Ejemplo n.º 1
0
static status_t
init_from_sysmap(vmi_instance_t vmi)
{

    status_t ret = VMI_FAILURE;
    windows_instance_t windows = vmi->os_data;
    dbprint(VMI_DEBUG_MISC, "**Trying to init from sysmap\n");

    reg_t kpcr = 0;
    addr_t kpcr_rva = 0;

    if(vmi->mode != VMI_FILE) {

        if (vmi->page_mode == VMI_PM_IA32E) {
            if (VMI_FAILURE == driver_get_vcpureg(vmi, &kpcr, GS_BASE, 0)) {
                goto done;
            }
        } else if (vmi->page_mode == VMI_PM_LEGACY || vmi->page_mode == VMI_PM_PAE) {
            if (VMI_FAILURE == driver_get_vcpureg(vmi, &kpcr, FS_BASE, 0)) {
                goto done;
            }
        }

        if (VMI_SUCCESS == windows_system_map_symbol_to_address(vmi, "KiInitialPCR", NULL, &kpcr_rva)) {
            // If the sysmap has KiInitialPCR we have Win 7+
            windows->ntoskrnl_va = kpcr - kpcr_rva;
            windows->ntoskrnl = vmi_translate_kv2p(vmi, windows->ntoskrnl_va);
        } else if(kpcr == 0x00000000ffdff000) {
            // If we are in live mode without KiInitialPCR, the KPCR has to be
            // at this VA (XP/Vista) and the KPCR trick [1] is still valid.
            // [1] http://moyix.blogspot.de/2008/04/finding-kernel-global-variables-in.html
            addr_t kdvb = 0, kdvb_offset = 0, kernbase_offset = 0;
            windows_system_map_symbol_to_address(vmi, "_KPCR", "KdVersionBlock", &kdvb_offset);
            windows_system_map_symbol_to_address(vmi, "_DBGKD_GET_VERSION64", "KernBase", &kernbase_offset);
            vmi_read_addr_va(vmi, kpcr+kdvb_offset, 0, &kdvb);
            vmi_read_addr_va(vmi, kdvb+kernbase_offset, 0, &windows->ntoskrnl_va);
            windows->ntoskrnl = vmi_translate_kv2p(vmi, windows->ntoskrnl_va);
        } else {
            goto done;
        }

        dbprint(VMI_DEBUG_MISC, "**KernBase PA=0x%"PRIx64"\n", windows->ntoskrnl);

    }

    // This could happen if we are in file mode or for Win XP
    if (!windows->ntoskrnl) {

        windows->ntoskrnl = get_ntoskrnl_base(vmi, vmi->kpgd);

        // get KdVersionBlock/"_DBGKD_GET_VERSION64"->KernBase
        addr_t kdvb = 0, kernbase_offset = 0;
        windows_system_map_symbol_to_address(vmi, "KdVersionBlock", NULL, &kdvb);
        windows_system_map_symbol_to_address(vmi, "_DBGKD_GET_VERSION64", "KernBase", &kernbase_offset);

        dbprint(VMI_DEBUG_MISC, "**KdVersionBlock RVA 0x%lx. KernBase RVA: 0x%lx\n", kdvb, kernbase_offset);
        dbprint(VMI_DEBUG_MISC, "**KernBase PA=0x%"PRIx64"\n", windows->ntoskrnl);

        if (windows->ntoskrnl && kdvb && kernbase_offset) {
            vmi_read_addr_pa(vmi, windows->ntoskrnl + kdvb + kernbase_offset, &windows->ntoskrnl_va);

            if(!windows->ntoskrnl_va) {
                vmi_read_32_pa(vmi, windows->ntoskrnl + kdvb + kernbase_offset, (uint32_t*)&windows->ntoskrnl_va);
            }

            if(!windows->ntoskrnl_va) {
                dbprint(VMI_DEBUG_MISC, "**failed to find Windows kernel VA via KdVersionBlock\n");
                goto done;
            }
        } else {
            dbprint(VMI_DEBUG_MISC, "**Failed to find required offsets and/or kernel base PA\n");
            goto done;
        }
    }

    dbprint(VMI_DEBUG_MISC, "**KernBase VA=0x%"PRIx64"\n", windows->ntoskrnl_va);

    addr_t ntbuildnumber_rva;
    uint16_t ntbuildnumber = 0;

