/* $OpenBSD: tasn_dec.c,v 1.85 2023/04/28 17:59:53 job Exp $ */ /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL * project 2000. */ /* ==================================================================== * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. All advertising materials mentioning features or use of this * software must display the following acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" * * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to * endorse or promote products derived from this software without * prior written permission. For written permission, please contact * licensing@OpenSSL.org. * * 5. Products derived from this software may not be called "OpenSSL" * nor may "OpenSSL" appear in their names without prior written * permission of the OpenSSL Project. * * 6. Redistributions of any form whatsoever must retain the following * acknowledgment: * "This product includes software developed by the OpenSSL Project * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" * * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * ==================================================================== * * This product includes cryptographic software written by Eric Young * (eay@cryptsoft.com). This product includes software written by Tim * Hudson (tjh@cryptsoft.com). * */ #include #include #include #include #include #include #include #include #include "asn1_local.h" #include "bytestring.h" /* * Constructed types with a recursive definition (such as can be found in PKCS7) * could eventually exceed the stack given malicious input with excessive * recursion. Therefore we limit the stack depth. */ #define ASN1_MAX_CONSTRUCTED_NEST 30 #ifndef ASN1_MAX_STRING_NEST /* * This determines how many levels of recursion are permitted in ASN.1 string * types. If it is not limited stack overflows can occur. If set to zero no * recursion is allowed at all. */ #define ASN1_MAX_STRING_NEST 5 #endif static int asn1_template_d2i(ASN1_VALUE **pval, CBS *cbs, const ASN1_TEMPLATE *at, int optional, int depth); static int asn1_check_eoc(CBS *cbs) { uint16_t eoc; if (!CBS_peek_u16(cbs, &eoc)) return 0; if (eoc != 0) return 0; return CBS_skip(cbs, 2); } static int asn1_check_tag(CBS *cbs, size_t *out_len, int *out_tag, uint8_t *out_class, int *out_indefinite, int *out_constructed, int expected_tag, int expected_class, int optional) { int constructed, indefinite; uint32_t tag_number; uint8_t tag_class; size_t length; if (out_len != NULL) *out_len = 0; if (out_tag != NULL) *out_tag = 0; if (out_class != NULL) *out_class = 0; if (out_indefinite != NULL) *out_indefinite = 0; if (out_constructed != NULL) *out_constructed = 0; if (!asn1_get_identifier_cbs(cbs, 0, &tag_class, &constructed, &tag_number)) { ASN1error(ASN1_R_BAD_OBJECT_HEADER); return 0; } if (expected_tag >= 0) { if (expected_tag != tag_number || expected_class != tag_class << 6) { /* Indicate missing type if this is OPTIONAL. */ if (optional) return -1; ASN1error(ASN1_R_WRONG_TAG); return 0; } } if (!asn1_get_length_cbs(cbs, 0, &indefinite, &length)) { ASN1error(ASN1_R_BAD_OBJECT_HEADER); return 0; } /* Indefinite length can only be used with constructed encoding. */ if (indefinite && !constructed) { ASN1error(ASN1_R_BAD_OBJECT_HEADER); return 0; } if (!indefinite && CBS_len(cbs) < length) { ASN1error(ASN1_R_TOO_LONG); return 0; } if (tag_number > INT_MAX) { ASN1error(ASN1_R_TOO_LONG); return 0; } if (indefinite) length = CBS_len(cbs); if (out_len != NULL) *out_len = length; if (out_tag != NULL) *out_tag = tag_number; if (out_class != NULL) *out_class = tag_class << 6; if (out_indefinite != NULL) *out_indefinite = indefinite; if (out_constructed != NULL) *out_constructed = constructed; return 1; } /* Collect the contents from a constructed ASN.1 object. */ static int asn1_collect(CBB *cbb, CBS *cbs, int indefinite, int expected_tag, int expected_class, int depth) { int constructed; size_t length; CBS content; int need_eoc; if (depth > ASN1_MAX_STRING_NEST) { ASN1error(ASN1_R_NESTED_ASN1_STRING); return 0; } need_eoc = indefinite; while (CBS_len(cbs) > 0) { if (asn1_check_eoc(cbs)) { if (!need_eoc) { ASN1error(ASN1_R_UNEXPECTED_EOC); return 0; } return 1; } if (!asn1_check_tag(cbs, &length, NULL, NULL, &indefinite, &constructed, expected_tag, expected_class, 0)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (constructed) { if (!asn1_collect(cbb, cbs, indefinite, expected_tag, expected_class, depth + 1)) return 0; continue; } if (!CBS_get_bytes(cbs, &content, length)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (!CBB_add_bytes(cbb, CBS_data(&content), CBS_len(&content))) return 0; } if (need_eoc) { ASN1error(ASN1_R_MISSING_EOC); return 0; } return 1; } /* Find the end of an ASN.1 object. */ static int asn1_find_end(CBS *cbs, size_t length, int indefinite) { size_t eoc_count; if (!indefinite) { if (!CBS_skip(cbs, length)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } return 1; } eoc_count = 1; while (CBS_len(cbs) > 0) { if (asn1_check_eoc(cbs)) { if (--eoc_count == 0) break; continue; } if (!asn1_check_tag(cbs, &length, NULL, NULL, &indefinite, NULL, -1, 0, 0)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (indefinite) { eoc_count++; continue; } if (!CBS_skip(cbs, length)) return 0; } if (eoc_count > 0) { ASN1error(ASN1_R_MISSING_EOC); return 0; } return 1; } static int asn1_c2i_primitive(ASN1_VALUE **pval, CBS *content, int utype, const ASN1_ITEM *it) { ASN1_BOOLEAN *abool; ASN1_STRING *astr; uint8_t val; int ret = 0; if (it->funcs != NULL) goto err; if (CBS_len(content) > INT_MAX) goto err; switch (utype) { case V_ASN1_OBJECT: if (!c2i_ASN1_OBJECT_cbs((ASN1_OBJECT **)pval, content)) goto err; break; case V_ASN1_NULL: if (CBS_len(content) != 0) { ASN1error(ASN1_R_NULL_IS_WRONG_LENGTH); goto err; } *pval = (ASN1_VALUE *)1; break; case V_ASN1_BOOLEAN: abool = (ASN1_BOOLEAN *)pval; if (CBS_len(content) != 1) { ASN1error(ASN1_R_BOOLEAN_IS_WRONG_LENGTH); goto err; } if (!CBS_get_u8(content, &val)) goto err; *abool = val; break; case V_ASN1_BIT_STRING: if (!c2i_ASN1_BIT_STRING_cbs((ASN1_BIT_STRING **)pval, content)) goto err; break; case V_ASN1_ENUMERATED: if (!c2i_ASN1_ENUMERATED_cbs((ASN1_ENUMERATED **)pval, content)) goto err; break; case V_ASN1_INTEGER: if (!c2i_ASN1_INTEGER_cbs((ASN1_INTEGER **)pval, content)) goto err; break; case V_ASN1_OCTET_STRING: case V_ASN1_NUMERICSTRING: case V_ASN1_PRINTABLESTRING: case V_ASN1_T61STRING: case V_ASN1_VIDEOTEXSTRING: case V_ASN1_IA5STRING: case V_ASN1_UTCTIME: case V_ASN1_GENERALIZEDTIME: case V_ASN1_GRAPHICSTRING: case V_ASN1_VISIBLESTRING: case V_ASN1_GENERALSTRING: case V_ASN1_UNIVERSALSTRING: case V_ASN1_BMPSTRING: case V_ASN1_UTF8STRING: case V_ASN1_OTHER: case V_ASN1_SET: case V_ASN1_SEQUENCE: default: if (utype == V_ASN1_BMPSTRING && (CBS_len(content) & 1)) { ASN1error(ASN1_R_BMPSTRING_IS_WRONG_LENGTH); goto err; } if (utype == V_ASN1_UNIVERSALSTRING && (CBS_len(content) & 3)) { ASN1error(ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH); goto err; } if (utype == V_ASN1_UTCTIME || utype == V_ASN1_GENERALIZEDTIME) { if (!asn1_time_parse_cbs(content, utype == V_ASN1_GENERALIZEDTIME, NULL)) { ASN1error(ASN1_R_INVALID_TIME_FORMAT); goto err; } } /* All based on ASN1_STRING and handled the same way. */ if (*pval != NULL) { ASN1_STRING_free((ASN1_STRING *)*pval); *pval = NULL; } if ((astr = ASN1_STRING_type_new(utype)) == NULL) { ASN1error(ERR_R_MALLOC_FAILURE); goto err; } if (!ASN1_STRING_set(astr, CBS_data(content), CBS_len(content))) { ASN1_STRING_free(astr); goto err; } *pval = (ASN1_VALUE *)astr; break; } ret = 1; err: return ret; } static int asn1_c2i_any(ASN1_VALUE **pval, CBS *content, int utype, const ASN1_ITEM *it) { ASN1_TYPE *atype; if (it->utype != V_ASN1_ANY || it->funcs != NULL) return 0; if (*pval != NULL) { ASN1_TYPE_free((ASN1_TYPE *)*pval); *pval = NULL; } if ((atype = ASN1_TYPE_new()) == NULL) return 0; if (!asn1_c2i_primitive(&atype->value.asn1_value, content, utype, it)) { ASN1_TYPE_free(atype); return 0; } atype->type = utype; /* Fix up value for ASN.1 NULL. */ if (atype->type == V_ASN1_NULL) atype->value.ptr = NULL; *pval = (ASN1_VALUE *)atype; return 1; } static int asn1_c2i(ASN1_VALUE **pval, CBS *content, int utype, const ASN1_ITEM *it) { if (CBS_len(content) > INT_MAX) return 0; if (it->funcs != NULL) { const ASN1_PRIMITIVE_FUNCS *pf = it->funcs; char free_content = 0; if (pf->prim_c2i == NULL) return 0; return pf->prim_c2i(pval, CBS_data(content), CBS_len(content), utype, &free_content, it); } if (it->utype == V_ASN1_ANY) return asn1_c2i_any(pval, content, utype, it); return asn1_c2i_primitive(pval, content, utype, it); } /* * Decode ASN.1 content into a primitive type. There are three possible forms - * a SEQUENCE/SET/OTHER that is stored verbatim (including the ASN.1 tag and * length octets), constructed objects and non-constructed objects. In the * first two cases indefinite length is permitted, which we may need to handle. * When this function is called the *cbs should reference the start of the * ASN.1 object (i.e. the tag/length header), while *cbs_object should * reference the start of the object contents (i.e. after the tag/length * header. Additionally, the *cbs_object offset should be relative to the * ASN.1 object being parsed. On success the *cbs will point at the octet * after the object. */ static int asn1_d2i_primitive_content(ASN1_VALUE **pval, CBS *cbs, CBS *cbs_object, int utype, int constructed, int indefinite, size_t length, const ASN1_ITEM *it) { CBS cbs_content, cbs_initial; uint8_t *data = NULL; size_t data_len = 0; CBB cbb; int ret = 0; memset(&cbb, 0, sizeof(cbb)); CBS_dup(cbs, &cbs_initial); CBS_init(&cbs_content, NULL, 0); if (asn1_must_be_constructed(utype) && !constructed) { ASN1error(ASN1_R_TYPE_NOT_CONSTRUCTED); goto err; } if (asn1_must_be_primitive(utype) && constructed) { ASN1error(ASN1_R_TYPE_NOT_PRIMITIVE); goto err; } /* SEQUENCE, SET and "OTHER" are left in encoded form. */ if (utype == V_ASN1_SEQUENCE || utype == V_ASN1_SET || utype == V_ASN1_OTHER) { if (!asn1_find_end(cbs_object, length, indefinite)) goto err; if (!CBS_get_bytes(&cbs_initial, &cbs_content, CBS_offset(cbs_object))) goto err; } else if (constructed) { /* * Should really check the internal tags are correct but * some things may get this wrong. The relevant specs * say that constructed string types should be OCTET STRINGs * internally irrespective of the type. So instead just check * for UNIVERSAL class and ignore the tag. */ if (!CBB_init(&cbb, 0)) goto err; if (!asn1_collect(&cbb, cbs_object, indefinite, -1, V_ASN1_UNIVERSAL, 0)) goto err; if (!CBB_finish(&cbb, &data, &data_len)) goto err; CBS_init(&cbs_content, data, data_len); } else { if (!CBS_get_bytes(cbs_object, &cbs_content, length)) goto err; } if (!asn1_c2i(pval, &cbs_content, utype, it)) goto err; if (!CBS_skip(cbs, CBS_offset(cbs_object))) goto err; ret = 1; err: CBB_cleanup(&cbb); freezero(data, data_len); return ret; } static int asn1_d2i_any(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional) { int constructed, indefinite; uint8_t object_class; int object_type; CBS cbs_object; size_t length; CBS_init(&cbs_object, CBS_data(cbs), CBS_len(cbs)); if (it->utype != V_ASN1_ANY) return 0; if (tag_number >= 0) { ASN1error(ASN1_R_ILLEGAL_TAGGED_ANY); return 0; } if (optional) { ASN1error(ASN1_R_ILLEGAL_OPTIONAL_ANY); return 0; } /* Determine type from ASN.1 tag. */ if (asn1_check_tag(&cbs_object, &length, &object_type, &object_class, &indefinite, &constructed, -1, 0, 0) != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (object_class != V_ASN1_UNIVERSAL) object_type = V_ASN1_OTHER; return asn1_d2i_primitive_content(pval, cbs, &cbs_object, object_type, constructed, indefinite, length, it); } static int asn1_d2i_mstring(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional) { int constructed, indefinite; uint8_t object_class; int object_tag; CBS cbs_object; size_t length; CBS_init(&cbs_object, CBS_data(cbs), CBS_len(cbs)); /* * It never makes sense for multi-strings to have implicit tagging, so * if tag_number != -1, then this looks like an error in the template. */ if (tag_number != -1) { ASN1error(ASN1_R_BAD_TEMPLATE); return 0; } if (asn1_check_tag(&cbs_object, &length, &object_tag, &object_class, &indefinite, &constructed, -1, 0, 1) != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } /* Class must be UNIVERSAL. */ if (object_class != V_ASN1_UNIVERSAL) { if (optional) return -1; ASN1error(ASN1_R_MSTRING_NOT_UNIVERSAL); return 0; } /* Check tag matches bit map. */ if ((ASN1_tag2bit(object_tag) & it->utype) == 0) { if (optional) return -1; ASN1error(ASN1_R_MSTRING_WRONG_TAG); return 0; } return asn1_d2i_primitive_content(pval, cbs, &cbs_object, object_tag, constructed, indefinite, length, it); } static int asn1_d2i_primitive(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional) { CBS cbs_object; int constructed, indefinite; int utype = it->utype; size_t length; int ret; CBS_init(&cbs_object, CBS_data(cbs), CBS_len(cbs)); if (it->itype == ASN1_ITYPE_MSTRING) return 0; if (it->utype == V_ASN1_ANY) return asn1_d2i_any(pval, cbs, it, tag_number, tag_class, optional); if (tag_number == -1) { tag_number = it->utype; tag_class = V_ASN1_UNIVERSAL; } ret = asn1_check_tag(&cbs_object, &length, NULL, NULL, &indefinite, &constructed, tag_number, tag_class, optional); if (ret == -1) return -1; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } return asn1_d2i_primitive_content(pval, cbs, &cbs_object, utype, constructed, indefinite, length, it); } static int asn1_item_d2i_choice(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional, int depth) { const ASN1_TEMPLATE *at, *errat = NULL; const ASN1_AUX *aux; ASN1_aux_cb *asn1_cb = NULL; ASN1_VALUE *achoice = NULL; ASN1_VALUE **pchptr; int i, ret; if ((aux = it->funcs) != NULL) asn1_cb = aux->asn1_cb; if (it->itype != ASN1_ITYPE_CHOICE) goto err; /* * It never makes sense for CHOICE types to have implicit tagging, so * if tag_number != -1, then this looks like an error in the template. */ if (tag_number != -1) { ASN1error(ASN1_R_BAD_TEMPLATE); goto err; } if (*pval != NULL) { ASN1_item_ex_free(pval, it); *pval = NULL; } if (!ASN1_item_ex_new(&achoice, it)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); goto err; } if (asn1_cb != NULL && !asn1_cb(ASN1_OP_D2I_PRE, &achoice, it, NULL)) { ASN1error(ASN1_R_AUX_ERROR); goto err; } /* Try each possible CHOICE in turn. */ for (i = 0; i < it->tcount; i++) { at = &it->templates[i]; pchptr = asn1_get_field_ptr(&achoice, at); /* Mark field as OPTIONAL so its absence can be identified. */ ret = asn1_template_d2i(pchptr, cbs, at, 1, depth); if (ret == -1) continue; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); errat = at; goto err; } /* We've successfully decoded an ASN.1 object. */ asn1_set_choice_selector(&achoice, i, it); break; } /* Did we fall off the end without reading anything? */ if (i == it->tcount) { if (optional) { ASN1_item_ex_free(&achoice, it); return -1; } ASN1error(ASN1_R_NO_MATCHING_CHOICE_TYPE); goto err; } if (asn1_cb != NULL && !asn1_cb(ASN1_OP_D2I_POST, &achoice, it, NULL)) { ASN1error(ASN1_R_AUX_ERROR); goto err; } *pval = achoice; achoice = NULL; return 1; err: ASN1_item_ex_free(&achoice, it); if (errat != NULL) ERR_asprintf_error_data("Field=%s, Type=%s", errat->field_name, it->sname); else ERR_asprintf_error_data("Type=%s", it->sname); return 0; } static int asn1_item_d2i_sequence(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional, int depth) { CBS cbs_seq, cbs_seq_content; int constructed, indefinite, optional_field; const ASN1_TEMPLATE *errat = NULL; const ASN1_TEMPLATE *seqat, *at; ASN1_aux_cb *asn1_cb = NULL; const ASN1_AUX *aux; ASN1_VALUE *aseq = NULL; ASN1_VALUE **pseqval; int eoc_needed, i; size_t length; int ret = 0; CBS_init(&cbs_seq, CBS_data(cbs), CBS_len(cbs)); if ((aux = it->funcs) != NULL) asn1_cb = aux->asn1_cb; if (it->itype != ASN1_ITYPE_NDEF_SEQUENCE && it->itype != ASN1_ITYPE_SEQUENCE) goto err; if (*pval != NULL) { ASN1_item_ex_free(pval, it); *pval = NULL; } /* If no IMPLICIT tagging use UNIVERSAL/SEQUENCE. */ if (tag_number == -1) { tag_class = V_ASN1_UNIVERSAL; tag_number = V_ASN1_SEQUENCE; } /* Read ASN.1 SEQUENCE header. */ ret = asn1_check_tag(&cbs_seq, &length, NULL, NULL, &indefinite, &constructed, tag_number, tag_class, optional); if (ret == -1) return -1; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); goto err; } if (!constructed) { ASN1error(ASN1_R_SEQUENCE_NOT_CONSTRUCTED); goto err; } if (indefinite) { eoc_needed = 1; CBS_init(&cbs_seq_content, CBS_data(&cbs_seq), CBS_len(&cbs_seq)); } else { eoc_needed = 0; if (!CBS_get_bytes(&cbs_seq, &cbs_seq_content, length)) goto err; } if (!ASN1_item_ex_new(&aseq, it)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); goto err; } if (asn1_cb != NULL && !asn1_cb(ASN1_OP_D2I_PRE, &aseq, it, NULL)) { ASN1error(ASN1_R_AUX_ERROR); goto err; } for (i = 0; i < it->tcount; i++) { at = &it->templates[i]; if (asn1_check_eoc(&cbs_seq_content)) { if (!indefinite) { ASN1error(ASN1_R_UNEXPECTED_EOC); goto err; } eoc_needed = 0; break; } if (CBS_len(&cbs_seq_content) == 0) break; if ((seqat = asn1_do_adb(&aseq, at, 1)) == NULL) goto err; pseqval = asn1_get_field_ptr(&aseq, seqat); /* * This was originally implemented to "increase efficiency", * however it currently needs to remain since it papers over * the use of ASN.1 ANY with OPTIONAL in SEQUENCEs (which * asn1_d2i_primitive() currently rejects). */ optional_field = (seqat->flags & ASN1_TFLG_OPTIONAL) != 0; if (i == it->tcount - 1) optional_field = 0; ret = asn1_template_d2i(pseqval, &cbs_seq_content, seqat, optional_field, depth); if (ret == -1) { /* Absent OPTIONAL component. */ ASN1_template_free(pseqval, seqat); continue; } if (ret != 1) { errat = seqat; goto err; } } if (eoc_needed && !asn1_check_eoc(&cbs_seq_content)) { ASN1error(ASN1_R_MISSING_EOC); goto err; } if (indefinite) { if (!CBS_skip(&cbs_seq, CBS_offset(&cbs_seq_content))) goto err; } else if (CBS_len(&cbs_seq_content) != 0) { ASN1error(ASN1_R_SEQUENCE_LENGTH_MISMATCH); goto err; } /* * There is no more data in the ASN.1 SEQUENCE, however we may not have * populated all fields - check that any remaining are OPTIONAL. */ for (; i < it->tcount; i++) { at = &it->templates[i]; if ((seqat = asn1_do_adb(&aseq, at, 1)) == NULL) goto err; if ((seqat->flags & ASN1_TFLG_OPTIONAL) == 0) { ASN1error(ASN1_R_FIELD_MISSING); errat = seqat; goto err; } /* XXX - this is probably unnecessary with earlier free. */ pseqval = asn1_get_field_ptr(&aseq, seqat); ASN1_template_free(pseqval, seqat); } if (!CBS_skip(cbs, CBS_offset(&cbs_seq))) goto err; if (asn1_cb != NULL && !asn1_cb(ASN1_OP_D2I_POST, &aseq, it, NULL)) { ASN1error(ASN1_R_AUX_ERROR); goto err; } *pval = aseq; aseq = NULL; return 1; err: ASN1_item_ex_free(&aseq, it); if (errat != NULL) ERR_asprintf_error_data("Field=%s, Type=%s", errat->field_name, it->sname); else ERR_asprintf_error_data("Type=%s", it->sname); return 0; } static int asn1_item_d2i_extern(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional) { const ASN1_EXTERN_FUNCS *ef = it->funcs; const unsigned char *p = NULL; ASN1_TLC ctx = { 0 }; int ret = 0; if (CBS_len(cbs) > LONG_MAX) return 0; p = CBS_data(cbs); if ((ret = ef->asn1_ex_d2i(pval, &p, (long)CBS_len(cbs), it, tag_number, tag_class, optional, &ctx)) == 1) { if (!CBS_skip(cbs, p - CBS_data(cbs))) goto err; } return ret; err: ASN1_item_ex_free(pval, it); ERR_asprintf_error_data("Type=%s", it->sname); return 0; } static int asn1_item_d2i(ASN1_VALUE **pval, CBS *cbs, const ASN1_ITEM *it, int tag_number, int tag_class, int optional, int depth) { if (pval == NULL) return 0; if (++depth > ASN1_MAX_CONSTRUCTED_NEST) { ASN1error(ASN1_R_NESTED_TOO_DEEP); goto