Allows other modules to use the same logic for uploading files. Signed-off-by: Matteo Cafasso <noxdafox(a)gmail.com&gt; --- daemon/daemon.h | 3 +++ daemon/upload.c | 70 ++++++++++++++++++++++++++++++++------------------------- 2 files changed, 42 insertions(+), 31 deletions(-) diff --git a/daemon/daemon.h b/daemon/daemon.h index 793074dea..bc89f78dd 100644 --- a/daemon/daemon.h +++ b/daemon/daemon.h @@ -258,6 +258,9 @@ extern int64_t ntfs_minimum_size (const char *device); extern int swap_set_uuid (const char *device, const char *uuid); extern int swap_set_label (const char *device, const char *label); +/*-- in upload.c --*/ +extern int upload_to_fd (int fd); + /* ordinary daemon functions use these to indicate errors * NB: you don't need to prefix the string with the current command, * it is added automatically by the client-side RPC stubs. diff --git a/daemon/upload.c b/daemon/upload.c index 655baf29d..144bb246c 100644 --- a/daemon/upload.c +++ b/daemon/upload.c @@ -54,60 +54,68 @@ write_cb (void *data_vp, const void *buf, size_t len) return 0; } +int +upload_to_fd (int fd) +{ + int ret = 0, err = 0; + struct write_cb_data data = { .fd = fd, .written = 0 }; + + ret = receive_file (write_cb, &data); + if (ret == -1) { /* write error */ + err = errno; + ret = cancel_receive (); + errno = err; + reply_with_error ("write error"); + close (fd); + return -1; + } + if (ret == -2) { /* cancellation from library */ + /* This error is ignored by the library since it initiated the + * cancel. Nevertheless we must send an error reply here. + */ + reply_with_error ("file upload cancelled"); + close (fd); + return -1; + } + + if (close (fd) == -1) { + reply_with_perror ("close"); + return -1; + } + + return 0; +} + /* Has one FileIn parameter. */ static int upload (const char *filename, int flags, int64_t offset) { - struct write_cb_data data = { .written = 0 }; - int err, r, is_dev; + int err, is_dev, fd; is_dev = STRPREFIX (filename, "/dev/"); if (!is_dev) CHROOT_IN; - data.fd = open (filename, flags, 0666); + fd = open (filename, flags, 0666); if (!is_dev) CHROOT_OUT; - if (data.fd == -1) { + if (fd == -1) { err = errno; - r = cancel_receive (); + cancel_receive (); errno = err; reply_with_perror ("%s", filename); return -1; } if (offset) { - if (lseek (data.fd, offset, SEEK_SET) == -1) { + if (lseek (fd, offset, SEEK_SET) == -1) { err = errno; - r = cancel_receive (); + cancel_receive (); errno = err; reply_with_perror ("lseek: %s", filename); return -1; } } - r = receive_file (write_cb, &data); - if (r == -1) { /* write error */ - err = errno; - r = cancel_receive (); - errno = err; - reply_with_error ("write error: %s", filename); - close (data.fd); - return -1; - } - if (r == -2) { /* cancellation from library */ - /* This error is ignored by the library since it initiated the - * cancel. Nevertheless we must send an error reply here. - */ - reply_with_error ("file upload cancelled"); - close (data.fd); - return -1; - } - - if (close (data.fd) == -1) { - reply_with_perror ("close: %s", filename); - return -1; - } - - return 0; + return upload_to_fd (fd); } /* Has one FileIn parameter. */ -- 2.11.0

