From e20bef69ccc4a85ef62359ee539c9db2dbe09127 Mon Sep 17 00:00:00 2001
From: Ondrej Zajicek <santiago@crfreenet.org>
Date: Sat, 7 Jan 2023 20:18:44 +0100
Subject: [PATCH 1/3] Filter: Change linearization of branches in switch
instruction
Most branching instructions (FI_CONDITION, FI_AND, FI_OR) linearize its
branches in a recursive way, while FI_SWITCH branches are linearized
from parser even before the switch instruction is allocated.
Change linearization of FI_SWITCH branches to make it similar to other
branching instructions. This also fixes an issue with constant
switch evaluation, where linearized branch is mistaken for
non-linearized during switch construction.
Thanks to Jiten Kumar Pathy for the bugreport.
---
filter/config.Y | 7 +++----
filter/data.h | 1 +
filter/f-inst.c | 25 ++++++++++++++++++++++---
filter/tree.c | 20 ++++++++++++++++++++
4 files changed, 46 insertions(+), 7 deletions(-)
diff --git a/filter/config.Y b/filter/config.Y
index 68ee1a847..1d9d9aa97 100644
--- a/filter/config.Y
+++ b/filter/config.Y
@@ -676,16 +676,15 @@ switch_body: /* EMPTY */ { $$ = NULL; }
| switch_body switch_items ':' cmds_scoped {
/* Fill data fields */
struct f_tree *t;
- struct f_line *line = f_linearize($4, 0);
for (t = $2; t; t = t->left)
- t->data = line;
+ t->data = $4;
$$ = f_merge_items($1, $2);
}
| switch_body ELSECOL cmds_scoped {
struct f_tree *t = f_new_tree();
t->from.type = t->to.type = T_VOID;
t->right = t;
- t->data = f_linearize($3, 0);
+ t->data = $3;
$$ = f_merge_items($1, t);
}
;
@@ -972,7 +971,7 @@ cmd:
}
| function_call ';' { $$ = f_new_inst(FI_DROP_RESULT, $1); }
| CASE term '{' switch_body '}' {
- $$ = f_new_inst(FI_SWITCH, $2, build_tree($4));
+ $$ = f_new_inst(FI_SWITCH, $2, $4);
}
| dynamic_attr '.' EMPTY ';' { $$ = f_generate_empty($1); }
diff --git a/filter/data.h b/filter/data.h
index 5edeaedb7..700609e9d 100644
--- a/filter/data.h
+++ b/filter/data.h
@@ -198,6 +198,7 @@ struct f_trie_walk_state
struct f_tree *f_new_tree(void);
struct f_tree *build_tree(struct f_tree *);
const struct f_tree *find_tree(const struct f_tree *t, const struct f_val *val);
+const struct f_tree *find_tree_linear(const struct f_tree *t, const struct f_val *val);
int same_tree(const struct f_tree *t0, const struct f_tree *t2);
int tree_node_count(const struct f_tree *t);
void tree_format(const struct f_tree *t, buffer *buf);
diff --git a/filter/f-inst.c b/filter/f-inst.c
index 9a3a22abc..2d2a30e4f 100644
--- a/filter/f-inst.c
+++ b/filter/f-inst.c
@@ -1285,14 +1285,33 @@
FID_MEMBER(struct f_tree *, tree, [[!same_tree(f1->tree, f2->tree)]], "tree %p", item->tree);
+ FID_LINEARIZE_BODY()
+ /* Linearize all branches in switch */
+ struct f_inst *last_inst = NULL;
+ struct f_line *last_line = NULL;
+ for (struct f_tree *t = whati->tree; t; t = t->left)
+ {
+ if (t->data != last_inst)
+ {
+ last_inst = t->data;
+ last_line = f_linearize(t->data, 0);
+ }
+
+ t->data = last_line;
+ }
+
+ /* Balance the tree */
+ item->tree = build_tree(whati->tree);
+
FID_ITERATE_BODY()
- tree_walk(whati->tree, f_add_tree_lines, fit);
