| /*- |
| * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved. |
| * Redistribution and modifications are permitted subject to BSD license. |
| */ |
| #include <constr_SET.h> |
| #include <assert.h> /* for assert() */ |
| |
| #ifndef WIN32 |
| #include <netinet/in.h> /* for ntohl() */ |
| #else |
| #include <winsock2.h> /* for ntohl() */ |
| #endif |
| |
| /* |
| * 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. |
| */ |
| #define ADVANCE(num_bytes) do { \ |
| size_t num = num_bytes; \ |
| ptr = ((char *)ptr) + num; \ |
| size -= num; \ |
| if(ctx->left >= 0) \ |
| ctx->left -= num; \ |
| consumed_myself += num; \ |
| } while(0) |
| |
| /* |
| * Switch to the next phase of parsing. |
| */ |
| #define NEXT_PHASE(ctx) do { \ |
| ctx->phase++; \ |
| ctx->step = 0; \ |
| } while(0) |
| |
| /* |
| * Return a standardized complex structure. |
| */ |
| #define RETURN(_code) do { \ |
| rval.code = _code; \ |
| rval.consumed = consumed_myself;\ |
| return rval; \ |
| } while(0) |
| |
| /* |
| * Tags are canonically sorted in the tag2element map. |
| */ |
| static int |
| _t2e_cmp(const void *ap, const void *bp) { |
| const asn1_TYPE_tag2member_t *a = (const asn1_TYPE_tag2member_t *)ap; |
| const asn1_TYPE_tag2member_t *b = (const asn1_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) |
| 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 SET type. |
| */ |
| ber_dec_rval_t |
| SET_decode_ber(asn1_TYPE_descriptor_t *td, |
| void **struct_ptr, void *ptr, size_t size, int tag_mode) { |
| /* |
| * Bring closer parts of structure description. |
| */ |
| asn1_SET_specifics_t *specs = (asn1_SET_specifics_t *)td->specifics; |
| asn1_TYPE_member_t *elements = td->elements; |
| |
| /* |
| * Parts of the structure being constructed. |
| */ |
| void *st = *struct_ptr; /* Target structure. */ |
| ber_dec_ctx_t *ctx; /* Decoder context */ |
| |
| ber_tlv_tag_t tlv_tag; /* T from TLV */ |
| //ber_tlv_len_t tlv_len; /* L from TLV */ |
| ber_dec_rval_t rval; /* Return code from subparsers */ |
| |
| ssize_t consumed_myself = 0; /* Consumed bytes from ptr */ |
| int edx; /* SET element's index */ |
| |
| ASN_DEBUG("Decoding %s as SET", 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 = (ber_dec_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(td, ctx, ptr, size, |
| tag_mode, &ctx->left, 0); |
| if(rval.code != RC_OK) { |
| ASN_DEBUG("%s tagging check failed: %d", |
| td->name, rval.code); |
| consumed_myself += rval.consumed; |
| RETURN(rval.code); |
| } |
| |
| if(ctx->left >= 0) |
| ctx->left += rval.consumed; /* ?Substracted below! */ |
| ADVANCE(rval.consumed); |
| |
| NEXT_PHASE(ctx); |
| |
| ASN_DEBUG("Structure advertised %ld bytes, " |
| "buffer contains %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 = (2 * <member_number> + <microphase>). |
| * Note, however, that the elements in BER may arrive out of |
| * order, yet DER mandates that they shall arive in the |
| * canonical order of their tags. So, there is a room |
| * for optimization. |
| */ |
| for(edx = (ctx->step >> 1); edx < td->elements_count; |
| ctx->step = (ctx->step & ~1) + 2, |
| edx = (ctx->step >> 1)) { |
| void *memb_ptr; /* Pointer to the member */ |
| void **memb_ptr2; /* Pointer to that pointer */ |
| ssize_t tag_len; /* Length of TLV's T */ |
| |
| if(ctx->step & 1) |
| goto microphase2; |
| |
| /* |
| * MICROPHASE 1: Synchronize decoding. |
