diff options
Diffstat (limited to 'contrib/elf2dmp/main.c')
| -rw-r--r-- | contrib/elf2dmp/main.c | 589 |
1 files changed, 589 insertions, 0 deletions
diff --git a/contrib/elf2dmp/main.c b/contrib/elf2dmp/main.c new file mode 100644 index 0000000000..9b93dab662 --- /dev/null +++ b/contrib/elf2dmp/main.c @@ -0,0 +1,589 @@ +/* + * Copyright (c) 2018 Virtuozzo International GmbH + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * + */ + +#include "qemu/osdep.h" +#include "err.h" +#include "addrspace.h" +#include "pe.h" +#include "pdb.h" +#include "kdbg.h" +#include "download.h" +#include "qemu/win_dump_defs.h" + +#define SYM_URL_BASE "https://msdl.microsoft.com/download/symbols/" +#define PDB_NAME "ntkrnlmp.pdb" + +#define INITIAL_MXCSR 0x1f80 + +typedef struct idt_desc { + uint16_t offset1; /* offset bits 0..15 */ + uint16_t selector; + uint8_t ist; + uint8_t type_attr; + uint16_t offset2; /* offset bits 16..31 */ + uint32_t offset3; /* offset bits 32..63 */ + uint32_t rsrvd; +} __attribute__ ((packed)) idt_desc_t; + +static uint64_t idt_desc_addr(idt_desc_t desc) +{ + return (uint64_t)desc.offset1 | ((uint64_t)desc.offset2 << 16) | + ((uint64_t)desc.offset3 << 32); +} + +static const uint64_t SharedUserData = 0xfffff78000000000; + +#define KUSD_OFFSET_SUITE_MASK 0x2d0 +#define KUSD_OFFSET_PRODUCT_TYPE 0x264 + +#define SYM_RESOLVE(base, r, s) ((s = pdb_resolve(base, r, #s)),\ + s ? printf(#s" = 0x%016lx\n", s) : eprintf("Failed to resolve "#s"\n"), s) + +static uint64_t rol(uint64_t x, uint64_t y) +{ + return (x << y) | (x >> (64 - y)); +} + +/* + * Decoding algorithm can be found in Volatility project + */ +static void kdbg_decode(uint64_t *dst, uint64_t *src, size_t size, + uint64_t kwn, uint64_t kwa, uint64_t kdbe) +{ + size_t i; + assert(size % sizeof(uint64_t) == 0); + for (i = 0; i < size / sizeof(uint64_t); i++) { + uint64_t block; + + block = src[i]; + block = rol(block ^ kwn, (uint8_t)kwn); + block = __builtin_bswap64(block ^ kdbe) ^ kwa; + dst[i] = block; + } +} + +static KDDEBUGGER_DATA64 *get_kdbg(uint64_t KernBase, struct pdb_reader *pdb, + struct va_space *vs, uint64_t KdDebuggerDataBlock) +{ + const char OwnerTag[4] = "KDBG"; + KDDEBUGGER_DATA64 *kdbg = NULL; + DBGKD_DEBUG_DATA_HEADER64 kdbg_hdr; + bool decode = false; + uint64_t kwn, kwa, KdpDataBlockEncoded; + + if (va_space_rw(vs, + KdDebuggerDataBlock + offsetof(KDDEBUGGER_DATA64, Header), + &kdbg_hdr, sizeof(kdbg_hdr), 0)) { + eprintf("Failed to extract KDBG header\n"); + return NULL; + } + + if (memcmp(&kdbg_hdr.OwnerTag, OwnerTag, sizeof(OwnerTag))) { + uint64_t KiWaitNever, KiWaitAlways; + + decode = true; + + if (!SYM_RESOLVE(KernBase, pdb, KiWaitNever) || + !SYM_RESOLVE(KernBase, pdb, KiWaitAlways) || + !SYM_RESOLVE(KernBase, pdb, KdpDataBlockEncoded)) { + return NULL; + } + + if (va_space_rw(vs, KiWaitNever, &kwn, sizeof(kwn), 0) || + va_space_rw(vs, KiWaitAlways, &kwa, sizeof(kwa), 0)) { + return NULL; + } + + printf("[KiWaitNever] = 0x%016lx\n", kwn); + printf("[KiWaitAlways] = 0x%016lx\n", kwa); + + /* + * If KDBG header can be decoded, KDBG size is available + * and entire KDBG can be decoded. + */ + printf("Decoding KDBG header...