*
* LTTng modules filter interpreter.
*
- * Copyright (C) 2010-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
- * 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; only
- * version 2.1 of the License.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
*
- * 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.
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
*
- * 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
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
*/
-#include "lttng-filter.h"
+#include <wrapper/uaccess.h>
+#include <wrapper/frame.h>
+#include <wrapper/types.h>
+
+#include <lttng-filter.h>
+#include <lttng-string-utils.h>
+
+LTTNG_STACK_FRAME_NON_STANDARD(lttng_filter_interpret_bytecode);
+
+/*
+ * get_char should be called with page fault handler disabled if it is expected
+ * to handle user-space read.
+ */
+static
+char get_char(struct estack_entry *reg, size_t offset)
+{
+ if (unlikely(offset >= reg->u.s.seq_len))
+ return '\0';
+ if (reg->u.s.user) {
+ char c;
+
+ /* Handle invalid access as end of string. */
+ if (unlikely(!lttng_access_ok(VERIFY_READ,
+ reg->u.s.user_str + offset,
+ sizeof(c))))
+ return '\0';
+ /* Handle fault (nonzero return value) as end of string. */
+ if (unlikely(__copy_from_user_inatomic(&c,
+ reg->u.s.user_str + offset,
+ sizeof(c))))
+ return '\0';
+ return c;
+ } else {
+ return reg->u.s.str[offset];
+ }
+}
/*
* -1: wildcard found.
* -2: unknown escape char.
* 0: normal char.
*/
-
static
-int parse_char(const char **p)
+int parse_char(struct estack_entry *reg, char *c, size_t *offset)
{
- switch (**p) {
+ switch (*c) {
case '\\':
- (*p)++;
- switch (**p) {
+ (*offset)++;
+ *c = get_char(reg, *offset);
+ switch (*c) {
case '\\':
case '*':
return 0;
}
}
+static
+char get_char_at_cb(size_t at, void *data)
+{
+ return get_char(data, at);
+}
+
+static
+int stack_star_glob_match(struct estack *stack, int top, const char *cmp_type)
+{
+ bool has_user = false;
+ int result;
+ struct estack_entry *pattern_reg;
+ struct estack_entry *candidate_reg;
+
+ /* Disable the page fault handler when reading from userspace. */
+ if (estack_bx(stack, top)->u.s.user
+ || estack_ax(stack, top)->u.s.user) {
+ has_user = true;
+ pagefault_disable();
+ }
+
+ /* Find out which side is the pattern vs. the candidate. */
+ if (estack_ax(stack, top)->u.s.literal_type == ESTACK_STRING_LITERAL_TYPE_STAR_GLOB) {
+ pattern_reg = estack_ax(stack, top);
+ candidate_reg = estack_bx(stack, top);
+ } else {
+ pattern_reg = estack_bx(stack, top);
+ candidate_reg = estack_ax(stack, top);
+ }
+
+ /* Perform the match operation. */
+ result = !strutils_star_glob_match_char_cb(get_char_at_cb,
+ pattern_reg, get_char_at_cb, candidate_reg);
+ if (has_user)
+ pagefault_enable();
+
+ return result;
+}
+
static
int stack_strcmp(struct estack *stack, int top, const char *cmp_type)
{
- const char *p = estack_bx(stack, top)->u.s.str, *q = estack_ax(stack, top)->u.s.str;
- int ret;
- int diff;
+ size_t offset_bx = 0, offset_ax = 0;
+ int diff, has_user = 0;
+
+ if (estack_bx(stack, top)->u.s.user
+ || estack_ax(stack, top)->u.s.user) {
+ has_user = 1;
+ pagefault_disable();
+ }
for (;;) {
+ int ret;
int escaped_r0 = 0;
+ char char_bx, char_ax;
+
+ char_bx = get_char(estack_bx(stack, top), offset_bx);
+ char_ax = get_char(estack_ax(stack, top), offset_ax);
- if (unlikely(p - estack_bx(stack, top)->u.s.str > estack_bx(stack, top)->u.s.seq_len || *p == '\0')) {
- if (q - estack_ax(stack, top)->u.s.str > estack_ax(stack, top)->u.s.seq_len || *q == '\0') {
- return 0;
+ if (unlikely(char_bx == '\0')) {
+ if (char_ax == '\0') {
+ diff = 0;
+ break;
} else {
- if (estack_ax(stack, top)->u.s.literal) {
- ret = parse_char(&q);
- if (ret == -1)
- return 0;
+ if (estack_ax(stack, top)->u.s.literal_type ==
+ ESTACK_STRING_LITERAL_TYPE_PLAIN) {
+ ret = parse_char(estack_ax(stack, top),
+ &char_ax, &offset_ax);
