Commit 06b8d7aa authored by Lev Walkin's avatar Lev Walkin

implemented unber - the ASN.1 BER Decoder

parent 60a1403a
......@@ -10,18 +10,15 @@ AM_CPPFLAGS = \
-I${top_srcdir}/skeletons \
-DDATADIR=\"$(pkgdatadir)\"
LDADD = \
asn1c_LDADD = \
$(top_builddir)/libasn1parser/libasn1parser.la \
$(top_builddir)/libasn1print/libasn1print.la \
$(top_builddir)/libasn1fix/libasn1fix.la \
$(top_builddir)/libasn1compiler/libasn1compiler.la
asn1c_SOURCES = asn1c.c \
tlv_decoder.c tlv_decoder.h
bin_PROGRAMS = asn1c unber
bin_PROGRAMS = asn1c
dist_man1_MANS = asn1c.1
dist_man1_MANS = asn1c.1 unber.1
check_SCRIPTS = check-parsing.sh
TESTS = check-parsing.sh
......
......@@ -14,7 +14,7 @@
@SET_MAKE@
SOURCES = $(asn1c_SOURCES)
SOURCES = asn1c.c unber.c
srcdir = @srcdir@
top_srcdir = @top_srcdir@
......@@ -37,7 +37,7 @@ NORMAL_UNINSTALL = :
PRE_UNINSTALL = :
POST_UNINSTALL = :
host_triplet = @host@
bin_PROGRAMS = asn1c$(EXEEXT)
bin_PROGRAMS = asn1c$(EXEEXT) unber$(EXEEXT)
subdir = asn1c
DIST_COMMON = README $(dist_man1_MANS) $(srcdir)/Makefile.am \
$(srcdir)/Makefile.in
......@@ -51,18 +51,19 @@ CONFIG_CLEAN_FILES =
am__installdirs = "$(DESTDIR)$(bindir)" "$(DESTDIR)$(man1dir)"
binPROGRAMS_INSTALL = $(INSTALL_PROGRAM)
PROGRAMS = $(bin_PROGRAMS)
am_asn1c_OBJECTS = asn1c.$(OBJEXT) tlv_decoder.$(OBJEXT)
asn1c_OBJECTS = $(am_asn1c_OBJECTS)
asn1c_LDADD = $(LDADD)
asn1c_SOURCES = asn1c.c
asn1c_OBJECTS = asn1c.$(OBJEXT)
asn1c_DEPENDENCIES = $(top_builddir)/libasn1parser/libasn1parser.la \
$(top_builddir)/libasn1print/libasn1print.la \
$(top_builddir)/libasn1fix/libasn1fix.la \
$(top_builddir)/libasn1compiler/libasn1compiler.la
unber_SOURCES = unber.c
unber_OBJECTS = unber.$(OBJEXT)
unber_LDADD = $(LDADD)
DEFAULT_INCLUDES = -I. -I$(srcdir) -I$(top_builddir)
depcomp = $(SHELL) $(top_srcdir)/depcomp
am__depfiles_maybe = depfiles
@AMDEP_TRUE@DEP_FILES = ./$(DEPDIR)/asn1c.Po \
@AMDEP_TRUE@ ./$(DEPDIR)/tlv_decoder.Po
@AMDEP_TRUE@DEP_FILES = ./$(DEPDIR)/asn1c.Po ./$(DEPDIR)/unber.Po
COMPILE = $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
$(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS)
LTCOMPILE = $(LIBTOOL) --mode=compile $(CC) $(DEFS) \
......@@ -71,8 +72,8 @@ LTCOMPILE = $(LIBTOOL) --mode=compile $(CC) $(DEFS) \
CCLD = $(CC)
LINK = $(LIBTOOL) --mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) \
$(AM_LDFLAGS) $(LDFLAGS) -o $@
SOURCES = $(asn1c_SOURCES)
DIST_SOURCES = $(asn1c_SOURCES)
SOURCES = asn1c.c unber.c
DIST_SOURCES = asn1c.c unber.c
RECURSIVE_TARGETS = all-recursive check-recursive dvi-recursive \
html-recursive info-recursive install-data-recursive \
install-exec-recursive install-info-recursive \
......@@ -205,16 +206,13 @@ AM_CPPFLAGS = \
-I${top_srcdir}/skeletons \
-DDATADIR=\"$(pkgdatadir)\"
LDADD = \
asn1c_LDADD = \