\n"); + kdbg_decode((uint64_t *)&kdbg_hdr, (uint64_t *)&kdbg_hdr, + sizeof(kdbg_hdr), kwn, kwa, KdpDataBlockEncoded); + + printf("Owner tag is \'%.4s\'\n", (char *)&kdbg_hdr.OwnerTag); + if (memcmp(&kdbg_hdr.OwnerTag, OwnerTag, sizeof(OwnerTag))) { + eprintf("Failed to decode KDBG header\n"); + return NULL; + } + } + + kdbg = malloc(kdbg_hdr.Size); + if (!kdbg) { + return NULL; + } + + if (va_space_rw(vs, KdDebuggerDataBlock, kdbg, kdbg_hdr.Size, 0)) { + eprintf("Failed to extract entire KDBG\n"); + return NULL; + } + + if (!decode) { + return kdbg; + } + + printf("Decoding KdDebuggerDataBlock...\n"); + kdbg_decode((uint64_t *)kdbg, (uint64_t *)kdbg, kdbg_hdr.Size, + kwn, kwa, KdpDataBlockEncoded); + + va_space_rw(vs, KdDebuggerDataBlock, kdbg, kdbg_hdr.Size, 1); + + return kdbg; +} + +static void win_context_init_from_qemu_cpu_state(WinContext *ctx, + QEMUCPUState *s) +{ + WinContext win_ctx = (WinContext){ + .ContextFlags = WIN_CTX_X64 | WIN_CTX_INT | WIN_CTX_SEG | WIN_CTX_CTL, + .MxCsr = INITIAL_MXCSR, + + .SegCs = s->cs.selector, + .SegSs = s->ss.selector, + .SegDs = s->ds.selector, + .SegEs = s->es.selector, + .SegFs = s->fs.selector, + .SegGs = s->gs.selector, + .EFlags = (uint32_t)s->rflags, + + .Rax = s->rax, + .Rbx = s->rbx, + .Rcx = s->rcx, + .Rdx = s->rdx, + .Rsp = s->rsp, + .Rbp = s->rbp, + .Rsi = s->rsi, + .Rdi = s->rdi, + .R8 = s->r8, + .R9 = s->r9, + .R10 = s->r10, + .R11 = s->r11, + .R12 = s->r12, + .R13 = s->r13, + .R14 = s->r14, + .R15 = s->r15, + + .Rip = s->rip, + .FltSave = { + .MxCsr = INITIAL_MXCSR, + }, + }; + + *ctx = win_ctx; +} + +/* + * Finds paging-structure hierarchy base, + * if previously set doesn't give access to kernel structures + */ +static int fix_dtb(struct va_space *vs, QEMU_Elf *qe) +{ + /* + * Firstly, test previously set DTB. + */ + if (va_space_resolve(vs, SharedUserData)) { + return 0; + } + + /* + * Secondly, find CPU which run system task. + */ + size_t i; + for (i = 0; i < qe->state_nr; i++) { + QEMUCPUState *s = qe->state[i]; + + if (is_system(s)) { + va_space_set_dtb(vs, s->cr[3]); + printf("DTB 0x%016lx has been found from CPU #%zu" + " as system task CR3\n", vs->dtb, i); + return !(va_space_resolve(vs, SharedUserData)); + } + } + + /* + * Thirdly, use KERNEL_GS_BASE from CPU #0 as PRCB address and + * CR3 as [Prcb+0x7000] + */ + if (qe->has_kernel_gs_base) { + QEMUCPUState *s = qe->state[0]; + uint64_t Prcb = s->kernel_gs_base; + uint64_t *cr3 = va_space_resolve(vs, Prcb + 0x7000); + + if (!cr3) { + return 1; + } + + va_space_set_dtb(vs, *cr3); + printf("DirectoryTableBase = 0x%016lx has been found from CPU #0" + " as interrupt handling CR3\n", vs->dtb); + return !