--- /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 <OCTET_STRING.h>
+#include <BIT_STRING.h> /* for .bits_unused member */
+
+#undef _CH_PHASE
+#define _CH_PHASE(ctx, inc) do {\
+ if(ctx->phase == 0)\
+ ctx->context = 0;\
+ ctx->phase += inc;\
+ } while(0)
+
+#undef NEXT_PHASE
+#define NEXT_PHASE(ctx) _CH_PHASE(ctx, +1)
+#undef PREV_PHASE
+#define PREV_PHASE(ctx) _CH_PHASE(ctx, -1)
+
+#undef ADVANCE
+#define ADVANCE(num_bytes) do {\
+ size_t num = (num_bytes);\
+ buf_ptr = ((const char *)buf_ptr) + num;\
+ size -= num;\
+ consumed_myself += num;\
+ } while(0)
+
+#undef RETURN
+#define RETURN(_code) do {\
+ asn_dec_rval_t tmprval;\
+ tmprval.code = _code;\
+ tmprval.consumed = consumed_myself;\
+ return tmprval;\
+ } while(0)
+
+#undef APPEND
+#define APPEND(bufptr, bufsize) do {\
+ size_t _bs = (bufsize); /* Append size */\
+ size_t _ns = ctx->context; /* Allocated now */\
+ size_t _es = st->size + _bs; /* Expected size */\
+ /* int is really a typeof(st->size): */\
+ if((int)_es < 0) RETURN(RC_FAIL);\
+ if(_ns <= _es) {\
+ void *ptr;\
+ /* Be nice and round to the memory allocator */\
+ do { _ns = _ns ? _ns << 1 : 16; }\
+ while(_ns <= _es);\
+ /* int is really a typeof(st->size): */\
+ if((int)_ns < 0) RETURN(RC_FAIL);\
+ ptr = REALLOC(st->buf, _ns);\
+ if(ptr) {\
+ st->buf = (uint8_t *)ptr;\
+ ctx->context = _ns;\
+ } else {\
+ RETURN(RC_FAIL);\
+ }\
+ ASN_DEBUG("Reallocating into %ld", (long)_ns);\
+ }\
+ memcpy(st->buf + st->size, bufptr, _bs);\
+ /* Convenient nul-termination */\
+ st->buf[_es] = '\0';\
+ st->size = _es;\
+ } while(0)
+
+/*
+ * The main reason why ASN.1 is still alive is that too much time and effort
+ * is necessary for learning it more or less adequately, thus creating a gut
+ * necessity to demonstrate that acquired skill everywhere afterwards.
+ * No, I am not going to explain what the following stuff is.
+ */
+static struct _stack_el *
+OS__add_stack_el(struct _stack *st) {
+ struct _stack_el *nel;
+
+ /*
+ * Reuse the old stack frame or allocate a new one.
+ */
+ if(st->cur_ptr && st->cur_ptr->next) {
+ nel = st->cur_ptr->next;
+ nel->bits_chopped = 0;
+ nel->got = 0;
+ /* Retain the nel->cont_level, it's correct. */
+ } else {
+ nel = (struct _stack_el *)CALLOC(1, sizeof(struct _stack_el));
+ if(nel == NULL)
+ return NULL;
+
+ if(st->tail) {
+ /* Increase a subcontainment depth */
+ nel->cont_level = st->tail->cont_level + 1;
+ st->tail->next = nel;
+ }
+ nel->prev = st->tail;
+ st->tail = nel;
+ }
+
+ st->cur_ptr = nel;
+
+ return nel;
+}
+
+static struct _stack *
+_new_stack(void) {
+ return (struct _stack *)CALLOC(1, sizeof(struct _stack));
+}
+
+/*
+ * Decode OCTET STRING type.
+ */
+asn_dec_rval_t
+OCTET_STRING_decode_ber(const asn_codec_ctx_t *opt_codec_ctx,
+ const asn_TYPE_descriptor_t *td, void **sptr,
+ const void *buf_ptr, size_t size, int tag_mode) {
+ const asn_OCTET_STRING_specifics_t *specs = td->specifics
+ ? (const asn_OCTET_STRING_specifics_t *)td->specifics
+ : &asn_SPC_OCTET_STRING_specs;
+ BIT_STRING_t *st = (BIT_STRING_t *)*sptr;
+ asn_dec_rval_t rval;
+ asn_struct_ctx_t *ctx;
+ ssize_t consumed_myself = 0;
+ struct _stack *stck; /* Expectations stack structure */
+ struct _stack_el *sel = 0; /* Stack element */
+ int tlv_constr;
+ enum asn_OS_Subvariant type_variant = specs->subvariant;
+
+ ASN_DEBUG("Decoding %s as %s (frame %ld)",
+ td->name,
+ (type_variant == ASN_OSUBV_STR) ?
