passt/conf.c
Stefano Brivio 3e2eb4337b conf: Bind inbound ports with CAP_NET_BIND_SERVICE before isolate_user()
Even if CAP_NET_BIND_SERVICE is granted, we'll lose the capability in
the target user namespace as we isolate the process, which means
we're unable to bind to low ports at that point.

Bind inbound ports, and only those, before isolate_user(). Keep the
handling of outbound ports (for pasta mode only) after the setup of
the namespace, because that's where we'll bind them.

To this end, initialise the netlink socket for the init namespace
before isolate_user() as well, as we actually need to know the
addresses of the upstream interface before binding ports, in case
they're not explicitly passed by the user.

As we now call nl_sock_init() twice, checking its return code from
conf() twice looks a bit heavy: make it exit(), instead, as we
can't do much if we don't have netlink sockets.

While at it:

- move the v4_only && v6_only options check just after the first
  option processing loop, as this is more strictly related to
  option parsing proper

- update the man page, explaining that CAP_NET_BIND_SERVICE is
  *not* the preferred way to bind ports, because passt and pasta
  can be abused to allow other processes to make effective usage
  of it. Add a note about the recommended sysctl instead

- simplify nl_sock_init_do() now that it's called once for each
  case

Reported-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00

1667 lines
43 KiB
C

// SPDX-License-Identifier: AGPL-3.0-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
*
* conf.c - Configuration settings and option parsing
*
* Copyright (c) 2020-2021 Red Hat GmbH
* Author: Stefano Brivio <sbrivio@redhat.com>
*/
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <string.h>
#include <sched.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <limits.h>
#include <grp.h>
#include <pwd.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <syslog.h>
#include <time.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include "util.h"
#include "passt.h"
#include "netlink.h"
#include "udp.h"
#include "tcp.h"
#include "pasta.h"
#include "lineread.h"
#include "isolation.h"
#include "log.h"
/**
* get_bound_ports() - Get maps of ports with bound sockets
* @c: Execution context
* @ns: If set, set bitmaps for ports to tap/ns -- to init otherwise
* @proto: Protocol number (IPPROTO_TCP or IPPROTO_UDP)
*/
void get_bound_ports(struct ctx *c, int ns, uint8_t proto)
{
uint8_t *udp_map, *udp_excl, *tcp_map, *tcp_excl;
if (ns) {
udp_map = c->udp.fwd_in.f.map;
udp_excl = c->udp.fwd_out.f.map;
tcp_map = c->tcp.fwd_in.map;
tcp_excl = c->tcp.fwd_out.map;
} else {
udp_map = c->udp.fwd_out.f.map;
udp_excl = c->udp.fwd_in.f.map;
tcp_map = c->tcp.fwd_out.map;
tcp_excl = c->tcp.fwd_in.map;
}
if (proto == IPPROTO_UDP) {
memset(udp_map, 0, PORT_BITMAP_SIZE);
procfs_scan_listen(c, IPPROTO_UDP, V4, ns, udp_map, udp_excl);
procfs_scan_listen(c, IPPROTO_UDP, V6, ns, udp_map, udp_excl);
procfs_scan_listen(c, IPPROTO_TCP, V4, ns, udp_map, udp_excl);
procfs_scan_listen(c, IPPROTO_TCP, V6, ns, udp_map, udp_excl);
} else if (proto == IPPROTO_TCP) {
memset(tcp_map, 0, PORT_BITMAP_SIZE);
procfs_scan_listen(c, IPPROTO_TCP, V4, ns, tcp_map, tcp_excl);
procfs_scan_listen(c, IPPROTO_TCP, V6, ns, tcp_map, tcp_excl);
}
}
/**
* struct get_bound_ports_ns_arg - Arguments for get_bound_ports_ns()
* @c: Execution context
* @proto: Protocol number (IPPROTO_TCP or IPPROTO_UDP)
*/
struct get_bound_ports_ns_arg {
struct ctx *c;
uint8_t proto;
};
/**
* get_bound_ports_ns() - Get maps of ports in namespace with bound sockets
* @arg: See struct get_bound_ports_ns_arg
*
* Return: 0
*/
static int get_bound_ports_ns(void *arg)
{
struct get_bound_ports_ns_arg *a = (struct get_bound_ports_ns_arg *)arg;
struct ctx *c = a->c;
if (!c->pasta_netns_fd || ns_enter(c))
return 0;
get_bound_ports(c, 1, a->proto);
return 0;
}
/**
* next_chunk - Return the next piece of a string delimited by a character
* @s: String to search
* @c: Delimiter character
*
* Returns: If another @c is found in @s, returns a pointer to the
* character *after* the delimiter, if no further @c is in
* @s, return NULL
*/
static char *next_chunk(const char *s, char c)
{
char *sep = strchr(s, c);
return sep ? sep + 1 : NULL;
}
/**
* port_range - Represents a non-empty range of ports
* @first: First port number in the range
* @last: Last port number in the range (inclusive)
*
* Invariant: @last >= @first
*/
struct port_range {
in_port_t first, last;
};
/**
* parse_port_range() - Parse a range of port numbers '<first>[-<last>]'
* @s: String to parse
* @endptr: Update to the character after the parsed range (similar to
* strtol() etc.)
