This change introduces new filtering architecture primitives: filter, filter_action and bool_expression. Filtering is now done after decoding of syscall and tcp->qual_flg stores filtering results.
* basic_actions.c: New file. * filter_action.c: Likewise. * filter_expression.c: Likewise. * filter.c: Likewise. * basic_filters.c (parse_syscall_filter, run_syscall_filter, free_syscall_filter): New functions. * defs.h (filter_syscall, filtering_parsing_finish): Add new declarations. * filter.h: Add new declarations. * filter_qualify.c (abbrev_set, raw_set, trace_set, verbose_set): Remove set variables. (qualify_trace, qualify_abbrev, qualify_verbose, qualify_raw): Use new filtering API. (qual_flags): Remove QUAL_* flags for trace, abbrev, verbose, raw. * strace.c (init): Call filtering_parse_finish after command line parsing. (trace_syscall): Add filtering after syscall decoding. * Makefile.am (strace_SOURCES): Add new files. --- Makefile.am | 4 + basic_actions.c | 65 ++++++++++++++ basic_filters.c | 26 ++++++ defs.h | 2 + filter.c | 121 +++++++++++++++++++++++++ filter.h | 58 ++++++++++++ filter_action.c | 183 +++++++++++++++++++++++++++++++++++++ filter_expression.c | 255 ++++++++++++++++++++++++++++++++++++++++++++++++++++ filter_qualify.c | 48 +++++----- strace.c | 2 + 10 files changed, 738 insertions(+), 26 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 b3afc7c5..b928eb28 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 \ bind.c \ bjm.c \ @@ -133,7 +134,10 @@ 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 \ flock.c \ flock.h \ diff --git a/basic_actions.c b/basic_actions.c new file mode 100644 index 00000000..a9b10ffa --- /dev/null +++ b/basic_actions.c @@ -0,0 +1,65 @@ +/* + * 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 "filter.h" + +bool +is_traced(struct tcb *tcp) +{ + return traced(tcp); +} + +void * +parse_null(const char *str) +{ + return NULL; +} + +void +apply_trace(struct tcb *tcp, void *priv_data) +{ + tcp->qual_flg |= QUAL_TRACE; +} + +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 7b7f0a54..99c6e714 100644 --- a/basic_filters.c +++ b/basic_filters.c @@ -258,6 +258,32 @@ handle_inversion: } } +void * +parse_syscall_filter(const char *str) +{ + struct number_set *set; + + set = alloc_number_set_array(SUPPORTED_PERSONALITIES); + qualify_syscall_tokens(str, set, "system call"); + return set; +} + +bool +run_syscall_filter(struct tcb *tcp, void *priv_data) +{ + struct number_set *set = priv_data; + + return is_number_in_set_array(tcp->scno, set, current_personality); +} + +void +free_syscall_filter(void *priv_data) +{ + struct number_set *set = priv_data; + + free_number_set_array(set, SUPPORTED_PERSONALITIES); +} + /* * Add numbers to SET according to STR specification. */ diff --git a/defs.h b/defs.h index 93f09706..6b143a5a 100644 --- a/defs.h +++ b/defs.h @@ -648,6 +648,8 @@ extern void print_ifindex(unsigned int); extern void qualify(const char *); extern unsigned int qual_flags(const unsigned int); +extern void filtering_parsing_finish(void); +extern void filter_syscall(struct tcb *); #define DECL_IOCTL(name) \ extern int \ diff --git a/filter.c b/filter.c new file mode 100644 index 00000000..d2bc1bfa --- /dev/null +++ b/filter.c @@ -0,0 +1,121 @@ +/* + * 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 "filter.h" + +#define FILTER_TYPE(name) \ +{#name, parse_ ## name ## _filter, run_ ## name ## _filter, \ + free_ ## name ## _filter} +/* End of FILTER_TYPE definition. */ + +static const struct filter_type { + const char *name; + void *(*parse_filter)(const char *); + bool (*run_filter)(struct tcb *, void *); + void (*free_priv_data)(void *); +} filter_types[] = { + FILTER_TYPE(syscall), +}; +#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++) { + if (!strcmp(filter_types[i].name, str)) + 