Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 520 insertions, 0 deletions

diff --git a/epan/dfilter/dfunctions.c b/epan/dfilter/dfunctions.c
new file mode 100644
index 0000000..be36424
--- /dev/null
+++ b/epan/dfilter/dfunctions.c
@@ -0,0 +1,520 @@
+/*
+ * Wireshark - Network traffic analyzer
+ *
+ * Copyright 2006 Gilbert Ramirez <gram@alumni.rice.edu>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+#define WS_LOG_DOMAIN LOG_DOMAIN_DFILTER
+
+#include <glib.h>
+
+#include "dfilter-int.h"
+#include "dfunctions.h"
+#include "sttype-field.h"
+#include "semcheck.h"
+
+#include <string.h>
+
+#include <ftypes/ftypes.h>
+#include <epan/exceptions.h>
+#include <wsutil/ws_assert.h>
+
+#define FAIL(dfw, node, ...) \
+    do { \
+        ws_noisy("Semantic check failed here."); \
+        dfilter_fail_throw(dfw, DF_ERROR_GENERIC, stnode_location(node), __VA_ARGS__); \
+    } while (0)
+
+/* Convert an FT_STRING using a callback function */
+static bool
+string_walk(GSList *stack, uint32_t arg_count _U_, df_cell_t *retval, char(*conv_func)(char))
+{
+    GPtrArray   *arg1;
+    fvalue_t    *arg_fvalue;
+    fvalue_t    *new_ft_string;
+    const wmem_strbuf_t *src;
+    wmem_strbuf_t       *dst;
+
+    ws_assert(arg_count == 1);
+    arg1 = stack->data;
+    if (arg1 == NULL)
+        return false;
+
+    for (unsigned i = 0; i < arg1->len; i++) {
+        arg_fvalue = arg1->pdata[i];
+        /* XXX - it would be nice to handle FT_TVBUFF, too */
+        if (FT_IS_STRING(fvalue_type_ftenum(arg_fvalue))) {
+            src = fvalue_get_strbuf(arg_fvalue);
+            dst = wmem_strbuf_new_sized(NULL, src->len);
+            for (size_t j = 0; j < src->len; j++) {
+                    wmem_strbuf_append_c(dst, conv_func(src->str[j]));
+            }
+            new_ft_string = fvalue_new(FT_STRING);
+            fvalue_set_strbuf(new_ft_string, dst);
+            df_cell_append(retval, new_ft_string);
+        }
+    }
+
+    return true;
+}
+
+/* dfilter function: lower() */
+static bool
+df_func_lower(GSList *stack, uint32_t arg_count, df_cell_t *retval)
+{
+    return string_walk(stack, arg_count, retval, g_ascii_tolower);
+}
+
+/* dfilter function: upper() */
+static bool
+df_func_upper(GSList *stack, uint32_t arg_count, df_cell_t *retval)
+{
+    return string_walk(stack, arg_count, retval, g_ascii_toupper);
+}
+
+/* dfilter function: count() */
+static bool
+df_func_count(GSList *stack, uint32_t arg_count _U_, df_cell_t *retval)
+{
+    GPtrArray *arg1;
+    fvalue_t *ft_ret;
+    uint32_t  num_items;
+
+    ws_assert(arg_count == 1);
+    arg1 = stack->data;
+    if (arg1 == NULL)
+        return false;
+
+    num_items = arg1->len;
+    ft_ret = fvalue_new(FT_UINT32);
+    fvalue_set_uinteger(ft_ret, num_items);
+    df_cell_append(retval, ft_ret);
+
+    return true;
+}
+
+/* dfilter function: string() */
+static bool
+df_func_string(GSList *stack, uint32_t arg_count _U_, df_cell_t *retval)
+{
+    GPtrArray *arg1;
+    fvalue_t *arg_fvalue;
+    fvalue_t *new_ft_string;
+    char     *s;
+
+    ws_assert(arg_count == 1);
+    arg1 = stack->data;
+    if (arg1 == NULL)
+        return false;
+
+    for (unsigned i = 0; i < arg1->len; i++) {
+        arg_fvalue = arg1->pdata[i];
+        switch (fvalue_type_ftenum(arg_fvalue))
+        {
+        case FT_UINT8:
+        case FT_UINT16:
+        case FT_UINT24:
+        case FT_UINT32:
+        case FT_UINT40:
+        case FT_UINT48:
+        case FT_UINT56:
+        case FT_UINT64:
+        case FT_INT8:
+        case FT_INT16:
+        case FT_INT32:
+        case FT_INT40:
+        case FT_INT48:
+        case FT_INT56:
+        case FT_INT64:
+        case FT_IPv4:
+        case FT_IPv6:
+        case FT_FLOAT:
+        case FT_DOUBLE:
+        case FT_ETHER:
+        case FT_FRAMENUM:
+        case FT_AX25:
+        case FT_IPXNET:
+        case FT_GUID:
+        case FT_OID:
+        case FT_EUI64:
+        case FT_VINES:
