This change introduces new filtering architecture primitives: filter,
filter_action and bool_expression. It also changes processing of -e
strace option. Now, filtering is done after decoding of syscall and
tcp->qual_flg stores filtering results.
* basic_actions.c: New file.
* basic_filters.c: Rename functions, add new filters' functions.
* defs.h (struct tcb): Change inject options variable.
(QUAL_READ, QUAL_WRITE): Change description.
(read_set, write_set): Remove global set variables.
(is_number_in_set): Change declaration.
(qualify, qual_flags): Remove old declarations ...
(filter_syscall, parse_qualify_filter,
sort_filter_actions): ... and add new declarations.
* filter.c: New file.
* filter.h: Change declarations.
* filter_action.c: New file.
* filter_expression.c: Likewise.
* filter_qualify.c: Generate new filters.
* Makefile.am (strace_SOURCES): Add new files.
* strace.c (droptcb): Remove inject_vec freeing.
(init): Change qualify to parse_qualify_filter.
Add sorting of filter actions.
(trace_syscall): Add filtering after syscall decoding.
* syscall.c (decode_socket_subcall): Remove qual_flags from decoder.
(decode_ipc_subcall): Likewise.
(decode_mips_subcall): Likewise.
(get_scno): Likewise.
(inject_vec, tcb_inject_opts, tamper_with_syscall_entering,
tamper_with_syscall_exiting): Remove inject_vec support code.
(dumpio): Check tcp->qual_flg instead of global set.
---
Makefile.am | 4 ++
basic_actions.c | 98 +++++++++++++++++++++++++
basic_filters.c | 107 ++++++++++++++++++++-------
defs.h | 15 ++--
filter.c | 147 +++++++++++++++++++++++++++++++++++++
filter.h | 36 ++++++++--
filter_action.c | 203 ++++++++++++++++++++++++++++++++++++++++++++++++++++
filter_expression.c | 131 +++++++++++++++++++++++++++++++++
filter_qualify.c | 135 +++++++++++++++++-----------------
strace.c | 20 +++---
syscall.c | 31 ++------
11 files changed, 783 insertions(+), 144 deletions(-)
create mode 100644 basic_actions.c
create mode 100644 filter.c
create mode 100644 filter_action.c
create mode 100644 filter_expression.c
diff --git a/Makefile.am b/Makefile.am
index 4f5ebfb..7299141 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -86,6 +86,7 @@ strace_SOURCES = \
affinity.c \
aio.c \
alpha.c \
+ basic_actions.c \
basic_filters.c \
bjm.c \
block.c \
@@ -125,7 +126,10 @@ strace_SOURCES = \
fetch_struct_statfs.c \
file_handle.c \
file_ioctl.c \
+ filter_action.c \
+ filter_expression.c \
filter_qualify.c \
+ filter.c \
filter.h \
fs_x_ioctl.c \
flock.c \
diff --git a/basic_actions.c b/basic_actions.c
new file mode 100644
index 0000000..de87cde
--- /dev/null
+++ b/basic_actions.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2017 Nikolay Marchuk <marchuk.nikola...@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "defs.h"
+
+bool
+is_traced(struct tcb *tcp)
+{
+ return (tcp->qual_flg & QUAL_TRACE);
+}
+
+void *
+parse_null(const char *str)
+{
+ return NULL;
+}
+
+void
+free_null(void *_priv_data)
+{
+ return;
+}
+
+void
+apply_trace(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_TRACE;
+}
+void
+apply_inject(struct tcb *tcp, void *_priv_data)
+{
+ struct inject_opts **inject_vec = (struct inject_opts **)_priv_data;
+ tcp->qual_flg |= QUAL_INJECT;
+ tcp->inject_opts = (scno_in_range(tcp->scno) &&
inject_vec[current_personality])
+ ? &inject_vec[current_personality][tcp->scno] : NULL;
+}
+void*
+parse_inject(const char *str)
+{
+ return NULL;
+}
+void free_inject(void *_priv_data)
+{
+ struct inject_opts **vec = (struct inject_opts **)_priv_data;
+ unsigned int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p)
+ if (vec[p])
+ free(vec[p]);
+ free(vec);
+}
+void
+apply_read(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_READ;
+}
+void
+apply_write(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_WRITE;
+}
+void
+apply_raw(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_RAW;
+}
+void
+apply_abbrev(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_ABBREV;
