--- /dev/null
+/*
+ * Copyright (c) 2017 Lev Walkin <vlm@lionet.info>.
+ * All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#include <asn_internal.h>
+#include <constr_SEQUENCE.h>
+#include <OPEN_TYPE.h>
+
+/*
+ * Number of bytes left for this structure.
+ * (ctx->left) indicates the number of bytes _transferred_ for the structure.
+ * (size) contains the number of bytes in the buffer passed.
+ */
+#define LEFT ((size<(size_t)ctx->left)?size:(size_t)ctx->left)
+
+/*
+ * If the subprocessor function returns with an indication that it wants
+ * more data, it may well be a fatal decoding problem, because the
+ * size is constrained by the <TLV>'s L, even if the buffer size allows
+ * reading more data.
+ * For example, consider the buffer containing the following TLVs:
+ * <T:5><L:1><V> <T:6>...
+ * The TLV length clearly indicates that one byte is expected in V, but
+ * if the V processor returns with "want more data" even if the buffer
+ * contains way more data than the V processor have seen.
+ */
+#define SIZE_VIOLATION (ctx->left >= 0 && (size_t)ctx->left <= size)
+
+/*
+ * This macro "eats" the part of the buffer which is definitely "consumed",
+ * i.e. was correctly converted into local representation or rightfully skipped.
+ */
+#undef ADVANCE
+#define ADVANCE(num_bytes) \
+ do { \
+ size_t num = num_bytes; \
+ ptr = ((const char *)ptr) + num; \
+ size -= num; \
+ if(ctx->left >= 0) \
+ ctx->left -= num; \
+ consumed_myself += num; \
+ } while(0)
+
+/*
+ * Switch to the next phase of parsing.
+ */
+#undef NEXT_PHASE
+#define NEXT_PHASE(ctx) \
+ do { \
+ ctx->phase++; \
+ ctx->step = 0; \
+ } while(0)
+#undef PHASE_OUT
+#define PHASE_OUT(ctx) \
+ do { \
+ ctx->phase = 10; \
+ } while(0)
+
+/*
+ * Return a standardized complex structure.
+ */
+#undef RETURN
+#define RETURN(_code) \
+ do { \
+ rval.code = _code; \
+ rval.consumed = consumed_myself; \
+ return rval; \
+ } while(0)
+
+/*
+ * Check whether we are inside the extensions group.
+ */
+#define IN_EXTENSION_GROUP(specs, memb_idx) \
+ ((specs)->first_extension >= 0 \
+ && (unsigned)(specs)->first_extension <= (memb_idx))
+
+/*
+ * Tags are canonically sorted in the tag2element map.
+ */
+static int
+_t2e_cmp(const void *ap, const void *bp) {
+ const asn_TYPE_tag2member_t *a = (const asn_TYPE_tag2member_t *)ap;
+ const asn_TYPE_tag2member_t *b = (const asn_TYPE_tag2member_t *)bp;
+
+ int a_class = BER_TAG_CLASS(a->el_tag);
+ int b_class = BER_TAG_CLASS(b->el_tag);
+
+ if(a_class == b_class) {
+ ber_tlv_tag_t a_value = BER_TAG_VALUE(a->el_tag);
+ ber_tlv_tag_t b_value = BER_TAG_VALUE(b->el_tag);
+
+ if(a_value == b_value) {
+ if(a->el_no > b->el_no)
+ return 1;
+ /*
+ * Important: we do not check
+ * for a->el_no <= b->el_no!
+ */
+ return 0;
+ } else if(a_value < b_value)
+ return -1;
+ else
+ return 1;
+ } else if(a_class < b_class) {
+ return -1;
+ } else {
+ return 1;
+ }
+}
+
+/*
+ * The decoder of the SEQUENCE type.
+ */
+asn_dec_rval_t
+SEQUENCE_decode_ber(const asn_codec_ctx_t *opt_codec_ctx,
+ const asn_TYPE_descriptor_t *td, void **struct_ptr,
+ const void *ptr, size_t size, int tag_mode) {
+ /*
+ * Bring closer parts of structure description.
