constraint checking code
git-svn-id: https://asn1c.svn.sourceforge.net/svnroot/asn1c/trunk@149 59561ff5-6e30-0410-9f3c-9617f08c8826
diff --git a/libasn1compiler/asn1c_constraint.c b/libasn1compiler/asn1c_constraint.c
new file mode 100644
index 0000000..dd54224
--- /dev/null
+++ b/libasn1compiler/asn1c_constraint.c
@@ -0,0 +1,482 @@
+#include "asn1c_internal.h"
+#include "asn1c_constraint.h"
+
+#include <asn1fix_crange.h> /* constraint groker from libasn1fix */
+#include <asn1fix_export.h> /* other exportable stuff from libasn1fix */
+
+static int emit_alphabet_check_loop(arg_t *arg, asn1cnst_range_t *range);
+static int emit_value_determination_code(arg_t *arg, asn1p_expr_type_e etype);
+static int emit_size_determination_code(arg_t *arg, asn1p_expr_type_e etype);
+static asn1p_expr_type_e _find_terminal_type(arg_t *arg);
+static int emit_range_comparison_code(arg_t *arg, asn1cnst_range_t *range, const char *varname, asn1_integer_t natural_start, asn1_integer_t natural_stop);
+
+#define MKID(id) asn1c_make_identifier(0, (id), 0)
+
+static int global_compile_mark;
+
+int
+asn1c_emit_constraint_checking_code(arg_t *arg) {
+ asn1cnst_range_t *r_size;
+ asn1cnst_range_t *r_value;
+ asn1p_expr_t *expr = arg->expr;
+ asn1p_expr_type_e etype;
+ asn1p_constraint_t *ct;
+ int got_something = 0;
+
+ ct = expr->combined_constraints;
+ if(ct == NULL)
+ return 1; /* No additional constraints defined */
+
+ etype = _find_terminal_type(arg);
+
+ r_value=asn1constraint_compute_PER_range(etype, ct, ACT_EL_RANGE, 0, 0);
+ r_size = asn1constraint_compute_PER_range(etype, ct, ACT_CT_SIZE, 0, 0);
+ if(r_value) {
+ if(r_value->not_PER_visible
+ || r_value->extensible
+ || r_value->empty_constraint
+ || (r_value->left.type == ARE_MIN
+ && r_value->right.type == ARE_MAX)
+ || (etype == ASN_BASIC_BOOLEAN
+ && r_value->left.value == 0
+ && r_value->right.value == 1)
+ ) {
+ asn1constraint_range_free(r_value);
+ r_value = 0;
+ }
+ }
+ if(r_size) {
+ if(r_size->not_PER_visible
+ || r_size->extensible
+ || r_size->empty_constraint
+ || (r_size->left.value == 0 /* or .type == MIN */
+ && r_size->right.type == ARE_MAX)
+ ) {
+ asn1constraint_range_free(r_size);
+ r_size = 0;
+ }
+ }
+
+ OUT("const %s_t *st = sptr;\n", MKID(arg->expr->Identifier));
+
+ if(r_size || r_value) {
+ if(r_size) {
+ OUT("size_t size;\n");
+ }
+ if(r_value)
+ switch(etype) {
+ case ASN_BASIC_INTEGER:
+ case ASN_BASIC_ENUMERATED:
+ OUT("long value;\n");
+ break;
+ case ASN_BASIC_BOOLEAN:
+ OUT("int value;\n");
+ break;
+ default:
+ break;
+ }
+ }
+
+ OUT("\n");
+
+ /*
+ * Protection against null input.
+ */
+ OUT("if(!sptr) {\n");
+ INDENT(+1);
+ OUT("_ASN_ERRLOG(app_errlog, app_key,\n");
+ OUT("\t\"%%s: value not given\", td->name);\n");
+ OUT("return -1;\n");
+ INDENT(-1);
+ OUT("}\n");
+ OUT("\n");
+
+ if(r_value)
+ emit_value_determination_code(arg, etype);
+ if(r_size)
+ emit_size_determination_code(arg, etype);
+
+ /*
+ * Here is an if() {} else {} constaint checking code.
