Add a control socket to passt/pasta for updating configuration at runtime.
Add a tool (pesto) for communicating with the control socket.
For now this is a stub implementation that forms the connection and sends
some version information, but nothing more.
Example:
./pasta --debug --config-net -c /tmp/pasta.conf -t none
./pesto /tmp/pasta.conf
Signed-off-by: Stefano Brivio
[dwg: Based on an early draft from Stefano]
Signed-off-by: David Gibson
---
.gitignore | 2 +
Makefile | 30 +++++++----
common.h | 14 +++++
conf.c | 150 ++++++++++++++++++++++++++++++++++++++++++++++++++-
conf.h | 2 +
epoll_type.h | 4 ++
log.c | 1 +
passt.1 | 5 ++
passt.c | 9 ++++
passt.h | 6 +++
pesto.1 | 46 ++++++++++++++++
pesto.c | 113 ++++++++++++++++++++++++++++++++++++++
pesto.h | 34 ++++++++++++
serialise.c | 3 ++
util.h | 3 --
15 files changed, 407 insertions(+), 15 deletions(-)
create mode 100644 common.h
create mode 100644 pesto.1
create mode 100644 pesto.c
create mode 100644 pesto.h
diff --git a/.gitignore b/.gitignore
index 3c16adc7..3e40d9f7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,9 +4,11 @@
/pasta
/pasta.avx2
/passt-repair
+/pesto
/qrap
/pasta.1
/seccomp.h
+/seccomp_pesto.h
/seccomp_repair.h
/c*.json
README.plain.md
diff --git a/Makefile b/Makefile
index 5b6891d7..d085c9c1 100644
--- a/Makefile
+++ b/Makefile
@@ -44,17 +44,19 @@ PASST_SRCS = arch.c arp.c checksum.c conf.c dhcp.c dhcpv6.c epoll_ctl.c \
udp.c udp_flow.c udp_vu.c util.c vhost_user.c virtio.c vu_common.c
QRAP_SRCS = qrap.c
PASST_REPAIR_SRCS = passt-repair.c
-SRCS = $(PASST_SRCS) $(QRAP_SRCS) $(PASST_REPAIR_SRCS)
+PESTO_SRCS = pesto.c serialise.c
+SRCS = $(PASST_SRCS) $(QRAP_SRCS) $(PASST_REPAIR_SRCS) $(PESTO_SRCS)
-MANPAGES = passt.1 pasta.1 qrap.1 passt-repair.1
+MANPAGES = passt.1 pasta.1 pesto.1 qrap.1 passt-repair.1
+PESTO_HEADERS = common.h pesto.h serialise.h
PASST_HEADERS = arch.h arp.h checksum.h conf.h dhcp.h dhcpv6.h epoll_ctl.h \
flow.h fwd.h flow_table.h icmp.h icmp_flow.h inany.h iov.h ip.h \
isolation.h lineread.h log.h migrate.h ndp.h netlink.h packet.h \
- passt.h pasta.h pcap.h pif.h repair.h serialise.h siphash.h tap.h tcp.h \
- tcp_buf.h tcp_conn.h tcp_internal.h tcp_splice.h tcp_vu.h udp.h \
- udp_flow.h udp_internal.h udp_vu.h util.h vhost_user.h virtio.h \
- vu_common.h
+ passt.h pasta.h pcap.h pif.h repair.h siphash.h tap.h tcp.h tcp_buf.h \
+ tcp_conn.h tcp_internal.h tcp_splice.h tcp_vu.h udp.h udp_flow.h \
+ udp_internal.h udp_vu.h util.h vhost_user.h virtio.h vu_common.h \
+ $(PESTO_HEADERS)
HEADERS = $(PASST_HEADERS) seccomp.h
C := \#include \nint main(){int a=getrandom(0, 0, 0);}
@@ -75,9 +77,9 @@ mandir ?= $(datarootdir)/man
man1dir ?= $(mandir)/man1
ifeq ($(TARGET_ARCH),x86_64)
-BIN := passt passt.avx2 pasta pasta.avx2 qrap passt-repair
+BIN := passt passt.avx2 pasta pasta.avx2 qrap passt-repair pesto
else
-BIN := passt pasta qrap passt-repair
