Files
open5gs/lib/asn1c/common/aper_support.c
2021-01-24 23:43:42 -05:00

280 lines
6.3 KiB
C

/*
* Copyright (c) 2005-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
* Redistribution and modifications are permitted subject to BSD license.
*/
#include <asn_system.h>
#include <asn_internal.h>
#include <aper_support.h>
int32_t
aper_get_align(asn_per_data_t *pd) {
if(pd->nboff & 0x7) {
ASN_DEBUG("Aligning %ld bits", 8 - ((unsigned long)pd->nboff & 0x7));
return per_get_few_bits(pd, 8 - (pd->nboff & 0x7));
}
return 0;
}
ssize_t
aper_get_length(asn_per_data_t *pd, int range, int ebits, int *repeat) {
ssize_t value;
*repeat = 0;
if (range <= 65536 && range >= 0)
return aper_get_nsnnwn(pd, range);
if (aper_get_align(pd) < 0)
return -1;
if(ebits >= 0) return per_get_few_bits(pd, ebits);
value = per_get_few_bits(pd, 8);
if(value < 0) return -1;
if((value & 128) == 0) /* #10.9.3.6 */
return (value & 0x7F);
if((value & 64) == 0) { /* #10.9.3.7 */
value = ((value & 63) << 8) | per_get_few_bits(pd, 8);
if(value < 0) return -1;
return value;
}
value &= 63; /* this is "m" from X.691, #10.9.3.8 */
if(value < 1 || value > 4)
return -1;
*repeat = 1;
return (16384 * value);
}
ssize_t
aper_get_nslength(asn_per_data_t *pd) {
ssize_t length;
ASN_DEBUG("Getting normally small length");
if(per_get_few_bits(pd, 1) == 0) {
length = per_get_few_bits(pd, 6) + 1;
if(length <= 0) return -1;
ASN_DEBUG("l=%ld", length);
return length;
} else {
int repeat;
length = aper_get_length(pd, -1, -1, &repeat);
if(length >= 0 && !repeat) return length;
return -1; /* Error, or do not support >16K extensions */
}
}
#if !defined(USE_OLDER_APER_NSNNWN)
ssize_t
aper_get_nsnnwn(asn_per_data_t *pd, int range) {
ssize_t value;
int bytes = 0;
ASN_DEBUG("getting nsnnwn with range %d", range);
if(range <= 255) {
int i;
if (range < 0) return -1;
/* 1 -> 8 bits */
for (i = 1; i <= 8; i++) {
int upper = 1 << i;
if (upper >= range)
break;
}
value = per_get_few_bits(pd, i);
return value;
} else if (range == 256){
/* 1 byte */
bytes = 1;
} else if (range <= 65536) {
/* 2 bytes */
bytes = 2;
} else {
//return -1;
int length;
/* handle indefinite range */
length = per_get_few_bits(pd, 1);
if (length == 0)
return per_get_few_bits(pd, 6);
if (aper_get_align(pd) < 0)
return -1;
length = per_get_few_bits(pd, 8);
/* the length is not likely to be that big */
if (length > 4)
return -1;
value = 0;
if (per_get_many_bits(pd, (uint8_t *)&value, 0, length * 8) < 0)
return -1;
return value;
}
if (aper_get_align(pd) < 0)
return -1;
value = per_get_few_bits(pd, 8 * bytes);
return value;
}
#else /* old APER codec */
ssize_t
aper_get_nsnnwn(asn_per_data_t *pd, int dummy_range) {
ssize_t value;
ASN_DEBUG("Get the normally small non-negative whole number APER");
value = per_get_few_bits(pd, 7);
if(value & 64) { /* implicit (value < 0) */
value &= 63;
value <<= 2;
value |= per_get_few_bits(pd, 2);
if(value & 128) /* implicit (value < 0) */
return -1;
if(value == 0)
return 0;
if(value >= 3)
return -1;
value = per_get_few_bits(pd, 8 * value);
return value;
}
return value;
}
#endif /* don't use old APER */
int aper_put_align(asn_per_outp_t *po) {
if(po->nboff & 0x7) {
ASN_DEBUG("Aligning %ld bits", 8 - ((unsigned long)po->nboff & 0x7));
if(per_put_few_bits(po, 0x00, (8 - (po->nboff & 0x7))))
return -1;
}
return 0;
}
ssize_t
aper_put_length(asn_per_outp_t *po, int range, size_t length, int *need_eom) {
int dummy = 0;
if(!need_eom) need_eom = &dummy;
*need_eom = 0;
ASN_DEBUG("APER put length %zu with range %d", length, range);
/* 10.9 X.691 Note 2 */
if (range <= 65536 && range >= 0)
return aper_put_nsnnwn(po, range, length);
if (aper_put_align(po) < 0)
return -1;
if(length <= 127) /* #10.9.3.6 */{
return per_put_few_bits(po, length, 8)
? -1 : (ssize_t)length;
}
else if(length < 16384) /* #10.9.3.7 */
return per_put_few_bits(po, length|0x8000, 16)
? -1 : (ssize_t)length;
*need_eom = 0 == (length & 16383);
length >>= 14;
if(length > 4) {
*need_eom = 0;
length = 4;
}
return per_put_few_bits(po, 0xC0 | length, 8)
? -1 : (ssize_t)(length << 14);
}
int
aper_put_nslength(asn_per_outp_t *po, size_t length) {
if(length <= 64) {
/* #10.9.3.4 */
if(length == 0) return -1;
return per_put_few_bits(po, length-1, 7) ? -1 : 0;
} else {
if(aper_put_length(po, -1, length, 0) != (ssize_t)length) {
/* This might happen in case of >16K extensions */
return -1;
}
}
return 0;
}
#if !defined(USE_OLDER_APER_NSNNWN)
int
aper_put_nsnnwn(asn_per_outp_t *po, int range, int number) {
int bytes;
ASN_DEBUG("aper put nsnnwn %d with range %d", number, range);
/* 10.5.7.1 X.691 */
if(range < 0) {
int i;
for (i = 1; ; i++) {
int bits = 1 << (8 * i);
if (number <= bits)
break;
}
bytes = i;
assert(i <= 4);
}
if(range <= 255) {
int i;
for (i = 1; i <= 8; i++) {
int bits = 1 << i;
if (range <= bits)
break;
}
return per_put_few_bits(po, number, i);
} else if(range == 256) {
bytes = 1;
} else if(range <= 65536) {
bytes = 2;
} else { /* Ranges > 64K */
int i;
for (i = 1; ; i++) {
int bits = 1 << (8 * i);
if (range <= bits)
break;
}
assert(i <= 4);
bytes = i;
}
if(aper_put_align(po) < 0) /* Aligning on octet */
return -1;
/* if(per_put_few_bits(po, bytes, 8))
return -1;
*/
return per_put_few_bits(po, number, 8 * bytes);
}
#else /* preserve old code base in case */
int
aper_put_nsnnwn(asn_per_outp_t *po, int dummy_range, int n) {
int bytes;
ASN_DEBUG("aper_put_nsnnwn");
if(n <= 63) {
if(n < 0) return -1;
return per_put_few_bits(po, n, 7);
}
if(n < 256)
bytes = 1;
else if(n < 65536)
bytes = 2;
else if(n < 256 * 65536)
bytes = 3;
else
return -1; /* This is not a "normally small" value */
if(per_put_few_bits(po, bytes, 8))
return -1;
return per_put_few_bits(po, n, 8 * bytes);
}
#endif /* which aper_put_nsnnwn() */