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weeded the library out of unber program

This commit is contained in:
Lev Walkin 2019-01-21 17:45:31 -08:00
parent 8e1d7591ab
commit ccfaf2ab89
5 changed files with 821 additions and 727 deletions
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4
.gitignore vendored
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@ -36,8 +36,8 @@ stamp-h*
/asn1c/asn1c
# /asn1c-tools
/asn1-tools/enber
/asn1-tools/unber
/asn1-tools/enber/enber
/asn1-tools/unber/unber
# /skeletons
/skeletons/check-*

8
asn1-tools/unber/Makefile.am
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@ -6,6 +6,12 @@ AM_CPPFLAGS = \
-I${top_srcdir}/libasn1parser \
-I${top_srcdir}/skeletons
unber_LDADD = $(top_builddir)/libasn1common/libasn1common.la
noinst_LTLIBRARIES = libasn1-unber-tool.la
libasn1_unber_tool_la_SOURCES = \
libasn1_unber_tool.c libasn1_unber_tool.h
unber_LDADD = libasn1-unber-tool.la \
$(top_builddir)/libasn1common/libasn1common.la
bin_PROGRAMS = unber

754
asn1-tools/unber/libasn1_unber_tool.c Normal file
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@ -0,0 +1,754 @@
/*
* Copyright (c) 2004, 2005, 2006 Lev Walkin <vlm@lionet.info>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include "asn1_common.h"
#include "libasn1_unber_tool.h"
#define ASN_DISABLE_PER_SUPPORT 1
#define ASN_DISABLE_OER_SUPPORT 1
#include <asn1parser.h> /* For static string tables */
#include <asn_application.h>
#include <constraints.c>
#include <ber_tlv_tag.c>
#include <ber_tlv_length.c>
#include <INTEGER.c>
#include <OBJECT_IDENTIFIER.c>
#include <RELATIVE-OID.c>
#include <asn_codecs_prim.c>
#include <asn1p_integer.c>
#include <asn_internal.c>
static int single_type_decoding = 0; /* -1 enables that */
static int minimalistic = 0; /* -m enables that */
static int pretty_printing = 1; /* -p disables that */
static long skip_bytes = 0; /* -s controls that */
static char indent_bytes[16] = " "; /* -i controls that */
void set_minimalistic_output(int v) { minimalistic = v; }
void set_single_type_decoding(int v) { single_type_decoding = v; }
void set_pretty_printing(int v) { pretty_printing = v; }
int set_skip_bytes(long v) { if(v < 0) return -1; skip_bytes = v; return 0; }
int set_indent_size(int indent_size) {
if(indent_size < 0 || indent_size >= (int)sizeof(indent_bytes)) {
return -1;
}
memset(indent_bytes, ' ', indent_size);
indent_bytes[indent_size] = '\0';
return 0;
}
typedef enum pd_code {
PD_FAILED = -1,
PD_FINISHED = 0,
PD_EOF = 1,
} pd_code_e;
static pd_code_e process_deeper(const char *fname, FILE *fp,
size_t *offset, int level,
ssize_t limit, ber_tlv_len_t *frame_size,
ber_tlv_len_t effective_size, int expect_eoc);
static void print_TL(int fin, size_t offset, int level, int constr,
ssize_t tlen, ber_tlv_tag_t, ber_tlv_len_t,
ber_tlv_len_t effective_frame_size);
static int print_V(const char *fname, FILE *fp, ber_tlv_tag_t, ber_tlv_len_t);
/*
* Open the file and initiate recursive processing.
*/
static int
unber_stream(const char *fname, FILE *fp) {
pd_code_e pdc;
size_t offset = 0; /* Stream decoding position */
ber_tlv_len_t frame_size = 0; /* Single frame size */
/*
* Skip the requested amount of bytes.
*/
for(; offset < (size_t)skip_bytes; offset++) {
if(fgetc(fp) == -1) {
fprintf(stderr, "%s: input source (%zu bytes) "
"has less data than \"-s %ld\" switch "
"wants to skip\n",
fname, offset, skip_bytes);
return -1;
}
}
/*
* Fetch out BER-encoded data until EOF or error.
*/
do {
pdc = process_deeper(fname, fp, &offset, 0, -1, &frame_size, 0, 0);
} while(pdc == PD_FINISHED && !single_type_decoding);
if(pdc == PD_FAILED) return -1;
return 0;
}
/*
* Process the TLV recursively.
*/
static pd_code_e
process_deeper(const char *fname, FILE *fp, size_t *offset, int level,
ssize_t limit, ber_tlv_len_t *frame_size,
ber_tlv_len_t effective_size, int expect_eoc) {
unsigned char tagbuf[32];
ssize_t tblen = 0;
pd_code_e pdc = PD_FINISHED;
ber_tlv_tag_t tlv_tag;
ber_tlv_len_t tlv_len;
ssize_t t_len;
ssize_t l_len;
for(;;) {
ber_tlv_len_t local_esize = 0;
int constr;
int ch;
if(limit == 0) return PD_FINISHED;
if(limit >= 0 && tblen >= limit) {
fprintf(stderr,
"%s: Too long TL sequence (%ld >= %ld)"
" at %zu. "
"Broken or maliciously constructed file\n",
fname, (long)tblen, (long)limit, *offset);
return PD_FAILED;
}
/* Get the next byte from the input stream */
ch = fgetc(fp);
if(ch == -1) {
if(limit > 0 || expect_eoc) {
fprintf(stderr,
"%s: Unexpected end of file (TL)"
" at %zu\n",
fname, *offset);
return PD_FAILED;
} else {
return PD_EOF;
}
}
tagbuf[tblen++] = ch;
/*
* Decode the TLV tag.
