/* tasn_dec.c */ /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL * project 2000. */ /* ==================================================================== * Copyright (c) 2000 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 static int asn1_check_eoc(unsigned char **in, long len); static int asn1_find_end(unsigned char **in, long len, char inf); static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass); static int collect_data(BUF_MEM *buf, unsigned char **p, long plen); static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst, unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx); static int asn1_template_ex_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx); static int asn1_template_noexp_d2i(ASN1_VALUE **val, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx); static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx); /* Table to convert tags to bit values, used for MSTRING type */ static unsigned long tag2bit[32]={ 0, 0, 0, B_ASN1_BIT_STRING, /* tags 0 - 3 */ B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,/* tags 4- 7 */ B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags 8-11 */ B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */ 0, 0, B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */ B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING, /* tags 20-22 */ B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, /* tags 23-24 */ B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING, /* tags 25-27 */ B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */ }; unsigned long ASN1_tag2bit(int tag) { if((tag < 0) || (tag > 30)) return 0; return tag2bit[tag]; } /* Macro to initialize and invalidate the cache */ #define asn1_tlc_clear(c) if(c) (c)->valid = 0 /* Decode an ASN1 item, this currently behaves just * like a standard 'd2i' function. 'in' points to * a buffer to read the data from, in future we will * have more advanced versions that can input data * a piece at a time and this will simply be a special * case. */ ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_ITEM *it) { ASN1_TLC c; ASN1_VALUE *ptmpval = NULL; if(!pval) pval = &ptmpval; asn1_tlc_clear(&c); if(ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) return *pval; return NULL; } int ASN1_template_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_TEMPLATE *tt) { ASN1_TLC c; asn1_tlc_clear(&c); return asn1_template_ex_d2i(pval, in, len, tt, 0, &c); } /* Decode an item, taking care of IMPLICIT tagging, if any. * If 'opt' set and tag mismatch return -1 to handle OPTIONAL */ int ASN1_item_ex_d2i(ASN1_VALUE **pval, unsigned char **in, long len, const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx) { const ASN1_TEMPLATE *tt, *errtt = NULL; const ASN1_COMPAT_FUNCS *cf; const ASN1_EXTERN_FUNCS *ef; const ASN1_AUX *aux = it->funcs; ASN1_aux_cb *asn1_cb; unsigned char *p, *q, imphack = 0, oclass; char seq_eoc, seq_nolen, cst, isopt; long tmplen; int i; int otag; int ret = 0; ASN1_VALUE *pchval, **pchptr, *ptmpval; if(!pval) return 0; if(aux && aux->asn1_cb) asn1_cb = aux->asn1_cb; else asn1_cb = 0; switch(it->itype) { case ASN1_ITYPE_PRIMITIVE: if(it->templates) { /* 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 != -1) || opt) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); goto err; } return asn1_template_ex_d2i(pval, in, len, it->templates, opt, ctx); } return asn1_d2i_ex_primitive(pval, in, len, it, tag, aclass, opt, ctx); break; case ASN1_ITYPE_MSTRING: p = *in; /* Just read in tag and class */ ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, &p, len, -1, 0, 1, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } /* Must be UNIVERSAL class */ if(oclass != V_ASN1_UNIVERSAL) { /* If OPTIONAL, assume this is OK */ if(opt) return -1; ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL); goto err; } /* Check tag matches bit map */ if(!(ASN1_tag2bit(otag) & it->utype)) { /* If OPTIONAL, assume this is OK */ if(opt) return -1; ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG); goto err; } return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx); case ASN1_ITYPE_EXTERN: /* Use new style d2i */ ef = it->funcs; return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx); case ASN1_ITYPE_COMPAT: /* we must resort to old style evil hackery */ cf = it->funcs; /* If OPTIONAL see if it is there */ if(opt) { int exptag; p = *in; if(tag == -1) exptag = it->utype; else exptag = tag; /* Don't care about anything other than presence of expected tag */ ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, &p, len, exptag, aclass, 1, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } if(ret == -1) return -1; } /* This is the old style evil hack IMPLICIT handling: * since the underlying code is expecting a tag and * class other than the one present we change the * buffer temporarily then change it back afterwards. * This doesn't and never did work for tags > 30. * * Yes this is *horrible* but it is only needed for * old style d2i which will hopefully not be around * for much longer. * FIXME: should copy the buffer then modify it so * the input buffer can be const: we should *always* * copy because the old style d2i might modify the * buffer. */ if(tag != -1) { p = *in; imphack = *p; *p = (unsigned char)((*p & V_ASN1_CONSTRUCTED) | it->utype); } ptmpval = cf->asn1_d2i(pval, in, len); if(tag != -1) *p = imphack; if(ptmpval) return 1; ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; case ASN1_ITYPE_CHOICE: if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) goto auxerr; /* Allocate structure */ if(!*pval) { if(!ASN1_item_ex_new(pval, it)) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } } /* CHOICE type, try each possibility in turn */ pchval = NULL; p = *in; for(i = 0, tt=it->templates; i < it->tcount; i++, tt++) { pchptr = asn1_get_field_ptr(pval, tt); /* We mark field as OPTIONAL so its absence * can be recognised. */ ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx); /* If field not present, try the next one */ if(ret == -1) continue; /* If positive return, read OK, break loop */ if(ret > 0) break; /* Otherwise must be an ASN1 parsing error */ errtt = tt; ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } /* Did we fall off the end without reading anything? */ if(i == it->tcount) { /* If OPTIONAL, this is OK */ if(opt) { /* Free and zero it */ ASN1_item_ex_free(pval, it); return -1; } ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE); goto err; } asn1_set_choice_selector(pval, i, it); *in = p; if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) goto auxerr; return 1; case ASN1_ITYPE_SEQUENCE: p = *in; tmplen = len; /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */ if(tag == -1) { tag = V_ASN1_SEQUENCE; aclass = V_ASN1_UNIVERSAL; } /* Get SEQUENCE length and update len, p */ ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst, &p, len, tag, aclass, opt, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } else if(ret == -1) return -1; if(aux && (aux->flags & ASN1_AFLG_BROKEN)) { len = tmplen - (p - *in); seq_nolen = 1; } else seq_nolen = seq_eoc; /* If indefinite we don't do a length check */ if(!cst) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED); goto err; } if(!*pval) { if(!ASN1_item_ex_new(pval, it)) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } } if(asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) goto auxerr; /* Get each field entry */ for(i = 0, tt = it->templates; i < it->tcount; i++, tt++) { const ASN1_TEMPLATE *seqtt; ASN1_VALUE **pseqval; seqtt = asn1_do_adb(pval, tt, 1); if(!seqtt) goto err; pseqval = asn1_get_field_ptr(pval, seqtt); /* Have we ran out of data? */ if(!len) break; q = p; if(asn1_check_eoc(&p, len)) { if(!seq_eoc) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC); goto err; } len -= p - q; seq_eoc = 0; q = p; break; } /* This determines the OPTIONAL flag value. The field cannot * be omitted if it is the last of a SEQUENCE and there is * still data to be read. This isn't strictly necessary but * it increases efficiency in some cases. */ if(i == (it->tcount - 1)) isopt = 0; else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL); /* attempt to read in field, allowing each to be OPTIONAL */ ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx); if(!ret) { errtt = seqtt; goto err; } else if(ret == -1) { /* OPTIONAL component absent. Free and zero the field */ ASN1_template_free(pseqval, seqtt); continue; } /* Update length */ len -= p - q; } /* Check for EOC if expecting one */ if(seq_eoc && !asn1_check_eoc(&p, len)) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC); goto err; } /* Check all data read */ if(!seq_nolen && len) { ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH); goto err; } /* If we get here we've got no more data in the SEQUENCE, * however we may not have read all fields so check all * remaining are OPTIONAL and clear any that are. */ for(; i < it->tcount; tt++, i++) { const ASN1_TEMPLATE *seqtt; seqtt = asn1_do_adb(pval, tt, 1); if(!seqtt) goto err; if(seqtt->flags & ASN1_TFLG_OPTIONAL) { ASN1_VALUE **pseqval; pseqval = asn1_get_field_ptr(pval, seqtt); ASN1_template_free(pseqval, seqtt); } else { errtt = seqtt; ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING); goto