From: David Gibson
Extend the dynamic update protocol to expose the pif indices and names
from a running passt/pasta to the pesto tool. pesto records that data
and prints it out.
Signed-off-by: David Gibson
Reviewed-by: Laurent Vivier
[sbrivio: In read_pif_conf(), force a redundant termination of the
interface name, the existing check isn't obvious enough for static
checkers]
[sbrivio: Drop @resv_ left-over in description of struct
pesto_pif_info, reported by Jon Maloy]
[sbrivio: Fix minor nits reported by Laurent]
[sbrivio: Initialise struct pesto_pif_info in conf_send_rules() with
zeroes, otherwise the pif name might be seen as not terminated, and
we'll expose memory from the back-end]
[sbrivio: Fix conflicts in Makefile]
Signed-off-by: Stefano Brivio
---
common.h | 2 +
conf.c | 41 ++++++++++++++++
pesto.c | 134 ++++++++++++++++++++++++++++++++++++++++++++++++++++
pesto.h | 18 ++++++-
pif.h | 5 +-
serialise.c | 4 ++
serialise.h | 1 +
util.h | 2 -
8 files changed, 200 insertions(+), 7 deletions(-)
diff --git a/common.h b/common.h
index 4251781..68573b4 100644
--- a/common.h
+++ b/common.h
@@ -53,4 +53,6 @@ static inline const char *strerror_(int errnum)
#define strerror(x) @ "Don't call strerror() directly, use strerror_() instead"
+#define ARRAY_SIZE(a) ((int)(sizeof(a) / sizeof((a)[0])))
+
#endif /* COMMON_H */
diff --git a/conf.c b/conf.c
index 5ec0072..f8c2134 100644
--- a/conf.c
+++ b/conf.c
@@ -1927,6 +1927,43 @@ void conf(struct ctx *c, int argc, char **argv)
static void conf_accept(struct ctx *c);
+/**
+ * conf_send_rules() - Send current forwarding rules to config client (pesto)
+ * @c: Execution context
+ * @fd: Socket to the client
+ *
+ * Return: 0 on success, -1 on failure
+ *
+ * FIXME: So far only sends pif ids and names
+ */
+static int conf_send_rules(const struct ctx *c, int fd)
+{
+ unsigned pif;
+
+ for (pif = 0; pif < PIF_NUM_TYPES; pif++) {
+ struct pesto_pif_info info = { 0 };
+ int rc;
+
+ if (!c->fwd[pif])
+ continue;
+
+ assert(pif != PIF_NONE);
+
+ rc = snprintf(info.name, sizeof(info.name), "%s", pif_name(pif));
+ assert(rc >= 0 && (size_t)rc < sizeof(info.name));
+
+ if (write_u8(fd, pif) < 0)
+ return -1;
+ if (write_all_buf(fd, &info, sizeof(info)) < 0)
+ return -1;
+ }
+
+ if (write_u8(fd, PIF_NONE) < 0)
+ return -1;
+
+ return 0;
+}
+
/**
* conf_close() - Close configuration / control socket and clean up
* @c: Execution context
@@ -1970,6 +2007,7 @@ static void conf_accept(struct ctx *c)
struct pesto_hello hello = {
.magic = PESTO_SERVER_MAGIC,
.version = htonl(PESTO_PROTOCOL_VERSION),
+ .pif_name_size = htonl(PIF_NAME_SIZE),
};
union epoll_ref ref = { .type = EPOLL_TYPE_CONF };
struct ucred uc = { 0 };
@@ -2010,6 +2048,9 @@ retry:
"Warning: Using experimental unsupported configuration protocol");
}
+ if (conf_send_rules(c, fd) < 0)
+ goto fail;
+
return;
fail:
diff --git a/pesto.c b/pesto.c
index ab476c5..b33492a 100644
--- a/pesto.c
+++ b/pesto.c
@@ -60,6 +60,127 @@ static void usage(const char *name, FILE *f, int status)
exit(status);
}
+/* Maximum number of pifs with rule tables */
+#define MAX_PIFS 3
+
+struct pif_configuration {
+ uint8_t pif;
