| /* |
| * This is a generic BER decoder template for any ASN.1 type. |
| * |
| * To compile, please redefine the asn_DEF as shown: |
| * |
| * cc -Dasn_DEF=asn_DEF_MyCustomType -o myTypeDecoder.o -c decoder-template.c |
| */ |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| #include <stdio.h> |
| #include <sys/types.h> |
| #include <unistd.h> /* for getopt */ |
| #include <string.h> /* for strerror(3) */ |
| #include <errno.h> /* for errno */ |
| #include <assert.h> /* for assert(3) */ |
| #include <sysexits.h> /* for EX_* exit codes */ |
| |
| #include <constr_TYPE.h> |
| |
| extern asn_TYPE_descriptor_t asn_DEF; /* ASN.1 type to be decoded */ |
| |
| /* |
| * Open file and parse its BER contens. |
| */ |
| static void *data_decode_from_file(const char *fname, ssize_t suggested_bufsize); |
| |
| int opt_debug; /* -d */ |
| static int opt_check; /* -c */ |
| static int opt_print; /* -p */ |
| static int opt_stack; /* -s */ |
| static int opt_toxml; /* -x */ |
| |
| #define DEBUG(fmt, args...) do { \ |
| if(!opt_debug) break; \ |
| fprintf(stderr, fmt, ##args); \ |
| fprintf(stderr, "\n"); \ |
| } while(0) |
| |
| int |
| main(int ac, char **av) { |
| ssize_t suggested_bufsize = 8192; /* close or equal to stdio buffer */ |
| int number_of_iterations = 1; |
| int num; |
| int ch; |
| |
| /* |
| * Pocess the command-line argments. |
| */ |
| while((ch = getopt(ac, av, "b:cdn:hps:x")) != -1) |
| switch(ch) { |
| case 'b': |
| suggested_bufsize = atoi(optarg); |
| if(suggested_bufsize < 1 |
| || suggested_bufsize > 16 * 1024 * 1024) { |
| fprintf(stderr, |
| "-b %s: Improper buffer size (1..16M)\n", |
| optarg); |
| exit(EX_UNAVAILABLE); |
| } |
| break; |
| case 'c': |
| opt_check = 1; |
| break; |
| case 'd': |
| opt_debug++; /* Double -dd means ASN.1 debug */ |
| break; |
| case 'n': |
| number_of_iterations = atoi(optarg); |
| if(number_of_iterations < 1) { |
| fprintf(stderr, |
| "-n %s: Improper iterations count\n", optarg); |
| exit(EX_UNAVAILABLE); |
| } |
| break; |
| case 'p': |
| opt_print++; |
| break; |
| case 's': |
| opt_stack = atoi(optarg); |
| if(opt_stack <= 0) { |
| fprintf(stderr, |
| "-s %s: Value greater than 0 expected\n", |
| optarg); |
| exit(EX_UNAVAILABLE); |
| } |
| break; |
| case 'x': |
| opt_toxml++; |
| break; |
| case 'h': |
| default: |
| fprintf(stderr, |
| "Usage: %s [options] <data.ber> ...\n" |
| "Where options are:\n" |
| " -b <size> Set the i/o buffer size (default is %ld)\n" |
| " -c Check ASN.1 constraints after decoding\n" |
| " -d Enable debugging (-dd is even better)\n" |
| " -n <num> Process files <num> times\n" |
| " -s <size> Set the stack usage limit\n" |
| " -p Print out the decoded contents\n" |
| " -x Print out as XML\n" |
| , av[0], (long)suggested_bufsize); |
| exit(EX_USAGE); |
| } |
| |
| ac -= optind; |
| av += optind; |
| |
| if(ac < 1) { |
| fprintf(stderr, "Error: missing filename\n"); |
| exit(EX_USAGE); |
| } |
| |
| setvbuf(stdout, 0, _IOLBF, 0); |
| |
| for(num = 0; num < number_of_iterations; num++) { |
| int ac_i; |
| /* |
| * Process all files in turn. |
| */ |
| for(ac_i = 0; ac_i < ac; ac_i++) { |
| char *fname = av[ac_i]; |
| void *structure; |
| |
| /* |
| * Decode the encoded structure from file. |
| */ |
| structure = data_decode_from_file(fname, suggested_bufsize); |
| if(!structure) { |
| /* Error message is already printed */ |
| exit(EX_DATAERR); |
| } |
| |
| fprintf(stderr, "%s: decoded successfully\n", fname); |
| |
| if(opt_print) asn_fprint(stdout, &asn_DEF, structure); |
| |
| if(opt_toxml |
| && xer_fprint(stdout, &asn_DEF, structure)) { |
| fprintf(stderr, "%s: Cannot convert into XML\n", fname); |
| exit(EX_UNAVAILABLE); |
| } |
| |
| /* Check ASN.1 constraints */ |
| if(opt_check) { |
| char errbuf[128]; |
| size_t errlen = sizeof(errbuf); |
| if(asn_check_constraints(&asn_DEF, structure, |
| errbuf, &errlen)) { |
| fprintf(stderr, "%s: ASN.1 constraint " |
| "check failed: %s\n", fname, errbuf); |
| exit(EX_DATAERR); |