err; } } /* Save encoding */ if(!asn1_enc_save(pval, *in, p - *in, it)) goto auxerr; *in = p; if(asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) goto auxerr; return 1; default: return 0; } auxerr: ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR); err: ASN1_item_ex_free(pval, it); if(errtt) ERR_add_error_data(4, "Field=", errtt->field_name, ", Type=", it->sname); else ERR_add_error_data(2, "Type=", it->sname); return 0; } /* Templates are handled with two separate functions. One handles any EXPLICIT tag and the other handles the * rest. */ static int asn1_template_ex_d2i(ASN1_VALUE **val, unsigned char **in, long inlen, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx) { int flags, aclass; int ret; long len; unsigned char *p, *q; char exp_eoc; if(!val) return 0; flags = tt->flags; aclass = flags & ASN1_TFLG_TAG_CLASS; p = *in; /* Check if EXPLICIT tag expected */ if(flags & ASN1_TFLG_EXPTAG) { char cst; /* Need to work out amount of data available to the inner content and where it * starts: so read in EXPLICIT header to get the info. */ ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, &p, inlen, tt->tag, aclass, opt, ctx); q = p; if(!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); return 0; } else if(ret == -1) return -1; if(!cst) { ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED); return 0; } /* We've found the field so it can't be OPTIONAL now */ ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); return 0; } /* We read the field in OK so update length */ len -= p - q; if(exp_eoc) { /* If NDEF we must have an EOC here */ if(!asn1_check_eoc(&p, len)) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC); goto err; } } else { /* Otherwise we must hit the EXPLICIT tag end or its an error */ if(len) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_EXPLICIT_LENGTH_MISMATCH); goto err; } } } else return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx); *in = p; return 1; err: ASN1_template_free(val, tt); *val = NULL; return 0; } static int asn1_template_noexp_d2i(ASN1_VALUE **val, unsigned char **in, long len, const ASN1_TEMPLATE *tt, char opt, ASN1_TLC *ctx) { int flags, aclass; int ret; unsigned char *p, *q; if(!val) return 0; flags = tt->flags; aclass = flags & ASN1_TFLG_TAG_CLASS; p = *in; q = p; if(flags & ASN1_TFLG_SK_MASK) { /* SET OF, SEQUENCE OF */ int sktag, skaclass; char sk_eoc; /* First work out expected inner tag value */ if(flags & ASN1_TFLG_IMPTAG) { sktag = tt->tag; skaclass = aclass; } else { skaclass = V_ASN1_UNIVERSAL; if(flags & ASN1_TFLG_SET_OF) sktag = V_ASN1_SET; else sktag = V_ASN1_SEQUENCE; } /* Get the tag */ ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, &p, len, sktag, skaclass, opt, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); return 0; } else if(ret == -1) return -1; if(!*val) *val = (ASN1_VALUE *)sk_new_null(); else { /* We've got a valid STACK: free up any items present */ STACK *sktmp = (STACK *)*val; ASN1_VALUE *vtmp; while(sk_num(sktmp) > 0) { vtmp = (ASN1_VALUE *)sk_pop(sktmp); ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item)); } } if(!*val) { ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_MALLOC_FAILURE); goto err; } /* Read as many items as we can */ while(len > 0) { ASN1_VALUE *skfield; q = p; /* See if EOC found */ if(asn1_check_eoc(&p, len)) { if(!sk_eoc) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_UNEXPECTED_EOC); goto err; } len -= p - q; sk_eoc = 0; break; } skfield = NULL; if(!ASN1_item_ex_d2i(&skfield, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } len -= p - q; if(!sk_push((STACK *)*val, (char *)skfield)) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_MALLOC_FAILURE); goto err; } } if(sk_eoc) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC); goto err; } } else if(flags & ASN1_TFLG_IMPTAG) { /* IMPLICIT tagging */ ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } else if(ret == -1) return -1; } else { /* Nothing special */ ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), -1, 0, opt, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ERR_R_NESTED_ASN1_ERROR); goto err; } else if(ret == -1) return -1; } *in = p; return 1; err: ASN1_template_free(val, tt); *val = NULL; return 0; } static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, unsigned char **in, long inlen, const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx) { int ret = 0, utype; long plen; char cst, inf, free_cont = 0; unsigned char *p; BUF_MEM buf; unsigned char *cont = NULL; long len; if(!pval) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL); return 0; /* Should never happen */ } if(it->itype == ASN1_ITYPE_MSTRING) { utype = tag; tag = -1; } else utype = it->utype; if(utype == V_ASN1_ANY) { /* If type is ANY need to figure out type from tag */ unsigned char oclass; if(tag >= 0) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY); return 0; } if(opt) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_OPTIONAL_ANY); return 0; } p = *in; ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, &p, inlen, -1, 0, 0, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); return 0; } if(oclass != V_ASN1_UNIVERSAL) utype = V_ASN1_OTHER; } if(tag == -1) { tag = utype; aclass = V_ASN1_UNIVERSAL; } p = *in; /* Check header */ ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, &p, inlen, tag, aclass, opt, ctx); if(!ret) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); return 0; } else if(ret == -1) return -1; ret = 0; /* SEQUENCE, SET and "OTHER" are left in encoded form */ if((utype == V_ASN1_SEQUENCE) || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) { /* Clear context cache for type OTHER because the auto clear when * we have a exact match wont work */ if(utype == V_ASN1_OTHER) { asn1_tlc_clear(ctx); /* SEQUENCE and SET must be constructed */ } else if(!cst) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_CONSTRUCTED); return 0; } cont = *in; /* If indefinite length constructed find the real end */ if(inf) { if(!asn1_find_end(&p, plen, inf)) goto err; len = p - cont; } else { len = p - cont + plen; p += plen; buf.data = NULL; } } else if(cst) { buf.length = 0; buf.max = 0; buf.data = NULL; /* 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(!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL)) goto err; len = buf.length; /* Append a final null to string */ if(!BUF_MEM_grow_clean(&buf, len + 1)) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE); return 0; } buf.data[len] = 0; cont = (unsigned char *)buf.data; free_cont = 1; } else { cont = p; len = plen; p += plen; } /* We now have content length and type: translate into a structure */ if(!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) goto err; *in = p; ret = 1; err: if(free_cont && buf.data) OPENSSL_free(buf.data); return ret; } /* Translate ASN1 content octets into a structure */ int asn1_ex_c2i(ASN1_VALUE **pval, unsigned char *cont, int len, int utype, char *free_cont, const ASN1_ITEM *it) { ASN1_VALUE **opval = NULL; ASN1_STRING *stmp; ASN1_TYPE *typ = NULL; int ret = 0; const ASN1_PRIMITIVE_FUNCS *pf; ASN1_INTEGER **tint; pf = it->funcs; if(pf && pf->prim_c2i) return pf->prim_c2i(pval, cont, len, utype, free_cont, it); /* If ANY type clear type and set pointer to internal value */ if(it->utype == V_ASN1_ANY) { if(!*pval) { typ = ASN1_TYPE_new(); *pval = (ASN1_VALUE *)typ; } else typ = (ASN1_TYPE *)*pval; if(utype != typ->type) ASN1_TYPE_set(typ, utype, NULL); opval = pval; pval = (ASN1_VALUE **)&typ->value.ptr; } switch(utype) { case V_ASN1_OBJECT: if(!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) goto err; break; case V_ASN1_NULL: if(len) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_NULL_IS_WRONG_LENGTH); goto err; } *pval = (ASN1_VALUE *)1; break; case V_ASN1_BOOLEAN: if(len != 1) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_BOOLEAN_IS_WRONG_LENGTH); goto err; } else { ASN1_BOOLEAN *tbool; tbool = (ASN1_BOOLEAN *)pval; *tbool = *cont; } break; case V_ASN1_BIT_STRING: if(!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) goto err; break; case V_ASN1_INTEGER: case V_ASN1_NEG_INTEGER: case V_ASN1_ENUMERATED: case V_ASN1_NEG_ENUMERATED: tint = (ASN1_INTEGER **)pval; if(!c2i_ASN1_INTEGER(tint, &cont, len)) goto err; /* Fixup type to match the expected form */ (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG); 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: /* All based on ASN1_STRING and handled the same */ if(!*pval) { stmp = ASN1_STRING_type_new(utype); if(!stmp) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE); goto err; } *pval = (ASN1_VALUE *)stmp; } else { stmp = (ASN1_STRING *)*pval; stmp->type = utype; } /* If we've already allocated a buffer use it */ if(*free_cont) { if(stmp->data) OPENSSL_free(stmp->data); stmp->data = cont; stmp->length = len; *free_cont = 0; } else { if(!ASN1_STRING_set(stmp, cont, len)) { ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE); ASN1_STRING_free(stmp); *pval = NULL; goto err; } } break; } /* If ASN1_ANY and NULL type fix up value */ if(typ && utype==V_ASN1_NULL) typ->value.ptr = NULL; ret = 1; err: if(!ret) { ASN1_TYPE_free(typ); if (opval) *opval = NULL; } return ret; } /* This function finds the end of