* @range: Update with the parsed values on success
*
* Return: -EINVAL on parsing error, -ERANGE on out of range port
* numbers, 0 on success
*/
static int parse_port_range(const char *s, char **endptr,
struct port_range *range)
{
unsigned long first, last;
last = first = strtoul(s, endptr, 10);
if (*endptr == s) /* Parsed nothing */
return -EINVAL;
if (**endptr == '-') { /* we have a last value too */
const char *lasts = *endptr + 1;
last = strtoul(lasts, endptr, 10);
if (*endptr == lasts) /* Parsed nothing */
return -EINVAL;
}
if ((last < first) || (last >= NUM_PORTS))
return -ERANGE;
range->first = first;
range->last = last;
return 0;
}
/**
* conf_ports() - Parse port configuration options, initialise UDP/TCP sockets
* @c: Execution context
* @optname: Short option name, t, T, u, or U
* @optarg: Option argument (port specification)
* @fwd: Pointer to @port_fwd to be updated
*
* Return: -EINVAL on parsing error, 0 otherwise
*/
static int conf_ports(const struct ctx *c, char optname, const char *optarg,
struct port_fwd *fwd)
{
char addr_buf[sizeof(struct in6_addr)] = { 0 }, *addr = addr_buf;
char buf[BUFSIZ], *spec, *ifname = NULL, *p;
uint8_t exclude[PORT_BITMAP_SIZE] = { 0 };
sa_family_t af = AF_UNSPEC;
bool exclude_only = true;
if (!strcmp(optarg, "none")) {
if (fwd->mode)
return -EINVAL;
fwd->mode = FWD_NONE;
return 0;
}
if (!strcmp(optarg, "auto")) {
if (fwd->mode || c->mode != MODE_PASTA)
return -EINVAL;
fwd->mode = FWD_AUTO;
return 0;
}
if (!strcmp(optarg, "all")) {
unsigned i;
if (fwd->mode || c->mode != MODE_PASST)
return -EINVAL;
fwd->mode = FWD_ALL;
memset(fwd->map, 0xff, PORT_EPHEMERAL_MIN / 8);
for (i = 0; i < PORT_EPHEMERAL_MIN; i++) {
if (optname == 't')
tcp_sock_init(c, 0, AF_UNSPEC, NULL, NULL, i);
else if (optname == 'u')
udp_sock_init(c, 0, AF_UNSPEC, NULL, NULL, i);
}
return 0;
}
if (fwd->mode > FWD_SPEC)
return -EINVAL;
fwd->mode = FWD_SPEC;
strncpy(buf, optarg, sizeof(buf) - 1);
if ((spec = strchr(buf, '/'))) {
*spec = 0;
spec++;
if (optname != 't' && optname != 'u')
goto bad;
if ((ifname = strchr(buf, '%'))) {
if (spec - ifname >= IFNAMSIZ - 1)
goto bad;
*ifname = 0;
ifname++;
}
if (inet_pton(AF_INET, buf, addr))
af = AF_INET;
else if (inet_pton(AF_INET6, buf, addr))
af = AF_INET6;
else
goto bad;
} else {
spec = buf;
addr = NULL;
}
/* Mark all exclusions first, they might be given after base ranges */
p = spec;
do {
struct port_range xrange;
unsigned i;
if (*p != '~') {
/* Not an exclude range, parse later */
exclude_only = false;
continue;
}
if (parse_port_range(p, &p, &xrange))
goto bad;
if ((*p != '\0') && (*p != ',')) /* Garbage after the range */
goto bad;
for (i = xrange.first; i <= xrange.last; i++) {
if (bitmap_isset(exclude, i))
goto overlap;
bitmap_set(exclude, i);
}
} while ((p = next_chunk(p, ',')));
if (exclude_only) {
unsigned i;
for (i = 0; i < PORT_EPHEMERAL_MIN; i++) {
if (bitmap_isset(exclude, i))
continue;
bitmap_set(fwd->map, i);
if (optname == 't')
tcp_sock_init(c, 0, af, addr, ifname, i);
else if (optname == 'u')
udp_sock_init(c, 0, af, addr, ifname, i);
}
return 0;
}
/* Now process base ranges, skipping exclusions */
p = spec;
do {
struct port_range orig_range, mapped_range;
unsigned i;
if (*p == '~')
/* Exclude range, already parsed */
continue;
if (parse_port_range(p, &p, &orig_range))
goto bad;
if (*p == ':') { /* There's a range to map to as well */
if (parse_port_range(p + 1, &p, &mapped_range))
goto bad;
if ((mapped_range.last - mapped_range.first) !=
(orig_range.last - orig_range.first))
goto bad;
} else {
mapped_range = orig_range;
}
if ((*p != '\0') && (*p != ',')) /* Garbage after the ranges */
goto bad;
for (i = orig_range.first; i <= orig_range.last; i++) {
if (bitmap_isset(fwd->map, i))
goto overlap;
if (bitmap_isset(exclude, i))
continue;
bitmap_set(fwd->map, i);
fwd->delta[i] = mapped_range.first - orig_range.first;
if (optname == 't')
tcp_sock_init(c, 0, af, addr, ifname, i);
else if (optname == 'u')
udp_sock_init(c, 0, af, addr, ifname, i);
}
} while ((p = next_chunk(p, ',')));
return 0;
bad:
err("Invalid port specifier %s", optarg);
return -EINVAL;
overlap:
err("Overlapping port specifier %s", optarg);
return -EINVAL;
}
/**
* get_dns() - Get nameserver addresses from local /etc/resolv.conf
* @c: Execution context
*/
static void get_dns(struct ctx *c)
{
int dns4_set, dns6_set, dnss_set, dns_set, fd;
struct in6_addr *dns6 = &c->ip6.dns[0];
struct fqdn *s = c->dns_search;
uint32_t *dns4 = &c->ip4.dns[0];
struct lineread resolvconf;
int line_len;
char *line, *p, *end;
dns4_set = !c->ifi4 || !!*dns4;
dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(dns6);
dnss_set = !!*s->n || c->no_dns_search;
dns_set = (dns4_set && dns6_set) || c->no_dns;
