From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: passt.top; dkim=pass (2048-bit key; secure) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202412 header.b=gRphrP13; dkim-atps=neutral Received: from mail.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by passt.top (Postfix) with ESMTPS id 8DE805A0274 for ; Wed, 29 Jan 2025 07:15:51 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202412; t=1738131337; bh=ag46uAn+o7qJho0SJ13pMSi1wSNJYayvlcHXfnx4HTk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gRphrP13+d/UJCCvC9/HsyVG775NeqIGX/NvWfz7zKCBHlVF+qTJ4+Mc8WFU2d2as WxGygEwdEfamAvjTkeN0OlKnwsLc+JjoZ2yGynJYIuJU+4ryXpwgyeYHQSh+1G2hch XNxN1zReAuvkShehzNxe7kzDz0QRauVG9v4GQ9Rdopuem+rrTiEcxb2PZZEforFIw0 s9Blx/bN8Tyfgnx+opSlgzBgNVVIzvKHrmhykihOVMsjA1lOfwYYMLfh+17MeS1p0V RAGWs8eqfqRz+uzqrxGWBBJLX8gf7fFsZ1l+hdCb87irja5Osn4MuFXtbeR8vz8nuq zdxrmh1G92j+w== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4YjX2d4BXKz4wc4; Wed, 29 Jan 2025 17:15:37 +1100 (AEDT) Date: Wed, 29 Jan 2025 17:09:07 +1100 From: David Gibson To: Stefano Brivio Subject: Re: [PATCH v2 7/8] Add interfaces and configuration bits for passt-repair Message-ID: References: <20250128233940.1235855-1-sbrivio@redhat.com> <20250128233940.1235855-8-sbrivio@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="ea/0T7Rq3l4Fl3PT" Content-Disposition: inline In-Reply-To: <20250128233940.1235855-8-sbrivio@redhat.com> Message-ID-Hash: VQP7V7D4V7FJKQEL2GK3ZLECUOWDAOCB X-Message-ID-Hash: VQP7V7D4V7FJKQEL2GK3ZLECUOWDAOCB X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: passt-dev@passt.top, Laurent Vivier X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: --ea/0T7Rq3l4Fl3PT Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jan 29, 2025 at 12:39:39AM +0100, Stefano Brivio wrote: > In vhost-user mode, by default, create a second UNIX domain socket > accepting connections from passt-repair, with the usual listener > socket. >=20 > When we need to set or clear TCP_REPAIR on sockets, we'll send them > via SCM_RIGHTS to passt-repair, who sets the socket option values we > ask for. >=20 > To that end, introduce batched functions to request TCP_REPAIR > settings on sockets, so that we don't have to send a single message > for each socket, on migration. When needed, repair_flush() will > send the message and check for the reply. >=20 > Signed-off-by: Stefano Brivio > --- > Makefile | 12 ++-- > conf.c | 46 ++++++++++-- > epoll_type.h | 4 ++ > passt.1 | 11 +++ > passt.c | 9 +++ > passt.h | 7 ++ > repair.c | 192 +++++++++++++++++++++++++++++++++++++++++++++++++++ > repair.h | 16 +++++ > tap.c | 65 +---------------- > util.c | 62 +++++++++++++++++ > util.h | 1 + > 11 files changed, 353 insertions(+), 72 deletions(-) > create mode 100644 repair.c > create mode 100644 repair.h >=20 > diff --git a/Makefile b/Makefile > index 1b71cb0..f67a20b 100644 > --- a/Makefile > +++ b/Makefile > @@ -38,9 +38,9 @@ FLAGS +=3D -DDUAL_STACK_SOCKETS=3D$(DUAL_STACK_SOCKETS) > =20 > PASST_SRCS =3D arch.c arp.c checksum.c conf.c dhcp.c dhcpv6.c flow.c fwd= =2Ec \ > icmp.c igmp.c inany.c iov.c ip.c isolation.c lineread.c log.c mld.c \ > - ndp.c netlink.c migrate.c packet.c passt.c pasta.c pcap.c pif.c tap.c \ > - tcp.c tcp_buf.c tcp_splice.c tcp_vu.c udp.c udp_flow.c udp_vu.c util.c \ > - vhost_user.c virtio.c vu_common.c > + ndp.c netlink.c migrate.c packet.c passt.c pasta.c pcap.c pif.c \ > + repair.c tap.c tcp.c tcp_buf.c tcp_splice.c tcp_vu.c udp.c udp_flow.c \ > + udp_vu.c util.c vhost_user.c virtio.c vu_common.c > QRAP_SRCS =3D qrap.c > PASST_REPAIR_SRCS =3D passt-repair.c > SRCS =3D $(PASST_SRCS) $(QRAP_SRCS) $(PASST_REPAIR_SRCS) > @@ -50,9 +50,9 @@ MANPAGES =3D passt.1 pasta.1 qrap.1 > PASST_HEADERS =3D arch.h arp.h checksum.h conf.h dhcp.h dhcpv6.