constr_sequence.c

RSA加密/解密算法源码 asn1c-0.9.12

	
	RETURN(RC_OK);
}


/*
 * The DER encoder of the SEQUENCE type.
 */
asn_enc_rval_t
SEQUENCE_encode_der(asn_TYPE_descriptor_t *td,
	void *ptr, int tag_mode, ber_tlv_tag_t tag,
	asn_app_consume_bytes_f *cb, void *app_key) {
	size_t computed_size = 0;
	asn_enc_rval_t erval;
	ssize_t ret;
	int edx;

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

	/*
	 * Gather the length of the underlying members sequence.
	 */
	for(edx = 0; edx < td->elements_count; edx++) {
		asn_TYPE_member_t *elm = &td->elements[edx];
		void *memb_ptr;
		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)ptr + elm->memb_offset);
			if(!memb_ptr) continue;
		} else {
			memb_ptr = (void *)((char *)ptr + elm->memb_offset);
		}
		erval = elm->type->der_encoder(elm->type, memb_ptr,
			elm->tag_mode, elm->tag,
			0, 0);
		if(erval.encoded == -1)
			return erval;
		computed_size += erval.encoded;
		ASN_DEBUG("Member %d %s estimated %ld bytes",
			edx, elm->name, (long)erval.encoded);
	}

	/*
	 * Encode the TLV for the sequence itself.
	 */
	ret = der_write_tags(td, computed_size, tag_mode, 1, tag, cb, app_key);
	ASN_DEBUG("Wrote tags: %ld (+%ld)", (long)ret, (long)computed_size);
	if(ret == -1) {
		erval.encoded = -1;
		erval.failed_type = td;
		erval.structure_ptr = ptr;
		return erval;
	}
	erval.encoded = computed_size + ret;

	if(!cb) return erval;

	/*
	 * Encode all members.
	 */
	for(edx = 0; edx < td->elements_count; edx++) {
		asn_TYPE_member_t *elm = &td->elements[edx];
		asn_enc_rval_t tmperval;
		void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)ptr + elm->memb_offset);
			if(!memb_ptr) continue;
		} else {
			memb_ptr = (void *)((char *)ptr + elm->memb_offset);
		}
		tmperval = elm->type->der_encoder(elm->type, memb_ptr,
			elm->tag_mode, elm->tag,
			cb, app_key);
		if(tmperval.encoded == -1)
			return tmperval;
		computed_size -= tmperval.encoded;
		ASN_DEBUG("Member %d %s of SEQUENCE %s encoded in %ld bytes",
			edx, elm->name, td->name, (long)tmperval.encoded);
	}

	if(computed_size != 0) {
		/*
		 * Encoded size is not equal to the computed size.
		 */
		erval.encoded = -1;
		erval.failed_type = td;
		erval.structure_ptr = ptr;
	}

	return erval;
}


#undef	XER_ADVANCE
#define	XER_ADVANCE(num_bytes)	do {			\
		size_t num = num_bytes;			\
		buf_ptr = ((char *)buf_ptr) + num;	\
		size -= num;				\
		consumed_myself += num;			\
	} while(0)

/*
 * Decode the XER (XML) data.
 */
asn_dec_rval_t
SEQUENCE_decode_xer(asn_codec_ctx_t *opt_codec_ctx, asn_TYPE_descriptor_t *td,
	void **struct_ptr, const char *opt_mname,
		void *buf_ptr, size_t size) {
	/*
	 * Bring closer parts of structure description.
	 */
	asn_SEQUENCE_specifics_t *specs
		= (asn_SEQUENCE_specifics_t *)td->specifics;
	asn_TYPE_member_t *elements = td->elements;
	const char *xml_tag = opt_mname ? opt_mname : td->xml_tag;

	/*
	 * ... and parts of the structure being constructed.
	 */
	void *st = *struct_ptr;	/* Target structure. */
	asn_struct_ctx_t *ctx;	/* Decoder context */

	asn_dec_rval_t rval;		/* Return value from a decoder */
	ssize_t consumed_myself = 0;	/* Consumed bytes from ptr */
	int edx;			/* Element index */
	int edx_end;

	/*
	 * Create the target structure if it is not present already.
	 */
	if(st == 0) {
		st = *struct_ptr = CALLOC(1, specs->struct_size);
		if(st == 0) RETURN(RC_FAIL);
	}

	/*
	 * Restore parsing context.
	 */
	ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);


	/*
	 * Phases of XER/XML processing:
	 * Phase 0: Check that the opening tag matches our expectations.
	 * Phase 1: Processing body and reacting on closing tag.
	 * Phase 2: Processing inner type.
	 * Phase 3: Skipping unknown extensions.
	 * Phase 4: PHASED OUT
	 */
	for(edx = ctx->step; ctx->phase <= 3;) {
		pxer_chunk_type_e ch_type;	/* XER chunk type */
		ssize_t ch_size;		/* Chunk size */
		xer_check_tag_e tcv;		/* Tag check value */
		asn_TYPE_member_t *elm;
		int n;