+BIN := passt pasta qrap passt-repair pesto
endif
all: $(BIN) $(MANPAGES) docs
@@ -91,6 +93,9 @@ seccomp.h: seccomp.sh $(PASST_SRCS) $(PASST_HEADERS)
seccomp_repair.h: seccomp.sh $(PASST_REPAIR_SRCS)
@ ARCH="$(TARGET_ARCH)" CC="$(CC)" ./seccomp.sh seccomp_repair.h $(PASST_REPAIR_SRCS)
+seccomp_pesto.h: seccomp.sh $(PESTO_SRCS)
+ @ ARCH="$(TARGET_ARCH)" CC="$(CC)" ./seccomp.sh seccomp_pesto.h $(PESTO_SRCS)
+
passt: $(PASST_SRCS) $(HEADERS)
$(CC) $(FLAGS) $(CFLAGS) $(CPPFLAGS) $(PASST_SRCS) -o passt $(LDFLAGS)
@@ -110,6 +115,9 @@ qrap: $(QRAP_SRCS) passt.h
passt-repair: $(PASST_REPAIR_SRCS) seccomp_repair.h
$(CC) $(FLAGS) $(CFLAGS) $(CPPFLAGS) $(PASST_REPAIR_SRCS) -o passt-repair $(LDFLAGS)
+pesto: $(PESTO_SRCS) $(PESTO_HEADERS) seccomp_pesto.h
+ $(CC) $(FLAGS) $(CFLAGS) $(CPPFLAGS) $(PESTO_SRCS) -o pesto $(LDFLAGS)
+
valgrind: EXTRA_SYSCALLS += rt_sigprocmask rt_sigtimedwait rt_sigaction \
rt_sigreturn getpid gettid kill clock_gettime \
mmap|mmap2 munmap open unlink gettimeofday futex \
@@ -119,7 +127,7 @@ valgrind: all
.PHONY: clean
clean:
- $(RM) $(BIN) *~ *.o seccomp.h seccomp_repair.h pasta.1 \
+ $(RM) $(BIN) *~ *.o seccomp.h seccomp_repair.h seccomp_pesto.h pasta.1 \
passt.tar passt.tar.gz *.deb *.rpm \
passt.pid README.plain.md
@@ -173,11 +181,11 @@ docs: README.md
done < README.md; \
) > README.plain.md
-clang-tidy: $(PASST_SRCS)
+clang-tidy: $(PASST_SRCS) $(PESTO_SRCS)
clang-tidy $^ -- $(filter-out -pie,$(FLAGS) $(CFLAGS) $(CPPFLAGS)) \
-DCLANG_TIDY_58992
-cppcheck: $(PASST_SRCS) $(HEADERS)
+cppcheck: $(PASST_SRCS) $(PESTO_SRCS) $(HEADERS)
if cppcheck --check-level=exhaustive /dev/null > /dev/null 2>&1; then \
CPPCHECK_EXHAUSTIVE="--check-level=exhaustive"; \
else \
diff --git a/common.h b/common.h
new file mode 100644
index 00000000..76a95609
--- /dev/null
+++ b/common.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright Red Hat
+ * Author: David Gibson
+ *
+ * Definitions used by both passt/pasta and other tools
+ */
+
+#ifndef COMMON_H
+#define COMMON_H
+
+/* FPRINTF() intentionally silences cert-err33-c clang-tidy warnings */
+#define FPRINTF(f, ...) (void)fprintf(f, __VA_ARGS__)
+
+#endif /* _COMMON_H */
diff --git a/conf.c b/conf.c
index d4c2a013..5e8bc665 100644
--- a/conf.c
+++ b/conf.c
@@ -35,6 +35,7 @@
#include
#include
+#include "common.h"
#include "util.h"
#include "ip.h"
#include "passt.h"
@@ -47,6 +48,10 @@
#include "isolation.h"
#include "log.h"
#include "vhost_user.h"
+#include "epoll_ctl.h"
+#include "conf.h"
+#include "pesto.h"
+#include "serialise.h"
#define NETNS_RUN_DIR "/run/netns"
@@ -888,6 +893,7 @@ static void usage(const char *name, FILE *f, int status)
" --runas UID|UID:GID Run as given UID, GID, which can be\n"
" numeric, or login and group names\n"
" default: drop to user \"nobody\"\n"
+ " -c, --conf-path PATH Configuration socket path\n"
" -h, --help Display this help message and exit\n"