if (dns_set && dnss_set)
return;
if ((fd = open("/etc/resolv.conf", O_RDONLY | O_CLOEXEC)) < 0)
goto out;
lineread_init(&resolvconf, fd);
while ((line_len = lineread_get(&resolvconf, &line)) > 0) {
if (!dns_set && strstr(line, "nameserver ") == line) {
p = strrchr(line, ' ');
if (!p)
continue;
end = strpbrk(line, "%\n");
if (end)
*end = 0;
if (!dns4_set &&
dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) - 1 &&
inet_pton(AF_INET, p + 1, dns4)) {
/* We can only access local addresses via the gw redirect */
if (ntohl(*dns4) >> IN_CLASSA_NSHIFT == IN_LOOPBACKNET) {
if (c->no_map_gw) {
*dns4 = 0;
continue;
}
*dns4 = c->ip4.gw;
}
dns4++;
*dns4 = 0;
}
if (!dns6_set &&
dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) - 1 &&
inet_pton(AF_INET6, p + 1, dns6)) {
/* We can only access local addresses via the gw redirect */
if (IN6_IS_ADDR_LOOPBACK(dns6)) {
if (c->no_map_gw) {
memset(dns6, 0, sizeof(*dns6));
continue;
}
memcpy(dns6, &c->ip6.gw, sizeof(*dns6));
}
dns6++;
memset(dns6, 0, sizeof(*dns6));
}
} else if (!dnss_set && strstr(line, "search ") == line &&
s == c->dns_search) {
end = strpbrk(line, "\n");
if (end)
*end = 0;
/* cppcheck-suppress strtokCalled */
if (!strtok(line, " \t"))
continue;
while (s - c->dns_search < ARRAY_SIZE(c->dns_search) - 1
/* cppcheck-suppress strtokCalled */
&& (p = strtok(NULL, " \t"))) {
strncpy(s->n, p, sizeof(c->dns_search[0]));
s++;
*s->n = 0;
}
}
}
if (line_len < 0)
warn("Error reading /etc/resolv.conf: %s", strerror(errno));
close(fd);
out:
if (!dns_set && dns4 == c->ip4.dns && dns6 == c->ip6.dns)
warn("Couldn't get any nameserver address");
}
/**
* conf_netns_opt() - Parse --netns option
* @netns: buffer of size PATH_MAX, updated with netns path
* @arg: --netns argument
*
* Return: 0 on success, negative error code otherwise
*/
static int conf_netns_opt(char *netns, const char *arg)
{
int ret;
if (!strchr(arg, '/')) {
/* looks like a netns name */
ret = snprintf(netns, PATH_MAX, "%s/%s", NETNS_RUN_DIR, arg);
} else {
/* otherwise assume it's a netns path */
ret = snprintf(netns, PATH_MAX, "%s", arg);
}
if (ret <= 0 || ret > PATH_MAX) {
err("Network namespace name/path %s too long");
return -E2BIG;
}
return 0;
}
/**
* conf_pasta_ns() - Validate all pasta namespace options
* @netns_only: Don't use userns, may be updated
* @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
* @optind: Index of first non-option argument
* @argc: Number of arguments
* @argv: Command line arguments
*
* Return: 0 on success, negative error code otherwise
*/
static int conf_pasta_ns(int *netns_only, char *userns, char *netns,
int optind, int argc, char *argv[])
{
if (*netns_only && *userns) {
err("Both --userns and --netns-only given");
return -EINVAL;
}
if (*netns && optind != argc) {
err("Both --netns and PID or command given");
return -EINVAL;
}
if (optind + 1 == argc) {
char *endptr;
long pidval;
pidval = strtol(argv[optind], &endptr, 10);
if (!*endptr) {
/* Looks like a pid */
if (pidval < 0 || pidval > INT_MAX) {
err("Invalid PID %s", argv[optind]);
return -EINVAL;
}
snprintf(netns, PATH_MAX, "/proc/%ld/ns/net", pidval);
if (!*userns)
snprintf(userns, PATH_MAX, "/proc/%ld/ns/user",
pidval);
}
}
/* Attaching to a netns/PID, with no userns given */
if (*netns && !*userns)
*netns_only = 1;
return 0;
}
/**
* conf_ip4() - Verify or detect IPv4 support, get relevant addresses
* @ifi: Host interface to attempt (0 to determine one)
* @ip4: IPv4 context (will be written)
* @mac: MAC address to use (written if unset)
*
* Return: Interface index for IPv4, or 0 on failure.
*/
static unsigned int conf_ip4(unsigned int ifi,
struct ip4_ctx *ip4, unsigned char *mac)
{
if (!ifi)
ifi = nl_get_ext_if(AF_INET);
if (!ifi) {
warn("No external routable interface for IPv4");
return 0;
}
if (!ip4->gw)
nl_route(0, ifi, AF_INET, &ip4->gw);
if (!ip4->addr) {
int mask_len = 0;
nl_addr(0, ifi, AF_INET, &ip4->addr, &mask_len, NULL);
ip4->mask = htonl(0xffffffff << (32 - mask_len));
}
if (!ip4->mask) {
if (IN_CLASSA(ntohl(ip4->addr)))
ip4->mask = htonl(IN_CLASSA_NET);
else if (IN_CLASSB(ntohl(ip4->addr)))
ip4->mask = htonl(IN_CLASSB_NET);
else if (IN_CLASSC(ntohl(ip4->addr)))
ip4->mask = htonl(IN_CLASSC_NET);
else
ip4->mask = 0xffffffff;
}
memcpy(&ip4->addr_seen, &ip4->addr, sizeof(ip4->addr_seen));
if (MAC_IS_ZERO(mac))
nl_link(0, ifi, mac, 0, 0);
if (!ip4->gw || !ip4->addr || MAC_IS_ZERO(mac))
return 0;
return ifi;
}
/**
* conf_ip6() - Verify or detect IPv6 support, get relevant addresses
* @ifi: Host interface to attempt (0 to determine one)
* @ip6: IPv6 context (will be written)
* @mac: MAC address to use (written if unset)
*
* Return: Interface index for IPv6, or 0 on failure.
