| /* |
| * Copyright (C) 2004 - 2006 Tomasz Kojm <tkojm@clamav.net> |
| * aCaB <acab@clamav.net> |
| * |
| * 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; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, |
| * MA 02110-1301, USA. |
| */ |
| |
| #if HAVE_CONFIG_H |
| #include "clamav-config.h" |
| #endif |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <sys/stat.h> |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| #include <time.h> |
| #include <stdarg.h> |
| |
| #include "cltypes.h" |
| #include "clamav.h" |
| #include "others.h" |
| #include "pe.h" |
| #include "petite.h" |
| #include "fsg.h" |
| #include "spin.h" |
| #include "upx.h" |
| #include "yc.h" |
| #include "aspack.h" |
| #include "wwunpack.h" |
| #include "unsp.h" |
| #include "scanners.h" |
| #include "str.h" |
| #include "execs.h" |
| #include "md5.h" |
| #include "mew.h" |
| #include "upack.h" |
| #include "matcher.h" |
| #include "matcher-bm.h" |
| |
| #ifndef O_BINARY |
| #define O_BINARY 0 |
| #endif |
| |
| #define DCONF ctx->dconf->pe |
| |
| #define IMAGE_DOS_SIGNATURE 0x5a4d /* MZ */ |
| #define IMAGE_DOS_SIGNATURE_OLD 0x4d5a /* ZM */ |
| #define IMAGE_NT_SIGNATURE 0x00004550 |
| #define PE32_SIGNATURE 0x010b |
| #define PE32P_SIGNATURE 0x020b |
| |
| #define optional_hdr64 pe_opt.opt64 |
| #define optional_hdr32 pe_opt.opt32 |
| |
| #define UPX_NRV2B "\x11\xdb\x11\xc9\x01\xdb\x75\x07\x8b\x1e\x83\xee\xfc\x11\xdb\x11\xc9\x11\xc9\x75\x20\x41\x01\xdb" |
| #define UPX_NRV2D "\x83\xf0\xff\x74\x78\xd1\xf8\x89\xc5\xeb\x0b\x01\xdb\x75\x07\x8b\x1e\x83\xee\xfc\x11\xdb\x11\xc9" |
| #define UPX_NRV2E "\xeb\x52\x31\xc9\x83\xe8\x03\x72\x11\xc1\xe0\x08\x8a\x06\x46\x83\xf0\xff\x74\x75\xd1\xf8\x89\xc5" |
| |
| #define EC32(x) le32_to_host(x) /* Convert little endian to host */ |
| #define EC16(x) le16_to_host(x) |
| /* lower and upper bondary alignment (size vs offset) */ |
| #define PEALIGN(o,a) (((a))?(((o)/(a))*(a)):(o)) |
| #define PESALIGN(o,a) (((a))?(((o)/(a)+((o)%(a)!=0))*(a)):(o)) |
| |
| #define CLI_UNPSIZELIMITS(NAME,CHK) \ |
| if(ctx->limits && ctx->limits->maxfilesize && (CHK) > ctx->limits->maxfilesize) { \ |
| cli_dbgmsg(NAME": Sizes exceeded (%lu > %lu)\n", (CHK), ctx->limits->maxfilesize); \ |
| free(exe_sections); \ |
| if(BLOCKMAX) { \ |
| *ctx->virname = "PE."NAME".ExceededFileSize"; \ |
| return CL_VIRUS; \ |
| } else { \ |
| return CL_CLEAN; \ |
| } \ |
| } |
| |
| #define CLI_UNPTEMP(NAME,FREEME) \ |
| if(!(tempfile = cli_gentemp(NULL))) { \ |
| cli_multifree FREEME; \ |
| return CL_EMEM; \ |
| } \ |
| if((ndesc = open(tempfile, O_RDWR|O_CREAT|O_TRUNC|O_BINARY, S_IRWXU)) < 0) { \ |
| cli_dbgmsg(NAME": Can't create file %s\n", tempfile); \ |
| free(tempfile); \ |
| cli_multifree FREEME; \ |
| return CL_EIO; \ |
| } |
| |
| #define CLI_TMPUNLK() if(!cli_leavetemps_flag) unlink(tempfile) |
| |
| #define FSGCASE(NAME,FREESEC) \ |
| case 0: /* Unpacked and NOT rebuilt */ \ |
| cli_dbgmsg(NAME": Successfully decompressed\n"); \ |
| close(ndesc); \ |
| unlink(tempfile); \ |
| free(tempfile); \ |
| FREESEC; \ |
| found = 0; \ |
| upx_success = 1; \ |
| break; /* FSG ONLY! - scan raw data after upx block */ |
| |
| #define SPINCASE() \ |
| case 2: \ |
| free(spinned); \ |
| close(ndesc); \ |
| unlink(tempfile); \ |
| cli_dbgmsg("PESpin: Size exceeded\n"); \ |
| if(BLOCKMAX) { \ |
| free(tempfile); \ |
| free(exe_sections); \ |
| *ctx->virname = "PE.Pespin.ExceededFileSize"; \ |
| return CL_VIRUS; \ |
| } \ |
| free(tempfile); \ |
| break; \ |
| |
| #define CLI_UNPRESULTS_(NAME,FSGSTUFF,EXPR,GOOD,FREEME) \ |
| switch(EXPR) { \ |
| case GOOD: /* Unpacked and rebuilt */ \ |
| if(cli_leavetemps_flag) \ |
| cli_dbgmsg(NAME": Unpacked and rebuilt executable saved in %s\n", tempfile); \ |
| else \ |
| cli_dbgmsg(NAME": Unpacked and rebuilt executable\n"); \ |
| cli_multifree FREEME; \ |
| free(exe_sections); \ |
| fsync(ndesc); \ |
| lseek(ndesc, 0, SEEK_SET); \ |
| cli_dbgmsg("***** Scanning rebuilt PE file *****\n"); \ |
| if(cli_magic_scandesc(ndesc, ctx) == CL_VIRUS) { \ |
| close(ndesc); \ |
| CLI_TMPUNLK(); \ |
| free(tempfile); \ |
| return CL_VIRUS; \ |
| } \ |
| close(ndesc); \ |
| CLI_TMPUNLK(); \ |
| free(tempfile); \ |
| return CL_CLEAN; \ |
| \ |
| FSGSTUFF; \ |
| \ |
| default: \ |
| cli_dbgmsg(NAME": Unpacking failed\n"); \ |
| close(ndesc); \ |
| unlink(tempfile); \ |
| cli_multifree FREEME; \ |
| free(tempfile); \ |
| } |
| |
| |
| #define CLI_UNPRESULTS(NAME,EXPR,GOOD,FREEME) CLI_UNPRESULTS_(NAME,NULL,EXPR,GOOD,FREEME) |
| #define CLI_UNPRESULTSFSG1(NAME,EXPR,GOOD,FREEME) CLI_UNPRESULTS_(NAME,FSGCASE(NAME,free(sections)),EXPR,GOOD,FREEME) |
| #define CLI_UNPRESULTSFSG2(NAME,EXPR,GOOD,FREEME) CLI_UNPRESULTS_(NAME,FSGCASE(NAME,NULL),EXPR,GOOD,FREEME) |
| |
| struct offset_list { |
| uint32_t offset; |
| struct offset_list *next; |
| }; |
| |
| static void cli_multifree(void *f, ...) { |
| void *ff; |
| va_list ap; |
| free(f); |
| va_start(ap, f); |
| while((ff=va_arg(ap, void*))) free(ff); |
| va_end(ap); |
| } |
| |
| static uint32_t cli_rawaddr(uint32_t rva, struct cli_exe_section *shp, uint16_t nos, unsigned int *err, size_t fsize, uint32_t hdr_size) |
| { |
| int i, found = 0; |
| uint32_t ret; |
| |
| if (rva<hdr_size) { /* Out of section EP - mapped to imagebase+rva */ |
| if (rva >= fsize) { |
| *err=1; |
| return 0; |
| } |
| *err=0; |
| return rva; |
| } |
| |
| for(i = nos-1; i >= 0; i--) { |
| if(shp[i].rsz && shp[i].rva <= rva && shp[i].rsz > rva - shp[i].rva) { |
| found = 1; |
| break; |
| } |
| } |
| |
| if(!found) { |
| *err = 1; |
| return 0; |
| } |
| |
| ret = rva - shp[i].rva + shp[i].raw; |
| *err = 0; |
| return ret; |
| } |
| |
| |
| /* |
| static int cli_ddump(int desc, int offset, int size, const char *file) { |
| int pos, ndesc, bread, sum = 0; |
| char buff[FILEBUFF]; |
| |
| |
| cli_dbgmsg("in ddump()\n"); |
| |
| if((pos = lseek(desc, 0, SEEK_CUR)) == -1) { |
| cli_dbgmsg("Invalid descriptor\n"); |
| return -1; |
| } |
| |
| if(lseek(desc, offset, SEEK_SET) == -1) { |
| cli_dbgmsg("lseek() failed\n"); |
| lseek(desc, pos, SEEK_SET); |
| return -1; |
| } |
| |
| if((ndesc = open(file, O_WRONLY|O_CREAT|O_TRUNC|O_BINARY, S_IRWXU)) < 0) { |
| cli_dbgmsg("Can't create file %s\n", file); |
| lseek(desc, pos, SEEK_SET); |
| return -1; |
| } |
| |
| while((bread = cli_readn(desc, buff, FILEBUFF)) > 0) { |
| if(sum + bread >= size) { |
| if(write(ndesc, buff, size - sum) == -1) { |
| cli_dbgmsg("Can't write to file\n"); |
| lseek(desc, pos, SEEK_SET); |
| close(ndesc); |
| unlink(file); |
| return -1; |
| } |
| break; |
| } else { |
| if(write(ndesc, buff, bread) == -1) { |
| cli_dbgmsg("Can't write to file\n"); |
| lseek(desc, pos, SEEK_SET); |
| close(ndesc); |
| unlink(file); |
| return -1; |
| } |
| } |
| sum += bread; |
| } |
| |
| close(ndesc); |
| lseek(desc, pos, SEEK_SET); |
| return 0; |
| } |
| */ |
| |
| static off_t cli_seeksect(int fd, struct cli_exe_section *s) { |
| off_t ret; |
| |
| if(!s->rsz) return 0; |
| if((ret=lseek(fd, s->raw, SEEK_SET)) == -1) |
| cli_dbgmsg("cli_seeksect: lseek() failed\n"); |
| return ret+1; |
| } |
| |
| static unsigned int cli_md5sect(int fd, struct cli_exe_section *s, unsigned char *digest) { |
| void *hashme; |
| cli_md5_ctx md5; |
| |
| if (s->rsz > CLI_MAX_ALLOCATION) { |
| cli_dbgmsg("cli_md5sect: skipping md5 calculation for too big section\n"); |
| return 0; |
| } |
| |
| if(!cli_seeksect(fd, s)) return 0; |
| |
| if(!(hashme=cli_malloc(s->rsz))) { |
| cli_dbgmsg("cli_md5sect: out of memory\n"); |
| return 0; |
| } |
| |
| if(cli_readn(fd, hashme, s->rsz)!=s->rsz) { |
| cli_dbgmsg("cli_md5sect: unable to read section data\n"); |
| return 0; |
| } |
| |
| cli_md5_init(&md5); |
| cli_md5_update(&md5, hashme, s->rsz); |
| free(hashme); |
| cli_md5_final(digest, &md5); |
| return 1; |
| } |
| |
| int cli_scanpe(int desc, cli_ctx *ctx) |
| { |
| uint16_t e_magic; /* DOS signature ("MZ") */ |
| uint16_t nsections; |
| uint32_t e_lfanew; /* address of new exe header */ |
| uint32_t ep, vep; /* entry point (raw, virtual) */ |
| uint8_t polipos = 0; |
| time_t timestamp; |
| struct pe_image_file_hdr file_hdr; |
| union { |
| struct pe_image_optional_hdr64 opt64; |
| struct pe_image_optional_hdr32 opt32; |
| } pe_opt; |
| struct pe_image_section_hdr *section_hdr; |
| struct stat sb; |
| char sname[9], buff[4096], epbuff[4096], *tempfile; |
| uint32_t epsize; |
| ssize_t bytes; |
| unsigned int i, found, upx_success = 0, min = 0, max = 0, err; |
| unsigned int ssize = 0, dsize = 0, dll = 0, pe_plus = 0; |
| int (*upxfn)(char *, uint32_t, char *, uint32_t *, uint32_t, uint32_t, uint32_t) = NULL; |
| char *src = NULL, *dest = NULL; |
| int ndesc, ret = CL_CLEAN, upack = 0, native=0; |
| size_t fsize; |
| uint32_t valign, falign, hdr_size, j; |
| struct cli_exe_section *exe_sections; |
| struct cli_matcher *md5_sect; |
| |
| |
| if(!ctx) { |