$(top_builddir)/libasn1parser/libasn1parser.la \
$(top_builddir)/libasn1print/libasn1print.la \
$(top_builddir)/libasn1fix/libasn1fix.la \
$(top_builddir)/libasn1compiler/libasn1compiler.la
asn1c_SOURCES = asn1c.c \
tlv_decoder.c tlv_decoder.h
dist_man1_MANS = asn1c.1
dist_man1_MANS = asn1c.1 unber.1
check_SCRIPTS = check-parsing.sh
TESTS = check-parsing.sh
EXTRA_DIST = check-parsing.sh
......@@ -283,6 +281,9 @@ clean-binPROGRAMS:
asn1c$(EXEEXT): $(asn1c_OBJECTS) $(asn1c_DEPENDENCIES)
@rm -f asn1c$(EXEEXT)
$(LINK) $(asn1c_LDFLAGS) $(asn1c_OBJECTS) $(asn1c_LDADD) $(LIBS)
unber$(EXEEXT): $(unber_OBJECTS) $(unber_DEPENDENCIES)
@rm -f unber$(EXEEXT)
$(LINK) $(unber_LDFLAGS) $(unber_OBJECTS) $(unber_LDADD) $(LIBS)
mostlyclean-compile:
-rm -f *.$(OBJEXT)
......@@ -291,7 +292,7 @@ distclean-compile:
-rm -f *.tab.c
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/asn1c.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/tlv_decoder.Po@am__quote@
@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/unber.Po@am__quote@
.c.o:
@am__fastdepCC_TRUE@ if $(COMPILE) -MT $@ -MD -MP -MF "$(DEPDIR)/$*.Tpo" -c -o $@ $<; \
......
The ASN.1 Compiler
asn1c - The ASN.1 Compiler
unber - The ASN.1 BER Decoder
......@@ -4,9 +4,8 @@
.TH ASN1C 1 "\*(Dt" "ASN.1 Compiler" "ASN.1 Compiler"
.SH NAME
asn1c \- ASN.1 Compiler
.ND ASN.1 compiler
.SH SYNOPSIS
asn1c [\fB\-E\fR [\fB-F\fR] | \fB\-P\fR | \fB\-R\fR | \fB\-t\fR\fIdata-string\fR]
asn1c [\fB\-E\fR [\fB-F\fR] | \fB\-P\fR | \fB\-R\fR]
[\fB\-S\fR\fIdir\fR]
[\fB\-W\fR\fIdebug-\fR...] [\fB\-f\fR\fIoption\fR...] [\fB\-p\fR\fIrint-\fR...]
\fIinfile\fR...
......@@ -19,7 +18,6 @@ and other encoding standards.
\fIOverall Options\fR
\fB\-E \-F \-P \-R\fR
.BI "\-S " directory
.BI "\-t " data-string
.TP
\fIWarning Options\fR
.br
......@@ -55,10 +53,6 @@ omitting the usual support code.
.TP
\fB\-S\fR \fIdirectory\fR
Use the specified directory with ASN.1 skeleton files.
.TP
\fB\-t\fR \fIdata-string\fR
Interpret the data-string as a sequence of hexadecimal values representing
the start of BER TLV encoding. Print the human readable explanation.
.SH WARNING OPTIONS
.TP
.B \-Werror
......@@ -104,5 +98,8 @@ its internal understanding of subtype constraints.
.TP
.B \-print-lines
Generate "-- #line" comments in \fB-E\fR output.
.SH SEE ALSO
.TP
\&\fIunber\fR\|(1)
.SH AUTHORS
Lev Walkin <vlm@lionet.info>
......@@ -19,9 +19,7 @@
#include <asn1c_compat.h> /* Portable basename(3) and dirname(3) */
#include "tlv_decoder.h" /* -t: decode TL[V?] string */
static void usage(char *av0); /* Print the Usage screen and exit(EX_USAGE) */
static void usage(const char *av0); /* Print the Usage screen and exit */
#undef COPYRIGHT
#define COPYRIGHT \
......@@ -45,7 +43,7 @@ main(int ac, char **av) {
/*
* Process command-line options.