*/
static unsigned int conf_ip6(unsigned int ifi,
struct ip6_ctx *ip6, unsigned char *mac)
{
int prefix_len = 0;
if (!ifi)
ifi = nl_get_ext_if(AF_INET6);
if (!ifi) {
warn("No external routable interface for IPv6");
return 0;
}
if (IN6_IS_ADDR_UNSPECIFIED(&ip6->gw))
nl_route(0, ifi, AF_INET6, &ip6->gw);
nl_addr(0, ifi, AF_INET6,
IN6_IS_ADDR_UNSPECIFIED(&ip6->addr) ? &ip6->addr : NULL,
&prefix_len, &ip6->addr_ll);
memcpy(&ip6->addr_seen, &ip6->addr, sizeof(ip6->addr));
memcpy(&ip6->addr_ll_seen, &ip6->addr_ll, sizeof(ip6->addr_ll));
if (MAC_IS_ZERO(mac))
nl_link(0, ifi, mac, 0, 0);
if (IN6_IS_ADDR_UNSPECIFIED(&ip6->gw) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->addr) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->addr_ll) ||
MAC_IS_ZERO(mac))
return 0;
return ifi;
}
/**
* usage() - Print usage and exit
* @name: Executable name
*/
static void usage(const char *name)
{
if (strstr(name, "pasta")) {
info("Usage: %s [OPTION]... [COMMAND] [ARGS]...", name);
info(" %s [OPTION]... PID", name);
info(" %s [OPTION]... --netns [PATH|NAME]", name);
info("");
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);
}
info("");
info( " -d, --debug Be verbose, don't run in background");
info( " --trace Be extra verbose, implies --debug");
info( " -q, --quiet Don't print informational messages");
info( " -f, --foreground Don't run in background");
info( " default: run in background if started from a TTY");
info( " -e, --stderr Log to stderr too");
info( " default: log to system logger only if started from a TTY");
info( " -l, --log-file PATH Log (only) to given file");
info( " --log-size BYTES Maximum size of log file");
info( " default: 1 MiB");
info( " --runas UID|UID:GID Run as given UID, GID, which can be");
info( " numeric, or login and group names");
info( " default: drop to user \"nobody\"");
info( " -h, --help Display this help message and exit");
info( " --version Show version and exit");
if (strstr(name, "pasta")) {
info( " -I, --ns-ifname NAME namespace interface name");
info( " default: same interface name as external one");
} else {
info( " -s, --socket PATH UNIX domain socket path");
info( " default: probe free path starting from "
UNIX_SOCK_PATH, 1);
}
info( " -p, --pcap FILE Log tap-facing traffic to pcap file");
info( " -P, --pid FILE Write own PID to the given file");
info( " -m, --mtu MTU Assign MTU via DHCP/NDP");
info( " a zero value disables assignment");
info( " default: 65520: maximum 802.3 MTU minus 802.3 header");
info( " length, rounded to 32 bits (IPv4 words)");
info( " -a, --address ADDR Assign IPv4 or IPv6 address ADDR");
info( " can be specified zero to two times (for IPv4 and IPv6)");
info( " default: use addresses from interface with default route");
info( " -n, --netmask MASK Assign IPv4 MASK, dot-decimal or bits");
info( " default: netmask from matching address on the host");
info( " -M, --mac-addr ADDR Use source MAC address ADDR");
info( " default: MAC address from interface with default route");
info( " -g, --gateway ADDR Pass IPv4 or IPv6 address as gateway");
info( " default: gateway from interface with default route");
info( " -i, --interface NAME Interface for addresses and routes");
info( " default: interface with first default route");
info( " -D, --dns ADDR Use IPv4 or IPv6 address as DNS");
info( " can be specified multiple times");
info( " a single, empty option disables DNS information");
if (strstr(name, "pasta"))
info( " default: don't use any addresses");
else
info( " default: use addresses from /etc/resolv.conf");
info( " -S, --search LIST Space-separated list, search domains");
info( " a single, empty option disables the DNS search list");
if (strstr(name, "pasta"))
info( " default: don't use any search list");
else
info( " default: use search list from /etc/resolv.conf");
if (strstr(name, "pasta"))
info(" --dhcp-dns \tPass DNS list via DHCP/DHCPv6/NDP");
else
info(" --no-dhcp-dns No DNS list in DHCP/DHCPv6/NDP");
if (strstr(name, "pasta"))
info(" --dhcp-search Pass list via DHCP/DHCPv6/NDP");
else
info(" --no-dhcp-search No list in DHCP/DHCPv6/NDP");
info( " --dns-forward ADDR Forward DNS queries sent to ADDR");
info( " can be specified zero to two times (for IPv4 and IPv6)");
info( " default: don't forward DNS queries");
info( " --no-tcp Disable TCP protocol handler");
info( " --no-udp Disable UDP protocol handler");
info( " --no-icmp Disable ICMP/ICMPv6 protocol handler");
info( " --no-dhcp Disable DHCP server");
info( " --no-ndp Disable NDP responses");
info( " --no-dhcpv6 Disable DHCPv6 server");
info( " --no-ra Disable router advertisements");
info( " --no-map-gw Don't map gateway address to host");
info( " -4, --ipv4-only Enable IPv4 operation only");