*/
t_len = ber_fetch_tag(tagbuf, tblen, &tlv_tag);
switch(t_len) {
case -1:
fprintf(stderr,
"%s: Fatal error decoding tag"
" at %zu+%ld\n",
fname, *offset, (long)tblen);
return PD_FAILED;
case 0:
/* More data expected */
continue;
}
/*
* Decode the TLV length.
*/
constr = BER_TLV_CONSTRUCTED(tagbuf);
l_len =
ber_fetch_length(constr, tagbuf + t_len, tblen - t_len, &tlv_len);
switch(l_len) {
case -1:
fprintf(stderr,
"%s: Fatal error decoding value length"
" at %zu\n",
fname, *offset + t_len);
return PD_FAILED;
case 0:
/* More data expected */
continue;
}
/* Make sure the T & L decoders took exactly the whole buffer */
assert((t_len + l_len) == tblen);
if(!expect_eoc || tagbuf[0] || tagbuf[1])
print_TL(0, *offset, level, constr, tblen, tlv_tag, tlv_len,
effective_size);
if(limit != -1) {
/* If limit is set, account for the TL sequence */
limit -= (t_len + l_len);
assert(limit >= 0);
if(tlv_len > limit) {
fprintf(stderr,
"%s: Structure advertizes length (%ld) "
"greater than of a parent container (%ld)\n",
fname, (long)tlv_len, (long)limit);
return PD_FAILED;
}
}
*offset += t_len + l_len;
*frame_size += t_len + l_len;
effective_size += t_len + l_len;
local_esize += t_len + l_len;
if(expect_eoc && !tagbuf[0] && !tagbuf[1]) {
/* End of content octets */
print_TL(1, *offset - 2, level - 1, 1, 2, 0, -1, effective_size);
return PD_FINISHED;
}
if(constr) {
ber_tlv_len_t dec = 0;
/*
* This is a constructed type. Process recursively.
*/
printf(">\n"); /* Close the opening tag */
if(tlv_len != -1 && limit != -1) {
assert(limit >= tlv_len);
}
pdc = process_deeper(fname, fp, offset, level + 1,
tlv_len == -1 ? limit : tlv_len, &dec,
t_len + l_len, tlv_len == -1);
if(pdc == PD_FAILED) return pdc;
if(limit != -1) {
assert(limit >= dec);
limit -= dec;
}
*frame_size += dec;
effective_size += dec;
local_esize += dec;
if(tlv_len == -1) {
tblen = 0;
if(pdc == PD_FINISHED && limit < 0 && !expect_eoc) return pdc;
continue;
}
} else {
assert(tlv_len >= 0);
if(print_V(fname, fp, tlv_tag, tlv_len)) return PD_FAILED;
if(limit != -1) {
assert(limit >= tlv_len);
limit -= tlv_len;
}
*offset += tlv_len;
*frame_size += tlv_len;
effective_size += tlv_len;
local_esize += tlv_len;
}
print_TL(1, *offset, level, constr, tblen, tlv_tag, tlv_len,
local_esize);
tblen = 0;
/* Report success for a single top level TLV */
if(level == 0 && limit == -1 && !expect_eoc) break;
} /* for(;;) */
return pdc;
}
static void
print_TL(int fin, size_t offset, int level, int constr, ssize_t tlen,
ber_tlv_tag_t tlv_tag, ber_tlv_len_t tlv_len,
ber_tlv_len_t effective_size) {
if(fin && !constr) {
printf("</P>\n");
return;
}
while(level-- > 0) fputs(indent_bytes, stdout); /* Print indent */
printf(fin ? "</" : "<");
printf(constr ? ((tlv_len == -1) ? "I" : "C") : "P");
/* Print out the offset of this boundary, even if closing tag */
if(!minimalistic) printf(" O=\"%zu\"", offset);
printf(" T=\"");
ber_tlv_tag_fwrite(tlv_tag, stdout);
printf("\"");
if(!fin || (tlv_len == -1 && !minimalistic))
printf(" TL=\"%ld\"", (long)tlen);
if(!fin) {
if(tlv_len == -1)
printf(" V=\"Indefinite\"");
else
printf(" V=\"%ld\"", (long)tlv_len);
}
if(!minimalistic && BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL) {
const char *str;
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
str = ASN_UNIVERSAL_TAG2STR(tvalue);
if(str) printf(" A=\"%s\"", str);
}
if(fin) {
if(constr && !minimalistic) printf(" L=\"%ld\"", (long)effective_size);
printf(">\n");
}
}
/*
* Print the value in binary form, or reformat for pretty-printing.
*/
static int
print_V(const char *fname, FILE *fp, ber_tlv_tag_t tlv_tag,
ber_tlv_len_t tlv_len) {
asn_oid_arc_t *arcs = 0; /* Object identifier arcs */
unsigned char *vbuf = 0;
asn1p_expr_type_e etype = 0;
asn1c_integer_t collector = 0;
int special_format = 0;
ssize_t i;
/* Figure out what type is it */
if(BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL && pretty_printing) {
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
etype = ASN_UNIVERSAL_TAG2TYPE(tvalue);
}
/*
* Determine how to print the value, either in its native binary form,
* encoded with &xNN characters, or using pretty-printing.
* The basic string types (including "useful types", like UTCTime)
* are excempt from this determination logic, because their alphabets
* are subsets of the XML's native UTF-8 encoding.
