octet_string.c

RSA加密/解密算法源码 asn1c-0.9.12

	    }
		break;
	case 3:
	phase3:
		/*
		 * Primitive form, no stack required.
		 */
		assert(ctx->left >= 0);

		if(size < (size_t)ctx->left) {
			if(!size) RETURN(RC_WMORE);
			if(type_variant == _TT_BIT_STRING && ctx->step == 0) {
				st->bits_unused = *(uint8_t *)buf_ptr;
				ctx->left--;
				ADVANCE(1);
			}
			APPEND(buf_ptr, size);
			assert(ctx->step);
			ctx->left -= size;
			ADVANCE(size);
			RETURN(RC_WMORE);
		} else {
			if(type_variant == _TT_BIT_STRING
			&& ctx->step == 0 && ctx->left) {
				st->bits_unused = *(uint8_t *)buf_ptr;
				ctx->left--;
				ADVANCE(1);
			}
			APPEND(buf_ptr, ctx->left);
			ADVANCE(ctx->left);
			ctx->left = 0;

			NEXT_PHASE(ctx);
		}
		break;
	}

	if(sel) {
		ASN_DEBUG("3sel p=%p, wn=%d, l=%ld, g=%ld, size=%ld",
			sel->prev, sel->want_nulls,
			(long)sel->left, (long)sel->got, (long)size);
		if(sel->prev || sel->want_nulls > 1 || sel->left > 0) {
			RETURN(RC_WMORE);
		}
	}

	/*
	 * BIT STRING-specific processing.
	 */
	if(type_variant == _TT_BIT_STRING && st->size) {
		/* Finalize BIT STRING: zero out unused bits. */
		st->buf[st->size-1] &= 0xff << st->bits_unused;
	}

	ASN_DEBUG("Took %ld bytes to encode %s: [%s]:%ld",
		(long)consumed_myself, td->name,
		(type_variant == _TT_GENERIC) ? (char *)st->buf : "<data>",
		(long)st->size);


	RETURN(RC_OK);
}

/*
 * Encode OCTET STRING type using DER.
 */
asn_enc_rval_t
OCTET_STRING_encode_der(asn_TYPE_descriptor_t *td, void *sptr,
	int tag_mode, ber_tlv_tag_t tag,
	asn_app_consume_bytes_f *cb, void *app_key) {
	asn_enc_rval_t er;
	asn_OCTET_STRING_specifics_t *specs = td->specifics
				? (asn_OCTET_STRING_specifics_t *)td->specifics
				: &asn_DEF_OCTET_STRING_specs;
	BIT_STRING_t *st = (BIT_STRING_t *)sptr;
	OS_type_e type_variant = (OS_type_e)specs->subvariant;
	int fix_last_byte = 0;

	ASN_DEBUG("%s %s as OCTET STRING",
		cb?"Estimating":"Encoding", td->name);

	/*
	 * Write tags.
	 */
	if(type_variant != _TT_ANY || tag_mode == 1) {
		er.encoded = der_write_tags(td,
				(type_variant == _TT_BIT_STRING) + st->size,
			tag_mode, type_variant == _TT_ANY, tag, cb, app_key);
		if(er.encoded == -1) {
			er.failed_type = td;
			er.structure_ptr = sptr;
			return er;
		}
	} else {
		/* Disallow: [<tag>] IMPLICIT ANY */
		assert(type_variant != _TT_ANY || tag_mode != -1);
		er.encoded = 0;
	}

	if(!cb) {
		er.encoded += (type_variant == _TT_BIT_STRING) + st->size;
		return er;
	}

	/*
	 * Prepare to deal with the last octet of BIT STRING.
	 */
	if(type_variant == _TT_BIT_STRING) {
		uint8_t b = st->bits_unused & 0x07;
		if(b && st->size) fix_last_byte = 1;
		_ASN_CALLBACK(&b, 1);
		er.encoded++;
	}

	/* Invoke callback for the main part of the buffer */
	_ASN_CALLBACK(st->buf, st->size - fix_last_byte);