info( " -6, --ipv6-only Enable IPv6 operation only");
if (strstr(name, "pasta"))
goto pasta_opts;
info( " -1, --one-off Quit after handling one single client");
info( " -t, --tcp-ports SPEC TCP port forwarding to guest");
info( " can be specified multiple times");
info( " SPEC can be:");
info( " 'none': don't forward any ports");
info( " 'all': forward all unbound, non-ephemeral ports");
info( " a comma-separated list, optionally ranged with '-'");
info( " and optional target ports after ':', with optional");
info( " address specification suffixed by '/' and optional");
info( " interface prefixed by '%%'. Ranges can be reduced by");
info( " excluding ports or ranges prefixed by '~'");
info( " Examples:");
info( " -t 22 Forward local port 22 to 22 on guest");
info( " -t 22:23 Forward local port 22 to 23 on guest");
info( " -t 22,25 Forward ports 22, 25 to ports 22, 25");
info( " -t 22-80 Forward ports 22 to 80");
info( " -t 22-80:32-90 Forward ports 22 to 80 to");
info( " corresponding port numbers plus 10");
info( " -t 192.0.2.1/5 Bind port 5 of 192.0.2.1 to guest");
info( " -t 5-25,~10-20 Forward ports 5 to 9, and 21 to 25");
info( " -t ~25 Forward all ports except for 25");
info( " default: none");
info( " -u, --udp-ports SPEC UDP port forwarding to guest");
info( " SPEC is as described for TCP above");
info( " default: none");
exit(EXIT_FAILURE);
pasta_opts:
info( " -t, --tcp-ports SPEC TCP port forwarding to namespace");
info( " can be specified multiple times");
info( " SPEC can be:");
info( " 'none': don't forward any ports");
info( " 'auto': forward all ports currently bound in namespace");
info( " a comma-separated list, optionally ranged with '-'");
info( " and optional target ports after ':', with optional");
info( " address specification suffixed by '/' and optional");
info( " interface prefixed by '%%'. Examples:");
info( " -t 22 Forward local port 22 to port 22 in netns");
info( " -t 22:23 Forward local port 22 to port 23");
info( " -t 22,25 Forward ports 22, 25 to ports 22, 25");
info( " -t 22-80 Forward ports 22 to 80");
info( " -t 22-80:32-90 Forward ports 22 to 80 to");
info( " corresponding port numbers plus 10");
info( " -t 192.0.2.1/5 Bind port 5 of 192.0.2.1 to namespace");
info( " -t 5-25,~10-20 Forward ports 5 to 9, and 21 to 25");
info( " -t ~25 Forward all bound ports except for 25");
info( " default: auto");
info( " IPv6 bound ports are also forwarded for IPv4");
info( " -u, --udp-ports SPEC UDP port forwarding to namespace");
info( " SPEC is as described for TCP above");
info( " default: auto");
info( " IPv6 bound ports are also forwarded for IPv4");
info( " unless specified, with '-t auto', UDP ports with numbers");
info( " corresponding to forwarded TCP port numbers are");
info( " forwarded too");
info( " -T, --tcp-ns SPEC TCP port forwarding to init namespace");
info( " SPEC is as described above");
info( " default: auto");
info( " -U, --udp-ns SPEC UDP port forwarding to init namespace");
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( " --no-netns-quit Don't quit if filesystem-bound target");
info( " network namespace is deleted");
info( " --config-net Configure tap interface in namespace");
info( " --ns-mac-addr ADDR Set MAC address on tap interface");
exit(EXIT_FAILURE);
}
/**
* conf_print() - Print fundamental configuration parameters
* @c: Execution context
*/
static void conf_print(const struct ctx *c)
{
char buf4[INET_ADDRSTRLEN], ifn[IFNAMSIZ];
int i;
if (c->ifi4)
info("Outbound interface (IPv4): %s", if_indextoname(c->ifi4, ifn));
if (c->ifi6)
info("Outbound interface (IPv6): %s", if_indextoname(c->ifi6, ifn));
if (c->mode == MODE_PASTA)
info("Namespace interface: %s", c->pasta_ifn);
info("MAC:");
info(" host: %02x:%02x:%02x:%02x:%02x:%02x",
c->mac[0], c->mac[1], c->mac[2],
c->mac[3], c->mac[4], c->mac[5]);
if (c->ifi4) {
if (!c->no_dhcp) {
info("DHCP:");
info(" assign: %s",
inet_ntop(AF_INET, &c->ip4.addr, buf4, sizeof(buf4)));
info(" mask: %s",
inet_ntop(AF_INET, &c->ip4.mask, buf4, sizeof(buf4)));
info(" router: %s",
inet_ntop(AF_INET, &c->ip4.gw, buf4, sizeof(buf4)));
}
for (i = 0; c->ip4.dns[i]; i++) {
if (!i)
info("DNS:");
inet_ntop(AF_INET, &c->ip4.dns[i], buf4, sizeof(buf4));
info(" %s", buf4);
}
for (i = 0; *c->dns_search[i].n; i++) {
if (!i)
info("DNS search list:");
info(" %s", c->dns_search[i].n);
}
}
if (c->ifi6) {
char buf6[INET6_ADDRSTRLEN];
if (!c->no_ndp && !c->no_dhcpv6)
info("NDP/DHCPv6:");
else if (!c->no_ndp)
info("DHCPv6:");
else if (!c->no_dhcpv6)
info("NDP:");
else
goto dns6;
info(" assign: %s",
inet_ntop(AF_INET6, &c->ip6.addr, buf6, sizeof(buf6)));
info(" router: %s",
inet_ntop(AF_INET6, &c->ip6.gw, buf6, sizeof(buf6)));