    // Let's do some sanity checking
    if (VMI_FAILURE == windows_system_map_symbol_to_address(vmi, "NtBuildNumber", NULL, &ntbuildnumber_rva)) {
        goto done;
    }
    if (VMI_FAILURE == vmi_read_16_pa(vmi, windows->ntoskrnl + ntbuildnumber_rva, &ntbuildnumber)) {
        goto done;
    }

    if (ntbuild2version(ntbuildnumber) == VMI_OS_WINDOWS_UNKNOWN) {
        dbprint(VMI_DEBUG_MISC, "Unknown Windows NtBuildNumber: %u. The Rekall Profile may be incorrect for this Windows!\n", ntbuildnumber);
        goto done;
    }

    // The system map seems to be good, lets grab all the required offsets
    if(!windows->pdbase_offset) {
        if (VMI_FAILURE == windows_system_map_symbol_to_address(vmi, "_KPROCESS", "DirectoryTableBase", &windows->pdbase_offset)) {
            goto done;
        }
    }
    if(!windows->tasks_offset) {
        if (VMI_FAILURE == windows_system_map_symbol_to_address(vmi, "_EPROCESS", "ActiveProcessLinks", &windows->tasks_offset)) {
            goto done;
        }
    }
    if(!windows->pid_offset) {
        if (VMI_FAILURE == windows_system_map_symbol_to_address(vmi, "_EPROCESS", "UniqueProcessId", &windows->pid_offset)) {
            goto done;
        }
    }
    if(!windows->pname_offset) {
        if (VMI_FAILURE == windows_system_map_symbol_to_address(vmi, "_EPROCESS", "ImageFileName", &windows->pname_offset)) {
            goto done;
        }
    }

    ret = VMI_SUCCESS;
    dbprint(VMI_DEBUG_MISC, "**init from sysmap success\n");

    done: return ret;

}
Ejemplo n.º 2
0
Archivo: core.c Proyecto: dalevy/libvmi
static status_t
init_from_rekall_profile(vmi_instance_t vmi)
{

    status_t ret = VMI_FAILURE;
    windows_instance_t windows = vmi->os_data;
    dbprint(VMI_DEBUG_MISC, "**Trying to init from Rekall profile\n");

    reg_t kpcr = 0;
    addr_t kpcr_rva = 0;

    // try to find the kernel if we are not connecting to a file and the kernel pa/va were not already specified.
    if(vmi->mode != VMI_FILE && ! ( windows->ntoskrnl && windows->ntoskrnl_va ) ) {

        switch ( vmi->page_mode ) {
            case VMI_PM_IA32E:
                if (VMI_FAILURE == driver_get_vcpureg(vmi, &kpcr, GS_BASE, 0))
                    goto done;
                break;
            case VMI_PM_LEGACY: /* Fall-through */
            case VMI_PM_PAE:
                if (VMI_FAILURE == driver_get_vcpureg(vmi, &kpcr, FS_BASE, 0))
                    goto done;
                break;
            default:
                goto done;
        };

        if (VMI_SUCCESS == rekall_profile_symbol_to_rva(windows->rekall_profile, "KiInitialPCR", NULL, &kpcr_rva)) {
            if ( kpcr <= kpcr_rva || vmi->page_mode == VMI_PM_IA32E && kpcr < 0xffff800000000000 ) {
                dbprint(VMI_DEBUG_MISC, "**vCPU0 doesn't seem to have KiInitialPCR mapped, can't init from Rekall profile.\n");
                goto done;
            }

