/* * Filters: Instructions themselves * * Copyright 1998 Pavel Machek * Copyright 2018 Maria Matejka * Copyright 2018 CZ.NIC z.s.p.o. * * Can be freely distributed and used under the terms of the GNU GPL. * * The filter code goes through several phases: * * 1 Parsing * Flex- and Bison-generated parser decodes the human-readable data into * a struct f_inst tree. This is an infix tree that was interpreted by * depth-first search execution in previous versions of the interpreter. * All instructions have their constructor: f_new_inst(FI_EXAMPLE, ...) * translates into f_new_inst_FI_EXAMPLE(...) and the types are checked in * compile time. If the result of the instruction is always the same, * it's reduced to FI_CONSTANT directly in constructor. This phase also * counts how many instructions are underlying in means of f_line_item * fields to know how much we have to allocate in the next phase. * * 2 Linearize before interpreting * The infix tree is always interpreted in the same order. Therefore we * sort the instructions one after another into struct f_line. Results * and arguments of these instructions are implicitly put on a value * stack; e.g. the + operation just takes two arguments from the value * stack and puts the result on there. * * 3 Interpret * The given line is put on a custom execution stack. If needed (FI_CALL, * FI_SWITCH, FI_AND, FI_OR, FI_CONDITION, ...), another line is put on top * of the stack; when that line finishes, the execution continues on the * older lines on the stack where it stopped before. * * 4 Same * On config reload, the filters have to be compared whether channel * reload is needed or not. The comparison is done by comparing the * struct f_line's recursively. * * The main purpose of this rework was to improve filter performance * by making the interpreter non-recursive. * * The other outcome is concentration of instruction definitions to * one place -- right here. You shall define your instruction only here * and nowhere else. * * Beware. This file is interpreted by M4 macros. These macros * may be more stupid than you could imagine. If something strange * happens after changing this file, compare the results before and * after your change (see the Makefile to find out where the results are) * and see what really happened. * * This file is not directly a C source code -> it is a generator input * for several C sources; every instruction block gets expanded into many * different places. * * All the arguments are processed literally; if you need an argument including comma, * you have to quote it by [[ ... ]] * * What is the syntax here? * m4_dnl INST(FI_NOP, in, out) { enum value, input args, output args * m4_dnl ARG(num, type); argument, its id (in data fields) and type accessible by v1, v2, v3 * m4_dnl ARG_ANY(num); argument with no type check accessible by v1, v2, v3 * m4_dnl ARG_TYPE(num, type); just declare the type of argument * m4_dnl VARARG; variable-length argument list; accessible by vv(i) and whati->varcount * m4_dnl LINE(num, out); this argument has to be converted to its own f_line * m4_dnl SYMBOL; symbol handed from config * m4_dnl STATIC_ATTR; static attribute definition * m4_dnl DYNAMIC_ATTR; dynamic attribute definition * m4_dnl RTC; route table config * m4_dnl ACCESS_RTE; this instruction needs route * * m4_dnl FID_MEMBER( custom instruction member * m4_dnl C type, for storage in structs * m4_dnl name, how the member is named * m4_dnl comparator for same(), if different, this should be TRUE (CAVEAT) * m4_dnl dump format string debug -> format string for bvsnprintf * m4_dnl dump format args appropriate args * m4_dnl ) * * m4_dnl RESULT(type, union-field, value); putting this on value stack * m4_dnl RESULT_(type, union-field, value); like RESULT(), but do not declare the type * m4_dnl RESULT_VAL(value-struct); pass the struct f_val directly * m4_dnl RESULT_TYPE(type); just declare the type of result value * m4_dnl RESULT_VOID; return undef * m4_dnl } * * Note that runtime arguments m4_dnl (ARG*, VARARG) must be defined before * parse-time arguments m4_dnl (LINE, SYMBOL, ...). During linearization, * first ones move position in f_line by linearizing arguments first, while * second ones store data to the current position. * * Also note that the { ... } blocks are not respected by M4 at all. * If you get weird unmatched-brace-pair errors, check what it generated and why. * What is really considered as one instruction is not the { ... } block * after m4_dnl INST() but all the code between them. * * Other code is just copied into the interpreter part. * * The filter language uses a simple type system, where values have types * (constants T_*) and also terms (instructions) are statically typed. Our * static typing is partial (some terms do not declare types of arguments * or results), therefore it can detect most but not all type errors and * therefore we still have runtime type checks. * * m4_dnl Types of arguments are declared by macros ARG() and ARG_TYPE(), * m4_dnl types of results are declared by RESULT() and RESULT_TYPE(). * m4_dnl Macros ARG_ANY(), RESULT_() and RESULT_VAL() do not declare types * m4_dnl themselves, but can be combined with ARG_TYPE() / RESULT_TYPE(). * * m4_dnl Note that types should be declared only once. If there are * m4_dnl multiple RESULT() macros in an instruction definition, they must * m4_dnl use the exact same expression for type, or they should be replaced * m4_dnl by multiple RESULT_() macros and a common RESULT_TYPE() macro. * m4_dnl See e.g. FI_EA_GET or FI_MIN instructions. * * * If you are satisfied with this, you don't need to read the following * detailed description of what is really done with the instruction definitions. * * m4_dnl Now let's look under the cover. The code between each INST() * m4_dnl is copied to several places, namely these (numbered by the M4 diversions * m4_dnl used in filter/decl.m4): * * m4_dnl (102) struct f_inst *f_new_inst(FI_EXAMPLE [[ put it here ]]) * m4_dnl { * m4_dnl ... (common code) * m4_dnl (103) [[ put it here ]] * m4_dnl ... * m4_dnl if (all arguments are constant) * m4_dnl (108) [[ put it here ]] * m4_dnl } * m4_dnl For writing directly to constructor argument list, use FID_NEW_ARGS. * m4_dnl For computing something in constructor (103), use FID_NEW_BODY. * m4_dnl For constant pre-interpretation (108), see below at FID_INTERPRET_BODY. * * m4_dnl struct f_inst { * m4_dnl ... (common fields) * m4_dnl union { * m4_dnl struct { * m4_dnl (101) [[ put it here ]] * m4_dnl } i_FI_EXAMPLE; * m4_dnl ... * m4_dnl }; * m4_dnl }; * m4_dnl This structure is returned from constructor. * m4_dnl For writing directly to this structure, use FID_STRUCT_IN. * * m4_dnl linearize(struct f_line *dest, const struct f_inst *what, uint pos) { * m4_dnl ... * m4_dnl switch (what->fi_code) { * m4_dnl case FI_EXAMPLE: * m4_dnl (105) [[ put it here ]] * m4_dnl break; * m4_dnl } * m4_dnl } * m4_dnl This is called when translating from struct f_inst to struct f_line_item. * m4_dnl For accessing your custom instruction data, use following macros: * m4_dnl whati -> for accessing (struct f_inst).i_FI_EXAMPLE * m4_dnl item -> for accessing (struct f_line)[pos].i_FI_EXAMPLE * m4_dnl For writing directly here, use FID_LINEARIZE_BODY. * * m4_dnl (107) struct f_line_item { * m4_dnl ... (common fields) * m4_dnl union { * m4_dnl struct { * m4_dnl (101) [[ put it here ]] * m4_dnl } i_FI_EXAMPLE; * m4_dnl ... * m4_dnl }; * m4_dnl }; * m4_dnl The same as FID_STRUCT_IN (101) but for the other structure. * m4_dnl This structure is returned from the linearizer (105). * m4_dnl For writing directly to this structure, use FID_LINE_IN. * * m4_dnl f_dump_line_item_FI_EXAMPLE(const struct f_line_item *item, const int indent) * m4_dnl { * m4_dnl (104) [[ put it here ]] * m4_dnl } * m4_dnl This code dumps the instruction on debug. Note that the argument * m4_dnl is the linearized instruction; if the instruction has arguments, * m4_dnl their code has already been linearized and their value is taken * m4_dnl from the value stack. * m4_dnl For writing directly here, use FID_DUMP_BODY. * * m4_dnl f_same(...) * m4_dnl { * m4_dnl switch (f1_->fi_code) { * m4_dnl case FI_EXAMPLE: * m4_dnl (106) [[ put it here ]] * m4_dnl break; * m4_dnl } * m4_dnl } * m4_dnl This code compares the two given instrucions (f1_ and f2_) * m4_dnl on reconfigure. For accessing your custom instruction data, * m4_dnl use macros f1 and f2. * m4_dnl For writing directly here, use FID_SAME_BODY. * * m4_dnl f_add_lines(...) * m4_dnl { * m4_dnl switch (what_->fi_code) { * m4_dnl case FI_EXAMPLE: * m4_dnl (109) [[ put it here ]] * m4_dnl break; * m4_dnl } * m4_dnl } * m4_dnl This code adds new filter lines reachable from the instruction * m4_dnl to the filter iterator line buffer. This is for instructions * m4_dnl that changes conrol flow, like FI_CONDITION or FI_CALL, most * m4_dnl instructions do not need to update it. It is used in generic * m4_dnl filter iteration code (FILTER_ITERATE*). For accessing your * m4_dnl custom instruction data, use macros f1 and f2. For writing * m4_dnl directly here, use FID_ITERATE_BODY. * * m4_dnl interpret(...) * m4_dnl { * m4_dnl switch (what->fi_code) { * m4_dnl case FI_EXAMPLE: * m4_dnl (108) [[ put it here ]] * m4_dnl break; * m4_dnl } * m4_dnl } * m4_dnl This code executes the instruction. Every pre-defined macro * m4_dnl resets the output here. For setting it explicitly, * m4_dnl use FID_INTERPRET_BODY. * m4_dnl This code is put on two places; one is the