" --version Show version and exit\n");
@@ -1425,6 +1431,17 @@ static void conf_open_files(struct ctx *c)
if (c->pidfile_fd < 0)
die_perror("Couldn't open PID file %s", c->pidfile);
}
+
+ c->fd_conf = -1;
+ if (*c->conf_path) {
+ c->fd_conf_listen = sock_unix(c->conf_path);
+ if (c->fd_conf_listen < 0) {
+ die_perror("Couldn't open control socket %s",
+ c->conf_path);
+ }
+ } else {
+ c->fd_conf_listen = -1;
+ }
}
/**
@@ -1460,6 +1477,25 @@ fail:
die("Invalid MAC address: %s", str);
}
+/**
+ * conf_sock_listen() - Start listening for connections on configuration socket
+ * @c: Execution context
+ */
+static void conf_sock_listen(const struct ctx *c)
+{
+ union epoll_ref ref = { .type = EPOLL_TYPE_CONF_LISTEN };
+
+ if (c->fd_conf_listen < 0)
+ return;
+
+ if (listen(c->fd_conf_listen, 0))
+ die_perror("Couldn't listen on configuration socket");
+
+ ref.fd = c->fd_conf_listen;
+ if (epoll_add(c->epollfd, EPOLLIN | EPOLLET, ref))
+ die_perror("Couldn't add configuration socket to epoll");
+}
+
/**
* conf() - Process command-line arguments and set configuration
* @c: Execution context
@@ -1542,9 +1578,10 @@ void conf(struct ctx *c, int argc, char **argv)
{"migrate-exit", no_argument, NULL, 29 },
{"migrate-no-linger", no_argument, NULL, 30 },
{"stats", required_argument, NULL, 31 },
+ {"conf-path", required_argument, NULL, 'c' },
{ 0 },
};
- const char *optstring = "+dqfel:hs:F:I:p:P:m:a:n:M:g:i:o:D:S:H:461t:u:T:U:";
+ const char *optstring = "+dqfel:hs:c:F:I:p:P:m:a:n:M:g:i:o:D:S:H:461t:u:T:U:";
const char *logname = (c->mode == MODE_PASTA) ? "pasta" : "passt";
char userns[PATH_MAX] = { 0 }, netns[PATH_MAX] = { 0 };
bool copy_addrs_opt = false, copy_routes_opt = false;
@@ -1808,6 +1845,13 @@ void conf(struct ctx *c, int argc, char **argv)
c->fd_tap = -1;
break;
+ case 'c':
+ ret = snprintf(c->conf_path, sizeof(c->conf_path), "%s",
+ optarg);
+ if (ret <= 0 || ret >= (int)sizeof(c->sock_path))
+ die("Invalid configuration path: %s", optarg);
+ c->fd_conf_listen = c->fd_conf = -1;
+ break;
case 'F':
errno = 0;
fd_tap_opt = strtol(optarg, NULL, 0);
@@ -2252,4 +2296,108 @@ void conf(struct ctx *c, int argc, char **argv)
if (!c->quiet)
conf_print(c);
+
+ conf_sock_listen(c);
+}
+
+/**
+ * conf_listen_handler() - Handle events on configuration listening socket
+ * @c: Execution context
+ * @events: epoll events
+ */
+void conf_listen_handler(struct ctx *c, uint32_t events)
+{
+ struct pesto_hello hello = {
+ .magic = PESTO_SERVER_MAGIC,
+ .version = htonl(PESTO_PROTOCOL_VERSION),
+ };
+ union epoll_ref ref = { .type = EPOLL_TYPE_CONF };
+ struct ucred uc = { 0 };
+ socklen_t len = sizeof(uc);
+ int fd, rc;
+
+ if (events != EPOLLIN) {
+ err("Unexpected event 0x%04x on configuration socket", events);
+ return;
+ }
+
+ fd = accept4(c->fd_conf_listen, NULL, NULL, SOCK_NONBLOCK);
+ if (fd < 0) {