The yara_load API allows to load a set of Yara rules contained within a file on the host. Rules can be in binary format, as when compiled with yarac command, or in source code format. In the latter case, the rules will be first compiled and then loaded. Subsequent calls of the yara_load API will result in the discard of the previously loaded rules. Signed-off-by: Matteo Cafasso <noxdafox(a)gmail.com&gt; --- daemon/Makefile.am | 1 + daemon/cleanups.c | 9 +++ daemon/cleanups.h | 2 + daemon/yara.c | 201 ++++++++++++++++++++++++++++++++++++++++++++++++++ generator/Makefile.am | 3 + generator/actions.ml | 3 +- generator/proc_nr.ml | 1 + gobject/Makefile.inc | 6 +- lib/MAX_PROC_NR | 2 +- 9 files changed, 224 insertions(+), 4 deletions(-) create mode 100644 daemon/yara.c diff --git a/daemon/Makefile.am b/daemon/Makefile.am index 9d73bb805..563622cdb 100644 --- a/daemon/Makefile.am +++ b/daemon/Makefile.am @@ -164,6 +164,7 @@ guestfsd_SOURCES = \ wc.c \ xattr.c \ xfs.c \ + yara.c \ zero.c \ zerofree.c diff --git a/daemon/cleanups.c b/daemon/cleanups.c index 092e493d7..3102cf94b 100644 --- a/daemon/cleanups.c +++ b/daemon/cleanups.c @@ -62,6 +62,15 @@ cleanup_close (void *ptr) } void +cleanup_fclose (void *ptr) +{ + FILE *f = * (FILE **) ptr; + + if (f) + fclose (f); +} + +void cleanup_aug_close (void *ptr) { augeas *aug = * (augeas **) ptr; diff --git a/daemon/cleanups.h b/daemon/cleanups.h index 6746e2744..a791244cb 100644 --- a/daemon/cleanups.h +++ b/daemon/cleanups.h @@ -26,6 +26,7 @@ extern void cleanup_free (void *ptr); extern void cleanup_free_string_list (void *ptr); extern void cleanup_unlink_free (void *ptr); extern void cleanup_close (void *ptr); +extern void cleanup_fclose (void *ptr); extern void cleanup_aug_close (void *ptr); extern void cleanup_free_stringsbuf (void *ptr); @@ -35,6 +36,7 @@ extern void cleanup_free_stringsbuf (void *ptr); __attribute__((cleanup(cleanup_free_string_list))) #define CLEANUP_UNLINK_FREE __attribute__((cleanup(cleanup_unlink_free))) #define CLEANUP_CLOSE __attribute__((cleanup(cleanup_close))) +#define CLEANUP_FCLOSE __attribute__((cleanup(cleanup_fclose))) #define CLEANUP_AUG_CLOSE __attribute__((cleanup(cleanup_aug_close))) #define CLEANUP_FREE_STRINGSBUF __attribute__((cleanup(cleanup_free_stringsbuf))) #else diff --git a/daemon/yara.c b/daemon/yara.c new file mode 100644 index 000000000..0e4128aed --- /dev/null +++ b/daemon/yara.c @@ -0,0 +1,201 @@ +/* libguestfs - the guestfsd daemon + * Copyright (C) 2016 Red Hat Inc. + * + * 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. + */ + +#include <config.h> + +#include <stdio.h> +#include <fcntl.h> +#include <stdlib.h> +#include <inttypes.h> +#include <string.h> +#include <unistd.h> +#include <stdbool.h> +#include <rpc/xdr.h> +#include <rpc/types.h> +#include <sys/types.h> +#include <sys/stat.h> + +#include "daemon.h" +#include "actions.h" +#include "optgroups.h" +#include "guestfs_protocol.h" + +#ifdef HAVE_YARA + +#include <yara.h> + +#define CLEANUP_DESTROY_YARA_COMPILER \ + __attribute__((cleanup(cleanup_destroy_yara_compiler))) + +struct write_callback_data { + int fd; + uint64_t written; +}; + +/* Yara compiled rules. */ +static YR_RULES *rules = NULL; +static bool initialized = false; + +static int compile_rules_file (const char *, const char *); +static void compile_error_callback (int, const char *, int, const char *, void *); +static void cleanup_destroy_yara_compiler (void *ptr); + +/* Has one FileIn parameter. + * Takes optional arguments, consult optargs_bitmask. + */ +int +do_yara_load (const char *namespace) +{ + int ret = 0; + CLEANUP_CLOSE int fd = -1; + char tmpfile[] = "/tmp/yaraXXXXXX"; + + fd = mkstemp (tmpfile); + if (fd == -1) { + reply_with_perror ("mkstemp"); + return -1; + } + + ret = upload_to_fd (fd); + if (ret < 0) { + unlink (tmpfile); + return -1; + } + + /* Initialize yara only once. */ + if (!initialized) { + ret = yr_initialize (); + if (ret != ERROR_SUCCESS) { + reply_with_error ("failed initializing yara"); + unlink (tmpfile); + return -1; + } + + initialized = true; + } + + /* Clear namespace if no optional parameter is given. */ + if (!