+ */
+ OUT("\n");
+ OUT("if(");
+ INDENT(+1);
+ if(r_size) {
+ if(got_something++) { OUT("\n"); OUT(" && "); }
+ OUT("(");
+ emit_range_comparison_code(arg, r_size, "size", 0, -1);
+ OUT(")");
+ }
+ if(r_value) {
+ if(got_something++) { OUT("\n"); OUT(" && "); }
+ OUT("(");
+ if(etype == ASN_BASIC_BOOLEAN)
+ emit_range_comparison_code(arg, r_value,
+ "value", 0, 1);
+ else
+ emit_range_comparison_code(arg, r_value,
+ "value", -1, -1);
+ OUT(")");
+ }
+ if(ct->_compile_mark) {
+ if(got_something++) { OUT("\n"); OUT(" && "); }
+ OUT("check_permitted_alphabet_%d(sptr)",
+ ct->_compile_mark);
+ }
+ if(!got_something) {
+ OUT("1 /* No applicable constraints whatsoever */");
+ }
+ INDENT(-1);
+ OUT(") {\n");
+ INDENT(+1);
+ OUT("/* Constraint check succeeded */\n");
+ OUT("return 1;\n");
+ INDENT(-1);
+ OUT("} else {\n");
+ INDENT(+1);
+ OUT("_ASN_ERRLOG(app_errlog, app_key,\n");
+ OUT("\t\"%%s: constraint failed\", td->name);\n");
+ OUT("return -1;\n");
+ INDENT(-1);
+ OUT("}\n");
+
+ return 0;
+}
+
+int
+asn1c_emit_constraint_tables(arg_t *arg, asn1p_constraint_t *ct) {
+ asn1_integer_t range_start;
+ asn1_integer_t range_stop;
+ asn1p_expr_type_e etype;
+ asn1cnst_range_t *range;
+ int table[256];
+ int use_table;
+
+ if(!ct) ct = arg->expr->combined_constraints;
+ if(!ct) return 0;
+
+ etype = _find_terminal_type(arg);
+
+ range = asn1constraint_compute_PER_range(etype, ct, ACT_CT_FROM, 0, 0);
+ if(!range) return 0;
+
+ if(range->not_PER_visible
+ || range->extensible
+ || range->empty_constraint) {
+ asn1constraint_range_free(range);
+ return 0;
+ }
+
+ range_start = range->left.value;
+ range_stop = range->right.value;
+ assert(range->left.type == ARE_VALUE);
+ assert(range->right.type == ARE_VALUE);
+ assert(range_start <= range_stop);
+
+ range_start = 0; /* Force old behavior */
+
+ /*
+ * Check if we need a test table to check the alphabet.
+ */
+ use_table = 1;
+ if((range_stop - range_start) > 255)
+ use_table = 0;
+ if(range->el_count == 0)
+ use_table = 0;
+
+ if(!ct->_compile_mark)
+ ct->_compile_mark = ++global_compile_mark;
+
+ if(use_table) {
+ int i, n = 0;
+ int untl;
+ memset(table, 0, sizeof(table));
+ for(i = -1; i < range->el_count; i++) {
+ asn1cnst_range_t *r;
+ asn1_integer_t v;
+ if(i == -1) {
+ if(range->el_count) continue;
+ r = range;
+ } else {
+ r = range->elements[i];
+ }
+ for(v = r->left.value; v <= r->right.value; v++) {
+ assert((v - range_start) >= 0);
+ assert((v - range_start) < 256);
+ table[v - range_start] = ++n;
+ }
+ }
+
+ OUT("static int permitted_alphabet_table_%d[256] = {\n",
+ ct->_compile_mark);
+ untl = (range_stop - range_start) + 1;
+ untl += (untl % 16)?16 - (untl % 16):0;
+ for(n = 0; n < untl; n++) {
+ OUT("%d,", table[n]?1:0);
+ if(!((n+1) % 16)) {
+ int c;
+ if(!n) {
+ OUT("\n");
+ continue;
+ }
+ OUT("\t/* ");
+ for(c = n - 15; c <= n; c++) {
+ if(table[c]) {
+ int a = c + range_start;
+ if(a > 0x20 && a < 0x80)
+ OUT("%c", a);
+ else
+ OUT(".");
+ } else {
+ OUT(" ");
+ }
+ }
+ OUT(" */");
+ OUT("\n");
+ }
+ }
+ OUT("};\n");
+ OUT("\n");