+ char name[PIF_NAME_SIZE];
+};
+
+struct configuration {
+ uint32_t npifs;
+ struct pif_configuration pif[MAX_PIFS];
+};
+
+/**
+ * pif_conf_by_num() - Find a pif's configuration by pif id
+ * @conf: Configuration description
+ * @pif: pif id
+ *
+ * Return: pointer to the pif_configuration for @pif, or NULL if not found
+ */
+static struct pif_configuration *pif_conf_by_num(struct configuration *conf,
+ uint8_t pif)
+{
+ unsigned i;
+
+ for (i = 0; i < conf->npifs; i++) {
+ if (conf->pif[i].pif == pif)
+ return &conf->pif[i];
+ }
+
+ return NULL;
+}
+
+/**
+ * pif_conf_by_name() - Find a pif's configuration by name
+ * @conf: Configuration description
+ * @name: Interface name
+ *
+ * Return: pif_configuration for pif named @name, or NULL if not found
+ */
+static struct pif_configuration *pif_conf_by_name(struct configuration *conf,
+ const char *name)
+{
+ unsigned i;
+
+ for (i = 0; i < conf->npifs; i++) {
+ if (strcmp(conf->pif[i].name, name) == 0)
+ return &conf->pif[i];
+ }
+
+ return NULL;
+}
+
+/**
+ * pesto_read_rules() - Read rulestate from passt/pasta
+ * @fd: Control socket
+ * @conf: Configuration description to update
+ */
+static bool read_pif_conf(int fd, struct configuration *conf)
+{
+ struct pif_configuration *pc;
+ struct pesto_pif_info info;
+ uint8_t pif;
+
+ if (read_u8(fd, &pif) < 0)
+ die("Error reading from control socket");
+
+ if (pif == PIF_NONE)
+ return false;
+
+ debug("Receiving config for PIF %"PRIu8, pif);
+
+ if (conf->npifs >= ARRAY_SIZE(conf->pif)) {
+ die("passt has more pifs than pesto can manage (max %d)",
+ ARRAY_SIZE(conf->pif));
+ }
+
+ pc = &conf->pif[conf->npifs];
+ pc->pif = pif;
+
+ if (read_all_buf(fd, &info, sizeof(info)) < 0)
+ die("Error reading from control socket");
+
+ if (info.name[sizeof(info.name)-1])
+ die("Interface name was not NULL terminated");
+ /* Redundant, to make static checkers happy */
+ info.name[sizeof(info.name) - 1] = '\0';
+
+ static_assert(sizeof(info.name) == sizeof(pc->name),
+ "Mismatching pif name lengths");
+ memcpy(pc->name, info.name, sizeof(pc->name));
+
+ debug("PIF %"PRIu8": %s", pc->pif, pc->name);
+
+ /* O(n^2), but n is bounded by MAX_PIFS */
+ if (pif_conf_by_num(conf, pc->pif))
+ die("Received duplicate interface identifier");
+
+ /* O(n^2), but n is bounded by MAX_PIFS */
+ if (pif_conf_by_name(conf, pc->name))
+ die("Received duplicate interface name");
+
+ conf->npifs++;
+ return true;
+}
+
+/**
+ * show_conf() - Show current configuration obtained from passt/pasta
+ * @conf: Configuration description
+ */
+static void show_conf(const struct configuration *conf)
+{
+ unsigned i;
+
+ for (i = 0; i < conf->npifs; i++) {
+ const struct pif_configuration *pc = &conf->pif[i];
+ printf(" %s\n", pc->name);
+ printf(" TBD\n");
+ }
+}
+
/**
* main() - Dynamic reconfiguration client main program
* @argc: Argument count
@@ -80,6 +201,7 @@ int main(int argc, char **argv)
{ 0 },
};
struct sockaddr_un a = { AF_UNIX, "" };
+ struct configuration conf = { 0 };
const char *optstring = "dh";
struct pesto_hello hello;
struct sock_fprog prog;
@@ -162,6 +284,18 @@ int main(int argc, char **argv)