(va_space_resolve(vs, SharedUserData)); + } + + return 1; +} + +static int fill_header(WinDumpHeader64 *hdr, struct pa_space *ps, + struct va_space *vs, uint64_t KdDebuggerDataBlock, + KDDEBUGGER_DATA64 *kdbg, uint64_t KdVersionBlock, int nr_cpus) +{ + uint32_t *suite_mask = va_space_resolve(vs, SharedUserData + + KUSD_OFFSET_SUITE_MASK); + int32_t *product_type = va_space_resolve(vs, SharedUserData + + KUSD_OFFSET_PRODUCT_TYPE); + DBGKD_GET_VERSION64 kvb; + WinDumpHeader64 h; + size_t i; + + QEMU_BUILD_BUG_ON(KUSD_OFFSET_SUITE_MASK >= PAGE_SIZE); + QEMU_BUILD_BUG_ON(KUSD_OFFSET_PRODUCT_TYPE >= PAGE_SIZE); + + if (!suite_mask || !product_type) { + return 1; + } + + if (va_space_rw(vs, KdVersionBlock, &kvb, sizeof(kvb), 0)) { + eprintf("Failed to extract KdVersionBlock\n"); + return 1; + } + + h = (WinDumpHeader64) { + .Signature = "PAGE", + .ValidDump = "DU64", + .MajorVersion = kvb.MajorVersion, + .MinorVersion = kvb.MinorVersion, + .DirectoryTableBase = vs->dtb, + .PfnDatabase = kdbg->MmPfnDatabase, + .PsLoadedModuleList = kdbg->PsLoadedModuleList, + .PsActiveProcessHead = kdbg->PsActiveProcessHead, + .MachineImageType = kvb.MachineType, + .NumberProcessors = nr_cpus, + .BugcheckCode = LIVE_SYSTEM_DUMP, + .KdDebuggerDataBlock = KdDebuggerDataBlock, + .DumpType = 1, + .Comment = "Hello from elf2dmp!", + .SuiteMask = *suite_mask, + .ProductType = *product_type, + .SecondaryDataState = kvb.KdSecondaryVersion, + .PhysicalMemoryBlock = (WinDumpPhyMemDesc64) { + .NumberOfRuns = ps->block_nr, + }, + .RequiredDumpSpace = sizeof(h), + }; + + for (i = 0; i < ps->block_nr; i++) { + h.PhysicalMemoryBlock.NumberOfPages += ps->block[i].size / PAGE_SIZE; + h.PhysicalMemoryBlock.Run[i] = (WinDumpPhyMemRun64) { + .BasePage = ps->block[i].paddr / PAGE_SIZE, + .PageCount = ps->block[i].size / PAGE_SIZE, + }; + } + + h.RequiredDumpSpace += h.PhysicalMemoryBlock.NumberOfPages << PAGE_BITS; + + *hdr = h; + + return 0; +} + +static int fill_context(KDDEBUGGER_DATA64 *kdbg, + struct va_space *vs, QEMU_Elf *qe) +{ + int i; + for (i = 0; i < qe->state_nr; i++) { + uint64_t Prcb; + uint64_t Context; + WinContext ctx; + QEMUCPUState *s = qe->state[i]; + + if (va_space_rw(vs, kdbg->KiProcessorBlock + sizeof(Prcb) * i, + &Prcb, sizeof(Prcb), 0)) { + eprintf("Failed to read CPU #%d PRCB location\n", i); + return 1; + } + + if (va_space_rw(vs, Prcb + kdbg->OffsetPrcbContext, + &Context, sizeof(Context), 0)) { + eprintf("Failed to read CPU #%d ContextFrame location\n", i); + return 1; + } + + printf("Filling context for CPU #%d...\n", i); + win_context_init_from_qemu_cpu_state(&ctx, s); + + if (va_space_rw(vs, Context, &ctx, sizeof(ctx), 1)) { + eprintf("Failed to fill CPU #%d context\n", i); + return 1; + } + } + + return 0; +} + +static int write_dump(struct pa_space *ps, + WinDumpHeader64 *hdr, const char *name) +{ + FILE *dmp_file = fopen(name, "wb"); + size_t i; + + if (!dmp_file) { + eprintf("Failed to open output file \'%s\'\n", name); + return 1; + } + + printf("Writing header to file...