+ }
+
+ OUT("static int check_permitted_alphabet_%d(const void *sptr) {\n",
+ ct->_compile_mark);
+ INDENT(+1);
+ if(use_table) {
+ OUT("int *table = permitted_alphabet_table_%d;\n",
+ ct->_compile_mark);
+ emit_alphabet_check_loop(arg, 0);
+ } else {
+ emit_alphabet_check_loop(arg, range);
+ }
+ OUT("return 1;\n");
+ INDENT(-1);
+ OUT("}\n");
+ OUT("\n");
+
+ asn1constraint_range_free(range);
+
+ return 0;
+}
+
+static int
+emit_alphabet_check_loop(arg_t *arg, asn1cnst_range_t *range) {
+ asn1p_expr_type_e etype;
+ asn1_integer_t natural_stop;
+
+ etype = _find_terminal_type(arg);
+
+ OUT("/* The underlying type is %s */\n",
+ ASN_EXPR_TYPE2STR(etype));
+ OUT("const %s_t *st = sptr;\n", MKID(arg->expr->Identifier));
+
+ switch(etype) {
+ case ASN_STRING_UTF8String:
+ OUT("uint8_t *ch = st->buf;\n");
+ OUT("uint8_t *end = ch + st->size;\n");
+ OUT("\n");
+ OUT("for(; ch < end; ch++) {\n");
+ INDENT(+1);
+ OUT("uint8_t cv = *ch;\n");
+ if(!range) OUT("if(cv >= 0x80) return 0;\n");
+ natural_stop = 0xffffffffUL;
+ break;
+ case ASN_STRING_UniversalString:
+ OUT("uint32_t *ch = st->buf;\n");
+ OUT("uint32_t *end = ch + st->size;\n");
+ OUT("\n");
+ OUT("if(st->size % 4) return 0; /* (size%4)! */\n");
+ OUT("for(; ch < end; ch++) {\n");
+ INDENT(+1);
+ OUT("uint32_t cv = (((uint8_t *)ch)[0] << 24)\n");
+ OUT("\t\t| (((uint8_t *)ch)[1] << 16)\n");
+ OUT("\t\t| (((uint8_t *)ch)[2] << 8)\n");
+ OUT("\t\t| ((uint8_t *)ch)[3]\n");
+ if(!range) OUT("if(cv > 255) return 0;\n");
+ natural_stop = 0xffffffffUL;
+ break;
+ case ASN_STRING_BMPString:
+ OUT("uint16_t *ch = st->buf;\n");
+ OUT("uint16_t *end = ch + st->size;\n");
+ OUT("\n");
+ OUT("if(st->size % 2) return 0; /* (size%2)! */\n");
+ OUT("for(; ch < end; ch++) {\n");
+ INDENT(+1);
+ OUT("uint16_t cv = (((uint8_t *)ch)[0] << 8)\n");
+ OUT("\t\t| ((uint8_t *)ch)[1];\n");
+ if(!range) OUT("if(cv > 255) return 0;\n");
+ natural_stop = 0xffff;
+ break;
+ case ASN_BASIC_OCTET_STRING:
+ default:
+ OUT("uint8_t *ch = st->buf;\n");
+ OUT("uint8_t *end = ch + st->size;\n");
+ OUT("\n");
+ OUT("for(; ch < end; ch++) {\n");
+ INDENT(+1);
+ OUT("uint8_t cv = *ch;\n");
+ natural_stop = 0xff;
+ break;
+ }
+
+ if(range) {
+ OUT("if(!(");
+ emit_range_comparison_code(arg, range, "cv", 0, natural_stop);
+ OUT(")) return 0;\n");
+ } else {
+ OUT("if(!table[cv]) return 0;\n");
+ }
+
+ INDENT(-1);
+ OUT("}\n");
+
+ return 0;
+}
+
+static int
+emit_range_comparison_code(arg_t *arg, asn1cnst_range_t *range, const char *varname, asn1_integer_t natural_start, asn1_integer_t natural_stop) {
+ int ignore_left;
+ int ignore_right;
+ int i;
+
+ for(i = -1; i < range->el_count; i++) {
+ asn1cnst_range_t *r;
+ if(i == -1) {
+ if(range->el_count) continue;
+ r = range;
+ } else {
+ if(i) OUT(" || ");
+ r = range->elements[i];
+ }
+
+ if(r != range) OUT("(");
+
+ ignore_left = (r->left.type == ARE_MIN)
+ || (natural_start != -1
+ && r->left.value <= natural_start);
+ ignore_right = (r->right.type == ARE_MAX)
+ || (natural_stop != -1
+ && r->right.value >= natural_stop);