| */ |
| |
| if(ctx->left == 0) |
| /* |
| * No more things to decode. |
| * Exit out of here and check whether all mandatory |
| * elements have been received (in the next phase). |
| */ |
| break; |
| |
| /* |
| * Fetch the T from TLV. |
| */ |
| tag_len = ber_fetch_tag(ptr, LEFT, &tlv_tag); |
| switch(tag_len) { |
| case 0: if(!SIZE_VIOLATION) RETURN(RC_WMORE); |
| /* Fall through */ |
| case -1: RETURN(RC_FAIL); |
| } |
| |
| if(ctx->left < 0 && ((uint8_t *)ptr)[0] == 0) { |
| if(LEFT < 2) { |
| if(SIZE_VIOLATION) |
| RETURN(RC_FAIL); |
| else |
| RETURN(RC_WMORE); |
| } else if(((uint8_t *)ptr)[1] == 0) { |
| /* |
| * Found the terminator of the |
| * indefinite length structure. |
| * Invoke the generic finalization function. |
| */ |
| goto phase3; |
| } |
| } |
| |
| if(BER_TAGS_EQUAL(tlv_tag, elements[edx].tag)) { |
| /* |
| * The elements seem to go in order. |
| * This is not particularly strange, |
| * but is not strongly anticipated either. |
| */ |
| } else { |
| asn1_TYPE_tag2member_t *t2m; |
| asn1_TYPE_tag2member_t key; |
| |
| key.el_tag = tlv_tag; |
| (void *)t2m = bsearch(&key, |
| specs->tag2el, specs->tag2el_count, |
| sizeof(specs->tag2el[0]), _t2e_cmp); |
| if(t2m) { |
| /* |
| * Found the element corresponding to the tag. |
| */ |
| edx = t2m->el_no; |
| ctx->step = 2 * edx; |
| } else if(specs->extensible == 0) { |
| ASN_DEBUG("Unexpected tag %s " |
| "in non-extensible SET %s", |
| ber_tlv_tag_string(tlv_tag), td->name); |
| RETURN(RC_FAIL); |
| } else { |
| /* Skip this tag */ |
| ssize_t skip; |
| |
| ASN_DEBUG("Skipping unknown tag %s", |
| ber_tlv_tag_string(tlv_tag)); |
| |
| skip = ber_skip_length( |
| BER_TLV_CONSTRUCTED(ptr), |
| (char *)ptr + tag_len, LEFT - tag_len); |
| |
| 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: |
| |
| /* |
| * Check for duplications: must not overwrite |
| * already decoded elements. |
| */ |
| if(ASN_SET_ISPRESENT2((char *)st + specs->pres_offset, edx)) { |
| ASN_DEBUG("SET %s: Duplicate element %s (%d)", |
| td->name, elements[edx].name, edx); |
| RETURN(RC_FAIL); |
| } |
| |
| /* |
| * 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].optional) { |
| /* Optional member, hereby, a simple pointer */ |
| 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 |
| */ |
| rval = elements[edx].type->ber_decoder( |
| elements[edx].type, |
| memb_ptr2, ptr, LEFT, |
| elements[edx].tag_mode); |
| switch(rval.code) { |
| case RC_OK: |
| ASN_SET_MKPRESENT((char *)st + specs->pres_offset, edx); |
| break; |
| case RC_WMORE: /* More data expected */ |
| if(!SIZE_VIOLATION) { |
| ADVANCE(rval.consumed); |
| RETURN(RC_WMORE); |
| } |
| /* Fail 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: |
| case 4: /* Only 00 is expected */ |
| ASN_DEBUG("SET %s Leftover: %ld, size = %ld", |
| td->name, (long)ctx->left, (long)size); |
| |
| /* |
| * Skip everything until the end of the SET. |
| */ |
| 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 |
| && ((uint8_t *)ptr)[0] == 0) { |
| if(LEFT < 2) { |
| if(SIZE_VIOLATION) |
| RETURN(RC_FAIL); |
| else |
| RETURN(RC_WMORE); |
| } else if(((uint8_t *)ptr)[1] == 0) { |
| /* |
| * Correctly finished with <0><0>. |
| */ |
| ADVANCE(2); |
| ctx->left++; |
| ctx->phase = 4; |
| continue; |
| } |
| } |
| |
| if(specs->extensible == 0 || ctx->phase == 4) { |
| ASN_DEBUG("Unexpected continuation " |
