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Diffstat (limited to 'Source/lib/asn1/asn1.c')
-rw-r--r-- | Source/lib/asn1/asn1.c | 738 |
1 files changed, 0 insertions, 738 deletions
diff --git a/Source/lib/asn1/asn1.c b/Source/lib/asn1/asn1.c deleted file mode 100644 index c847461b6..000000000 --- a/Source/lib/asn1/asn1.c +++ /dev/null @@ -1,738 +0,0 @@ -/* Simple ASN.1 parser - * Copyright (C) 2000-2004 Andreas Steffen, Zuercher Hochschule Winterthur - * Copyright (C) 2006 Martin Will, Hochschule fuer Technik Rapperswil - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation; either version 2 of the License, or (at your - * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY - * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * for more details. - */ - -#include <stdlib.h> -#include <string.h> -#include <time.h> - -#include "asn1.h" - -#include <utils/logger_manager.h> - -static logger_t *logger; - -/* Names of the months */ -static const char* months[] = { - "Jan", "Feb", "Mar", "Apr", "May", "Jun", - "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" -}; - -/* some common prefabricated ASN.1 constants */ -static u_char ASN1_INTEGER_0_str[] = { 0x02, 0x00 }; -static u_char ASN1_INTEGER_1_str[] = { 0x02, 0x01, 0x01 }; -static u_char ASN1_INTEGER_2_str[] = { 0x02, 0x01, 0x02 }; - -const chunk_t ASN1_INTEGER_0 = chunk_from_buf(ASN1_INTEGER_0_str); -const chunk_t ASN1_INTEGER_1 = chunk_from_buf(ASN1_INTEGER_1_str); -const chunk_t ASN1_INTEGER_2 = chunk_from_buf(ASN1_INTEGER_2_str); - -/* some popular algorithmIdentifiers */ - -static u_char ASN1_md5_id_str[] = { - 0x30, 0x0C, - 0x06, 0x08, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, - 0x05, 0x00 -}; - -static u_char ASN1_sha1_id_str[] = { - 0x30, 0x09, - 0x06, 0x05, 0x2B, 0x0E,0x03, 0x02, 0x1A, - 0x05, 0x00 -}; - -static u_char ASN1_md5WithRSA_id_str[] = { - 0x30, 0x0D, - 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x04, - 0x05, 0x00 -}; - -static u_char ASN1_sha1WithRSA_id_str[] = { - 0x30, 0x0D, - 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x05, - 0x05, 0x00 -}; - -static u_char ASN1_rsaEncryption_id_str[] = { - 0x30, 0x0D, - 0x06, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01, 0x01, 0x01, - 0x05, 0x00 -}; - -const chunk_t ASN1_md5_id = chunk_from_buf(ASN1_md5_id_str); -const chunk_t ASN1_sha1_id = chunk_from_buf(ASN1_sha1_id_str); -const chunk_t ASN1_rsaEncryption_id = chunk_from_buf(ASN1_rsaEncryption_id_str); -const chunk_t ASN1_md5WithRSA_id = chunk_from_buf(ASN1_md5WithRSA_id_str); -const chunk_t ASN1_sha1WithRSA_id = chunk_from_buf(ASN1_sha1WithRSA_id_str); - -/* ASN.1 definiton of an algorithmIdentifier */ -static const asn1Object_t algorithmIdentifierObjects[] = { - { 0, "algorithmIdentifier", ASN1_SEQUENCE, ASN1_NONE }, /* 0 */ - { 1, "algorithm", ASN1_OID, ASN1_BODY }, /* 1 */ - { 1, "parameters", ASN1_EOC, ASN1_RAW } /* 2 */ -}; - -#define ALGORITHM_ID_ALG 1 -#define ALGORITHM_ID_PARAMETERS 2 -#define ALGORITHM_ID_ROOF 3 - -/* - * return the ASN.1 encoded algorithm identifier - */ -chunk_t asn1_algorithmIdentifier(int oid) -{ - switch (oid) - { - case OID_RSA_ENCRYPTION: - return ASN1_rsaEncryption_id; - case OID_MD5_WITH_RSA: - return ASN1_md5WithRSA_id; - case OID_SHA1_WITH_RSA: - return ASN1_sha1WithRSA_id; - case OID_MD5: - return ASN1_md5_id; - case OID_SHA1: - return ASN1_sha1_id; - default: - return CHUNK_INITIALIZER; - } -} - -/* - * If the oid is listed in the oid_names table then the corresponding - * position in the oid_names table is returned otherwise -1 is returned - */ -int known_oid(chunk_t object) -{ - int oid = 0; - - while (object.len) - { - if (oid_names[oid].octet == *object.ptr) - { - if (--object.len == 0 || oid_names[oid].down == 0) - { - return oid; /* found terminal symbol */ - } - else - { - object.ptr++; oid++; /* advance to next hex octet */ - } - } - else - { - if (oid_names[oid].next) - oid = oid_names[oid].next; - else - return OID_UNKNOWN; - } - } - return -1; -} - -/* - * Decodes the length in bytes of an ASN.1 object - */ -u_int asn1_length(chunk_t *blob) -{ - u_char n; - size_t len; - - /* advance from tag field on to length field */ - blob->ptr++; - blob->len--; - - /* read first octet of length field */ - n = *blob->ptr++; - blob->len--; - - if ((n & 0x80) == 0) - {/* single length octet */ - return n; - } - - /* composite length, determine number of length octets */ - n &= 0x7f; - - if (n > blob->len) - { - logger->log(logger, ERROR|LEVEL1, "number of length octets is larger than ASN.1 object"); - return ASN1_INVALID_LENGTH; - } - - if (n > sizeof(len)) - { - logger->log(logger, ERROR|LEVEL1, "number of length octets is larger than limit of %d octets", - (int)sizeof(len)); - return ASN1_INVALID_LENGTH; - } - - len = 0; - - while (n-- > 0) - { - len = 256*len + *blob->ptr++; - blob->len--; - } - return len; -} - -/* - * determines if a character string is of type ASN.1 printableString - */ -bool is_printablestring(chunk_t str) -{ - const char printablestring_charset[] = - "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789 '()+,-./:=?"; - u_int i; - - for (i = 0; i < str.len; i++) - { - if (strchr(printablestring_charset, str.ptr[i]) == NULL) - return FALSE; - } - return TRUE; -} - -/* - * Display a date either in local or UTC time - * TODO: Does not seem to be thread save - */ -char* timetoa(const time_t *time, bool utc) -{ - static char buf[30]; - - if (*time == 0) - sprintf(buf, "--- -- --:--:--%s----", (utc)?" UTC ":" "); - else - { - struct tm *t = (utc)? gmtime(time) : localtime(time); - sprintf(buf, "%s %02d %02d:%02d:%02d%s%04d", - months[t->tm_mon], t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, - (utc)?" UTC ":" ", t->tm_year + 1900); - } - return buf; -} - -/* - * Converts ASN.1 UTCTIME or GENERALIZEDTIME into calender time - */ -time_t asn1totime(const chunk_t *utctime, asn1_t type) -{ - struct tm t; - time_t tz_offset; - u_char *eot = NULL; - - if ((eot = memchr(utctime->ptr, 'Z', utctime->len)) != NULL) - { - tz_offset = 0; /* Zulu time with a zero time zone offset */ - } - else if ((eot = memchr(utctime->ptr, '+', utctime->len)) != NULL) - { - int tz_hour, tz_min; - - sscanf(eot+1, "%2d%2d", &tz_hour, &tz_min); - tz_offset = 3600*tz_hour + 60*tz_min; /* positive time zone offset */ - } - else if ((eot = memchr(utctime->ptr, '-', utctime->len)) != NULL) - { - int tz_hour, tz_min; - - sscanf(eot+1, "%2d%2d", &tz_hour, &tz_min); - tz_offset = -3600*tz_hour - 60*tz_min; /* negative time zone offset */ - } - else - { - return 0; /* error in time format */ - } - - { - const char* format = (type == ASN1_UTCTIME)? "%2d%2d%2d%2d%2d": - "%4d%2d%2d%2d%2d"; - - sscanf(utctime->ptr, format, &t.tm_year, &t.tm_mon, &t.tm_mday, - &t.tm_hour, &t.tm_min); - } - - /* is there a seconds field? */ - if ((eot - utctime->ptr) == ((type == ASN1_UTCTIME)?12:14)) - { - sscanf(eot-2, "%2d", &t.tm_sec); - } - else - { - t.tm_sec = 0; - } - - /* representation of year */ - if (t.tm_year >= 1900) - { - t.tm_year -= 1900; - } - else if (t.tm_year >= 100) - { - return 0; - } - else if (t.tm_year < 50) - { - t.tm_year += 100; - } - - /* representation of month 0..11*/ - t.tm_mon--; - - /* set daylight saving time to off */ - t.tm_isdst = 0; - - /* compensate timezone */ - - return mktime(&t) - timezone - tz_offset; -} - -/* - * Initializes the internal context of the ASN.1 parser - */ -void asn1_init(asn1_ctx_t *ctx, chunk_t blob, u_int level0, bool implicit) -{ - logger = logger_manager->get_logger(logger_manager, ASN1); - ctx->blobs[0] = blob; - ctx->level0 = level0; - ctx->implicit = implicit; - memset(ctx->loopAddr, '\0', sizeof(ctx->loopAddr)); -} - -/* - * print the value of an ASN.1 simple object - */ -static void debug_asn1_simple_object(chunk_t object, asn1_t type) -{ - int oid; - time_t time; - - switch (type) - { - case ASN1_OID: - oid = known_oid(object); - if (oid != OID_UNKNOWN) - { - logger->log(logger, CONTROL|LEVEL1, " '%s'", oid_names[oid].name); - return; - } - break; - case ASN1_UTF8STRING: - case ASN1_IA5STRING: - case ASN1_PRINTABLESTRING: - case ASN1_T61STRING: - case ASN1_VISIBLESTRING: - logger->log(logger, CONTROL|LEVEL1, " '%.*s'", (int)object.len, object.ptr); - return; - case ASN1_UTCTIME: - case ASN1_GENERALIZEDTIME: - time = asn1totime(&object, type); - logger->log(logger, CONTROL|LEVEL1, " '%s'", timetoa(&time, TRUE)); - return; - default: - break; - } - logger->log_chunk(logger, RAW|LEVEL1, "", object); -} - -/* - * Parses and extracts the next ASN.1 object - */ -bool extract_object(asn1Object_t const *objects, u_int *objectID, chunk_t *object, u_int *level, asn1_ctx_t *ctx) -{ - asn1Object_t obj = objects[*objectID]; - chunk_t *blob; - chunk_t *blob1; - u_char *start_ptr; - - *object = CHUNK_INITIALIZER; - - if (obj.flags & ASN1_END) /* end of loop or option found */ - { - if (ctx->loopAddr[obj.level] && ctx->blobs[obj.level+1].len > 0) - { - *objectID = ctx->loopAddr[obj.level]; /* another iteration */ - obj = objects[*objectID]; - } - else - { - ctx->loopAddr[obj.level] = 0; /* exit loop or option*/ - return TRUE; - } - } - - *level = ctx->level0 + obj.level; - blob = ctx->blobs + obj.level; - blob1 = blob + 1; - start_ptr = blob->ptr; - - /* handle ASN.1 defaults values */ - if ((obj.flags & ASN1_DEF) && (blob->len == 0 || *start_ptr != obj.type) ) - { - /* field is missing */ - logger->log(logger, CONTROL|LEVEL1, "L%d - %s:", *level, obj.name); - if (obj.type & ASN1_CONSTRUCTED) - { - (*objectID)++ ; /* skip context-specific tag */ - } - return TRUE; - } - - /* handle ASN.1 options */ - - if ((obj.flags & ASN1_OPT) - && (blob->len == 0 || *start_ptr != obj.type)) - { - /* advance to end of missing option field */ - do - (*objectID)++; - while (!((objects[*objectID].flags & ASN1_END) - && (objects[*objectID].level == obj.level))); - return TRUE; - } - - /* an ASN.1 object must possess at least a tag and length field */ - - if (blob->len < 2) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: ASN.1 object smaller than 2 octets", - *level, obj.name); - return FALSE; - } - - blob1->len = asn1_length(blob); - - if (blob1->len == ASN1_INVALID_LENGTH || blob->len < blob1->len) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: length of ASN.1 object invalid or too large", - *level, obj.name); - return FALSE; - } - - blob1->ptr = blob->ptr; - blob->ptr += blob1->len; - blob->len -= blob1->len; - - /* return raw ASN.1 object without prior type checking */ - - if (obj.flags & ASN1_RAW) - { - logger->log(logger, CONTROL|LEVEL1, "L%d - %s:", *level, obj.name); - object->ptr = start_ptr; - object->len = (size_t)(blob->ptr - start_ptr); - return TRUE; - } - - if (*start_ptr != obj.type && !