Use explicit --netns option rather than multiplexing with PID
When attaching to an existing namespace, pasta can take a PID or the name or path of a network namespace as a non-option parameter. We disambiguate based on what the parameter looks like. Make this more explicit by using a --netns option for explicitly giving the path or name, and treating a non-option argument always as a PID. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> [sbrivio: Fix typo in man page] Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson
Stefano Brivio
parent
9e0dbc8948
commit
c188736cd8
2 changed files with 75 additions and 30 deletions
89
conf.c
89
conf.c
|
|
@ -490,34 +490,16 @@ out:
|
|||
}
|
||||
|
||||
/**
|
||||
* conf_ns_opt() - Parse non-option argument to namespace paths
|
||||
* @userns: buffer of size PATH_MAX, initially contains --userns
|
||||
* argument (may be empty), updated with userns path
|
||||
* conf_netns() - Parse --netns option
|
||||
* @netns: buffer of size PATH_MAX, updated with netns path
|
||||
* @arg: PID, path or name of network namespace
|
||||
* @arg: --netns argument
|
||||
*
|
||||
* Return: 0 on success, negative error code otherwise
|
||||
*/
|
||||
static int conf_ns_opt(char *userns, char *netns, const char *arg)
|
||||
static int conf_netns(char *netns, const char *arg)
|
||||
{
|
||||
char *endptr;
|
||||
long pidval;
|
||||
int ret;
|
||||
|
||||
pidval = strtol(arg, &endptr, 10);
|
||||
if (!*endptr) {
|
||||
/* Looks like a pid */
|
||||
if (pidval < 0 || pidval > INT_MAX) {
|
||||
err("Invalid PID %s", arg);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
snprintf(netns, PATH_MAX, "/proc/%ld/ns/net", pidval);
|
||||
if (!*userns)
|
||||
snprintf(userns, PATH_MAX, "/proc/%ld/ns/user", pidval);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (!strchr(arg, '/')) {
|
||||
/* looks like a netns name */
|
||||
ret = snprintf(netns, PATH_MAX, "%s/%s", NETNS_RUN_DIR, arg);
|
||||
|
|
@ -534,6 +516,43 @@ static int conf_ns_opt(char *userns, char *netns, const char *arg)
|
|||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* conf_ns_pid() - Parse non-option argument as a PID
|
||||
* @userns: buffer of size PATH_MAX, initially contains --userns
|
||||
* argument (may be empty), updated with userns path
|
||||
* @netns: buffer of size PATH_MAX, initial contains --netns
|
||||
* argument (may be empty), updated with netns path
|
||||
* @arg: PID of network namespace
|
||||
*
|
||||
* Return: 0 on success, negative error code otherwise
|
||||
*/
|
||||
static int conf_ns_pid(char *userns, char *netns, const char *arg)
|
||||
{
|
||||
char *endptr;
|
||||
long pidval;
|
||||
|
||||
if (*netns) {
|
||||
err("Both --netns and PID given");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
pidval = strtol(arg, &endptr, 10);
|
||||
if (!*endptr) {
|
||||
/* Looks like a pid */
|
||||
if (pidval < 0 || pidval > INT_MAX) {
|
||||
err("Invalid PID %s", arg);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
snprintf(netns, PATH_MAX, "/proc/%ld/ns/net", pidval);
|
||||
if (!*userns)
|
||||
snprintf(userns, PATH_MAX, "/proc/%ld/ns/user", pidval);
|
||||
return 0;
|
||||
}
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/**
|
||||
* conf_ns_check() - Check if we can enter configured namespaces
|
||||
* @arg: Execution context
|
||||
|
|
@ -708,10 +727,13 @@ static unsigned int conf_ip6(unsigned int ifi,
|
|||
static void usage(const char *name)
|
||||
{
|
||||
if (strstr(name, "pasta")) {
|
||||
info("Usage: %s [OPTION]... [PID|PATH|NAME]", name);
|
||||
info("Usage: %s [OPTION]... [COMMAND] [ARGS]...", name);
|
||||
info(" %s [OPTION]... PID", name);
|
||||
info(" %s [OPTION]... --netns [PATH|NAME]", name);
|
||||
info("");
|
||||
info("Without PID|PATH|NAME, run the default shell in a new");
|
||||
info("network and user namespace, and connect it via pasta.");
|
||||