| cli_errmsg("cli_scanpe: ctx == NULL\n"); |
| return CL_ENULLARG; |
| } |
| |
| if(cli_readn(desc, &e_magic, sizeof(e_magic)) != sizeof(e_magic)) { |
| cli_dbgmsg("Can't read DOS signature\n"); |
| return CL_CLEAN; |
| } |
| |
| if(EC16(e_magic) != IMAGE_DOS_SIGNATURE && EC16(e_magic) != IMAGE_DOS_SIGNATURE_OLD) { |
| cli_dbgmsg("Invalid DOS signature\n"); |
| return CL_CLEAN; |
| } |
| |
| lseek(desc, 58, SEEK_CUR); /* skip to the end of the DOS header */ |
| |
| if(cli_readn(desc, &e_lfanew, sizeof(e_lfanew)) != sizeof(e_lfanew)) { |
| cli_dbgmsg("Can't read new header address\n"); |
| /* truncated header? */ |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| e_lfanew = EC32(e_lfanew); |
| cli_dbgmsg("e_lfanew == %d\n", e_lfanew); |
| if(!e_lfanew) { |
| cli_dbgmsg("Not a PE file\n"); |
| return CL_CLEAN; |
| } |
| |
| if(lseek(desc, e_lfanew, SEEK_SET) < 0) { |
| /* probably not a PE file */ |
| cli_dbgmsg("Can't lseek to e_lfanew\n"); |
| return CL_CLEAN; |
| } |
| |
| if(cli_readn(desc, &file_hdr, sizeof(struct pe_image_file_hdr)) != sizeof(struct pe_image_file_hdr)) { |
| /* bad information in e_lfanew - probably not a PE file */ |
| cli_dbgmsg("Can't read file header\n"); |
| return CL_CLEAN; |
| } |
| |
| if(EC32(file_hdr.Magic) != IMAGE_NT_SIGNATURE) { |
| cli_dbgmsg("Invalid PE signature (probably NE file)\n"); |
| return CL_CLEAN; |
| } |
| |
| if(EC16(file_hdr.Characteristics) & 0x2000) { |
| cli_dbgmsg("File type: DLL\n"); |
| dll = 1; |
| } else if(EC16(file_hdr.Characteristics) & 0x01) { |
| cli_dbgmsg("File type: Executable\n"); |
| } |
| |
| switch(EC16(file_hdr.Machine)) { |
| case 0x0: |
| cli_dbgmsg("Machine type: Unknown\n"); |
| break; |
| case 0x14c: |
| cli_dbgmsg("Machine type: 80386\n"); |
| break; |
| case 0x14d: |
| cli_dbgmsg("Machine type: 80486\n"); |
| break; |
| case 0x14e: |
| cli_dbgmsg("Machine type: 80586\n"); |
| break; |
| case 0x160: |
| cli_dbgmsg("Machine type: R30000 (big-endian)\n"); |
| break; |
| case 0x162: |
| cli_dbgmsg("Machine type: R3000\n"); |
| break; |
| case 0x166: |
| cli_dbgmsg("Machine type: R4000\n"); |
| break; |
| case 0x168: |
| cli_dbgmsg("Machine type: R10000\n"); |
| break; |
| case 0x184: |
| cli_dbgmsg("Machine type: DEC Alpha AXP\n"); |
| break; |
| case 0x284: |
| cli_dbgmsg("Machine type: DEC Alpha AXP 64bit\n"); |
| break; |
| case 0x1f0: |
| cli_dbgmsg("Machine type: PowerPC\n"); |
| break; |
| case 0x200: |
| cli_dbgmsg("Machine type: IA64\n"); |
| break; |
| case 0x268: |
| cli_dbgmsg("Machine type: M68k\n"); |
| break; |
| case 0x266: |
| cli_dbgmsg("Machine type: MIPS16\n"); |
| break; |
| case 0x366: |
| cli_dbgmsg("Machine type: MIPS+FPU\n"); |
| break; |
| case 0x466: |
| cli_dbgmsg("Machine type: MIPS16+FPU\n"); |
| break; |
| case 0x1a2: |
| cli_dbgmsg("Machine type: Hitachi SH3\n"); |
| break; |
| case 0x1a3: |
| cli_dbgmsg("Machine type: Hitachi SH3-DSP\n"); |
| break; |
| case 0x1a4: |
| cli_dbgmsg("Machine type: Hitachi SH3-E\n"); |
| break; |
| case 0x1a6: |
| cli_dbgmsg("Machine type: Hitachi SH4\n"); |
| break; |
| case 0x1a8: |
| cli_dbgmsg("Machine type: Hitachi SH5\n"); |
| break; |
| case 0x1c0: |
| cli_dbgmsg("Machine type: ARM\n"); |
| break; |
| case 0x1c2: |
| cli_dbgmsg("Machine type: THUMB\n"); |
| break; |
| case 0x1d3: |
| cli_dbgmsg("Machine type: AM33\n"); |
| break; |
| case 0x520: |
| cli_dbgmsg("Machine type: Infineon TriCore\n"); |
| break; |
| case 0xcef: |
| cli_dbgmsg("Machine type: CEF\n"); |
| break; |
| case 0xebc: |
| cli_dbgmsg("Machine type: EFI Byte Code\n"); |
| break; |
| case 0x9041: |
| cli_dbgmsg("Machine type: M32R\n"); |
| break; |
| case 0xc0ee: |
| cli_dbgmsg("Machine type: CEE\n"); |
| break; |
| case 0x8664: |
| cli_dbgmsg("Machine type: AMD64\n"); |
| break; |
| default: |
| cli_warnmsg("Unknown machine type in PE header (0x%x)\n", EC16(file_hdr.Machine)); |
| } |
| |
| nsections = EC16(file_hdr.NumberOfSections); |
| if(nsections < 1 || nsections > 96) { |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| if(nsections) |
| cli_warnmsg("PE file contains %d sections\n", nsections); |
| else |
| cli_warnmsg("PE file contains no sections\n"); |
| return CL_CLEAN; |
| } |
| cli_dbgmsg("NumberOfSections: %d\n", nsections); |
| |
| timestamp = (time_t) EC32(file_hdr.TimeDateStamp); |
| cli_dbgmsg("TimeDateStamp: %s", ctime(×tamp)); |
| |
| cli_dbgmsg("SizeOfOptionalHeader: %x\n", EC16(file_hdr.SizeOfOptionalHeader)); |
| |
| if (EC16(file_hdr.SizeOfOptionalHeader) < sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("SizeOfOptionalHeader too small\n"); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| if(cli_readn(desc, &optional_hdr32, sizeof(struct pe_image_optional_hdr32)) != sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("Can't read optional file header\n"); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| /* This will be a chicken and egg problem until we drop 9x */ |
| if(EC32(optional_hdr64.Magic)==PE32P_SIGNATURE) { |
| if(EC16(file_hdr.SizeOfOptionalHeader)!=sizeof(struct pe_image_optional_hdr64)) { |
| /* FIXME: need to play around a bit more with xp64 */ |
| cli_dbgmsg("Incorrect SizeOfOptionalHeader for PE32+\n"); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| pe_plus = 1; |
| } else { |
| /* |
| either it's got a PE32_SIGNATURE or |
| we enable win9x compatibility in that we don't honor magic (see bb#119) |
| either way it's a 32bit thingy |
| */ |
| if(EC16(optional_hdr32.Magic) != PE32_SIGNATURE) { |
| cli_warnmsg("Incorrect magic number in optional header\n"); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| cli_dbgmsg("9x compatibility mode\n"); |
| } |
| } |
| |
| if(!pe_plus) { /* PE */ |
| if (EC16(file_hdr.SizeOfOptionalHeader)!=sizeof(struct pe_image_optional_hdr32)) { |
| /* Seek to the end of the long header */ |
| lseek(desc, (EC16(file_hdr.SizeOfOptionalHeader)-sizeof(struct pe_image_optional_hdr32)), SEEK_CUR); |
| } |
| |
| if(DCONF & PE_CONF_UPACK) |
| upack = (EC16(file_hdr.SizeOfOptionalHeader)==0x148); |
| |
| vep = EC32(optional_hdr32.AddressOfEntryPoint); |
| hdr_size = EC32(optional_hdr32.SizeOfHeaders); |
| cli_dbgmsg("File format: PE\n"); |
| |
| cli_dbgmsg("MajorLinkerVersion: %d\n", optional_hdr32.MajorLinkerVersion); |
| cli_dbgmsg("MinorLinkerVersion: %d\n", optional_hdr32.MinorLinkerVersion); |
| cli_dbgmsg("SizeOfCode: 0x%x\n", EC32(optional_hdr32.SizeOfCode)); |
| cli_dbgmsg("SizeOfInitializedData: 0x%x\n", EC32(optional_hdr32.SizeOfInitializedData)); |
| cli_dbgmsg("SizeOfUninitializedData: 0x%x\n", EC32(optional_hdr32.SizeOfUninitializedData)); |
| cli_dbgmsg("AddressOfEntryPoint: 0x%x\n", vep); |
| cli_dbgmsg("BaseOfCode: 0x%x\n", EC32(optional_hdr32.BaseOfCode)); |
| cli_dbgmsg("SectionAlignment: 0x%x\n", EC32(optional_hdr32.SectionAlignment)); |
| cli_dbgmsg("FileAlignment: 0x%x\n", EC32(optional_hdr32.FileAlignment)); |
| cli_dbgmsg("MajorSubsystemVersion: %d\n", EC16(optional_hdr32.MajorSubsystemVersion)); |
| cli_dbgmsg("MinorSubsystemVersion: %d\n", EC16(optional_hdr32.MinorSubsystemVersion)); |
| cli_dbgmsg("SizeOfImage: 0x%x\n", EC32(optional_hdr32.SizeOfImage)); |
| cli_dbgmsg("SizeOfHeaders: 0x%x\n", hdr_size); |
| cli_dbgmsg("NumberOfRvaAndSizes: %d\n", EC32(optional_hdr32.NumberOfRvaAndSizes)); |
| |
| } else { /* PE+ */ |
| /* read the remaining part of the header */ |
| if(cli_readn(desc, &optional_hdr32 + 1, sizeof(struct pe_image_optional_hdr64) - sizeof(struct pe_image_optional_hdr32)) != sizeof(struct pe_image_optional_hdr64) - sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("Can't read optional file header\n"); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| vep = EC32(optional_hdr64.AddressOfEntryPoint); |
| hdr_size = EC32(optional_hdr64.SizeOfHeaders); |
| cli_dbgmsg("File format: PE32+\n"); |
| |
| cli_dbgmsg("MajorLinkerVersion: %d\n", optional_hdr64.MajorLinkerVersion); |
| cli_dbgmsg("MinorLinkerVersion: %d\n", optional_hdr64.MinorLinkerVersion); |
| cli_dbgmsg("SizeOfCode: 0x%x\n", EC32(optional_hdr64.SizeOfCode)); |
| cli_dbgmsg("SizeOfInitializedData: 0x%x\n", EC32(optional_hdr64.SizeOfInitializedData)); |
| cli_dbgmsg("SizeOfUninitializedData: 0x%x\n", EC32(optional_hdr64.SizeOfUninitializedData)); |
| cli_dbgmsg("AddressOfEntryPoint: 0x%x\n", vep); |
| cli_dbgmsg("BaseOfCode: 0x%x\n", EC32(optional_hdr64.BaseOfCode)); |
| cli_dbgmsg("SectionAlignment: 0x%x\n", EC32(optional_hdr64.SectionAlignment)); |
| cli_dbgmsg("FileAlignment: 0x%x\n", EC32(optional_hdr64.FileAlignment)); |
| cli_dbgmsg("MajorSubsystemVersion: %d\n", EC16(optional_hdr64.MajorSubsystemVersion)); |
| cli_dbgmsg("MinorSubsystemVersion: %d\n", EC16(optional_hdr64.MinorSubsystemVersion)); |
| cli_dbgmsg("SizeOfImage: 0x%x\n", EC32(optional_hdr64.SizeOfImage)); |
| cli_dbgmsg("SizeOfHeaders: 0x%x\n", hdr_size); |
| cli_dbgmsg("NumberOfRvaAndSizes: %d\n", EC32(optional_hdr64.NumberOfRvaAndSizes)); |
| } |
| |
| |
