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Diffstat (limited to 'src/VBox/Runtime/common/asn1/asn1-ut-objid-decode.cpp')
| -rw-r--r-- | src/VBox/Runtime/common/asn1/asn1-ut-objid-decode.cpp | 377 |
1 files changed, 377 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/asn1/asn1-ut-objid-decode.cpp b/src/VBox/Runtime/common/asn1/asn1-ut-objid-decode.cpp new file mode 100644 index 00000000..6d0e66a0 --- /dev/null +++ b/src/VBox/Runtime/common/asn1/asn1-ut-objid-decode.cpp @@ -0,0 +1,377 @@ +/* $Id: asn1-ut-objid-decode.cpp $ */ +/** @file + * IPRT - ASN.1, OBJECT IDENTIFIER Type, Decoder. + */ + +/* + * Copyright (C) 2006-2023 Oracle and/or its affiliates. + * + * This file is part of VirtualBox base platform packages, as + * available from https://www.virtualbox.org. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, in version 3 of the + * License. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <https://www.gnu.org/licenses>. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included + * in the VirtualBox distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + * + * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include "internal/iprt.h" +#include <iprt/asn1.h> + +#include <iprt/alloca.h> +#include <iprt/err.h> +#include <iprt/string.h> +#include <iprt/ctype.h> + +#include <iprt/formats/asn1.h> + + +/********************************************************************************************************************************* +* Global Variables * +*********************************************************************************************************************************/ +static char const g_achDigits[11] = "0123456789"; + + +/********************************************************************************************************************************* +* Internal Functions * +*********************************************************************************************************************************/ +DECLHIDDEN(int) rtAsn1ObjId_InternalFormatComponent(uint32_t uValue, char **ppszObjId, size_t *pcbObjId); /* asn1-ut-objid.cpp */ + + +/** + * Internal worker for RTAsn1ObjId_DecodeAsn1 that formats a component, with a + * leading dot. + * + * @returns VBox status code (caller complains on failure). + * @param uValue The component ID value. + * @param ppszObjId Pointer to the output buffer pointer. + * @param pcbObjId Pointer to the remaining size of the output buffer. + */ +DECLHIDDEN(int) rtAsn1ObjId_InternalFormatComponent(uint32_t uValue, char **ppszObjId, size_t *pcbObjId) +{ + /* + * Format the number backwards. + */ + char szTmp[32]; + char *psz = &szTmp[sizeof(szTmp) - 1]; + *psz = '\0'; + + do + { + *--psz = g_achDigits[uValue % 10]; + uValue /= 10; + } while (uValue > 0); + + /* + * Do we have enough space? + * We add a dot and save space for the terminator. + */ + size_t cchNeeded = &szTmp[sizeof(szTmp) - 1] - psz; + if (1 + cchNeeded < *pcbObjId) + { + *pcbObjId -= cchNeeded + 1; + char *pszObjId = *ppszObjId; + *ppszObjId = pszObjId + cchNeeded + 1; + + *pszObjId = '.'; + memcpy(pszObjId + 1, psz, cchNeeded); + return VINF_SUCCESS; + } + + AssertFailed(); + return VERR_ASN1_OBJID_TOO_LONG_STRING_FORM; +} + + +/** + * Reads one object ID component, returning it's value and encoded length. + * + * @returns The encoded length (positive) on success, negative IPRT status code + * on failure. + * @param pbContent The start of the component to parse. + * @param cbContent The number of content bytes left. + * @param puValue Where to return the value. + */ +static int rtAsn1ObjId_ReadComponent(uint8_t const *pbContent, uint32_t cbContent, uint32_t *puValue) +{ + if (cbContent >= 1) + { + /* The first byte. */ + uint8_t b = *pbContent; + if (!