diff options
Diffstat (limited to 'rdns_scan/zmap4rdns/src/expression.c')
| -rw-r--r-- | rdns_scan/zmap4rdns/src/expression.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/rdns_scan/zmap4rdns/src/expression.c b/rdns_scan/zmap4rdns/src/expression.c new file mode 100644 index 0000000..12ccd61 --- /dev/null +++ b/rdns_scan/zmap4rdns/src/expression.c @@ -0,0 +1,170 @@ +/* + * ZMap Copyright 2013 Regents of the University of Michigan + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may not + * use this file except in compliance with the License. You may obtain a copy + * of the License at http://www.apache.org/licenses/LICENSE-2.0 + */ + +#include "expression.h" +#include "fieldset.h" + +#include "../lib/xalloc.h" + +/* Static helper functions */ + +static node_t *alloc_node(); +static int eval_gt_node(node_t *node, fieldset_t *fields); +static int eval_lt_node(node_t *node, fieldset_t *fields); +static int eval_eq_node(node_t *node, fieldset_t *fields); +static int eval_lt_eq_node(node_t *node, fieldset_t *fields); +static int eval_gt_eq_node(node_t *node, fieldset_t *fields); + +static node_t *alloc_node() +{ + node_t *node = xmalloc(sizeof(node_t)); + return node; +} + +static int eval_gt_node(node_t *node, fieldset_t *fields) +{ + int index = node->left_child->value.field.index; + uint64_t expected = node->right_child->value.int_literal; + uint64_t actual = fs_get_uint64_by_index(fields, index); + return (actual > expected); +} + +static int eval_lt_node(node_t *node, fieldset_t *fields) +{ + int index = node->left_child->value.field.index; + uint64_t expected = node->right_child->value.int_literal; + uint64_t actual = fs_get_uint64_by_index(fields, index); + return (actual < expected); +} + +static int eval_eq_node(node_t *node, fieldset_t *fields) +{ + node_t *literal = node->right_child; + int index = node->left_child->value.field.index; + char *expected, *actual; + switch (literal->type) { + case STRING: + expected = literal->value.string_literal; + actual = fs_get_string_by_index(fields, index); + return (strcmp(expected, actual) == 0); + break; + case INT: + return (fs_get_uint64_by_index(fields, index) == + literal->value.int_literal); + break; + default: + printf("wat\n"); + break; + } + return 0; +} + +static int eval_lt_eq_node(node_t *node, fieldset_t *fields) +{ + return !(eval_gt_node(node, fields)); +} + +static int eval_gt_eq_node(node_t *node, fieldset_t *fields) +{ + return !(eval_lt_node(node, fields)); +} + +/* Exposed functions */ + +node_t *make_op_node(enum operation op) +{ + node_t *node = alloc_node(); + node->type = OP; + node->value.op = op; + return node; +} + +node_t *make_field_node(char *fieldname) +{ + node_t *node = alloc_node(); + node->type = FIELD; + node->value.field.fieldname = fieldname; + return node; +} + +node_t *make_string_node(char *literal) +{ + node_t *node = alloc_node(); + node->type = STRING; + node->value.string_literal = literal; + return node; +} + +node_t *make_int_node(int literal) +{ + node_t *node = alloc_node(); + node->type = INT; + node->value.int_literal = literal; + return node; +} + +int evaluate_expression(node_t *root, fieldset_t *fields) +{ + if (!root) + return 1; + switch (root->type) { /* XXX Not sure if runs */ + case FIELD: + case STRING: + case INT: + return 1; + case OP: + break; + } + switch (root->value.op) { + case GT: + return eval_gt_node(root, fields); + case LT: + return eval_lt_node(root, fields); + case EQ: + return eval_eq_node(root, fields); + case NEQ: + return (!eval_eq_node(root, fields)); + case LT_EQ: + return eval_lt_eq_node(root, fields); + case GT_EQ: + return eval_gt_eq_node(root, fields); + case AND: + return (evaluate_expression(root->left_child, fields) && + evaluate_expression(root->right_child, fields)); + case OR: + return (evaluate_expression(root->left_child, fields) || + evaluate_expression(root->right_child, fields)); + } + return 0; +} + +void print_expression(node_t *root) +{ + if (!root) + return; + printf("%s", "( "); + print_expression(root->left_child); + switch (root->type) { + case OP: + printf(" %i ", root->value.op); + break; + case FIELD: + printf(" (%s", root->value.field.fieldname); + break; + case STRING: + printf("%s) ", root->value.string_literal); + break; + case INT: + printf(" %llu) ", (long long unsigned)root->value.int_literal); + break; + default: + break; + } + print_expression(root->right_child); + printf("%s", " )"); +} |