| switch(pe_plus ? EC16(optional_hdr64.Subsystem) : EC16(optional_hdr32.Subsystem)) { |
| case 0: |
| cli_dbgmsg("Subsystem: Unknown\n"); |
| break; |
| case 1: |
| cli_dbgmsg("Subsystem: Native (svc)\n"); |
| native = 1; |
| break; |
| case 2: |
| cli_dbgmsg("Subsystem: Win32 GUI\n"); |
| break; |
| case 3: |
| cli_dbgmsg("Subsystem: Win32 console\n"); |
| break; |
| case 5: |
| cli_dbgmsg("Subsystem: OS/2 console\n"); |
| break; |
| case 7: |
| cli_dbgmsg("Subsystem: POSIX console\n"); |
| break; |
| case 8: |
| cli_dbgmsg("Subsystem: Native Win9x driver\n"); |
| break; |
| case 9: |
| cli_dbgmsg("Subsystem: WinCE GUI\n"); |
| break; |
| case 10: |
| cli_dbgmsg("Subsystem: EFI application\n"); |
| break; |
| case 11: |
| cli_dbgmsg("Subsystem: EFI driver\n"); |
| break; |
| case 12: |
| cli_dbgmsg("Subsystem: EFI runtime driver\n"); |
| break; |
| default: |
| cli_warnmsg("Unknown subsystem in PE header (0x%x)\n", pe_plus ? EC16(optional_hdr64.Subsystem) : EC16(optional_hdr32.Subsystem)); |
| } |
| |
| cli_dbgmsg("------------------------------------\n"); |
| |
| if (DETECT_BROKEN && !native && (!(pe_plus?EC32(optional_hdr64.SectionAlignment):EC32(optional_hdr32.SectionAlignment)) || (pe_plus?EC32(optional_hdr64.SectionAlignment):EC32(optional_hdr32.SectionAlignment))%0x1000)) { |
| cli_dbgmsg("Bad virtual alignemnt\n"); |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| |
| if (DETECT_BROKEN && !native && (!(pe_plus?EC32(optional_hdr64.FileAlignment):EC32(optional_hdr32.FileAlignment)) || (pe_plus?EC32(optional_hdr64.FileAlignment):EC32(optional_hdr32.FileAlignment))%0x200)) { |
| cli_dbgmsg("Bad file alignemnt\n"); |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| |
| if(fstat(desc, &sb) == -1) { |
| cli_dbgmsg("fstat failed\n"); |
| return CL_EIO; |
| } |
| |
| fsize = sb.st_size; |
| |
| section_hdr = (struct pe_image_section_hdr *) cli_calloc(nsections, sizeof(struct pe_image_section_hdr)); |
| |
| if(!section_hdr) { |
| cli_dbgmsg("Can't allocate memory for section headers\n"); |
| return CL_EMEM; |
| } |
| |
| exe_sections = (struct cli_exe_section *) cli_calloc(nsections, sizeof(struct cli_exe_section)); |
| |
| if(!exe_sections) { |
| cli_dbgmsg("Can't allocate memory for section headers\n"); |
| free(section_hdr); |
| return CL_EMEM; |
| } |
| |
| valign = (pe_plus)?EC32(optional_hdr64.SectionAlignment):EC32(optional_hdr32.SectionAlignment); |
| falign = (pe_plus)?EC32(optional_hdr64.FileAlignment):EC32(optional_hdr32.FileAlignment); |
| |
| if(cli_readn(desc, section_hdr, sizeof(struct pe_image_section_hdr)*nsections) != (int)(nsections*sizeof(struct pe_image_section_hdr))) { |
| cli_dbgmsg("Can't read section header\n"); |
| cli_dbgmsg("Possibly broken PE file\n"); |
| free(section_hdr); |
| free(exe_sections); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| for(i = 0; falign!=0x200 && i<nsections; i++) { |
| /* file alignment fallback mode - blah */ |
| if (falign && section_hdr[i].SizeOfRawData && EC32(section_hdr[i].PointerToRawData)%falign && !(EC32(section_hdr[i].PointerToRawData)%0x200)) { |
| cli_dbgmsg("Found misaligned section, using 0x200\n"); |
| falign = 0x200; |
| } |
| } |
| |
| hdr_size = PESALIGN(hdr_size, valign); /* Aligned headers virtual size */ |
| |
| for(i = 0; i < nsections; i++) { |
| strncpy(sname, (char *) section_hdr[i].Name, 8); |
| sname[8] = 0; |
| exe_sections[i].rva = PEALIGN(EC32(section_hdr[i].VirtualAddress), valign); |
| exe_sections[i].vsz = PESALIGN(EC32(section_hdr[i].VirtualSize), valign); |
| exe_sections[i].raw = PEALIGN(EC32(section_hdr[i].PointerToRawData), falign); |
| exe_sections[i].rsz = PESALIGN(EC32(section_hdr[i].SizeOfRawData), falign); |
| exe_sections[i].chr = EC32(section_hdr[i].Characteristics); |
| exe_sections[i].urva = EC32(section_hdr[i].VirtualAddress); /* Just in case */ |
| exe_sections[i].uvsz = EC32(section_hdr[i].VirtualSize); |
| exe_sections[i].uraw = EC32(section_hdr[i].PointerToRawData); |
| exe_sections[i].ursz = EC32(section_hdr[i].SizeOfRawData); |
| |
| if (!exe_sections[i].vsz && exe_sections[i].rsz) |
| exe_sections[i].vsz=PESALIGN(exe_sections[i].ursz, valign); |
| |
| if (exe_sections[i].rsz && fsize>exe_sections[i].raw && !CLI_ISCONTAINED(0, (uint32_t) fsize, exe_sections[i].raw, exe_sections[i].rsz)) |
| exe_sections[i].rsz = fsize - exe_sections[i].raw; |
| |
| cli_dbgmsg("Section %d\n", i); |
| cli_dbgmsg("Section name: %s\n", sname); |
| cli_dbgmsg("Section data (from headers - in memory)\n"); |
| cli_dbgmsg("VirtualSize: 0x%x 0x%x\n", exe_sections[i].uvsz, exe_sections[i].vsz); |
| cli_dbgmsg("VirtualAddress: 0x%x 0x%x\n", exe_sections[i].urva, exe_sections[i].rva); |
| cli_dbgmsg("SizeOfRawData: 0x%x 0x%x\n", exe_sections[i].ursz, exe_sections[i].rsz); |
| cli_dbgmsg("PointerToRawData: 0x%x 0x%x\n", exe_sections[i].uraw, exe_sections[i].raw); |
| |
| if(exe_sections[i].chr & 0x20) { |
| cli_dbgmsg("Section contains executable code\n"); |
| |
| if(exe_sections[i].vsz < exe_sections[i].rsz) { |
| cli_dbgmsg("Section contains free space\n"); |
| /* |
| cli_dbgmsg("Dumping %d bytes\n", section_hdr.SizeOfRawData - section_hdr.VirtualSize); |
| ddump(desc, section_hdr.PointerToRawData + section_hdr.VirtualSize, section_hdr.SizeOfRawData - section_hdr.VirtualSize, cli_gentemp(NULL)); |
| */ |
| |
| } |
| } |
| |
| if(exe_sections[i].chr & 0x20000000) |
| cli_dbgmsg("Section's memory is executable\n"); |
| |
| if(exe_sections[i].chr & 0x80000000) |
| cli_dbgmsg("Section's memory is writeable\n"); |
| |
| cli_dbgmsg("------------------------------------\n"); |
| |
| if (DETECT_BROKEN && (exe_sections[i].urva % valign)) { /* Bad virtual alignment */ |
| cli_dbgmsg("VirtualAddress is misaligned\n"); |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| free(section_hdr); |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| |
| if (exe_sections[i].rsz) { /* Don't bother with virtual only sections */ |
| if (exe_sections[i].raw >= fsize) { /* really broken */ |
| cli_dbgmsg("Broken PE file - Section %d starts beyond the end of file (Offset@ %d, Total filesize %d)\n", i, exe_sections[i].raw, fsize); |
| free(section_hdr); |
| free(exe_sections); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; /* no ninjas to see here! move along! */ |
| } |
| |
| if(SCAN_ALGO && (DCONF & PE_CONF_POLIPOS) && !*sname && exe_sections[i].vsz > 40000 && exe_sections[i].vsz < 70000 && exe_sections[i].chr == 0xe0000060) polipos = i; |
| |
| /* check MD5 section sigs */ |
| md5_sect = ctx->engine->md5_sect; |
| if((DCONF & PE_CONF_MD5SECT) && md5_sect) { |
| found = 0; |
| for(j = 0; j < md5_sect->soff_len && md5_sect->soff[j] <= exe_sections[i].rsz; j++) { |
| if(md5_sect->soff[j] == exe_sections[i].rsz) { |
| unsigned char md5_dig[16]; |
| if(cli_md5sect(desc, &exe_sections[i], md5_dig) && cli_bm_scanbuff(md5_dig, 16, ctx->virname, ctx->engine->md5_sect, 0, 0, -1) == CL_VIRUS) { |
| free(section_hdr); |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| break; |
| } |
| } |
| } |
| } |
| |
| if(!i) { |
| if (DETECT_BROKEN && exe_sections[i].urva!=hdr_size) { /* Bad first section RVA */ |
| cli_dbgmsg("First section is in the wrong place\n"); |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| free(section_hdr); |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| min = exe_sections[i].rva; |
| max = exe_sections[i].rva + exe_sections[i].rsz; |
| } else { |
| if (DETECT_BROKEN && exe_sections[i].urva - exe_sections[i-1].urva != exe_sections[i-1].vsz) { /* No holes, no overlapping, no virtual disorder */ |
| cli_dbgmsg("Virtually misplaced section (wrong order, overlapping, non contiguous)\n"); |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| free(section_hdr); |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| if(exe_sections[i].rva < min) |
| min = exe_sections[i].rva; |
| |
| if(exe_sections[i].rva + exe_sections[i].rsz > max) |
| max = exe_sections[i].rva + exe_sections[i].rsz; |
| } |
| } |
| |
| free(section_hdr); |
| |
| if(!(ep = cli_rawaddr(vep, exe_sections, nsections, &err, fsize, hdr_size)) && err) { |
| cli_dbgmsg("EntryPoint out of file\n"); |
| free(exe_sections); |
| if(DETECT_BROKEN) { |
| if(ctx->virname) |
| *ctx->virname = "Broken.Executable"; |
| return CL_VIRUS; |
| } |
| return CL_CLEAN; |
| } |
| |
| cli_dbgmsg("EntryPoint offset: 0x%x (%d)\n", ep, ep); |
| |
| if(pe_plus) { /* Do not continue for PE32+ files */ |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| lseek(desc, ep, SEEK_SET); |
| epsize = cli_readn(desc, epbuff, 4096); |
| |
| /* Attempt to detect some popular polymorphic viruses */ |
| |
| /* W32.Parite.B */ |
| if(SCAN_ALGO && (DCONF & PE_CONF_PARITE) && !dll && epsize == 4096 && ep == exe_sections[nsections - 1].raw) { |
| const char *pt = cli_memstr(epbuff, 4040, "\x47\x65\x74\x50\x72\x6f\x63\x41\x64\x64\x72\x65\x73\x73\x00", 15); |
| if(pt) { |
| pt += 15; |