+}
+void
+apply_verbose(struct tcb *tcp, void *_priv_data)
+{
+ tcp->qual_flg |= QUAL_VERBOSE;
+}
diff --git a/basic_filters.c b/basic_filters.c
index 316b733..d0816a4 100644
--- a/basic_filters.c
+++ b/basic_filters.c
@@ -25,10 +25,8 @@
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
-
#include "defs.h"
#include <regex.h>
-#include "filter.h"
typedef unsigned int number_slot_t;
#define BITS_PER_SLOT (sizeof(number_slot_t) * 8)
@@ -39,6 +37,12 @@ struct number_set {
bool not;
};
+bool
+is_empty(struct number_set *set)
+{
+ return !(set->nslots || set->not);
+}
+
static void
number_setbit(const unsigned int i, number_slot_t *const vec)
{
@@ -48,9 +52,11 @@ number_setbit(const unsigned int i, number_slot_t *const vec)
static bool
number_isset(const unsigned int i, const number_slot_t *const vec)
{
- return vec[i / BITS_PER_SLOT] & ((number_slot_t) 1 << (i %
BITS_PER_SLOT));
+ return (vec[i / BITS_PER_SLOT]
+ & ((number_slot_t) 1 << (i % BITS_PER_SLOT))) ? true : false;
}
+
static void
reallocate_number_set(struct number_set *const set, const unsigned int
new_nslots)
{
@@ -62,7 +68,7 @@ reallocate_number_set(struct number_set *const set, const
unsigned int new_nslot
set->nslots = new_nslots;
}
-void
+static void
add_number_to_set(const unsigned int number, struct number_set *const set)
{
reallocate_number_set(set, number / BITS_PER_SLOT + 1);
@@ -77,7 +83,7 @@ is_number_in_set(const unsigned int number, const struct
number_set *const set)
}
static bool
-qualify_syscall_number(const char *s, struct number_set *set)
+parse_syscall_number(const char *s, struct number_set *set)
{
int n = string_to_uint(s);
if (n < 0)
@@ -108,7 +114,7 @@ regerror_msg_and_die(int errcode, const regex_t *preg,
}
static bool
-qualify_syscall_regex(const char *s, struct number_set *set)
+parse_syscall_regex(const char *s, struct number_set *set)
{
regex_t preg;
int rc;
@@ -180,7 +186,7 @@ lookup_class(const char *s)
}
static bool
-qualify_syscall_class(const char *s, struct number_set *set)
+parse_syscall_class(const char *s, struct number_set *set)
{
const unsigned int n = lookup_class(s);
if (!n)
@@ -203,7 +209,7 @@ qualify_syscall_class(const char *s, struct number_set *set)
}
static bool
-qualify_syscall_name(const char *s, struct number_set *set)
+parse_syscall_name(const char *s, struct number_set *set)
{
unsigned int p;
bool found = false;
@@ -224,8 +230,9 @@ qualify_syscall_name(const char *s, struct number_set *set)
return found;
}
+
static bool
-qualify_syscall(const char *token, struct number_set *set)
+parse_syscall(const char *token, struct number_set *set)
{
bool ignore_fail = false;
@@ -234,21 +241,17 @@ qualify_syscall(const char *token, struct number_set *set)
ignore_fail = true;
}
if (*token >= '0' && *token <= '9')
- return qualify_syscall_number(token, set) || ignore_fail;
+ return parse_syscall_number(token, set) || ignore_fail;
if (*token == '/')
- return qualify_syscall_regex(token + 1, set) || ignore_fail;
- return qualify_syscall_class(token, set)
- || qualify_syscall_name(token, set)
+ return parse_syscall_regex(token + 1, set) || ignore_fail;
+ return parse_syscall_class(token, set)
+ || parse_syscall_name(token, set)
|| ignore_fail;
}
-/*
- * Add syscall numbers to SETs for each supported personality
- * according to STR specification.
- */
-void
-qualify_syscall_tokens(const char *const str, struct number_set *const set,
- const char *const name)
+static void
+parse_syscall_set(const char *const str, struct number_set *const set,
+ const char *const name)
{
/* Clear all sets. */
unsigned int p;
@@ -298,7 +301,7 @@ handle_inversion:
for (token = strtok_r(copy, ",", &saveptr); token;
token = strtok_r(NULL, ",", &saveptr)) {
- done = qualify_syscall(token, set);
+ done = parse_syscall(token, set);
if (!done) {
error_msg_and_die("invalid %s '%s'", name, token);
}
@@ -311,11 +314,37 @@ handle_inversion:
}
}
-/*
- * Add numbers to SET according to STR specification.