+ warn_perror("accept4() on configuration listening socket");
+ return;
+ }
+
+ if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &uc, &len) < 0)
+ warn_perror("Can't get configuration client credentials");
+
+ /* Another client is already connected: accept and close right away. */
+ if (c->fd_conf != -1) {
+ info("Discarding configuration client, PID %i", uc.pid);
+ goto fail;
+ }
+
+ ref.fd = fd;
+ rc = epoll_add(c->epollfd, EPOLLIN | EPOLLET, ref);
+ if (rc < 0) {
+ warn_perror("epoll_ctl() on configuration socket");
+ goto fail;
+ }
+
+ rc = write_all_buf(fd, &hello, sizeof(hello));
+ if (rc < 0) {
+ warn_perror("Error writing configuration protocol hello");
+ goto fail;
+ }
+
+ c->fd_conf = fd;
+ info("Accepted configuration client, PID %i", uc.pid);
+ if (!PESTO_PROTOCOL_VERSION) {
+ warn(
+"Warning: Using experimental unsupported configuration protocol");
+ }
+
+ return;
+
+fail:
+ close(fd);
+}
+
+/**
+ * conf_handler() - Handle events on configuration socket
+ * @c: Execution context
+ * @events: epoll events
+ */
+void conf_handler(struct ctx *c, uint32_t events)
+{
+ if (events & EPOLLIN) {
+ char discard[BUFSIZ];
+ ssize_t n;
+
+ do {
+ n = read(c->fd_conf, discard, sizeof(discard));
+ if (n > 0)
+ debug("Discarded %zd bytes of config data", n);
+ } while (n > 0);
+ if (n == 0) {
+ debug("Configuration client EOF");
+ goto close;
+ }
+ if (errno != EAGAIN && errno != EWOULDBLOCK) {
+ err_perror("Error reading config data");
+ goto close;
+ }
+ }
+
+ if (events & EPOLLHUP) {
+ debug("Configuration client hangup");
+ goto close;
+ }
+
+ return;
+
+close:
+ debug("Closing configuration socket");
+ epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_conf, NULL);
+ close(c->fd_conf);
+ c->fd_conf = -1;
}
diff --git a/conf.h b/conf.h
index b45ad746..16f97189 100644
--- a/conf.h
+++ b/conf.h
@@ -8,5 +8,7 @@
enum passt_modes conf_mode(int argc, char *argv[]);
void conf(struct ctx *c, int argc, char **argv);
+void conf_listen_handler(struct ctx *c, uint32_t events);
+void conf_handler(struct ctx *c, uint32_t events);
#endif /* CONF_H */
diff --git a/epoll_type.h b/epoll_type.h
index a90ffb67..061325aa 100644
--- a/epoll_type.h
+++ b/epoll_type.h
@@ -46,6 +46,10 @@ enum epoll_type {
EPOLL_TYPE_REPAIR,
/* Netlink neighbour subscription socket */
EPOLL_TYPE_NL_NEIGH,
+ /* Configuration listening socket */
+ EPOLL_TYPE_CONF_LISTEN,
+ /* Configuration socket */
+ EPOLL_TYPE_CONF,
EPOLL_NUM_TYPES,
};
diff --git a/log.c b/log.c
index 21e3673e..99404e25 100644
--- a/log.c
+++ b/log.c
@@ -26,6 +26,7 @@
#include
#include
+#include "common.h"
#include "linux_dep.h"
#include "log.h"
#include "util.h"
diff --git a/passt.1 b/passt.1
index 13e8df9d..32d70c8d 100644
--- a/passt.1
+++ b/passt.1
@@ -127,6 +127,11 @@ login name and group name can be passed. This requires privileges (either
initial effective UID 0 or CAP_SETUID capability) to work.