+        case FT_REL_OID:
+        case FT_SYSTEM_ID:
+        case FT_FCWWN:
+        case FT_IEEE_11073_SFLOAT:
+        case FT_IEEE_11073_FLOAT:
+            s = fvalue_to_string_repr(NULL, arg_fvalue, FTREPR_DFILTER, BASE_NONE);
+            /* Ensure we have an allocated string here */
+            if (!s)
+                s = wmem_strdup(NULL, "");
+            break;
+        default:
+            return true;
+        }
+
+        new_ft_string = fvalue_new(FT_STRING);
+        fvalue_set_string(new_ft_string, s);
+        wmem_free(NULL, s);
+        df_cell_append(retval, new_ft_string);
+    }
+
+    return true;
+}
+
+static bool
+df_func_compare(GSList *stack, uint32_t arg_count, df_cell_t *retval,
+                    bool (*fv_cmp)(const fvalue_t *a, const fvalue_t *b))
+{
+    fvalue_t *fv_ret = NULL;
+    GSList   *args;
+    GPtrArray *arg1;
+    fvalue_t *arg_fvalue;
+    uint32_t i;
+
+    for (args = stack, i = 0; i < arg_count; args = args->next, i++) {
+        arg1 = args->data;
+        for (unsigned j = 0; j < arg1->len; j++) {
+            arg_fvalue = arg1->pdata[j];
+            if (fv_ret == NULL || fv_cmp(arg_fvalue, fv_ret)) {
+                fv_ret = arg_fvalue;
+            }
+        }
+    }
+
+    if (fv_ret == NULL)
+        return false;
+
+    df_cell_append(retval, fvalue_dup(fv_ret));
+
+    return true;
+}
+
+/* Find maximum value. */
+static bool
+df_func_max(GSList *stack, uint32_t arg_count, df_cell_t *retval)
+{
+    return df_func_compare(stack, arg_count, retval, fvalue_gt);
+}
+
+/* Find minimum value. */
+static bool
+df_func_min(GSList *stack, uint32_t arg_count, df_cell_t *retval)
+{
+    return df_func_compare(stack, arg_count, retval, fvalue_lt);
+}
+
+static bool
+df_func_abs(GSList *stack, uint32_t arg_count _U_, df_cell_t *retval)
+{
+    GPtrArray *arg1;
+    fvalue_t *fv_arg, *new_fv;
+    char     *err_msg = NULL;
+
+    ws_assert(arg_count == 1);
+    arg1 = stack->data;
+    if (arg1 == NULL)
+        return false;
+
+    for (unsigned i = 0; i < arg1->len; i++) {
+        fv_arg = arg1->pdata[i];
+        if (fvalue_is_negative(fv_arg)) {
+            new_fv = fvalue_unary_minus(fv_arg, &err_msg);
+            if (new_fv == NULL) {
+                ws_debug("abs: %s", err_msg);
+                g_free(err_msg);
+                err_msg = NULL;
+            }
+        }
+        else {
+            new_fv = fvalue_dup(fv_arg);
+        }
+        df_cell_append(retval, new_fv);
+    }
+
+    return !df_cell_is_empty(retval);
+}
+
+/* For upper() and lower() checks that the parameter passed to
+ * it is an FT_STRING */
+static ftenum_t
+ul_semcheck_is_field_string(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype _U_,
+                            GSList *param_list, df_loc_t func_loc _U_)
+{
+    header_field_info *hfinfo;
+
+    ws_assert(g_slist_length(param_list) == 1);
+    stnode_t *st_node = param_list->data;
+
+    if (stnode_type_id(st_node) == STTYPE_FIELD) {
+        dfw->field_count++;
+        hfinfo = sttype_field_hfinfo(st_node);
+        if (FT_IS_STRING(hfinfo->type)) {
+            return FT_STRING;
+        }
+    }
+    FAIL(dfw, st_node, "Only string type fields can be used as parameter for %s()", func_name);
+}
+
+static ftenum_t
+ul_semcheck_is_field(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype _U_,
+                            GSList *param_list, df_loc_t func_loc _U_)
+{
+    ws_assert(g_slist_length(param_list) == 1);
+    stnode_t *st_node = param_list->data;
+
+    if (stnode_type_id(st_node) == STTYPE_FIELD) {
+        dfw->field_count++;
+        return FT_UINT32;
+    }
+
+    FAIL(dfw, st_node, "Only fields can be used as parameter for %s()", func_name);
+}
+
+static ftenum_t
+ul_semcheck_can_length(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype,
+                            GSList *param_list, df_loc_t func_loc)
+{
+    ws_assert(g_slist_length(param_list) == 1);