- */
+void*
+parse_syscall_filter(const char *str, const char *const name)
+{
+ struct number_set *set = xcalloc(SUPPORTED_PERSONALITIES,
+ sizeof(struct number_set));
+ parse_syscall_set(str, set, name);
+ return set;
+}
+
+bool
+run_syscall_filter(struct tcb *tcp, void *_priv_data)
+{
+ struct number_set *set = (struct number_set *)_priv_data;
+ return is_number_in_set(tcp->scno, &set[current_personality]);
+}
+
void
-qualify_tokens(const char *const str, struct number_set *const set,
+free_syscall_filter(void *_priv_data)
+{
+ struct number_set *set = (struct number_set *)_priv_data;
+ unsigned int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
+ free(set[p].vec);
+ }
+ free(set);
+}
+
+typedef int (*string_to_uint_func)(const char *);
+
+void
+parse_set(const char *const str, struct number_set *const set,
string_to_uint_func func, const char *const name)
{
/* Clear the set. */
@@ -373,3 +402,31 @@ handle_inversion:
error_msg_and_die("invalid %s '%s'", name, str);
}
}
+
+void*
+parse_fd_filter(const char *str, const char *const name)
+{
+ struct number_set *set = xmalloc(sizeof(struct number_set));
+ memset(set, 0, sizeof(struct number_set));
+ parse_set(str, set, string_to_uint, name);
+ return set;
+}
+
+bool
+run_fd_filter(struct tcb *tcp, void *_priv_data)
+{
+ int fd = tcp->u_arg[0];
+ if (fd < 0)
+ return false;
+ struct number_set *set = (struct number_set *)_priv_data;
+ return is_number_in_set(fd, set);
+}
+
+void
+free_fd_filter(void *_priv_data)
+{
+ struct number_set *set = (struct number_set *)_priv_data;
+ free(set->vec);
+ free(set);
+ return;
+}
diff --git a/defs.h b/defs.h
index 29a681b..9242b16 100644
--- a/defs.h
+++ b/defs.h
@@ -228,7 +228,7 @@ struct tcb {
void (*_free_priv_data)(void *); /* Callback for freeing priv_data */
const struct_sysent *s_ent; /* sysent[scno] or dummy struct for bad
scno */
const struct_sysent *s_prev_ent; /* for "resuming interrupted SYSCALL"
msg */
- struct inject_opts *inject_vec[SUPPORTED_PERSONALITIES];
+ struct inject_opts *inject_opts;
struct timeval stime; /* System time usage as of last process wait */
struct timeval dtime; /* Delta for system time usage */
struct timeval etime; /* Syscall entry time */
@@ -272,8 +272,8 @@ struct tcb {
#define QUAL_RAW 0x008 /* print all args in hex for this syscall */
#define QUAL_INJECT 0x010 /* tamper with this system call on purpose */
#define QUAL_SIGNAL 0x100 /* report events with this signal */
-#define QUAL_READ 0x200 /* dump data read from this file descriptor */
-#define QUAL_WRITE 0x400 /* dump data written to this file descriptor */
+#define QUAL_READ 0x200 /* dump data read in this syscall */
+#define QUAL_WRITE 0x400 /* dump data written in this syscall */
#define DEFAULT_QUAL_FLAGS (QUAL_TRACE | QUAL_ABBREV | QUAL_VERBOSE)
@@ -665,13 +665,12 @@ print_struct_statfs64(struct tcb *, kernel_ulong_t addr,
kernel_ulong_t size);
extern void print_ifindex(unsigned int);
struct number_set;
-extern struct number_set read_set;
-extern struct number_set write_set;
extern struct number_set signal_set;
-extern bool is_number_in_set(unsigned int number, const struct number_set *);
-extern void qualify(const char *);
-extern unsigned int qual_flags(const unsigned int);
+extern bool is_number_in_set(const unsigned int, const struct number_set *);
+extern void sort_filter_actions(void);
+extern void filter_syscall(struct tcb *);
+extern void parse_qualify_filter(const char *);
#define DECL_IOCTL(name) \
extern int \
diff --git a/filter.c b/filter.c
new file mode 100644
index 0000000..1f2d2eb
--- /dev/null
+++ b/filter.c
@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2017 Nikolay Marchuk <marchuk.nikola...@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "defs.h"
+#include <ctype.h>
+#include "filter.h"
+
+#define DECL_FILTER(name) \
+extern void* \
+parse_ ## name ## _filter(const char *, const char *const); \
+extern bool \
+run_ ## name ## _filter(struct tcb *, void *); \
+extern void \
+free_ ## name ## _filter(void *)
+DECL_FILTER(syscall);
+DECL_FILTER(fd);
+DECL_FILTER(path);
+#undef DECL_FILTER
+
+#define FILTER_TYPE(name) \
+{#name, sizeof(#name) - 1, parse_ ## name ## _filter, \
+ run_ ## name ## _filter, free_ ## name ## _filter}
+
+static const struct filter_type {
+ const char *name;
+ const size_t name_len;
+ void *(*parse_filter)(const char *, const char *const);
+ bool (*run_filter)(struct tcb *, void *);
+ void (*free_priv_data)(void *);
+} filter_types[] = {
+ FILTER_TYPE(syscall),
+ FILTER_TYPE(fd)
+};
+
+#undef FILTER_TYPE
+
+struct filter {
+ const struct filter_type *type;
+ void *_priv_data;
+};
+
+static const struct filter_type *
+lookup_filter_type(const char *str)
+{
+ unsigned int i;
+ for (i = 0; i < ARRAY_SIZE(filter_types); i++) {
+ const char *name = filter_types[i].name;
+ const size_t len = filter_types[i].name_len;
+ if (!strncmp(name, str, len) && !isalpha(str[len])) {
+ return &filter_types[i];
+ }
+ }
+ return NULL;
+}
+
+struct filter *