info(" our link-local: %s",
inet_ntop(AF_INET6, &c->ip6.addr_ll, buf6, sizeof(buf6)));
dns6:
for (i = 0; !IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns[i]); i++) {
if (!i)
info("DNS:");
inet_ntop(AF_INET6, &c->ip6.dns[i], buf6, sizeof(buf6));
info(" %s", buf6);
}
for (i = 0; *c->dns_search[i].n; i++) {
if (!i)
info("DNS search list:");
info(" %s", c->dns_search[i].n);
}
}
}
/**
* conf_runas() - Handle --runas: look up desired UID and GID
* @opt: Passed option value
* @uid: User ID, set on return if valid
* @gid: Group ID, set on return if valid
*
* Return: 0 on success, negative error code on failure
*/
static int conf_runas(char *opt, unsigned int *uid, unsigned int *gid)
{
const char *uopt, *gopt = NULL;
char *sep = strchr(opt, ':');
char *endptr;
if (sep) {
*sep = '\0';
gopt = sep + 1;
}
uopt = opt;
*gid = *uid = strtol(uopt, &endptr, 0);
if (*endptr) {
#ifndef GLIBC_NO_STATIC_NSS
/* Not numeric, look up as a username */
struct passwd *pw;
/* cppcheck-suppress getpwnamCalled */
if (!(pw = getpwnam(uopt)) || !(*uid = pw->pw_uid))
return -ENOENT;
*gid = pw->pw_gid;
#else
return -EINVAL;
#endif
}
if (!gopt)
return 0;
*gid = strtol(gopt, &endptr, 0);
if (*endptr) {
#ifndef GLIBC_NO_STATIC_NSS
/* Not numeric, look up as a group name */
struct group *gr;
/* cppcheck-suppress getgrnamCalled */
if (!(gr = getgrnam(gopt)))
return -ENOENT;
*gid = gr->gr_gid;
#else
return -EINVAL;
#endif
}
return 0;
}
/**
* conf_ugid() - Determine UID and GID to run as
* @runas: --runas option, may be NULL
* @uid: User ID, set on success
* @gid: Group ID, set on success
*
* Return: 0 on success, negative error code on failure
*/
static int conf_ugid(char *runas, uid_t *uid, gid_t *gid)
{
const char root_uid_map[] = " 0 0 4294967295";
char buf[BUFSIZ];
int ret;
int fd;
/* If user has specified --runas, that takes precedence... */
if (runas) {
ret = conf_runas(runas, uid, gid);
if (ret)
err("Invalid --runas option: %s", runas);
return ret;
}
/* ...otherwise default to current user and group... */
*uid = geteuid();
*gid = getegid();
/* ...as long as it's not root... */
if (*uid)
return 0;
/* ...or at least not root in the init namespace... */
if ((fd = open("/proc/self/uid_map", O_RDONLY | O_CLOEXEC)) < 0) {
ret = -errno;
err("Can't determine if we're in init namespace: %s",
strerror(-ret));
return ret;
}
if (read(fd, buf, BUFSIZ) != sizeof(root_uid_map) ||
strncmp(buf, root_uid_map, sizeof(root_uid_map) - 1)) {
close(fd);
return 0;
}
close(fd);
/* ...otherwise use nobody:nobody */
warn("Don't run as root. Changing to nobody...");
{
#ifndef GLIBC_NO_STATIC_NSS
struct passwd *pw;
/* cppcheck-suppress getpwnamCalled */
pw = getpwnam("nobody");
if (!pw) {
perror("getpwnam");
exit(EXIT_FAILURE);
}
*uid = pw->pw_uid;
*gid = pw->pw_gid;
#else
/* Common value for 'nobody', not really specified */
*uid = *gid = 65534;
#endif
}
return 0;
}
/**
* conf() - Process command-line arguments and set configuration
* @c: Execution context
* @argc: Argument count
* @argv: Options, plus target PID for pasta mode
*/
void conf(struct ctx *c, int argc, char **argv)
{
int netns_only = 0;
struct option options[] = {
{"debug", no_argument, NULL, 'd' },
{"quiet", no_argument, NULL, 'q' },
{"foreground", no_argument, NULL, 'f' },
{"stderr", no_argument, NULL, 'e' },
{"log-file", required_argument, NULL, 'l' },
{"help", no_argument, NULL, 'h' },
{"socket", required_argument, NULL, 's' },
{"ns-ifname", required_argument, NULL, 'I' },
{"pcap", required_argument, NULL, 'p' },
{"pid", required_argument, NULL, 'P' },
{"mtu", required_argument, NULL, 'm' },
{"address", required_argument, NULL, 'a' },
{"netmask", required_argument, NULL, 'n' },
{"mac-addr", required_argument, NULL, 'M' },
{"gateway", required_argument, NULL, 'g' },
{"interface", required_argument, NULL, 'i' },
{"dns", required_argument, NULL, 'D' },
{"search", required_argument, NULL, 'S' },
{"no-tcp", no_argument, &c->no_tcp, 1 },
{"no-udp", no_argument, &c->no_udp, 1 },
{"no-icmp", no_argument, &c->no_icmp, 1 },
{"no-dhcp", no_argument, &c->no_dhcp, 1 },
{"no-dhcpv6", no_argument, &c->no_dhcpv6, 1 },
{"no-ndp", no_argument, &c->no_ndp, 1 },
{"no-ra", no_argument, &c->no_ra, 1 },
{"no-map-gw", no_argument, &c->no_map_gw, 1 },
{"ipv4-only", no_argument, NULL, '4' },
{"ipv6-only", no_argument, NULL, '6' },
{"one-off", no_argument, NULL, '1' },
{"tcp-ports", required_argument, NULL, 't' },
{"udp-ports", required_argument, NULL, 'u' },
{"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, &netns_only, 1 },
{"config-net", no_argument, &c->pasta_conf_ns, 1 },
{"ns-mac-addr", required_argument, NULL, 4 },
{"dhcp-dns", no_argument, NULL, 5 },
{"no-dhcp-dns", no_argument, NULL, 6 },