*/
while((ch = getopt(ac, av, "EFf:hLPp:RS:t:vW:")) != -1)
while((ch = getopt(ac, av, "EFf:hLPp:RS:vW:")) != -1)
switch(ch) {
case 'E':
print_arg__print_out = 1;
......@@ -97,10 +95,6 @@ main(int ac, char **av) {
case 'S':
skeletons_dir = optarg;
break;
case 't':
if(decode_tlv_from_string(optarg))
exit(EX_DATAERR);
exit(0);
case 'v':
fprintf(stderr, "ASN.1 Compiler, v" VERSION "\n" COPYRIGHT);
exit(0);
......@@ -264,11 +258,11 @@ main(int ac, char **av) {
* Print the usage screen and exit(EX_USAGE).
*/
static void
usage(char *av0) {
usage(const char *av0) {
fprintf(stderr,
"ASN.1 Compiler, v" VERSION "\n" COPYRIGHT
"Usage: %s [options] infile...\n"
"Where [options] are:\n"
"Usage: %s [options] file ...\n"
"Options:\n"
" -E Run only the ASN.1 parser and print out the tree\n"
" -F During -E operation, also perform tree fixing\n"
"\n"
......@@ -278,10 +272,6 @@ usage(char *av0) {
" (Default is \"%s\")\n"
"\n"
" -t <data-string> Decode the given tag[/length] sequence\n"
" (e.g. -t \"bf 20\")\n"
"\n"
" -Werror Treat warnings as errors; abort if any warning\n"
" -Wdebug-lexer Enable verbose debugging output from lexer\n"
" -Wdebug-fixer --//-- semantics processor\n"
......
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <sysexits.h> /* for EX_USAGE */
#include <assert.h>
#include <errno.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <asn1parser.h> /* For static string tables */
#include <asn_types.h>
#include <ber_tlv_tag.h>
#include <ber_tlv_length.h>
#include <ber_tlv_tag.c>
#include <ber_tlv_length.c>
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);
#undef COPYRIGHT
#define COPYRIGHT \
"Copyright (c) 2004 Lev Walkin <vlm@lionet.info>\n"
static char *indent_buffer = " ";
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, "i:t:v")) != -1)
switch(ch) {
case 't':
if(decode_tlv_from_string(optarg))
exit(EX_DATAERR);
exit(0);
case 'i':
i = atoi(optarg);
if(i >= 0 && i < 16) {
indent_buffer = alloca(i + 1);
memset(indent_buffer, ' ', i);
indent_buffer[i] = '\0';
} else {
fprintf(stderr, "-i %s: Invalid indent value\n",optarg);
exit(EX_USAGE);
}
break;
case 'v':
fprintf(stderr, "ASN.1 BER Decoder, v" VERSION "\n" COPYRIGHT);
exit(0);
break;
default:
usage(av[0]);
}
/*
* Ensure that there are some input files present.
*/
if(ac > optind) {
ac -= optind;
av += optind;
} else {
fprintf(stderr, "%s: No input files specified\n", av[0]);
exit(1);
}
setvbuf(stdout, 0, _IOLBF, 0);
/*
* 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);
}
return 0;
}
/*
* Print the usage screen and exit(EX_USAGE).
*/
static void
usage(const char *av0) {
fprintf(stderr,
"ASN.1 BER Decoder, v" VERSION "\n" COPYRIGHT
"Usage: %s [options] [-] [file ...]\n"
"Options:\n"
" -i <indent> Amount of spaces for indentation (default is 4)\n"
" -t <data-string> Decode the given tag[/length] sequence\n"
" (e.g. -t \"bf 20\")\n"
, 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, int level, ssize_t limit);
static void print_TL(int fin, int level, int constr, ssize_t tlen, ber_tlv_tag_t, ber_tlv_len_t);
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;
if(strcmp(fname, "-")) {
fp = fopen(fname, "r");
if(!fp) {
perror(fname);
return -1;
}
} else {
fp = stdin;
}
/*
* Fetch out BER-encoded data until EOF or error.