+add_filter_to_array(struct filter **filters, unsigned int *nfilters,
+ const char *name)
+{
+ const struct filter_type *type = lookup_filter_type(name);
+ if (!type)
+ return NULL;
+ *filters = xreallocarray(*filters, ++(*nfilters),
+ sizeof(struct filter));
+ struct filter *filter = &((*filters)[*nfilters - 1]);
+ filter->type = type;
+ return filter;
+}
+
+void
+parse_filter(struct filter *filter, const char *str, const char *const name)
+{
+ filter->_priv_data = filter->type->parse_filter(str, name);
+}
+
+static bool
+run_filter(struct tcb *tcp, struct filter *filter)
+{
+ return filter->type->run_filter(tcp, filter->_priv_data);
+}
+
+bool *
+run_filters(struct tcb *tcp, struct filter *filters, unsigned int nfilters)
+{
+ bool *variables = xcalloc(nfilters, sizeof(bool));
+ unsigned int i;
+ for (i = 0; i < nfilters; ++i) {
+ variables[i] = run_filter(tcp, &filters[i]);
+ }
+ return variables;
+}
+
+void
+free_filter(struct filter *filter)
+{
+ if (!filter)
+ return;
+ filter->type->free_priv_data(filter->_priv_data);
+}
+
+void *
+get_filter_priv_data(struct filter *filter)
+{
+ return filter ? filter->_priv_data : NULL;
+}
+
+void
+set_filter_priv_data(struct filter *filter, void *_priv_data)
+{
+ if (filter)
+ filter->_priv_data = _priv_data;
+}
+
+void
+set_filters_qualify_mode(struct filter **filters, unsigned int *nfilters)
+{
+ unsigned int i;
+ for (i = 0; i < *nfilters - 1; ++i) {
+ free_filter(*filters + i);
+ }
+ **filters = (*filters)[*nfilters - 1];
+ *filters = xreallocarray(*filters, 1, sizeof(struct filter));
+ *nfilters = 1;
+}
diff --git a/filter.h b/filter.h
index a798199..ed435c8 100644
--- a/filter.h
+++ b/filter.h
@@ -28,11 +28,37 @@
# define STRACE_FILTER_H
# include "defs.h"
+struct filter;
+
+struct filter_action;
+
+struct bool_expression;
+
+bool is_empty(const struct number_set *);
+
+extern bool is_traced(struct tcb *);
+
typedef int (*string_to_uint_func)(const char *);
+void parse_set(const char *const, struct number_set *const,
+ string_to_uint_func, const char *const);
+
+struct filter* add_filter_to_array(struct filter **, unsigned int *nfilters,
+ const char *name);
+void parse_filter(struct filter *, const char *str, const char *const name);
+bool *run_filters(struct tcb *, struct filter *, unsigned int);
+void free_filter(struct filter *);
+void *get_filter_priv_data(struct filter *);
+void set_filter_priv_data(struct filter *, void *);
+void set_filters_qualify_mode(struct filter **, unsigned int *nfilters);
+
+struct filter *create_filter(struct filter_action *, const char *name);
+void set_qualify_mode(struct filter_action *);
+struct filter_action *find_or_add_action(const char *);
+void *get_filter_action_priv_data(struct filter_action *);
+void set_filter_action_priv_data(struct filter_action *, void *);
+
+struct bool_expression *create_expression();
+void set_expression_qualify_mode(struct bool_expression *);
+bool run_expression(struct bool_expression *, unsigned int, bool *);
-void add_number_to_set(const unsigned int, struct number_set *const);
-void qualify_tokens(const char *const, struct number_set *const,
- string_to_uint_func, const char *const);
-void qualify_syscall_tokens(const char *const, struct number_set *const,
- const char *const);
#endif
diff --git a/filter_action.c b/filter_action.c
new file mode 100644
index 0000000..f71f140
--- /dev/null
+++ b/filter_action.c
@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 2017 Nikolay Marchuk <marchuk.nikola...@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "defs.h"
+#include <ctype.h>
+#include "filter.h"
+
+#define DECL_FILTER_ACTION(name) \
+extern void \
+apply_ ## name(struct tcb *, void *)
+
+DECL_FILTER_ACTION(trace);
+DECL_FILTER_ACTION(inject);
+DECL_FILTER_ACTION(read);
+DECL_FILTER_ACTION(write);
+DECL_FILTER_ACTION(raw);
+DECL_FILTER_ACTION(abbrev);
+DECL_FILTER_ACTION(verbose);
+
+#undef DECL_FILTER_ACTION
+
+#define DECL_FILTER_ACTION_PARSER(name) \
+extern void * \
+parse_ ## name(const char *); \
+extern void \
+free_ ## name(void *)
+
+DECL_FILTER_ACTION_PARSER(null);
+DECL_FILTER_ACTION_PARSER(inject);
+
+#undef DECL_FILTER_ACTION_PARSER
+
+#define FILTER_ACTION_TYPE(NAME, PRIORITY, PARSER, PREFILTER) \
+{#NAME, sizeof(#NAME) - 1,PRIORITY, parse_ ## PARSER, free_ ## PARSER, \
+ PREFILTER, apply_ ## NAME}
+
+static const struct filter_action_type {
+ const char *name;
+ const size_t name_len;
+ unsigned int priority;
+ void *(*parse_args)(const char *);
+ void (*free_priv_data)(void *);
+ bool (*prefilter)(struct tcb *);
+ void (*apply)(struct tcb *, void *);
+} action_types[] = {
+ FILTER_ACTION_TYPE(trace, 2, null, NULL),
+ FILTER_ACTION_TYPE(inject, 2, inject, NULL),
+ FILTER_ACTION_TYPE(read, 1, null, is_traced),
+ FILTER_ACTION_TYPE(write, 1, null, is_traced),
+ FILTER_ACTION_TYPE(raw, 1, null, is_traced),
+ FILTER_ACTION_TYPE(abbrev, 1, null, is_traced),
+ FILTER_ACTION_TYPE(verbose, 1, null, is_traced)
+};
+
+#undef FILTER_ACTION_TYPE
+
+struct filter_action {