(b & 0x80)) + { + *puValue = b; + return 1; + } + + /* Encoded as more than one byte. Make sure that it's efficently + encoded as 8.19.2 indicates it must. */ + if (b != 0x80) + { + uint32_t off = 1; + uint32_t uValue = b & 0x7f; + while (off < cbContent) + { + b = pbContent[off++]; + uValue <<= 7; + uValue |= b & 0x7f; + if (!(b & 0x80)) + { + *puValue = uValue; + return (int)off; + } + + if (RT_UNLIKELY(uValue & UINT32_C(0x0e000000))) + return VERR_ASN1_OBJID_COMPONENT_TOO_BIG; + } + } + return VERR_ASN1_INVALID_OBJID_ENCODING; + } + return VERR_NO_DATA; +} + + +/** + * This function parses the binary content of an OBJECT IDENTIFIER, check the + * encoding as well as calculating the storage requirements. + * + * @returns IPRT status code + * @param pbContent Pointer to the content. + * @param cbContent The length of the content. + * @param pCursor The cursor (for error reporting). + * @param pszErrorTag The error tag. + * @param pcComponents Where to return the component count. + * @param pcchObjId Where to return the length of the dotted string + * representation. + */ +static int rtAsn1ObjId_PreParse(uint8_t const *pbContent, uint32_t cbContent, PRTASN1CURSOR pCursor, const char *pszErrorTag, + uint8_t *pcComponents, uint8_t *pcchObjId) +{ + int rc; + if (cbContent >= 1 && cbContent < _1K) + { + /* + * Decode the first two numbers. Monkey business: X*40 + Y + * Where X is the first number, X in {0,1,2}, and Y is the second + * one. The range of Y is {0,...,39} for X in {0,1}, but has a + * free range for X = 2. + */ + uint32_t cComponents = 1; + uint32_t uValue; + rc = rtAsn1ObjId_ReadComponent(pbContent, cbContent, &uValue); + if (rc > 0) + { + uint32_t cchObjId = 1; + uValue = uValue < 2*40 ? uValue % 40 : uValue - 2*40; /* Y */ + do + { + cComponents++; + + /* Figure the encoded string length, binary search fashion. */ + if (uValue < 10000) + { + if (uValue < 100) + { + if (uValue < 10) + cchObjId += 1 + 1; + else + cchObjId += 1 + 2; + } + else + { + if (uValue < 1000) + cchObjId += 1 + 3; + else + cchObjId += 1 + 4; + } + } + else + { + if (uValue < 1000000) + { + if (uValue < 100000) + cchObjId += 1 + 5; + else + cchObjId += 1 + 6; + } + else + { + if (uValue < 10000000) + cchObjId += 1 + 7; + else if (uValue < 100000000) + cchObjId += 1 + 8; + else + cchObjId += 1 + 9; + } + } + + /* advance. */ + pbContent += rc; + cbContent -= rc; + if (!cbContent) + { + if (cComponents < 128) + { + if (cchObjId < RT_SIZEOFMEMB(RTASN1OBJID, szObjId)) + { + *pcComponents = cComponents; + *pcchObjId = cchObjId; + return VINF_SUCCESS; + } + return RTAsn1CursorSetInfo(pCursor, VERR_ASN1_OBJID_TOO_LONG_STRING_FORM, + "%s: Object ID has a too long string form: %#x (max %#x)", + pszErrorTag, cchObjId, RT_SIZEOFMEMB(RTASN1OBJID, szObjId)); + } + return RTAsn1CursorSetInfo(pCursor, VERR_ASN1_OBJID_TOO_MANY_COMPONENTS, + "%s: Object ID has too many components: %#x (max 127)", pszErrorTag, cComponents); + } + + /* next */ + rc = rtAsn1ObjId_ReadComponent(pbContent, cbContent, &uValue); + } while (rc > 0); + } + rc = RTAsn1CursorSetInfo(pCursor, rc, "%s: Bad object ID component #%u encoding: %.