{"dhcp-search", no_argument, NULL, 7 },
{"no-dhcp-search", no_argument, NULL, 8 },
{"dns-forward", required_argument, NULL, 9 },
{"no-netns-quit", no_argument, NULL, 10 },
{"trace", no_argument, NULL, 11 },
{"runas", required_argument, NULL, 12 },
{"log-size", required_argument, NULL, 13 },
{"version", no_argument, NULL, 14 },
{ 0 },
};
struct get_bound_ports_ns_arg ns_ports_arg = { .c = c };
char userns[PATH_MAX] = { 0 }, netns[PATH_MAX] = { 0 };
bool v4_only = false, v6_only = false;
char *runas = NULL, *logfile = NULL;
struct in6_addr *dns6 = c->ip6.dns;
struct fqdn *dnss = c->dns_search;
uint32_t *dns4 = c->ip4.dns;
int name, ret, mask, b, i;
const char *optstring;
unsigned int ifi = 0;
size_t logsize = 0;
uid_t uid;
gid_t gid;
if (c->mode == MODE_PASTA) {
c->no_dhcp_dns = c->no_dhcp_dns_search = 1;
optstring = "dqfel:hI:p:P:m:a:n:M:g:i:D:S:46t:u:T:U:";
} else {
optstring = "dqfel:hs:p:P:m:a:n:M:g:i:D:S:461t:u:";
}
c->tcp.fwd_in.mode = c->tcp.fwd_out.mode = 0;
c->udp.fwd_in.f.mode = c->udp.fwd_out.f.mode = 0;
do {
name = getopt_long(argc, argv, optstring, options, NULL);
switch (name) {
case -1:
case 0:
break;
case 2:
if (c->mode != MODE_PASTA) {
err("--userns is for pasta mode only");
usage(argv[0]);
}
ret = snprintf(userns, sizeof(userns), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(userns)) {
err("Invalid userns: %s", optarg);
usage(argv[0]);
}
break;
case 3:
if (c->mode != MODE_PASTA) {
err("--netns is for pasta mode only");
usage(argv[0]);
}
ret = conf_netns_opt(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");
usage(argv[0]);
}
for (i = 0; i < ETH_ALEN; i++) {
errno = 0;
b = strtol(optarg + (intptr_t)i * 3, NULL, 16);
if (b < 0 || b > UCHAR_MAX || errno) {
err("Invalid MAC address: %s", optarg);
usage(argv[0]);
}
c->mac_guest[i] = b;
}
break;
case 5:
if (c->mode != MODE_PASTA) {
err("--dhcp-dns is for pasta mode only");
usage(argv[0]);
}
c->no_dhcp_dns = 0;
break;
case 6:
if (c->mode != MODE_PASST) {
err("--no-dhcp-dns is for passt mode only");
usage(argv[0]);
}
c->no_dhcp_dns = 1;
break;
case 7:
if (c->mode != MODE_PASTA) {
err("--dhcp-search is for pasta mode only");
usage(argv[0]);
}
c->no_dhcp_dns_search = 0;
break;
case 8:
if (c->mode != MODE_PASST) {
err("--no-dhcp-search is for passt mode only");
usage(argv[0]);
}
c->no_dhcp_dns_search = 1;
break;
case 9:
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_fwd) &&
inet_pton(AF_INET6, optarg, &c->ip6.dns_fwd) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_fwd) &&
!IN6_IS_ADDR_LOOPBACK(&c->ip6.dns_fwd))
break;
if (c->ip4.dns_fwd == INADDR_ANY &&
inet_pton(AF_INET, optarg, &c->ip4.dns_fwd) &&
c->ip4.dns_fwd != INADDR_ANY &&
c->ip4.dns_fwd != INADDR_BROADCAST &&
c->ip4.dns_fwd != INADDR_LOOPBACK)
break;
err("Invalid DNS forwarding address: %s", optarg);
usage(argv[0]);
break;
case 10:
if (c->mode != MODE_PASTA) {
err("--no-netns-quit is for pasta mode only");
usage(argv[0]);
}
c->no_netns_quit = 1;
break;
case 11:
if (c->trace) {
err("Multiple --trace options given");
usage(argv[0]);
}
if (c->quiet) {
err("Either --trace or --quiet");
usage(argv[0]);
}
c->trace = c->debug = c->foreground = 1;
break;
case 12:
if (runas) {
err("Multiple --runas options given");
usage(argv[0]);
}
runas = optarg;
break;
case 13:
if (logsize) {
err("Multiple --log-size options given");
usage(argv[0]);
}
errno = 0;
logsize = strtol(optarg, NULL, 0);
if (logsize < LOGFILE_SIZE_MIN || errno) {
err("Invalid --log-size: %s", optarg);
usage(argv[0]);
}
break;
case 14:
fprintf(stdout,
c->mode == MODE_PASST ? "passt " : "pasta ");
fprintf(stdout, VERSION_BLOB);
exit(EXIT_SUCCESS);
case 'd':
if (c->debug) {
err("Multiple --debug options given");
usage(argv[0]);
}
if (c->quiet) {
err("Either --debug or --quiet");
usage(argv[0]);
}
c->debug = 1;
c->foreground = 1;
break;
case 'e':
if (logfile) {
err("Can't log to both file and stderr");
usage(argv[0]);
}
if (c->stderr) {
err("Multiple --stderr options given");
usage(argv[0]);
}
c->stderr = 1;
break;
case 'l':
if (c->stderr) {
err("Can't log to both stderr and file");
usage(argv[0]);
}
if (logfile) {
err("Multiple --log-file options given");
usage(argv[0]);
}
logfile = optarg;
break;
case 'q':
if (c->quiet) {
err("Multiple --quiet options given");
usage(argv[0]);
}
if (c->debug) {
err("Either --debug or --quiet");
usage(argv[0]);
}
c->quiet = 1;
break;
case 'f':
if (c->foreground && !c->debug) {
err("Multiple --foreground options given");
usage(argv[0]);
}
c->foreground = 1;
break;
case 's':
if (*c->sock_path) {
err("Multiple --socket options given");
usage(argv[0]);
}
ret = snprintf(c->sock_path, UNIX_SOCK_MAX - 1, "%s",
optarg);
if (ret <= 0 || ret >= (int)sizeof(c->sock_path)) {
err("Invalid socket path: %s", optarg);