*/
switch(etype) {
case ASN_BASIC_BOOLEAN:
if(tlv_len == 1)
special_format = 1;
else
etype = 0;
break;
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
if((size_t)tlv_len <= sizeof(collector))
special_format = 1;
else
etype = 0;
break;
case ASN_BASIC_OBJECT_IDENTIFIER:
case ASN_BASIC_RELATIVE_OID:
if(tlv_len > 0 && tlv_len < 128 * 1024 /* VERY long OID! */) {
arcs = MALLOC(sizeof(*arcs) * (tlv_len + 1));
if(arcs) {
vbuf = MALLOC(tlv_len + 1);
/* Not checking is intentional */
}
}
case ASN_BASIC_UTCTime:
case ASN_BASIC_GeneralizedTime:
case ASN_STRING_NumericString:
case ASN_STRING_PrintableString:
case ASN_STRING_VisibleString:
case ASN_STRING_IA5String:
case ASN_STRING_UTF8String:
break; /* Directly compatible with UTF-8 */
case ASN_STRING_BMPString:
case ASN_STRING_UniversalString:
break; /* Not directly compatible with UTF-8 */
default:
/* Conditionally compatible with UTF-8 */
if(((etype & ASN_STRING_MASK) || (etype == ASN_BASIC_OCTET_STRING) ||
/*
* AUTOMATIC TAGS or IMPLICIT TAGS in effect,
* Treat this primitive type as OCTET_STRING.
*/
(BER_TAG_CLASS(tlv_tag) != ASN_TAG_CLASS_UNIVERSAL
&& pretty_printing))
&& (tlv_len > 0 && tlv_len < 128 * 1024)) {
vbuf = MALLOC(tlv_len + 1);
/* Not checking is intentional */
}
break;
}
/* If collection vbuf is present, defer printing the F flag. */
if(!vbuf) printf(special_format ? " F>" : ">");
/*
* Print the value in binary or text form,
* or collect the bytes into vbuf.
*/
for(i = 0; i < tlv_len; i++) {
int ch = fgetc(fp);
if(ch == -1) {
fprintf(stderr, "%s: Unexpected end of file (V)\n", fname);
if(vbuf) FREEMEM(vbuf);
if(arcs) FREEMEM(arcs);
return -1;
}
switch(etype) {
case ASN_BASIC_UTCTime:
case ASN_BASIC_GeneralizedTime:
case ASN_STRING_NumericString:
case ASN_STRING_PrintableString:
case ASN_STRING_VisibleString:
case ASN_STRING_IA5String:
case ASN_STRING_UTF8String:
switch(ch) {
default:
if(((etype == ASN_STRING_UTF8String) || !(ch & 0x80))
&& (ch >= 0x20)) {
printf("%c", ch);
break;
}
/* Fall through */
case 0x3c:
case 0x3e:
case 0x26:
printf("&#x%02x;", ch);
}
break;
case ASN_BASIC_BOOLEAN:
switch(ch) {
case 0:
printf("<false/>");
break;
case 0xff:
printf("<true/>");
break;
default:
printf("<true value=\"&#x%02x\"/>", ch);
}
break;
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
if(i)
collector = collector * 256 + ch;
else
collector = (int)(signed char)ch;
break;
default:
if(vbuf) {
vbuf[i] = ch;
} else {
printf("&#x%02x;", ch);
}
}
}
/* Do post-processing */
switch(etype) {
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
printf("%s", asn1p_itoa(collector));
break;
case ASN_BASIC_OBJECT_IDENTIFIER:
if(vbuf) {
OBJECT_IDENTIFIER_t oid = {0, 0};
ssize_t arcno;
oid.buf = vbuf;
oid.size = tlv_len;
arcno = OBJECT_IDENTIFIER_get_arcs(&oid, arcs, tlv_len + 1);
if(arcno >= 0) {
assert(arcno <= (tlv_len + 1));
printf(" F>");
for(i = 0; i < arcno; i++) {
if(i) printf(".");
printf("%" PRIu32, arcs[i]);
}
FREEMEM(vbuf);
vbuf = 0;
}
}
break;
case ASN_BASIC_RELATIVE_OID:
if(vbuf) {
RELATIVE_OID_t oid;
int arcno;
oid.buf = vbuf;
oid.size = tlv_len;
arcno = RELATIVE_OID_get_arcs(&oid, arcs, tlv_len);
if(arcno >= 0) {
assert(arcno <= tlv_len);
printf(" F>");
for(i = 0; i < arcno; i++) {
if(i) printf(".");
printf("%" PRIu32, arcs[i]);
}
FREEMEM(vbuf);
vbuf = 0;
}
}
break;
default:
break;
}
/*
* If the buffer was not consumed, print it out.
* It might be an OCTET STRING or other primitive type,
* which might actually be printable, but we need to figure it out.
