static void
emit_ct(struct action_context *ctx, bool recirc_next, bool commit)
{
struct ofpact_conntrack *ct = ofpact_put_CT(ctx->ofpacts);
ct->flags |= commit ? NX_CT_F_COMMIT : 0;
/* If "recirc" is set, we automatically go to the next table. */
if (recirc_next) {
if (ctx->cur_ltable < ctx->n_tables) {
ct->recirc_table = ctx->first_ptable + ctx->cur_ltable + 1;
} else {
action_error(ctx, "\"ct_next\" action not allowed in last table.");
return;
}
} else {
ct->recirc_table = NX_CT_RECIRC_NONE;
}
ct->zone_src.field = mf_from_id(MFF_LOG_CT_ZONE);
ct->zone_src.ofs = 0;
ct->zone_src.n_bits = 16;
/* We do not support ALGs yet. */
ct->alg = 0;
/* CT only works with IP, so set up a prerequisite. */
struct expr *expr;
char *error;
expr = expr_parse_string("ip", ctx->symtab, &error);
ovs_assert(!error);
ctx->prereqs = expr_combine(EXPR_T_AND, ctx->prereqs, expr);
}
/* Parses 'prerequisite' as an expression in the context of 'ctx', then adds it
* as a conjunction with the existing 'ctx->prereqs'. */
static void
add_prerequisite(struct action_context *ctx, const char *prerequisite)
{
struct expr *expr;
char *error;
expr = expr_parse_string(prerequisite, ctx->ap->symtab, &error);
ovs_assert(!error);
ctx->prereqs = expr_combine(EXPR_T_AND, ctx->prereqs, expr);
}
static void
parse_actions(struct action_context *ctx)
{
/* "drop;" by itself is a valid (empty) set of actions, but it can't be
* combined with other actions because that doesn't make sense. */
if (ctx->lexer->token.type == LEX_T_ID
&& !strcmp(ctx->lexer->token.s, "drop")
&& lexer_lookahead(ctx->lexer) == LEX_T_SEMICOLON) {
lexer_get(ctx->lexer); /* Skip "drop". */
lexer_get(ctx->lexer); /* Skip ";". */
if (ctx->lexer->token.type != LEX_T_END) {
action_syntax_error(ctx, "expecting end of input");
}
return;
}
while (ctx->lexer->token.type != LEX_T_END) {
if (ctx->lexer->token.type != LEX_T_ID) {
action_syntax_error(ctx, NULL);
break;
}
enum lex_type lookahead = lexer_lookahead(ctx->lexer);
if (lookahead == LEX_T_EQUALS || lookahead == LEX_T_EXCHANGE
|| lookahead == LEX_T_LSQUARE) {
parse_set_action(ctx);
} else if (lexer_match_id(ctx->lexer, "next")) {
parse_next_action(ctx);
} else if (lexer_match_id(ctx->lexer, "output")) {
emit_resubmit(ctx, ctx->output_ptable);
} else if (lexer_match_id(ctx->lexer, "ip4.ttl")) {
if (lexer_match(ctx->lexer, LEX_T_DECREMENT)) {
struct expr *e = expr_parse_string("ip4", ctx->symtab,
&ctx->error);
ctx->prereqs = expr_combine(EXPR_T_AND, ctx->prereqs, e);
ofpact_put_DEC_TTL(ctx->ofpacts);
} else {
action_syntax_error(ctx, "expecting `--'");
}
} else if (lexer_match_id(ctx->lexer, "ct_next")) {
emit_ct(ctx, true, false);
} else if (lexer_match_id(ctx->lexer, "ct_commit")) {
emit_ct(ctx, false, true);
} else {
action_syntax_error(ctx, "expecting action");
}
if (!lexer_match(ctx->lexer, LEX_T_SEMICOLON)) {
action_syntax_error(ctx, "expecting ';'");
}
if (ctx->error) {
return;
}
}
}
/* Parses an assignment or exchange action. */
static void
parse_set_action(struct action_context *ctx)
{
struct expr *prereqs;
char *error;
error = expr_parse_assignment(ctx->lexer, ctx->symtab, ctx->ports,
ctx->ofpacts, &prereqs);
if (error) {
action_error(ctx, "%s", error);
free(error);
return;
}
ctx->prereqs = expr_combine(EXPR_T_AND, ctx->prereqs, prereqs);
}