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); + struct filter *filter; + + if (!type) + error_msg_and_die("invalid filter '%s'", name); + *filters = xreallocarray(*filters, ++(*nfilters), + sizeof(struct filter)); + filter = &((*filters)[*nfilters - 1]); + filter->type = type; + return filter; +} + +void +parse_filter(struct filter *filter, const char *str) +{ + filter->priv_data = filter->type->parse_filter(str); +} + +static bool +run_filter(struct tcb *tcp, struct filter *filter) +{ + return filter->type->run_filter(tcp, filter->priv_data); +} + +void +run_filters(struct tcb *tcp, struct filter *filters, unsigned int nfilters, + bool *variables_buf) +{ + unsigned int i; + + for (i = 0; i < nfilters; ++i) + variables_buf[i] = run_filter(tcp, &filters[i]); +} + +void +free_filter(struct filter *filter) +{ + if (!filter) + return; + filter->type->free_priv_data(filter->priv_data); +} + +void +set_filters_qualify_mode(struct filter **filters, unsigned int *nfilters, + unsigned int filters_left) +{ + unsigned int i; + + for (i = 0; i < *nfilters - filters_left; ++i) + free_filter(*filters + i); + for (i = 0; i < filters_left; ++i) + (*filters)[i] = (*filters)[*nfilters - filters_left + i]; + *filters = xreallocarray(*filters, filters_left, sizeof(struct filter)); + *nfilters = filters_left; +} diff --git a/filter.h b/filter.h index fab18127..aa945ceb 100644 --- a/filter.h +++ b/filter.h @@ -30,11 +30,69 @@ #define STRACE_FILTER_H struct number_set; + +struct filter; + +struct filter_action; + +struct bool_expression; + typedef int (*string_to_uint_func)(const char *); void qualify_tokens(const char *str, struct number_set *set, string_to_uint_func func, const char *name); void qualify_syscall_tokens(const char *str, struct number_set *set, const char *name); +bool is_traced(struct tcb *); + +/* filter api */ +struct filter* add_filter_to_array(struct filter **, unsigned int *nfilters, + const char *name); +void parse_filter(struct filter *, const char *str); +void run_filters(struct tcb *, struct filter *, unsigned int, bool *); +void free_filter(struct filter *); +void set_filters_qualify_mode(struct filter **, unsigned int *nfilters, + unsigned int filters_left); + +/* filter action api */ +struct filter *create_filter(struct filter_action *, const char *name); +struct filter_action *find_or_add_action(const char *); +void set_qualify_mode(struct filter_action *, unsigned int); + +/* filter expression api */ +struct bool_expression *create_expression(); +bool run_expression(struct bool_expression *, bool *, unsigned int); +void set_expression_qualify_mode(struct bool_expression *, unsigned int); + +#define DECL_FILTER(name) \ +extern void * \ +parse_ ## name ## _filter(const char *); \ +extern bool \ +run_ ## name ## _filter(struct tcb *, void *); \ +extern void \ +free_ ## name ## _filter(void *) \ +/* End of DECL_FILTER definition. */ + +DECL_FILTER(syscall); +#undef DECL_FILTER + +#define DECL_FILTER_ACTION(name) \ +extern void \ +apply_ ## name(struct tcb *, void *) \ +/* End of DECL_FILTER_ACTION definition. */ + +DECL_FILTER_ACTION(trace); +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 *); \ +/* End of DECL_FILTER_ACTION_PARSER definition. */ + +DECL_FILTER_ACTION_PARSER(null); +#undef DECL_FILTER_ACTION_PARSER #endif /* !STRACE_FILTER_H */ diff --git a/filter_action.c b/filter_action.c new file mode 100644 index 00000000..8092cdec --- /dev/null +++ b/filter_action.c @@ -0,0 +1,183 @@ +/* + * 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 "filter.h" + +#define FILTER_ACTION_TYPE(NAME, PRIORITY, FLAG, PARSER, PREFILTER) \ +{#NAME, PRIORITY, FLAG, parse_ ## PARSER, PREFILTER, apply_ ## NAME} +/* End of FILTER_ACTION_TYPE definition. */ + +static const struct filter_action_type { + const char *name; + /* The highest priority is 0. */ + unsigned int priority; + unsigned int qual_flg; + void * (*parse_args)(const char *); + bool (*prefilter)(struct tcb *); + void (*apply)(struct tcb *, void *); +} action_types[] = { + FILTER_ACTION_TYPE(trace, 0, QUAL_TRACE, null, NULL), + FILTER_ACTION_TYPE(raw, 2, QUAL_RAW, null, is_traced), + FILTER_ACTION_TYPE(abbrev, 2, QUAL_ABBREV, null, is_traced), + FILTER_ACTION_TYPE(verbose, 2, QUAL_VERBOSE, null, is_traced), +}; +#undef FILTER_ACTION_TYPE + +struct filter_action { + /* Used to correct order of actions with the same priority. */ + unsigned int id; + 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 bool *variables_buf; + +/* + * Compares action priorities. If actions have the same priority, + * uses LIFO order. + */ +static int +compare_action_priority(const void *a, const void *b) +{ + const struct filter_action *action_a = a; + const struct filter_action *action_b = b; + unsigned int priority_a = action_a->type->priority; + unsigned int priority_b = action_b->type->priority; + + if (priority_a != priority_b) { + return (priority_a < priority_b) ? -1 : 1; + } else { + return (action_a->id > action_b->id) ? -1 : 1; + } +} + +void +filtering_parsing_finish(void) +{ + unsigned int maxfilters = 0; + unsigned int i; + + /* Sort actions by priority */ + if (nfilter_actions == 0) + return; + qsort(filter_actions, nfilter_actions, sizeof(struct filter_action), + &compare_action_priority); + + /* Allocate variables_buf sufficient for any action */ + for (i = 0; i < nfilter_actions; ++i) { + if (filter_actions[i].nfilters > maxfilters) + maxfilters = filter_actions[i].nfilters; + } + variables_buf = xcalloc(maxfilters, sizeof(bool)); +} + +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) { + if (!strcmp(action_types[i].name, str)) + return &action_types[i]; + } + return NULL; +} + +static struct filter_action * +add_action(const struct filter_action_type *type) +{ + struct filter_action *action; + + filter_actions = xreallocarray(filter_actions, ++nfilter_actions, + sizeof(struct filter_action)); + action = &filter_actions[nfilter_actions - 1]; + memset(action, 0, sizeof(*action)); + action->id = nfilter_actions - 1; + 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); + unsigned int i; + + if (!type) + error_msg_and_die("invalid filter action '%s'", name); + /* If action takes arguments, add new action */ + if (type->parse_args != &parse_null) + return add_action(type); + + for (i = 0; i < nfilter_actions; ++i) { + if (filter_actions[i].type == type) + return &filter_actions[i]; + } + return add_action(type); +} + +static void +run_filter_action(struct tcb *tcp, struct filter_action *action) +{ + if (action->type->prefilter && !action->type->prefilter(tcp)) + return; + run_filters(tcp, action->filters, action->nfilters, variables_buf); + if (run_expression(action->expr, variables_buf, action->nfilters)) + action->type->apply(tcp, action->priv_data); +} + +struct filter * +create_filter(struct filter_action *action, const char *name) +{ + return add_filter_to_array(&action->filters, &action->nfilters, name); +} + +void +set_qualify_mode(struct filter_action *action, unsigned int filters_left) +{ + set_filters_qualify_mode(&action->filters, &action->nfilters, + filters_left); + set_expression_qualify_mode(action->expr, filters_left); + +} + +void +filter_syscall(struct tcb *tcp) +{ + unsigned int i; + + for (i = 0; i < nfilter_actions; ++i) + run_filter_action(tcp, &filter_actions[i]); +} diff --git a/filter_expression.c b/filter_expression.c new file mode 100644 index 00000000..4c1ff466 --- /dev/null +++ b/filter_expression.c @@ -0,0 +1,255 @@ +/* + * 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 <stdarg.h> +#include "filter.