*/
if(vbuf) {
int binary;
/*
* Check whether the data could be represented as text
*/
binary = -1 * (tlv_len >> 3); /* Threshold is 12.5% binary */
for(i = 0; i < tlv_len; i++) {
switch(vbuf[i]) {
case 0x1b:
binary = 1;
break;
case 0x09:
case 0x0a:
case 0x0d:
continue;
default:
if(vbuf[i] < 0x20 || vbuf[i] >= 0x7f)
if(++binary > 0) /* Way too many */
break;
continue;
}
break;
}
printf(">");
for(i = 0; i < tlv_len; i++) {
if(binary > 0 || vbuf[i] < 0x20 || vbuf[i] >= 0x7f
|| vbuf[i] == 0x26 /* '&' */
|| vbuf[i] == 0x3c /* '<' */
|| vbuf[i] == 0x3e /* '>' */
)
printf("&#x%02x;", vbuf[i]);
else
printf("%c", vbuf[i]);
}
FREEMEM(vbuf);
}
if(arcs) FREEMEM(arcs);
return 0;
}
int
unber_file(const char *fname) {
FILE *fp;
if(strcmp(fname, "-")) {
fp = fopen(fname, "rb");
if(!fp) {
perror(fname);
return -1;
}
} else {
fp = stdin;
}
int ret = unber_stream(fname, fp);
if(fp != stdin) fclose(fp);
return ret;
}
int
decode_tlv_from_hex_string(const char *datastring) {
unsigned char *data, *dp;
size_t dsize; /* Data size */
ssize_t len;
ber_tlv_tag_t tlv_tag;
ber_tlv_len_t tlv_len;
const char *p;
int half;
dsize = strlen(datastring) + 1;
dp = data = CALLOC(1, dsize);
assert(data);
for(half = 0, p = datastring; *p; p++) {
/* clang-format off */
switch(*p) {
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
*dp |= *p - '0'; break;
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
*dp |= *p - 'A' + 10; break;
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
*dp |= *p - 'a' + 10; break;
case ' ': case '\t': case '\r': case '\n':
continue;
default:
fprintf(stderr, "Unexpected symbols in data string:\n");
fprintf(stderr, "%s\n", datastring);
for(dp = data; datastring < p; datastring++, dp++)
*dp = ' ';
*dp = '\0';
fprintf(stderr, "%s^ <- here\n", (char *)data);
return -1;
}
/* clang-format on */
if(half)
dp++;
else
(*dp) <<= 4;
half = !half;
}
assert((size_t)(dp - data) <= dsize);
dsize = dp - data;
printf("BER: ");
for(dp = data; dp < data + dsize; dp++) printf("%02X", *dp);
printf("\n");
len = ber_fetch_tag(data, dsize, &tlv_tag);
switch(len) {
case -1:
fprintf(stderr, "TAG: Fatal error decoding tag\n");
return -1;
case 0:
fprintf(stderr, "TAG: More data expected\n");
return -1;
default:
printf("TAG: ");
ber_tlv_tag_fwrite(tlv_tag, stdout);
if(BER_TLV_CONSTRUCTED(data)) {
printf(" (constructed)");
} else if(dsize >= 2 && data[0] == 0 && data[1] == 0) {
printf(" (end-of-content)");
} else {
printf(" (primitive)");
}
if(BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL) {
const char *str;
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
str = ASN_UNIVERSAL_TAG2STR(tvalue);
if(str) printf(" \"%s\"", str);
}
printf("\n");
}
if(dsize > (size_t)len) {
len = ber_fetch_length(BER_TLV_CONSTRUCTED(data), data + len,
dsize - len, &tlv_len);
switch(len) {
case -1:
fprintf(stderr, "LEN: Fatal error decoding length\n");
return -1;
case 0:
fprintf(stderr, "LEN: More data expected\n");
return -1;
default:
if(tlv_len == (ber_tlv_len_t)-1)
printf("LEN: Indefinite length encoding\n");
else
printf("LEN: %ld bytes\n", (long)tlv_len);
}
}
return 0;
}
/*
* Dummy functions.
*/
asn_dec_rval_t
ber_check_tags(const asn_codec_ctx_t *opt_codec_ctx,
const asn_TYPE_descriptor_t *td, asn_struct_ctx_t *opt_ctx,
const void *ptr, size_t size, int tag_mode, int last_tag_form,
ber_tlv_len_t *last_length, int *opt_tlv_form) {
asn_dec_rval_t rv = {0, 0};
(void)opt_codec_ctx;
(void)td;
(void)opt_ctx;
(void)ptr;
(void)size;
(void)tag_mode;
(void)last_tag_form;
(void)last_length;
(void)opt_tlv_form;
return rv;
}
ssize_t
der_write_tags(const asn_TYPE_descriptor_t *td, size_t slen, int tag_mode,
int last_tag_form, ber_tlv_tag_t tag,
asn_app_consume_bytes_f *cb, void *app_key) {
(void)td;
(void)slen;
(void)tag_mode;
(void)last_tag_form;
(void)tag;
(void)cb;
(void)app_key;
return -1;
}
asn_dec_rval_t
xer_decode_general(const asn_codec_ctx_t *opt_codec_ctx, asn_struct_ctx_t *ctx,
void *struct_key, const char *xml_tag, const void *buf_ptr,
size_t size,
int (*otd)(void *struct_key, const void *chunk_buf,
size_t chunk_size),
ssize_t (*br)(void *struct_key, const void *chunk_buf,
size_t chunk_size, int have_more)) {
asn_dec_rval_t rv = {0, 0};
(void)opt_codec_ctx;
(void)ctx;
(void)struct_key;
(void)xml_tag;
(void)buf_ptr;
(void)size;
(void)otd;
(void)br;
return rv;
}
size_t
xer_whitespace_span(const void *chunk_buf, size_t chunk_size) {
(void)chunk_buf;
(void)chunk_size;
return 0;
}
int
OCTET_STRING_compare(const asn_TYPE_descriptor_t *td, const void *a,
const void *b) {
(void)td;
(void)a;
(void)b;
return 0;
}
intmax_t
asn_random_between(intmax_t a, intmax_t b) {
(void)b;
return a;
};

45
asn1-tools/unber/libasn1_unber_tool.h Normal file
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@ -0,0 +1,45 @@
/*
* Copyright (c) 2004-2019 Lev Walkin <vlm@lionet.info>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/* Set global options. */
void set_minimalistic_output(int v);
void set_single_type_decoding(int v);
void set_pretty_printing(int v);
int set_skip_bytes(long v);
int set_indent_size(int indent_size);
/*
* Convert BER-encoded file into the low level non-standard XML-like structure.
* Primarily used for manual debugging.
*/
int unber_file(const char *fname);
/*
* Decode the TLV given by the given string.