| if((((uint32_t)cli_readint32(pt) ^ (uint32_t)cli_readint32(pt + 4)) == 0x505a4f) && (((uint32_t)cli_readint32(pt + 8) ^ (uint32_t)cli_readint32(pt + 12)) == 0xffffb) && (((uint32_t)cli_readint32(pt + 16) ^ (uint32_t)cli_readint32(pt + 20)) == 0xb8)) { |
| *ctx->virname = "W32.Parite.B"; |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| } |
| } |
| |
| /* Kriz */ |
| if(SCAN_ALGO && (DCONF & PE_CONF_KRIZ) && epsize >= 200 && CLI_ISCONTAINED(exe_sections[nsections - 1].raw, exe_sections[nsections - 1].rsz, ep, 0x0fd2) && epbuff[1]=='\x9c' && epbuff[2]=='\x60') { |
| enum {KZSTRASH,KZSCDELTA,KZSPDELTA,KZSGETSIZE,KZSXORPRFX,KZSXOR,KZSDDELTA,KZSLOOP,KZSTOP}; |
| uint8_t kzs[] = {KZSTRASH,KZSCDELTA,KZSPDELTA,KZSGETSIZE,KZSTRASH,KZSXORPRFX,KZSXOR,KZSTRASH,KZSDDELTA,KZSTRASH,KZSLOOP,KZSTOP}; |
| uint8_t *kzstate = kzs; |
| uint8_t *kzcode = (uint8_t *)epbuff + 3; |
| uint8_t kzdptr=0xff, kzdsize=0xff; |
| int kzlen = 197, kzinitlen=0xffff, kzxorlen=-1; |
| cli_dbgmsg("in kriz\n"); |
| |
| while(*kzstate!=KZSTOP) { |
| uint8_t op; |
| if(kzlen<=6) break; |
| op = *kzcode++; |
| kzlen--; |
| switch (*kzstate) { |
| case KZSTRASH: case KZSGETSIZE: { |
| int opsz=0; |
| switch(op) { |
| case 0x81: |
| kzcode+=5; |
| kzlen-=5; |
| break; |
| case 0xb8: case 0xb9: case 0xba: case 0xbb: case 0xbd: case 0xbe: case 0xbf: |
| if(*kzstate==KZSGETSIZE && cli_readint32(kzcode)==0x0fd2) { |
| kzinitlen = kzlen-5; |
| kzdsize=op-0xb8; |
| kzstate++; |
| op=4; /* fake the register to avoid breaking out */ |
| cli_dbgmsg("kriz: using #%d as size counter\n", kzdsize); |
| } |
| opsz=4; |
| case 0x48: case 0x49: case 0x4a: case 0x4b: case 0x4d: case 0x4e: case 0x4f: |
| op&=7; |
| if(op!=kzdptr && op!=kzdsize) { |
| kzcode+=opsz; |
| kzlen-=opsz; |
| break; |
| } |
| default: |
| kzcode--; |
| kzlen++; |
| kzstate++; |
| } |
| break; |
| } |
| case KZSCDELTA: |
| if(op==0xe8 && (uint32_t)cli_readint32(kzcode) < 0xff) { |
| kzlen-=*kzcode+4; |
| kzcode+=*kzcode+4; |
| kzstate++; |
| } else *kzstate=KZSTOP; |
| break; |
| case KZSPDELTA: |
| if((op&0xf8)==0x58 && (kzdptr=op-0x58)!=4) { |
| kzstate++; |
| cli_dbgmsg("kriz: using #%d as pointer\n", kzdptr); |
| } else *kzstate=KZSTOP; |
| break; |
| case KZSXORPRFX: |
| kzstate++; |
| if(op==0x3e) break; |
| case KZSXOR: |
| if (op==0x80 && *kzcode==kzdptr+0xb0) { |
| kzxorlen=kzlen; |
| kzcode+=+6; |
| kzlen-=+6; |
| kzstate++; |
| } else *kzstate=KZSTOP; |
| break; |
| case KZSDDELTA: |
| if (op==kzdptr+0x48) kzstate++; |
| else *kzstate=KZSTOP; |
| break; |
| case KZSLOOP: |
| if (op==kzdsize+0x48 && *kzcode==0x75 && kzlen-(int8_t)kzcode[1]-3<=kzinitlen && kzlen-(int8_t)kzcode[1]>=kzxorlen) { |
| *ctx->virname = "W32.Kriz"; |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| cli_dbgmsg("kriz: loop out of bounds, corrupted sample?\n"); |
| kzstate++; |
| } |
| } |
| } |
| |
| /* W32.Magistr.A/B */ |
| if(SCAN_ALGO && (DCONF & PE_CONF_MAGISTR) && !dll && (nsections>1) && (exe_sections[nsections - 1].chr & 0x80000000)) { |
| uint32_t rsize, vsize, dam = 0; |
| |
| vsize = exe_sections[nsections - 1].uvsz; |
| rsize = exe_sections[nsections - 1].rsz; |
| if(rsize < exe_sections[nsections - 1].ursz) { |
| rsize = exe_sections[nsections - 1].ursz; |
| dam = 1; |
| } |
| |
| if(vsize >= 0x612c && rsize >= 0x612c && ((vsize & 0xff) == 0xec)) { |
| int bw = rsize < 0x7000 ? rsize : 0x7000; |
| |
| lseek(desc, exe_sections[nsections - 1].raw + rsize - bw, SEEK_SET); |
| if(cli_readn(desc, buff, 4096) == 4096) { |
| if(cli_memstr(buff, 4091, "\xe8\x2c\x61\x00\x00", 5)) { |
| *ctx->virname = dam ? "W32.Magistr.A.dam" : "W32.Magistr.A"; |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| } |
| |
| } else if(rsize >= 0x7000 && vsize >= 0x7000 && ((vsize & 0xff) == 0xed)) { |
| int bw = rsize < 0x8000 ? rsize : 0x8000; |
| |
| lseek(desc, exe_sections[nsections - 1].raw + rsize - bw, SEEK_SET); |
| if(cli_readn(desc, buff, 4096) == 4096) { |
| if(cli_memstr(buff, 4091, "\xe8\x04\x72\x00\x00", 5)) { |
| *ctx->virname = dam ? "W32.Magistr.B.dam" : "W32.Magistr.B"; |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| } |
| } |
| } |
| |
| /* W32.Polipos.A */ |
| while(polipos && !dll && nsections > 2 && nsections < 13 && e_lfanew <= 0x800 && (EC16(optional_hdr32.Subsystem) == 2 || EC16(optional_hdr32.Subsystem) == 3) && EC16(file_hdr.Machine) == 0x14c && optional_hdr32.SizeOfStackReserve >= 0x80000) { |
| uint32_t jump, jold, *jumps = NULL; |
| uint8_t *code; |
| unsigned int xsjs = 0; |
| |
| if(exe_sections[0].rsz > CLI_MAX_ALLOCATION) break; |
| if(!cli_seeksect(desc, &exe_sections[0])) break; |
| if(!(code=cli_malloc(exe_sections[0].rsz))) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| if(cli_readn(desc, code, exe_sections[0].rsz)!=exe_sections[0].rsz) { |
| free(exe_sections); |
| return CL_EIO; |
| } |
| for(i=0; i<exe_sections[0].rsz - 5; i++) { |
| if((uint8_t)(code[i]-0xe8) > 1) continue; |
| jump = cli_rawaddr(exe_sections[0].rva+i+5+cli_readint32(&code[i+1]), exe_sections, nsections, &err, fsize, hdr_size); |
| if(err || !CLI_ISCONTAINED(exe_sections[polipos].raw, exe_sections[polipos].rsz, jump, 9)) continue; |
| if(xsjs % 128 == 0) { |
| if(xsjs == 1280) break; |
| if(!(jumps=(uint32_t *)cli_realloc2(jumps, (xsjs+128)*sizeof(uint32_t)))) { |
| free(code); |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| } |
| j=0; |
| for(; j<xsjs; j++) { |
| if(jumps[j]<jump) continue; |
| if(jumps[j]==jump) { |
| xsjs--; |
| break; |
| } |
| jold=jumps[j]; |
| jumps[j]=jump; |
| jump=jold; |
| } |
| jumps[j]=jump; |
| xsjs++; |
| } |
| free(code); |
| if(!xsjs) break; |
| cli_dbgmsg("Polipos: Checking %d xsect jump(s)\n", xsjs); |
| for(i=0;i<xsjs;i++) { |
| lseek(desc, jumps[i], SEEK_SET); |
| if(cli_readn(desc, buff, 9) != 9) continue; |
| if((jump=cli_readint32(buff))==0x60ec8b55 || (buff[4]=='\xec' && ((jump==0x83ec8b55 && buff[6]=='\x60') || (jump==0x81ec8b55 && !buff[7] && !buff[8])))) { |
| *ctx->virname = "W32.Polipos.A"; |
| free(jumps); |
| free(exe_sections); |
| return CL_VIRUS; |
| } |
| } |
| free(jumps); |
| break; |
| } |
| |
| |
| /* UPX, FSG, MEW support */ |
| |
| /* try to find the first section with physical size == 0 */ |
| found = 0; |
| if(DCONF & (PE_CONF_UPX | PE_CONF_FSG | PE_CONF_MEW)) { |
| for(i = 0; i < (unsigned int) nsections - 1; i++) { |
| if(!exe_sections[i].rsz && exe_sections[i].vsz && exe_sections[i + 1].rsz && exe_sections[i + 1].vsz) { |
| found = 1; |
| cli_dbgmsg("UPX/FSG/MEW: empty section found - assuming compression\n"); |
| break; |
| } |
| } |
| } |
| |
| /* MEW support */ |
| if (found && (DCONF & PE_CONF_MEW) && epsize>=16 && epbuff[0]=='\xe9') { |
| uint32_t fileoffset; |
| |
| fileoffset = (vep + cli_readint32(epbuff + 1) + 5); |
| while (fileoffset == 0x154 || fileoffset == 0x158) { |
| uint32_t offdiff, uselzma; |
| |
| cli_dbgmsg ("MEW: found MEW characteristics %08X + %08X + 5 = %08X\n", |
| cli_readint32(epbuff + 1), vep, cli_readint32(epbuff + 1) + vep + 5); |
| |
| if(lseek(desc, fileoffset, SEEK_SET) == -1) { |
| cli_dbgmsg("MEW: lseek() failed\n"); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| if((bytes = read(desc, buff, 0xb0)) != 0xb0) { |
| cli_dbgmsg("MEW: Can't read 0xb0 bytes at 0x%x (%d) %d\n", fileoffset, fileoffset, bytes); |
| break; |
| } |
| |
| if (fileoffset == 0x154) cli_dbgmsg("MEW: Win9x compatibility was set!\n"); |
| else cli_dbgmsg("MEW: Win9x compatibility was NOT set!\n"); |
| |
| if((offdiff = cli_readint32(buff+1) - EC32(optional_hdr32.ImageBase)) <= exe_sections[i + 1].rva || offdiff >= exe_sections[i + 1].rva + exe_sections[i + 1].raw - 4) { |
| cli_dbgmsg("MEW: ESI is not in proper section\n"); |
| break; |
| } |
| offdiff -= exe_sections[i + 1].rva; |
| |
| if(!cli_seeksect(desc, &exe_sections[i + 1])) { |
| free(exe_sections); |
| return CL_EIO; |
| } |
| ssize = exe_sections[i + 1].vsz; |
| dsize = exe_sections[i].vsz; |
| |
| cli_dbgmsg("MEW: ssize %08x dsize %08x offdiff: %08x\n", ssize, dsize, offdiff); |
| |
| CLI_UNPSIZELIMITS("MEW", MAX(ssize, dsize)); |
| CLI_UNPSIZELIMITS("MEW", MAX(ssize + dsize, exe_sections[i + 1].rsz)); |
| |
| /* allocate needed buffer */ |
| if (!(src = cli_calloc (ssize + dsize, sizeof(char)))) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if (exe_sections[i + 1].rsz < offdiff + 12 || exe_sections[i + 1].rsz > ssize) { |
| cli_dbgmsg("MEW: Size mismatch: %08x\n", exe_sections[i + 1].rsz); |
| free(src); |
| break; |
| } |
| |
| if((bytes = read(desc, src + dsize, exe_sections[i + 1].rsz)) != exe_sections[i + 1].rsz) { |
| cli_dbgmsg("MEW: Can't read %d bytes [read: %d]\n", exe_sections[i + 1].rsz, bytes); |
| free(exe_sections); |
| free(src); |
| return CL_EIO; |
| } |
| cli_dbgmsg("MEW: %d (%08x) bytes read\n", bytes, bytes); |
| |
| /* count offset to lzma proc, if lzma used, 0xe8 -> call */ |
| if (buff[0x7b] == '\xe8') { |