+ if (ret == -1) {
+ diff = 0;
+ break;
+ }
}
- return -1;
+ diff = -1;
+ break;
}
}
- if (unlikely(q - estack_ax(stack, top)->u.s.str > estack_ax(stack, top)->u.s.seq_len || *q == '\0')) {
- if (p - estack_bx(stack, top)->u.s.str > estack_bx(stack, top)->u.s.seq_len || *p == '\0') {
- return 0;
- } else {
- if (estack_bx(stack, top)->u.s.literal) {
- ret = parse_char(&p);
- if (ret == -1)
- return 0;
+ if (unlikely(char_ax == '\0')) {
+ if (estack_bx(stack, top)->u.s.literal_type ==
+ ESTACK_STRING_LITERAL_TYPE_PLAIN) {
+ ret = parse_char(estack_bx(stack, top),
+ &char_bx, &offset_bx);
+ if (ret == -1) {
+ diff = 0;
+ break;
}
- return 1;
}
+ diff = 1;
+ break;
}
- if (estack_bx(stack, top)->u.s.literal) {
- ret = parse_char(&p);
+ if (estack_bx(stack, top)->u.s.literal_type ==
+ ESTACK_STRING_LITERAL_TYPE_PLAIN) {
+ ret = parse_char(estack_bx(stack, top),
+ &char_bx, &offset_bx);
if (ret == -1) {
- return 0;
+ diff = 0;
+ break;
} else if (ret == -2) {
escaped_r0 = 1;
}
/* else compare both char */
}
- if (estack_ax(stack, top)->u.s.literal) {
- ret = parse_char(&q);
+ if (estack_ax(stack, top)->u.s.literal_type ==
+ ESTACK_STRING_LITERAL_TYPE_PLAIN) {
+ ret = parse_char(estack_ax(stack, top),
+ &char_ax, &offset_ax);
if (ret == -1) {
- return 0;
+ diff = 0;
+ break;
} else if (ret == -2) {
- if (!escaped_r0)
- return -1;
+ if (!escaped_r0) {
+ diff = -1;
+ break;
+ }
} else {
- if (escaped_r0)
- return 1;
+ if (escaped_r0) {
+ diff = 1;
+ break;
+ }
}
} else {
- if (escaped_r0)
- return 1;
+ if (escaped_r0) {
+ diff = 1;
+ break;
+ }
}
- diff = *p - *q;
+ diff = char_bx - char_ax;
if (diff != 0)
break;
- p++;
- q++;
+ offset_bx++;
+ offset_ax++;
}
+ if (has_user)
+ pagefault_enable();
+
return diff;
}
uint64_t lttng_filter_false(void *filter_data,
+ struct lttng_probe_ctx *lttng_probe_ctx,
const char *filter_stack_data)
{
return 0;
* effect.
*/
uint64_t lttng_filter_interpret_bytecode(void *filter_data,
+ struct lttng_probe_ctx *lttng_probe_ctx,
const char *filter_stack_data)
{
struct bytecode_runtime *bytecode = filter_data;
[ FILTER_OP_GE_STRING ] = &&LABEL_FILTER_OP_GE_STRING,
[ FILTER_OP_LE_STRING ] = &&LABEL_FILTER_OP_LE_STRING,
+ /* globbing pattern binary comparator */
+ [ FILTER_OP_EQ_STAR_GLOB_STRING ] = &&LABEL_FILTER_OP_EQ_STAR_GLOB_STRING,
+ [ FILTER_OP_NE_STAR_GLOB_STRING ] = &&LABEL_FILTER_OP_NE_STAR_GLOB_STRING,
+
/* s64 binary comparator */
[ FILTER_OP_EQ_S64 ] = &&LABEL_FILTER_OP_EQ_S64,
[ FILTER_OP_NE_S64 ] = &&LABEL_FILTER_OP_NE_S64,
/* load from immediate operand */
[ FILTER_OP_LOAD_STRING ] = &&LABEL_FILTER_OP_LOAD_STRING,
+ [ FILTER_OP_LOAD_STAR_GLOB_STRING ] = &&LABEL_FILTER_OP_LOAD_STAR_GLOB_STRING,
[ FILTER_OP_LOAD_S64 ] = &&LABEL_FILTER_OP_LOAD_S64,
[ FILTER_OP_LOAD_DOUBLE ] = &&LABEL_FILTER_OP_LOAD_DOUBLE,
[ FILTER_OP_GET_CONTEXT_REF_STRING ] = &&LABEL_FILTER_OP_GET_CONTEXT_REF_STRING,
[ FILTER_OP_GET_CONTEXT_REF_S64 ] = &&LABEL_FILTER_OP_GET_CONTEXT_REF_S64,
[ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = &&LABEL_FILTER_OP_GET_CONTEXT_REF_DOUBLE,
+
+ /* load userspace field ref */
+ [ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = &&LABEL_FILTER_OP_LOAD_FIELD_REF_USER_STRING,
+ [ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = &&LABEL_FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE,
};
#endif /* #ifndef INTERPRETER_USE_SWITCH */
PO;
}
+ OP(FILTER_OP_EQ_STAR_GLOB_STRING):
+ {
+ int res;
+
+ res = (stack_star_glob_match(stack, top, "==") == 0);
+ estack_pop(stack, top, ax, bx);
+ estack_ax_v = res;
+ next_pc += sizeof(struct binary_op);
+ PO;
+ }
+ OP(FILTER_OP_NE_STAR_GLOB_STRING):
+ {
+ int res;
+
+ res = (stack_star_glob_match(stack, top, "!=") != 0);
+ estack_pop(stack, top, ax, bx);
+ estack_ax_v = res;
+ next_pc += sizeof(struct binary_op);
+ PO;
+ }
+
OP(FILTER_OP_EQ_S64):
{
int res;
ret = -EINVAL;
goto end;
}
- estack_ax(stack, top)->u.s.seq_len = UINT_MAX;