Default is to change to user \fInobody\fR if started as root.
+.TP
+.BR \-c ", " \-\-conf-path " " \fIpath " " (EXPERIMENTAL)
+Path for configuration and control socket used by \fBpesto\fR(1) to
+dynamically update passt or pasta's configuration.
+
.TP
.BR \-h ", " \-\-help
Display a help message and exit.
diff --git a/passt.c b/passt.c
index f84419c7..d37beef3 100644
--- a/passt.c
+++ b/passt.c
@@ -36,6 +36,7 @@
#include
#include
+#include "common.h"
#include "util.h"
#include "passt.h"
#include "dhcp.h"
@@ -80,6 +81,8 @@ char *epoll_type_str[] = {
[EPOLL_TYPE_REPAIR_LISTEN] = "TCP_REPAIR helper listening socket",
[EPOLL_TYPE_REPAIR] = "TCP_REPAIR helper socket",
[EPOLL_TYPE_NL_NEIGH] = "netlink neighbour notifier socket",
+ [EPOLL_TYPE_CONF_LISTEN] = "configuration listening socket",
+ [EPOLL_TYPE_CONF] = "configuration socket",
};
static_assert(ARRAY_SIZE(epoll_type_str) == EPOLL_NUM_TYPES,
"epoll_type_str[] doesn't match enum epoll_type");
@@ -303,6 +306,12 @@ static void passt_worker(void *opaque, int nfds, struct epoll_event *events)
case EPOLL_TYPE_NL_NEIGH:
nl_neigh_notify_handler(c);
break;
+ case EPOLL_TYPE_CONF_LISTEN:
+ conf_listen_handler(c, eventmask);
+ break;
+ case EPOLL_TYPE_CONF:
+ conf_handler(c, eventmask);
+ break;
default:
/* Can't happen */
assert(0);
diff --git a/passt.h b/passt.h
index 62b8dcdf..c38bb5ae 100644
--- a/passt.h
+++ b/passt.h
@@ -158,6 +158,7 @@ struct ip6_ctx {
* @foreground: Run in foreground, don't log to stderr by default
* @nofile: Maximum number of open files (ulimit -n)
* @sock_path: Path for UNIX domain socket
+ * @conf_path: Path for configuration UNIX domain socket
* @repair_path: TCP_REPAIR helper path, can be "none", empty for default
* @pcap: Path for packet capture file
* @pidfile: Path to PID file, empty string if not configured
@@ -169,6 +170,8 @@ struct ip6_ctx {
* @epollfd: File descriptor for epoll instance
* @fd_tap_listen: File descriptor for listening AF_UNIX socket, if any
* @fd_tap: AF_UNIX socket, tuntap device, or pre-opened socket
+ * @fd_conf_listen: Listening configuration socket, if any
+ * @fd_conf: Configuration socket, if any
* @fd_repair_listen: File descriptor for listening TCP_REPAIR socket, if any
* @fd_repair: Connected AF_UNIX socket for TCP_REPAIR helper
* @our_tap_mac: Pasta/passt's MAC on the tap link
@@ -223,6 +226,7 @@ struct ctx {
int foreground;
int nofile;
char sock_path[UNIX_PATH_MAX];
+ char conf_path[UNIX_PATH_MAX];
char repair_path[UNIX_PATH_MAX];
char pcap[PATH_MAX];
@@ -240,6 +244,8 @@ struct ctx {
int epollfd;
int fd_tap_listen;
int fd_tap;
+ int fd_conf_listen;
+ int fd_conf;
int fd_repair_listen;
int fd_repair;
unsigned char our_tap_mac[ETH_ALEN];
diff --git a/pesto.1 b/pesto.1
new file mode 100644
index 00000000..338fb8a6
--- /dev/null
+++ b/pesto.1
@@ -0,0 +1,46 @@
+.\" SPDX-License-Identifier: GPL-2.0-or-later
+.\" Copyright Red Hat
+.\" Author: David Gibson
+.TH pesto 1
+
+.SH NAME
+.B pesto
+\- Configure a running \fBpasst\fR(1) or \fBpasta\fR(1) instance.