| if (!CLI_ISCONTAINED(exe_sections[1].rva, exe_sections[1].vsz, cli_readint32(buff + 0x7c) + fileoffset + 0x80, 4)) { |
| cli_dbgmsg("MEW: lzma proc out of bounds!\n"); |
| free(src); |
| break; /* to next unpacker in chain */ |
| } |
| uselzma = cli_readint32(buff + 0x7c) - (exe_sections[0].rva - fileoffset - 0x80); |
| } else { |
| uselzma = 0; |
| } |
| |
| CLI_UNPTEMP("MEW",(src,exe_sections,0)); |
| CLI_UNPRESULTS("MEW",(unmew11(i, src, offdiff, ssize, dsize, EC32(optional_hdr32.ImageBase), exe_sections[0].rva, uselzma, NULL, NULL, ndesc)),1,(src,0)); |
| break; |
| } |
| } |
| |
| if(epsize<168) { |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| if (found || upack) { |
| /* Check EP for UPX vs. FSG vs. Upack */ |
| |
| /* Upack 0.39 produces 2 types of executables |
| * 3 sections: | 2 sections (one empty, I don't chech found if !upack, since it's in OR above): |
| * mov esi, value | pusha |
| * lodsd | call $+0x9 |
| * push eax | |
| * |
| * Upack 1.1/1.2 Beta produces [based on 2 samples (sUx) provided by aCaB]: |
| * 2 sections |
| * mov esi, value |
| * loads |
| * mov edi, eax |
| * |
| * Upack unknown [sample 0297729] |
| * 3 sections |
| * mov esi, value |
| * push [esi] |
| * jmp |
| * |
| */ |
| /* upack 0.39-3s + sample 0151477*/ |
| while(((upack && nsections == 3) && /* 3 sections */ |
| (( |
| epbuff[0] == '\xbe' && cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase) > min && /* mov esi */ |
| epbuff[5] == '\xad' && epbuff[6] == '\x50' /* lodsd; push eax */ |
| ) |
| || |
| /* based on 0297729 sample from aCaB */ |
| (epbuff[0] == '\xbe' && cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase) > min && /* mov esi */ |
| epbuff[5] == '\xff' && epbuff[6] == '\x36' /* push [esi] */ |
| ) |
| )) |
| || |
| ((!upack && nsections == 2) && /* 2 sections */ |
| (( /* upack 0.39-2s */ |
| epbuff[0] == '\x60' && epbuff[1] == '\xe8' && cli_readint32(epbuff+2) == 0x9 /* pusha; call+9 */ |
| ) |
| || |
| ( /* upack 1.1/1.2, based on 2 samples */ |
| epbuff[0] == '\xbe' && cli_readint32(epbuff+1) - EC32(optional_hdr32.ImageBase) < min && /* mov esi */ |
| cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase) > 0 && |
| epbuff[5] == '\xad' && epbuff[6] == '\x8b' && epbuff[7] == '\xf8' /* loads; mov edi, eax */ |
| ) |
| )) |
| ) { |
| uint32_t vma, off; |
| int a,b,c; |
| |
| cli_dbgmsg("Upack characteristics found.\n"); |
| a = exe_sections[0].vsz; |
| b = exe_sections[1].vsz; |
| if (upack) { |
| cli_dbgmsg("Upack: var set\n"); |
| c = exe_sections[2].vsz; |
| ssize = exe_sections[0].ursz + exe_sections[0].uraw; |
| off = exe_sections[0].rva; |
| vma = EC32(optional_hdr32.ImageBase) + exe_sections[0].rva; |
| } else { |
| cli_dbgmsg("Upack: var NOT set\n"); |
| c = exe_sections[1].rva; |
| ssize = exe_sections[1].uraw; |
| off = 0; |
| vma = exe_sections[1].rva - exe_sections[1].uraw; |
| } |
| |
| dsize = a+b+c; |
| |
| CLI_UNPSIZELIMITS("Upack", MAX(MAX(dsize, ssize), exe_sections[1].ursz)); |
| |
| if (exe_sections[1].rva - off > dsize || exe_sections[1].rva - off > dsize - exe_sections[1].ursz || (upack && (exe_sections[2].rva - exe_sections[0].rva > dsize || exe_sections[2].rva - exe_sections[0].rva > dsize - ssize)) || ssize > dsize) { |
| cli_dbgmsg("Upack: probably malformed pe-header, skipping to next unpacker\n"); |
| break; |
| } |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| lseek(desc, 0, SEEK_SET); |
| if(read(desc, dest, ssize) != ssize) { |
| cli_dbgmsg("Upack: Can't read raw data of section 0\n"); |
| free(exe_sections); |
| free(dest); |
| return CL_EIO; |
| } |
| |
| if(upack) memmove(dest + exe_sections[2].rva - exe_sections[0].rva, dest, ssize); |
| |
| lseek(desc, exe_sections[1].uraw, SEEK_SET); |
| |
| if(read(desc, dest + exe_sections[1].rva - off, exe_sections[1].ursz) != exe_sections[1].ursz) { |
| cli_dbgmsg("Upack: Can't read raw data of section 1\n"); |
| free(exe_sections); |
| free(dest); |
| return CL_EIO; |
| } |
| |
| CLI_UNPTEMP("Upack",(dest,exe_sections,0)); |
| CLI_UNPRESULTS("Upack",(unupack(upack, dest, dsize, epbuff, vma, ep, EC32(optional_hdr32.ImageBase), exe_sections[0].rva, ndesc)),1,(dest,0)); |
| break; |
| } |
| } |
| |
| |
| while(found && (DCONF & PE_CONF_FSG) && epbuff[0] == '\x87' && epbuff[1] == '\x25') { |
| |
| /* FSG v2.0 support - thanks to aCaB ! */ |
| |
| uint32_t newesi, newedi, newebx, newedx; |
| |
| ssize = exe_sections[i + 1].rsz; |
| dsize = exe_sections[i].vsz; |
| |
| CLI_UNPSIZELIMITS("FSG", MAX(dsize, ssize)); |
| |
| if(ssize <= 0x19 || dsize <= ssize) { |
| cli_dbgmsg("FSG: Size mismatch (ssize: %d, dsize: %d)\n", ssize, dsize); |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| newedx = cli_readint32(epbuff + 2) - EC32(optional_hdr32.ImageBase); |
| if(!CLI_ISCONTAINED(exe_sections[i + 1].rva, exe_sections[i + 1].rsz, newedx, 4)) { |
| cli_dbgmsg("FSG: xchg out of bounds (%x), giving up\n", newedx); |
| break; |
| } |
| |
| if((src = (char *) cli_malloc(ssize)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if(!cli_seeksect(desc, &exe_sections[i + 1]) || (unsigned int) cli_readn(desc, src, ssize) != ssize) { |
| cli_dbgmsg("Can't read raw data of section %d\n", i + 1); |
| free(exe_sections); |
| free(src); |
| return CL_EIO; |
| } |
| |
| dest = src + newedx - exe_sections[i + 1].rva; |
| if(newedx < exe_sections[i + 1].rva || !CLI_ISCONTAINED(src, ssize, dest, 4)) { |
| cli_dbgmsg("FSG: New ESP out of bounds\n"); |
| free(src); |
| break; |
| } |
| |
| newedx = cli_readint32(dest) - EC32(optional_hdr32.ImageBase); |
| if(!CLI_ISCONTAINED(exe_sections[i + 1].rva, exe_sections[i + 1].rsz, newedx, 4)) { |
| cli_dbgmsg("FSG: New ESP (%x) is wrong\n", newedx); |
| free(src); |
| break; |
| } |
| |
| dest = src + newedx - exe_sections[i + 1].rva; |
| if(!CLI_ISCONTAINED(src, ssize, dest, 32)) { |
| cli_dbgmsg("FSG: New stack out of bounds\n"); |
| free(src); |
| break; |
| } |
| |
| newedi = cli_readint32(dest) - EC32(optional_hdr32.ImageBase); |
| newesi = cli_readint32(dest + 4) - EC32(optional_hdr32.ImageBase); |
| newebx = cli_readint32(dest + 16) - EC32(optional_hdr32.ImageBase); |
| newedx = cli_readint32(dest + 20); |
| |
| if(newedi != exe_sections[i].rva) { |
| cli_dbgmsg("FSG: Bad destination buffer (edi is %x should be %x)\n", newedi, exe_sections[i].rva); |
| free(src); |
| break; |
| } |
| |
| if(newesi < exe_sections[i + 1].rva || newesi - exe_sections[i + 1].rva >= exe_sections[i + 1].rsz) { |
| cli_dbgmsg("FSG: Source buffer out of section bounds\n"); |
| free(src); |
| break; |
| } |
| |
| if(!CLI_ISCONTAINED(exe_sections[i + 1].rva, exe_sections[i + 1].rsz, newebx, 16)) { |
| cli_dbgmsg("FSG: Array of functions out of bounds\n"); |
| free(src); |
| break; |
| } |
| |
| newedx=cli_readint32(newebx + 12 - exe_sections[i + 1].rva + src) - EC32(optional_hdr32.ImageBase); |
| cli_dbgmsg("FSG: found old EP @%x\n",newedx); |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| free(exe_sections); |
| free(src); |
| return CL_EMEM; |
| } |
| |
| CLI_UNPTEMP("FSG",(src,dest,exe_sections,0)); |
| CLI_UNPRESULTSFSG2("FSG",(unfsg_200(newesi - exe_sections[i + 1].rva + src, dest, ssize + exe_sections[i + 1].rva - newesi, dsize, newedi, EC32(optional_hdr32.ImageBase), newedx, ndesc)),1,(src,dest,0)); |
| break; |
| } |
| |
| |
| while(found && (DCONF & PE_CONF_FSG) && epbuff[0] == '\xbe' && cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase) < min) { |
| |
| /* FSG support - v. 1.33 (thx trog for the many samples) */ |
| |
| int sectcnt = 0; |
| char *support; |
| uint32_t newesi, newedi, oldep, gp, t; |
| struct cli_exe_section *sections; |
| |
| ssize = exe_sections[i + 1].rsz; |
| dsize = exe_sections[i].vsz; |
| |
| CLI_UNPSIZELIMITS("FSG", MAX(dsize, ssize)); |
| |
| if(ssize <= 0x19 || dsize <= ssize) { |
| cli_dbgmsg("FSG: Size mismatch (ssize: %d, dsize: %d)\n", ssize, dsize); |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| if(!(gp = cli_rawaddr(cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase), NULL, 0 , &err, fsize, hdr_size)) && err ) { |
| cli_dbgmsg("FSG: Support data out of padding area\n"); |
| break; |
| } |
| |
| lseek(desc, gp, SEEK_SET); |
| gp = exe_sections[i + 1].raw - gp; |
| |
| CLI_UNPSIZELIMITS("FSG", gp) |
| |
| if((support = (char *) cli_malloc(gp)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if((int)cli_readn(desc, support, gp) != (int)gp) { |
| cli_dbgmsg("Can't read %d bytes from padding area\n", gp); |
| free(exe_sections); |
| free(support); |
| return CL_EIO; |
| } |
| |
| /* newebx = cli_readint32(support) - EC32(optional_hdr32.ImageBase); Unused */ |
| newedi = cli_readint32(support + 4) - EC32(optional_hdr32.ImageBase); /* 1st dest */ |
| newesi = cli_readint32(support + 8) - EC32(optional_hdr32.ImageBase); /* Source */ |
| |
| if(newesi < exe_sections[i + 1].rva || newesi - exe_sections[i + 1].rva >= exe_sections[i + 1].rsz) { |
| cli_dbgmsg("FSG: Source buffer out of section bounds\n"); |