+ "OCTET STRING" : "OS-SpecialCase",
+ (long)size);
+
+ /*
+ * Create the string if does not exist.
+ */
+ if(st == NULL) {
+ st = (BIT_STRING_t *)(*sptr = CALLOC(1, specs->struct_size));
+ if(st == NULL) RETURN(RC_FAIL);
+ }
+
+ /* Restore parsing context */
+ ctx = (asn_struct_ctx_t *)((char *)st + specs->ctx_offset);
+
+ switch(ctx->phase) {
+ case 0:
+ /*
+ * Check tags.
+ */
+ rval = ber_check_tags(opt_codec_ctx, td, ctx,
+ buf_ptr, size, tag_mode, -1,
+ &ctx->left, &tlv_constr);
+ if(rval.code != RC_OK)
+ return rval;
+
+ if(tlv_constr) {
+ /*
+ * Complex operation, requires stack of expectations.
+ */
+ ctx->ptr = _new_stack();
+ if(!ctx->ptr) {
+ RETURN(RC_FAIL);
+ }
+ } else {
+ /*
+ * Jump into stackless primitive decoding.
+ */
+ _CH_PHASE(ctx, 3);
+ if(type_variant == ASN_OSUBV_ANY && tag_mode != 1)
+ APPEND(buf_ptr, rval.consumed);
+ ADVANCE(rval.consumed);
+ goto phase3;
+ }
+
+ NEXT_PHASE(ctx);
+ /* Fall through */
+ case 1:
+ phase1:
+ /*
+ * Fill the stack with expectations.
+ */
+ stck = (struct _stack *)ctx->ptr;
+ sel = stck->cur_ptr;
+ do {
+ ber_tlv_tag_t tlv_tag;
+ ber_tlv_len_t tlv_len;
+ ber_tlv_tag_t expected_tag;
+ ssize_t tl, ll, tlvl;
+ /* This one works even if (sel->left == -1) */
+ size_t Left = ((!sel||(size_t)sel->left >= size)
+ ?size:(size_t)sel->left);
+
+
+ ASN_DEBUG("%p, s->l=%ld, s->wn=%ld, s->g=%ld\n", (void *)sel,
+ (long)(sel?sel->left:0),
+ (long)(sel?sel->want_nulls:0),
+ (long)(sel?sel->got:0)
+ );
+ if(sel && sel->left <= 0 && sel->want_nulls == 0) {
+ if(sel->prev) {
+ struct _stack_el *prev = sel->prev;
+ if(prev->left != -1) {
+ if(prev->left < sel->got)
+ RETURN(RC_FAIL);
+ prev->left -= sel->got;
+ }
+ prev->got += sel->got;
+ sel = stck->cur_ptr = prev;
+ if(!sel) break;
+ tlv_constr = 1;
+ continue;
+ } else {
+ sel = stck->cur_ptr = 0;
+ break; /* Nothing to wait */
+ }
+ }
+
+ tl = ber_fetch_tag(buf_ptr, Left, &tlv_tag);
+ ASN_DEBUG("fetch tag(size=%ld,L=%ld), %sstack, left=%ld, wn=%ld, tl=%ld",
+ (long)size, (long)Left, sel?"":"!",
+ (long)(sel?sel->left:0),
+ (long)(sel?sel->want_nulls:0),
+ (long)tl);
+ switch(tl) {
+ case -1: RETURN(RC_FAIL);
+ case 0: RETURN(RC_WMORE);
+ }
+
+ tlv_constr = BER_TLV_CONSTRUCTED(buf_ptr);
+
+ ll = ber_fetch_length(tlv_constr,
+ (const char *)buf_ptr + tl,Left - tl,&tlv_len);
+ ASN_DEBUG("Got tag=%s, tc=%d, left=%ld, tl=%ld, len=%ld, ll=%ld",
+ ber_tlv_tag_string(tlv_tag), tlv_constr,
+ (long)Left, (long)tl, (long)tlv_len, (long)ll);
+ switch(ll) {
+ case -1: RETURN(RC_FAIL);
+ case 0: RETURN(RC_WMORE);
+ }
+
+ if(sel && sel->want_nulls
+ && ((const uint8_t *)buf_ptr)[0] == 0
+ && ((const uint8_t *)buf_ptr)[1] == 0)
+ {
+ ASN_DEBUG("Eat EOC; wn=%d--", sel->want_nulls);
+
+ if(type_variant == ASN_OSUBV_ANY
+ && (tag_mode != 1 || sel->cont_level))
+ APPEND("\0\0", 2);
+
+ ADVANCE(2);
+ sel->got += 2;
+ if(sel->left != -1) {
+ sel->left -= 2; /* assert(sel->left >= 2) */
+ }
+
+ sel->want_nulls--;
+ if(sel->want_nulls == 0) {
+ /* Move to the next expectation */
+ sel->left = 0;
+ tlv_constr = 1;
+ }
+
+ continue;
+ }
+
+ /*
+ * Set up expected tags,
+ * depending on ASN.1 type being decoded.