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 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 > + 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 > HEADERS =3D $(PASST_HEADERS) seccomp.h > =20 > C :=3D \#include \nint main(){int a=3Dgetrandom(0, 0, 0);} > diff --git a/conf.c b/conf.c > index df2b016..85dec44 100644 > --- a/conf.c > +++ b/conf.c > @@ -816,6 +816,9 @@ static void usage(const char *name, FILE *f, int stat= us) > " UNIX domain socket is provided by -s option\n" > " --print-capabilities print back-end capabilities in JSON format,\n" > " only meaningful for vhost-user mode\n"); > + FPRINTF(f, > + " --repair-path PATH path for passt-repair(1)\n" Nit: as a privileged helper, should it be passt-repair(8)? > + " default: append '.repair' to UNIX domain path\n"); > } > =20 > FPRINTF(f, > @@ -1240,8 +1243,30 @@ static void conf_nat(const char *arg, struct in_ad= dr *addr4, > */ > static void conf_open_files(struct ctx *c) > { > - if (c->mode !=3D MODE_PASTA && c->fd_tap =3D=3D -1) > - c->fd_tap_listen =3D tap_sock_unix_open(c->sock_path); > + if (c->mode !=3D MODE_PASTA && c->fd_tap =3D=3D -1) { > + c->fd_tap_listen =3D sock_unix(c->sock_path); > + > + if (c->mode =3D=3D MODE_VU && strcmp(c->repair_path, "none")) { > + if (!strncmp(c->repair_path, "./", 2)) { > + memmove(c->repair_path, c->repair_path + 2, > + sizeof(c->repair_path) - 2); > + } Do you need this? Shouldn't "./whatever" be usable as-is? > + > + if (!*c->repair_path && > + snprintf_check(c->repair_path, > + sizeof(c->repair_path), "%s.repair", > + c->sock_path)) { > + warn("passt-repair path %s not usable", > + c->repair_path); I'd prefer a die() here - I think omitting a possibly expected feature, with just a warning that could easily be lost in the logs is not a good idea. > + c->fd_repair_listen =3D -1; > + } else { > + c->fd_repair_listen =3D sock_unix(c->repair_path); > + } > + } else { > + c->fd_repair_listen =3D -1; > + } > + c->fd_repair =3D -1; > + } > =20 > if (*c->pidfile) { > c->pidfile_fd =3D output_file_open(c->pidfile, O_WRONLY); > @@ -1354,9 +1379,12 @@ void conf(struct ctx *c, int argc, char **argv) > {"host-lo-to-ns-lo", no_argument, NULL, 23 }, > {"dns-host", required_argument, NULL, 24 }, > {"vhost-user", no_argument, NULL, 25 }, > + > /* vhost-user backend program convention */ > {"print-capabilities", no_argument, NULL, 26 }, > {"socket-path", required_argument, NULL, 's' }, > + > + {"repair-path", required_argument, NULL, 27 }, > { 0 }, > }; > const char *logname =3D (c->mode =3D=3D MODE_PASTA) ? "pasta" : "passt"; > @@ -1824,8 +1852,8 @@ void conf(struct ctx *c, int argc, char **argv) > if (c->ifi4 && IN4_IS_ADDR_UNSPECIFIED(&c->ip4.guest_gw)) > c->no_dhcp =3D 1; > =20 > - /* Inbound port options & DNS can be parsed now (after IPv4/IPv6 > - * settings) > + /* Inbound port options, DNS, and --repair-path can be parsed now, after > + * IPv4/IPv6 settings and --vhost-user. > */ > fwd_probe_ephemeral(); > udp_portmap_clear(); > @@ -1871,6 +1899,16 @@ void conf(struct ctx *c, int argc, char **argv) > } > =20 > die("Cannot use DNS address %s", optarg); > + } else if (name =3D=3D 27) { > + if (c->mode !