| free(support); |
| break; |
| } |
| |
| if(newedi != exe_sections[i].rva) { |
| cli_dbgmsg("FSG: Bad destination (is %x should be %x)\n", newedi, exe_sections[i].rva); |
| free(support); |
| break; |
| } |
| |
| /* Counting original sections */ |
| for(t = 12; t < gp - 4; t += 4) { |
| uint32_t rva = cli_readint32(support+t); |
| |
| if(!rva) |
| break; |
| |
| rva -= EC32(optional_hdr32.ImageBase)+1; |
| sectcnt++; |
| |
| if(rva % 0x1000) cli_dbgmsg("FSG: Original section %d is misaligned\n", sectcnt); |
| |
| if(rva < exe_sections[i].rva || rva - exe_sections[i].rva >= exe_sections[i].vsz) { |
| cli_dbgmsg("FSG: Original section %d is out of bounds\n", sectcnt); |
| break; |
| } |
| } |
| |
| if(t >= gp - 4 || cli_readint32(support + t)) { |
| free(support); |
| break; |
| } |
| |
| if((sections = (struct cli_exe_section *) cli_malloc((sectcnt + 1) * sizeof(struct cli_exe_section))) == NULL) { |
| free(exe_sections); |
| free(support); |
| return CL_EMEM; |
| } |
| |
| sections[0].rva = newedi; |
| for(t = 1; t <= (uint32_t)sectcnt; t++) |
| sections[t].rva = cli_readint32(support + 8 + t * 4) - 1 - EC32(optional_hdr32.ImageBase); |
| |
| free(support); |
| |
| if((src = (char *) cli_malloc(ssize)) == NULL) { |
| free(exe_sections); |
| free(sections); |
| return CL_EMEM; |
| } |
| |
| if(!cli_seeksect(desc, &exe_sections[i + 1]) || (unsigned int) cli_readn(desc, src, ssize) != ssize) { |
| cli_dbgmsg("Can't read raw data of section %d\n", i); |
| free(exe_sections); |
| free(sections); |
| free(src); |
| return CL_EIO; |
| } |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| free(exe_sections); |
| free(src); |
| free(sections); |
| return CL_EMEM; |
| } |
| |
| oldep = vep + 161 + 6 + cli_readint32(epbuff+163); |
| cli_dbgmsg("FSG: found old EP @%x\n", oldep); |
| |
| CLI_UNPTEMP("FSG",(src,dest,sections,exe_sections,0)); |
| CLI_UNPRESULTSFSG1("FSG",(unfsg_133(src + newesi - exe_sections[i + 1].rva, dest, ssize + exe_sections[i + 1].rva - newesi, dsize, sections, sectcnt, EC32(optional_hdr32.ImageBase), oldep, ndesc)),1,(src,dest,sections,0)); |
| break; /* were done with 1.33 */ |
| } |
| |
| |
| while(found && (DCONF & PE_CONF_FSG) && epbuff[0] == '\xbb' && cli_readint32(epbuff + 1) - EC32(optional_hdr32.ImageBase) < min && epbuff[5] == '\xbf' && epbuff[10] == '\xbe' && vep >= exe_sections[i + 1].rva && vep - exe_sections[i + 1].rva > exe_sections[i + 1].rva - 0xe0 ) { |
| |
| /* FSG support - v. 1.31 */ |
| |
| int sectcnt = 0; |
| uint32_t t; |
| uint32_t gp = cli_rawaddr(cli_readint32(epbuff+1) - EC32(optional_hdr32.ImageBase), NULL, 0 , &err, fsize, hdr_size); |
| char *support; |
| uint32_t newesi = cli_readint32(epbuff+11) - EC32(optional_hdr32.ImageBase); |
| uint32_t newedi = cli_readint32(epbuff+6) - EC32(optional_hdr32.ImageBase); |
| uint32_t oldep = vep - exe_sections[i + 1].rva; |
| struct cli_exe_section *sections; |
| |
| ssize = exe_sections[i + 1].rsz; |
| dsize = exe_sections[i].vsz; |
| |
| |
| if(err) { |
| cli_dbgmsg("FSG: Support data out of padding area\n"); |
| break; |
| } |
| |
| if(newesi < exe_sections[i + 1].rva || newesi - exe_sections[i + 1].rva >= exe_sections[i + 1].raw) { |
| cli_dbgmsg("FSG: Source buffer out of section bounds\n"); |
| break; |
| } |
| |
| if(newedi != exe_sections[i].rva) { |
| cli_dbgmsg("FSG: Bad destination (is %x should be %x)\n", newedi, exe_sections[i].rva); |
| break; |
| } |
| |
| CLI_UNPSIZELIMITS("FSG", MAX(dsize, ssize)); |
| |
| if(ssize <= 0x19 || dsize <= ssize) { |
| cli_dbgmsg("FSG: Size mismatch (ssize: %d, dsize: %d)\n", ssize, dsize); |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| lseek(desc, gp, SEEK_SET); |
| gp = exe_sections[i + 1].raw - gp; |
| |
| CLI_UNPSIZELIMITS("FSG", gp) |
| |
| if((support = (char *) cli_malloc(gp)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if(cli_readn(desc, support, gp) != (int)gp) { |
| cli_dbgmsg("Can't read %d bytes from padding area\n", gp); |
| free(exe_sections); |
| free(support); |
| return CL_EIO; |
| } |
| |
| /* Counting original sections */ |
| for(t = 0; t < gp - 2; t += 2) { |
| uint32_t rva = support[t]|(support[t+1]<<8); |
| |
| if (rva == 2 || rva == 1) |
| break; |
| |
| rva = ((rva-2)<<12) - EC32(optional_hdr32.ImageBase); |
| sectcnt++; |
| |
| if(rva < exe_sections[i].rva || rva - exe_sections[i].rva >= exe_sections[i].vsz) { |
| cli_dbgmsg("FSG: Original section %d is out of bounds\n", sectcnt); |
| break; |
| } |
| } |
| |
| if(t >= gp-10 || cli_readint32(support + t + 6) != 2) { |
| free(support); |
| break; |
| } |
| |
| if((sections = (struct cli_exe_section *) cli_malloc((sectcnt + 1) * sizeof(struct cli_exe_section))) == NULL) { |
| free(exe_sections); |
| free(support); |
| return CL_EMEM; |
| } |
| |
| sections[0].rva = newedi; |
| for(t = 0; t <= (uint32_t)sectcnt - 1; t++) { |
| sections[t+1].rva = (((support[t*2]|(support[t*2+1]<<8))-2)<<12)-EC32(optional_hdr32.ImageBase); |
| } |
| |
| free(support); |
| |
| if((src = (char *) cli_malloc(ssize)) == NULL) { |
| free(exe_sections); |
| free(sections); |
| return CL_EMEM; |
| } |
| |
| if(!cli_seeksect(desc, &exe_sections[i + 1]) || (unsigned int) cli_readn(desc, src, ssize) != ssize) { |
| cli_dbgmsg("FSG: Can't read raw data of section %d\n", i); |
| free(exe_sections); |
| free(sections); |
| free(src); |
| return CL_EIO; |
| } |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| free(exe_sections); |
| free(src); |
| free(sections); |
| return CL_EMEM; |
| } |
| |
| gp = 0xda + 6*(epbuff[16]=='\xe8'); |
| oldep = vep + gp + 6 + cli_readint32(src+gp+2+oldep); |
| cli_dbgmsg("FSG: found old EP @%x\n", oldep); |
| |
| CLI_UNPTEMP("FSG",(src,dest,sections,exe_sections,0)); |
| CLI_UNPRESULTSFSG1("FSG",(unfsg_133(src + newesi - exe_sections[i + 1].rva, dest, ssize + exe_sections[i + 1].rva - newesi, dsize, sections, sectcnt, EC32(optional_hdr32.ImageBase), oldep, ndesc)),1,(src,dest,sections,0)); |
| break; /* were done with 1.31 */ |
| } |
| |
| |
| if(found && (DCONF & PE_CONF_UPX)) { |
| |
| /* UPX support */ |
| |
| /* we assume (i + 1) is UPX1 */ |
| ssize = exe_sections[i + 1].rsz; |
| dsize = exe_sections[i].vsz + exe_sections[i + 1].vsz; |
| |
| CLI_UNPSIZELIMITS("UPX", MAX(dsize, ssize)); |
| |
| if(ssize <= 0x19 || dsize <= ssize || dsize > CLI_MAX_ALLOCATION ) { |
| cli_dbgmsg("UPX: Size mismatch or dsize too big (ssize: %d, dsize: %d)\n", ssize, dsize); |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| if((src = (char *) cli_malloc(ssize)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if((dest = (char *) cli_calloc(dsize + 8192, sizeof(char))) == NULL) { |
| free(exe_sections); |
| free(src); |
| return CL_EMEM; |
| } |
| |
| if(!cli_seeksect(desc, &exe_sections[i + 1]) || (unsigned int) cli_readn(desc, src, ssize) != ssize) { |
| cli_dbgmsg("UPX: Can't read raw data of section %d\n", i+1); |
| free(exe_sections); |
| free(src); |
| free(dest); |
| return CL_EIO; |
| } |
| |
| /* try to detect UPX code */ |
| if(cli_memstr(UPX_NRV2B, 24, epbuff + 0x69, 13) || cli_memstr(UPX_NRV2B, 24, epbuff + 0x69 + 8, 13)) { |
| cli_dbgmsg("UPX: Looks like a NRV2B decompression routine\n"); |
| upxfn = upx_inflate2b; |
| } else if(cli_memstr(UPX_NRV2D, 24, epbuff + 0x69, 13) || cli_memstr(UPX_NRV2D, 24, epbuff + 0x69 + 8, 13)) { |
| cli_dbgmsg("UPX: Looks like a NRV2D decompression routine\n"); |
| upxfn = upx_inflate2d; |
| } else if(cli_memstr(UPX_NRV2E, 24, epbuff + 0x69, 13) || cli_memstr(UPX_NRV2E, 24, epbuff + 0x69 + 8, 13)) { |
| cli_dbgmsg("UPX: Looks like a NRV2E decompression routine\n"); |
| upxfn = upx_inflate2e; |
| } |
| |
| if(upxfn) { |
| int skew = cli_readint32(epbuff + 2) - EC32(optional_hdr32.ImageBase) - exe_sections[i + 1].rva; |
| |
| if(epbuff[1] != '\xbe' || skew <= 0 || skew > 0xfff) { /* FIXME: legit skews?? */ |
| skew = 0; |
| if(upxfn(src, ssize, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep) >= 0) |
| upx_success = 1; |
| |
| } else { |
| cli_dbgmsg("UPX: UPX1 seems skewed by %d bytes\n", skew); |
| if(upxfn(src + skew, ssize - skew, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep-skew) >= 0 || upxfn(src, ssize, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep) >= 0) |
| upx_success = 1; |
| } |
| |
| if(upx_success) |
| cli_dbgmsg("UPX: Successfully decompressed\n"); |
| else |
| cli_dbgmsg("UPX: Preferred decompressor failed\n"); |
| } |
| |
| if(!upx_success && upxfn != upx_inflate2b) { |
| if(upx_inflate2b(src, ssize, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep) == -1 && upx_inflate2b(src + 0x15, ssize - 0x15, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep - 0x15) == -1) { |
| |
| cli_dbgmsg("UPX: NRV2B decompressor failed\n"); |
| } else { |
| upx_success = 1; |
| cli_dbgmsg("UPX: Successfully decompressed with NRV2B\n"); |
| } |
| } |
| |
| if(!upx_success && upxfn != upx_inflate2d) { |
