diff options
Diffstat (limited to 'dfilter-grammar.y')
| -rw-r--r-- | dfilter-grammar.y | 166 |
1 files changed, 164 insertions, 2 deletions
diff --git a/dfilter-grammar.y b/dfilter-grammar.y index b49ac0b9ff..9a966985d0 100644 --- a/dfilter-grammar.y +++ b/dfilter-grammar.y @@ -3,7 +3,7 @@ /* dfilter-grammar.y * Parser for display filters * - * $Id: dfilter-grammar.y,v 1.25 1999/10/11 19:39:29 guy Exp $ + * $Id: dfilter-grammar.y,v 1.26 1999/10/12 04:21:09 gram Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs <gerald@zing.org> @@ -93,6 +93,13 @@ static GNode* dfilter_mknode_bytes_variable(gint id, gint offset, guint length); static guint32 string_to_value(char *s); static int ether_str_to_guint8_array(const char *s, guint8 *mac); static int ipv6_str_to_guint8_array(const char *s, guint8 *ipv6); +static guint dfilter_get_bytes_variable_offset(GNode *gnode); +static guint dfilter_get_bytes_value_length(GNode* gnode); +static void dfilter_set_bytes_variable_length(GNode *gnode, guint length); +static guint dfilter_get_bytes_variable_length(GNode *gnode); +static gint dfilter_get_bytes_variable_field_registered_length(GNode *gnode); +static char* dfilter_get_variable_abbrev(GNode *gnode); +static int check_bytes_variable_sanity(GNode *gnode); /* This is the dfilter we're currently processing. It's how * dfilter_compile communicates with us. @@ -223,10 +230,56 @@ relation: numeric_variable numeric_relation numeric_value | bytes_variable bytes_relation bytes_value { + int a_len, b_len; + + a_len = dfilter_get_bytes_variable_length($1); + b_len = dfilter_get_bytes_value_length($3); + + if (a_len == 0) { + dfilter_set_bytes_variable_length($1, b_len); + a_len = b_len; + } + + if (!check_bytes_variable_sanity($1)) { + YYERROR; + } + + if (a_len != b_len) { + dfilter_fail("Field \"%s\" has %u byte%s being compared, but %u byte%s " + "were supplied.", + dfilter_get_variable_abbrev($1), + a_len, plurality(a_len, "", "s"), + b_len, plurality(b_len, "", "s")); + YYERROR; + } + $$ = dfilter_mknode_join($1, relation, $2, $3); } | bytes_variable bytes_relation bytes_variable { + int a_len, b_len; + + a_len = dfilter_get_bytes_variable_length($1); + b_len = dfilter_get_bytes_variable_length($3); + + if (!check_bytes_variable_sanity($1)) { + YYERROR; + } + + if (!check_bytes_variable_sanity($3)) { + YYERROR; + } + + if (a_len != b_len) { + dfilter_fail("Fields \"%s\" and \"%s\" are being compared with " + "disparate lengths of %u byte%s and %u byte%s.", + dfilter_get_variable_abbrev($1), + dfilter_get_variable_abbrev($3), + a_len, plurality(a_len, "", "s"), + b_len, plurality(b_len, "", "s")); + YYERROR; + } + $$ = dfilter_mknode_join($1, relation, $2, $3); } @@ -304,8 +357,27 @@ bytes_value: T_VAL_BYTE_STRING $$ = dfilter_mknode_bytes_value(barray); g_free($1); } - ; + | T_VAL_NUMBER_STRING + { + guint32 val32 = string_to_value($1); + guint8 val8; + GByteArray *barray; + + if (val32 > 0xff) { + dfilter_fail("The value \"%s\" cannot be stored in a single-byte byte-string. " + "Use the multi-byte \"xx:yy\" representation.", $1); + YYERROR; + } + val8 = (guint8) val32; + barray = g_byte_array_new(); + global_df->list_of_byte_arrays = g_slist_append(global_df->list_of_byte_arrays, barray); + g_byte_array_append(barray, &val8, 1); + + $$ = dfilter_mknode_bytes_value(barray); + g_free($1); + } + ; numeric_variable: T_FT_UINT8 { $$ = dfilter_mknode_numeric_variable($1.id); } | T_FT_UINT16 { $$ = dfilter_mknode_numeric_variable($1.id); } @@ -532,6 +604,62 @@ dfilter_mknode_bytes_variable(gint id, gint offset, guint length) return gnode; } +/* Gets length of variable represented by node from proto_register */ +static gint +dfilter_get_bytes_variable_field_registered_length(GNode *gnode) +{ + dfilter_node *node = gnode->data; + + /* Is this really a bytes_variable? */ + g_assert(node->fill_array_func = fill_array_bytes_variable); + + return proto_registrar_get_length(node->value.variable); +} + +/* Sets the length of a bytes_variable node */ +static void +dfilter_set_bytes_variable_length(GNode *gnode, guint length) +{ + dfilter_node *node = gnode->data; + + /* Is this really a bytes_variable? */ + g_assert(node->fill_array_func = fill_array_bytes_variable); + + node->length = length; +} + +/* Gets the length of a bytes_variable node */ +static guint +dfilter_get_bytes_variable_length(GNode *gnode) +{ + dfilter_node *node = gnode->data; + + /* Is this really a bytes_variable? */ + g_assert(node->fill_array_func = fill_array_bytes_variable); + + return node->length; +} + +/* Gets the offset of a bytes_variable node */ +static guint +dfilter_get_bytes_variable_offset(GNode *gnode) +{ + dfilter_node *node = gnode->data; + + /* Is this really a bytes_variable? */ + g_assert(node->fill_array_func = fill_array_bytes_variable); + + return node->offset; +} + +static char* +dfilter_get_variable_abbrev(GNode *gnode) +{ + dfilter_node *node = gnode->data; + + return proto_registrar_get_abbrev(node->value.variable); +} + static GNode* dfilter_mknode_numeric_value(guint32 val) { @@ -664,6 +792,17 @@ dfilter_mknode_bytes_value(GByteArray *barray) return gnode; } +/* Given a node representing a bytes_value, returns + * the length of the byte array */ +static guint +dfilter_get_bytes_value_length(GNode* gnode) +{ + dfilter_node *node = gnode->data; + + g_assert(node->ntype == bytes); + return node->length; +} + static guint32 string_to_value(char *s) { @@ -764,3 +903,26 @@ ipv6_str_to_guint8_array(const char *s, guint8 *ipv6) return 1; /* read exactly 16 hex pairs */ } + +static int +check_bytes_variable_sanity(GNode *gnode) +{ + int a_off, a_len, reg_len, t_off; + + a_off = dfilter_get_bytes_variable_offset(gnode); + a_len = dfilter_get_bytes_variable_length(gnode); + reg_len = dfilter_get_bytes_variable_field_registered_length(gnode); + + if (reg_len > 0) { + t_off = a_off >= 0 ? a_off : reg_len + a_off; + if (t_off + a_len > reg_len) { + dfilter_fail("The \"%s\" field is only %u byte%s wide, but " + "%u byte%s were supplied.", + dfilter_get_variable_abbrev(gnode), + reg_len, plurality(reg_len, "", "s"), + a_len, plurality(a_len, "", "s")); + return 0; + } + } + return 1; +} |