+ tree_walk(whati->tree, f_add_tree_lines, fit);
FID_INTERPRET_BODY()
- const struct f_tree *t = find_tree(tree, &v1);
+ /* In parse-time use find_tree_linear(), in runtime use find_tree() */
+ const struct f_tree *t = FID_HIC(,find_tree,find_tree_linear)(tree, &v1);
if (!t) {
v1.type = T_VOID;
- t = find_tree(tree, &v1);
+ t = FID_HIC(,find_tree,find_tree_linear)(tree, &v1);
if (!t) {
debug( "No else statement?\n");
FID_HIC(,break,return NULL);
diff --git a/filter/tree.c b/filter/tree.c
index 97bf7dae5..25cf93e49 100644
--- a/filter/tree.c
+++ b/filter/tree.c
@@ -38,6 +38,26 @@ find_tree(const struct f_tree *t, const struct f_val *val)
return find_tree(t->left, val);
}
+/**
+ * find_tree_linear
+ * @t: tree to search in
+ * @val: value to find
+ *
+ * Search for given value in the degenerated linear tree, which is generated by
+ * parser before build_tree() is applied. The tree is not sorted and all nodes
+ * are linked by left ptr.
+ */
+const struct f_tree *
+find_tree_linear(const struct f_tree *t, const struct f_val *val)
+{
+ for (; t; t = t->left)
+ if ((val_compare(&(t->from), val) != 1) &&
+ (val_compare(&(t->to), val) != -1))
+ return t;
+
+ return NULL;
+}
+
static struct f_tree *
build_tree_rec(struct f_tree **buf, int l, int h)
{
From 64a2b7aaa303be0b407508747bfc96c1c656f1e2 Mon Sep 17 00:00:00 2001
From: Mike Crute <mike@crute.us>
Date: Thu, 12 Jan 2023 17:40:53 +0100
Subject: [PATCH 2/3] Log message before aborting
Log message before aborting due to watchdog timeout. We have to use
async-safe write to debug log, as it is done in signal handler.
Minor changes from committer.
---
lib/birdlib.h | 1 +
sysdep/unix/io.c | 2 ++
sysdep/unix/log.c | 22 ++++++++++++++++++++++
3 files changed, 25 insertions(+)
diff --git a/lib/birdlib.h b/lib/birdlib.h
index 81d4908ac..e03bd0b2f 100644
--- a/lib/birdlib.h
+++ b/lib/birdlib.h
@@ -160,6 +160,7 @@ void bug(const char *msg, ...) NORET;
#define L_BUG "\011" /* BIRD bugs */
void debug(const char *msg, ...); /* Printf to debug output */
+void debug_safe(const char *msg); /* Printf to debug output, async-safe */
/* Debugging */
diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index 810e782d9..e131ca41f 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -2128,6 +2128,8 @@ watchdog_sigalrm(int sig UNUSED)
config->latency_limit = 0xffffffff;
io_update_time();
+ debug_safe("Watchdog timer timed out\n");
+
/* We want core dump */
abort();
}
diff --git a/sysdep/unix/log.c b/sysdep/unix/log.c
index 4e9df069e..53122aee3 100644
--- a/sysdep/unix/log.c
+++ b/sysdep/unix/log.c
@@ -31,6 +31,7 @@
#include "lib/lists.h"
#include "sysdep/unix/unix.h"
+static int dbg_fd = -1;
static FILE *dbgf;
static list *current_log_list;
static char *current_syslog_name; /* NULL -> syslog closed */
@@ -324,6 +325,21 @@ debug(const char *msg, ...)
va_end(args);
}
+/**
+ * debug_safe - async-safe write to debug output
+ * @msg: a string message
+ *
+ * This function prints the message @msg to the debugging output in a
+ * way that is async safe and can be used in signal handlers. No newline
+ * character is appended.
+ */
+void
+debug_safe(const char *msg)
+{
+ if (dbg_fd >= 0)
+ write(dbg_fd, msg, strlen(msg));
+}
+
static list *
default_log_list(int initial, const char **syslog_name)
{
@@ -422,8 +438,10 @@ done:
void
log_init_debug(char *f)
{
+ dbg_fd = -1;
if (dbgf && dbgf != stderr)
fclose(dbgf);
+
if (!f)
dbgf = NULL;
else if (!*f)
@@ -434,6 +452,10 @@ log_init_debug(char *f)
fprintf(stderr, "bird: Unable to open debug file %s: %s\n", f, strerror(errno));
exit(1);
}
+
if (dbgf)
+ {
setvbuf(dbgf, NULL, _IONBF, 0);
+ dbg_fd = fileno(dbgf);
+ }
}
From 7fb23041a52d01754c53ba963e2282e524813364 Mon Sep 17 00:00:00 2001
From: Ondrej Zajicek <santiago@crfreenet.org>
Date: Fri, 13 Jan 2023 13:17:46 +0100
Subject: [PATCH 3/3] BSD: Add support for kernel route metric
Add support for kernel route metric/priority, exported as krt_metric
attribute, like in Linux. This should also fix issues with overwriting
or removing system routes.
---
sysdep/bsd/krt-sock.Y | 10 +++++++++-
sysdep/bsd/krt-sock.c | 39 +++++++++++++++++++++++++++++++++++++--
sysdep/bsd/krt-sys.h | 2 ++
3 files changed, 48 insertions(+), 3 deletions(-)
diff --git a/sysdep/bsd/krt-sock.Y b/sysdep/bsd/krt-sock.Y
index 8581bd43b..a03d6df5f 100644
--- a/sysdep/bsd/krt-sock.Y
+++ b/sysdep/bsd/krt-sock.Y
@@ -10,7 +10,7 @@ CF_HDR
CF_DECLS
-CF_KEYWORDS(KERNEL, TABLE)
+CF_KEYWORDS(KERNEL, TABLE, METRIC)
CF_GRAMMAR
@@ -25,6 +25,14 @@ kern_sys_item:
THIS_KRT->sys.table_id = $3;
}
+ | METRIC expr {
+ if ($2 && !krt_max_metric)
+ cf_error("Kernel route metric not supported");
+ if ($2 > krt_max_metric)
+ cf_error("Kernel table id must be in range 0-%u", krt_max_metric);
+
+ THIS_KRT->sys.metric = $2;
+ }
;
CF_CODE
diff --git a/sysdep/bsd/krt-sock.c b/sysdep/bsd/krt-sock.c
index 47f5cf595..540c246f3 100644
--- a/sysdep/bsd/krt-sock.c
+++ b/sysdep/bsd/krt-sock.c
@@ -47,6 +47,11 @@ const int rt_default_ecmp = 0;
* table_id is specified explicitly as sysctl scan argument, while in FreeBSD it
* is handled implicitly by changing default table using setfib() syscall.
*
+ * OpenBSD allows to use route metric. The behavior is controlled by these macro
+ * KRT_USE_METRIC, which enables use of rtm_priority in route send/recevive.
+ * There is also KRT_DEFAULT_METRIC and KRT_MAX_METRIC for default and maximum
+ * metric values.