            // If the Rekall profile has KiInitialPCR we have Win 7+
            windows->ntoskrnl_va = kpcr - kpcr_rva;
            windows->ntoskrnl = vmi_translate_kv2p(vmi, windows->ntoskrnl_va);
        } else if(kpcr == 0x00000000ffdff000) {
            // If we are in live mode without KiInitialPCR, the KPCR has to be
            // at this VA (XP/Vista) and the KPCR trick [1] is still valid.
            // [1] http://moyix.blogspot.de/2008/04/finding-kernel-global-variables-in.html
            addr_t kdvb = 0, kdvb_offset = 0, kernbase_offset = 0;
            rekall_profile_symbol_to_rva(windows->rekall_profile, "_KPCR", "KdVersionBlock", &kdvb_offset);
            rekall_profile_symbol_to_rva(windows->rekall_profile, "_DBGKD_GET_VERSION64", "KernBase", &kernbase_offset);
            vmi_read_addr_va(vmi, kpcr+kdvb_offset, 0, &kdvb);
            vmi_read_addr_va(vmi, kdvb+kernbase_offset, 0, &windows->ntoskrnl_va);
            windows->ntoskrnl = vmi_translate_kv2p(vmi, windows->ntoskrnl_va);
        } else {
            goto done;
        }

        dbprint(VMI_DEBUG_MISC, "**KernBase PA=0x%"PRIx64"\n", windows->ntoskrnl);

        /*
         * If the CR3 value points to a pagetable that hasn't been setup yet
         * we need to resort to finding a valid pagetable the old fashioned way.
         */
        if (windows->ntoskrnl_va && !windows->ntoskrnl)
        {
            windows_find_cr3(vmi);
            windows->ntoskrnl = vmi_translate_kv2p(vmi, windows->ntoskrnl_va);
        }
    }

    // This could happen if we are in file mode or for Win XP
    if (!windows->ntoskrnl) {

        windows->ntoskrnl = get_ntoskrnl_base(vmi, vmi->kpgd);

        // get KdVersionBlock/"_DBGKD_GET_VERSION64"->KernBase
        addr_t kdvb = 0, kernbase_offset = 0;
        rekall_profile_symbol_to_rva(windows->rekall_profile, "KdVersionBlock", NULL, &kdvb);
        rekall_profile_symbol_to_rva(windows->rekall_profile, "_DBGKD_GET_VERSION64", "KernBase", &kernbase_offset);

        dbprint(VMI_DEBUG_MISC, "**KdVersionBlock RVA 0x%lx. KernBase RVA: 0x%lx\n", kdvb, kernbase_offset);
        dbprint(VMI_DEBUG_MISC, "**KernBase PA=0x%"PRIx64"\n", windows->ntoskrnl);

        if (windows->ntoskrnl && kdvb && kernbase_offset) {
            vmi_read_addr_pa(vmi, windows->ntoskrnl + kdvb + kernbase_offset, &windows->ntoskrnl_va);

            if(!windows->ntoskrnl_va) {
                vmi_read_32_pa(vmi, windows->ntoskrnl + kdvb + kernbase_offset, (uint32_t*)&windows->ntoskrnl_va);
            }

            if(!windows->ntoskrnl_va) {
                dbprint(VMI_DEBUG_MISC, "**failed to find Windows kernel VA via KdVersionBlock\n");
                goto done;
            }
        } else {
            dbprint(VMI_DEBUG_MISC, "**Failed to find required offsets and/or kernel base PA\n");
            goto done;
        }
    }

    dbprint(VMI_DEBUG_MISC, "**KernBase VA=0x%"PRIx64"\n", windows->ntoskrnl_va);

    addr_t ntbuildnumber_rva;
    uint16_t ntbuildnumber = 0;

    // Let's do some sanity checking
    if (VMI_FAILURE == rekall_profile_symbol_to_rva(windows->rekall_profile, "NtBuildNumber", NULL, &ntbuildnumber_rva)) {
        goto done;
    }
    if (VMI_FAILURE == vmi_read_16_pa(vmi, windows->ntoskrnl + ntbuildnumber_rva, &ntbuildnumber)) {
        goto done;
    }

    if (ntbuild2version(ntbuildnumber) == VMI_OS_WINDOWS_UNKNOWN) {
        dbprint(VMI_DEBUG_MISC, "Unknown Windows NtBuildNumber: %u, the Rekall Profile may be incorrect for this Windows!\n", ntbuildnumber);
    }