+ const struct filter_action_type *type;
+ struct bool_expression *expr;
+ unsigned int nfilters;
+ struct filter *filters;
+ void* _priv_data;
+};
+
+static struct filter_action *filter_actions;
+static unsigned int nfilter_actions;
+
+static int
+compare_action_priority(const void *a, const void *b)
+{
+ unsigned int priority_a = ((struct filter_action *)a)->type->priority;
+ unsigned int priority_b = ((struct filter_action *)b)->type->priority;
+ return (priority_a > priority_b) ? -1 :
+ (priority_a < priority_b) ? 1 : 0;
+}
+
+void
+sort_filter_actions(void)
+{
+ qsort(filter_actions, nfilter_actions, sizeof(struct filter_action),
+ &compare_action_priority);
+}
+
+static const struct filter_action_type *
+lookup_filter_action_type(const char *str)
+{
+ unsigned int i;
+ for (i = 0; i < ARRAY_SIZE(action_types); ++i) {
+ const char *name = action_types[i].name;
+ const size_t len = action_types[i].name_len;
+ if (!strncmp(name, str, len) && !isalpha(str[len])) {
+ return &action_types[i];
+ }
+ }
+ return NULL;
+}
+
+static struct filter_action *
+add_action(const char *name)
+{
+ const struct filter_action_type *type = lookup_filter_action_type(name);
+ if (!type)
+ error_msg_and_die("invalid filter action '%s'", name);
+ filter_actions = xreallocarray(filter_actions, ++nfilter_actions,
+ sizeof(struct filter_action));
+ struct filter_action *action = &filter_actions[nfilter_actions - 1];
+ memset(action, 0, sizeof(*action));
+ action->type = type;
+ action->expr = create_expression();
+ return action;
+}
+
+struct filter_action *
+find_or_add_action(const char *name)
+{
+ const struct filter_action_type *type = lookup_filter_action_type(name);
+ if (!type)
+ error_msg_and_die("invalid filter action '%s'", name);
+ if (type->parse_args != &parse_null)
+ return add_action(name);
+ unsigned int i;
+ for (i = 0; i < nfilter_actions; i++) {
+ if (filter_actions[i].type == type)
+ return &filter_actions[i];
+ }
+ return add_action(name);
+}
+
+static void
+run_filter_action(struct tcb *tcp, struct filter_action *action)
+{
+ if (action->type->prefilter && !action->type->prefilter(tcp))
+ return;
+ bool *variables = run_filters(tcp, action->filters, action->nfilters);
+ bool res = run_expression(action->expr, action->nfilters, variables);
+ free(variables);
+ if (res) {
+ action->type->apply(tcp, action->_priv_data);
+ }
+}
+
+struct filter *
+create_filter(struct filter_action *action, const char *name)
+{
+ if (!action)
+ error_msg_and_die("invalid filter action");
+ return add_filter_to_array(&action->filters,
+ &action->nfilters, name);
+}
+
+void
+set_qualify_mode(struct filter_action *action)
+{
+ if ((!action) || action->nfilters == 0)
+ error_msg_and_die("invalid filter action");
+ set_filters_qualify_mode(&action->filters, &action->nfilters);
+ set_expression_qualify_mode(action->expr);
+}
+
+void
+filter_syscall(struct tcb *tcp)
+{
+ unsigned int i;
+ for (i = 0; i < nfilter_actions; i++) {
+ run_filter_action(tcp, &filter_actions[i]);
+ }
+}
+
+void *
+get_filter_action_priv_data(struct filter_action *action)
+{
+ return action ? action->_priv_data : NULL;
+}
+
+void
+set_filter_action_priv_data(struct filter_action *action, void *_priv_data)
+{
+ if (action)
+ action->_priv_data = _priv_data;
+}
diff --git a/filter_expression.c b/filter_expression.c
new file mode 100644
index 0000000..ca02280
--- /dev/null
+++ b/filter_expression.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (c) 2017 Nikolay Marchuk <marchuk.nikola...@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "defs.h"
+
+struct expression_token{
+ enum token_type{
+ TOK_VARIABLE,
+ TOK_OPERATOR
+ } type;
+ union token_data{
+ unsigned int variable_id;
+ enum operator_type{
+ OP_NOT,
+ OP_AND,
+ OP_OR
+ } operator_id;
+ } data;
+};
+
+struct bool_expression{
+ unsigned int ntokens;
+ struct expression_token *tokens;
+};
+
+struct bool_expression *
+create_expression(void)
+{
+ struct bool_expression *expr = xmalloc(sizeof(struct bool_expression));
+ memset(expr, 0, sizeof(struct bool_expression));
+ return expr;
+}
+
+static void
+reallocate_expression(struct bool_expression *const expr, const unsigned int
new_ntokens)
+{
+ if (new_ntokens <= expr->ntokens)
+ return;
+ expr->tokens = xreallocarray(expr->tokens, new_ntokens,
+ sizeof(*expr->tokens));
+ memset(expr->tokens + expr->ntokens, 0,
+ sizeof(*expr->tokens) * (new_ntokens - expr->ntokens));
+ expr->ntokens = new_ntokens;
+}
+
+#define STACK_SIZE 32
+static bool stack[STACK_SIZE];
+
+void
+set_expression_qualify_mode(struct bool_expression *expr)
+{
+ if (!expr)
+ error_msg_and_die("invalid expression");
+ reallocate_expression(expr, 1);
+ expr->tokens[0].type = TOK_VARIABLE;
+ expr->tokens[0].data.variable_id = 0;
+}
+
+bool
+run_expression(struct bool_expression *expr,
+ unsigned int variables_num, bool *variables)
+{
+ /* Current stack index */
+ unsigned int index = 0;
+ struct expression_token *tok = expr->tokens;