+    stnode_t *st_node = param_list->data;
+
+    ul_semcheck_is_field(dfw, func_name, lhs_ftype, param_list, func_loc);
+    if (!ftype_can_length(sttype_field_ftenum(st_node))) {
+        FAIL(dfw, st_node, "Field %s does not support the %s() function", stnode_todisplay(st_node), func_name);
+    }
+    return FT_UINT32;
+}
+
+static ftenum_t
+ul_semcheck_string_param(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype _U_,
+                            GSList *param_list, df_loc_t func_loc _U_)
+{
+    header_field_info *hfinfo;
+
+    ws_assert(g_slist_length(param_list) == 1);
+    stnode_t *st_node = param_list->data;
+
+    if (stnode_type_id(st_node) == STTYPE_FIELD) {
+        dfw->field_count++;
+        hfinfo = sttype_field_hfinfo(st_node);
+        switch (hfinfo->type) {
+            case FT_UINT8:
+            case FT_UINT16:
+            case FT_UINT24:
+            case FT_UINT32:
+            case FT_UINT40:
+            case FT_UINT48:
+            case FT_UINT56:
+            case FT_UINT64:
+            case FT_INT8:
+            case FT_INT16:
+            case FT_INT32:
+            case FT_INT40:
+            case FT_INT48:
+            case FT_INT56:
+            case FT_INT64:
+            case FT_IPv4:
+            case FT_IPv6:
+            case FT_FLOAT:
+            case FT_DOUBLE:
+            case FT_ETHER:
+            case FT_FRAMENUM:
+            case FT_AX25:
+            case FT_IPXNET:
+            case FT_GUID:
+            case FT_OID:
+            case FT_EUI64:
+            case FT_VINES:
+            case FT_REL_OID:
+            case FT_SYSTEM_ID:
+            case FT_FCWWN:
+            case FT_IEEE_11073_SFLOAT:
+            case FT_IEEE_11073_FLOAT:
+                return FT_STRING;
+            default:
+                break;
+        }
+        FAIL(dfw, st_node, "String conversion for field \"%s\" is not supported", hfinfo->abbrev);
+    }
+    FAIL(dfw, st_node, "Only fields can be used as parameter for %s()", func_name);
+}
+
+/* Check arguments are all the same type and they can be compared. */
+/*
+  Every STTYPE_LITERAL needs to be resolved to a STTYPE_FVALUE. If we don't
+  have type information (lhs_ftype is FT_NONE) and we have not seen an argument
+  with a definite type we defer resolving literals to values until we have examined
+  the entire list of function arguments. If we still cannot resolve to a definite
+  type after that (all arguments must have the same type) then we give up and
+  return FT_NONE.
+*/
+static ftenum_t
+ul_semcheck_compare(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype,
+                        GSList *param_list, df_loc_t func_loc _U_)
+{
+    stnode_t *arg;
+    sttype_id_t type;
+    ftenum_t ftype, ft_arg;
+    GSList *l;
+    fvalue_t *fv;
+    wmem_list_t *literals = NULL;
+
+    ftype = lhs_ftype;
+
+    for (l = param_list; l != NULL; l = l->next) {
+        arg = l->data;
+        type = stnode_type_id(arg);
+
+        if (type == STTYPE_ARITHMETIC) {
+            ft_arg = check_arithmetic(dfw, arg, ftype);
+        }
+        else if (type == STTYPE_LITERAL) {
+            if (ftype != FT_NONE) {
+                fv = dfilter_fvalue_from_literal(dfw, ftype, arg, false, NULL);
+                stnode_replace(arg, STTYPE_FVALUE, fv);
+                ft_arg = fvalue_type_ftenum(fv);
+            }
+            else {
+                if (literals == NULL) {
+                    literals = wmem_list_new(dfw->dfw_scope);
+                }
+                wmem_list_append(literals, arg);
+                ft_arg = FT_NONE;
+            }
+        }
+        else if (type == STTYPE_FUNCTION) {
+            ft_arg = check_function(dfw, arg, ftype);
+        }
+        else if (type == STTYPE_FIELD) {
+            dfw->field_count++;
+            ft_arg = sttype_field_ftenum(arg);
+        }
+        else if (type == STTYPE_REFERENCE) {
+            ft_arg = sttype_field_ftenum(arg);
+        }