an ASN1 structure when passed its maximum * length, whether it is indefinite length and a pointer to the content. * This is more efficient than calling asn1_collect because it does not * recurse on each indefinite length header. */ static int asn1_find_end(unsigned char **in, long len, char inf) { int expected_eoc; long plen; unsigned char *p = *in, *q; /* If not indefinite length constructed just add length */ if (inf == 0) { *in += len; return 1; } expected_eoc = 1; /* Indefinite length constructed form. Find the end when enough EOCs * are found. If more indefinite length constructed headers * are encountered increment the expected eoc count otherwise justi * skip to the end of the data. */ while (len > 0) { if(asn1_check_eoc(&p, len)) { expected_eoc--; if (expected_eoc == 0) break; len -= 2; continue; } q = p; /* Just read in a header: only care about the length */ if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len, -1, 0, 0, NULL)) { ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR); return 0; } if (inf) expected_eoc++; else p += plen; len -= p - q; } if (expected_eoc) { ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC); return 0; } *in = p; return 1; } /* This function collects the asn1 data from a constructred string * type into a buffer. The values of 'in' and 'len' should refer * to the contents of the constructed type and 'inf' should be set * if it is indefinite length. */ static int asn1_collect(BUF_MEM *buf, unsigned char **in, long len, char inf, int tag, int aclass) { unsigned char *p, *q; long plen; char cst, ininf; p = *in; inf &= 1; while(len > 0) { q = p; /* Check for EOC */ if(asn1_check_eoc(&p, len)) { /* EOC is illegal outside indefinite length constructed form */ if(!inf) { ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC); return 0; } inf = 0; break; } if(!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, len, tag, aclass, 0, NULL)) { ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR); return 0; } /* If indefinite length constructed update max length */ if(cst) { #ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS if (!asn1_collect(buf, &p, plen, ininf, tag, aclass)) return 0; #else ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING); return 0; #endif } else { if(plen && !collect_data(buf, &p, plen)) return 0; } len -= p - q; } if(inf) { ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC); return 0; } *in = p; return 1; } static int collect_data(BUF_MEM *buf, unsigned char **p, long plen) { int len; if(buf) { len = buf->length; if(!BUF_MEM_grow_clean(buf, len + plen)) { ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE); return 0; } memcpy(buf->data + len, *p, plen); } *p += plen; return 1; } /* Check for ASN1 EOC and swallow it if found */ static int asn1_check_eoc(unsigned char **in, long len) { unsigned char *p; if(len < 2) return 0; p = *in; if(!p[0] && !p[1]) { *in += 2; return 1; } return 0; } /* Check an ASN1 tag and length: a bit like ASN1_get_object * but it sets the length for indefinite length constructed * form, we don't know the exact length but we can set an * upper bound to the amount of data available minus the * header length just read. */ static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, char *inf, char *cst, unsigned char **in, long len, int exptag, int expclass, char opt, ASN1_TLC *ctx) { int i; int ptag, pclass; long plen; unsigned char *p, *q; p = *in; q = p; if(ctx && ctx->valid) { i = ctx->ret; plen = ctx->plen; pclass = ctx->pclass; ptag = ctx->ptag; p += ctx->hdrlen; } else { i = ASN1_get_object(&p, &plen, &ptag, &pclass, len); if(ctx) { ctx->ret = i; ctx->plen = plen; ctx->pclass = pclass; ctx->ptag = ptag; ctx->hdrlen = p - q; ctx->valid = 1; /* If definite length, and no error, length + * header can't exceed total amount of data available. */ if(!(i & 0x81) && ((plen + ctx->hdrlen) > len)) { ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG); asn1_tlc_clear(ctx); return 0; } } } if(i & 0x80) { ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER); asn1_tlc_clear(ctx); return 0; } if(exptag >= 0) { if((exptag != ptag) || (expclass != pclass)) { /* If type is OPTIONAL, not an error, but indicate missing * type. */ if(opt) return -1; asn1_tlc_clear(ctx); ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG); return 0; } /* We have a tag and class match, so assume we are going to do something with it */ asn1_tlc_clear(ctx); } if(i & 1) plen = len - (p - q); if(inf) *inf = i & 1; if(cst) *cst = i & V_ASN1_CONSTRUCTED; if(olen) *olen = plen; if(oclass) *oclass = pclass; if(otag) *otag = ptag; *in = p; return 1; }