interpreter, the other * m4_dnl is instruction constructor. If you need to distinguish between * m4_dnl these two, use FID_INTERPRET_EXEC or FID_INTERPRET_NEW respectively. * m4_dnl To address the difference between interpreter and constructor * m4_dnl environments, there are several convenience macros defined: * m4_dnl runtime() -> for spitting out runtime error like division by zero * m4_dnl RESULT(...) -> declare result; may overwrite arguments * m4_dnl v1, v2, v3 -> positional arguments, may be overwritten by RESULT() * m4_dnl falloc(size) -> allocate memory from the appropriate linpool * m4_dnl fpool -> the current linpool * m4_dnl NEVER_CONSTANT-> don't generate pre-interpretation code at all * m4_dnl ACCESS_RTE -> check that route is available, also NEVER_CONSTANT * * m4_dnl If you are stymied, see FI_CALL or FI_CONSTANT or just search for * m4_dnl the mentioned macros in this file to see what is happening there in wild. * * * A note about soundness of the type system: * * A type system is sound when types of expressions are consistent with * types of values resulting from evaluation of such expressions. Untyped * expressions are ok, but badly typed expressions are not sound. So is * the type system of BIRD filtering code sound? There are some points: * * All cases of (one) m4_dnl RESULT() macro are obviously ok, as the macro * both declares a type and returns a value. One have to check instructions * that use m4_dnl RESULT_TYPE() macro. There are two issues: * * FI_AND, FI_OR - second argument is statically checked to be T_BOOL and * passed as result without dynamic typecheck, declared to be T_BOOL. If * an untyped non-bool expression is used as a second argument, then * the mismatched type is returned. * * FI_VAR_GET - soundness depends on consistency of declared symbol types * and stored values. This is maintained when values are stored by * FI_VAR_SET, but when they are stored by FI_CALL, only static checking is * used, so when an untyped expression returning mismatched value is used * as a function argument, then inconsistent value is stored and subsequent * FI_VAR_GET would be unsound. * * Both of these issues are inconsequential, as mismatched values from * unsound expressions will be caught by dynamic typechecks like mismatched * values from untyped expressions. * * Also note that FI_CALL is the only expression without properly declared * result type. */ /* Binary operators */ INST(FI_ADD, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); RESULT(T_INT, i, v1.val.i + v2.val.i); } INST(FI_SUBTRACT, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); RESULT(T_INT, i, v1.val.i - v2.val.i); } INST(FI_MULTIPLY, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); RESULT(T_INT, i, v1.val.i * v2.val.i); } INST(FI_DIVIDE, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); if (v2.val.i == 0) runtime( "Mother told me not to divide by 0" ); RESULT(T_INT, i, v1.val.i / v2.val.i); } INST(FI_BITOR, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); RESULT(T_INT, i, v1.val.i | v2.val.i); } INST(FI_BITAND, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); RESULT(T_INT, i, v1.val.i & v2.val.i); } INST(FI_AND, 1, 1) { ARG(1,T_BOOL); ARG_TYPE_STATIC(2,T_BOOL); RESULT_TYPE(T_BOOL); if (v1.val.i) LINE(2,1); else RESULT_VAL(v1); } INST(FI_OR, 1, 1) { ARG(1,T_BOOL); ARG_TYPE_STATIC(2,T_BOOL); RESULT_TYPE(T_BOOL); if (!v1.val.i) LINE(2,1); else RESULT_VAL(v1); } INST(FI_PAIR_CONSTRUCT, 2, 1) { ARG(1,T_INT); ARG(2,T_INT); uint u1 = v1.val.i; uint u2 = v2.val.i; if ((u1 > 0xFFFF) || (u2 > 0xFFFF)) runtime( "Can't operate with value out of bounds in pair constructor" ); RESULT(T_PAIR, i, (u1 << 16) | u2); } INST(FI_EC_CONSTRUCT, 2, 1) { ARG_ANY(1); ARG(2, T_INT); FID_MEMBER(enum ec_subtype, ecs, f1->ecs != f2->ecs, "ec subtype %s", ec_subtype_str(item->ecs)); int ipv4_used; u32 key, val; if (v1.type == T_INT) { ipv4_used = 0; key = v1.val.i; } else if (v1.type == T_QUAD) { ipv4_used = 1; key = v1.val.i; } /* IP->Quad implicit conversion */ else if (val_is_ip4(&v1)) { ipv4_used = 1; key = ipa_to_u32(v1.val.ip); } else runtime("Argument 1 of EC constructor must be integer or IPv4 address, got 0x%02x", v1.type); val = v2.val.i; if (ecs == EC_GENERIC) RESULT(T_EC, ec, ec_generic(key, val)); else if (ipv4_used) if (val <= 0xFFFF) RESULT(T_EC, ec, ec_ip4(ecs, key, val)); else runtime("4-byte value %u can't be used with IP-address key in extended community", val); else if (key < 0x10000) RESULT(T_EC, ec, ec_as2(ecs, key, val)); else if (val <= 0xFFFF) RESULT(T_EC, ec, ec_as4(ecs, key, val)); else runtime("4-byte value %u can't be used with 4-byte ASN in extended community", val); } INST(FI_LC_CONSTRUCT, 3, 1) { ARG(1, T_INT); ARG(2, T_INT); ARG(3, T_INT); RESULT(T_LC, lc, [[(lcomm) { v1.val.i, v2.val.i, v3.val.i }]]); } INST(FI_PATHMASK_CONSTRUCT, 0, 1) { VARARG; struct f_path_mask *pm = falloc(sizeof(struct f_path_mask) + whati->varcount * sizeof(struct f_path_mask_item)); pm->len = whati->varcount; for (uint i=0; ivarcount; i++) { switch (vv(i).type) { case T_PATH_MASK_ITEM: if (vv(i).val.pmi.kind == PM_LOOP) { if (i == 0) runtime("Path mask iterator '+' cannot be first"); /* We want PM_LOOP as prefix operator */ pm->item[i] = pm->item[i - 1]; pm->item[i - 1] = vv(i).val.pmi; break; } pm->item[i] = vv(i).val.pmi; break; case T_INT: pm->item[i] = (struct f_path_mask_item) { .asn = vv(i).val.i, .kind = PM_ASN, }; break; case T_SET: if (!path_set_type(vv(i).val.t)) runtime("Only integer sets allowed in path mask"); pm->item[i] = (struct f_path_mask_item) { .set = vv(i).val.t, .kind = PM_ASN_SET, }; break; default: runtime( "Error resolving path mask template: value not an integer" ); } } RESULT(T_PATH_MASK, path_mask, pm); } /* Relational operators */ INST(FI_NEQ, 2, 1) { ARG_ANY(1); ARG_ANY(2); ARG_PREFER_SAME_TYPE(1, 2); RESULT(T_BOOL, i, !val_same(&v1, &v2)); } INST(FI_EQ, 2, 1) { ARG_ANY(1); ARG_ANY(2); ARG_PREFER_SAME_TYPE(1, 2); RESULT(T_BOOL, i, val_same(&v1, &v2)); } INST(FI_LT, 2, 1) { ARG_ANY(1); ARG_ANY(2); ARG_SAME_TYPE(1, 2); int i = val_compare(&v1, &v2); if (i == F_CMP_ERROR) runtime( "Can't compare values of incompatible types" ); RESULT(T_BOOL, i, (i == -1)); } INST(FI_LTE, 2, 1) { ARG_ANY(1); ARG_ANY(2); ARG_SAME_TYPE(1, 2); int i = val_compare(&v1, &v2); if (i == F_CMP_ERROR) runtime( "Can't compare values of incompatible types" ); RESULT(T_BOOL, i, (i != 1)); } INST(FI_NOT, 1, 1) { ARG(1,T_BOOL); RESULT(T_BOOL, i, !v1.val.i); } INST(FI_MATCH, 2, 1) { ARG_ANY(1); ARG_ANY(2); int i = val_in_range(&v1, &v2); if (i == F_CMP_ERROR) runtime( "~ applied on unknown type pair" ); RESULT(T_BOOL, i, !!i); } INST(FI_NOT_MATCH, 2, 1) { ARG_ANY(1); ARG_ANY(2); int i = val_in_range(&v1, &v2); if (i == F_CMP_ERROR) runtime( "!~ applied on unknown type pair" ); RESULT(T_BOOL, i, !i); } INST(FI_DEFINED, 1, 1) { ARG_ANY(1); RESULT(T_BOOL, i, (v1.type != T_VOID) && !undef_value(v1)); } INST(FI_TYPE, 1, 1) { ARG_ANY(1); /* There may be more types supporting this operation */ switch (v1.type) { case T_NET: RESULT(T_ENUM_NETTYPE, i, v1.val.net->type); break; default: runtime( "Can't determine type of this item" ); } } INST(FI_IS_V4, 1, 1) { ARG(1, T_IP); RESULT(T_BOOL, i, ipa_is_ip4(v1.val.ip)); } INST(FI_VAR_INIT, 1, 0) { NEVER_CONSTANT; ARG_ANY(1); SYMBOL; ARG_TYPE(1, sym->class & 0xff); /* New variable is always the last on stack */ uint pos = curline.vbase + sym->offset; fstk->vstk[pos] = v1; fstk->vcnt = pos + 1; } /* Set to indirect value prepared in v1 */ INST(FI_VAR_SET, 1, 0) { NEVER_CONSTANT; ARG_ANY(1); SYMBOL; ARG_TYPE(1, sym->class & 0xff); fstk->vstk[curline.vbase + sym->offset] = v1; } INST(FI_VAR_GET, 0, 1) { SYMBOL; NEVER_CONSTANT; RESULT_TYPE(sym->class & 0xff); RESULT_VAL(fstk->vstk[curline.vbase + sym->offset]); } INST(FI_CONSTANT, 0, 1) { FID_MEMBER( struct f_val, val, [[ !val_same(&(f1->val), &(f2->val)) ]], "value %s", val_dump(&(item->val)) ); RESULT_TYPE(val.type); RESULT_VAL(val); } INST(FI_FOR_INIT, 1, 0) { NEVER_CONSTANT; ARG_ANY(1); SYMBOL; FID_NEW_BODY() ASSERT((sym->class & ~0xff) == SYM_VARIABLE); /* Static type check */ if (f1->type) { enum btype t_var = (sym->class & 0xff); enum btype t_arg = f_type_element_type(f1->type); if (!t_arg) cf_error("Value of expression in FOR must be iterable, got %s", f_type_name(f1->type)); if (t_var != t_arg) cf_error("Loop variable '%s' in FOR must be %s, is %s", sym->name, f_type_name(t_arg), f_type_name(t_var)); } FID_INTERPRET_BODY() /* Dynamic type check */ if ((sym->class & 0xff) != f_type_element_type(v1.type)) runtime("Mismatched argument and variable type"); /* Setup the index */ v2 = (struct f_val) { .type = T_INT, .val.i = 0 }; /* Keep v1 and v2 on the stack */ fstk->vcnt += 2; } INST(FI_FOR_NEXT, 2, 0) { NEVER_CONSTANT; SYMBOL; /* Type checks are done in FI_FOR_INIT */ /* Loop variable */ struct f_val *var = &fstk->vstk[curline.vbase + sym->offset]; int step = 0; switch(v1.type) { case T_PATH: var->type = T_INT; step = as_path_walk(v1.val.ad, &v2.val.i, &var->val.i); break; case T_CLIST: var->type = T_PAIR; step = int_set_walk(v1.val.ad, &v2.val.i, &var->val.i); break; case T_ECLIST: var->type = T_EC; step = ec_set_walk(v1.val.ad, &v2.val.i, &var->val.ec); break; case T_LCLIST: var->type = T_LC; step = lc_set_walk(v1.val.ad, &v2.val.i, &var->val.lc); break; default: runtime( "Clist or lclist expected" ); } if (step) { /* Keep v1 and v2 on the stack */ fstk->vcnt += 2; /* Repeat this instruction */ curline.pos--; /* Execute the loop body */ LINE(1, 0); /* Space for loop variable, may be unused */ fstk->vcnt += 1; } else var->type = T_VOID; } INST(FI_CONDITION, 1, 0) { ARG(1, T_BOOL); if (v1.val.i) LINE(2,0); else LINE(3,0); } INST(FI_PRINT, 0, 0) { NEVER_CONSTANT; VARARG; if (whati->varcount && !