		/*
		 * Go inside the inner member of a sequence.
		 */
		if(ctx->phase == 2) {
			asn_dec_rval_t tmprval;
			void *memb_ptr;		/* Pointer to the member */
			void **memb_ptr2;	/* Pointer to that pointer */

			elm = &td->elements[edx];

			if(elm->flags & ATF_POINTER) {
				/* Member is a pointer to another structure */
				memb_ptr2 = (void **)((char *)st
					+ elm->memb_offset);
			} else {
				memb_ptr = (char *)st + elm->memb_offset;
				memb_ptr2 = &memb_ptr;
			}

			/* Invoke the inner type decoder, m.b. multiple times */
			tmprval = elm->type->xer_decoder(opt_codec_ctx,
					elm->type, memb_ptr2, elm->name,
					buf_ptr, size);
			XER_ADVANCE(tmprval.consumed);
			if(tmprval.code != RC_OK)
				RETURN(tmprval.code);
			ctx->phase = 1;	/* Back to body processing */
			ctx->step = ++edx;
			ASN_DEBUG("XER/SEQUENCE phase => %d, step => %d",
				ctx->phase, ctx->step);
			/* Fall through */
		}

		/*
		 * Get the next part of the XML stream.
		 */
		ch_size = xer_next_token(&ctx->context, buf_ptr, size,
			&ch_type);
		switch(ch_size) {
		case -1: RETURN(RC_FAIL);
		case 0:  RETURN(RC_WMORE);
		default:
			switch(ch_type) {
			case PXER_COMMENT:	/* Got XML comment */
			case PXER_TEXT:		/* Ignore free-standing text */
				XER_ADVANCE(ch_size);	/* Skip silently */
				continue;
			case PXER_TAG:
				break;	/* Check the rest down there */
			}
		}

		tcv = xer_check_tag(buf_ptr, ch_size, xml_tag);
		ASN_DEBUG("XER/SEQUENCE: tcv = %d, ph=%d", tcv, ctx->phase);

		/* Skip the extensions section */
		if(ctx->phase == 3) {
			switch(xer_skip_unknown(tcv, &ctx->left)) {
			case -1:
				ctx->phase = 4;
				RETURN(RC_FAIL);
			case 0:
				XER_ADVANCE(ch_size);
				continue;
			case 1:
				XER_ADVANCE(ch_size);
				ctx->phase = 1;
				continue;
			case 2:
				ctx->phase = 1;
				break;
			}
		}

		switch(tcv) {
		case XCT_CLOSING:
			if(ctx->phase == 0) break;
			ctx->phase = 0;
			/* Fall through */
		case XCT_BOTH:
			if(ctx->phase == 0) {
				if(edx >= td->elements_count
				   ||
				   /* Explicit OPTIONAL specs reaches the end */
				    (edx + elements[edx].optional
					== td->elements_count)
				   ||
				   /* All extensions are optional */
				   (IN_EXTENSION_GROUP(specs, edx)
					&& specs->ext_before
						> td->elements_count)
				) {
					XER_ADVANCE(ch_size);
					ctx->phase = 4;	/* Phase out */
					RETURN(RC_OK);
				} else {
					ASN_DEBUG("Premature end of XER SEQUENCE");
					RETURN(RC_FAIL);
				}
			}
			/* Fall through */
		case XCT_OPENING:
			if(ctx->phase == 0) {
				XER_ADVANCE(ch_size);
				ctx->phase = 1;	/* Processing body phase */
				continue;
			}
			/* Fall through */
		case XCT_UNKNOWN_OP:
		case XCT_UNKNOWN_BO:

			ASN_DEBUG("XER/SEQUENCE: tcv=%d, ph=%d",
				tcv, ctx->phase);
			if(ctx->phase != 1
			|| edx >= td->elements_count)
				break;	/* Really unexpected */

			/*
			 * Search which member corresponds to this tag.
			 */
			edx_end = edx + elements[edx].optional + 1;
			if(edx_end > td->elements_count)
				edx_end = td->elements_count;
			for(n = edx; n < edx_end; n++) {
				elm = &td->elements[n];
				tcv = xer_check_tag(buf_ptr,ch_size,elm->name);
				switch(tcv) {
				case XCT_BOTH:
				case XCT_OPENING:
					/*
					 * Process this member.
					 */
					ctx->step = edx = n;
					ctx->phase = 2;
					break;
				case XCT_UNKNOWN_OP:
				case XCT_UNKNOWN_BO:
					continue;
				default:
					n = edx_end;
					break;	/* Phase out */
				}
				break;
			}
			if(n != edx_end)
				continue;

			/* It is expected extension */
			if(IN_EXTENSION_GROUP(specs,
				edx + elements[edx].optional)) {
				ASN_DEBUG("Got anticipated extension at %d", edx);
				/*
				 * Check for (XCT_BOTH or XCT_UNKNOWN_BO)
				 * By using a mask. Only record a pure
				 * <opening> tags.
				 */
				if(tcv & XCT_CLOSING) {
					/* Found </extension> without body */
				} else {
					ctx->left = 1;
					ctx->phase = 3;	/* Skip ...'s */
				}
				XER_ADVANCE(ch_size);
				continue;
			}