*Rhxs", + pszErrorTag, cComponents, cbContent, pbContent); + } + else if (cbContent) + rc = RTAsn1CursorSetInfo(pCursor, VERR_ASN1_INVALID_OBJID_ENCODING, "%s: Object ID content is loo long: %#x", + pszErrorTag, cbContent); + else + rc = RTAsn1CursorSetInfo(pCursor, VERR_ASN1_INVALID_OBJID_ENCODING, "%s: Zero length object ID content", pszErrorTag); + return rc; +} + + + +RTDECL(int) RTAsn1ObjId_DecodeAsn1(PRTASN1CURSOR pCursor, uint32_t fFlags, PRTASN1OBJID pThis, const char *pszErrorTag) +{ + int rc = RTAsn1CursorReadHdr(pCursor, &pThis->Asn1Core, pszErrorTag); + if (RT_SUCCESS(rc)) + { + rc = RTAsn1CursorMatchTagClassFlags(pCursor, &pThis->Asn1Core, ASN1_TAG_OID, + ASN1_TAGCLASS_UNIVERSAL | ASN1_TAGFLAG_PRIMITIVE, fFlags, pszErrorTag, "OID"); + if (RT_SUCCESS(rc)) + { + /* + * Validate and count things first. + */ + uint8_t cComponents = 0; /* gcc maybe-crap */ + uint8_t cchObjId = 0; /* ditto */ + rc = rtAsn1ObjId_PreParse(pCursor->pbCur, pThis->Asn1Core.cb, pCursor, pszErrorTag, &cComponents, &cchObjId); + if (RT_SUCCESS(rc)) + { + /* + * Allocate memory for the components array, either out of the + * string buffer or off the heap. + */ + pThis->cComponents = cComponents; + RTAsn1CursorInitAllocation(pCursor, &pThis->Allocation); +#if 0 /** @todo breaks with arrays of ObjIds or structs containing them. They get resized and repositioned in memory, thus invalidating the pointer. Add recall-pointers callback, or just waste memory? Or maybe make all arrays pointer-arrays? */ + if (cComponents * sizeof(uint32_t) <= sizeof(pThis->szObjId) - cchObjId - 1) + pThis->pauComponents = (uint32_t *)&pThis->szObjId[sizeof(pThis->szObjId) - cComponents * sizeof(uint32_t)]; + else +#endif + rc = RTAsn1MemAllocZ(&pThis->Allocation, (void **)&pThis->pauComponents, + cComponents * sizeof(pThis->pauComponents[0])); + if (RT_SUCCESS(rc)) + { + uint32_t *pauComponents = (uint32_t *)pThis->pauComponents; + + /* + * Deal with the two first components first since they are + * encoded in a weird way to save a byte. + */ + uint8_t const *pbContent = pCursor->pbCur; + uint32_t cbContent = pThis->Asn1Core.cb; + uint32_t uValue; + rc = rtAsn1ObjId_ReadComponent(pbContent, cbContent, &uValue); AssertRC(rc); + if (RT_SUCCESS(rc)) + { + pbContent += rc; + cbContent -= rc; + + if (uValue < 80) + { + pauComponents[0] = uValue / 40; + pauComponents[1] = uValue % 40; + } + else + { + pauComponents[0] = 2; + pauComponents[1] = uValue - 2*40; + } + + char *pszObjId = &pThis->szObjId[0]; + *pszObjId++ = g_achDigits[pauComponents[0]]; + size_t cbObjIdLeft = cchObjId + 1 - 1; + + rc = rtAsn1ObjId_InternalFormatComponent(pauComponents[1], &pszObjId, &cbObjIdLeft); AssertRC(rc); + if (RT_SUCCESS(rc)) + { + /* + * The other components are encoded in less complicated manner. + */ + for (uint32_t i = 2; i < cComponents; i++) + { + rc = rtAsn1ObjId_ReadComponent(pbContent, cbContent, &uValue); + AssertRCBreak(rc); + pbContent += rc; + cbContent -= rc; + pauComponents[i] = uValue; + rc = rtAsn1ObjId_InternalFormatComponent(uValue, &pszObjId, &cbObjIdLeft); + AssertRCBreak(rc); + } + if (RT_SUCCESS(rc)) + { + Assert(cbObjIdLeft == 1); + *pszObjId = '\0'; + + RTAsn1CursorSkip(pCursor, pThis->Asn1Core.cb); + pThis->Asn1Core.fFlags |= RTASN1CORE_F_PRIMITE_TAG_STRUCT; + pThis->Asn1Core.pOps = &g_RTAsn1ObjId_Vtable; + return VINF_SUCCESS; + } + } + } + RTAsn1MemFree(&pThis->Allocation, (void *)pThis->pauComponents); + pThis->pauComponents = NULL; + } + } + } + } + RT_ZERO(*pThis); + return rc; +} + + + +/* + * Generate code for the associated collection types. + */ +#define RTASN1TMPL_TEMPLATE_FILE "../common/asn1/asn1-ut-objid-template.h" +#include <iprt/asn1-generator-internal-header.h> +#include <iprt/asn1-generator-asn1-decoder.h> + |