| "of a non-extensible type %s", |
| td->name); |
| RETURN(RC_FAIL); |
| } |
| |
| ll = ber_skip_length( |
| BER_TLV_CONSTRUCTED(ptr), |
| (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); |
| } |
| |
| ctx->phase = 5; |
| case 5: |
| /* |
| * Check that all mandatory elements are present. |
| */ |
| for(edx = 0; edx < td->elements_count; |
| edx += (8 * sizeof(specs->_mandatory_elements[0]))) { |
| unsigned int midx, pres, must; |
| |
| midx = edx/(8 * sizeof(specs->_mandatory_elements[0])); |
| pres = ((unsigned int *)((char *)st+specs->pres_offset))[midx]; |
| must = ntohl(specs->_mandatory_elements[midx]); |
| |
| if((pres & must) == must) { |
| /* |
| * Yes, everything seems to be in place. |
| */ |
| } else { |
| ASN_DEBUG("One or more mandatory elements " |
| "of a SET %s %d (%08x.%08x)=%08x " |
| "are not present", |
| td->name, |
| midx, |
| pres, |
| must, |
| (~(pres & must) & must) |
| ); |
| RETURN(RC_FAIL); |
| } |
| } |
| |
| NEXT_PHASE(ctx); |
| } |
| |
| RETURN(RC_OK); |
| } |
| |
| /* |
| * The DER encoder of the SET type. |
| */ |
| der_enc_rval_t |
| SET_encode_der(asn1_TYPE_descriptor_t *td, |
| void *ptr, int tag_mode, ber_tlv_tag_t tag, |
| asn_app_consume_bytes_f *cb, void *app_key) { |
| asn1_SET_specifics_t *specs = (asn1_SET_specifics_t *)td->specifics; |
| size_t computed_size = 0; |
| der_enc_rval_t my_erval; |
| int t2m_build_own = (specs->tag2el_count != td->elements_count); |
| asn1_TYPE_tag2member_t *t2m; |
| int t2m_count; |
| ssize_t ret; |
| int edx; |
| |
| /* |
| * Use existing, or build our own tags map. |
| */ |
| if(t2m_build_own) { |
| (void *)t2m = alloca(td->elements_count * sizeof(t2m[0])); |
| if(!t2m) { /* There are such platforms */ |
| my_erval.encoded = -1; |
| my_erval.failed_type = td; |
| my_erval.structure_ptr = ptr; |
| return my_erval; |
| } |
| t2m_count = 0; |
| } else { |
| /* |
| * There is no untagged CHOICE in this SET. |
| * Employ existing table. |
| */ |
| t2m = specs->tag2el; |
| t2m_count = specs->tag2el_count; |
| } |
| |
| /* |
| * Gather the length of the underlying members sequence. |
| */ |
| for(edx = 0; edx < td->elements_count; edx++) { |
| asn1_TYPE_member_t *elm = &td->elements[edx]; |
| der_enc_rval_t erval; |
| void *memb_ptr; |
| |
| /* |
| * Compute the length of the encoding of this member. |
| */ |
| if(elm->optional) { |
| memb_ptr = *(void **)((char *)ptr + elm->memb_offset); |
| if(!memb_ptr) { |
| if(t2m_build_own) { |
| t2m[t2m_count].el_no = edx; |
| t2m[t2m_count].el_tag = 0; |
| t2m_count++; |
| } |
| 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; |
| |
| /* |
| * Remember the outmost tag of this member. |
| */ |
| if(t2m_build_own) { |
| t2m[t2m_count].el_no = edx; |
| t2m[t2m_count].el_tag = asn1_TYPE_outmost_tag( |
| elm->type, memb_ptr, elm->tag_mode, elm->tag); |
| t2m_count++; |
| } else { |
| /* |
| * No dynamic sorting is necessary. |
| */ |
| } |
| } |
| |
| /* |
| * Finalize order of the components. |
| */ |
| assert(t2m_count == td->elements_count); |
| if(t2m_build_own) { |
| /* |
| * Sort the underlying members according to their |
| * canonical tags order. DER encoding mandates it. |
| */ |
| qsort(t2m, t2m_count, sizeof(specs->tag2el[0]), _t2e_cmp); |
| } else { |
| /* |
| * Tags are already sorted by the compiler. |
| */ |
| } |
| |
| /* |
| * Encode the TLV for the sequence itself. |
| */ |