\n"); + + if (fwrite(hdr, sizeof(*hdr), 1, dmp_file) != 1) { + eprintf("Failed to write dump header\n"); + fclose(dmp_file); + return 1; + } + + for (i = 0; i < ps->block_nr; i++) { + struct pa_block *b = &ps->block[i]; + + printf("Writing block #%zu/%zu to file...\n", i, ps->block_nr); + if (fwrite(b->addr, b->size, 1, dmp_file) != 1) { + eprintf("Failed to write dump header\n"); + fclose(dmp_file); + return 1; + } + } + + return fclose(dmp_file); +} + +static int pe_get_pdb_symstore_hash(uint64_t base, void *start_addr, + char *hash, struct va_space *vs) +{ + const char e_magic[2] = "MZ"; + const char Signature[4] = "PE\0\0"; + const char sign_rsds[4] = "RSDS"; + IMAGE_DOS_HEADER *dos_hdr = start_addr; + IMAGE_NT_HEADERS64 nt_hdrs; + IMAGE_FILE_HEADER *file_hdr = &nt_hdrs.FileHeader; + IMAGE_OPTIONAL_HEADER64 *opt_hdr = &nt_hdrs.OptionalHeader; + IMAGE_DATA_DIRECTORY *data_dir = nt_hdrs.OptionalHeader.DataDirectory; + IMAGE_DEBUG_DIRECTORY debug_dir; + OMFSignatureRSDS rsds; + char *pdb_name; + size_t pdb_name_sz; + size_t i; + + QEMU_BUILD_BUG_ON(sizeof(*dos_hdr) >= PAGE_SIZE); + + if (memcmp(&dos_hdr->e_magic, e_magic, sizeof(e_magic))) { + return 1; + } + + if (va_space_rw(vs, base + dos_hdr->e_lfanew, + &nt_hdrs, sizeof(nt_hdrs), 0)) { + return 1; + } + + if (memcmp(&nt_hdrs.Signature, Signature, sizeof(Signature)) || + file_hdr->Machine != 0x8664 || opt_hdr->Magic != 0x020b) { + return 1; + } + + printf("Debug Directory RVA = 0x%016x\n", + data_dir[IMAGE_FILE_DEBUG_DIRECTORY].VirtualAddress); + + if (va_space_rw(vs, + base + data_dir[IMAGE_FILE_DEBUG_DIRECTORY].VirtualAddress, + &debug_dir, sizeof(debug_dir), 0)) { + return 1; + } + + if (debug_dir.Type != IMAGE_DEBUG_TYPE_CODEVIEW) { + return 1; + } + + if (va_space_rw(vs, + base + debug_dir.AddressOfRawData, + &rsds, sizeof(rsds), 0)) { + return 1; + } + + printf("CodeView signature is \'%.4s\'\n", rsds.Signature); + + if (memcmp(&rsds.Signature, sign_rsds, sizeof(sign_rsds))) { + return 1; + } + + pdb_name_sz = debug_dir.SizeOfData - sizeof(rsds); + pdb_name = malloc(pdb_name_sz); + if (!pdb_name) { + return 1; + } + + if (va_space_rw(vs, base + debug_dir.AddressOfRawData + + offsetof(OMFSignatureRSDS, name), pdb_name, pdb_name_sz, 0)) { + free(pdb_name); + return 1; + } + + printf("PDB name is \'%s\', \'%s\' expected\n", pdb_name, PDB_NAME); + + if (strcmp(pdb_name, PDB_NAME)) { + eprintf("Unexpected PDB name, it seems the kernel isn't found\n"); + free(pdb_name); + return 1; + } + + free(pdb_name); + + sprintf(hash, "%.08x%.04x%.04x%.02x%.02x", rsds.guid.a, rsds.guid.b, + rsds.guid.c, rsds.guid.d[0], rsds.guid.d[1]); + hash += 20; + for (i = 0; i < 6; i++, hash += 2) { + sprintf(hash, "%.02x", rsds.guid.e[i]); + } + + sprintf(hash, "%.01x", rsds.age); + + return 0; +} + +int main(int argc, char *argv[]) +{ + int err = 0; + QEMU_Elf qemu_elf; + struct pa_space ps; + struct va_space vs; + QEMUCPUState *state; + idt_desc_t first_idt_desc; + uint64_t KernBase; + void *nt_start_addr = NULL; + WinDumpHeader64 header; + char pdb_hash[34]; + char pdb_url[] = SYM_URL_BASE PDB_NAME + "/0123456789ABCDEF0123456789ABCDEFx/" PDB_NAME; + struct pdb_reader pdb; + uint64_t KdDebuggerDataBlock; + KDDEBUGGER_DATA64 *kdbg; + uint64_t KdVersionBlock; + + if (argc != 3) { + eprintf("usage:\n\t%s elf_file dmp_file\n", argv[0]); + return 1; + } + + if (QEMU_Elf_init(&qemu_elf, argv[1])) { + eprintf("Failed to initialize QEMU ELF dump\n"); + return 1; + } + + if (pa_space_create(&ps, &qemu_elf)) { + eprintf("Failed to initialize physical address space\n"); + err = 1; + goto out_elf; + } + + state = qemu_elf.state[0]; + printf("CPU #0 CR3 is 0x%016lx\n", state->cr[3]); + + va_space_create(&vs, &ps, state->cr[3]); + if (fix_dtb(&vs, &qemu_elf)) { + eprintf("Failed to find paging base\n"); + err = 1; + goto out_elf; + } + + printf("CPU #0 IDT is at 0x%016lx\n", state->idt.base); + + if (va_space_rw(&vs, state->idt.base, + &first_idt_desc, sizeof(first_idt_desc), 0)) { + eprintf("Failed to get CPU #0 IDT[0]\n"); + err = 1; + goto out_ps; + } + printf("CPU #0 IDT[0] -> 0x%016lx\n", idt_desc_addr(first_idt_desc)); + + KernBase = idt_desc_addr(first_idt_desc) & ~(PAGE_SIZE - 1); + printf("Searching kernel downwards from 0x%16lx...\n", KernBase); + + for (; KernBase >= 0xfffff78000000000; KernBase -= PAGE_SIZE) { + nt_start_addr = va_space_resolve(&vs, KernBase); + if (!nt_start_addr) { + continue; + } + + if (*(uint16_t *)nt_start_addr == 0x5a4d) { /* MZ */ + break; + } + } + + printf("KernBase = 0x%16lx, signature is \'%.2s\'\n", KernBase, + (char *)nt_start_addr); + + if (pe_get_pdb_symstore_hash(KernBase, nt_start_addr, pdb_hash, &vs)) { + eprintf("Failed to get PDB symbol store hash\n"); + err = 1; + goto out_ps; + } + + sprintf(pdb_url, "%s%s/%s/%s", SYM_URL_BASE, PDB_NAME, pdb_hash, PDB_NAME); + printf("PDB URL is %s\n", pdb_url); + + if (download_url(PDB_NAME, pdb_url)) { + eprintf("Failed to download PDB file\n"); + err = 1; + goto out_ps; + } + + if (pdb_init_from_file(PDB_NAME, &pdb)) { + eprintf("Failed to initialize PDB reader\n"); + err = 1; + goto out_pdb_file; + } + + if (!SYM_RESOLVE(KernBase, &pdb, KdDebuggerDataBlock) || + !SYM_RESOLVE(KernBase, &pdb, KdVersionBlock)) { + err = 1; + goto out_pdb; + } + + kdbg = get_kdbg(KernBase, &pdb, &vs, KdDebuggerDataBlock); + if (!kdbg) { + err = 1; + goto out_pdb; + } + + if (fill_header(&header, &ps, &vs, KdDebuggerDataBlock, kdbg, + KdVersionBlock, qemu_elf.state_nr)) { + err = 1; + goto out_pdb; + } + + if (fill_context(kdbg, &vs, &qemu_elf)) { + err = 1; + goto out_pdb; + } + + if (write_dump(&ps, &header, argv[2])) { + eprintf("Failed to save dump\n"); + err = 1; + goto out_kdbg; + } + +out_kdbg: + free(kdbg); +out_pdb: + pdb_exit(&pdb); +out_pdb_file: + unlink(PDB_NAME); +out_ps: + pa_space_destroy(&ps); +out_elf: + QEMU_Elf_exit(&qemu_elf); + + return err; +} |