	/* The last octet should be stripped off the unused bits */
	if(fix_last_byte) {
		uint8_t b = st->buf[st->size-1] & (0xff << st->bits_unused);
		_ASN_CALLBACK(&b, 1);
	}

	er.encoded += st->size;
	return er;
cb_failed:
	_ASN_ENCODE_FAILED;
}

asn_enc_rval_t
OCTET_STRING_encode_xer(asn_TYPE_descriptor_t *td, void *sptr,
	int ilevel, enum xer_encoder_flags_e flags,
		asn_app_consume_bytes_f *cb, void *app_key) {
	static const char *h2c = "0123456789ABCDEF";
	const OCTET_STRING_t *st = (const OCTET_STRING_t *)sptr;
	asn_enc_rval_t er;
	char scratch[16 * 3 + 4];
	char *p = scratch;
	uint8_t *buf;
	uint8_t *end;
	size_t i;

	if(!st || !st->buf)
		_ASN_ENCODE_FAILED;

	er.encoded = 0;

	/*
	 * Dump the contents of the buffer in hexadecimal.
	 */
	buf = st->buf;
	end = buf + st->size;
	if(flags & XER_F_CANONICAL) {
		char *scend = scratch + (sizeof(scratch) - 2);
		for(; buf < end; buf++) {
			if(p >= scend) {
				_ASN_CALLBACK(scratch, p - scratch);
				er.encoded += p - scratch;
				p = scratch;
			}
			*p++ = h2c[(*buf >> 4) & 0x0F];
			*p++ = h2c[*buf & 0x0F];
		}

		_ASN_CALLBACK(scratch, p-scratch);	/* Dump the rest */
		er.encoded += p - scratch;
	} else {
		for(i = 0; buf < end; buf++, i++) {
			if(!(i % 16) && (i || st->size > 16)) {
				_ASN_CALLBACK(scratch, p-scratch);
				er.encoded += (p-scratch);
				p = scratch;
				_i_ASN_TEXT_INDENT(1, ilevel);
			}
			*p++ = h2c[(*buf >> 4) & 0x0F];
			*p++ = h2c[*buf & 0x0F];
			*p++ = 0x20;
		}
		if(p - scratch) {
			p--;	/* Remove the tail space */
			_ASN_CALLBACK(scratch, p-scratch); /* Dump the rest */
			er.encoded += p - scratch;
			if(st->size > 16)
				_i_ASN_TEXT_INDENT(1, ilevel-1);
		}
	}

	return er;
cb_failed:
	_ASN_ENCODE_FAILED;
}

static struct OCTET_STRING__xer_escape_table_s {
	char *string;
	int size;
} OCTET_STRING__xer_escape_table[] = {
#define	OSXET(s)	{ s, sizeof(s) - 1 }
	OSXET("\074\156\165\154\057\076"),	/* <nul/> */
	OSXET("\074\163\157\150\057\076"),	/* <soh/> */
	OSXET("\074\163\164\170\057\076"),	/* <stx/> */
	OSXET("\074\145\164\170\057\076"),	/* <etx/> */
	OSXET("\074\145\157\164\057\076"),	/* <eot/> */
	OSXET("\074\145\156\161\057\076"),	/* <enq/> */
	OSXET("\074\141\143\153\057\076"),	/* <ack/> */
	OSXET("\074\142\145\154\057\076"),	/* <bel/> */
	OSXET("\074\142\163\057\076"),		/* <bs/> */
	OSXET("\011"),				/* \t */
	OSXET("\012"),				/* \n */
	OSXET("\074\166\164\057\076"),		/* <vt/> */
	OSXET("\074\146\146\057\076"),		/* <ff/> */
	OSXET("\015"),				/* \r */
	OSXET("\074\163\157\057\076"),		/* <so/> */
	OSXET("\074\163\151\057\076"),		/* <si/> */
	OSXET("\074\144\154\145\057\076"),	/* <dle/> */
	OSXET("\074\144\143\061\057\076"),	/* <de1/> */
	OSXET("\074\144\143\062\057\076"),	/* <de2/> */
	OSXET("\074\144\143\063\057\076"),	/* <de3/> */
	OSXET("\074\144\143\064\057\076"),	/* <de4/> */
	OSXET("\074\156\141\153\057\076"),	/* <nak/> */
	OSXET("\074\163\171\156\057\076"),	/* <syn/> */
	OSXET("\074\145\164\142\057\076"),	/* <etb/> */
	OSXET("\074\143\141\156\057\076"),	/* <can/> */
	OSXET("\074\145\155\057\076"),		/* <em/> */
	OSXET("\074\163\165\142\057\076"),	/* <sub/> */
	OSXET("\074\145\163\143\057\076"),	/* <esc/> */
	OSXET("\074\151\163\064\057\076"),	/* <is4/> */
	OSXET("\074\151\163\063\057\076"),	/* <is3/> */
	OSXET("\074\151\163\062\057\076"),	/* <is2/> */
	OSXET("\074\151\163\061\057\076"),	/* <is1/> */
	{ 0, 0 },	/* " " */
	{ 0, 0 },	/* ! */
	{ 0, 0 },	/* \" */
	{ 0, 0 },	/* # */
	{ 0, 0 },	/* $ */
	{ 0, 0 },	/* % */
	OSXET("\046\141\155\160\073"),	/* &amp; */
	{ 0, 0 },	/* ' */
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, /* ()*+,-./ */
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}, /* 01234567 */
	{0,0},{0,0},{0,0},{0,0},			 /* 89:; */
	OSXET("\046\154\164\073"),	/* &lt; */
	{ 0, 0 },	/* = */
	OSXET("\046\147\164\073"),	/* &gt; */
};