(ctx->implicit && *objectID == 0)) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: ASN1 tag 0x%02x expected, but is 0x%02x", - *level, obj.name, obj.type, *start_ptr); - logger->log_bytes(logger, RAW|LEVEL1, "", start_ptr, (u_int)(blob->ptr - start_ptr)); - return FALSE; - } - - logger->log(logger, CONTROL|LEVEL1, "L%d - %s:", ctx->level0+obj.level, obj.name); - - /* In case of "SEQUENCE OF" or "SET OF" start a loop */ - if (obj.flags & ASN1_LOOP) - { - if (blob1->len > 0) - { - /* at least one item, start the loop */ - ctx->loopAddr[obj.level] = *objectID + 1; - } - else - { - /* no items, advance directly to end of loop */ - do - (*objectID)++; - while (!((objects[*objectID].flags & ASN1_END) - && (objects[*objectID].level == obj.level))); - return TRUE; - } - } - - if (obj.flags & ASN1_OBJ) - { - object->ptr = start_ptr; - object->len = (size_t)(blob->ptr - start_ptr); - logger->log_chunk(logger, RAW|LEVEL1, "", *object); - } - else if (obj.flags & ASN1_BODY) - { - *object = *blob1; - debug_asn1_simple_object(*object, obj.type); - } - return TRUE; -} - -/* - * parse an ASN.1 simple type - */ -bool parse_asn1_simple_object(chunk_t *object, asn1_t type, u_int level, const char* name) -{ - size_t len; - - /* an ASN.1 object must possess at least a tag and length field */ - if (object->len < 2) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: ASN.1 object smaller than 2 octets", - level, name); - return FALSE; - } - - if (*object->ptr != type) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: ASN1 tag 0x%02x expected, but is 0x%02x", - level, name, type, *object->ptr); - return FALSE; - } - - len = asn1_length(object); - - if (len == ASN1_INVALID_LENGTH || object->len < len) - { - logger->log(logger, ERROR|LEVEL1, "L%d - %s: length of ASN.1 object invalid or too large", - level, name); - return FALSE; - } - - logger->log(logger, CONTROL|LEVEL1, "L%d - %s:", level, name); - debug_asn1_simple_object(*object, type); - return TRUE; -} - -/* - * extracts an algorithmIdentifier - */ -int parse_algorithmIdentifier(chunk_t blob, int level0, chunk_t *parameters) -{ - asn1_ctx_t ctx; - chunk_t object; - u_int level; - int alg = OID_UNKNOWN; - int objectID = 0; - - asn1_init(&ctx, blob, level0, FALSE); - - while (objectID < ALGORITHM_ID_ROOF) - { - if (!extract_object(algorithmIdentifierObjects, &objectID, &object, &level, &ctx)) - return OID_UNKNOWN; - - switch (objectID) - { - case ALGORITHM_ID_ALG: - alg = known_oid(object); - break; - case ALGORITHM_ID_PARAMETERS: - if (parameters != NULL) - *parameters = object; - break; - default: - break; - } - objectID++; - } - return alg; - } - -/* - * tests if a blob contains a valid ASN.1 set or sequence - */ -bool is_asn1(chunk_t blob) -{ - u_int len; - u_char tag = *blob.ptr; - - if (tag != ASN1_SEQUENCE && tag != ASN1_SET) - { - logger->log(logger, ERROR|LEVEL2, " file content is not binary ASN.1"); - return FALSE; - } - len = asn1_length(&blob); - if (len != blob.len) - { - logger->log(logger, ERROR|LEVEL2, " file size does not match ASN.1 coded length"); - return FALSE; - } - return TRUE; -} - -/* - * codes ASN.1 lengths up to a size of 16'777'215 bytes - */ -void code_asn1_length(size_t length, chunk_t *code) -{ - if (length < 