(fs->flags & FF_SILENT)) for (uint i=0; ivarcount; i++) val_format(&(vv(i)), &fs->buf); } INST(FI_FLUSH, 0, 0) { NEVER_CONSTANT; if (!(fs->flags & FF_SILENT)) /* After log_commit, the buffer is reset */ log_commit(*L_INFO, &fs->buf); } INST(FI_DIE, 0, 0) { NEVER_CONSTANT; FID_MEMBER(enum filter_return, fret, f1->fret != f2->fret, "%s", filter_return_str(item->fret)); switch (whati->fret) { case F_ACCEPT: /* Should take care about turning ACCEPT into MODIFY */ case F_ERROR: case F_REJECT: /* Maybe print complete route along with reason to reject route? */ return fret; /* We have to return now, no more processing. */ default: bug( "unknown return type: Can't happen"); } } INST(FI_RTA_GET, 0, 1) { { STATIC_ATTR; ACCESS_RTE; switch (sa.sa_code) { case SA_NET: RESULT(sa.type, net, fs->rte->net); break; case SA_PROTO: RESULT(sa.type, s, fs->rte->src->owner->name); break; default: { struct eattr *nhea = ea_find(fs->rte->attrs, &ea_gen_nexthop); struct nexthop_adata *nhad = nhea ? (struct nexthop_adata *) nhea->u.ptr : NULL; struct nexthop *nh = nhad ? &nhad->nh : NULL; switch (sa.sa_code) { case SA_DEST: RESULT(sa.type, i, nhad ? (NEXTHOP_IS_REACHABLE(nhad) ? RTD_UNICAST : nhad->dest) : RTD_NONE); break; case SA_GW: RESULT(sa.type, ip, nh ? nh->gw : IPA_NONE); break; case SA_IFNAME: RESULT(sa.type, s, (nh && nh->iface) ? nh->iface->name : ""); break; case SA_IFINDEX: RESULT(sa.type, i, (nh && nh->iface) ? nh->iface->index : 0); break; case SA_WEIGHT: RESULT(sa.type, i, (nh ? nh->weight : 0) + 1); break; case SA_GW_MPLS: RESULT(sa.type, i, (nh && nh->labels) ? nh->label[0] : MPLS_NULL); break; default: bug("Invalid static attribute access (%u/%u)", sa.type, sa.sa_code); } } } } } INST(FI_RTA_SET, 1, 0) { ACCESS_RTE; ARG_ANY(1); STATIC_ATTR; ARG_TYPE(1, sa.type); { union { struct nexthop_adata nha; struct { struct adata ad; struct nexthop nh; u32 label; }; } nha; nha.ad = (struct adata) { .length = sizeof (struct nexthop_adata) - sizeof (struct adata), }; eattr *a = NULL; switch (sa.sa_code) { case SA_DEST: { int i = v1.val.i; if ((i != RTD_BLACKHOLE) && (i != RTD_UNREACHABLE) && (i != RTD_PROHIBIT)) runtime( "Destination can be changed only to blackhole, unreachable or prohibit" ); nha.nha.dest = i; nha.ad.length = NEXTHOP_DEST_SIZE; break; } case SA_GW: { struct eattr *nh_ea = ea_find(fs->rte->attrs, &ea_gen_nexthop); ip_addr ip = v1.val.ip; struct iface *ifa = (ipa_is_link_local(ip) && nh_ea) ? ((struct nexthop_adata *) nh_ea->u.ptr)->nh.iface : NULL; /* XXX this code supposes that every owner is a protocol XXX */ neighbor *n = neigh_find(SKIP_BACK(struct proto, sources, fs->rte->src->owner), ip, ifa, 0); if (!n || (n->scope == SCOPE_HOST)) runtime( "Invalid gw address" ); nha.nh = (struct nexthop) { .gw = ip, .iface = n->iface, }; } break; case SA_IFNAME: { struct iface *ifa = if_find_by_name(v1.val.s); if (!ifa) runtime( "Invalid iface name" ); nha.nh = (struct nexthop) { .iface = ifa, }; } break; case SA_GW_MPLS: { if (v1.val.i >= 0x100000) runtime( "Invalid MPLS label" ); struct eattr *nh_ea = ea_find(fs->rte->attrs, &ea_gen_nexthop); if (!nh_ea) runtime( "No nexthop to add a MPLS label to" ); nha.nh = ((struct nexthop_adata *) nh_ea->u.ptr)->nh; if (v1.val.i != MPLS_NULL) { nha.nh.label[0] = v1.val.i; nha.nh.labels = 1; nha.ad.length = sizeof nha - sizeof (struct adata); } else nha.nh.labels = 0; } break; case SA_WEIGHT: { int i = v1.val.i; if (i < 1 || i > 256) runtime( "Setting weight value out of bounds" ); struct eattr *nh_ea = ea_find(fs->rte->attrs, &ea_gen_nexthop); if (!nh_ea) runtime( "No nexthop to set weight on" ); struct nexthop_adata *nhad = (struct nexthop_adata *) nh_ea->u.ptr; if (!NEXTHOP_IS_REACHABLE(nhad)) runtime( "Setting weight needs regular nexthop " ); struct nexthop_adata *nhax = (struct nexthop_adata *) tmp_copy_adata(&nhad->ad); /* Set weight on all next hops */ NEXTHOP_WALK(nh, nhax) nh->weight = i - 1; a = ea_set_attr(&fs->rte->attrs, EA_LITERAL_DIRECT_ADATA(&ea_gen_nexthop, 0, &nhax->ad)); } break; default: bug("Invalid static attribute access (%u/%u)", sa.type, sa.sa_code); } if (!a) a = ea_set_attr(&fs->rte->attrs, EA_LITERAL_DIRECT_ADATA(&ea_gen_nexthop, 0, tmp_copy_adata(&nha.ad))); a->originated = 1; a->fresh = 1; } } INST(FI_EA_GET, 0, 1) { /* Access to extended attributes */ DYNAMIC_ATTR; ACCESS_RTE; RESULT_TYPE(da->type); { const struct f_val *empty; const eattr *e = ea_find(fs->rte->attrs, da->id); if (e) { ASSERT_DIE(e->type == da->type); switch (e->type) { case T_IP: RESULT_(T_IP, ip, *((const