*/
int decode_tlv_from_hex_string(const char *datastring);

737
asn1-tools/unber/unber.c
View File

@ -25,73 +25,45 @@
*
*/
#include "asn1_common.h"
#define ASN_DISABLE_PER_SUPPORT 1
#define ASN_DISABLE_OER_SUPPORT 1
#include <asn1parser.h> /* For static string tables */
#include <asn_application.h>
#include <constraints.c>
#include <ber_tlv_tag.c>
#include <ber_tlv_length.c>
#include <INTEGER.c>
#include <OBJECT_IDENTIFIER.c>
#include <RELATIVE-OID.c>
#include <asn_codecs_prim.c>
#include <asn1p_integer.c>
#include <asn_internal.c>
#include "libasn1_unber_tool.h"
#undef COPYRIGHT
#define COPYRIGHT "Copyright (c) 2004, 2005 Lev Walkin <vlm@lionet.info>\n"
#define COPYRIGHT "Copyright (c) 2004-2019 Lev Walkin <vlm@lionet.info>\n"
static void usage(const char *av0); /* Print the Usage screen and exit */
static int process(const char *fname); /* Perform the BER decoding */
static int decode_tlv_from_string(const char *datastring);
static int single_type_decoding = 0; /* -1 enables that */
static int minimalistic = 0; /* -m enables that */
static int pretty_printing = 1; /* -p disables that */
static long skip_bytes = 0; /* -s controls that */
static char indent_bytes[16] = " "; /* -i controls that */
int
main(int ac, char **av) {
int ch; /* Command line character */
int i; /* Index in some loops */
/*
* Process command-line options.
*/
while((ch = getopt(ac, av, "1hi:mps:t:v")) != -1) switch(ch) {
while((ch = getopt(ac, av, "1hi:mps:t:v")) != -1) {
switch(ch) {
case '1':
single_type_decoding = 1;
set_single_type_decoding(1);
break;
case 'i':
i = atoi(optarg);
if(i >= 0 && i < (int)sizeof(indent_bytes)) {
memset(indent_bytes, ' ', i);
indent_bytes[i] = '\0';
} else {
if(set_indent_size(atoi(optarg)) != 0) {
fprintf(stderr, "-i %s: Invalid indent value\n", optarg);
exit(EX_USAGE);
}
break;
case 'm':
minimalistic = 1;
set_minimalistic_output(1);
break;
case 'p':
pretty_printing = 0;
set_pretty_printing(0);
break;
case 's':
skip_bytes = atol(optarg);
if(skip_bytes < 0) {
if(set_skip_bytes(atol(optarg)) != 0) {
fprintf(stderr, "-s %s: positive value expected\n", optarg);
exit(EX_USAGE);
}
break;
case 't':
if(decode_tlv_from_string(optarg)) exit(EX_DATAERR);
if(decode_tlv_from_hex_string(optarg)) exit(EX_DATAERR);
exit(0);
case 'v':
fprintf(stderr, "ASN.1 BER Decoder, v" VERSION "\n" COPYRIGHT);
@ -101,6 +73,7 @@ main(int ac, char **av) {
default:
usage(av[0]);
}
}
/*
* Ensure that there are some input files present.
@ -119,8 +92,8 @@ main(int ac, char **av) {
* Iterate over input files and parse each.
* All syntax trees from all files will be bundled together.
*/
for(i = 0; i < ac; i++) {
if(process(av[i])) exit(EX_DATAERR);
for(int i = 0; i < ac; i++) {
if(unber_file(av[i])) exit(EX_DATAERR);
}
return 0;
@ -159,687 +132,3 @@ usage(const char *av0) {
exit(EX_USAGE);
}
typedef enum pd_code {
PD_FAILED = -1,
PD_FINISHED = 0,
PD_EOF = 1,
} pd_code_e;
static pd_code_e process_deeper(const char *fname, FILE *fp,
size_t *offset, int level,
ssize_t limit, ber_tlv_len_t *frame_size,
ber_tlv_len_t effective_size, int expect_eoc);
static void print_TL(int fin, size_t offset, int level, int constr,
ssize_t tlen, ber_tlv_tag_t, ber_tlv_len_t,
ber_tlv_len_t effective_frame_size);
static int print_V(const char *fname, FILE *fp, ber_tlv_tag_t, ber_tlv_len_t);
/*
* Open the file and initiate recursive processing.
*/
static int
process(const char *fname) {
FILE *fp;
pd_code_e pdc;
size_t offset = 0; /* Stream decoding position */
ber_tlv_len_t frame_size = 0; /* Single frame size */
if(strcmp(fname, "-")) {
fp = fopen(fname, "rb");
if(!fp) {
perror(fname);
return -1;
}
} else {
fp = stdin;
}
/*
* Skip the requested amount of bytes.
*/
for(; offset < (size_t)skip_bytes; offset++) {
if(fgetc(fp) == -1) {
fprintf(stderr, "%s: input source (%zu bytes) "
"has less data than \"-s %ld\" switch "
"wants to skip\n",
fname, offset, skip_bytes);
if(fp != stdin) fclose(fp);
return -1;
}
}
/*
* Fetch out BER-encoded data until EOF or error.
*/
do {
pdc = process_deeper(fname, fp, &offset, 0, -1, &frame_size, 0, 0);
} while(pdc == PD_FINISHED && !single_type_decoding);
if(fp != stdin) fclose(fp);
if(pdc == PD_FAILED) return -1;
return 0;
}
/*
* Process the TLV recursively.