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) +{ + return xcalloc(1, sizeof(struct bool_expression)); +} + +static void +reallocate_expression(struct bool_expression *const expr, + const unsigned int new_ntokens) +{ + if (!expr) + error_msg_and_die("invalid expression"); + expr->tokens = xreallocarray(expr->tokens, new_ntokens, + sizeof(*expr->tokens)); + if (new_ntokens > expr->ntokens) + memset(expr->tokens + expr->ntokens, 0, + sizeof(*expr->tokens) * (new_ntokens - expr->ntokens)); + expr->ntokens = new_ntokens; +} + +void +set_expression_qualify_mode(struct bool_expression *expr, + unsigned int filters_left) +{ + unsigned int i; + + if (!expr) + error_msg_and_die("invalid expression"); + reallocate_expression(expr, 2 * filters_left - 1); + for (i = 0; i < filters_left; ++i) { + expr->tokens[i].type = TOK_VARIABLE; + expr->tokens[i].data.variable_id = i; + } + for (; i < 2 * filters_left - 1; ++i) { + expr->tokens[i].type = TOK_OPERATOR; + expr->tokens[i].data.operator_id = OP_AND; + } +} + +ATTRIBUTE_FORMAT((printf, 3, 4)) +static int +printf_append(char **ptr, char *end, const char *fmt, ...) + { + int ret; + va_list args; + + va_start(args, fmt); + ret = vsnprintf(*ptr, end - *ptr, fmt, args); + va_end(args); + + if (ret < 0) + return ret; + + *ptr += MIN(ret, end - *ptr); + return ret; +} + +/* Print full diagnostics for corrupted expression */ +ATTRIBUTE_NORETURN +static void +handle_corrupted_expression(struct bool_expression *expr, bool *stack, + unsigned int stack_size, unsigned int current_pos, + bool *variables, unsigned int variables_num) +{ + char *buf, *pos, *end; + unsigned int buf_size; + unsigned int i; + + /* Calculate buffer size. */ + buf_size = sizeof("corrupted filter expression:"); + buf_size += sizeof("expression (ntokens = ):") + + 3 * sizeof(unsigned int) + + (sizeof("op_") + 3 * sizeof(int)) * expr->ntokens; + buf_size += sizeof("variables (nvariables = ):") + 3 * sizeof(int) + + sizeof("false") * variables_num; + buf_size += sizeof("current position: ") + 3 * sizeof(int); + buf_size += sizeof("stack (stack_size = ):") + 3 * sizeof(int) + + sizeof("false") * stack_size; + + buf = xcalloc(buf_size, 1); + pos = buf; + end = buf + buf_size; + + printf_append(&pos, end, "corrupted filter expression:\n"); + + /* Print expression. */ + printf_append(&pos, end, "expression (ntokens = %u):", expr->ntokens); + for (i = 0; i < expr->ntokens; ++i) { + switch (expr->tokens[i].type) { + case TOK_VARIABLE: + printf_append(&pos, end, " v_%u", + expr->tokens[i].data.variable_id); + break; + case TOK_OPERATOR: + switch (expr->tokens[i].data.operator_id) { + case OP_NOT: + printf_append(&pos, end, " not"); + break; + case OP_AND: + printf_append(&pos, end, " and"); + break; + case OP_OR: + printf_append(&pos, end, " or"); + break; + default: + printf_append(&pos, end, " op_%d", + expr->tokens[i].data.operator_id); + } + break; + default: + printf_append(&pos, end, " ?_%d", expr->tokens[i].type); + } + } + printf_append(&pos, end, "\n"); + + /* Print variables. */ + printf_append(&pos, end, "variables (nvariables = %u):", variables_num); + for (i = 0; i < variables_num; ++i) + printf_append(&pos, end, !variables[i] ? " false" : " true"); + printf_append(&pos, end, "\n"); + + printf_append(&pos, end, "current position: %u\n", current_pos); + + /* Print current stack state. */ + printf_append(&pos, end, "stack (stack_size = %u):", stack_size); + for (i = 0; i < stack_size; ++i) + printf_append(&pos, end, !stack[i] ? " false" : " true"); + + error_msg_and_die("%s", buf); +} + +#define MAX_STACK_SIZE 32 + +bool +run_expression(struct bool_expression *expr, bool *variables, + unsigned int variables_num) +{ + bool stack[MAX_STACK_SIZE]; + unsigned int stack_size = 0; + unsigned int i; + + for (i = 0; i < expr->ntokens; ++i) { + struct expression_token *tok = &expr->tokens[i]; + + switch (tok->type) { + case TOK_VARIABLE: + if (stack_size == MAX_STACK_SIZE) + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + + if (tok->data.variable_id >= variables_num) + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + stack[stack_size++] = variables[tok->data.variable_id]; + break; + case TOK_OPERATOR: + switch (tok->data.operator_id) { + case OP_NOT: + if (stack_size == 0) + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + stack[stack_size - 1] = !stack[stack_size - 1]; + break; + case OP_AND: + if (stack_size < 2) + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + stack[stack_size - 2] = stack[stack_size - 2] + && stack[stack_size - 1]; + --stack_size; + break; + case OP_OR: + if (stack_size < 2) + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + stack[stack_size - 2] = stack[stack_size - 2] + || stack[stack_size - 1]; + --stack_size; + break; + default: + handle_corrupted_expression(expr, stack, + stack_size, i, + variables, + variables_num); + } + break; + } + } + + if (stack_size != 1) + handle_corrupted_expression(expr, stack, stack_size, i, + variables, variables_num); + return stack[0]; +} diff --git a/filter_qualify.c b/filter_qualify.c index b59b19b9..abcb2b46 100644 --- a/filter_qualify.c +++ b/filter_qualify.c @@ -35,11 +35,7 @@ struct number_set *read_set; struct number_set *write_set; struct number_set *signal_set; -static struct number_set *abbrev_set; static struct number_set *inject_set; -static struct number_set *raw_set; -static struct number_set *trace_set; -static struct number_set *verbose_set; static int sigstr_to_uint(const char *s) @@ -202,33 +198,41 @@ qualify_signals(const char *const str) static void qualify_trace(const char *const str) { - if (!trace_set) - trace_set = alloc_number_set_array(SUPPORTED_PERSONALITIES); - 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); + set_qualify_mode(action, 1); } static void qualify_abbrev(const char *const str) { - if (!abbrev_set) - abbrev_set = alloc_number_set_array(SUPPORTED_PERSONALITIES); - 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); + set_qualify_mode(action, 1); } static void qualify_verbose(const char *const str) { - if (!verbose_set) - verbose_set = alloc_number_set_array(SUPPORTED_PERSONALITIES); - 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); + set_qualify_mode(action, 1); } static void qualify_raw(const char *const str) { - if (!raw_set) - raw_set = alloc_number_set_array(SUPPORTED_PERSONALITIES); - 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); + set_qualify_mode(action, 1); } static void @@ -356,14 +360,6 @@ qualify(const char *str) unsigned int qual_flags(const unsigned int scno) { - return (is_number_in_set_array(scno, trace_set, current_personality) - ? QUAL_TRACE : 0) - | (is_number_in_set_array(scno, abbrev_set, current_personality) - ? QUAL_ABBREV : 0) - | (is_number_in_set_array(scno, verbose_set, current_personality) - ? QUAL_VERBOSE : 0) - | (is_number_in_set_array(scno, raw_set, current_personality) - ? QUAL_RAW : 0) - | (is_number_in_set_array(scno, inject_set, current_personality) - ? QUAL_INJECT : 0); + return is_number_in_set_array(scno, inject_set, current_personality) + ? QUAL_INJECT : 0; } diff --git a/strace.c b/strace.c index 6ed86a6f..bd6d687a 100644 --- a/strace.c +++ b/strace.c @@ -1713,6 +1713,7 @@ init(int argc, char *argv[]) break; } } + filtering_parsing_finish(); argv += optind; argc -= optind; @@ -2415,6 +2416,7 @@ trace_syscall(struct tcb *tcp, unsigned int *sig) case 0: return 0; case 1: + filter_syscall(tcp); res = syscall_entering_trace(tcp, sig); } syscall_entering_finish(tcp, res); -- 2.11.0 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Strace-devel mailing list Strace-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/strace-devel