- estack_ax(stack, top)->u.s.literal = 0;
+ estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 0;
dbg_printk("ref load string %s\n", estack_ax(stack, top)->u.s.str);
next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
PO;
ret = -EINVAL;
goto end;
}
- estack_ax(stack, top)->u.s.literal = 0;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 0;
next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
PO;
}
dbg_printk("load string %s\n", insn->data);
estack_push(stack, top, ax, bx);
estack_ax(stack, top)->u.s.str = insn->data;
- estack_ax(stack, top)->u.s.seq_len = UINT_MAX;
- estack_ax(stack, top)->u.s.literal = 1;
+ estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_PLAIN;
+ estack_ax(stack, top)->u.s.user = 0;
+ next_pc += sizeof(struct load_op) + strlen(insn->data) + 1;
+ PO;
+ }
+
+ OP(FILTER_OP_LOAD_STAR_GLOB_STRING):
+ {
+ struct load_op *insn = (struct load_op *) pc;
+
+ dbg_printk("load globbing pattern %s\n", insn->data);
+ estack_push(stack, top, ax, bx);
+ estack_ax(stack, top)->u.s.str = insn->data;
+ estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_STAR_GLOB;
+ estack_ax(stack, top)->u.s.user = 0;
next_pc += sizeof(struct load_op) + strlen(insn->data) + 1;
PO;
}
dbg_printk("get context ref offset %u type string\n",
ref->offset);
ctx_field = <tng_static_ctx->fields[ref->offset];
- ctx_field->get_value(ctx_field, &v);
+ ctx_field->get_value(ctx_field, lttng_probe_ctx, &v);
estack_push(stack, top, ax, bx);
estack_ax(stack, top)->u.s.str = v.str;
if (unlikely(!estack_ax(stack, top)->u.s.str)) {
ret = -EINVAL;
goto end;
}
- estack_ax(stack, top)->u.s.seq_len = UINT_MAX;
- estack_ax(stack, top)->u.s.literal = 0;
+ estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 0;
dbg_printk("ref get context string %s\n", estack_ax(stack, top)->u.s.str);
next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
PO;
dbg_printk("get context ref offset %u type s64\n",
ref->offset);
ctx_field = <tng_static_ctx->fields[ref->offset];
- ctx_field->get_value(ctx_field, &v);
+ ctx_field->get_value(ctx_field, lttng_probe_ctx, &v);
estack_push(stack, top, ax, bx);
estack_ax_v = v.s64;
dbg_printk("ref get context s64 %lld\n",
PO;
}
+ /* load userspace field ref */
+ OP(FILTER_OP_LOAD_FIELD_REF_USER_STRING):
+ {
+ struct load_op *insn = (struct load_op *) pc;
+ struct field_ref *ref = (struct field_ref *) insn->data;
+
+ dbg_printk("load field ref offset %u type user string\n",
+ ref->offset);
+ estack_push(stack, top, ax, bx);
+ estack_ax(stack, top)->u.s.user_str =
+ *(const char * const *) &filter_stack_data[ref->offset];
+ if (unlikely(!estack_ax(stack, top)->u.s.str)) {
+ dbg_printk("Filter warning: loading a NULL string.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ estack_ax(stack, top)->u.s.seq_len = LTTNG_SIZE_MAX;
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 1;
+ dbg_printk("ref load string %s\n", estack_ax(stack, top)->u.s.str);
+ next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
+ PO;
+ }
+
+ OP(FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE):
+ {
+ struct load_op *insn = (struct load_op *) pc;
+ struct field_ref *ref = (struct field_ref *) insn->data;
+
+ dbg_printk("load field ref offset %u type user sequence\n",
+ ref->offset);
+ estack_push(stack, top, ax, bx);
+ estack_ax(stack, top)->u.s.seq_len =
+ *(unsigned long *) &filter_stack_data[ref->offset];
+ estack_ax(stack, top)->u.s.user_str =
+ *(const char **) (&filter_stack_data[ref->offset
+ + sizeof(unsigned long)]);
+ if (unlikely(!estack_ax(stack, top)->u.s.str)) {
+ dbg_printk("Filter warning: loading a NULL sequence.\n");
+ ret = -EINVAL;
+ goto end;
+ }
+ estack_ax(stack, top)->u.s.literal_type =
+ ESTACK_STRING_LITERAL_TYPE_NONE;
+ estack_ax(stack, top)->u.s.user = 1;
+ next_pc += sizeof(struct load_op) + sizeof(struct field_ref);
+ PO;
+ }
+
END_OP
end:
/* return 0 (discard) on error */