static int
OS__check_escaped_control_char(const void *buf, int size) {
	size_t i;
	/*
	 * Inefficient algorithm which translates the escape sequences
	 * defined above into characters. Returns -1 if not found.
	 * TODO: replace by a faster algorithm (bsearch(), hash or
	 * nested table lookups).
	 */
	for(i = 0; i < 32 /* Don't spend time on the bottom half */; i++) {
		struct OCTET_STRING__xer_escape_table_s *el;
		el = &OCTET_STRING__xer_escape_table[i];
		if(el->size == size && memcmp(buf, el->string, size) == 0)
			return i;
	}
	return -1;
}

static int
OCTET_STRING__handle_control_chars(void *struct_ptr, const void *chunk_buf, size_t chunk_size) {
	/*
	 * This might be one of the escape sequences
	 * for control characters. Check it out.
	 * #11.15.5
	 */
	int control_char = OS__check_escaped_control_char(chunk_buf,chunk_size);
	if(control_char >= 0) {
		OCTET_STRING_t *st = (OCTET_STRING_t *)struct_ptr;
		void *p = REALLOC(st->buf, st->size + 2);
		if(p) {
			st->buf = (uint8_t *)p;
			st->buf[st->size++] = control_char;
			st->buf[st->size] = '\0';	/* nul-termination */
			return 0;
		}
	}
	
	return -1;	/* No, it's not */
}

asn_enc_rval_t
OCTET_STRING_encode_xer_utf8(asn_TYPE_descriptor_t *td, void *sptr,
	int ilevel, enum xer_encoder_flags_e flags,
		asn_app_consume_bytes_f *cb, void *app_key) {
	const OCTET_STRING_t *st = (const OCTET_STRING_t *)sptr;
	asn_enc_rval_t er;
	uint8_t *buf, *end;
	uint8_t *ss;	/* Sequence start */
	ssize_t encoded_len = 0;

	(void)ilevel;	/* Unused argument */
	(void)flags;	/* Unused argument */

	if(!st || !st->buf)
		_ASN_ENCODE_FAILED;

	buf = st->buf;
	end = buf + st->size;
	for(ss = buf; buf < end; buf++) {
		unsigned int ch = *buf;
		int s_len;	/* Special encoding sequence length */

		/*
		 * Escape certain characters: X.680/11.15
		 */
		if(ch < sizeof(OCTET_STRING__xer_escape_table)
			/sizeof(OCTET_STRING__xer_escape_table[0])
		&& (s_len = OCTET_STRING__xer_escape_table[ch].size)) {
			if(((buf - ss) && cb(ss, buf - ss, app_key) < 0)
			|| cb(OCTET_STRING__xer_escape_table[ch].string, s_len,
					app_key) < 0)
				_ASN_ENCODE_FAILED;
			encoded_len += (buf - ss) + s_len;
			ss = buf + 1;
		}
	}