+ */
+ switch(type_variant) {
+ case ASN_OSUBV_BIT:
+ /* X.690: 8.6.4.1, NOTE 2 */
+ /* Fall through */
+ case ASN_OSUBV_STR:
+ default:
+ if(sel) {
+ unsigned level = sel->cont_level;
+ if(level < td->all_tags_count) {
+ expected_tag = td->all_tags[level];
+ break;
+ } else if(td->all_tags_count) {
+ expected_tag = td->all_tags
+ [td->all_tags_count - 1];
+ break;
+ }
+ /* else, Fall through */
+ }
+ /* Fall through */
+ case ASN_OSUBV_ANY:
+ expected_tag = tlv_tag;
+ break;
+ }
+
+ if(tlv_tag != expected_tag) {
+ char buf[2][32];
+ ber_tlv_tag_snprint(tlv_tag,
+ buf[0], sizeof(buf[0]));
+ ber_tlv_tag_snprint(td->tags[td->tags_count-1],
+ buf[1], sizeof(buf[1]));
+ ASN_DEBUG("Tag does not match expectation: %s != %s",
+ buf[0], buf[1]);
+ RETURN(RC_FAIL);
+ }
+
+ tlvl = tl + ll; /* Combined length of T and L encoding */
+ if((tlv_len + tlvl) < 0) {
+ /* tlv_len value is too big */
+ ASN_DEBUG("TLV encoding + length (%ld) is too big",
+ (long)tlv_len);
+ RETURN(RC_FAIL);
+ }
+
+ /*
+ * Append a new expectation.
+ */
+ sel = OS__add_stack_el(stck);
+ if(!sel) RETURN(RC_FAIL);
+
+ sel->tag = tlv_tag;
+
+ sel->want_nulls = (tlv_len==-1);
+ if(sel->prev && sel->prev->left != -1) {
+ /* Check that the parent frame is big enough */
+ if(sel->prev->left < tlvl + (tlv_len==-1?0:tlv_len))
+ RETURN(RC_FAIL);
+ if(tlv_len == -1)
+ sel->left = sel->prev->left - tlvl;
+ else
+ sel->left = tlv_len;
+ } else {
+ sel->left = tlv_len;
+ }
+ if(type_variant == ASN_OSUBV_ANY
+ && (tag_mode != 1 || sel->cont_level))
+ APPEND(buf_ptr, tlvl);
+ sel->got += tlvl;
+ ADVANCE(tlvl);
+
+ ASN_DEBUG("+EXPECT2 got=%ld left=%ld, wn=%d, clvl=%u",
+ (long)sel->got, (long)sel->left,
+ sel->want_nulls, sel->cont_level);
+
+ } while(tlv_constr);
+ if(sel == NULL) {
+ /* Finished operation, "phase out" */
+ ASN_DEBUG("Phase out");
+ _CH_PHASE(ctx, +3);
+ break;
+ }
+
+ NEXT_PHASE(ctx);
+ /* Fall through */
+ case 2:
+ stck = (struct _stack *)ctx->ptr;
+ sel = stck->cur_ptr;
+ ASN_DEBUG("Phase 2: Need %ld bytes, size=%ld, alrg=%ld, wn=%d",
+ (long)sel->left, (long)size, (long)sel->got,
+ sel->want_nulls);
+ {
+ ber_tlv_len_t len;
+
+ assert(sel->left >= 0);
+
+ len = ((ber_tlv_len_t)size < sel->left)
+ ? (ber_tlv_len_t)size : sel->left;
+ if(len > 0) {
+ if(type_variant == ASN_OSUBV_BIT
+ && sel->bits_chopped == 0) {
+ /* Put the unused-bits-octet away */
+ st->bits_unused = *(const uint8_t *)buf_ptr;
+ APPEND(((const char *)buf_ptr+1), (len - 1));
+ sel->bits_chopped = 1;
+ } else {
+ APPEND(buf_ptr, len);
+ }
+ ADVANCE(len);