=3D MODE_VU && strcmp(optarg, "none")) > + die("--repair-path is for vhost-user mode only"); > + > + if (snprintf_check(c->repair_path, > + sizeof(c->repair_path), "%s", > + optarg)) > + die("Invalid passt-repair path: %s", optarg); > + > + break; > } > } while (name !=3D -1); > =20 > diff --git a/epoll_type.h b/epoll_type.h > index fd9eac3..706238a 100644 > --- a/epoll_type.h > +++ b/epoll_type.h > @@ -42,6 +42,10 @@ enum epoll_type { > EPOLL_TYPE_VHOST_KICK, > /* vhost-user migration socket */ > EPOLL_TYPE_VHOST_MIGRATION, > + /* TCP_REPAIR helper listening socket */ > + EPOLL_TYPE_REPAIR_LISTEN, > + /* TCP_REPAIR helper socket */ > + EPOLL_TYPE_REPAIR, > =20 > EPOLL_NUM_TYPES, > }; > diff --git a/passt.1 b/passt.1 > index d9cd33e..63a3a01 100644 > --- a/passt.1 > +++ b/passt.1 > @@ -418,6 +418,17 @@ Enable vhost-user. The vhost-user command socket is = provided by \fB--socket\fR. > .BR \-\-print-capabilities > Print back-end capabilities in JSON format, only meaningful for vhost-us= er mode. > =20 > +.TP > +.BR \-\-repair-path " " \fIpath > +Path for UNIX domain socket used by the \fBpasst-repair\fR(1) helper to = connect passt-repair(8)? > +to \fBpasst\fR in order to set or clear the TCP_REPAIR option on sockets= , during > +migration. \fB--repair-path none\fR disables this interface (if you need= to > +specify a socket path called "none" you can prefix the path by \fI./\fR). > + > +Default, for \-\-vhost-user mode only, is to append \fI.repair\fR to the= path > +chosen for the hypervisor UNIX domain socket. No socket is created if no= t in > +\-\-vhost-user mode. > + > .TP > .BR \-F ", " \-\-fd " " \fIFD > Pass a pre-opened, connected socket to \fBpasst\fR. Usually the socket i= s opened > diff --git a/passt.c b/passt.c > index 184d4e5..1fa2ddd 100644 > --- a/passt.c > +++ b/passt.c > @@ -51,6 +51,7 @@ > #include "tcp_splice.h" > #include "ndp.h" > #include "vu_common.h" > +#include "repair.h" > =20 > #define EPOLL_EVENTS 8 > =20 > @@ -76,6 +77,8 @@ char *epoll_type_str[] =3D { > [EPOLL_TYPE_VHOST_CMD] =3D "vhost-user command socket", > [EPOLL_TYPE_VHOST_KICK] =3D "vhost-user kick socket", > [EPOLL_TYPE_VHOST_MIGRATION] =3D "vhost-user migration socket", > + [EPOLL_TYPE_REPAIR_LISTEN] =3D "TCP_REPAIR helper listening socket", > + [EPOLL_TYPE_REPAIR] =3D "TCP_REPAIR helper socket", > }; > static_assert(ARRAY_SIZE(epoll_type_str) =3D=3D EPOLL_NUM_TYPES, > "epoll_type_str[] doesn't match enum epoll_type"); > @@ -360,6 +363,12 @@ loop: > case EPOLL_TYPE_VHOST_MIGRATION: > vu_migrate(&c, eventmask); > break; > + case EPOLL_TYPE_REPAIR_LISTEN: > + repair_listen_handler(&c, eventmask); > + break; > + case EPOLL_TYPE_REPAIR: > + repair_handler(&c, eventmask); > + break; > default: > /* Can't happen */ > ASSERT(0); > diff --git a/passt.h b/passt.h > index 0dd4efa..85b0a10 100644 > --- a/passt.h > +++ b/passt.h > @@ -20,6 +20,7 @@ union epoll_ref; > #include "siphash.h" > #include "ip.h" > #include "inany.h" > +#include "migrate.h" > #include "flow.h" > #include "icmp.h" > #include "fwd.h" > @@ -193,6 +194,7 @@ 