+
+.SH SYNOPSIS
+.B pesto
+\fIPATH\fR
+
+.SH DESCRIPTION
+
+.B pesto
+is an experimental client to view and update the port forwarding
+configuration of a running \fBpasst\fR(1) or \fBpasta\fR(1) instance.
+
+\fIPATH\fR gives the path to the UNIX domain socket created by
+\fBpasst\fR or \fBpasta\fR. It should match the \fB-c\fR command line
+option given to that instance.
+
+.SH AUTHORS
+
+Stefano Brivio ,
+David Gibson .
+
+.SH REPORTING BUGS
+
+Please report issues on the bug tracker at https://bugs.passt.top/, or
+send a message to the passt-user@passt.top mailing list, see
+https://lists.passt.top/.
+
+.SH COPYRIGHT
+
+Copyright Red Hat
+
+\fBpesto\fR is free software: you can redistribute them and/or modify
+them under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or (at
+your option) any later version.
+
+.SH SEE ALSO
+
+\fBpasst\fR(1), \fBpasta\fR(1), \fBunix\fR(7).
diff --git a/pesto.c b/pesto.c
new file mode 100644
index 00000000..6d066084
--- /dev/null
+++ b/pesto.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/* PESTO - Programmable Extensible Socket Translation Orchestrator
+ * front-end for passt(1) and pasta(1) forwarding configuration
+ *
+ * pesto.c - Main program (it's not actually extensible)
+ *
+ * Copyright (c) 2026 Red Hat GmbH
+ * Author: Stefano Brivio
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include
+#include
+#include
+#include
+
+#include "common.h"
+#include "seccomp_pesto.h"
+#include "serialise.h"
+#include "pesto.h"
+
+#define die(...) \
+ do { \
+ FPRINTF(stderr, __VA_ARGS__); \
+ FPRINTF(stderr, "\n"); \
+ exit(EXIT_FAILURE); \
+ } while (0)
+
+/**
+ * main() - Entry point and whole program with loop
+ * @argc: Argument count
+ * @argv: Arguments: socket path, operation, port specifiers
+ *
+ * Return: 0 on success, won't return on failure
+ *
+ * #syscalls:pesto connect write close exit_group fstat brk
+ * #syscalls:pesto socket s390x:socketcall i686:socketcall
+ * #syscalls:pesto recvfrom recvmsg arm:recv ppc64le:recv
+ * #syscalls:pesto sendto sendmsg arm:send ppc64le:send
+ */
+int main(int argc, char **argv)
+{
+ struct sockaddr_un a = { AF_UNIX, "" };
+ struct pesto_hello hello;
+ struct sock_fprog prog;
+ uint32_t s_version;
+ int ret, s;
+
+ prctl(PR_SET_DUMPABLE, 0);
+
+ prog.len = (unsigned short)sizeof(filter_pesto) /
+ sizeof(filter_pesto[0]);
+ prog.filter = filter_pesto;
+ if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) ||
+ prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog))
+ die("Failed to apply seccomp filter");
+
+ if (argc < 2)
+ die("Usage: %s CONTROLPATH", argv[0]);
+
+ if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+ die("Failed to create AF_UNIX socket: %s", strerror(errno));
+