| if(upx_inflate2d(src, ssize, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep) == -1 && upx_inflate2d(src + 0x15, ssize - 0x15, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep - 0x15) == -1) { |
| |
| cli_dbgmsg("UPX: NRV2D decompressor failed\n"); |
| } else { |
| upx_success = 1; |
| cli_dbgmsg("UPX: Successfully decompressed with NRV2D\n"); |
| } |
| } |
| |
| if(!upx_success && upxfn != upx_inflate2e) { |
| if(upx_inflate2e(src, ssize, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep) == -1 && upx_inflate2e(src + 0x15, ssize - 0x15, dest, &dsize, exe_sections[i].rva, exe_sections[i + 1].rva, vep - 0x15) == -1) { |
| cli_dbgmsg("UPX: NRV2E decompressor failed\n"); |
| } else { |
| upx_success = 1; |
| cli_dbgmsg("UPX: Successfully decompressed with NRV2E\n"); |
| } |
| } |
| |
| if(!upx_success) { |
| cli_dbgmsg("UPX: All decompressors failed\n"); |
| free(src); |
| free(dest); |
| } |
| } |
| |
| if(upx_success) { |
| free(src); |
| free(exe_sections); |
| |
| CLI_UNPTEMP("UPX/FSG",(dest,0)); |
| |
| if((unsigned int) write(ndesc, dest, dsize) != dsize) { |
| cli_dbgmsg("UPX/FSG: Can't write %d bytes\n", dsize); |
| free(tempfile); |
| free(dest); |
| close(ndesc); |
| return CL_EIO; |
| } |
| |
| free(dest); |
| fsync(ndesc); |
| lseek(ndesc, 0, SEEK_SET); |
| |
| if(cli_leavetemps_flag) |
| cli_dbgmsg("UPX/FSG: Decompressed data saved in %s\n", tempfile); |
| |
| cli_dbgmsg("***** Scanning decompressed file *****\n"); |
| if((ret = cli_magic_scandesc(ndesc, ctx)) == CL_VIRUS) { |
| close(ndesc); |
| CLI_TMPUNLK(); |
| free(tempfile); |
| return CL_VIRUS; |
| } |
| |
| close(ndesc); |
| CLI_TMPUNLK(); |
| free(tempfile); |
| return ret; |
| } |
| |
| |
| /* Petite */ |
| |
| if(epsize<200) { |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| found = 2; |
| |
| if(epbuff[0] != '\xb8' || (uint32_t) cli_readint32(epbuff + 1) != exe_sections[nsections - 1].rva + EC32(optional_hdr32.ImageBase)) { |
| if(nsections < 2 || epbuff[0] != '\xb8' || (uint32_t) cli_readint32(epbuff + 1) != exe_sections[nsections - 2].rva + EC32(optional_hdr32.ImageBase)) |
| found = 0; |
| else |
| found = 1; |
| } |
| |
| if(found && (DCONF & PE_CONF_PETITE)) { |
| cli_dbgmsg("Petite: v2.%d compression detected\n", found); |
| |
| if(cli_readint32(epbuff + 0x80) == 0x163c988d) { |
| cli_dbgmsg("Petite: level zero compression is not supported yet\n"); |
| } else { |
| dsize = max - min; |
| |
| CLI_UNPSIZELIMITS("Petite", dsize); |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| cli_dbgmsg("Petite: Can't allocate %d bytes\n", dsize); |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| for(i = 0 ; i < nsections; i++) { |
| if(exe_sections[i].raw) { |
| if(!cli_seeksect(desc, &exe_sections[i]) || (unsigned int) cli_readn(desc, dest + exe_sections[i].rva - min, exe_sections[i].ursz) != exe_sections[i].ursz) { |
| free(exe_sections); |
| free(dest); |
| return CL_EIO; |
| } |
| } |
| } |
| |
| CLI_UNPTEMP("Petite",(dest,exe_sections,0)); |
| CLI_UNPRESULTS("Petite",(petite_inflate2x_1to9(dest, min, max - min, exe_sections, nsections - (found == 1 ? 1 : 0), EC32(optional_hdr32.ImageBase),vep, ndesc, found, EC32(optional_hdr32.DataDirectory[2].VirtualAddress),EC32(optional_hdr32.DataDirectory[2].Size))),0,(dest,0)); |
| } |
| } |
| |
| /* PESpin 1.1 */ |
| |
| if((DCONF & PE_CONF_PESPIN) && nsections > 1 && |
| vep >= exe_sections[nsections - 1].rva && |
| vep < exe_sections[nsections - 1].rva + exe_sections[nsections - 1].rsz - 0x3217 - 4 && |
| memcmp(epbuff+4, "\xe8\x00\x00\x00\x00\x8b\x1c\x24\x83\xc3", 10) == 0) { |
| |
| char *spinned; |
| |
| CLI_UNPSIZELIMITS("PEspin", fsize); |
| |
| if((spinned = (char *) cli_malloc(fsize)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| lseek(desc, 0, SEEK_SET); |
| if((size_t) cli_readn(desc, spinned, fsize) != fsize) { |
| cli_dbgmsg("PESpin: Can't read %d bytes\n", fsize); |
| free(spinned); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| CLI_UNPTEMP("PESpin",(spinned,exe_sections,0)); |
| CLI_UNPRESULTS_("PEspin",SPINCASE(),(unspin(spinned, fsize, exe_sections, nsections - 1, vep, ndesc, ctx)),0,(spinned,0)); |
| } |
| |
| |
| /* yC 1.3 */ |
| |
| if((DCONF & PE_CONF_YC) && nsections > 1 && |
| EC32(optional_hdr32.AddressOfEntryPoint) == exe_sections[nsections - 1].rva + 0x60 && |
| memcmp(epbuff, "\x55\x8B\xEC\x53\x56\x57\x60\xE8\x00\x00\x00\x00\x5D\x81\xED\x6C\x28\x40\x00\xB9\x5D\x34\x40\x00\x81\xE9\xC6\x28\x40\x00\x8B\xD5\x81\xC2\xC6\x28\x40\x00\x8D\x3A\x8B\xF7\x33\xC0\xEB\x04\x90\xEB\x01\xC2\xAC", 51) == 0 && fsize >= exe_sections[nsections - 1].raw + 0xC6 + 0xb97) { |
| |
| char *spinned; |
| |
| if((spinned = (char *) cli_malloc(fsize)) == NULL) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| lseek(desc, 0, SEEK_SET); |
| if((size_t) cli_readn(desc, spinned, fsize) != fsize) { |
| cli_dbgmsg("yC: Can't read %d bytes\n", fsize); |
| free(spinned); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| CLI_UNPTEMP("yC",(spinned,exe_sections,0)); |
| CLI_UNPRESULTS("yC",(yc_decrypt(spinned, fsize, exe_sections, nsections-1, e_lfanew, ndesc)),0,(spinned,0)); |
| } |
| |
| |
| /* WWPack */ |
| |
| if((DCONF & PE_CONF_WWPACK) && nsections > 1 && |
| exe_sections[nsections-1].raw>0x2b1 && |
| vep == exe_sections[nsections - 1].rva && |
| exe_sections[nsections - 1].rva + exe_sections[nsections - 1].rsz == max && |
| memcmp(epbuff, "\x53\x55\x8b\xe8\x33\xdb\xeb", 7) == 0 && |
| memcmp(epbuff+0x68, "\xe8\x00\x00\x00\x00\x58\x2d\x6d\x00\x00\x00\x50\x60\x33\xc9\x50\x58\x50\x50", 19) == 0) { |
| uint32_t headsize=exe_sections[nsections - 1].raw; |
| char *dest, *wwp; |
| |
| for(i = 0 ; i < (unsigned int)nsections-1; i++) |
| if (exe_sections[i].raw<headsize) headsize=exe_sections[i].raw; |
| |
| dsize = max-min+headsize-exe_sections[nsections - 1].rsz; |
| |
| CLI_UNPSIZELIMITS("WWPack", dsize); |
| |
| if((dest = (char *) cli_calloc(dsize, sizeof(char))) == NULL) { |
| cli_dbgmsg("WWPack: Can't allocate %d bytes\n", dsize); |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| lseek(desc, 0, SEEK_SET); |
| if((size_t) cli_readn(desc, dest, headsize) != headsize) { |
| cli_dbgmsg("WWPack: Can't read %d bytes from headers\n", headsize); |
| free(dest); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| for(i = 0 ; i < (unsigned int)nsections-1; i++) { |
| if(exe_sections[i].rsz) { |
| if(!cli_seeksect(desc, &exe_sections[i]) || (unsigned int) cli_readn(desc, dest + headsize + exe_sections[i].rva - min, exe_sections[i].rsz) != exe_sections[i].rsz) { |
| free(dest); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| } |
| } |
| |
| if((wwp = (char *) cli_calloc(exe_sections[nsections - 1].rsz, sizeof(char))) == NULL) { |
| cli_dbgmsg("WWPack: Can't allocate %d bytes\n", exe_sections[nsections - 1].rsz); |
| free(dest); |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| |
| if(!cli_seeksect(desc, &exe_sections[nsections - 1]) || (size_t) cli_readn(desc, wwp, exe_sections[nsections - 1].rsz) != exe_sections[nsections - 1].rsz) { |
| cli_dbgmsg("WWPack: Can't read %d bytes from wwpack sect\n", exe_sections[nsections - 1].rsz); |
| free(dest); |
| free(wwp); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| if (!wwunpack(dest, dsize, headsize, min, exe_sections[nsections-1].rva, e_lfanew, wwp, exe_sections[nsections - 1].rsz, nsections-1)) { |
| |
| free(wwp); |
| |
| CLI_UNPTEMP("WWPack",(dest,exe_sections,0)); |
| |
| if((unsigned int) write(ndesc, dest, dsize) != dsize) { |
| cli_dbgmsg("WWPack: Can't write %d bytes\n", dsize); |
| close(ndesc); |
| free(tempfile); |
| free(dest); |
| free(exe_sections); |
| return CL_EIO; |
| } |
| |
| free(dest); |
| if (cli_leavetemps_flag) |
| cli_dbgmsg("WWPack: Unpacked and rebuilt executable saved in %s\n", tempfile); |
| else |
| cli_dbgmsg("WWPack: Unpacked and rebuilt executable\n"); |
| |
| fsync(ndesc); |
| lseek(ndesc, 0, SEEK_SET); |
| |
| if(cli_magic_scandesc(ndesc, ctx) == CL_VIRUS) { |
| free(exe_sections); |
| close(ndesc); |
| if(!cli_leavetemps_flag) |
| unlink(tempfile); |
| free(tempfile); |
| return CL_VIRUS; |
| } |
| |
| close(ndesc); |
| if(!cli_leavetemps_flag) |
| unlink(tempfile); |
| free(tempfile); |
| } else { |
| free(wwp); |
| free(dest); |
| cli_dbgmsg("WWPpack: Decompression failed\n"); |
| } |
| } |
| |
| |
| /* ASPACK support */ |
| while((DCONF & PE_CONF_ASPACK) && ep+58+0x70e < fsize && !memcmp(epbuff,"\x60\xe8\x03\x00\x00\x00\xe9\xeb",8)) { |
| |
| if(epsize<0x3bf || memcmp(epbuff+0x3b9, "\x68\x00\x00\x00\x00\xc3",6)) break; |
| ssize = 0; |
| for(i=0 ; i< nsections ; i++) |
| if(ssize<exe_sections[i].rva+exe_sections[i].vsz) |
| ssize=exe_sections[i].rva+exe_sections[i].vsz; |
| if(!ssize) break; |
| |
| CLI_UNPSIZELIMITS("Aspack", ssize); |
| |
| if(!(src=(char *)cli_calloc(ssize, sizeof(char)))) { |
| free(exe_sections); |
| return CL_EMEM; |
| } |
| for(i = 0 ; i < (unsigned int)nsections; i++) { |