"Warning: Using experimental protocol version, client and server must match\n");
}
+ if (ntohl(hello.pif_name_size) != PIF_NAME_SIZE) {
+ die("Server has unexpected pif name size (%"
+ PRIu32" not %"PRIu32 ")",
+ ntohl(hello.pif_name_size), PIF_NAME_SIZE);
+ }
+
+ while (read_pif_conf(s, &conf))
+ ;
+
+ printf("passt/pasta configuration (%s)\n", a.sun_path);
+ show_conf(&conf);
+
if (shutdown(s, SHUT_RDWR) < 0 || close(s) < 0)
die_perror("Error shutting down control socket");
diff --git a/pesto.h b/pesto.h
index 3c93d3e..fda0ef6 100644
--- a/pesto.h
+++ b/pesto.h
@@ -17,18 +17,32 @@
/* Version 0 is reserved for unreleased / unsupported experimental versions */
#define PESTO_PROTOCOL_VERSION 1
+/* Maximum size of a pif name, including \0 */
+#define PIF_NAME_SIZE (128)
+#define PIF_NONE 0
+
/**
* struct pesto_hello - Server introduction message
- * @magic: PESTO_SERVER_MAGIC
- * @version: Version number
+ * @magic: PESTO_SERVER_MAGIC
+ * @version: Version number
+ * @pif_name_size: Server's value for PIF_NAME_SIZE
*/
struct pesto_hello {
char magic[8];
uint32_t version;
+ uint32_t pif_name_size;
} __attribute__ ((__packed__));
static_assert(sizeof(PESTO_SERVER_MAGIC)
== sizeof(((struct pesto_hello *)0)->magic),
"PESTO_SERVER_MAGIC has wrong size");
+/**
+ * struct pesto_pif_info - Message with basic metadata about a pif
+ * @name: Name (\0 terminated)
+ */
+struct pesto_pif_info {
+ char name[PIF_NAME_SIZE];
+} __attribute__ ((__packed__));
+
#endif /* PESTO_H */
diff --git a/pif.h b/pif.h
index 553c742..48d4919 100644
--- a/pif.h
+++ b/pif.h
@@ -11,6 +11,7 @@
#include
+#include "pesto.h"
#include "epoll_type.h"
union inany_addr;
@@ -24,7 +25,7 @@ union sockaddr_inany;
*/
enum pif_type {
/* Invalid or not present pif */
- PIF_NONE = 0,
+ PIF_NONE_ = PIF_NONE,
/* Host socket interface */
PIF_HOST,
/* Qemu socket or namespace tuntap interface */
@@ -35,8 +36,6 @@ enum pif_type {
PIF_NUM_TYPES,
};
-/* Maximum size of a pif name, including \0 */
-#define PIF_NAME_SIZE (128)
extern const char pif_type_str[][PIF_NAME_SIZE];
static inline const char *pif_type(enum pif_type pt)
diff --git a/serialise.c b/serialise.c
index 346df99..e083112 100644
--- a/serialise.c
+++ b/serialise.c
@@ -121,6 +121,10 @@ int write_all_buf(int fd, const void *buf, size_t len)
return write_all_buf(fd, &beval, sizeof(beval)); \
}
+#define be8toh(x) (x)
+#define htobe8(x) (x)
+
+SERIALISE_UINT(8)
SERIALISE_UINT(32)
#undef SERIALISE_UINT
diff --git a/serialise.h b/serialise.h
index a88f3de..4714f4c 100644
--- a/serialise.h
+++ b/serialise.h
@@ -16,6 +16,7 @@ int write_all_buf(int fd, const void *buf, size_t len);
int read_u##bits(int fd, uint##bits##_t *val); \
int write_u##bits(int fd, uint##bits##_t val);
+SERIALISE_UINT_DECL(8)
SERIALISE_UINT_DECL(32)
#endif /* SERIALISE_H */
diff --git a/util.h b/util.h
index e90be47..c788382 100644
--- a/util.h
+++ b/util.h
@@ -87,8 +87,6 @@ void abort_with_msg(const char *fmt, ...)
#define V6 1
#define IP_VERSIONS 2
-#define ARRAY_SIZE(a) ((int)(sizeof(a) / sizeof((a)[0])))
-
#define foreach(item, array) \
for ((item) = (array); (item) - (array) < ARRAY_SIZE(array); (item)++)
--
2.43.0