+ ret = snprintf(a.sun_path, sizeof(a.sun_path), "%s", argv[1]);
+ if (ret <= 0 || ret >= (int)sizeof(a.sun_path))
+ die("Invalid socket path \"%s\"", argv[1]);
+
+ ret = connect(s, (struct sockaddr *)&a, sizeof(a));
+ if (ret < 0) {
+ die("Failed to connect to %s: %s",
+ a.sun_path, strerror(errno));
+ }
+
+ ret = read_all_buf(s, &hello, sizeof(hello));
+ if (ret < 0)
+ die("Couldn't read server greeting: %s", strerror(errno));
+
+ if (memcmp(hello.magic, PESTO_SERVER_MAGIC, sizeof(hello.magic)))
+ die("Bad magic number from server");
+
+ s_version = ntohl(hello.version);
+
+ if (s_version > PESTO_PROTOCOL_VERSION) {
+ die("Unknown server protocol version %"PRIu32" > %"PRIu32"\n",
+ s_version, PESTO_PROTOCOL_VERSION);
+ }
+
+ /* cppcheck-suppress knownConditionTrueFalse */
+ if (!s_version) {
+ if (PESTO_PROTOCOL_VERSION)
+ die("Unsupported experimental server protocol");
+ FPRINTF(stderr,
+"Warning: Using experimental protocol version, client and server must match\n");
+ }
+
+ exit(0);
+}
diff --git a/pesto.h b/pesto.h
new file mode 100644
index 00000000..92d4df3a
--- /dev/null
+++ b/pesto.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright Red Hat
+ * Author: David Gibson
+ *
+ * Definitions and functions used by both client and server of the configuration
+ * update protocol (pesto).
+ */
+
+#ifndef PESTO_H
+#define PESTO_H
+
+#include
+#include
+
+#define PESTO_SERVER_MAGIC "pesto:s"
+
+/* Version 0 is reserved for unreleased / unsupported experimental versions */
+#define PESTO_PROTOCOL_VERSION 0
+
+/**
+ * struct pesto_hello - Server introduction message
+ * @magic: PESTO_SERVER_MAGIC
+ * @version: Version number
+ */
+struct pesto_hello {
+ char magic[8];
+ uint32_t version;
+} __attribute__ ((__packed__));
+
+static_assert(sizeof(PESTO_SERVER_MAGIC)
+ == sizeof(((struct pesto_hello *)0)->magic),
+ "PESTO_SERVER_MAGIC has wrong size");
+
+#endif /* PESTO_H */
diff --git a/serialise.c b/serialise.c
index d6c3396a..e3ea86e3 100644
--- a/serialise.c
+++ b/serialise.c
@@ -6,6 +6,9 @@
* PASTA - Pack A Subtle Tap Abstraction
* for network namespace/tap device mode
*
+ * PESTO - Programmable Extensible Socket Translation Orchestrator
+ * front-end for passt(1) and pasta(1) forwarding configuration
+ *
* serialise.c - Serialisation of data structures over bytestreams
*
* Copyright Red Hat
diff --git a/util.h b/util.h
index cb669105..e7993f4d 100644
--- a/util.h
+++ b/util.h
@@ -317,9 +317,6 @@ static inline bool mod_between(unsigned x, unsigned i, unsigned j, unsigned m)
return mod_sub(x, i, m) < mod_sub(j, i, m);
}
-/* FPRINTF() intentionally silences cert-err33-c clang-tidy warnings */
-#define FPRINTF(f, ...) (void)fprintf(f, __VA_ARGS__)
-
void raw_random(void *buf, size_t buflen);
/*
--
2.53.0