+ sel->left -= len;
+ sel->got += len;
+ }
+
+ if(sel->left) {
+ ASN_DEBUG("OS left %ld, size = %ld, wn=%d\n",
+ (long)sel->left, (long)size, sel->want_nulls);
+ RETURN(RC_WMORE);
+ }
+
+ PREV_PHASE(ctx);
+ goto phase1;
+ }
+ 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 == ASN_OSUBV_BIT && !ctx->context) {
+ st->bits_unused = *(const uint8_t *)buf_ptr;
+ ctx->left--;
+ ADVANCE(1);
+ }
+ APPEND(buf_ptr, size);
+ assert(ctx->context > 0);
+ ctx->left -= size;
+ ADVANCE(size);
+ RETURN(RC_WMORE);
+ } else {
+ if(type_variant == ASN_OSUBV_BIT
+ && !ctx->context && ctx->left) {
+ st->bits_unused = *(const 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",
+ (void *)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 == ASN_OSUBV_BIT) {
+ if(st->size) {
+ if(st->bits_unused < 0 || st->bits_unused > 7) {
+ RETURN(RC_FAIL);
+ }
+ /* Finalize BIT STRING: zero out unused bits. */
+ st->buf[st->size-1] &= 0xff << st->bits_unused;
+ } else {
+ if(st->bits_unused) {
+ RETURN(RC_FAIL);
+ }
+ }
+ }
+
+ ASN_DEBUG("Took %ld bytes to encode %s: [%s]:%ld",
+ (long)consumed_myself, td->name,
+ (type_variant == ASN_OSUBV_STR) ? (char *)st->buf : "<data>",
+ (long)st->size);
+
+
+ RETURN(RC_OK);
+}
+
+/*
+ * Encode OCTET STRING type using DER.
+ */
+asn_enc_rval_t
+OCTET_STRING_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) {
+ asn_enc_rval_t er = { 0, 0, 0 };
+ const asn_OCTET_STRING_specifics_t *specs = td->specifics
+ ? (const asn_OCTET_STRING_specifics_t *)td->specifics
+ : &asn_SPC_OCTET_STRING_specs;
+ const BIT_STRING_t *st = (const BIT_STRING_t *)sptr;
+ enum asn_OS_Subvariant type_variant = specs->subvariant;
+ int fix_last_byte = 0;
+
+ ASN_DEBUG("%s %s as OCTET STRING",
+ cb?"Estimating":"Encoding", td->name);
+
+ /*
+ * Write tags.
+ */
+ if(type_variant != ASN_OSUBV_ANY || tag_mode == 1) {
+ er.encoded = der_write_tags(td,
+ (type_variant == ASN_OSUBV_BIT) + st->size,
+ tag_mode, type_variant == ASN_OSUBV_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 != ASN_OSUBV_ANY || tag_mode != -1);
+ er.encoded = 0;
+ }
+
+ if(!cb) {
+ er.encoded += (type_variant == ASN_OSUBV_BIT) + st->size;
+ ASN__ENCODED_OK(er);
+ }
+
+ /*
+ * Prepare to deal with the last octet of BIT STRING.
+ */
+ if(type_variant == ASN_OSUBV_BIT) {
+ uint8_t b = st->bits_unused & 0x07;
+ if(b && st->size) fix_last_byte = 1;
+ ASN__CALLBACK(&b, 1);
+ }
+
+ /* 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);
+ }
+
+ ASN__ENCODED_OK(er);
+cb_failed:
+ ASN__ENCODE_FAILED;
+}
Code Review / sim / e2-interface.git / blobdiff