err; } switch (it->itype) { case ASN1_ITYPE_PRIMITIVE: if (it->templates != NULL) { /* * Tagging or OPTIONAL is currently illegal on an item * template because the flags can't get passed down. * In practice this isn't a problem: we include the * relevant flags from the item template in the * template itself. */ if (tag_number != -1 || optional) { ASN1error(ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); goto err; } return asn1_template_d2i(pval, cbs, it->templates, optional, depth); } return asn1_d2i_primitive(pval, cbs, it, tag_number, tag_class, optional); case ASN1_ITYPE_MSTRING: return asn1_d2i_mstring(pval, cbs, it, tag_number, tag_class, optional); case ASN1_ITYPE_EXTERN: return asn1_item_d2i_extern(pval, cbs, it, tag_number, tag_class, optional); case ASN1_ITYPE_CHOICE: return asn1_item_d2i_choice(pval, cbs, it, tag_number, tag_class, optional, depth); case ASN1_ITYPE_NDEF_SEQUENCE: case ASN1_ITYPE_SEQUENCE: return asn1_item_d2i_sequence(pval, cbs, it, tag_number, tag_class, optional, depth); default: return 0; } err: ASN1_item_ex_free(pval, it); ERR_asprintf_error_data("Type=%s", it->sname); return 0; } static void asn1_template_stack_of_free(STACK_OF(ASN1_VALUE) *avals, const ASN1_TEMPLATE *at) { ASN1_VALUE *aval; if (avals == NULL) return; while (sk_ASN1_VALUE_num(avals) > 0) { aval = sk_ASN1_VALUE_pop(avals); ASN1_item_ex_free(&aval, at->item); } sk_ASN1_VALUE_free(avals); } static int asn1_template_stack_of_d2i(ASN1_VALUE **pval, CBS *cbs, const ASN1_TEMPLATE *at, int optional, int depth) { CBS cbs_object, cbs_object_content; STACK_OF(ASN1_VALUE) *avals = NULL; ASN1_VALUE *aval = NULL; int tag_number, tag_class; int eoc_needed; int indefinite; size_t length; int ret; CBS_init(&cbs_object, CBS_data(cbs), CBS_len(cbs)); if (pval == NULL) return 0; asn1_template_stack_of_free((STACK_OF(ASN1_VALUE) *)*pval, at); *pval = NULL; tag_number = at->tag; tag_class = at->flags & ASN1_TFLG_TAG_CLASS; /* Determine the inner tag value for SET OF or SEQUENCE OF. */ if ((at->flags & ASN1_TFLG_IMPTAG) == 0) { tag_number = V_ASN1_SEQUENCE; tag_class = V_ASN1_UNIVERSAL; if ((at->flags & ASN1_TFLG_SET_OF) != 0) tag_number = V_ASN1_SET; } ret = asn1_check_tag(&cbs_object, &length, NULL, NULL, &indefinite, NULL, tag_number, tag_class, optional); if (ret == -1) return -1; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (indefinite) { eoc_needed = 1; CBS_init(&cbs_object_content, CBS_data(&cbs_object), CBS_len(&cbs_object)); } else { eoc_needed = 0; if (!CBS_get_bytes(&cbs_object, &cbs_object_content, length)) goto err; } if ((avals = sk_ASN1_VALUE_new_null()) == NULL) { ASN1error(ERR_R_MALLOC_FAILURE); goto err; } /* Read as many items as possible. */ while (CBS_len(&cbs_object_content) > 0) { if (asn1_check_eoc(&cbs_object_content)) { if (!eoc_needed) { ASN1error(ASN1_R_UNEXPECTED_EOC); goto err; } eoc_needed = 0; break; } if (!asn1_item_d2i(&aval, &cbs_object_content, at->item, -1, 0, 0, depth)) { ASN1error(ERR_R_NESTED_ASN1_ERROR); goto err; } if (!sk_ASN1_VALUE_push(avals, aval)) { ASN1error(ERR_R_MALLOC_FAILURE); goto err; } aval = NULL; } if (eoc_needed) { ASN1error(ASN1_R_MISSING_EOC); goto err; } if (indefinite) { if (!CBS_skip(&cbs_object, CBS_offset(&cbs_object_content))) goto err; } if (!CBS_skip(cbs, CBS_offset(&cbs_object))) goto err; *pval = (ASN1_VALUE *)avals; avals = NULL; return 1; err: asn1_template_stack_of_free(avals, at); ASN1_item_ex_free(&aval, at->item); return 0; } static int asn1_template_noexp_d2i(ASN1_VALUE **pval, CBS *cbs, const ASN1_TEMPLATE *at, int optional, int depth) { int tag_number, tag_class; int ret; if (pval == NULL) return 0; if ((at->flags & ASN1_TFLG_SK_MASK) != 0) return asn1_template_stack_of_d2i(pval, cbs, at, optional, depth); tag_number = -1; tag_class = V_ASN1_UNIVERSAL; /* See if we need to use IMPLICIT tagging. */ if ((at->flags & ASN1_TFLG_IMPTAG) != 0) { tag_number = at->tag; tag_class = at->flags & ASN1_TFLG_TAG_CLASS; } ret = asn1_item_d2i(pval, cbs, at->item, tag_number, tag_class, optional, depth); if (ret == -1) return -1; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); goto err; } return 1; err: /* XXX - The called function should have freed already. */ ASN1_template_free(pval, at); return 0; } static int asn1_template_d2i(ASN1_VALUE **pval, CBS *cbs, const ASN1_TEMPLATE *at, int optional, int depth) { CBS cbs_exp, cbs_exp_content; int constructed, indefinite; size_t length; int ret; if (pval == NULL) return 0; /* Check if EXPLICIT tag is expected. */ if ((at->flags & ASN1_TFLG_EXPTAG) == 0) return asn1_template_noexp_d2i(pval, cbs, at, optional, depth); CBS_init(&cbs_exp, CBS_data(cbs), CBS_len(cbs)); /* Read ASN.1 header for EXPLICIT tagged object. */ ret = asn1_check_tag(&cbs_exp, &length, NULL, NULL, &indefinite, &constructed, at->tag, at->flags & ASN1_TFLG_TAG_CLASS, optional); if (ret == -1) return -1; if (ret != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (!constructed) { ASN1error(ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED); return 0; } if (indefinite) { CBS_init(&cbs_exp_content, CBS_data(&cbs_exp), CBS_len(&cbs_exp)); } else { if (!CBS_get_bytes(&cbs_exp, &cbs_exp_content, length)) goto err; } if ((ret = asn1_template_noexp_d2i(pval, &cbs_exp_content, at, 0, depth)) != 1) { ASN1error(ERR_R_NESTED_ASN1_ERROR); return 0; } if (indefinite) { if (!asn1_check_eoc(&cbs_exp_content)) { ASN1error(ASN1_R_MISSING_EOC); goto err; } if (!CBS_skip(&cbs_exp, CBS_offset(&cbs_exp_content))) goto err; } else if (CBS_len(&cbs_exp_content) != 0) { ASN1error(ASN1_R_SEQUENCE_LENGTH_MISMATCH); goto err; } if (!CBS_skip(cbs, CBS_offset(&cbs_exp))) goto err; return 1; err: ASN1_template_free(pval, at); return 0; } ASN1_VALUE * ASN1_item_d2i(ASN1_VALUE **pval, const unsigned char **in, long inlen, const ASN1_ITEM *it) { ASN1_VALUE *ptmpval = NULL; if (pval == NULL) pval = &ptmpval; if (ASN1_item_ex_d2i(pval, in, inlen, it, -1, 0, 0, NULL) <= 0) return NULL; return *pval; } int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long inlen, const ASN1_ITEM *it, int tag_number, int tag_class, char optional, ASN1_TLC *ctx) { CBS cbs; int ret; if (inlen < 0) return 0; CBS_init(&cbs, *in, inlen); if ((ret = asn1_item_d2i(pval, &cbs, it, tag_number, tag_class, (int)optional, 0)) == 1) *in = CBS_data(&cbs); return ret; } int ASN1_template_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, const ASN1_TEMPLATE *at) { CBS cbs; int ret; if (len < 0) return 0; CBS_init(&cbs, *in, len); if ((ret = asn1_template_d2i(pval, &cbs, at, 0, 0)) == 1) *in = CBS_data(&cbs); return ret; }