/* $Id: VBoxEditCoffLib.cpp $ */ /** @file * VBoxEditCoffLib - Simple COFF editor for library files. */ /* * Copyright (C) 2006-2022 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 . * * SPDX-License-Identifier: GPL-3.0-only */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #include #include #include #include #include #include #include /********************************************************************************************************************************* * Structures and Typedefs * *********************************************************************************************************************************/ typedef struct ARHDR { char achName[16]; char achDate[12]; char achUid[6]; char achGid[6]; char achMode[8]; char achSize[10]; char achMagic[2]; } ARHDR; AssertCompileSize(ARHDR, 16+12+6+6+8+10+2); /********************************************************************************************************************************* * Global Variables * *********************************************************************************************************************************/ /** Verbosity level. */ static int g_cVerbosity = 0; /** The binary size. */ static unsigned g_cbBinary = 0; /** The binary data we're editing. */ static uint8_t *g_pbBinary = NULL; /** Size of the currently selected member. */ static unsigned g_cbMember = 0; /** Pointer to the data for the currently selected member. */ static uint8_t *g_pbMember = NULL; /** * File size. * * @returns file size in bytes. * @returns 0 on failure. * @param pFile File to size. */ static unsigned fsize(FILE *pFile) { long cbFile; off_t Pos = ftell(pFile); if ( Pos >= 0 && !fseek(pFile, 0, SEEK_END)) { cbFile = ftell(pFile); if ( cbFile >= 0 && !fseek(pFile, 0, SEEK_SET)) return cbFile; } return 0; } /** * Reports a problem. * * @returns RTEXITCODE_FAILURE */ static int error(const char *pszFormat, ...) { fprintf(stderr, "error: "); va_list va; va_start(va, pszFormat); vfprintf(stderr, pszFormat, va); va_end(va); return RTEXITCODE_FAILURE; } /** * Reports a syntax problem. * * @returns RTEXITCODE_SYNTAX */ static int syntax(const char *pszFormat, ...) { fprintf(stderr, "syntax error: "); va_list va; va_start(va, pszFormat); vfprintf(stderr, pszFormat, va); va_end(va); return RTEXITCODE_FAILURE; } /** * Display usage * * @returns success if stdout, syntax error if stderr. */ static int usage(FILE *pOut, const char *argv0) { fprintf(pOut, "usage: %s --input --output [options and operations]\n" "\n" "Operations and Options (processed in place):\n" " --verbose Noisier.\n" " --quiet Quiet execution.\n" " --select \n" " Selects archive member which name ends in the given string.\n" " --redefine-sym =\n" " Redefine the symbol to .\n" " Note! the length must be the same!\n" , argv0); return pOut == stdout ? RTEXITCODE_SUCCESS : RTEXITCODE_SYNTAX; } /** * Helper for SelectMember. */ static bool AreAllDigits(const char *pch, size_t cch, size_t *puValue) { *puValue = 0; do { if (!RT_C_IS_DIGIT(*pch)) return false; *puValue = *puValue * 10 + *pch - '0'; pch++; cch--; } while (cch > 0); return true; } /** * Selects archive member ending with the given name. * * Updates g_cbMember and g_pbMember. */ static int SelectMember(const char *pszEndsWith) { size_t const cchEndsWith = strlen(pszEndsWith); /* * Check the header. */ if (memcmp(g_pbBinary, RT_STR_TUPLE("!\n"))) return error("Not an AR library!\n"); /* * Work the members. */ const char *pszStringTab = NULL; size_t cbStringTab = 0; for (size_t off = sizeof("!