+ */
+ const asn_SEQUENCE_specifics_t *specs = (const asn_SEQUENCE_specifics_t *)td->specifics;
+ const asn_TYPE_member_t *elements = td->elements;
+
+ /*
+ * Parts of the structure being constructed.
+ */
+ void *st = *struct_ptr; /* Target structure. */
+ asn_struct_ctx_t *ctx; /* Decoder context */
+
+ ber_tlv_tag_t tlv_tag; /* T from TLV */
+ asn_dec_rval_t rval; /* Return code from subparsers */
+
+ ssize_t consumed_myself = 0; /* Consumed bytes from ptr */
+ size_t edx; /* SEQUENCE element's index */
+
+ ASN_DEBUG("Decoding %s as SEQUENCE", td->name);
+
+ /*
+ * 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);
+
+ /*
+ * Start to parse where left previously
+ */
+ switch(ctx->phase) {
+ case 0:
+ /*
+ * PHASE 0.
+ * Check that the set of tags associated with given structure
+ * perfectly fits our expectations.
+ */
+
+ rval = ber_check_tags(opt_codec_ctx, td, ctx, ptr, size,
+ tag_mode, 1, &ctx->left, 0);
+ if(rval.code != RC_OK) {
+ ASN_DEBUG("%s tagging check failed: %d",
+ td->name, rval.code);
+ return rval;
+ }
+
+ if(ctx->left >= 0)
+ ctx->left += rval.consumed; /* ?Subtracted below! */
+ ADVANCE(rval.consumed);
+
+ NEXT_PHASE(ctx);
+
+ ASN_DEBUG("Structure consumes %ld bytes, buffer %ld",
+ (long)ctx->left, (long)size);
+
+ /* Fall through */
+ case 1:
+ /*
+ * PHASE 1.
+ * From the place where we've left it previously,
+ * try to decode the next member from the list of
+ * this structure's elements.
+ * (ctx->step) stores the member being processed
+ * between invocations and the microphase {0,1} of parsing
+ * that member:
+ * step = (<member_number> * 2 + <microphase>).
+ */
+ for(edx = ((size_t)ctx->step >> 1); edx < td->elements_count;
+ edx++, ctx->step = (ctx->step & ~1) + 2) {
+ void *memb_ptr; /* Pointer to the member */
+ void **memb_ptr2; /* Pointer to that pointer */
+ ssize_t tag_len; /* Length of TLV's T */
+ size_t opt_edx_end; /* Next non-optional element */
+ size_t n;
+ int use_bsearch;
+
+ if(ctx->step & 1)
+ goto microphase2;
+
+ /*
+ * MICROPHASE 1: Synchronize decoding.
+ */
+ ASN_DEBUG("In %s SEQUENCE left %d, edx=%" ASN_PRI_SIZE " flags=%d"
+ " opt=%d ec=%d",
+ td->name, (int)ctx->left, edx,
+ elements[edx].flags, elements[edx].optional,
+ td->elements_count);
+
+ if(ctx->left == 0 /* No more stuff is expected */
+ && (
+ /* Explicit OPTIONAL specification reaches the end */
+ (edx + elements[edx].optional == td->elements_count) ||
+ /* All extensions are optional */
+ IN_EXTENSION_GROUP(specs, edx))) {
+ ASN_DEBUG("End of SEQUENCE %s", td->name);
+ /*
+ * Found the legitimate end of the structure.
+ */
+ PHASE_OUT(ctx);
+ RETURN(RC_OK);
+ }
+
+ /*
+ * Fetch the T from TLV.