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 > + * @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 > * @pidfile_fd: File descriptor for PID file, -1 if none > @@ -203,6 +205,8 @@ 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_repair_listen: File descriptor for listening TCP_REPAIR socket, i= f any > + * @fd_repair: Connected AF_UNIX socket for TCP_REPAIR helper > * @our_tap_mac: Pasta/passt's MAC on the tap link > * @guest_mac: MAC address of guest or namespace, seen or configured > * @hash_secret: 128-bit secret for siphash functions > @@ -244,6 +248,7 @@ struct ctx { > int foreground; > int nofile; > char sock_path[UNIX_PATH_MAX]; > + char repair_path[UNIX_PATH_MAX]; > char pcap[PATH_MAX]; > =20 > char pidfile[PATH_MAX]; > @@ -260,6 +265,8 @@ struct ctx { > int epollfd; > int fd_tap_listen; > int fd_tap; > + int fd_repair_listen; > + int fd_repair; > unsigned char our_tap_mac[ETH_ALEN]; > unsigned char guest_mac[ETH_ALEN]; > uint64_t hash_secret[2]; > diff --git a/repair.c b/repair.c > new file mode 100644 > index 0000000..24966f5 > --- /dev/null > +++ b/repair.c > @@ -0,0 +1,192 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > + > +/* PASST - Plug A Simple Socket Transport > + * for qemu/UNIX domain socket mode > + * > + * PASTA - Pack A Subtle Tap Abstraction > + * for network namespace/tap device mode > + * > + * repair.c - Interface (server) for passt-repair, set/clear TCP_REPAIR > + * > + * Copyright (c) 2025 Red Hat GmbH > + * Author: Stefano Brivio > + */ > + > +#include > +#include > + > +#include "util.h" > +#include "ip.h" > +#include "passt.h" > +#include "inany.h" > +#include "flow.h" > +#include "flow_table.h" > + > +#include "repair.h" > + > +#define SCM_MAX_FD 253 /* From Linux kernel (include/net/scm.h), not in = UAPI */ > + > +static int fds[SCM_MAX_FD]; Even 'static', I'd prefer a longer name for a global variable. > +static int current_cmd; Is there any particular rationale behind these being globals, whereas fd_repair is in struct ctx? AFAICT they're basically equally global in practice. > +static int nfds; > + > +/** > + * repair_sock_init() - Start listening for connections on helper socket > + * @c: Execution context > + */ > +void repair_sock_init(const struct ctx *c) > +{ > + union epoll_ref ref =3D { .type =3D EPOLL_TYPE_REPAIR_LISTEN }; > + struct epoll_event ev =3D { 0 }; > + > + listen(c->fd_repair_listen, 0); > + > + ref.fd =3D c->fd_repair_listen; > + ev.events =3D EPOLLIN | EPOLLHUP | EPOLLET; > + ev.data.u64 =3D ref.u64; > + epoll_ctl(c->epollfd, EPOLL_CTL_ADD, c->fd_repair_listen, &ev); > +} > + > +/** > + * repair_listen_handler() - Handle events on TCP_REPAIR helper listenin= g socket > + * @c: Execution context > + * @events: epoll events > + */ > +void repair_listen_handler(struct ctx *c, uint32_t events) > +{ > + union epoll_ref ref =3D { .type =3D EPOLL_TYPE_REPAIR }; > + struct epoll_event ev =3D { 0 }; > + struct ucred ucred; > + socklen_t len; > + > + if (events !=3D EPOLLIN) { > + debug("Spurious event 0x%04x on TCP_REPAIR helper socket", > + events); > + return; > + } > + > + len =3D sizeof(ucred); > + > + /* Another client is already connected: accept and close right away. */ For the repair socket, last-connection-wins would make more sense to me than first-connection-wins. While hacking/debugging seems it might be useful to fix something in the passt-repair, re-run it and have it displace the stale version for existing passt instances. > + if (c->fd_repair !