+ struct expression_token *const tok_end = expr->tokens + expr->ntokens;
+ for (; tok != tok_end; ++tok) {
+ switch (tok->type) {
+ case TOK_VARIABLE:
+ if (index == STACK_SIZE)
+ error_msg_and_die("stack overflow");
+ if (tok->data.variable_id >= variables_num)
+ error_msg_and_die("corrupted filter "
+ "expression");
+ stack[index] = variables[tok->data.variable_id];
+ index++;
+ break;
+ case TOK_OPERATOR:
+ switch (tok->data.operator_id) {
+ case OP_NOT:
+ if (index == 0)
+ error_msg_and_die("corrupted filter "
+ "expression");
+ stack[index - 1] = !stack[index - 1];
+ break;
+ case OP_AND:
+ if (index < 2)
+ error_msg_and_die("corrupted filter "
+ "expression");
+ stack[index - 2] = stack[index - 2]
+ && stack[index - 1];
+ --index;
+ break;
+ case OP_OR:
+ if (index < 2)
+ error_msg_and_die("corrupted filter "
+ "expression");
+ stack[index - 2] = stack[index - 2]
+ || stack[index - 1];
+ --index;
+ break;
+ }
+ }
+ }
+ if (index != 1)
+ error_msg_and_die("corrupted filter expression");
+ return stack[0];
+}
diff --git a/filter_qualify.c b/filter_qualify.c
index e23a9f1..6020ce8 100644
--- a/filter_qualify.c
+++ b/filter_qualify.c
@@ -25,13 +25,11 @@
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
-
#include "defs.h"
#include "nsig.h"
#include "filter.h"
typedef unsigned int number_slot_t;
-#define BITS_PER_SLOT (sizeof(number_slot_t) * 8)
struct number_set {
number_slot_t *vec;
@@ -39,16 +37,8 @@ struct number_set {
bool not;
};
-struct number_set read_set;
-struct number_set write_set;
struct number_set signal_set;
-static struct number_set abbrev_set[SUPPORTED_PERSONALITIES];
-static struct number_set inject_set[SUPPORTED_PERSONALITIES];
-static struct number_set raw_set[SUPPORTED_PERSONALITIES];
-static struct number_set trace_set[SUPPORTED_PERSONALITIES];
-static struct number_set verbose_set[SUPPORTED_PERSONALITIES];
-
static int
find_errno_by_name(const char *name)
{
@@ -184,49 +174,67 @@ parse_error:
}
static void
-qualify_read(const char *const str)
+parse_read(const char *const str)
{
- qualify_tokens(str, &read_set, string_to_uint, "descriptor");
+ struct filter_action *action = find_or_add_action("read");
+ struct filter *filter = create_filter(action, "fd");
+ parse_filter(filter, str, "descriptor");
+ set_qualify_mode(action);
}
static void
-qualify_write(const char *const str)
+parse_write(const char *const str)
{
- qualify_tokens(str, &write_set, string_to_uint, "descriptor");
+ struct filter_action *action = find_or_add_action("write");
+ struct filter *filter = create_filter(action, "fd");
+ parse_filter(filter, str, "descriptor");
+ set_qualify_mode(action);
}
static void
qualify_signals(const char *const str)
{
- qualify_tokens(str, &signal_set, sigstr_to_uint, "signal");
+ parse_set(str, &signal_set, sigstr_to_uint, "signal");
}
static void
-qualify_trace(const char *const str)
+parse_trace(const char *const str)
{
- qualify_syscall_tokens(str, trace_set, "system call");
+ struct filter_action *action = find_or_add_action("trace");
+ struct filter *filter = create_filter(action, "syscall");
+ parse_filter(filter, str, "system call");
+ set_qualify_mode(action);
}
static void
-qualify_abbrev(const char *const str)
+parse_abbrev(const char *const str)
{
- qualify_syscall_tokens(str, abbrev_set, "system call");
+ struct filter_action *action = find_or_add_action("abbrev");
+ struct filter *filter = create_filter(action, "syscall");
+ parse_filter(filter, str, "system call");
+ set_qualify_mode(action);
}
static void
-qualify_verbose(const char *const str)
+parse_verbose(const char *const str)
{
- qualify_syscall_tokens(str, verbose_set, "system call");
+ struct filter_action *action = find_or_add_action("verbose");
+ struct filter *filter = create_filter(action, "syscall");
+ parse_filter(filter, str, "system call");
+ set_qualify_mode(action);
}
static void
-qualify_raw(const char *const str)
+parse_raw(const char *const str)
{
- qualify_syscall_tokens(str, raw_set, "system call");
+ struct filter_action *action = find_or_add_action("raw");
+ struct filter *filter = create_filter(action, "syscall");
+ parse_filter(filter, str, "system call");
+ set_qualify_mode(action);
}
static void
-qualify_inject_common(const char *const str,
+parse_inject_common(const char *const str,
const bool fault_tokens_only,
const char *const description)
{
@@ -253,19 +261,23 @@ qualify_inject_common(const char *const str,
}
}
- struct number_set tmp_set[SUPPORTED_PERSONALITIES];
- memset(tmp_set, 0, sizeof(tmp_set));
- qualify_syscall_tokens(name, tmp_set, description);
+ struct filter_action *action = find_or_add_action("inject");
+ struct filter *filter = create_filter(action, "syscall");
+ parse_filter(filter, name, description);
+ set_qualify_mode(action);
free(buf);
-
+ const struct number_set *tmp_set = (const struct number_set *)
+ get_filter_priv_data(filter);
+ struct inject_opts **inject_vec = xcalloc(SUPPORTED_PERSONALITIES,
+ sizeof(struct inject_opts *));
/*
* Initialize inject_vec accourding to tmp_set.