+        else {
+            FAIL(dfw, arg, "Argument '%s' is not valid for %s()",
+                                    stnode_todisplay(arg), func_name);
+        }
+
+        if (ftype == FT_NONE) {
+            ftype = ft_arg;
+        }
+        if (ft_arg != FT_NONE && ftype != FT_NONE && !compatible_ftypes(ft_arg, ftype)) {
+            FAIL(dfw, arg, "Arguments to '%s' must be type compatible (expected %s, got %s)",
+                                        func_name, ftype_name(ftype), ftype_name(ft_arg));
+        }
+        if (ft_arg != FT_NONE && !ftype_can_cmp(ft_arg)) {
+            FAIL(dfw, arg, "Argument '%s' to '%s' cannot be ordered",
+                                    stnode_todisplay(arg), func_name);
+        }
+    }
+
+    if (literals != NULL) {
+        if (ftype != FT_NONE) {
+            wmem_list_frame_t *fp;
+            stnode_t *st;
+            for (fp = wmem_list_head(literals); fp != NULL; fp = wmem_list_frame_next(fp)) {
+                st = wmem_list_frame_data(fp);
+                fv = dfilter_fvalue_from_literal(dfw, ftype, st, false, NULL);
+                stnode_replace(st, STTYPE_FVALUE, fv);
+            }
+        }
+        wmem_destroy_list(literals);
+    }
+
+    return ftype;
+}
+
+static ftenum_t
+ul_semcheck_absolute_value(dfwork_t *dfw, const char *func_name, ftenum_t lhs_ftype,
+                        GSList *param_list, df_loc_t func_loc _U_)
+{
+    ws_assert(g_slist_length(param_list) == 1);
+    stnode_t *st_node;
+    ftenum_t ftype;
+    fvalue_t *fv;
+
+    st_node = param_list->data;
+
+    if (stnode_type_id(st_node) == STTYPE_ARITHMETIC) {
+        ftype = check_arithmetic(dfw, st_node, lhs_ftype);
+    }
+    else if (stnode_type_id(st_node) == STTYPE_LITERAL) {
+        if (lhs_ftype != FT_NONE) {
+            /* Convert RHS literal to the same ftype as LHS. */
+            fv = dfilter_fvalue_from_literal(dfw, lhs_ftype, st_node, false, NULL);
+            stnode_replace(st_node, STTYPE_FVALUE, fv);
+            ftype = fvalue_type_ftenum(fv);
+        }
+        else {
+            FAIL(dfw, st_node, "Need a field or field-like value on the LHS.");
+        }
+    }
+    else if (stnode_type_id(st_node) == STTYPE_FUNCTION) {
+        ftype = check_function(dfw, st_node, lhs_ftype);
+    }
+    else if (stnode_type_id(st_node) == STTYPE_FIELD) {
+        dfw->field_count++;
+        ftype = sttype_field_ftenum(st_node);
+    }
+    else {
+        ftype = FT_NONE;
+    }
+
+    if (ftype == FT_NONE) {
+        FAIL(dfw, st_node, "Type %s is not valid for %s",
+                        stnode_type_name(st_node), func_name);
+    }
+    if (!ftype_can_is_negative(ftype)) {
+        FAIL(dfw, st_node, "'%s' is not a valid argument to '%s'()",
+                        stnode_todisplay(st_node), func_name);
+    }
+    return ftype;
+}
+
+/* The table of all display-filter functions */
+static df_func_def_t
+df_functions[] = {
+    { "lower",  df_func_lower,  1, 1, ul_semcheck_is_field_string },
+    { "upper",  df_func_upper,  1, 1, ul_semcheck_is_field_string },
+    /* Length function is implemented as a DFVM instruction. */
+    { "len",    NULL,           1, 1, ul_semcheck_can_length },
+    { "count",  df_func_count,  1, 1, ul_semcheck_is_field },
+    { "string", df_func_string, 1, 1, ul_semcheck_string_param },
+    { "max",    df_func_max,    1, 0, ul_semcheck_compare },
+    { "min",    df_func_min,    1, 0, ul_semcheck_compare },
+    { "abs",    df_func_abs,    1, 1, ul_semcheck_absolute_value },
+    { NULL, NULL, 0, 0, NULL }
+};
+
+/* Lookup a display filter function record by name */
+df_func_def_t*
+df_func_lookup(const char *name)
+{
+    df_func_def_t *func_def;
+
+    func_def = df_functions;
+    while (func_def->name != NULL) {
+        if (strcmp(func_def->name, name) == 0) {
+            return func_def;
+        }
+        func_def++;
+    }
+    return NULL;
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */