\n", t.g->buf[0], t.g->buf[1]);
assert(t.g->buf[0] == 147);
assert(t.g->buf[1] != 150);
assert(t.g->buf[1] == 148);
printf("%d\n", t.h->buf[3]);
assert(t.h->size == 3);
assert(t.h->bits_unused == 1);
assert(t.h->buf[0] == 140);
assert(t.h->buf[1] == 141);
assert(t.h->buf[2] == 142);
} else {
if(rval.code == RC_OK) {
assert(t.a.size != 2
|| !t.d
|| t.d->size != 1
|| !t.e
|| t.e->size != 3
|| !t.f
|| t.f->size != 7
|| !t.g
|| t.g->size != 2
|| !t.h
|| t.h->size != 3
);
}
fprintf(stderr, "%d %d\n", (int)rval.consumed, (int)consumed);
assert(rval.consumed <= consumed);
}
asn_DEF_T.free_struct(&asn_DEF_T, &t, 1);
}
static void
try_corrupt(uint8_t *buf, int size, int allow_consume) {
uint8_t *tmp;
int i;
fprintf(stderr, "\nCorrupting...\n");
tmp = alloca(size);
for(i = 0; i < 1000; i++) {
int loc;
memcpy(tmp, buf, size);
/* Corrupt random _non-value_ location. */
do { loc = random() % size; } while(
loc == 44 /* bit skips */
|| loc == 51 /* bit skips */
|| loc == 56 /* bit skips */
|| tmp[loc] >= 70);
do { tmp[loc] = buf[loc] ^ random(); } while(
(tmp[loc] == buf[loc])
|| (buf[loc] == 0 && tmp[loc] == 0x80));
fprintf(stderr, "\nTry %d: corrupting byte %d (%d->%d)\n",
i, loc, buf[loc], tmp[loc]);
check(0, tmp, size, allow_consume);
}
}
static void
partial_read(uint8_t *buf, size_t size) {
T_t t, *tp;
ber_dec_rval_t rval;
size_t i1, i2;
uint8_t *tbuf1 = alloca(size);
uint8_t *tbuf2 = alloca(size);
uint8_t *tbuf3 = alloca(size);
fprintf(stderr, "\nPartial read sequence...\n");
/*
* Divide the space (size) into three blocks in various combinations:
* |<----->i1<----->i2<----->|
* ^ buf ^ buf+size
* Try to read block by block.
*/
for(i1 = 0; i1 < size; i1++) {
for(i2 = i1; i2 < size; i2++) {
uint8_t *chunk1 = buf;
size_t size1 = i1;
uint8_t *chunk2 = buf + size1;
size_t size2 = i2 - i1;
uint8_t *chunk3 = buf + size1 + size2;
size_t size3 = size - size1 - size2;
fprintf(stderr, "\n%d:{%d, %d, %d}...\n",
(int)size, (int)size1, (int)size2, (int)size3);
memset(tbuf1, 0, size);
memset(tbuf2, 0, size);
memset(tbuf3, 0, size);
memcpy(tbuf1, chunk1, size1);
memcpy(tbuf2, chunk2, size2);
memcpy(tbuf3, chunk3, size3);
tp = memset(&t, 0, sizeof(t));
fprintf(stderr, "=> Chunk 1 (%d):\n", (int)size1);
rval = ber_decode(0, &asn_DEF_T, (void **)&tp,
tbuf1, size1);
assert(rval.code == RC_WMORE);
assert(rval.consumed <= size1);
if(rval.consumed < size1) {
int leftover = size1 - rval.consumed;
memcpy(tbuf2, tbuf1 + rval.consumed, leftover);
memcpy(tbuf2 + leftover, chunk2, size2);
size2 += leftover;
}
fprintf(stderr, "=> Chunk 2 (%d):\n", (int)size2);
rval = ber_decode(0, &asn_DEF_T, (void **)&tp,
tbuf2, size2);
assert(rval.code == RC_WMORE);
assert(rval.consumed <= size2);
if(rval.consumed < size2) {
int leftover = size2 - rval.consumed;
memcpy(tbuf3, tbuf2 + rval.consumed, leftover);
memcpy(tbuf3 + leftover, chunk3, size3);
size3 += leftover;
}
fprintf(stderr, "=> Chunk 3 (%d):\n", (int)size3);
rval = ber_decode(0, &asn_DEF_T, (void **)&tp,
tbuf3, size3);
assert(rval.code == RC_OK);
assert(rval.consumed == size3);
asn_DEF_T.free_struct(&asn_DEF_T, &t, 1);
}
}
}
int
main(int ac, char **av) {
(void)ac; /* Unused argument */
(void)av; /* Unused argument */
/* Check that the full buffer may be decoded normally */
check(1, buf1, sizeof(buf1), sizeof(buf1) - 3);
/* Check that some types of buffer corruptions will lead to failure */
try_corrupt(buf1, sizeof(buf1) - 3, sizeof(buf1) - 3);
/* Split the buffer in parts and check decoder restartability */
partial_read(buf1, sizeof(buf1) - 3);
return 0;
}
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