	encoded_len += (buf - ss);
	if((buf - ss) && cb(ss, buf - ss, app_key) < 0)
		_ASN_ENCODE_FAILED;

	er.encoded = encoded_len;
	return er;
}

/*
 * Convert from hexadecimal format (cstring): "AB CD EF"
 */
static ssize_t OCTET_STRING__convert_hexadecimal(void *sptr, const void *chunk_buf, size_t chunk_size, int have_more) {
	OCTET_STRING_t *st = (OCTET_STRING_t *)sptr;
	const char *chunk_stop = (const char *)chunk_buf;
	const char *p = chunk_stop;
	const char *pend = p + chunk_size;
	unsigned int clv = 0;
	int half = 0;	/* Half bit */
	uint8_t *buf;

	/* Reallocate buffer according to high cap estimation */
	ssize_t _ns = st->size + (chunk_size + 1) / 2;
	void *nptr = REALLOC(st->buf, _ns + 1);
	if(!nptr) return -1;
	st->buf = (uint8_t *)nptr;
	buf = st->buf + st->size;

	/*
	 * If something like " a b c " appears here, the " a b":3 will be
	 * converted, and the rest skipped. That is, unless buf_size is greater
	 * than chunk_size, then it'll be equivalent to "ABC0".
	 */
	for(; p < pend; p++) {
		int ch = *(const unsigned char *)p;
		switch(ch) {
		case 0x09: case 0x0a: case 0x0c: case 0x0d:
		case 0x20:
			/* Ignore whitespace */
			continue;
		case 0x30: case 0x31: case 0x32: case 0x33: case 0x34: /*01234*/
		case 0x35: case 0x36: case 0x37: case 0x38: case 0x39: /*56789*/
			clv = (clv << 4) + (ch - 0x30);
			break;
		case 0x41: case 0x42: case 0x43:	/* ABC */
		case 0x44: case 0x45: case 0x46:	/* DEF */
			clv = (clv << 4) + (ch - 0x41 + 10);
			break;
		case 0x61: case 0x62: case 0x63:	/* abc */
		case 0x64: case 0x65: case 0x66:	/* def */
			clv = (clv << 4) + (ch - 0x61 + 10);
			break;
		default:
			*buf = 0;	/* JIC */
			return -1;
		}
		if(half++) {
			half = 0;
			*buf++ = clv;
			chunk_stop = p + 1;
		}
	}

	/*
	 * Check partial decoding.
	 */
	if(half) {
		if(have_more) {
			/*
			 * Partial specification is fine,
			 * because no more more PXER_TEXT data is available.
			 */
			*buf++ = clv << 4;
			chunk_stop = p;
		}
	} else {
		chunk_stop = p;
	}

	st->size = buf - st->buf;	/* Adjust the buffer size */
	assert(st->size <= _ns);
	st->buf[st->size] = 0;		/* Courtesy termination */

	return (chunk_stop - (const char *)chunk_buf);	/* Converted size */
}

/*
 * Convert from binary format: "00101011101"
 */
static ssize_t OCTET_STRING__convert_binary(void *sptr, const void *chunk_buf, size_t chunk_size, int have_more) {
	BIT_STRING_t *st = (BIT_STRING_t *)sptr;
	const char *p = (const char *)chunk_buf;
	const char *pend = p + chunk_size;
	int bits_unused = st->bits_unused & 0x7;
	uint8_t *buf;

	/* Reallocate buffer according to high cap estimation */
	ssize_t _ns = st->size + (chunk_size + 7) / 8;
	void *nptr = REALLOC(st->buf, _ns + 1);
	if(!nptr) return -1;
	st->buf = (uint8_t *)nptr;
	buf = st->buf + st->size;

	(void)have_more;

	if(bits_unused == 0)
		bits_unused = 8;
	else if(st->size)
		buf--;

	/*
	 * Convert series of 0 and 1 into the octet string.
	 */
	for(; p < pend; p++) {
		int ch = *(const unsigned char *)p;
		switch(ch) {
		case 0x09: case 0x0a: case 0x0c: case 0x0d:
		case 0x20:
			/* Ignore whitespace */
			break;
		case 0x30:
		case 0x31:
			if(bits_unused-- <= 0) {
				*++buf = 0;	/* Clean the cell */
				bits_unused = 7;
			}