| } |
| } |
| |
| asn_DEF.free_struct(&asn_DEF, structure, 0); |
| } |
| } |
| |
| return 0; |
| } |
| |
| |
| static char *buffer; |
| static size_t buf_offset; /* Offset from the start */ |
| static size_t buf_len; /* Length of meaningful contents */ |
| static size_t buf_size; /* Allocated memory */ |
| static off_t buf_shifted; /* Number of bytes ever shifted */ |
| |
| #define bufptr (buffer + buf_offset) |
| #define bufend (buffer + buf_offset + buf_len) |
| |
| /* |
| * Ensure that the buffer contains at least this amoount of free space. |
| */ |
| static void buf_extend(size_t bySize) { |
| |
| DEBUG("buf_extend(%ld) { o=%ld l=%ld s=%ld }", |
| (long)bySize, (long)buf_offset, (long)buf_len, (long)buf_size); |
| |
| if(buf_size >= (buf_offset + buf_len + bySize)) { |
| return; /* Nothing to do */ |
| } else if(bySize <= buf_offset) { |
| DEBUG("\tContents shifted by %ld", (long)buf_offset); |
| |
| /* Shift the buffer contents */ |
| memmove(buffer, buffer + buf_offset, buf_len); |
| buf_shifted += buf_offset; |
| buf_offset = 0; |
| } else { |
| size_t newsize = (buf_size << 2) + bySize; |
| void *p = realloc(buffer, newsize); |
| if(p) { |
| buffer = (char *)p; |
| buf_size = newsize; |
| |
| DEBUG("\tBuffer reallocated to %ld", (long)newsize); |
| } else { |
| perror("realloc()"); |
| exit(EX_OSERR); |
| } |
| } |
| } |
| |
| static void *data_decode_from_file(const char *fname, ssize_t suggested_bufsize) { |
| static char *fbuf; |
| static ssize_t fbuf_size; |
| static asn_codec_ctx_t s_codec_ctx; |
| asn_codec_ctx_t *opt_codec_ctx = 0; |
| void *structure = 0; |
| size_t rd; |
| FILE *fp; |
| |
| if(opt_stack) { |
| s_codec_ctx.max_stack_size = opt_stack; |
| opt_codec_ctx = &s_codec_ctx; |
| } |
| |
| DEBUG("Processing file %s", fname); |
| |
| fp = fopen(fname, "r"); |
| |
| if(!fp) { |
| fprintf(stderr, "%s: %s\n", fname, strerror(errno)); |
| return 0; |
| } |
| |
| /* prepare the file buffer */ |
| if(fbuf_size != suggested_bufsize) { |
| fbuf = (char *)realloc(fbuf, suggested_bufsize); |
| if(!fbuf) { |
| perror("realloc()"); |
| exit(EX_OSERR); |
| } |
| fbuf_size = suggested_bufsize; |
| } |
| |
| buf_shifted = 0; |
| buf_offset = 0; |
| buf_len = 0; |
| |
| while((rd = fread(fbuf, 1, fbuf_size, fp)) || !feof(fp)) { |
| asn_dec_rval_t rval; |
| int using_local_buf; |
| |
| /* |
| * Copy the data over, or use the original buffer. |
| */ |
| if(buf_len) { |
| /* Append the new data into the intermediate buffer */ |
| buf_extend(rd); |
| memcpy(bufend, fbuf, rd); |
| buf_len += rd; |
| |
| rval = ber_decode(opt_codec_ctx, &asn_DEF, |
| (void **)&structure, bufptr, buf_len); |
| DEBUG("ber_decode(%ld) consumed %ld, code %d", |
| (long)buf_len, (long)rval.consumed, rval.code); |
| |
| /* |
| * Adjust position inside the source buffer. |
| */ |
| assert(rval.consumed <= buf_len); |
| buf_offset += rval.consumed; |
| buf_len -= rval.consumed; |
| } else { |
| using_local_buf = 1; |
| |
| /* Feed the chunk of data into a BER decoder routine */ |
| rval = ber_decode(opt_codec_ctx, &asn_DEF, |
| (void **)&structure, fbuf, rd); |
| DEBUG("ber_decode(%ld) consumed %ld, code %d", |
| (long)rd, (long)rval.consumed, rval.code); |
| |
| /* |
| * Switch the remainder into the intermediate buffer. |
| */ |
| if(rval.code != RC_FAIL && rval.consumed < rd) { |
| buf_extend(rd - rval.consumed); |
| memcpy(bufend, |
| fbuf + rval.consumed, |
| rd - rval.consumed); |
| buf_len = rd - rval.consumed; |
| } |
| } |
| |
| switch(rval.code) { |
| case RC_OK: |
| DEBUG("RC_OK, finishing up"); |
| fclose(fp); |
| return structure; |
| case RC_WMORE: |
| DEBUG("RC_WMORE, continuing..."); |
| continue; |
| case RC_FAIL: |
| break; |
| } |
| break; |
| } |
| |
| fclose(fp); |
| |
| /* Clean up partially decoded structure */ |
| asn_DEF.free_struct(&asn_DEF, structure, 0); |
| |
| fprintf(stderr, "%s: " |
| "BER failure past %lld byte\n", |
| fname, (long long)(buf_shifted + buf_offset)); |
| |
| return 0; |
| } |
| |