(optargs_bitmask & GUESTFS_YARA_LOAD_NAMESPACE_BITMASK)) + namespace = NULL; + + /* Try to load the rules as compiled. + * If their are in source code format, compile them first. + */ + ret = yr_rules_load (tmpfile, &rules); + if (ret == ERROR_INVALID_FILE) + ret = compile_rules_file (tmpfile, namespace); + + unlink (tmpfile); + + return (ret == ERROR_SUCCESS) ? 0 : -1; +} + +/* Compile source code rules and load them. + * Return ERROR_SUCCESS on success, Yara error code type on error. + */ +static int +compile_rules_file (const char *rules_path, const char *namespace) +{ + int ret = 0; + CLEANUP_FCLOSE FILE *rule_file = NULL; + CLEANUP_DESTROY_YARA_COMPILER YR_COMPILER *compiler = NULL; + + ret = yr_compiler_create (&compiler); + if (ret != ERROR_SUCCESS) { + reply_with_error ("yr_compiler_create"); + return ret; + } + + yr_compiler_set_callback (compiler, compile_error_callback, NULL); + + rule_file = fopen (rules_path, "r"); + if (rule_file == NULL) { + reply_with_error ("unable to open rules file"); + return ret; + } + + ret = yr_compiler_add_file (compiler, rule_file, namespace, NULL); + if (ret > 0) + return ret; + + ret = yr_compiler_get_rules (compiler, &rules); + if (ret == ERROR_INSUFICIENT_MEMORY) { + errno = ENOMEM; + reply_with_perror ("yr_compiler_get_rules"); + } + + return ret; +} + +/* Yara compilation error callback. + * Reports back the compilation error message. + * Prints compilation warnings if verbose. + */ +static void +compile_error_callback(int level, const char *name, int line, + const char *message, void *data) +{ + if (level == YARA_ERROR_LEVEL_ERROR) + reply_with_error ("Yara error (line %d): %s", line, message); + else if (verbose) + fprintf (stderr, "Yara warning (line %d): %s\n", line, message); +} + +/* Clean up yara handle on daemon exit. */ +void yara_finalize (void) __attribute__((destructor)); + +void +yara_finalize (void) +{ + int ret = 0; + + if (!initialized) + return; + + if (rules != NULL) { + yr_rules_destroy (rules); + rules = NULL; + } + + ret = yr_finalize (); + if (ret != ERROR_SUCCESS) + perror ("yr_finalize"); + + initialized = false; +} + +static void +cleanup_destroy_yara_compiler (void *ptr) +{ + YR_COMPILER *compiler = * (YR_COMPILER **) ptr; + + if (compiler != NULL) + yr_compiler_destroy (compiler); +} + +int +optgroup_libyara_available (void) +{ + return 1; +} + +#else /* !HAVE_YARA */ + +OPTGROUP_YARA_NOT_AVAILABLE + +#endif /* !HAVE_YARA */ diff --git a/generator/Makefile.am b/generator/Makefile.am index cb69fe831..0f7fc289b 100644 --- a/generator/Makefile.am +++ b/generator/Makefile.am @@ -43,6 +43,8 @@ sources = \ actions_properties_deprecated.mli \ actions_tsk.ml \ actions_tsk.mli \ + actions_yara.ml \ + actions_yara.mli \ bindtests.ml \ bindtests.mli \ c.ml \ @@ -130,6 +132,7 @@ objects = \ actions_properties.cmo \ actions_properties_deprecated.cmo \ actions_tsk.cmo \ + actions_yara.cmo \ actions.cmo \ structs.cmo \ fish_commands.cmo \ diff --git a/generator/actions.ml b/generator/actions.ml index fa0e6568a..4df3b2a32 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -50,7 +50,8 @@ let daemon_functions = Actions_core_deprecated.daemon_functions @ Actions_debug.daemon_functions @ Actions_hivex.daemon_functions @ - Actions_tsk.daemon_functions + Actions_tsk.daemon_functions @ + Actions_yara.daemon_functions (* Some post-processing of the basic lists of actions. *) diff --git a/generator/proc_nr.ml b/generator/proc_nr.ml index b3be31996..d50cc9efa 100644 --- a/generator/proc_nr.ml +++ b/generator/proc_nr.ml @@ -479,6 +479,7 @@ let proc_nr = [ 469, "aug_transform"; 470, "internal_find_inode"; 471, "mksquashfs"; +472, "yara_load"; ] (* End of list. If adding a new entry, add it at the end of the list diff --git a/gobject/Makefile.inc b/gobject/Makefile.inc index 8fa8599d3..b0ebf15d9 100644 --- a/gobject/Makefile.inc +++ b/gobject/Makefile.inc @@ -111,7 +111,8 @@ guestfs_gobject_headers= \ include/guestfs-gobject/optargs-umount_local.h \ include/guestfs-gobject/optargs-xfs_admin.h \ include/guestfs-gobject/optargs-xfs_growfs.h \ - include/guestfs-gobject/optargs-xfs_repair.h + include/guestfs-gobject/optargs-xfs_repair.h \ + include/guestfs-gobject/optargs-yara_load.h guestfs_gobject_sources= \ src/session.c \ @@ -203,4 +204,5 @@ guestfs_gobject_sources= \ src/optargs-umount_local.c \ src/optargs-xfs_admin.c \ src/optargs-xfs_growfs.c \ - src/optargs-xfs_repair.c + src/optargs-xfs_repair.c \ + src/optargs-yara_load.c diff --git a/lib/MAX_PROC_NR b/lib/MAX_PROC_NR index c305aa5ae..68cfb10d1 100644 --- a/lib/MAX_PROC_NR +++ b/lib/MAX_PROC_NR @@ -1 +1 @@ -471 +472 -- 2.11.0

The yara_destroy API allows to claim resources back via the removal of the previously loaded Yara rules. Signed-off-by: Matteo Cafasso <noxdafox(a)gmail.com&gt; --- daemon/yara.c | 14 ++++++++++++++ generator/proc_nr.ml | 1 + lib/MAX_PROC_NR | 2 +- 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/daemon/yara.c b/daemon/yara.c index 0e4128aed..cb49593c7 100644 --- a/daemon/yara.c +++ b/daemon/yara.c @@ -105,6 +105,20 @@ do_yara_load (const char *namespace) return (ret == ERROR_SUCCESS) ? 0 : -1; } +int +do_yara_destroy (void) +{ + if (rules == NULL) { + reply_with_error ("no yara rules loaded"); + return -1; + } + + yr_rules_destroy (rules); + rules = NULL; + + return 0; +} + /* Compile source code rules and load them. * Return ERROR_SUCCESS on success, Yara error code type on error. */ diff --git a/generator/proc_nr.ml b/generator/proc_nr.ml index d50cc9efa..d471b1a83 100644 --- a/generator/proc_nr.ml +++ b/generator/proc_nr.ml @@ -480,6 +480,7 @@ let proc_nr = [ 470, "internal_find_inode"; 471, "mksquashfs"; 472, "yara_load"; +473, "yara_destroy"; ] (* End of list. If adding a new entry, add it at the end of the list diff --git a/lib/MAX_PROC_NR b/lib/MAX_PROC_NR index 68cfb10d1..8410b8b89 100644 --- a/lib/MAX_PROC_NR +++ b/lib/MAX_PROC_NR @@ -1 +1 @@ -472 +473 -- 2.11.0

The yara_scan API parses the file generated by the daemon counterpart function and returns the list of yara_detection structs to the user. It writes the daemon's command output on a temporary file and parses it, deserialising the XDR formatted yara_detection structs. It returns to the caller the list of yara_detection structs generated by the internal_yara_scan command. Signed-off-by: Matteo Cafasso <noxdafox(a)gmail.com&gt; --- generator/actions.ml | 3 +- lib/Makefile.am | 1 + lib/yara.c | 127 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+), 1 deletion(-) create mode 100644 lib/yara.c diff --git a/generator/actions.ml b/generator/actions.ml index 4df3b2a32..d36a4f8a9 100644 --- a/generator/actions.ml +++ b/generator/actions.ml @@ -38,7 +38,8 @@ let non_daemon_functions = Actions_inspection_deprecated.non_daemon_functions @ Actions_properties.non_daemon_functions @ Actions_properties_deprecated.non_daemon_functions @ - Actions_tsk.non_daemon_functions + Actions_tsk.non_daemon_functions @ + Actions_yara.non_daemon_functions (* daemon_functions are any functions which cause some action * to take place in the daemon. diff --git a/lib/Makefile.am b/lib/Makefile.am index 063706f8f..fc55c2dcf 100644 --- a/lib/Makefile.am +++ b/lib/Makefile.am @@ -127,6 +127,7 @@ libguestfs_la_SOURCES = \ wait.c \ whole-file.c \ version.c \ + yara.c \ libguestfs.syms libguestfs_la_CPPFLAGS = \ diff --git a/lib/yara.c b/lib/yara.c new file mode 100644 index 000000000..864766e7a --- /dev/null +++ b/lib/yara.c @@ -0,0 +1,127 @@ +/* libguestfs + * Copyright (C) 2016 Red Hat Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <fcntl.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <string.h> +#include <rpc/xdr.h> +#include <rpc/types.h> + +#include "guestfs.h" +#include "guestfs_protocol.h" +#include "guestfs-internal.h" +#include "guestfs-internal-all.h" +#include "guestfs-internal-actions.h" + +static struct guestfs_yara_detection_list *parse_yara_detection_file (guestfs_h *, const char *); +static int deserialise_yara_detection_list (guestfs_h *, FILE *, struct guestfs_yara_detection_list *); + +struct guestfs_yara_detection_list * +guestfs_impl_yara_scan (guestfs_h *g, const char *path) +{ + int ret = 0; + CLEANUP_UNLINK_FREE char *tmpfile = NULL; + + tmpfile = guestfs_int_make_temp_path (g, "yara_scan"); + if (tmpfile == NULL) + return NULL; + + ret = guestfs_internal_yara_scan (g, path, tmpfile); + if (ret < 0) + return NULL; + + return parse_yara_detection_file (g, tmpfile); /* caller frees */ +} + +/* Parse the file content and return detections list. + * Return a list of yara_detection on success, NULL on error. + */ +static struct guestfs_yara_detection_list * +parse_yara_detection_file (guestfs_h *g, const char *tmpfile) +{ + int ret = 0; + CLEANUP_FCLOSE FILE *fp = NULL; + struct guestfs_yara_detection_list *detections = NULL; + + fp = fopen (tmpfile, "r"); + if (fp == NULL) { + perrorf (g, "fopen: %s", tmpfile); + return NULL; + } + + /* Initialise results array. */ + detections = safe_malloc (g, sizeof (*detections)); + detections->len = 8; + detections->val = safe_malloc (g, detections->len * + sizeof (*detections->val)); + + /* Deserialise buffer into detection list. */ + ret = deserialise_yara_detection_list (g, fp, detections); + if (ret < 0) { + guestfs_free_yara_detection_list (detections); + return NULL; + } + + return detections; +} + +/* Deserialise the file content and populate the detection list. + * Return the number of deserialised detections, -1 on error. + */ +static int +deserialise_yara_detection_list (guestfs_h *g, FILE *fp, + struct guestfs_yara_detection_list *detections) +{ + XDR xdr; + int ret = 0; + uint32_t index = 0; + struct stat statbuf; + + ret = fstat (fileno(fp), &statbuf); + if (ret == -1) + return -1; + + xdrstdio_create (&xdr, fp, XDR_DECODE); + + for (index = 0; xdr_getpos (&xdr) < statbuf.st_size; index++) { + if (index == detections->len) { + detections->len = 2 * detections->len; + detections->val = safe_realloc (g, detections->val, + detections->len * + sizeof (*detections->val)); + } + + /* Clear the entry so xdr logic will allocate necessary memory. */ + memset (&detections->val[index], 0, sizeof (*detections->val)); + ret = xdr_guestfs_int_yara_detection (&xdr, (guestfs_int_yara_detection *) + &detections->val[index]); + if (ret == 0) + break; + } + + xdr_destroy (&xdr); + detections->len = index; + + return ret ? 0 : -1; +} -- 2.11.0