\n") - 1; off < g_cbBinary;) { ARHDR *pHdr = (ARHDR *)&g_pbBinary[off]; char szTmp[16 + 8]; size_t uValue; char *pszIgn; #define COPY_AND_TRIM(a_pchSrc, a_cbSrc) do { \ memcpy(szTmp, (a_pchSrc), (a_cbSrc)); \ size_t offCopy = (a_cbSrc); \ while (offCopy > 0 && (szTmp[offCopy - 1] == ' ' || szTmp[offCopy - 1] == '\0')) \ offCopy--; \ szTmp[offCopy] = '\0'; \ } while (0) /* * Parse the header. */ /* The size: */ COPY_AND_TRIM(pHdr->achSize, sizeof(pHdr->achSize)); size_t cbFile = strtol(szTmp, &pszIgn, 10); /* The name: */ size_t cbExtra = 0; size_t cchName = sizeof(pHdr->achName); const char *pchName = pHdr->achName; if ( pchName[0] == '#' && pchName[1] == '1' && pchName[2] == '/') { COPY_AND_TRIM(&pchName[3], cchName - 3); cchName = cbExtra = strtol(szTmp, &pszIgn, 10); pchName = (char *)(pHdr + 1); } else { while (cchName > 0 && (pchName[cchName - 1] == ' ' || pchName[cchName - 1] == '\0')) cchName--; /* Long filename string table? */ if ( (cchName == 2 && pchName[0] == '/' && pchName[1] == '/') || (cchName == sizeof("ARFILENAMES/") - 1 && memcmp(pchName, RT_STR_TUPLE("ARFILENAMES/")) == 0)) { pszStringTab = (char *)(pHdr + 1); cbStringTab = cbFile; } /* Long filename string table reference? */ else if ( cchName >= 2 && ( pchName[0] == '/' /* System V */ || pchName[0] == ' ' /* Other */) && AreAllDigits(&pchName[1], cchName - 1, &uValue) && uValue < cbStringTab) { pchName = &pszStringTab[uValue]; cchName = strlen(pchName); /** @todo unsafe! */ } /* Drop trailing slash in case of System V filename: */ else if (cchName > 1 && pchName[cchName - 1] == '/') cchName -= 1; } if (g_cVerbosity > 2) fprintf(stderr, "debug: %#08x: %#010x %*.*s\n", (unsigned)off, (unsigned)(cbFile - cbExtra), (int)cchName, (int)cchName, pchName); /* * Do matching. */ if ( cchName >= cchEndsWith && strncmp(&pchName[cchName - cchEndsWith], pszEndsWith, cchEndsWith) == 0) { g_pbMember = (uint8_t *)(pHdr + 1) + cbExtra; g_cbMember = (unsigned)(cbFile - cbExtra); if (g_cVerbosity > 1) fprintf(stderr, "debug: selected '%*.*s': %#x LB %#x\n", (int)cchName, (int)cchName, pchName, (unsigned)(off + sizeof(*pHdr) + cbExtra), g_cbMember); return 0; } /* * Advance. */ off += sizeof(ARHDR) + cbFile + (cbFile & 1); } return error("No member ending with '%s' was found!\n", pszEndsWith); } /** * @note Borrowed from VBoxBs3objConverter.cpp */ static const char *coffGetSymbolName(PCIMAGE_SYMBOL pSym, const char *pchStrTab, uint32_t cbStrTab, char pszShortName[16]) { if (pSym->N.Name.Short != 0) { memcpy(pszShortName, pSym->N.ShortName, 8); pszShortName[8] = '\0'; return pszShortName; } if (pSym->N.Name.Long < cbStrTab) { uint32_t const cbLeft = cbStrTab - pSym->N.Name.Long; const char *pszRet = pchStrTab + pSym->N.Name.Long; if (memchr(pszRet, '\0', cbLeft) != NULL) return pszRet; } error("Invalid string table index %#x!\n", pSym->N.Name.Long); return "Invalid Symbol Table Entry"; } /** * Redefine a symbol with a different name. */ static int RedefineSymbol(const char *pszOldEqualNew) { /* * Check state and split up the input. */ if (!g_pbMember) return error("No selected archive member!\n"); const char *pszNew = strchr(pszOldEqualNew, '='); if (!pszNew || pszNew[1] == '\0') return error("Malformed 'old=new' argument: %s\n", pszOldEqualNew); const char *pszOld = pszOldEqualNew; size_t const cchOld = pszNew - pszOldEqualNew; pszNew += 1; size_t const cchNew = strlen(pszNew); if (cchNew > cchOld) return error("The new symbol must not be longer than the old symbol: %#x vs %#x (%s)\n", cchNew, cchOld, pszOldEqualNew); if (g_cVerbosity > 2) fprintf(stderr, "debug: redefining symbol '%*.*s' to '%*.*s'...\n", (int)cchOld, (int)cchOld, pszOld, (int)cchNew, (int)cchNew, pszNew); /* * Parse COFF header. */ const IMAGE_FILE_HEADER *pHdr = (const IMAGE_FILE_HEADER *)g_pbMember; if (sizeof(*pHdr) >= g_cbMember) return error("member too small for COFF\n"); if ( pHdr->Machine != IMAGE_FILE_MACHINE_AMD64 && pHdr->Machine != IMAGE_FILE_MACHINE_I386) return error("Unsupported COFF machine: %#x\n", pHdr->Machine); if ( pHdr->PointerToSymbolTable >= g_cbMember || pHdr->PointerToSymbolTable < sizeof(*pHdr)) return error("PointerToSymbolTable is out of bounds: %#x, max %#x\n", pHdr->PointerToSymbolTable, g_cbMember); unsigned const cSymbols = pHdr->NumberOfSymbols; if ( cSymbols >= g_cbMember - pHdr->PointerToSymbolTable || cSymbols * sizeof(IMAGE_SYMBOL) > g_cbMember - pHdr->PointerToSymbolTable) return