+ *
* KRT_SHARED_SOCKET - use shared kernel socked instead of one for each krt_proto
* KRT_USE_SETFIB_SCAN - use setfib() for sysctl() route scan
* KRT_USE_SETFIB_SOCK - use SO_SETFIB socket option for kernel sockets
@@ -63,6 +68,9 @@ const int rt_default_ecmp = 0;
#ifdef __OpenBSD__
#define KRT_MAX_TABLES (RT_TABLEID_MAX+1)
+#define KRT_USE_METRIC
+#define KRT_MAX_METRIC 255
+#define KRT_DEFAULT_METRIC 56
#define KRT_SHARED_SOCKET
#define KRT_USE_SYSCTL_7
#endif
@@ -71,6 +79,14 @@ const int rt_default_ecmp = 0;
#define KRT_MAX_TABLES 1
#endif
+#ifndef KRT_MAX_METRIC
+#define KRT_MAX_METRIC 0
+#endif
+
+#ifndef KRT_DEFAULT_METRIC
+#define KRT_DEFAULT_METRIC 0
+#endif
+
/* Dynamic max number of tables */
@@ -143,6 +159,10 @@ static struct krt_proto *krt_table_map[KRT_MAX_TABLES][2];
#endif
+/* Make it available to parser code */
+const uint krt_max_metric = KRT_MAX_METRIC;
+
+
/* Route socket message processing */
int
@@ -231,6 +251,10 @@ krt_send_route(struct krt_proto *p, int cmd, rte *e)
msg.rtm.rtm_tableid = KRT_CF->sys.table_id;
#endif
+#ifdef KRT_USE_METRIC
+ msg.rtm.rtm_priority = KRT_CF->sys.metric;
+#endif
+
#ifdef RTF_REJECT
if(a->dest == RTD_UNREACHABLE)
msg.rtm.rtm_flags |= RTF_REJECT;
@@ -586,7 +610,7 @@ krt_read_route(struct ks_msg *msg, struct krt_proto *p, int scan)
e = rte_get_temp(&a, p->p.main_source);
e->net = net;
- ea_list *ea = alloca(sizeof(ea_list) + 1 * sizeof(eattr));
+ ea_list *ea = alloca(sizeof(ea_list) + 2 * sizeof(eattr));
*ea = (ea_list) { .count = 1, .next = e->attrs->eattrs };
e->attrs->eattrs = ea;
@@ -596,6 +620,15 @@ krt_read_route(struct ks_msg *msg, struct krt_proto *p, int scan)
.u.data = src2,
};
+#ifdef KRT_USE_METRIC
+ ea->count++;
+ ea->attrs[1] = (eattr) {
+ .id = EA_KRT_METRIC,
+ .type = EAF_TYPE_INT,
+ .u.data = msg->rtm.rtm_priority,
+ };
+#endif
+
if (scan)
krt_got_route(p, e, src);
else
@@ -1155,7 +1188,7 @@ krt_sys_shutdown(struct krt_proto *p)
int
krt_sys_reconfigure(struct krt_proto *p UNUSED, struct krt_config *n, struct krt_config *o)
{
- return n->sys.table_id == o->sys.table_id;
+ return (n->sys.table_id == o->sys.table_id) && (n->sys.metric == o->sys.metric);
}
void
@@ -1168,11 +1201,13 @@ krt_sys_preconfig(struct config *c UNUSED)
void krt_sys_init_config(struct krt_config *c)
{
c->sys.table_id = 0; /* Default table */
+ c->sys.metric = KRT_DEFAULT_METRIC;
}
void krt_sys_copy_config(struct krt_config *d, struct krt_config *s)
{
d->sys.table_id = s->sys.table_id;
+ d->sys.metric = s->sys.metric;
}
diff --git a/sysdep/bsd/krt-sys.h b/sysdep/bsd/krt-sys.h
index 575018843..198373c09 100644
--- a/sysdep/bsd/krt-sys.h
+++ b/sysdep/bsd/krt-sys.h
@@ -32,9 +32,11 @@ static inline void kif_sys_copy_config(struct kif_config *d UNUSED, struct kif_c
/* Kernel routes */
extern uint krt_max_tables;
+extern const uint krt_max_metric;
struct krt_params {
int table_id; /* Kernel table ID we sync with */
+ u32 metric; /* Kernel metric used for all routes */
};
struct krt_state {