- * Merge tmp_set into inject_set.
*/
+
unsigned int p;
for (p = 0; p < SUPPORTED_PERSONALITIES; ++p) {
- if (!tmp_set[p].nslots && !tmp_set[p].not) {
+ if (is_empty(&tmp_set[p])) {
continue;
}
@@ -277,54 +289,53 @@ qualify_inject_common(const char *const str,
unsigned int i;
for (i = 0; i < nsyscall_vec[p]; ++i) {
if (is_number_in_set(i, &tmp_set[p])) {
- add_number_to_set(i, &inject_set[p]);
inject_vec[p][i] = opts;
}
}
-
- free(tmp_set[p].vec);
}
+ set_filter_action_priv_data(action, inject_vec);
}
static void
-qualify_fault(const char *const str)
+parse_fault(const char *const str)
{
- qualify_inject_common(str, true, "fault argument");
+ parse_inject_common(str, true, "fault argument");
}
static void
-qualify_inject(const char *const str)
+parse_inject(const char *const str)
{
- qualify_inject_common(str, false, "inject argument");
+ parse_inject_common(str, false, "inject argument");
}
static const struct qual_options {
const char *name;
void (*qualify)(const char *);
} qual_options[] = {
- { "trace", qualify_trace },
- { "t", qualify_trace },
- { "abbrev", qualify_abbrev },
- { "a", qualify_abbrev },
- { "verbose", qualify_verbose },
- { "v", qualify_verbose },
- { "raw", qualify_raw },
- { "x", qualify_raw },
+ { "trace", parse_trace },
+ { "t", parse_trace },
+ { "abbrev", parse_abbrev },
+ { "a", parse_abbrev },
+ { "verbose", parse_verbose },
+ { "v", parse_verbose },
+ { "raw", parse_raw },
+ { "x", parse_raw },
{ "signal", qualify_signals },
{ "signals", qualify_signals },
{ "s", qualify_signals },
- { "read", qualify_read },
- { "reads", qualify_read },
- { "r", qualify_read },
- { "write", qualify_write },
- { "writes", qualify_write },
- { "w", qualify_write },
- { "fault", qualify_fault },
- { "inject", qualify_inject },
+ { "read", parse_read },
+ { "reads", parse_read },
+ { "r", parse_read },
+ { "write", parse_write },
+ { "writes", parse_write },
+ { "w", parse_write },
+ { "fault", parse_fault },
+ { "inject", parse_inject },
};
+
void
-qualify(const char *str)
+parse_qualify_filter(const char *str)
{
const struct qual_options *opt = qual_options;
unsigned int i;
@@ -340,21 +351,5 @@ qualify(const char *str)
opt = &qual_options[i];
break;
}
-
opt->qualify(str);
}
-
-unsigned int
-qual_flags(const unsigned int scno)
-{
- return (is_number_in_set(scno, &trace_set[current_personality])
- ? QUAL_TRACE : 0)
- | (is_number_in_set(scno, &abbrev_set[current_personality])
- ? QUAL_ABBREV : 0)
- | (is_number_in_set(scno, &verbose_set[current_personality])
- ? QUAL_VERBOSE : 0)
- | (is_number_in_set(scno, &raw_set[current_personality])
- ? QUAL_RAW : 0)
- | (is_number_in_set(scno, &inject_set[current_personality])
- ? QUAL_INJECT : 0);
-}
diff --git a/strace.c b/strace.c
index 614ab9e..e48ed76 100644
--- a/strace.c
+++ b/strace.c
@@ -822,10 +822,6 @@ droptcb(struct tcb *tcp)
if (tcp->pid == 0)
return;
- int p;
- for (p = 0; p < SUPPORTED_PERSONALITIES; ++p)
- free(tcp->inject_vec[p]);
-
free_tcb_priv_data(tcp);
#ifdef USE_LIBUNWIND
@@ -1626,13 +1622,13 @@ init(int argc, char *argv[])
shared_log = stderr;
set_sortby(DEFAULT_SORTBY);
set_personality(DEFAULT_PERSONALITY);
- qualify("trace=all");
- qualify("abbrev=all");
- qualify("verbose=all");
+ parse_qualify_filter("trace=all");
+ parse_qualify_filter("abbrev=all");
+ parse_qualify_filter("verbose=all");
#if DEFAULT_QUAL_FLAGS != (QUAL_TRACE | QUAL_ABBREV | QUAL_VERBOSE)
# error Bug in DEFAULT_QUAL_FLAGS
#endif
- qualify("signal=all");
+ parse_qualify_filter("signal=all");