=3D -1) { > + int discard =3D accept4(c->fd_repair_listen, NULL, NULL, > + SOCK_NONBLOCK); > + > + if (discard =3D=3D -1) > + return; > + > + if (!getsockopt(discard, SOL_SOCKET, SO_PEERCRED, &ucred, &len)) > + info("Discarding TCP_REPAIR helper, PID %i", ucred.pid); > + > + close(discard); > + return; > + } > + > + c->fd_repair =3D accept4(c->fd_repair_listen, NULL, NULL, 0); > + > + if (!getsockopt(c->fd_repair, SOL_SOCKET, SO_PEERCRED, &ucred, &len)) > + info("Accepted TCP_REPAIR helper, PID %i", ucred.pid); > + > + ref.fd =3D c->fd_repair; > + ev.events =3D EPOLLHUP | EPOLLET; > + ev.data.u64 =3D ref.u64; > + epoll_ctl(c->epollfd, EPOLL_CTL_ADD, c->fd_repair, &ev); > +} > + > +/** > + * repair_close() - Close connection to TCP_REPAIR helper > + * @c: Execution context > + */ > +void repair_close(struct ctx *c) > +{ > + debug("Closing TCP_REPAIR helper socket"); > + > + epoll_ctl(c->epollfd, EPOLL_CTL_DEL, c->fd_repair, NULL); > + close(c->fd_repair); > + c->fd_repair =3D -1; > +} > + > +/** > + * repair_handler() - Handle EPOLLHUP and EPOLLERR on TCP_REPAIR helper = socket > + * @c: Execution context > + * @events: epoll events > + */ > +void repair_handler(struct ctx *c, uint32_t events) > +{ > + (void)events; > + > + repair_close(c); > +} > + > +/** > + * repair_flush() - Flush current set of sockets to helper, with current= command > + * @c: Execution context > + * > + * Return: 0 on success, negative error code on failure > + */ > +int repair_flush(struct ctx *c) > +{ > + struct iovec iov =3D { &((int8_t){ current_cmd }), sizeof(int8_t) }; > + char buf[CMSG_SPACE(sizeof(int) * SCM_MAX_FD)] > + __attribute__ ((aligned(__alignof__(struct cmsghdr)))); > + struct cmsghdr *cmsg; > + struct msghdr msg; > + int ret =3D 0; > + > + if (!nfds) > + return 0; > + > + msg =3D (struct msghdr){ NULL, 0, &iov, 1, > + buf, CMSG_SPACE(sizeof(int) * nfds), 0 }; > + cmsg =3D CMSG_FIRSTHDR(&msg); > + > + cmsg->cmsg_level =3D SOL_SOCKET; > + cmsg->cmsg_type =3D SCM_RIGHTS; > + cmsg->cmsg_len =3D CMSG_LEN(sizeof(int) * nfds); > + memcpy(CMSG_DATA(cmsg), fds, sizeof(int) * nfds); > + > + nfds =3D 0; > + > + if (sendmsg(c->fd_repair, &msg, 0) < 0) { > + ret =3D -errno; This error code won't be reported to the caller: you'll continue on to the recv() below, which will return EBADF, clobbering ret. > + err_perror("Failed to send sockets to TCP_REPAIR helper"); > + repair_close(c); > + } > + > + if (recv(c->fd_repair, &((int8_t){ 0 }), 1, 0) < 0) { > + ret =3D -errno; > + err_perror("Failed to receive reply from TCP_REPAIR helper"); > + repair_close(c); > + } > + > + return ret; > +} > + > +/** > + * repair_flush() - Add socket to TCP_REPAIR set with given command > + * @c: Execution context > + * @s: Socket to add > + * @cmd: TCP_REPAIR_ON, TCP_REPAIR_OFF, or TCP_REPAIR_OFF_NO_WP > + * > + * Return: 0 on success, negative error code on failure > + */ > +/* cppcheck-suppress unusedFunction */ > +int repair_set(struct ctx *c, int s, int cmd) > +{ > + int rc; > + > + if (nfds && current_cmd !