			/* Fall through */
		default:
			break;
		}

		ASN_DEBUG("Unexpected XML tag in SEQUENCE");
		break;
	}

	ctx->phase = 4;	/* "Phase out" on hard failure */
	RETURN(RC_FAIL);
}

asn_enc_rval_t
SEQUENCE_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) {
	asn_enc_rval_t er;
	int xcan = (flags & XER_F_CANONICAL);
	int edx;

	if(!sptr)
		_ASN_ENCODE_FAILED;

	er.encoded = 0;

	for(edx = 0; edx < td->elements_count; edx++) {
		asn_enc_rval_t tmper;
		asn_TYPE_member_t *elm = &td->elements[edx];
		void *memb_ptr;
		const char *mname = elm->name;
		unsigned int mlen = strlen(mname);

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
			if(!memb_ptr) continue;	/* OPTIONAL element? */
		} else {
			memb_ptr = (void *)((char *)sptr + elm->memb_offset);
		}

		if(!xcan) _i_ASN_TEXT_INDENT(1, ilevel);
		_ASN_CALLBACK3("<", 1, mname, mlen, ">", 1);

		/* Print the member itself */
		tmper = elm->type->xer_encoder(elm->type, memb_ptr,
			ilevel + 1, flags, cb, app_key);
		if(tmper.encoded == -1) return tmper;

		_ASN_CALLBACK3("</", 2, mname, mlen, ">", 1);
		er.encoded += 5 + (2 * mlen) + tmper.encoded;
	}

	if(!xcan) _i_ASN_TEXT_INDENT(1, ilevel - 1);

	return er;
cb_failed:
	_ASN_ENCODE_FAILED;
}

int
SEQUENCE_print(asn_TYPE_descriptor_t *td, const void *sptr, int ilevel,
		asn_app_consume_bytes_f *cb, void *app_key) {
	int edx;
	int ret;

	if(!sptr) return (cb("<absent>", 8, app_key) < 0) ? -1 : 0;

	/* Dump preamble */
	if(cb(td->name, strlen(td->name), app_key) < 0
	|| cb(" ::= {", 6, app_key) < 0)
		return -1;

	for(edx = 0; edx < td->elements_count; edx++) {
		asn_TYPE_member_t *elm = &td->elements[edx];
		const void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
			if(!memb_ptr) continue;
		} else {
			memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
		}

		/* Indentation */
		_i_INDENT(1);

		/* Print the member's name and stuff */
		if(cb(elm->name, strlen(elm->name), app_key) < 0
		|| cb(": ", 2, app_key) < 0)
			return -1;

		/* Print the member itself */
		ret = elm->type->print_struct(elm->type, memb_ptr, ilevel + 1,
			cb, app_key);
		if(ret) return ret;
	}

	ilevel--;
	_i_INDENT(1);

	return (cb("}", 1, app_key) < 0) ? -1 : 0;
}

void
SEQUENCE_free(asn_TYPE_descriptor_t *td, void *sptr, int contents_only) {
	int edx;

	if(!td || !sptr)
		return;

	ASN_DEBUG("Freeing %s as SEQUENCE", td->name);

	for(edx = 0; edx < td->elements_count; edx++) {
		asn_TYPE_member_t *elm = &td->elements[edx];
		void *memb_ptr;
		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(void **)((char *)sptr + elm->memb_offset);
			if(memb_ptr)
				elm->type->free_struct(elm->type, memb_ptr, 0);
		} else {
			memb_ptr = (void *)((char *)sptr + elm->memb_offset);
			elm->type->free_struct(elm->type, memb_ptr, 1);
		}
	}

	if(!contents_only) {
		FREEMEM(sptr);
	}
}

int
SEQUENCE_constraint(asn_TYPE_descriptor_t *td, const void *sptr,
		asn_app_consume_bytes_f *app_errlog, void *app_key) {
	int edx;

	if(!sptr) {
		_ASN_ERRLOG(app_errlog, app_key,
			"%s: value not given (%s:%d)",
			td->name, __FILE__, __LINE__);
		return -1;
	}

	/*
	 * Iterate over structure members and check their validity.
	 */
	for(edx = 0; edx < td->elements_count; edx++) {
		asn_TYPE_member_t *elm = &td->elements[edx];
		const void *memb_ptr;

		if(elm->flags & ATF_POINTER) {
			memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset);
			if(!memb_ptr) continue;
		} else {
			memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
		}

		if(elm->memb_constraints) {
			int ret = elm->memb_constraints(elm->type, memb_ptr,
				app_errlog, app_key);
			if(ret) return ret;
		} else {
			int ret = elm->type->check_constraints(elm->type,
				memb_ptr, app_errlog, app_key);
			if(ret) return ret;
			/*
			 * Cannot inherit it earlier:
			 * need to make sure we get the updated version.
			 */
			elm->memb_constraints = elm->type->check_constraints;
		}
	}

	return 0;
}