*/
static pd_code_e
process_deeper(const char *fname, FILE *fp, size_t *offset, int level,
ssize_t limit, ber_tlv_len_t *frame_size,
ber_tlv_len_t effective_size, int expect_eoc) {
unsigned char tagbuf[32];
ssize_t tblen = 0;
pd_code_e pdc = PD_FINISHED;
ber_tlv_tag_t tlv_tag;
ber_tlv_len_t tlv_len;
ssize_t t_len;
ssize_t l_len;
for(;;) {
ber_tlv_len_t local_esize = 0;
int constr;
int ch;
if(limit == 0) return PD_FINISHED;
if(limit >= 0 && tblen >= limit) {
fprintf(stderr,
"%s: Too long TL sequence (%ld >= %ld)"
" at %zu. "
"Broken or maliciously constructed file\n",
fname, (long)tblen, (long)limit, *offset);
return PD_FAILED;
}
/* Get the next byte from the input stream */
ch = fgetc(fp);
if(ch == -1) {
if(limit > 0 || expect_eoc) {
fprintf(stderr,
"%s: Unexpected end of file (TL)"
" at %zu\n",
fname, *offset);
return PD_FAILED;
} else {
return PD_EOF;
}
}
tagbuf[tblen++] = ch;
/*
* Decode the TLV tag.
*/
t_len = ber_fetch_tag(tagbuf, tblen, &tlv_tag);
switch(t_len) {
case -1:
fprintf(stderr,
"%s: Fatal error decoding tag"
" at %zu+%ld\n",
fname, *offset, (long)tblen);
return PD_FAILED;
case 0:
/* More data expected */
continue;
}
/*
* Decode the TLV length.
*/
constr = BER_TLV_CONSTRUCTED(tagbuf);
l_len =
ber_fetch_length(constr, tagbuf + t_len, tblen - t_len, &tlv_len);
switch(l_len) {
case -1:
fprintf(stderr,
"%s: Fatal error decoding value length"
" at %zu\n",
fname, *offset + t_len);
return PD_FAILED;
case 0:
/* More data expected */
continue;
}
/* Make sure the T & L decoders took exactly the whole buffer */
assert((t_len + l_len) == tblen);
if(!expect_eoc || tagbuf[0] || tagbuf[1])
print_TL(0, *offset, level, constr, tblen, tlv_tag, tlv_len,
effective_size);
if(limit != -1) {
/* If limit is set, account for the TL sequence */
limit -= (t_len + l_len);
assert(limit >= 0);
if(tlv_len > limit) {
fprintf(stderr,
"%s: Structure advertizes length (%ld) "
"greater than of a parent container (%ld)\n",
fname, (long)tlv_len, (long)limit);
return PD_FAILED;
}
}
*offset += t_len + l_len;
*frame_size += t_len + l_len;
effective_size += t_len + l_len;
local_esize += t_len + l_len;
if(expect_eoc && !tagbuf[0] && !tagbuf[1]) {
/* End of content octets */
print_TL(1, *offset - 2, level - 1, 1, 2, 0, -1, effective_size);
return PD_FINISHED;
}
if(constr) {
ber_tlv_len_t dec = 0;
/*
* This is a constructed type. Process recursively.
*/
printf(">\n"); /* Close the opening tag */
if(tlv_len != -1 && limit != -1) {
assert(limit >= tlv_len);
}
pdc = process_deeper(fname, fp, offset, level + 1,
tlv_len == -1 ? limit : tlv_len, &dec,
t_len + l_len, tlv_len == -1);
if(pdc == PD_FAILED) return pdc;
if(limit != -1) {
assert(limit >= dec);
limit -= dec;
}
*frame_size += dec;
effective_size += dec;
local_esize += dec;
if(tlv_len == -1) {
tblen = 0;
if(pdc == PD_FINISHED && limit < 0 && !expect_eoc) return pdc;
continue;
}
} else {
assert(tlv_len >= 0);
if(print_V(fname, fp, tlv_tag, tlv_len)) return PD_FAILED;
if(limit != -1) {
assert(limit >= tlv_len);
limit -= tlv_len;
}
*offset += tlv_len;
*frame_size += tlv_len;
effective_size += tlv_len;
local_esize += tlv_len;
}
print_TL(1, *offset, level, constr, tblen, tlv_tag, tlv_len,
local_esize);
tblen = 0;
/* Report success for a single top level TLV */
if(level == 0 && limit == -1 && !expect_eoc) break;
} /* for(;;) */
return pdc;
}
static void
print_TL(int fin, size_t offset, int level, int constr, ssize_t tlen,
ber_tlv_tag_t tlv_tag, ber_tlv_len_t tlv_len,
ber_tlv_len_t effective_size) {
if(fin && !constr) {
printf("</P>\n");
return;
}
while(level-- > 0) fputs(indent_bytes, stdout); /* Print indent */
printf(fin ? "</" : "<");
printf(constr ? ((tlv_len == -1) ? "I" : "C") : "P");
/* Print out the offset of this boundary, even if closing tag */
if(!minimalistic) printf(" O=\"%zu\"", offset);
printf(" T=\"");
ber_tlv_tag_fwrite(tlv_tag, stdout);
printf("\"");
if(!fin || (tlv_len == -1 && !minimalistic))
printf(" TL=\"%ld\"", (long)tlen);
if(!fin) {
if(tlv_len == -1)
printf(" V=\"Indefinite\"");
else
printf(" V=\"%ld\"", (long)tlv_len);
}
if(!minimalistic && BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL) {
const char *str;
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
str = ASN_UNIVERSAL_TAG2STR(tvalue);
if(str) printf(" A=\"%s\"", str);
}
if(fin) {
if(constr && !minimalistic) printf(" L=\"%ld\"", (long)effective_size);
printf(">\n");
}
}
/*
* Print the value in binary form, or reformat for pretty-printing.