128) - { - code->ptr[0] = length; - code->len = 1; - } - else if (length < 256) - { - code->ptr[0] = 0x81; - code->ptr[1] = (u_char) length; - code->len = 2; - } - else if (length < 65536) - { - code->ptr[0] = 0x82; - code->ptr[1] = length >> 8; - code->ptr[2] = length & 0x00ff; - code->len = 3; - } - else - { - code->ptr[0] = 0x83; - code->ptr[1] = length >> 16; - code->ptr[2] = (length >> 8) & 0x00ff; - code->ptr[3] = length & 0x0000ff; - code->len = 4; - } -} - -/* - * build an empty asn.1 object with tag and length fields already filled in - */ -u_char* build_asn1_object(chunk_t *object, asn1_t type, size_t datalen) -{ - u_char length_buf[4]; - chunk_t length = { length_buf, 0 }; - u_char *pos; - - /* code the asn.1 length field */ - code_asn1_length(datalen, &length); - - /* allocate memory for the asn.1 TLV object */ - object->len = 1 + length.len + datalen; - object->ptr = malloc(object->len); - - /* set position pointer at the start of the object */ - pos = object->ptr; - - /* copy the asn.1 tag field and advance the pointer */ - *pos++ = type; - - /* copy the asn.1 length field and advance the pointer */ - memcpy(pos, length.ptr, length.len); - pos += length.len; - - return pos; -} - -/* - * build a simple ASN.1 object - */ -chunk_t asn1_simple_object(asn1_t tag, chunk_t content) -{ - chunk_t object; - - u_char *pos = build_asn1_object(&object, tag, content.len); - memcpy(pos, content.ptr, content.len); - pos += content.len; - - return object; -} - -/* Build an ASN.1 object from a variable number of individual chunks. - * Depending on the mode, chunks either are moved ('m') or copied ('c'). - */ -chunk_t asn1_wrap(asn1_t type, const char *mode, ...) -{ - chunk_t construct; - va_list chunks; - u_char *pos; - int i; - int count = strlen(mode); - - /* sum up lengths of individual chunks */ - va_start(chunks, mode); - construct.len = 0; - for (i = 0; i < count; i++) - { - chunk_t ch = va_arg(chunks, chunk_t); - construct.len += ch.len; - } - va_end(chunks); - - /* allocate needed memory for construct */ - pos = build_asn1_object(&construct, type, construct.len); - - /* copy or move the chunks */ - va_start(chunks, mode); - for (i = 0; i < count; i++) - { - chunk_t ch = va_arg(chunks, chunk_t); - - switch (*mode++) - { - case 'm': - memcpy(pos, ch.ptr, ch.len); - pos += ch.len; - free(ch.ptr); - break; - case 'c': - default: - memcpy(pos, ch.ptr, ch.len); - pos += ch.len; - } - } - va_end(chunks); - - return construct; -} - -/* - * convert a MP integer into a DER coded ASN.1 object - */ -chunk_t asn1_integer_from_mpz(const mpz_t value) -{ - size_t bits = mpz_sizeinbase(value, 2); /* size in bits */ - chunk_t n; - n.len = 1 + bits / 8; /* size in bytes */ - n.ptr = mpz_export(NULL, NULL, 1, n.len, 1, 0, value); - - return asn1_wrap(ASN1_INTEGER, "m", n); -} - -/* - * convert a date into ASN.1 UTCTIME or GENERALIZEDTIME format - */ -chunk_t timetoasn1(const time_t *time, asn1_t type) -{ - int offset; - const char *format; - char buf[TIMETOA_BUF]; - chunk_t formatted_time; - struct tm *t = gmtime(time); - - if (type == ASN1_GENERALIZEDTIME) - { - format = "%04d%02d%02d%02d%02d%02dZ"; - offset = 1900; - } - else /* ASN1_UTCTIME */ - { - format = "%02d%02d%02d%02d%02d%02dZ"; - offset = (t->tm_year < 100)? 0 : -100; - } - sprintf(buf, format, t->tm_year + offset, t->tm_mon + 1, t->tm_mday - , t->tm_hour, t->tm_min, t->tm_sec); - formatted_time.ptr = buf; - formatted_time.len = strlen(buf); - return asn1_simple_object(type, formatted_time); -} |