info("Without PID or --netns, run the given command or a");
|
||||
info("default shell in a new network and user namespace, and");
|
||||
info("connect it via pasta.");
|
||||
} else {
|
||||
info("Usage: %s [OPTION]...", name);
|
||||
}
|
||||
|
|
@ -858,6 +880,7 @@ pasta_opts:
|
|||
info( " SPEC is as described above");
|
||||
info( " default: auto");
|
||||
info( " --userns NSPATH Target user namespace to join");
|
||||
info( " --netns PATH|NAME Target network namespace to join");
|
||||
info( " --netns-only Don't join existing user namespace");
|
||||
info( " implied if PATH or NAME are given without --userns");
|
||||
info( " --config-net Configure tap interface in namespace");
|
||||
|
|
@ -1038,6 +1061,7 @@ void conf(struct ctx *c, int argc, char **argv)
|
|||
{"tcp-ns", required_argument, NULL, 'T' },
|
||||
{"udp-ns", required_argument, NULL, 'U' },
|
||||
{"userns", required_argument, NULL, 2 },
|
||||
{"netns", required_argument, NULL, 3 },
|
||||
{"netns-only", no_argument, &c->netns_only, 1 },
|
||||
{"config-net", no_argument, &c->pasta_conf_ns, 1 },
|
||||
{"ns-mac-addr", required_argument, NULL, 4 },
|
||||
|
|
@ -1091,6 +1115,16 @@ void conf(struct ctx *c, int argc, char **argv)
|
|||
usage(argv[0]);
|
||||
}
|
||||
break;
|
||||
case 3:
|
||||
if (c->mode != MODE_PASTA) {
|
||||
err("--netns is for pasta mode only");
|
||||
usage(argv[0]);
|
||||
}
|
||||
|
||||
ret = conf_netns(netns, optarg);
|
||||
if (ret < 0)
|
||||
usage(argv[0]);
|
||||
break;
|
||||
case 4:
|
||||
if (c->mode != MODE_PASTA) {
|
||||
err("--ns-mac-addr is for pasta mode only");
|
||||
|
|
@ -1465,11 +1499,12 @@ void conf(struct ctx *c, int argc, char **argv)
|
|||
check_root(c);
|
||||
|
||||
if (c->mode == MODE_PASTA && optind + 1 == argc) {
|
||||
ret = conf_ns_opt(userns, netns, argv[optind]);
|
||||
ret = conf_ns_pid(userns, netns, argv[optind]);
|
||||
if (ret < 0)
|
||||
usage(argv[0]);
|
||||
} else if (c->mode == MODE_PASTA && *userns && optind == argc) {
|
||||
err("--userns requires PID, PATH or NAME");
|
||||
} else if (c->mode == MODE_PASTA && *userns
|
||||
&& !*netns && optind == argc) {
|
||||
err("--userns requires --netns or PID");
|
||||
usage(argv[0]);
|
||||
} else if (optind != argc) {
|
||||
usage(argv[0]);
|
||||
|
|
|
|||
16
passt.1
16
passt.1
|
|
@ -15,7 +15,10 @@
|
|||
[\fIOPTION\fR]...
|
||||
.br
|
||||
.B pasta
|
||||
[\fIOPTION\fR]... [\fIPID\fR|\fIPATH\fR|\fINAME\fR]
|
||||
[\fIOPTION\fR]... [\fIPID\fR]
|
||||
.br
|
||||
.B pasta
|
||||
[\fIOPTION\fR]... \fB--netns\fR [\fIPATH\fR|\fINAME\fR]
|
||||
|
||||
.SH DESCRIPTION
|
||||
|
||||
|
|
@ -59,7 +62,7 @@ or with the \fBqrap\fR(1) wrapper.
|
|||
equivalent functionality to network namespaces, as the one offered by
|
||||
\fBpasst\fR for virtual machines.
|
||||
|
||||
If PID, PATH or NAME are given, \fBpasta\fR associates to an existing user and
|
||||
If PID or --netns are given, \fBpasta\fR associates to an existing user and
|
||||
network namespace. Otherwise, \fBpasta\fR creates a new user and network
|
||||
namespace, and spawns an interactive shell within this context. A \fItap\fR
|
||||
device within the network namespace is created to provide network connectivity.
|
||||
|
|
@ -445,7 +448,14 @@ Default is \fBauto\fR.
|
|||
Target user namespace to join, as a path. If PID is given, without this option,
|
||||
the user namespace will be the one of the corresponding process.
|
||||
|
||||
This option requires PID, PATH or NAME to be specified.
|
||||
This option requires --netns or a PID to be specified.
|
||||
|
||||
.TP
|
||||
.BR \-\-netns " " \fIspec
|
||||
Target network namespace to join, as a path or a name. A name is treated as
|
||||
with \fBip-netns(8)\fR as equivalent to a path in \fI/run/netns\fR.
|
||||
|
||||
This option can't be specified with a PID.
|
||||
|
||||
.TP
|
||||
.BR \-\-netns-only
|
||||
|
|
|
|||
Loading…
Reference in a new issue