    // The system map seems to be good, lets grab all the required offsets
    if(!windows->pdbase_offset) {
        if (VMI_FAILURE == rekall_profile_symbol_to_rva(windows->rekall_profile, "_KPROCESS", "DirectoryTableBase", &windows->pdbase_offset)) {
            goto done;
        }
    }
    if(!windows->tasks_offset) {
        if (VMI_FAILURE == rekall_profile_symbol_to_rva(windows->rekall_profile, "_EPROCESS", "ActiveProcessLinks", &windows->tasks_offset)) {
            goto done;
        }
    }
    if(!windows->pid_offset) {
        if (VMI_FAILURE == rekall_profile_symbol_to_rva(windows->rekall_profile, "_EPROCESS", "UniqueProcessId", &windows->pid_offset)) {
            goto done;
        }
    }
    if(!windows->pname_offset) {
        if (VMI_FAILURE == rekall_profile_symbol_to_rva(windows->rekall_profile, "_EPROCESS", "ImageFileName", &windows->pname_offset)) {
            goto done;
        }
    }

    ret = VMI_SUCCESS;
    dbprint(VMI_DEBUG_MISC, "**init from Rekall profile success\n");

    done: return ret;

}
Ejemplo n.º 3
0
Archivo: kdbg.c Proyecto: bentau/libvmi
/*
 * This functions is responsible for setting up
 * Windows specific variables:
 *  - ntoskrnl (*)
 *  - ntoskrnl_va (*)
 *  - kdbg_offset (*)
 *  - kdbg_va (*)
 * The variables marked with (*) can be also specified
 * in the libvmi config.
 */
status_t
init_from_kdbg(
    vmi_instance_t vmi)
{
    status_t ret = VMI_FAILURE;
    addr_t kernbase_pa = 0;
    addr_t kernbase_va = 0;
    addr_t kdbg_pa = 0;

    if (vmi->os_data == NULL) {
        goto exit;
    }

    windows_instance_t windows = vmi->os_data;

    /* If all 3 values are specified in the config, we can calculate ntoskrnl_va,
     * but can't verify if there is no arch for doing translations.
     */
    if (windows->kdbg_va && windows->kdbg_offset && windows->ntoskrnl
            && !vmi->arch_interface) {
        /* All values were user specified, so set them, but we can't use
         * translations to verify them */
        windows->ntoskrnl_va = windows->kdbg_va - windows->kdbg_offset;
        goto done;
    }

    if (!vmi->arch_interface) {
        /* nothing that requires a virtual-to-physical translation will work
         * so skip straight to the physical only methods. */
        goto find_kdbg;
    }

    /* Otherwise, look up what we need and check for consistency */

    if (windows->kdbg_va) {
        dbprint(VMI_DEBUG_MISC, "**using KdDebuggerDataBlock address=0x%"PRIx64" from config\n",
                windows->kdbg_va);

        if (VMI_SUCCESS != windows_kdbg_lookup(vmi, "KernBase", &windows->ntoskrnl_va)) {
            dbprint(VMI_DEBUG_MISC, "**Error reading KernBase value, falling back to search methods\n");
            goto find_kdbg;
        }

        dbprint(VMI_DEBUG_MISC, "**KernBase VA=0x%"PRIx64"\n", windows->ntoskrnl_va);

        if (windows->kdbg_offset) {
            /* only needed ntoskrnl_va, verify the other values */
            if (windows->kdbg_va != (windows->ntoskrnl_va + windows->kdbg_offset)) {
                errprint("Invalid configuration values for win_kdvb and win_kdbg\n");
                goto exit;
            }

        } else {
            windows->kdbg_offset = windows->kdbg_va - windows->ntoskrnl_va;
        }
    } else if (windows->ntoskrnl && windows->kdbg_offset) {
        /* Calculate ntoskrnl_va and kdbg_va */
        unsigned long offset = 0;
        kdbg_symbol_offset("KernBase", &offset);
        if (VMI_FAILURE == vmi_read_addr_pa(vmi, windows->ntoskrnl + windows->kdbg_offset + offset, &windows->ntoskrnl_va)) {
            errprint("Inconsistent addresses passed in the config!\n");
            goto exit;
        }

        dbprint(VMI_DEBUG_MISC, "**KernBase VA=0x%"PRIx64"\n", windows->ntoskrnl_va);

        windows->kdbg_va = windows->ntoskrnl_va - windows->kdbg_offset;
        dbprint(VMI_DEBUG_MISC, "**set KdDebuggerDataBlock address=0x%"PRIx64"\n",
                windows->kdbg_va);
    } else {
        /* only ntoskrnl or kdbg_offset were given, which are not
         * enough to find and calculate the others, so fall back to search methods. */
        goto find_kdbg;
    }