ip_addr *) e->u.ptr->data)); break; default: RESULT_VAL([[(struct f_val) { .type = e->type, .val.bval = e->u, }]]); } } else if (empty = f_get_empty(da->type)) RESULT_VAL(*empty); else RESULT_VOID; } } INST(FI_EA_SET, 1, 0) { ACCESS_RTE; ARG_ANY(1); DYNAMIC_ATTR; ARG_TYPE(1, da->type); { struct eattr *a; if (da->type >= EAF_TYPE__MAX) bug("Unsupported attribute type"); switch (da->type) { case T_OPAQUE: case T_IFACE: runtime( "Setting opaque attribute is not allowed" ); break; case T_IP: a = ea_set_attr(&fs->rte->attrs, EA_LITERAL_STORE_ADATA(da, 0, &v1.val.ip, sizeof(ip_addr))); break; default: a = ea_set_attr(&fs->rte->attrs, EA_LITERAL_GENERIC(da->id, da->type, 0, .u = v1.val.bval)); break; } a->originated = 1; a->fresh = 1; } } INST(FI_EA_UNSET, 0, 0) { DYNAMIC_ATTR; ACCESS_RTE; ea_unset_attr(&fs->rte->attrs, 1, da); } INST(FI_DEFAULT, 2, 1) { ARG_ANY(1); ARG_ANY(2); RESULT_TYPE(f_type_element_type(v2.type)); log(L_INFO "Type of arg 1 is: %d", v1.type); if (v1.type == T_VOID) RESULT_VAL(v2); else RESULT_VAL(v1); } INST(FI_LENGTH, 1, 1) { /* Get length of */ ARG_ANY(1); switch(v1.type) { case T_NET: RESULT(T_INT, i, net_pxlen(v1.val.net)); break; case T_PATH: RESULT(T_INT, i, as_path_getlen(v1.val.ad)); break; case T_CLIST: RESULT(T_INT, i, int_set_get_size(v1.val.ad)); break; case T_ECLIST: RESULT(T_INT, i, ec_set_get_size(v1.val.ad)); break; case T_LCLIST: RESULT(T_INT, i, lc_set_get_size(v1.val.ad)); break; default: runtime( "Prefix, path, clist or eclist expected" ); } } INST(FI_NET_SRC, 1, 1) { /* Get src prefix */ ARG(1, T_NET); net_addr_union *net = (void *) v1.val.net; net_addr *src = falloc(sizeof(net_addr_ip6)); const byte *part; switch(v1.val.net->type) { case NET_FLOW4: part = flow4_get_part(&net->flow4, FLOW_TYPE_SRC_PREFIX); if (part) net_fill_ip4(src, flow_read_ip4_part(part), flow_read_pxlen(part)); else net_fill_ip4(src, IP4_NONE, 0); break; case NET_FLOW6: part = flow6_get_part(&net->flow6, FLOW_TYPE_SRC_PREFIX); if (part) net_fill_ip6(src, flow_read_ip6_part(part), flow_read_pxlen(part)); else net_fill_ip6(src, IP6_NONE, 0); break; case NET_IP6_SADR: net_fill_ip6(src, net->ip6_sadr.src_prefix, net->ip6_sadr.src_pxlen); break; default: runtime( "Flow or SADR expected" ); } RESULT(T_NET, net, src); } INST(FI_NET_DST, 1, 1) { /* Get dst prefix */ ARG(1, T_NET); net_addr_union *net = (void *) v1.val.net; net_addr *dst = falloc(sizeof(net_addr_ip6)); const byte *part; switch(v1.val.net->type) { case NET_FLOW4: part = flow4_get_part(&net->flow4, FLOW_TYPE_DST_PREFIX); if (part) net_fill_ip4(dst, flow_read_ip4_part(part), flow_read_pxlen(part)); else net_fill_ip4(dst, IP4_NONE, 0); break; case NET_FLOW6: part = flow6_get_part(&net->flow6, FLOW_TYPE_DST_PREFIX); if (part) net_fill_ip6(dst, flow_read_ip6_part(part), flow_read_pxlen(part)); else net_fill_ip6(dst, IP6_NONE, 0); break; case NET_IP6_SADR: net_fill_ip6(dst, net->ip6_sadr.dst_prefix, net->ip6_sadr.dst_pxlen); break; default: runtime( "Flow or SADR expected" ); } RESULT(T_NET, net, dst); } INST(FI_ROA_MAXLEN, 1, 1) { /* Get ROA max prefix length */ ARG(1, T_NET); if (!net_is_roa(v1.val.net)) runtime( "ROA expected" ); RESULT(T_INT, i, (v1.val.net->type == NET_ROA4) ? ((net_addr_roa4 *) v1.val.net)->max_pxlen : ((net_addr_roa6 *) v1.val.net)->max_pxlen); } INST(FI_ASN, 1, 1) { /* Get ROA ASN or community ASN part */ ARG_ANY(1); RESULT_TYPE(T_INT); switch(v1.type) { case T_NET: if (!net_is_roa(v1.val.net)) runtime( "ROA expected" ); RESULT_(T_INT, i, (v1.val.net->type == NET_ROA4) ? ((net_addr_roa4 *) v1.val.net)->asn : ((net_addr_roa6 *) v1.val.net)->asn); break; case T_PAIR: RESULT_(T_INT, i, v1.val.i >> 16); break; case T_LC: RESULT_(T_INT, i, v1.val.lc.asn); break; default: runtime( "Net, pair or lc expected" ); } } INST(FI_IP, 1, 1) { /* Convert prefix to ... */ ARG(1, T_NET); RESULT(T_IP, ip, net_prefix(v1.val.net)); } INST(FI_ROUTE_DISTINGUISHER, 1, 1) { ARG(1, T_NET); if (!net_is_vpn(v1.val.net)) runtime( "VPN address expected" ); RESULT(T_RD, ec, net_rd(v1.val.net)); } INST(FI_AS_PATH_FIRST, 1, 1) { /* Get first ASN from AS PATH */ ARG(1, T_PATH); u32 as = 0; as_path_get_first(v1.val.ad, &as); RESULT(T_INT, i, as); } INST(FI_AS_PATH_LAST, 1, 1) { /* Get last ASN from AS PATH */ ARG(1, T_PATH); u32 as = 0; as_path_get_last(v1.val.ad, &as); RESULT(T_INT, i, as); } INST(FI_AS_PATH_LAST_NAG, 1, 1) { /* Get last ASN from non-aggregated part of AS PATH */ ARG(1, T_PATH); RESULT(T_INT, i, as_path_get_last_nonaggregated(v1.val.ad)); } INST(FI_PAIR_DATA, 1, 1) { /* Get data part from the standard community */ ARG(1, T_PAIR); RESULT(T_INT, i, v1.val.i & 0xFFFF); } INST(FI_LC_DATA1, 1, 1) { /* Get data1 part from the large community */ ARG(1, T_LC); RESULT(T_INT, i, v1.val.lc.ldp1); } INST(FI_LC_DATA2, 