*/
static int
print_V(const char *fname, FILE *fp, ber_tlv_tag_t tlv_tag,
ber_tlv_len_t tlv_len) {
asn_oid_arc_t *arcs = 0; /* Object identifier arcs */
unsigned char *vbuf = 0;
asn1p_expr_type_e etype = 0;
asn1c_integer_t collector = 0;
int special_format = 0;
ssize_t i;
/* Figure out what type is it */
if(BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL && pretty_printing) {
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
etype = ASN_UNIVERSAL_TAG2TYPE(tvalue);
}
/*
* Determine how to print the value, either in its native binary form,
* encoded with &xNN characters, or using pretty-printing.
* The basic string types (including "useful types", like UTCTime)
* are excempt from this determination logic, because their alphabets
* are subsets of the XML's native UTF-8 encoding.
*/
switch(etype) {
case ASN_BASIC_BOOLEAN:
if(tlv_len == 1)
special_format = 1;
else
etype = 0;
break;
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
if((size_t)tlv_len <= sizeof(collector))
special_format = 1;
else
etype = 0;
break;
case ASN_BASIC_OBJECT_IDENTIFIER:
case ASN_BASIC_RELATIVE_OID:
if(tlv_len > 0 && tlv_len < 128 * 1024 /* VERY long OID! */) {
arcs = MALLOC(sizeof(*arcs) * (tlv_len + 1));
if(arcs) {
vbuf = MALLOC(tlv_len + 1);
/* Not checking is intentional */
}
}
case ASN_BASIC_UTCTime:
case ASN_BASIC_GeneralizedTime:
case ASN_STRING_NumericString:
case ASN_STRING_PrintableString:
case ASN_STRING_VisibleString:
case ASN_STRING_IA5String:
case ASN_STRING_UTF8String:
break; /* Directly compatible with UTF-8 */
case ASN_STRING_BMPString:
case ASN_STRING_UniversalString:
break; /* Not directly compatible with UTF-8 */
default:
/* Conditionally compatible with UTF-8 */
if(((etype & ASN_STRING_MASK) || (etype == ASN_BASIC_OCTET_STRING) ||
/*
* AUTOMATIC TAGS or IMPLICIT TAGS in effect,
* Treat this primitive type as OCTET_STRING.
*/
(BER_TAG_CLASS(tlv_tag) != ASN_TAG_CLASS_UNIVERSAL
&& pretty_printing))
&& (tlv_len > 0 && tlv_len < 128 * 1024)) {
vbuf = MALLOC(tlv_len + 1);
/* Not checking is intentional */
}
break;
}
/* If collection vbuf is present, defer printing the F flag. */
if(!vbuf) printf(special_format ? " F>" : ">");
/*
* Print the value in binary or text form,
* or collect the bytes into vbuf.
*/
for(i = 0; i < tlv_len; i++) {
int ch = fgetc(fp);
if(ch == -1) {
fprintf(stderr, "%s: Unexpected end of file (V)\n", fname);
if(vbuf) FREEMEM(vbuf);
if(arcs) FREEMEM(arcs);
return -1;
}
switch(etype) {
case ASN_BASIC_UTCTime:
case ASN_BASIC_GeneralizedTime:
case ASN_STRING_NumericString:
case ASN_STRING_PrintableString:
case ASN_STRING_VisibleString:
case ASN_STRING_IA5String:
case ASN_STRING_UTF8String:
switch(ch) {
default:
if(((etype == ASN_STRING_UTF8String) || !(ch & 0x80))
&& (ch >= 0x20)) {
printf("%c", ch);
break;
}
/* Fall through */
case 0x3c:
case 0x3e:
case 0x26:
printf("&#x%02x;", ch);
}
break;
case ASN_BASIC_BOOLEAN:
switch(ch) {
case 0:
printf("<false/>");
break;
case 0xff:
printf("<true/>");
break;
default:
printf("<true value=\"&#x%02x\"/>", ch);
}
break;
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
if(i)
collector = collector * 256 + ch;
else
collector = (int)(signed char)ch;
break;
default:
if(vbuf) {
vbuf[i] = ch;
} else {
printf("&#x%02x;", ch);
}
}
}
/* Do post-processing */
switch(etype) {
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
printf("%s", asn1p_itoa(collector));
break;
case ASN_BASIC_OBJECT_IDENTIFIER:
if(vbuf) {
OBJECT_IDENTIFIER_t oid = {0, 0};
ssize_t arcno;
oid.buf = vbuf;
oid.size = tlv_len;
arcno = OBJECT_IDENTIFIER_get_arcs(&oid, arcs, tlv_len + 1);
if(arcno >= 0) {
assert(arcno <= (tlv_len + 1));
printf(" F>");
for(i = 0; i < arcno; i++) {
if(i) printf(".");
printf("%" PRIu32, arcs[i]);
}
FREEMEM(vbuf);
vbuf = 0;
}
}
break;
case ASN_BASIC_RELATIVE_OID:
if(vbuf) {
RELATIVE_OID_t oid;
int arcno;
oid.buf = vbuf;
oid.size = tlv_len;
arcno = RELATIVE_OID_get_arcs(&oid, arcs, tlv_len);
if(arcno >= 0) {
assert(arcno <= tlv_len);
printf(" F>");
for(i = 0; i < arcno; i++) {
if(i) printf(".");
printf("%" PRIu32, arcs[i]);
}
FREEMEM(vbuf);
vbuf = 0;
}
}
break;
default:
break;
}
/*
* If the buffer was not consumed, print it out.
* It might be an OCTET STRING or other primitive type,
* which might actually be printable, but we need to figure it out.
