+++ /dev/null
-/*-
- * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved.
- * Redistribution and modifications are permitted subject to BSD license.
- */
-#include <asn_internal.h>
-#include <errno.h>
-
-static ssize_t der_write_TL(ber_tlv_tag_t tag, ber_tlv_len_t len,
- asn_app_consume_bytes_f *cb, void *app_key, int constructed);
-
-/*
- * The DER encoder of any type.
- */
-asn_enc_rval_t
-der_encode(asn_TYPE_descriptor_t *type_descriptor, void *struct_ptr,
- asn_app_consume_bytes_f *consume_bytes, void *app_key) {
-
- ASN_DEBUG("DER encoder invoked for %s",
- type_descriptor->name);
-
- /*
- * Invoke type-specific encoder.
- */
- return type_descriptor->der_encoder(type_descriptor,
- struct_ptr, /* Pointer to the destination structure */
- 0, 0,
- consume_bytes, app_key);
-}
-
-/*
- * Argument type and callback necessary for der_encode_to_buffer().
- */
-typedef struct enc_to_buf_arg {
- void *buffer;
- size_t left;
-} enc_to_buf_arg;
-static int encode_to_buffer_cb(const void *buffer, size_t size, void *key) {
- enc_to_buf_arg *arg = (enc_to_buf_arg *)key;
-
- if(arg->left < size)
- return -1; /* Data exceeds the available buffer size */
-
- memcpy(arg->buffer, buffer, size);
- arg->buffer = ((char *)arg->buffer) + size;
- arg->left -= size;
-
- return 0;
-}
-
-/*
- * A variant of the der_encode() which encodes the data into the provided buffer
- */
-asn_enc_rval_t
-der_encode_to_buffer(asn_TYPE_descriptor_t *type_descriptor, void *struct_ptr,
- void *buffer, size_t buffer_size) {
- enc_to_buf_arg arg;
- asn_enc_rval_t ec;
-
- arg.buffer = buffer;
- arg.left = buffer_size;
-
- ec = type_descriptor->der_encoder(type_descriptor,
- struct_ptr, /* Pointer to the destination structure */
- 0, 0, encode_to_buffer_cb, &arg);
- if(ec.encoded != -1) {
- assert(ec.encoded == (ssize_t)(buffer_size - arg.left));
- /* Return the encoded contents size */
- }
- return ec;
-}
-
-
-/*
- * Write out leading TL[v] sequence according to the type definition.
- */
-ssize_t
-der_write_tags(asn_TYPE_descriptor_t *sd,
- size_t struct_length,
- int tag_mode, int last_tag_form,
- ber_tlv_tag_t tag, /* EXPLICIT or IMPLICIT tag */
- asn_app_consume_bytes_f *cb,
- void *app_key) {
- ber_tlv_tag_t *tags; /* Copy of tags stream */
- int tags_count; /* Number of tags */
- size_t overall_length;
- ssize_t *lens;
- int i;
-
- ASN_DEBUG("Writing tags (%s, tm=%d, tc=%d, tag=%s, mtc=%d)",
- sd->name, tag_mode, sd->tags_count,
- ber_tlv_tag_string(tag),
- tag_mode
- ?(sd->tags_count+1
- -((tag_mode == -1) && sd->tags_count))
- :sd->tags_count
- );
-
- if(tag_mode) {
- /*
- * Instead of doing shaman dance like we do in ber_check_tags(),
- * allocate a small array on the stack
- * and initialize it appropriately.
- */
- int stag_offset;
- tags = (ber_tlv_tag_t *)alloca((sd->tags_count + 1) * sizeof(ber_tlv_tag_t));
- if(!tags) { /* Can fail on !x86 */
- errno = ENOMEM;
- return -1;
- }
- tags_count = sd->tags_count
- + 1 /* EXPLICIT or IMPLICIT tag is given */
- - ((tag_mode == -1) && sd->tags_count);
- /* Copy tags over */
- tags[0] = tag;
- stag_offset = -1 + ((tag_mode == -1) && sd->tags_count);
- for(i = 1; i < tags_count; i++)
- tags[i] = sd->tags[i + stag_offset];
- } else {
- tags = sd->tags;
- tags_count = sd->tags_count;
- }
-
- /* No tags to write */
- if(tags_count == 0)
- return 0;
-
- lens = (ssize_t *)alloca(tags_count * sizeof(lens[0]));
- if(!lens) {
- errno = ENOMEM;
- return -1;
- }
-
- /*
- * Array of tags is initialized.
- * Now, compute the size of the TLV pairs, from right to left.
- */
- overall_length = struct_length;
- for(i = tags_count - 1; i >= 0; --i) {
- lens[i] = der_write_TL(tags[i], overall_length, 0, 0, 0);
- if(lens[i] == -1) return -1;
- overall_length += lens[i];
- lens[i] = overall_length - lens[i];
- }
-
- if(!cb) return overall_length - struct_length;
-
- ASN_DEBUG("%s %s TL sequence (%d elements)",
- cb?"Encoding":"Estimating", sd->name, tags_count);
-
- /*
- * Encode the TL sequence for real.
- */
- for(i = 0; i < tags_count; i++) {
- ssize_t len;
- int _constr;
-
- /* Check if this tag happens to be constructed */
- _constr = (last_tag_form || i < (tags_count - 1));
-
- len = der_write_TL(tags[i], lens[i], cb, app_key, _constr);
- if(len == -1) return -1;
- }
-
- return overall_length - struct_length;
-}
-
-static ssize_t
-der_write_TL(ber_tlv_tag_t tag, ber_tlv_len_t len,
- asn_app_consume_bytes_f *cb, void *app_key,
- int constructed) {
- uint8_t buf[32];
- size_t size = 0;
- int buf_size = cb?sizeof(buf):0;
- ssize_t tmp;
-
- /* Serialize tag (T from TLV) into possibly zero-length buffer */
- tmp = ber_tlv_tag_serialize(tag, buf, buf_size);
- if(tmp == -1 || tmp > (ssize_t)sizeof(buf)) return -1;
- size += tmp;
-
- /* Serialize length (L from TLV) into possibly zero-length buffer */
- tmp = der_tlv_length_serialize(len, buf+size, buf_size?buf_size-size:0);
- if(tmp == -1) return -1;
- size += tmp;
-
- if(size > sizeof(buf))
- return -1;
-
- /*
- * If callback is specified, invoke it, and check its return value.
- */
- if(cb) {
- if(constructed) *buf |= 0x20;
- if(cb(buf, size, app_key) < 0)
- return -1;
- }
-
- return size;
-}