+ */
+ tag_len = ber_fetch_tag(ptr, LEFT, &tlv_tag);
+ ASN_DEBUG("Current tag in %s SEQUENCE for element %" ASN_PRI_SIZE " "
+ "(%s) is %s encoded in %d bytes, of frame %ld",
+ td->name, edx, elements[edx].name,
+ ber_tlv_tag_string(tlv_tag), (int)tag_len, (long)LEFT);
+ switch(tag_len) {
+ case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
+ /* Fall through */
+ case -1: RETURN(RC_FAIL);
+ }
+
+ if(ctx->left < 0 && ((const uint8_t *)ptr)[0] == 0) {
+ if(LEFT < 2) {
+ if(SIZE_VIOLATION) {
+ RETURN(RC_FAIL);
+ } else {
+ RETURN(RC_WMORE);
+ }
+ } else if(((const uint8_t *)ptr)[1] == 0) {
+ ASN_DEBUG("edx = %" ASN_PRI_SIZE ", opt = %d, ec=%d", edx,
+ elements[edx].optional, td->elements_count);
+ if((edx + elements[edx].optional == td->elements_count)
+ || IN_EXTENSION_GROUP(specs, edx)) {
+ /*
+ * Yeah, baby! Found the terminator
+ * of the indefinite length structure.
+ */
+ /*
+ * Proceed to the canonical
+ * finalization function.
+ * No advancing is necessary.
+ */
+ goto phase3;
+ }
+ }
+ }
+
+ /*
+ * Find the next available type with this tag.
+ */
+ use_bsearch = 0;
+ opt_edx_end = edx + elements[edx].optional + 1;
+ if(opt_edx_end > td->elements_count)
+ opt_edx_end = td->elements_count; /* Cap */
+ else if(opt_edx_end - edx > 8) {
+ /* Limit the scope of linear search... */
+ opt_edx_end = edx + 8;
+ use_bsearch = 1;
+ /* ... and resort to bsearch() */
+ }
+ for(n = edx; n < opt_edx_end; n++) {
+ if(BER_TAGS_EQUAL(tlv_tag, elements[n].tag)) {
+ /*
+ * Found element corresponding to the tag
+ * being looked at.
+ * Reposition over the right element.
+ */
+ edx = n;
+ ctx->step = 1 + 2 * edx; /* Remember! */
+ goto microphase2;
+ } else if(elements[n].flags & ATF_ANY_TYPE) {
+ /*
+ * This is the ANY type, which may bear
+ * any flag whatsoever.
+ */
+ edx = n;
+ ctx->step = 1 + 2 * edx; /* Remember! */
+ goto microphase2;
+ } else if(elements[n].tag == (ber_tlv_tag_t)-1) {
+ use_bsearch = 1;
+ break;
+ }
+ }
+ if(use_bsearch) {
+ /*
+ * Resort to a binary search over
+ * sorted array of tags.
+ */
+ const asn_TYPE_tag2member_t *t2m;
+ asn_TYPE_tag2member_t key = {0, 0, 0, 0};
+ key.el_tag = tlv_tag;
+ key.el_no = edx;
+ t2m = (const asn_TYPE_tag2member_t *)bsearch(&key,
+ specs->tag2el, specs->tag2el_count,
+ sizeof(specs->tag2el[0]), _t2e_cmp);
+ if(t2m) {
+ const asn_TYPE_tag2member_t *best = 0;
+ const asn_TYPE_tag2member_t *t2m_f, *t2m_l;
+ size_t edx_max = edx + elements[edx].optional;
+ /*
+ * Rewind to the first element with that tag,
+ * `cause bsearch() does not guarantee order.
+ */
+ t2m_f = t2m + t2m->toff_first;
+ t2m_l = t2m + t2m->toff_last;
+ for(t2m = t2m_f; t2m <= t2m_l; t2m++) {
+ if(t2m->el_no > edx_max) break;
+ if(t2m->el_no < edx) continue;
+ best = t2m;
+ }
+ if(best) {
+ edx = best->el_no;
+ ctx->step = 1 + 2 * edx;
+ goto microphase2;
+ }
+ }
+ n = opt_edx_end;
+ }
+ if(n == opt_edx_end) {
+ /*
+ * If tag is unknown, it may be either
+ * an unknown (thus, incorrect) tag,
+ * or an extension (...),
+ * or an end of the indefinite-length structure.