+ if(ignore_left && ignore_right) {
+ OUT("1 /* Constraint matches natural range of %s */",
+ varname);
+ continue;
+ }
+
+ if(ignore_left) {
+ OUT("%s <= %lld", varname,
+ (long long)r->right.value);
+ } else if(ignore_right) {
+ OUT("%s >= %lld", varname,
+ (long long)r->left.value);
+ } else if(r->left.value == r->right.value) {
+ OUT("%s == %lld", varname,
+ (long long)r->right.value);
+ } else {
+ OUT("%s >= %lld && %s <= %lld",
+ varname,
+ (long long)r->left.value,
+ varname,
+ (long long)r->right.value);
+ }
+ if(r != range) OUT(")");
+ }
+
+ return 0;
+}
+
+static int
+emit_size_determination_code(arg_t *arg, asn1p_expr_type_e etype) {
+
+ switch(etype) {
+ case ASN_BASIC_BIT_STRING:
+ OUT("if(st->size > 0) {\n");
+ OUT("\t/* Size in bits */\n");
+ OUT("\tsize = (st->size - 1) - (st->buf[0] & 0x7);\n");
+ OUT("} else {\n");
+ OUT("\tsize = 0;\n");
+ OUT("}\n");
+ break;
+ case ASN_STRING_UniversalString:
+ OUT("size = st->size >> 2;\t/* 4 byte per character */\n");
+ break;
+ case ASN_STRING_BMPString:
+ OUT("size = st->size >> 1;\t/* 2 byte per character */\n");
+ break;
+ case ASN_STRING_UTF8String:
+ OUT("size = UTF8String_length(st, td->name, app_errlog, app_key);\n");
+ OUT("if(size == (size_t)-1) return -1;\n");
+ break;
+ case ASN_CONSTR_SET_OF:
+ case ASN_CONSTR_SEQUENCE_OF:
+ OUT("{ /* Determine the number of elements */\n");
+ INDENT(+1);
+ OUT("A_%s_OF(void) *list;\n",
+ etype==ASN_CONSTR_SET_OF?"SET":"SEQUENCE");
+ OUT("(void *)list = st;\n");
+ OUT("size = list->count;\n");
+ INDENT(-1);
+ OUT("}\n");
+ break;
+ default:
+ if((etype & ASN_STRING_MASK)
+ || etype == ASN_BASIC_OCTET_STRING) {
+ OUT("size = st->size;\n");
+ break;
+ } else {
+ const char *type_name = ASN_EXPR_TYPE2STR(etype);
+ if(!type_name) type_name = arg->expr->Identifier;
+ WARNING("SizeConstraint is not defined for %s",
+ type_name);
+ OUT_NOINDENT("#warning SizeConstraint "
+ "is not defined for %s!\n", type_name);
+ OUT("size = st->size;\n");
+ }
+ return -1;
+ }
+
+ return 0;
+}
+
+static int
+emit_value_determination_code(arg_t *arg, asn1p_expr_type_e etype) {
+
+ switch(etype) {
+ case ASN_BASIC_INTEGER:
+ case ASN_BASIC_ENUMERATED:
+ if(arg->flags & A1C_USE_NATIVE_INTEGERS) {
+ OUT("value = *(int *)st;\n");
+ } else {
+ OUT("if(asn1_INTEGER2long(st, &value)) {\n");
+ INDENT(+1);
+ OUT("_ASN_ERRLOG(app_errlog, app_key,\n");
+ OUT("\t\"%%s: value too large\", td->name);\n");
+ OUT("return -1;\n");
+ INDENT(-1);
+ OUT("}\n");
+ }
+ break;
+ case ASN_BASIC_BOOLEAN:
+ OUT("value = (*(int *)st) ? 1 : 0;\n");
+ break;
+ default:
+ WARNING("Value cannot be determined "
+ "for constraint check for %s at line %d\n",
+ arg->expr->Identifier, arg->expr->_lineno);
+ OUT("#error Value cannot be determined for %s at %d\n",
+ arg->expr->Identifier, arg->expr->_lineno);
+ break;
+ }
+
+ return 0;
+}
+
+static asn1p_expr_type_e
+_find_terminal_type(arg_t *arg) {
+ asn1p_expr_t *expr;
+ expr = asn1f_find_terminal_type_ex(arg->asn, arg->mod, arg->expr, NULL);
+ if(expr) return expr->expr_type;
+ return A1TC_INVALID;
+}
+