error("PointerToSymbolTable + NumberOfSymbols is out of bounds: %#x + %#x * %#x (%#x), max %#x\n", pHdr->PointerToSymbolTable, cSymbols, sizeof(IMAGE_SYMBOL), pHdr->PointerToSymbolTable + cSymbols * sizeof(IMAGE_SYMBOL), g_cbMember); /* * Work the symbol table. */ unsigned cRenames = 0; PIMAGE_SYMBOL const paSymTab = (PIMAGE_SYMBOL)&g_pbMember[pHdr->PointerToSymbolTable]; const char * const pchStrTab = (const char *)&paSymTab[pHdr->NumberOfSymbols]; uint32_t const cbStrTab = (uint32_t)((uintptr_t)&g_pbMember[g_cbMember] - (uintptr_t)pchStrTab); for (unsigned iSym = 0; iSym < cSymbols; iSym++) { char szShort[16]; const char *pszSymName = coffGetSymbolName(&paSymTab[iSym], pchStrTab, cbStrTab, szShort); size_t cchSymName = strlen(pszSymName); if (g_cVerbosity > 3 && cchSymName > 0) fprintf(stderr, "debug: symbol %u: %s\n", iSym, pszSymName); if ( cchSymName == cchOld && memcmp(pszSymName, pszOld, cchSymName) == 0) { size_t const offStrTab = (size_t)(pszSymName - pchStrTab); if (offStrTab < cbStrTab) { if (g_cVerbosity > 1) fprintf(stderr, "debug: Found symbol '%s' in at string table offset %#x, renaming to '%s'.\n", pszSymName, (uint32_t)offStrTab, pszNew); if (offStrTab > 0 && pchStrTab[offStrTab - 1] != '\0') return error("Cannot rename sub-string!\n"); memset((char *)pszSymName, 0, cchOld); memcpy((char *)pszSymName, pszNew, cchNew); } else { if (g_cVerbosity > 1) fprintf(stderr, "debug: Found symbol '%s' in symbol table, renaming to '%s'.\n", pszSymName, pszNew); memset(paSymTab[iSym].N.ShortName, 0, sizeof(paSymTab[iSym].N.ShortName)); memcpy(paSymTab[iSym].N.ShortName, pszNew, cchNew); } cRenames++; } /* Skip AUX symbols. */ uint8_t cAuxSyms = paSymTab[iSym].NumberOfAuxSymbols; while (cAuxSyms-- > 0) iSym++; } if (cRenames > 0) return RTEXITCODE_SUCCESS; return error("Symbol '%*.*s' was not found!\n", cchOld, cchOld, pszOld); } int main(int argc, char **argv) { /* * Parse arguments. */ const char *pszIn = NULL; const char *pszOut = NULL; for (int i = 1; i < argc; i++) { const char *pszArg = argv[i]; /* Options without values first: */ if ( strcmp(pszArg, "--verbose") == 0 || strcmp(pszArg, "-v") == 0) g_cVerbosity += 1; else if ( strcmp(pszArg, "--quiet") == 0 || strcmp(pszArg, "--q") == 0) g_cVerbosity = 0; else if ( strcmp(pszArg, "--help") == 0 || strcmp(pszArg, "-h") == 0 || strcmp(pszArg, "-?") == 0) return usage(stdout, argv[0]); else if (i + 1 >= argc) return syntax("Missing argument value or unknown option '%s'!\n", pszArg); else { i++; const char *pszValue = argv[i]; int rc = 0; if (strcmp(pszArg, "--input") == 0) { if (pszIn) return syntax("--input can only be specified once!\n"); pszIn = pszValue; /* Load it into memory: */ FILE *pIn = fopen(pszIn, "rb"); if (!pIn) return error("Failed to open '%s' for reading!\n", pszIn); g_cbBinary = fsize(pIn); if (!g_cbBinary) return error("Failed to determin the size of '%s'!\n", pszIn); if (g_cbBinary > _128M) return error("'%s' is too large: %x, max %x\n", g_cbBinary, (size_t)_128M); g_pbBinary = (uint8_t *)calloc(1, g_cbBinary + 4096); if (!g_pbBinary) return error("Out of memory!\n"); if (fread(g_pbBinary, g_cbBinary, 1, pIn) != 1) return error("Failed to read '%s' into memory!\n", pszIn); fclose(pIn); } else if (strcmp(pszArg, "--output") == 0) pszOut = pszValue; else if (strcmp(pszArg, "--select") == 0) rc = SelectMember(pszValue); else if (strcmp(pszArg, "--redefine-sym") == 0) rc = RedefineSymbol(pszValue); else return syntax("Unknown option: %s\n", pszArg); if (rc != RTEXITCODE_SUCCESS) return rc; } } if (!pszIn || !pszOut) return syntax("No %s specified!\n", pszIn ? "output file" : "intput library file"); /* * Write out the result. */ FILE *pOut = fopen(pszOut, "wb"); if (!pOut) return error("Failed to open '%s' for writing!\n", pszOut); if (fwrite(g_pbBinary, g_cbBinary, 1, pOut) != 1) return error("Error writing %#x bytes to '%s'!\n", g_cbBinary, pszOut); if (fclose(pOut) != 0) return error("Error closing '%s'!\n", pszOut); return RTEXITCODE_SUCCESS; }