while ((c = getopt(argc, argv,
"+b:cCdfFhiqrtTvVwxyz"
#ifdef USE_LIBUNWIND
@@ -1699,7 +1695,7 @@ init(int argc, char *argv[])
show_fd_path++;
break;
case 'v':
- qualify("abbrev=none");
+ parse_qualify_filter("abbrev=none");
break;
case 'V':
print_version();
@@ -1714,7 +1710,7 @@ init(int argc, char *argv[])
error_opt_arg(c, optarg);
break;
case 'e':
- qualify(optarg);
+ parse_qualify_filter(optarg);
break;
case 'o':
outfname = xstrdup(optarg);
@@ -1762,6 +1758,8 @@ init(int argc, char *argv[])
break;
}
}
+ sort_filter_actions();
+
argv += optind;
/* argc -= optind; - no need, argc is not used below */
@@ -2459,6 +2457,8 @@ trace_syscall(struct tcb *tcp, unsigned int *sig)
case 0:
return 0;
case 1:
+ if (!tcp->qual_flg)
+ filter_syscall(tcp);
res = syscall_entering_trace(tcp, sig);
}
syscall_entering_finish(tcp, res);
diff --git a/syscall.c b/syscall.c
index 02626c7..b6e1ba3 100644
--- a/syscall.c
+++ b/syscall.c
@@ -382,7 +382,6 @@ decode_socket_subcall(struct tcb *tcp)
return;
tcp->scno = scno;
- tcp->qual_flg = qual_flags(scno);
tcp->s_ent = &sysent[scno];
unsigned int i;
@@ -422,7 +421,6 @@ decode_ipc_subcall(struct tcb *tcp)
}
tcp->scno = SYS_ipc_subcall + call;
- tcp->qual_flg = qual_flags(tcp->scno);
tcp->s_ent = &sysent[tcp->scno];
const unsigned int n = tcp->s_ent->nargs;
@@ -439,7 +437,6 @@ decode_mips_subcall(struct tcb *tcp)
if (!scno_is_valid(tcp->u_arg[0]))
return;
tcp->scno = tcp->u_arg[0];
- tcp->qual_flg = qual_flags(tcp->scno);
tcp->s_ent = &sysent[tcp->scno];
memmove(&tcp->u_arg[0], &tcp->u_arg[1],
sizeof(tcp->u_arg) - sizeof(tcp->u_arg[0]));
@@ -468,7 +465,7 @@ dumpio(struct tcb *tcp)
if (fd < 0)
return;
- if (is_number_in_set(fd, &read_set)) {
+ if (tcp->qual_flg & QUAL_READ) {
switch (tcp->s_ent->sen) {
case SEN_read:
case SEN_pread:
@@ -491,7 +488,7 @@ dumpio(struct tcb *tcp)
return;
}
}
- if (is_number_in_set(fd, &write_set)) {
+ if (tcp->qual_flg & QUAL_WRITE) {
switch (tcp->s_ent->sen) {
case SEN_write:
case SEN_pwrite:
@@ -577,28 +574,10 @@ static void get_error(struct tcb *, const bool);
static int arch_set_error(struct tcb *);
static int arch_set_success(struct tcb *);
-struct inject_opts *inject_vec[SUPPORTED_PERSONALITIES];
-
-static struct inject_opts *
-tcb_inject_opts(struct tcb *tcp)
-{
- return (scno_in_range(tcp->scno) &&
tcp->inject_vec[current_personality])
- ? &tcp->inject_vec[current_personality][tcp->scno] : NULL;
-}
-
-
static long
tamper_with_syscall_entering(struct tcb *tcp, unsigned int *signo)
{
- if (!tcp->inject_vec[current_personality]) {
- tcp->inject_vec[current_personality] =
- xcalloc(nsyscalls, sizeof(**inject_vec));
- memcpy(tcp->inject_vec[current_personality],
- inject_vec[current_personality],
- nsyscalls * sizeof(**inject_vec));
- }
-
- struct inject_opts *opts = tcb_inject_opts(tcp);
+ struct inject_opts *opts = tcp->inject_opts;
if (!opts || opts->first == 0)
return 0;
@@ -621,7 +600,7 @@ tamper_with_syscall_entering(struct tcb *tcp, unsigned int
*signo)
static long
tamper_with_syscall_exiting(struct tcb *tcp)
{
- struct inject_opts *opts = tcb_inject_opts(tcp);
+ struct inject_opts *opts = tcp->inject_opts;
if (!opts)
return 0;
@@ -1258,7 +1237,7 @@ get_scno(struct tcb *tcp)
if (scno_is_valid(tcp->scno)) {
tcp->s_ent = &sysent[tcp->scno];
- tcp->qual_flg = qual_flags(tcp->scno);
+ tcp->qual_flg = 0;
} else {
struct sysent_buf *s = xcalloc(1, sizeof(*s));
--
2.1.4
------------------------------------------------------------------------------
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