diff options
Diffstat (limited to 'openssl-1.1.0h/crypto/asn1/tasn_dec.c')
| -rw-r--r-- | openssl-1.1.0h/crypto/asn1/tasn_dec.c | 1159 |
1 files changed, 1159 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/asn1/tasn_dec.c b/openssl-1.1.0h/crypto/asn1/tasn_dec.c new file mode 100644 index 0000000..af8641e --- /dev/null +++ b/openssl-1.1.0h/crypto/asn1/tasn_dec.c @@ -0,0 +1,1159 @@ +/* + * Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#include <stddef.h> +#include <string.h> +#include <openssl/asn1.h> +#include <openssl/asn1t.h> +#include <openssl/objects.h> +#include <openssl/buffer.h> +#include <openssl/err.h> +#include "internal/numbers.h" +#include "asn1_locl.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. This is the maximum number of + * recursive invocations of asn1_item_embed_d2i(). + */ +#define ASN1_MAX_CONSTRUCTED_NEST 30 + +static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in, + long len, const ASN1_ITEM *it, + int tag, int aclass, char opt, ASN1_TLC *ctx, + int depth); + +static int asn1_check_eoc(const unsigned char **in, long len); +static int asn1_find_end(const unsigned char **in, long len, char inf); + +static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, + char inf, int tag, int aclass, int depth); + +static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen); + +static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, + char *inf, char *cst, + const unsigned char **in, long len, + int exptag, int expclass, char opt, ASN1_TLC *ctx); + +static int asn1_template_ex_d2i(ASN1_VALUE **pval, + const unsigned char **in, long len, + const ASN1_TEMPLATE *tt, char opt, + ASN1_TLC *ctx, int depth); +static int asn1_template_noexp_d2i(ASN1_VALUE **val, + const unsigned char **in, long len, + const ASN1_TEMPLATE *tt, char opt, + ASN1_TLC *ctx, int depth); +static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, + const unsigned char **in, long len, + const ASN1_ITEM *it, + int tag, int aclass, char opt, + ASN1_TLC *ctx); +static int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, + int utype, char *free_cont, const ASN1_ITEM *it); + +/* Table to convert tags to bit values, used for MSTRING type */ +static const unsigned long tag2bit[32] = { + /* tags 0 - 3 */ + 0, 0, 0, B_ASN1_BIT_STRING, + /* tags 4- 7 */ + B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN, + /* tags 8-11 */ + B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, + /* tags 12-15 */ + B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, + /* tags 16-19 */ + B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING, + /* tags 20-22 */ + B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING, + /* tags 23-24 */ + B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, + /* tags 25-27 */ + B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING, + /* tags 28-31 */ + B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN, +}; + +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 +/* Version to avoid compiler warning about 'c' always non-NULL */ +#define asn1_tlc_clear_nc(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, + const unsigned char **in, long len, + const ASN1_ITEM *it) +{ + ASN1_TLC c; + ASN1_VALUE *ptmpval = NULL; + if (!pval) + pval = &ptmpval; + asn1_tlc_clear_nc(&c); + if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) + return *pval; + return NULL; +} + +int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, + const ASN1_ITEM *it, + int tag, int aclass, char opt, ASN1_TLC *ctx) +{ + int rv; + rv = asn1_item_embed_d2i(pval, in, len, it, tag, aclass, opt, ctx, 0); + if (rv <= 0) + ASN1_item_ex_free(pval, it); + return rv; +} + +/* + * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and + * tag mismatch return -1 to handle OPTIONAL + */ + +static int asn1_item_embed_d2i(ASN1_VALUE **pval, const unsigned char **in, + long len, const ASN1_ITEM *it, + int tag, int aclass, char opt, ASN1_TLC *ctx, + int depth) +{ + const ASN1_TEMPLATE *tt, *errtt = NULL; + const ASN1_EXTERN_FUNCS *ef; + const ASN1_AUX *aux = it->funcs; + ASN1_aux_cb *asn1_cb; + const unsigned char *p = NULL, *q; + unsigned char oclass; + char seq_eoc, seq_nolen, cst, isopt; + long tmplen; + int i; + int otag; + int ret = 0; + ASN1_VALUE **pchptr; + if (!pval) + return 0; + if (aux && aux->asn1_cb) + asn1_cb = aux->asn1_cb; + else + asn1_cb = 0; + + if (++depth > ASN1_MAX_CONSTRUCTED_NEST) { + ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ASN1_R_NESTED_TOO_DEEP); + goto err; + } + + 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_EMBED_D2I, + ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); + goto err; + } + return asn1_template_ex_d2i(pval, in, len, + it->templates, opt, ctx, depth); + } + return asn1_d2i_ex_primitive(pval, in, len, it, + tag, aclass, opt, ctx); + + 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_EMBED_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_EMBED_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_EMBED_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_CHOICE: + if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL)) + goto auxerr; + if (*pval) { + /* Free up and zero CHOICE value if initialised */ + i = asn1_get_choice_selector(pval, it); + if ((i >= 0) && (i < it->tcount)) { + tt = it->templates + i; + pchptr = asn1_get_field_ptr(pval, tt); + asn1_template_free(pchptr, tt); + asn1_set_choice_selector(pval, -1, it); + } + } else if (!ASN1_item_ex_new(pval, it)) { + ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ERR_R_NESTED_ASN1_ERROR); + goto err; + } + /* CHOICE type, try each possibility in turn */ + 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, depth); + /* If field not present, try the next one */ + if (ret == -1) + continue; + /* If positive return, read OK, break loop */ + if (ret > 0) + break; + /* + * Must be an ASN1 parsing error. + * Free up any partial choice value + */ + asn1_template_free(pchptr, tt); + errtt = tt; + ASN1err(ASN1_F_ASN1_ITEM_EMBED_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_EMBED_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE); + goto err; + } + + asn1_set_choice_selector(pval, i, it); + + if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL)) + goto auxerr; + *in = p; + return 1; + + case ASN1_ITYPE_NDEF_SEQUENCE: + 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_EMBED_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; + } + /* If indefinite we don't do a length check */ + else + seq_nolen = seq_eoc; + if (!cst) { + ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED); + goto err; + } + + if (!*pval && !ASN1_item_ex_new(pval, it)) { + ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ERR_R_NESTED_ASN1_ERROR); + goto err; + } + + if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL)) + goto auxerr; + + /* Free up and zero any ADB found */ + for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { + if (tt->flags & ASN1_TFLG_ADB_MASK) { + const ASN1_TEMPLATE *seqtt; + ASN1_VALUE **pseqval; + seqtt = asn1_do_adb(pval, tt, 0); + if (seqtt == NULL) + continue; + pseqval = asn1_get_field_ptr(pval, seqtt); + asn1_template_free(pseqval, seqtt); + } + } + + /* 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 == NULL) + 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_EMBED_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, + depth); + 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_EMBED_D2I, ASN1_R_MISSING_EOC); + goto err; + } + /* Check all data read */ + if (!seq_nolen && len) { + ASN1err(ASN1_F_ASN1_ITEM_EMBED_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 == NULL) + 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_EMBED_D2I, ASN1_R_FIELD_MISSING); + goto err; + } + } + /* Save encoding */ + if (!asn1_enc_save(pval, *in, p - *in, it)) + goto auxerr; + if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL)) + goto auxerr; + *in = p; + return 1; + + default: + return 0; + } + auxerr: + ASN1err(ASN1_F_ASN1_ITEM_EMBED_D2I, ASN1_R_AUX_ERROR); + err: + 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, + const unsigned char **in, long inlen, + const ASN1_TEMPLATE *tt, char opt, + ASN1_TLC *ctx, int depth) +{ + int flags, aclass; + int ret; + long len; + const 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, depth); + 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_EX_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_EX_D2I, + ASN1_R_EXPLICIT_LENGTH_MISMATCH); + goto err; + } + } + } else + return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx, depth); + + *in = p; + return 1; + + err: + return 0; +} + +static int asn1_template_noexp_d2i(ASN1_VALUE **val, + const unsigned char **in, long len, + const ASN1_TEMPLATE *tt, char opt, + ASN1_TLC *ctx, int depth) +{ + int flags, aclass; + int ret; + ASN1_VALUE *tval; + const unsigned char *p, *q; + if (!val) + return 0; + flags = tt->flags; + aclass = flags & ASN1_TFLG_TAG_CLASS; + + p = *in; + q = p; + + /* + * If field is embedded then val needs fixing so it is a pointer to + * a pointer to a field. + */ + if (tt->flags & ASN1_TFLG_EMBED) { + tval = (ASN1_VALUE *)val; + val = &tval; + } + + 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_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); + return 0; + } else if (ret == -1) + return -1; + if (!*val) + *val = (ASN1_VALUE *)OPENSSL_sk_new_null(); + else { + /* + * We've got a valid STACK: free up any items present + */ + STACK_OF(ASN1_VALUE) *sktmp = (STACK_OF(ASN1_VALUE) *)*val; + ASN1_VALUE *vtmp; + while (sk_ASN1_VALUE_num(sktmp) > 0) { + vtmp = sk_ASN1_VALUE_pop(sktmp); + ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item)); + } + } + + if (!*val) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_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_NOEXP_D2I, + ASN1_R_UNEXPECTED_EOC); + goto err; + } + len -= p - q; + sk_eoc = 0; + break; + } + skfield = NULL; + if (!asn1_item_embed_d2i(&skfield, &p, len, + ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx, + depth)) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, + ERR_R_NESTED_ASN1_ERROR); + /* |skfield| may be partially allocated despite failure. */ + ASN1_item_free(skfield, ASN1_ITEM_ptr(tt->item)); + goto err; + } + len -= p - q; + if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val, skfield)) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE); + ASN1_item_free(skfield, ASN1_ITEM_ptr(tt->item)); + goto err; + } + } + if (sk_eoc) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC); + goto err; + } + } else if (flags & ASN1_TFLG_IMPTAG) { + /* IMPLICIT tagging */ + ret = asn1_item_embed_d2i(val, &p, len, + ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, + ctx, depth); + if (!ret) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); + goto err; + } else if (ret == -1) + return -1; + } else { + /* Nothing special */ + ret = asn1_item_embed_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), + -1, 0, opt, ctx, depth); + if (!ret) { + ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); + goto err; + } else if (ret == -1) + return -1; + } + + *in = p; + return 1; + + err: + return 0; +} + +static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, + const 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; + const unsigned char *p; + BUF_MEM buf = { 0, NULL, 0, 0 }; + const 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 won't 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; + } + } else if (cst) { + if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN + || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER + || utype == V_ASN1_ENUMERATED) { + ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE); + return 0; + } + + /* Free any returned 'buf' content */ + free_cont = 1; + /* + * 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, 0)) { + 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); + goto err; + } + buf.data[len] = 0; + cont = (const unsigned char *)buf.data; + } else { + cont = p; + len = plen; + p += plen; + } + + /* We now have content length and type: translate into a structure */ + /* asn1_ex_c2i may reuse allocated buffer, and so sets free_cont to 0 */ + if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) + goto err; + + *in = p; + ret = 1; + err: + if (free_cont) + OPENSSL_free(buf.data); + return ret; +} + +/* Translate ASN1 content octets into a structure */ + +static int asn1_ex_c2i(ASN1_VALUE **pval, const 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(); + if (typ == NULL) + goto err; + *pval = (ASN1_VALUE *)typ; + } else + typ = (ASN1_TYPE *)*pval; + + if (utype != typ->type) + ASN1_TYPE_set(typ, utype, NULL); + opval = pval; + pval = &typ->value.asn1_value; + } + 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_EX_C2I, ASN1_R_NULL_IS_WRONG_LENGTH); + goto err; + } + *pval = (ASN1_VALUE *)1; + break; + + case V_ASN1_BOOLEAN: + if (len != 1) { + ASN1err(ASN1_F_ASN1_EX_C2I, 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_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: + if (utype == V_ASN1_BMPSTRING && (len & 1)) { + ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BMPSTRING_IS_WRONG_LENGTH); + goto err; + } + if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) { + ASN1err(ASN1_F_ASN1_EX_C2I, + ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH); + goto err; + } + /* All based on ASN1_STRING and handled the same */ + if (!*pval) { + stmp = ASN1_STRING_type_new(utype); + if (stmp == NULL) { + ASN1err(ASN1_F_ASN1_EX_C2I, 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) { + OPENSSL_free(stmp->data); + stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */ + stmp->length = len; + *free_cont = 0; + } else { + if (!ASN1_STRING_set(stmp, cont, len)) { + ASN1err(ASN1_F_ASN1_EX_C2I, 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(const unsigned char **in, long len, char inf) +{ + uint32_t expected_eoc; + long plen; + const 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 just 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) { + if (expected_eoc == UINT32_MAX) { + ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR); + return 0; + } + 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 constructed 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. + */ + +#ifndef ASN1_MAX_STRING_NEST +/* + * This determines how many levels of recursion are permitted in ASN1 string + * types. If it is not limited stack overflows can occur. If set to zero no + * recursion is allowed at all. Although zero should be adequate examples + * exist that require a value of 1. So 5 should be more than enough. + */ +# define ASN1_MAX_STRING_NEST 5 +#endif + +static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, + char inf, int tag, int aclass, int depth) +{ + const unsigned char *p, *q; + long plen; + char cst, ininf; + p = *in; + inf &= 1; + /* + * If no buffer and not indefinite length constructed just pass over the + * encoded data + */ + if (!buf && !inf) { + *in += len; + return 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) { + if (depth >= ASN1_MAX_STRING_NEST) { + ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING); + return 0; + } + if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1)) + return 0; + } 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, const 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(const unsigned char **in, long len) +{ + const 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, + const unsigned char **in, long len, + int exptag, int expclass, char opt, ASN1_TLC *ctx) +{ + int i; + int ptag, pclass; + long plen; + const 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: 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: 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; +} |