=3D cmd) { > + if ((rc =3D repair_flush(c))) > + return rc; > + } > + > + current_cmd =3D cmd; > + fds[nfds++] =3D s; > + > + if (nfds >=3D SCM_MAX_FD) { > + if ((rc =3D repair_flush(c))) > + return rc; > + } > + > + return 0; > +} > diff --git a/repair.h b/repair.h > new file mode 100644 > index 0000000..693c515 > --- /dev/null > +++ b/repair.h > @@ -0,0 +1,16 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later > + * Copyright (c) 2025 Red Hat GmbH > + * Author: Stefano Brivio > + */ > +=20 > +#ifndef REPAIR_H > +#define REPAIR_H > + > +void repair_sock_init(const struct ctx *c); > +void repair_listen_handler(struct ctx *c, uint32_t events); > +void repair_handler(struct ctx *c, uint32_t events); > +void repair_close(struct ctx *c); > +int repair_flush(struct ctx *c); > +int repair_set(struct ctx *c, int s, int cmd); > + > +#endif /* REPAIR_H */ > diff --git a/tap.c b/tap.c > index cd32a90..0e60eb4 100644 > --- a/tap.c > +++ b/tap.c > @@ -56,6 +56,7 @@ > #include "netlink.h" > #include "pasta.h" > #include "packet.h" > +#include "repair.h" > #include "tap.h" > #include "log.h" > #include "vhost_user.h" > @@ -1151,68 +1152,6 @@ void tap_handler_pasta(struct ctx *c, uint32_t eve= nts, > tap_pasta_input(c, now); > } > =20 > -/** > - * tap_sock_unix_open() - Create and bind AF_UNIX socket > - * @sock_path: Socket path. If empty, set on return (UNIX_SOCK_PATH as p= refix) > - * > - * Return: socket descriptor on success, won't return on failure > - */ > -int tap_sock_unix_open(char *sock_path) > -{ > - int fd =3D socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0); > - struct sockaddr_un addr =3D { > - .sun_family =3D AF_UNIX, > - }; > - int i; > - > - if (fd < 0) > - die_perror("Failed to open UNIX domain socket"); > - > - for (i =3D 1; i < UNIX_SOCK_MAX; i++) { > - char *path =3D addr.sun_path; > - int ex, ret; > - > - if (*sock_path) > - memcpy(path, sock_path, UNIX_PATH_MAX); > - else if (snprintf_check(path, UNIX_PATH_MAX - 1, > - UNIX_SOCK_PATH, i)) > - die_perror("Can't build UNIX domain socket path"); > - > - ex =3D socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, > - 0); > - if (ex < 0) > - die_perror("Failed to check for UNIX domain conflicts"); > - > - ret =3D connect(ex, (const struct sockaddr *)&addr, sizeof(addr)); > - if (!ret || (errno !=3D ENOENT && errno !=3D ECONNREFUSED && > - errno !=3D EACCES)) { > - if (*sock_path) > - die("Socket path %s already in use", path); > - > - close(ex); > - continue; > - } > - close(ex); > - > - unlink(path); > - ret =3D bind(fd, (const struct sockaddr *)&addr, sizeof(addr)); > - if (*sock_path && ret) > - die_perror("Failed to bind UNIX domain socket"); > - > - if (!ret) > - break; > - } > - > - if (i =3D=3D UNIX_SOCK_MAX) > - die_perror("Failed to bind UNIX domain socket"); > - > - info("UNIX domain socket bound at %s", addr.sun_path); > - if (!*sock_path) > - memcpy(sock_path, addr.sun_path, UNIX_PATH_MAX); > - > - return fd; > -} > - > /** > * tap_backend_show_hints() - Give help information to start QEMU > * @c: Execution context > @@ -1423,6 +1362,8 @@ void tap_backend_init(struct ctx *c) > tap_sock_tun_init(c); > break; > case MODE_VU: > + repair_sock_init(c); > + /* fall through */ > case MODE_PASST: > tap_sock_unix_init(c); > =20 > diff --git a/util.c b/util.c > index 36857d4..e98da74 100644 > --- a/util.c > +++ b/util.c > @@ -178,6 +178,68 @@ int sock_l4_sa(const struct ctx *c, enum epoll_type = type, > return fd; > } > =20 > +/** > + * sock_unix() - Create