+ */
+ if(!IN_EXTENSION_GROUP(specs,
+ edx + elements[edx].optional)) {
+ ASN_DEBUG("Unexpected tag %s (at %" ASN_PRI_SIZE ")",
+ ber_tlv_tag_string(tlv_tag), edx);
+ ASN_DEBUG("Expected tag %s (%s)%s",
+ ber_tlv_tag_string(elements[edx].tag),
+ elements[edx].name,
+ elements[edx].optional ?" or alternatives":"");
+ RETURN(RC_FAIL);
+ } else {
+ /* Skip this tag */
+ ssize_t skip;
+ edx += elements[edx].optional;
+
+ ASN_DEBUG("Skipping unexpected %s (at %" ASN_PRI_SIZE ")",
+ ber_tlv_tag_string(tlv_tag), edx);
+ skip = ber_skip_length(opt_codec_ctx,
+ BER_TLV_CONSTRUCTED(ptr),
+ (const char *)ptr + tag_len,
+ LEFT - tag_len);
+ ASN_DEBUG("Skip length %d in %s",
+ (int)skip, td->name);
+ switch(skip) {
+ case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
+ /* Fall through */
+ case -1: RETURN(RC_FAIL);
+ }
+
+ ADVANCE(skip + tag_len);
+ ctx->step -= 2;
+ edx--;
+ continue; /* Try again with the next tag */
+ }
+ }
+
+ /*
+ * MICROPHASE 2: Invoke the member-specific decoder.
+ */
+ ctx->step |= 1; /* Confirm entering next microphase */
+ microphase2:
+ ASN_DEBUG("Inside SEQUENCE %s MF2", td->name);
+
+ /*
+ * Compute the position of the member inside a structure,
+ * and also a type of containment (it may be contained
+ * as pointer or using inline inclusion).
+ */
+ if(elements[edx].flags & ATF_POINTER) {
+ /* Member is a pointer to another structure */
+ memb_ptr2 = (void **)((char *)st + elements[edx].memb_offset);
+ } else {
+ /*
+ * A pointer to a pointer
+ * holding the start of the structure
+ */
+ memb_ptr = (char *)st + elements[edx].memb_offset;
+ memb_ptr2 = &memb_ptr;
+ }
+ /*
+ * Invoke the member fetch routine according to member's type
+ */
+ if(elements[edx].flags & ATF_OPEN_TYPE) {
+ rval = OPEN_TYPE_ber_get(opt_codec_ctx, td, st, &elements[edx], ptr, LEFT);
+ } else {
+ rval = elements[edx].type->op->ber_decoder(opt_codec_ctx,
+ elements[edx].type,
+ memb_ptr2, ptr, LEFT,
+ elements[edx].tag_mode);
+ }
+ ASN_DEBUG("In %s SEQUENCE decoded %" ASN_PRI_SIZE " %s of %d "
+ "in %d bytes rval.code %d, size=%d",
+ td->name, edx, elements[edx].type->name,
+ (int)LEFT, (int)rval.consumed, rval.code, (int)size);
+ switch(rval.code) {
+ case RC_OK:
+ break;
+ case RC_WMORE: /* More data expected */
+ if(!SIZE_VIOLATION) {
+ ADVANCE(rval.consumed);
+ RETURN(RC_WMORE);
+ }
+ ASN_DEBUG("Size violation (c->l=%ld <= s=%ld)",
+ (long)ctx->left, (long)size);
+ /* Fall through */
+ case RC_FAIL: /* Fatal error */
+ RETURN(RC_FAIL);
+ } /* switch(rval) */
+
+ ADVANCE(rval.consumed);
+ } /* for(all structure members) */
+
+ phase3:
+ ctx->phase = 3;
+ /* Fall through */
+ case 3: /* 00 and other tags expected */
+ case 4: /* only 00's expected */
+
+ ASN_DEBUG("SEQUENCE %s Leftover: %ld, size = %ld",
+ td->name, (long)ctx->left, (long)size);
+
+ /*
+ * Skip everything until the end of the SEQUENCE.
+ */
+ while(ctx->left) {
+ ssize_t tl, ll;
+
+ tl = ber_fetch_tag(ptr, LEFT, &tlv_tag);
+ switch(tl) {
+ case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
+ /* Fall through */
+ case -1: RETURN(RC_FAIL);
+ }
+
+ /*
+ * If expected <0><0>...