| ret = der_write_tags(td, computed_size, tag_mode, tag, cb, app_key); |
| if(ret == -1) { |
| my_erval.encoded = -1; |
| my_erval.failed_type = td; |
| my_erval.structure_ptr = ptr; |
| return my_erval; |
| } |
| my_erval.encoded = computed_size + ret; |
| |
| if(!cb) return my_erval; |
| |
| /* |
| * Encode all members. |
| */ |
| for(edx = 0; edx < td->elements_count; edx++) { |
| asn1_TYPE_member_t *elm; |
| der_enc_rval_t erval; |
| void *memb_ptr; |
| |
| /* Encode according to the tag order */ |
| elm = &td->elements[t2m[edx].el_no]; |
| |
| if(elm->optional) { |
| 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, |
| cb, app_key); |
| if(erval.encoded == -1) |
| return erval; |
| computed_size -= erval.encoded; |
| } |
| |
| if(computed_size != 0) { |
| /* |
| * Encoded size is not equal to the computed size. |
| */ |
| my_erval.encoded = -1; |
| my_erval.failed_type = td; |
| my_erval.structure_ptr = ptr; |
| } |
| |
| return my_erval; |
| } |
| |
| int |
| SET_print(asn1_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); |
| |
| /* Dump preamble */ |
| if(cb(td->name, strlen(td->name), app_key) |
| || cb(" ::= {\n", 7, app_key)) |
| return -1; |
| |
| for(edx = 0; edx < td->elements_count; edx++) { |
| asn1_TYPE_member_t *elm = &td->elements[edx]; |
| const void *memb_ptr; |
| |
| if(elm->optional) { |
| 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 */ |
| for(ret = 0; ret < ilevel; ret++) cb(" ", 1, app_key); |
| |
| /* Print the member's name and stuff */ |
| if(cb(elm->name, strlen(elm->name), app_key) |
| || cb(": ", 2, app_key)) |
| return -1; |
| |
| /* Print the member itself */ |
| ret = elm->type->print_struct(elm->type, memb_ptr, ilevel + 4, |
| cb, app_key); |
| if(ret) return ret; |
| |
| ret = cb("\n", 1, app_key); |
| if(ret) return ret; |
| } |
| |
| /* Indentation */ |
| for(ret = 0; ret < ilevel - 4; ret++) cb(" ", 1, app_key); |
| |
| return cb("}", 1, app_key); |
| } |
| |
| void |
| SET_free(asn1_TYPE_descriptor_t *td, void *ptr, int contents_only) { |
| int edx; |
| |
| if(!td || !ptr) |
| return; |
| |
| ASN_DEBUG("Freeing %s as SET", td->name); |
| |
| for(edx = 0; edx < td->elements_count; edx++) { |
| asn1_TYPE_member_t *elm = &td->elements[edx]; |
| void *memb_ptr; |
| if(elm->optional) { |
| memb_ptr = *(void **)((char *)ptr + elm->memb_offset); |
| if(memb_ptr) |
| elm->type->free_struct(elm->type, memb_ptr, 0); |
| } else { |
| memb_ptr = (void *)((char *)ptr + elm->memb_offset); |
| elm->type->free_struct(elm->type, memb_ptr, 1); |
| } |
| } |
| |
| if(!contents_only) { |
| FREEMEM(ptr); |
| } |
| } |
| |
| int |
| SET_constraint(asn1_TYPE_descriptor_t *td, const void *sptr, |
| asn_app_consume_bytes_f *app_errlog, void *app_key) { |
| asn1_SET_specifics_t *specs = (asn1_SET_specifics_t *)td->specifics; |
| 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++) { |
| asn1_TYPE_member_t *elm = &td->elements[edx]; |
| const void *memb_ptr; |
| |
| if(elm->optional) { |
| memb_ptr = *(const void * const *)((const char *)sptr + elm->memb_offset); |
| if(!memb_ptr) { |
| if(ASN_SET_ISPRESENT2( |
| &(specs->_mandatory_elements), edx)) { |
| _ASN_ERRLOG(app_errlog, app_key, |
| "%s: mandatory element " |
| "%s absent (%s:%d)", |
| td->name, elm->name, |
| __FILE__, __LINE__); |
| return -1; |
| } |
| 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; |
| } |