and bind AF_UNIX socket > + * @sock_path: Socket path. If empty, set on return (UNIX_SOCK_PATH as p= refix) > + * > + * Return: socket descriptor on success, won't return on failure > + */ I like making tap_sock_unix_open() more general. Could be split into a separate patch. > +int sock_unix(char *sock_path) > +{ > + int fd =3D socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0); > + struct sockaddr_un addr =3D { > + .sun_family =3D AF_UNIX, > + }; > + int i; > + > + if (fd < 0) > + die_perror("Failed to open UNIX domain socket"); > + > + for (i =3D 1; i < UNIX_SOCK_MAX; i++) { > + char *path =3D addr.sun_path; > + int ex, ret; > + > + if (*sock_path) > + memcpy(path, sock_path, UNIX_PATH_MAX); > + else if (snprintf_check(path, UNIX_PATH_MAX - 1, > + UNIX_SOCK_PATH, i)) > + die_perror("Can't build UNIX domain socket path"); > + > + ex =3D socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK | SOCK_CLOEXEC, > + 0); > + if (ex < 0) > + die_perror("Failed to check for UNIX domain conflicts"); > + > + ret =3D connect(ex, (const struct sockaddr *)&addr, sizeof(addr)); > + if (!ret || (errno !=3D ENOENT && errno !=3D ECONNREFUSED && > + errno !=3D EACCES)) { > + if (*sock_path) > + die("Socket path %s already in use", path); > + > + close(ex); > + continue; > + } > + close(ex); > + > + unlink(path); > + ret =3D bind(fd, (const struct sockaddr *)&addr, sizeof(addr)); > + if (*sock_path && ret) > + die_perror("Failed to bind UNIX domain socket"); > + > + if (!ret) > + break; > + } > + > + if (i =3D=3D UNIX_SOCK_MAX) > + die_perror("Failed to bind UNIX domain socket"); > + > + info("UNIX domain socket bound at %s", addr.sun_path); > + if (!*sock_path) > + memcpy(sock_path, addr.sun_path, UNIX_PATH_MAX); > + > + return fd; > +} > + > /** > * sock_probe_mem() - Check if setting high SO_SNDBUF and SO_RCVBUF is a= llowed > * @c: Execution context > diff --git a/util.h b/util.h > index 73a7a33..d2fd2fe 100644 > --- a/util.h > +++ b/util.h > @@ -185,6 +185,7 @@ struct ctx; > int sock_l4_sa(const struct ctx *c, enum epoll_type type, > const void *sa, socklen_t sl, > const char *ifname, bool v6only, uint32_t data); > +int sock_unix(char *sock_path); > void sock_probe_mem(struct ctx *c); > long timespec_diff_ms(const struct timespec *a, const struct timespec *b= ); > int64_t timespec_diff_us(const struct timespec *a, const struct timespec= *b); --=20 David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson --ea/0T7Rq3l4Fl3PT Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEO+dNsU4E3yXUXRK2zQJF27ox2GcFAmeZxgIACgkQzQJF27ox 2GcjQQ//S1G/0w3FOK+wj7u11mNSa3QfBeJn6+73O4shb5zSgi5fj0Cfjia6wLxU o9cEPeYb12WQXzpUSqPmpmOCVWQXT52A7pY8pAR7KvD3LjjE4DMyTQrFR4Xd2IqY cLBwkScdVfPbLQODA1IMLWvsfYn101KZ58tHkTsYEJyOQ22bj+VrHuT6UTUmgxto xP8x2UQpMzGepIsXEjOP9XncgkVl/MTGi3tB9M6l+/uSSy1nDLph+BPesTIC+JjM +hDO9fnG8n7/bSifisvh1PLKjrMbaPwmn4svLLSgFhRDnpC9ekctb5E0/9/G93dS JAdd4VnJBx5sqgvwtwZKpIDNAgYtyJRe4U5LwGMWB+DGou563s8C+zpDpD4qlqJa E6Eb13I3Fz5OnFEaxhglhDNci+xJZ51z1slRXCLG7QaDLqFxKA87bxB4bmcGMv4I 8NgTePKMXct8zw7YHbxkXsgp7hWRIr7s8YkzjA/Sj8NW/YFbQyytWzqOojbmEv08 V9L65XklZGLmCMoe73cNaLFgKAf84Ya3z4x4KpEn/l3bRpVvdCiG/0w+iqlUrXXf SbNqRU5YbEtNx+x34vqyKnbmWhEhIg0xyga0IPg3WdkV2who5WyuvXaEC64pri4D XwleHvw6Mxkf28Ypr4rsPj9dBCfXfR7L/1X2SoMgTEzVDXxocSU= =fFlX -----END PGP SIGNATURE----- --ea/0T7Rq3l4Fl3PT--