+ */
+ if(ctx->left < 0 && ((const uint8_t *)ptr)[0] == 0) {
+ if(LEFT < 2) {
+ if(SIZE_VIOLATION)
+ RETURN(RC_FAIL);
+ else
+ RETURN(RC_WMORE);
+ } else if(((const uint8_t *)ptr)[1] == 0) {
+ /*
+ * Correctly finished with <0><0>.
+ */
+ ADVANCE(2);
+ ctx->left++;
+ ctx->phase = 4;
+ continue;
+ }
+ }
+
+ if(!IN_EXTENSION_GROUP(specs, td->elements_count)
+ || ctx->phase == 4) {
+ ASN_DEBUG("Unexpected continuation "
+ "of a non-extensible type "
+ "%s (SEQUENCE): %s",
+ td->name,
+ ber_tlv_tag_string(tlv_tag));
+ RETURN(RC_FAIL);
+ }
+
+ ll = ber_skip_length(opt_codec_ctx,
+ BER_TLV_CONSTRUCTED(ptr),
+ (const char *)ptr + tl, LEFT - tl);
+ switch(ll) {
+ case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE);
+ /* Fall through */
+ case -1: RETURN(RC_FAIL);
+ }
+
+ ADVANCE(tl + ll);
+ }
+
+ PHASE_OUT(ctx);
+ }
+
+ RETURN(RC_OK);
+}
+
+
+/*
+ * The DER encoder of the SEQUENCE type.
+ */
+asn_enc_rval_t
+SEQUENCE_encode_der(const asn_TYPE_descriptor_t *td, const void *sptr,
+ 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 = {0,0,0};
+ ssize_t ret;
+ size_t 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];
+
+ const void *memb_ptr; /* Pointer to the member */
+ const void *const *memb_ptr2; /* Pointer to that pointer */
+
+ if(elm->flags & ATF_POINTER) {
+ memb_ptr2 =
+ (const void *const *)((const char *)sptr + elm->memb_offset);
+ if(!*memb_ptr2) {
+ ASN_DEBUG("Element %s %" ASN_PRI_SIZE " not present",
+ elm->name, edx);
+ if(elm->optional)
+ continue;
+ /* Mandatory element is missing */
+ ASN__ENCODE_FAILED;
+ }
+ } else {
+ memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
+ memb_ptr2 = &memb_ptr;
+ }
+
+ /* Eliminate default values */
+ if(elm->default_value_cmp && elm->default_value_cmp(*memb_ptr2) == 0)
+ continue;
+
+ erval = elm->type->op->der_encoder(elm->type, *memb_ptr2,
+ elm->tag_mode, elm->tag,
+ 0, 0);
+ if(erval.encoded == -1)
+ return erval;
+ computed_size += erval.encoded;
+ ASN_DEBUG("Member %" ASN_PRI_SIZE " %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)
+ ASN__ENCODE_FAILED;
+ erval.encoded = computed_size + ret;
+
+ if(!cb) ASN__ENCODED_OK(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 = {0,0,0};
+ const void *memb_ptr; /* Pointer to the member */
+ const void *const *memb_ptr2; /* Pointer to that pointer */
+
+ if(elm->flags & ATF_POINTER) {
+ memb_ptr2 =
+ (const void *const *)((const char *)sptr + elm->memb_offset);
+ if(!*memb_ptr2) continue;
+ } else {
+ memb_ptr = (const void *)((const char *)sptr + elm->memb_offset);
+ memb_ptr2 = &memb_ptr;
+ }
+
+ /* Eliminate default values */
+ if(elm->default_value_cmp && elm->default_value_cmp(*memb_ptr2) == 0)
+ continue;
+
+ tmperval = elm->type->op->der_encoder(elm->type, *memb_ptr2,
+ elm->tag_mode, elm->tag, cb, app_key);
+ if(tmperval.encoded == -1)
+ return tmperval;
+ computed_size -= tmperval.encoded;
+ ASN_DEBUG("Member %" ASN_PRI_SIZE " %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.
+ */
+ ASN__ENCODE_FAILED;
+
+ ASN__ENCODED_OK(erval);
+}
Code Review / sim / e2-interface.git / blobdiff