    addr_t test = 0;

    if (!windows->ntoskrnl) {
        if ( VMI_FAILURE == vmi_translate_kv2p(vmi, windows->ntoskrnl_va, &windows->ntoskrnl) )
            goto find_kdbg;

        dbprint(VMI_DEBUG_MISC, "**set KernBase PA=0x%"PRIx64"\n", windows->ntoskrnl);
    } else if (VMI_FAILURE == vmi_translate_kv2p(vmi, windows->ntoskrnl_va, &test) || test != windows->ntoskrnl) {
        errprint("Invalid configuration values, win_ntoskrnl not match translated KernBase physical address\n");
        goto exit;
    }

    goto done;

    // We don't have the standard config informations
    // so lets try our kdbg search method
find_kdbg:
    dbprint(VMI_DEBUG_MISC, "**Attempting KdDebuggerDataBlock search methods\n");

    if (VMI_SUCCESS == find_kdbg_address_instant(vmi, &kdbg_pa, &kernbase_pa, &kernbase_va)) {
        goto found;
    }
    if (VMI_SUCCESS == find_kdbg_address_faster(vmi, &kdbg_pa, &kernbase_pa, &kernbase_va)) {
        goto found;
    }
    if (VMI_SUCCESS == find_kdbg_address_fast(vmi, &kdbg_pa, &kernbase_pa, &kernbase_va)) {
        goto found;
    }

    /* NOTE: This is the only method that does anything for VMI_FILE */
    if (VMI_SUCCESS == find_kdbg_address(vmi, &kdbg_pa, &kernbase_va)) {
        kernbase_pa = get_ntoskrnl_base(vmi, 0);
        goto found;
    }

    dbprint(VMI_DEBUG_MISC, "**All KdDebuggerDataBlock search methods failed\n");
    goto exit;

found:
    windows->ntoskrnl_va = kernbase_va;
    dbprint(VMI_DEBUG_MISC, "**set KernBase VA=0x%"PRIx64"\n", windows->ntoskrnl_va);

    if (!windows->ntoskrnl) {
        windows->ntoskrnl = kernbase_pa;
        printf("LibVMI Suggestion: set win_ntoskrnl=0x%"PRIx64" in libvmi.conf for faster startup.\n",
               windows->ntoskrnl);
    } else if (windows->ntoskrnl != kernbase_pa) {
        errprint("LibVMI found physical kernel base address 0x%"PRIx64" that conflicts with provided value from config file!\n",
                 kernbase_pa);
        goto exit;
    }

    if (!windows->kdbg_offset) {
        windows->kdbg_offset = kdbg_pa - windows->ntoskrnl;
        printf("LibVMI Suggestion: set win_kdbg=0x%"PRIx64" in libvmi.conf for faster startup.\n",
               windows->kdbg_offset);
    } else if (windows->kdbg_offset != kdbg_pa - kernbase_pa) {
        errprint("LibVMI found win_kdbg offset 0x%"PRIx64" that conflicts with provided value from config file!\n",
                 kdbg_pa - kernbase_pa);
        goto exit;
    }

    if (!windows->kdbg_va) {
        windows->kdbg_va = windows->ntoskrnl_va + windows->kdbg_offset;
        printf("LibVMI Suggestion: set win_kdvb=0x%"PRIx64" in libvmi.conf for faster startup.\n",
               windows->kdbg_va);
    } else if (windows->kdbg_va != windows->ntoskrnl_va + windows->kdbg_offset) {
        errprint("LibVMI found win_kdvb offset 0x%"PRIx64" that conflicts with provided value from config file!\n",
                 windows->ntoskrnl_va + windows->kdbg_offset);
        goto exit;
    }

done:
    if (!kdbg_pa) {
        kdbg_pa = windows->ntoskrnl + windows->kdbg_offset;
    }
    windows->version = find_windows_version(vmi, kdbg_pa);
    if (VMI_OS_WINDOWS_UNKNOWN == windows->version) {
        errprint("Unsupported Windows version or incorrect configuration\n");
    }

    ret = VMI_SUCCESS;
exit:
    return ret;
}