1, 1) { /* Get data2 part from the large community */ ARG(1, T_LC); RESULT(T_INT, i, v1.val.lc.ldp2); } INST(FI_MIN, 1, 1) { /* Get minimum element from list */ ARG_ANY(1); RESULT_TYPE(f_type_element_type(v1.type)); switch(v1.type) { case T_CLIST: { u32 val = 0; int_set_min(v1.val.ad, &val); RESULT_(T_PAIR, i, val); } break; case T_ECLIST: { u64 val = 0; ec_set_min(v1.val.ad, &val); RESULT_(T_EC, ec, val); } break; case T_LCLIST: { lcomm val = { 0, 0, 0 }; lc_set_min(v1.val.ad, &val); RESULT_(T_LC, lc, val); } break; default: runtime( "Clist or lclist expected" ); } } INST(FI_MAX, 1, 1) { /* Get maximum element from list */ ARG_ANY(1); RESULT_TYPE(f_type_element_type(v1.type)); switch(v1.type) { case T_CLIST: { u32 val = 0; int_set_max(v1.val.ad, &val); RESULT_(T_PAIR, i, val); } break; case T_ECLIST: { u64 val = 0; ec_set_max(v1.val.ad, &val); RESULT_(T_EC, ec, val); } break; case T_LCLIST: { lcomm val = { 0, 0, 0 }; lc_set_max(v1.val.ad, &val); RESULT_(T_LC, lc, val); } break; default: runtime( "Clist or lclist expected" ); } } INST(FI_RETURN, 1, 0) { NEVER_CONSTANT; /* Acquire the return value */ ARG_ANY(1); uint retpos = fstk->vcnt; /* Drop every sub-block including ourselves */ do fstk->ecnt--; while ((fstk->ecnt > 0) && !(fstk->estk[fstk->ecnt].emask & FE_RETURN)); /* Now we are at the caller frame; if no such, try to convert to accept/reject. */ if (!fstk->ecnt) { if (fstk->vstk[retpos].type == T_BOOL) return (fstk->vstk[retpos].val.i) ? F_ACCEPT : F_REJECT; else runtime("Can't return non-bool from non-function"); } /* Set the value stack position, overwriting the former implicit void */ fstk->vcnt = fstk->estk[fstk->ecnt].ventry - 1; /* Copy the return value */ RESULT_VAL(fstk->vstk[retpos]); } INST(FI_CALL, 0, 1) { NEVER_CONSTANT; VARARG; SYMBOL; /* Fake result type declaration */ RESULT_TYPE(T_VOID); FID_NEW_BODY() ASSERT(sym->class == SYM_FUNCTION); if (whati->varcount != sym->function->args) cf_error("Function '%s' expects %u arguments, got %u arguments", sym->name, sym->function->args, whati->varcount); /* Typecheck individual arguments */ struct f_inst *a = fvar; struct f_arg *b = sym->function->arg_list; for (uint i = 1; a && b; a = a->next, b = b->next, i++) { enum btype b_type = b->arg->class & 0xff; if (a->type && (a->type != b_type) && !f_const_promotion(a, b_type)) cf_error("Argument %u of '%s' must be %s, got %s", i, sym->name, f_type_name(b_type), f_type_name(a->type)); } ASSERT(!a && !b); /* Add implicit void slot for the return value */ struct f_inst *tmp = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_VOID }); tmp->next = whati->fvar; whati->fvar = tmp; what->size += tmp->size; /* Mark recursive calls, they have dummy f_line */ if (!sym->function->len) what->flags |= FIF_RECURSIVE; FID_SAME_BODY() if (!(f1->sym->flags & SYM_FLAG_SAME) && !(f1_->flags & FIF_RECURSIVE)) return 0; FID_ITERATE_BODY() if (!(what->flags & FIF_RECURSIVE)) BUFFER_PUSH(fit->lines) = whati->sym->function; FID_INTERPRET_BODY() /* Push the body on stack */ LINEX(sym->function); curline.vbase = curline.ventry; curline.emask |= FE_RETURN; /* Arguments on stack */ fstk->vcnt += sym->function->args; /* Storage for local variables */ f_vcnt_check_overflow(sym->function->vars); memset(&(fstk->vstk[fstk->vcnt]), 0, sizeof(struct f_val) * sym->function->vars); fstk->vcnt += sym->function->vars; } INST(FI_DROP_RESULT, 1, 0) { NEVER_CONSTANT; ARG_ANY(1); } INST(FI_SWITCH, 1, 0) { ARG_ANY(1); FID_MEMBER(struct f_tree *, tree, [[!same_tree(f1->tree, f2->tree)]], "tree %p", item->tree); FID_ITERATE_BODY() tree_walk(whati->tree, f_add_tree_lines, fit); FID_INTERPRET_BODY() const struct f_tree *t = find_tree(tree, &v1); if (!t) { v1.type = T_VOID; t = find_tree(tree, &v1); if (!t) { debug( "No else statement?\n"); FID_HIC(,break,return NULL); } } /* It is actually possible to have t->data NULL */ LINEX(t->data); } INST(FI_IP_MASK, 2, 1) { /* IP.MASK(val) */ ARG(1, T_IP); ARG(2, T_INT); RESULT(T_IP, ip, [[ ipa_is_ip4(v1.val.ip) ? ipa_from_ip4(ip4_and(ipa_to_ip4(v1.val.ip), ip4_mkmask(v2.val.i))) : ipa_from_ip6(ip6_and(ipa_to_ip6(v1.val.ip), ip6_mkmask(v2.val.i))) ]]); } INST(FI_PATH_PREPEND, 2, 1) { /* Path prepend */ ARG(1, T_PATH); ARG(2, T_INT); RESULT(T_PATH, ad, [[ as_path_prepend(fpool, v1.val.ad, v2.val.i) ]]); } INST(FI_CLIST_ADD, 2, 1) { /* (Extended) Community list add */ ARG_ANY(1); ARG_ANY(2); RESULT_TYPE(f1->type); if (v1.type == T_PATH) runtime("Can't add to path"); else if (v1.type == T_CLIST) { /* Community (or cluster) list */ struct f_val dummy; if ((v2.type == T_PAIR) || (v2.type == T_QUAD)) RESULT_(T_CLIST, ad, [[ int_set_add(fpool, v1.val.ad, v2.val.i) ]]); /* IP->Quad implicit conversion */ else if (val_is_ip4(&v2)) RESULT_(T_CLIST, ad, [[ int_set_add(fpool, v1.val.ad, ipa_to_u32(v2.val.ip)) ]]); else if ((v2.type == T_SET) && clist_set_type(v2.val.t, &dummy)) runtime("Can't add set"); else if (v2.type == T_CLIST) RESULT_(T_CLIST, ad, [[ int_set_union(fpool, v1.val.ad, v2.val.ad) ]]); else runtime("Can't add non-pair"); } else if (v1.type == T_ECLIST) { /* v2.val is either EC or EC-set */ if ((v2.type == T_SET) && eclist_set_type(v2.val.t)) runtime("Can't add set"); else if (v2.type == T_ECLIST) RESULT_(T_ECLIST, ad, [[ ec_set_union(fpool, v1.val.ad, v2.val.ad) ]]); else if (v2.type != T_EC) runtime("Can't add non-ec"); else RESULT_(T_ECLIST, ad, [[ ec_set_add(fpool, v1.val.ad, v2.val.ec) ]]); } else if (v1.type == T_LCLIST) { /* v2.val is either LC or LC-set */ if ((v2.type == T_SET) && lclist_set_type(v2.val.t)) runtime("Can't add set"); else if (v2.type == T_LCLIST) RESULT_(T_LCLIST, ad, [[ lc_set_union(fpool, v1.val.ad, v2.val.ad) ]]); else if (v2.type != T_LC) runtime("Can't add non-lc"); else RESULT_(T_LCLIST, ad, [[ lc_set_add(fpool, v1.val.ad, v2.val.lc) ]]); } else runtime("Can't add to non-[e|l]clist"); } INST(FI_CLIST_DEL, 2, 1) { /* (Extended) Community list add or delete */ ARG_ANY(1); ARG_ANY(2); RESULT_TYPE(f1->type); if (v1.type == T_PATH) { if ((v2.type == T_SET) && path_set_type(v2.val.t) || (v2.type == T_INT)) RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, &v2, 0) ]]); else runtime("Can't delete non-integer (set)"); } else if (v1.type == T_CLIST) { /* Community (or cluster) list */ struct f_val dummy; if ((v2.type == T_PAIR) || (v2.type == T_QUAD)) RESULT_(T_CLIST, ad, [[ int_set_del(fpool, v1.val.ad, v2.val.i) ]]); /* IP->Quad implicit conversion */ else if (val_is_ip4(&v2)) RESULT_(T_CLIST, ad, [[ int_set_del(fpool, v1.val.ad, ipa_to_u32(v2.val.ip)) ]]); else if ((v2.type == T_SET) && clist_set_type(v2.val.t, &dummy) || (v2.type == T_CLIST)) RESULT_(T_CLIST, ad, [[ clist_filter(fpool, v1.val.ad, &v2, 0) ]]); else runtime("Can't delete non-pair"); } else if (v1.type == T_ECLIST) { /* v2.val is either EC or EC-set */ if ((v2.type == T_SET) && eclist_set_type(v2.val.t) || (v2.type == T_ECLIST)) RESULT_(T_ECLIST, ad, [[ eclist_filter(fpool, v1.val.ad, &v2, 0) ]]); else if (v2.type != T_EC) runtime("Can't delete non-ec"); else RESULT_(T_ECLIST, ad, [[ ec_set_del(fpool, v1.val.ad, v2.val.ec) ]]); } else if (v1.type == T_LCLIST) { /* v2.val is either LC or LC-set */ if ((v2.type == T_SET) && lclist_set_type(v2.val.t) || (v2.type == T_LCLIST)) RESULT_(T_LCLIST, ad, [[ lclist_filter(fpool, v1.val.ad, &v2, 0) ]]); else if (v2.type != T_LC) runtime("Can't delete non-lc"); else RESULT_(T_LCLIST, ad, [[ lc_set_del(fpool, v1.val.ad, v2.val.lc) ]]); } else runtime("Can't delete in non-[e|l]clist"); } INST(FI_CLIST_FILTER, 2, 1) { /* (Extended) Community list add or delete */ ARG_ANY(1); ARG_ANY(2); RESULT_TYPE(f1->type); if (v1.type == T_PATH) { if ((v2.type == T_SET) && path_set_type(v2.val.t)) RESULT_(T_PATH, ad, [[ as_path_filter(fpool, v1.val.ad, &v2, 1) ]]); else runtime("Can't filter integer"); } else if (v1.type == T_CLIST) { /* Community (or cluster) list */ struct f_val dummy; if ((v2.type == T_SET) && clist_set_type(v2.val.t, &dummy) || (v2.type == T_CLIST)) RESULT_(T_CLIST, ad, [[ clist_filter(fpool, v1.val.ad, &v2, 1) ]]); else runtime("Can't filter pair"); } else if (v1.type == T_ECLIST) { /* v2.val is either EC or EC-set */ if ((v2.type == T_SET) && eclist_set_type(v2.val.t) || (v2.type == T_ECLIST)) RESULT_(T_ECLIST, ad, [[ eclist_filter(fpool, v1.val.ad, &v2, 1) ]]); else runtime("Can't filter ec"); } else if (v1.type == T_LCLIST) { /* v2.val is either LC or LC-set */ if ((v2.type == T_SET) && lclist_set_type(v2.val.t) || (v2.type == T_LCLIST)) RESULT_(T_LCLIST, ad, [[ lclist_filter(fpool, v1.val.ad, &v2, 1) ]]); else runtime("Can't filter lc"); } else runtime("Can't filter non-[e|l]clist"); } INST(FI_ROA_CHECK, 2, 1) { /* ROA Check */ NEVER_CONSTANT; ARG(1, T_NET); ARG(2, T_INT); RTC(3); rtable *table = rtc->table; u32 as = v2.val.i; if (!table) runtime("Missing ROA table"); if (table->addr_type != NET_ROA4 && table->addr_type != NET_ROA6) runtime("Table type must be either ROA4 or ROA6"); if (table->addr_type != (v1.val.net->type == NET_IP4 ? NET_ROA4 : NET_ROA6)) RESULT(T_ENUM_ROA, i, ROA_UNKNOWN); /* Prefix and table type mismatch */ else RESULT(T_ENUM_ROA, i, [[ net_roa_check(table, v1.val.net, as) ]]); } INST(FI_FORMAT, 1, 1) { /* Format */ ARG_ANY(1); RESULT(T_STRING, s, val_format_str(fpool, &v1)); } INST(FI_ASSERT, 1, 0) { /* Birdtest Assert */ NEVER_CONSTANT; ARG(1, T_BOOL); FID_MEMBER(char *, s, [[strcmp(f1->s, f2->s)]], "string %s", item->s); ASSERT(s); if (!bt_assert_hook) runtime("No bt_assert hook registered, can't assert"); bt_assert_hook(v1.val.i, what); }