*/
if(vbuf) {
int binary;
/*
* Check whether the data could be represented as text
*/
binary = -1 * (tlv_len >> 3); /* Threshold is 12.5% binary */
for(i = 0; i < tlv_len; i++) {
switch(vbuf[i]) {
case 0x1b:
binary = 1;
break;
case 0x09:
case 0x0a:
case 0x0d:
continue;
default:
if(vbuf[i] < 0x20 || vbuf[i] >= 0x7f)
if(++binary > 0) /* Way too many */
break;
continue;
}
break;
}
printf(">");
for(i = 0; i < tlv_len; i++) {
if(binary > 0 || vbuf[i] < 0x20 || vbuf[i] >= 0x7f
|| vbuf[i] == 0x26 /* '&' */
|| vbuf[i] == 0x3c /* '<' */
|| vbuf[i] == 0x3e /* '>' */
)
printf("&#x%02x;", vbuf[i]);
else
printf("%c", vbuf[i]);
}
FREEMEM(vbuf);
}
if(arcs) FREEMEM(arcs);
return 0;
}
static int
decode_tlv_from_string(const char *datastring) {
unsigned char *data, *dp;
size_t dsize; /* Data size */
ssize_t len;
ber_tlv_tag_t tlv_tag;
ber_tlv_len_t tlv_len;
const char *p;
int half;
dsize = strlen(datastring) + 1;
dp = data = CALLOC(1, dsize);
assert(data);
for(half = 0, p = datastring; *p; p++) {
/* clang-format off */
switch(*p) {
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
*dp |= *p - '0'; break;
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
*dp |= *p - 'A' + 10; break;
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
*dp |= *p - 'a' + 10; break;
case ' ': case '\t': case '\r': case '\n':
continue;
default:
fprintf(stderr, "Unexpected symbols in data string:\n");
fprintf(stderr, "%s\n", datastring);
for(dp = data; datastring < p; datastring++, dp++)
*dp = ' ';
*dp = '\0';
fprintf(stderr, "%s^ <- here\n", (char *)data);
return -1;
}
/* clang-format on */
if(half)
dp++;
else
(*dp) <<= 4;
half = !half;
}
assert((size_t)(dp - data) <= dsize);
dsize = dp - data;
printf("BER: ");
for(dp = data; dp < data + dsize; dp++) printf("%02X", *dp);
printf("\n");
len = ber_fetch_tag(data, dsize, &tlv_tag);
switch(len) {
case -1:
fprintf(stderr, "TAG: Fatal error decoding tag\n");
return -1;
case 0:
fprintf(stderr, "TAG: More data expected\n");
return -1;
default:
printf("TAG: ");
ber_tlv_tag_fwrite(tlv_tag, stdout);
if(BER_TLV_CONSTRUCTED(data)) {
printf(" (constructed)");
} else if(dsize >= 2 && data[0] == 0 && data[1] == 0) {
printf(" (end-of-content)");
} else {
printf(" (primitive)");
}
if(BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL) {
const char *str;
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
str = ASN_UNIVERSAL_TAG2STR(tvalue);
if(str) printf(" \"%s\"", str);
}
printf("\n");
}
if(dsize > (size_t)len) {
len = ber_fetch_length(BER_TLV_CONSTRUCTED(data), data + len,
dsize - len, &tlv_len);
switch(len) {
case -1:
fprintf(stderr, "LEN: Fatal error decoding length\n");
return -1;
case 0:
fprintf(stderr, "LEN: More data expected\n");
return -1;
default:
if(tlv_len == (ber_tlv_len_t)-1)
printf("LEN: Indefinite length encoding\n");
else
printf("LEN: %ld bytes\n", (long)tlv_len);
}
}
return 0;
}
/*
* Dummy functions.
*/
asn_dec_rval_t
ber_check_tags(const asn_codec_ctx_t *opt_codec_ctx,
const asn_TYPE_descriptor_t *td, asn_struct_ctx_t *opt_ctx,
const void *ptr, size_t size, int tag_mode, int last_tag_form,
ber_tlv_len_t *last_length, int *opt_tlv_form) {
asn_dec_rval_t rv = {0, 0};
(void)opt_codec_ctx;
(void)td;
(void)opt_ctx;
(void)ptr;
(void)size;
(void)tag_mode;
(void)last_tag_form;
(void)last_length;
(void)opt_tlv_form;
return rv;
}
ssize_t
der_write_tags(const asn_TYPE_descriptor_t *td, size_t slen, int tag_mode,
int last_tag_form, ber_tlv_tag_t tag,
asn_app_consume_bytes_f *cb, void *app_key) {
(void)td;
(void)slen;
(void)tag_mode;
(void)last_tag_form;
(void)tag;
(void)cb;
(void)app_key;
return -1;
}
asn_dec_rval_t
xer_decode_general(const asn_codec_ctx_t *opt_codec_ctx, asn_struct_ctx_t *ctx,
void *struct_key, const char *xml_tag, const void *buf_ptr,
size_t size,
int (*otd)(void *struct_key, const void *chunk_buf,
size_t chunk_size),
ssize_t (*br)(void *struct_key, const void *chunk_buf,
size_t chunk_size, int have_more)) {
asn_dec_rval_t rv = {0, 0};
(void)opt_codec_ctx;
(void)ctx;
(void)struct_key;
(void)xml_tag;
(void)buf_ptr;
(void)size;
(void)otd;
(void)br;
return rv;
}
size_t
xer_whitespace_span(const void *chunk_buf, size_t chunk_size) {
(void)chunk_buf;
(void)chunk_size;
return 0;
}
int
OCTET_STRING_compare(const asn_TYPE_descriptor_t *td, const void *a,
const void *b) {
(void)td;
(void)a;
(void)b;
return 0;
}
intmax_t
asn_random_between(intmax_t a, intmax_t b) {
(void)b;
return a;
};