| if(!exe_sections[i].rsz) continue; |
| if(!cli_seeksect(desc, &exe_sections[i])) break; |
| if(!CLI_ISCONTAINED(src, ssize, src+exe_sections[i].rva, exe_sections[i].rsz)) break; |
| if(cli_readn(desc, src+exe_sections[i].rva, exe_sections[i].rsz)!=exe_sections[i].rsz) break; |
| } |
| if(i!=nsections) { |
| cli_dbgmsg("Aspack: Probably hacked/damaged Aspack file.\n"); |
| free(src); |
| break; |
| } |
| |
| CLI_UNPTEMP("Aspack",(src,exe_sections,0)); |
| CLI_UNPRESULTS("Aspack",(unaspack212((uint8_t *)src, ssize, exe_sections, nsections, vep-1, EC32(optional_hdr32.ImageBase), ndesc)),1,(src,0)); |
| break; |
| } |
| |
| /* NsPack */ |
| |
| while (DCONF & PE_CONF_NSPACK) { |
| uint32_t eprva = vep; |
| uint32_t start_of_stuff, ssize, dsize, rep = ep; |
| unsigned int nowinldr; |
| char nbuff[24]; |
| char *src=epbuff, *dest; |
| |
| if (*epbuff=='\xe9') { /* bitched headers */ |
| eprva = cli_readint32(epbuff+1)+vep+5; |
| if (!(rep = cli_rawaddr(eprva, exe_sections, nsections, &err, fsize, hdr_size)) && err) break; |
| if (lseek(desc, rep, SEEK_SET)==-1) break; |
| if (cli_readn(desc, nbuff, 24)!=24) break; |
| src = nbuff; |
| } |
| |
| if (memcmp(src, "\x9c\x60\xe8\x00\x00\x00\x00\x5d\xb8\x07\x00\x00\x00", 13)) break; |
| |
| nowinldr = 0x54-cli_readint32(src+17); |
| cli_dbgmsg("NsPack: Found *start_of_stuff @delta-%x\n", nowinldr); |
| |
| if (lseek(desc, rep-nowinldr, SEEK_SET)==-1) break; |
| if (cli_readn(desc, nbuff, 4)!=4) break; |
| start_of_stuff=rep+cli_readint32(nbuff); |
| if (lseek(desc, start_of_stuff, SEEK_SET)==-1) break; |
| if (cli_readn(desc, nbuff, 20)!=20) break; |
| src = nbuff; |
| if (!cli_readint32(nbuff)) { |
| start_of_stuff+=4; /* FIXME: more to do */ |
| src+=4; |
| } |
| |
| ssize = cli_readint32(src+5)|0xff; |
| dsize = cli_readint32(src+9); |
| |
| CLI_UNPSIZELIMITS("NsPack", MAX(ssize,dsize)); |
| |
| if ( !ssize || !dsize || dsize != exe_sections[0].vsz) break; |
| if (lseek(desc, start_of_stuff, SEEK_SET)==-1) break; |
| if (!(dest=cli_malloc(dsize))) break; |
| /* memset(dest, 0xfc, dsize); */ |
| |
| if (!(src=cli_malloc(ssize))) { |
| free(dest); |
| break; |
| } |
| /* memset(src, 0x00, ssize); */ |
| cli_readn(desc, src, ssize); |
| |
| eprva+=0x27a; |
| if (!(rep = cli_rawaddr(eprva, exe_sections, nsections, &err, fsize, hdr_size)) && err) { |
| free(dest); |
| free(src); |
| break; |
| } |
| if (lseek(desc, rep, SEEK_SET)==-1) { |
| free(dest); |
| free(src); |
| break; |
| } |
| if (cli_readn(desc, nbuff, 5)!=5) { |
| free(dest); |
| free(src); |
| break; |
| } |
| eprva=eprva+5+cli_readint32(nbuff+1); |
| cli_dbgmsg("NsPack: OEP = %08x\n", eprva); |
| |
| CLI_UNPTEMP("NsPack",(src,dest,exe_sections,0)); |
| CLI_UNPRESULTS("NsPack",(unspack(src, dest, ctx, exe_sections[0].rva, EC32(optional_hdr32.ImageBase), eprva, ndesc)),0,(src,dest,0)); |
| break; |
| } |
| |
| /* to be continued ... */ |
| |
| free(exe_sections); |
| return CL_CLEAN; |
| } |
| |
| int cli_peheader(int desc, struct cli_exe_info *peinfo) |
| { |
| uint16_t e_magic; /* DOS signature ("MZ") */ |
| uint32_t e_lfanew; /* address of new exe header */ |
| /* Obsolete - see below |
| uint32_t min = 0, max = 0; |
| */ |
| struct pe_image_file_hdr file_hdr; |
| union { |
| struct pe_image_optional_hdr64 opt64; |
| struct pe_image_optional_hdr32 opt32; |
| } pe_opt; |
| struct pe_image_section_hdr *section_hdr; |
| struct stat sb; |
| int i; |
| unsigned int err, pe_plus = 0; |
| uint32_t valign, falign, hdr_size; |
| size_t fsize; |
| |
| cli_dbgmsg("in cli_peheader\n"); |
| |
| if(fstat(desc, &sb) == -1) { |
| cli_dbgmsg("fstat failed\n"); |
| return -1; |
| } |
| |
| fsize = sb.st_size - peinfo->offset; |
| |
| if(cli_readn(desc, &e_magic, sizeof(e_magic)) != sizeof(e_magic)) { |
| cli_dbgmsg("Can't read DOS signature\n"); |
| return -1; |
| } |
| |
| if(EC16(e_magic) != IMAGE_DOS_SIGNATURE && EC16(e_magic) != IMAGE_DOS_SIGNATURE_OLD) { |
| cli_dbgmsg("Invalid DOS signature\n"); |
| return -1; |
| } |
| |
| lseek(desc, 58, SEEK_CUR); /* skip to the end of the DOS header */ |
| |
| if(cli_readn(desc, &e_lfanew, sizeof(e_lfanew)) != sizeof(e_lfanew)) { |
| cli_dbgmsg("Can't read new header address\n"); |
| /* truncated header? */ |
| return -1; |
| } |
| |
| e_lfanew = EC32(e_lfanew); |
| if(!e_lfanew) { |
| cli_dbgmsg("Not a PE file\n"); |
| return -1; |
| } |
| |
| if(lseek(desc, peinfo->offset + e_lfanew, SEEK_SET) < 0) { |
| /* probably not a PE file */ |
| cli_dbgmsg("Can't lseek to e_lfanew\n"); |
| return -1; |
| } |
| |
| if(cli_readn(desc, &file_hdr, sizeof(struct pe_image_file_hdr)) != sizeof(struct pe_image_file_hdr)) { |
| /* bad information in e_lfanew - probably not a PE file */ |
| cli_dbgmsg("Can't read file header\n"); |
| return -1; |
| } |
| |
| if(EC32(file_hdr.Magic) != IMAGE_NT_SIGNATURE) { |
| cli_dbgmsg("Invalid PE signature (probably NE file)\n"); |
| return -1; |
| } |
| |
| if ( (peinfo->nsections = EC16(file_hdr.NumberOfSections)) < 1 || peinfo->nsections > 96 ) return -1; |
| |
| if (EC16(file_hdr.SizeOfOptionalHeader) < sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("SizeOfOptionalHeader too small\n"); |
| return -1; |
| } |
| |
| if(cli_readn(desc, &optional_hdr32, sizeof(struct pe_image_optional_hdr32)) != sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("Can't read optional file header\n"); |
| return -1; |
| } |
| |
| if(EC32(optional_hdr64.Magic)==PE32P_SIGNATURE) { /* PE+ */ |
| if(EC16(file_hdr.SizeOfOptionalHeader)!=sizeof(struct pe_image_optional_hdr64)) { |
| cli_dbgmsg("Incorrect SizeOfOptionalHeader for PE32+\n"); |
| return -1; |
| } |
| if(cli_readn(desc, &optional_hdr32 + 1, sizeof(struct pe_image_optional_hdr64) - sizeof(struct pe_image_optional_hdr32)) != sizeof(struct pe_image_optional_hdr64) - sizeof(struct pe_image_optional_hdr32)) { |
| cli_dbgmsg("Can't read optional file header\n"); |
| return -1; |
| } |
| hdr_size = EC32(optional_hdr64.SizeOfHeaders); |
| pe_plus=1; |
| } else { /* PE */ |
| if (EC16(file_hdr.SizeOfOptionalHeader)!=sizeof(struct pe_image_optional_hdr32)) { |
| /* Seek to the end of the long header */ |
| lseek(desc, (EC16(file_hdr.SizeOfOptionalHeader)-sizeof(struct pe_image_optional_hdr32)), SEEK_CUR); |
| } |
| hdr_size = EC32(optional_hdr32.SizeOfHeaders); |
| } |
| |
| valign = (pe_plus)?EC32(optional_hdr64.SectionAlignment):EC32(optional_hdr32.SectionAlignment); |
| falign = (pe_plus)?EC32(optional_hdr64.FileAlignment):EC32(optional_hdr32.FileAlignment); |
| |
| hdr_size = PESALIGN(hdr_size, valign); |
| |
| peinfo->section = (struct cli_exe_section *) cli_calloc(peinfo->nsections, sizeof(struct cli_exe_section)); |
| |
| if(!peinfo->section) { |
| cli_dbgmsg("Can't allocate memory for section headers\n"); |
| return -1; |
| } |
| |
| section_hdr = (struct pe_image_section_hdr *) cli_calloc(peinfo->nsections, sizeof(struct pe_image_section_hdr)); |
| |
| if(!section_hdr) { |
| cli_dbgmsg("Can't allocate memory for section headers\n"); |
| free(peinfo->section); |
| peinfo->section = NULL; |
| return -1; |
| } |
| |
| if(cli_readn(desc, section_hdr, peinfo->nsections * sizeof(struct pe_image_section_hdr)) != peinfo->nsections * sizeof(struct pe_image_section_hdr)) { |
| cli_dbgmsg("Can't read section header\n"); |
| cli_dbgmsg("Possibly broken PE file\n"); |
| free(section_hdr); |
| free(peinfo->section); |
| peinfo->section = NULL; |
| return -1; |
| } |
| |
| for(i = 0; falign!=0x200 && i<peinfo->nsections; i++) { |
| /* file alignment fallback mode - blah */ |
| if (falign && section_hdr[i].SizeOfRawData && EC32(section_hdr[i].PointerToRawData)%falign && !(EC32(section_hdr[i].PointerToRawData)%0x200)) { |
| falign = 0x200; |
| } |
| } |
| |
| for(i = 0; i < peinfo->nsections; i++) { |
| peinfo->section[i].rva = PEALIGN(EC32(section_hdr[i].VirtualAddress), valign); |
| peinfo->section[i].vsz = PESALIGN(EC32(section_hdr[i].VirtualSize), valign); |
| peinfo->section[i].raw = PEALIGN(EC32(section_hdr[i].PointerToRawData), falign); |
| peinfo->section[i].rsz = PESALIGN(EC32(section_hdr[i].SizeOfRawData), falign); |
| |
| if (!peinfo->section[i].vsz && peinfo->section[i].rsz) |
| peinfo->section[i].vsz=PESALIGN(EC32(section_hdr[i].SizeOfRawData), valign); |
| |
| if (peinfo->section[i].rsz && !CLI_ISCONTAINED(0, (uint32_t) fsize, peinfo->section[i].raw, peinfo->section[i].rsz)) |
| peinfo->section[i].rsz = (fsize - peinfo->section[i].raw)*(fsize>peinfo->section[i].raw); |
| } |
| |
| if(pe_plus) |
| peinfo->ep = EC32(optional_hdr64.AddressOfEntryPoint); |
| else |
| peinfo->ep = EC32(optional_hdr32.AddressOfEntryPoint); |
| |
| if(!(peinfo->ep = cli_rawaddr(peinfo->ep, peinfo->section, peinfo->nsections, &err, fsize, hdr_size)) && err) { |
| cli_dbgmsg("Broken PE file\n"); |
| free(section_hdr); |
| free(peinfo->section); |
| peinfo->section = NULL; |
| return -1; |
| } |
| |
| free(section_hdr); |
| return 0; |
| } |