*/
do {
pdc = process_deeper(fname, fp, 0, -1);
} while(pdc == PD_FINISHED); /* Wait until PD_EOF */
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, int level, ssize_t limit) {
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;
do {
int constr;
int ch;
if(limit == 0)
return PD_FINISHED;
if(limit >= 0 && tblen >= limit) {
fprintf(stderr,
"%s: Too long TL sequence (%ld >= %ld). "
"Dangerous file\n",
fname, (long)tblen, (long)limit);
return PD_FAILED;
}
ch = fgetc(fp);
if(ch == -1) {
if(tblen) {
fprintf(stderr,
"%s: Unexpected end of file (TL)\n",
fname);
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 deciphering tag\n",
fname);
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 deciphering length\n",
fname);
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);
print_TL(0, level, constr, tblen, tlv_tag, tlv_len);
if(limit != -1) {
/* If limit is set, account for the TL sequence */
limit -= (t_len + l_len);
assert(limit >= 0);
}
if(limit != -1) {
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;
} else if(tlv_len != -1) {
/* Account for the V */
limit -= tlv_len;
}
}
if(constr) {
/*
* This is a constructed type. Process recursively.
*/
/* Get the new subframe limit from the structure tags */
if(tlv_len == -1)
tlv_len = limit;
pdc = process_deeper(fname, fp, level + 1, tlv_len);
if(pdc == PD_FAILED) return pdc;
} else {
assert(tlv_len >= 0);
if(print_V(fname, fp, tlv_tag, tlv_len))
return PD_FAILED;
}
print_TL(1, level, constr, tblen, tlv_tag, tlv_len);
tblen = 0;
} while(1);
return pdc;
}
static void
print_TL(int fin, int level, int constr, ssize_t tlen, ber_tlv_tag_t tlv_tag, ber_tlv_len_t tlv_len) {
if(fin && tlen == 2 && !constr && !tlv_tag && !tlv_len) {
/* end of content octets */
return;
}
if(fin && !constr) {
printf("</P>\n");
return;
}
while(level-- > 0) printf(indent_buffer); /* Print indent */
printf(fin ? "</" : "<");
printf(constr ? "C" : "P");
printf(" T=\"");
ber_tlv_tag_fwrite(tlv_tag, stdout);
printf("\"");
if(!fin) {
printf(" tL=\"%ld\"", (long)tlen);
if(tlv_len == -1)
printf(" L=\"Indefinite\"");
else
printf(" L=\"%ld\"", (long)tlv_len);
}
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(" A=\"%s\"", str);
}
if(fin || constr)
printf(">\n");
else
printf(">");
}
static int
print_V(const char *fname, FILE *fp, ber_tlv_tag_t tlv_tag, ber_tlv_len_t tlv_len) {
asn1p_expr_type_e etype = 0;
long collector = 0;
ssize_t i;
/* Figure out what type is it */
if(BER_TAG_CLASS(tlv_tag) == ASN_TAG_CLASS_UNIVERSAL) {
ber_tlv_tag_t tvalue = BER_TAG_VALUE(tlv_tag);
etype = ASN_UNIVERSAL_TAG2TYPE(tvalue);
}
/*
* Print the value in binary or text form.
*/
for(i = 0; i < tlv_len; i++) {
int ch = fgetc(fp);
if(ch == -1) {
fprintf(stderr,
"%s: Unexpected end of file (V)\n", fname);
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_UTF8String:
switch(ch) {
default:
if(((etype == ASN_STRING_UTF8String)
|| !(ch & 0x80))
&& (ch >= 0x20)
) {
printf("%c", ch);
break;
}
/* Fall through */
case '<': case '>': case '&':
printf("&x%02x;", ch);
}
break;
case ASN_BASIC_BOOLEAN:
if(tlv_len == 1) {
switch(ch) {
case 0: printf("<false/>"); break;
case 0xff: printf("<true/>"); break;
default: printf("<true value=\"&x%02x\"/>", ch);
}
break;
}
/* Fall through */
case ASN_BASIC_INTEGER:
case ASN_BASIC_ENUMERATED:
if((size_t)tlv_len <= sizeof(collector)) {
if(i) {
collector = collector * 256 + ch;
} else {
collector = (int)(signed char)ch;
}
if((i+1) == tlv_len)
printf("%ld", collector);
break;
}
/* Fall through */
default:
printf("&x%02x;", ch);
}
}
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++) {
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;
}
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 deciphering 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 deciphering 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;
}
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