usage(argv[0]);
}
break;
case 'I':
if (*c->pasta_ifn) {
err("Multiple --ns-ifname options given");
usage(argv[0]);
}
ret = snprintf(c->pasta_ifn, IFNAMSIZ - 1, "%s",
optarg);
if (ret <= 0 || ret >= IFNAMSIZ - 1) {
err("Invalid interface name: %s", optarg);
usage(argv[0]);
}
break;
case 'p':
if (*c->pcap) {
err("Multiple --pcap options given");
usage(argv[0]);
}
ret = snprintf(c->pcap, sizeof(c->pcap), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(c->pcap)) {
err("Invalid pcap path: %s", optarg);
usage(argv[0]);
}
break;
case 'P':
if (*c->pid_file) {
err("Multiple --pid options given");
usage(argv[0]);
}
ret = snprintf(c->pid_file, sizeof(c->pid_file), "%s",
optarg);
if (ret <= 0 || ret >= (int)sizeof(c->pid_file)) {
err("Invalid PID file: %s", optarg);
usage(argv[0]);
}
break;
case 'm':
if (c->mtu) {
err("Multiple --mtu options given");
usage(argv[0]);
}
errno = 0;
c->mtu = strtol(optarg, NULL, 0);
if (!c->mtu) {
c->mtu = -1;
break;
}
if (c->mtu < ETH_MIN_MTU || c->mtu > (int)ETH_MAX_MTU ||
errno) {
err("Invalid MTU: %s", optarg);
usage(argv[0]);
}
break;
case 'a':
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr) &&
inet_pton(AF_INET6, optarg, &c->ip6.addr) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr) &&
!IN6_IS_ADDR_LOOPBACK(&c->ip6.addr) &&
!IN6_IS_ADDR_V4MAPPED(&c->ip6.addr) &&
!IN6_IS_ADDR_V4COMPAT(&c->ip6.addr) &&
!IN6_IS_ADDR_MULTICAST(&c->ip6.addr))
break;
if (c->ip4.addr == INADDR_ANY &&
inet_pton(AF_INET, optarg, &c->ip4.addr) &&
c->ip4.addr != INADDR_ANY &&
c->ip4.addr != INADDR_BROADCAST &&
c->ip4.addr != INADDR_LOOPBACK &&
!IN_MULTICAST(c->ip4.addr))
break;
err("Invalid address: %s", optarg);
usage(argv[0]);
break;
case 'n':
if (inet_pton(AF_INET, optarg, &c->ip4.mask))
break;
errno = 0;
mask = strtol(optarg, NULL, 0);
if (mask > 0 && mask <= 32 && !errno) {
c->ip4.mask = htonl(0xffffffff << (32 - mask));
break;
}
err("Invalid netmask: %s", optarg);
usage(argv[0]);
break;
case 'M':
for (i = 0; i < ETH_ALEN; i++) {
errno = 0;
b = strtol(optarg + (intptr_t)i * 3, NULL, 16);
if (b < 0 || b > UCHAR_MAX || errno) {
err("Invalid MAC address: %s", optarg);
usage(argv[0]);
}
c->mac[i] = b;
}
break;
case 'g':
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.gw) &&
inet_pton(AF_INET6, optarg, &c->ip6.gw) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.gw) &&
!IN6_IS_ADDR_LOOPBACK(&c->ip6.gw))
break;
if (c->ip4.gw == INADDR_ANY &&
inet_pton(AF_INET, optarg, &c->ip4.gw) &&
c->ip4.gw != INADDR_ANY &&
c->ip4.gw != INADDR_BROADCAST &&
c->ip4.gw != INADDR_LOOPBACK)
break;
err("Invalid gateway address: %s", optarg);
usage(argv[0]);
break;
case 'i':
if (ifi) {
err("Redundant interface: %s", optarg);
usage(argv[0]);
}
if (!(ifi = if_nametoindex(optarg))) {
err("Invalid interface name %s: %s", optarg,
strerror(errno));
usage(argv[0]);
}
break;
case 'D':
if (!strcmp(optarg, "none")) {
if (c->no_dns) {
err("Redundant DNS options");
usage(argv[0]);
}
if (dns4 - c->ip4.dns || dns6 - c->ip6.dns) {
err("Conflicting DNS options");
usage(argv[0]);
}
c->no_dns = 1;
break;
}
if (c->no_dns) {
err("Conflicting DNS options");
usage(argv[0]);
}
if (dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) &&
inet_pton(AF_INET, optarg, dns4)) {
dns4++;
break;
}
if (dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) &&
inet_pton(AF_INET6, optarg, dns6)) {
dns6++;
break;
}
err("Cannot use DNS address %s", optarg);
usage(argv[0]);
break;
case 'S':
if (!strcmp(optarg, "none")) {
if (c->no_dns_search) {
err("Redundant DNS search options");
usage(argv[0]);
}
if (dnss != c->dns_search) {
err("Conflicting DNS search options");
usage(argv[0]);
}
c->no_dns_search = 1;
break;
}
if (c->no_dns_search) {
err("Conflicting DNS search options");
usage(argv[0]);
}
if (dnss - c->dns_search < ARRAY_SIZE(c->dns_search)) {
ret = snprintf(dnss->n, sizeof(*c->dns_search),
"%s", optarg);
dnss++;
if (ret > 0 &&
ret < (int)sizeof(*c->dns_search))
break;
}
err("Cannot use DNS search domain %s", optarg);
usage(argv[0]);
break;
case '4':
v4_only = true;
break;
case '6':
v6_only = true;
break;
case '1':
if (c->mode != MODE_PASST) {
err("--one-off is for passt mode only");
usage(argv[0]);
}
if (c->one_off) {
err("Redundant --one-off option");
usage(argv[0]);
}
c->one_off = true;
break;
case 't':
case 'u':
case 'T':
case 'U':
/* Handle these later, once addresses are configured */
break;
case '?':
case 'h':
default:
usage(argv[0]);
break;
}
} while (name != -1);
if (v4_only && v6_only) {
err("Options ipv4-only and ipv6-only are mutually exclusive");
usage(argv[0]);
}
ret = conf_ugid(runas, &uid, &gid);
if (ret)
usage(argv[0]);
if (logfile) {
logfile_init(c->mode == MODE_PASST ? "passt" : "pasta",
logfile, logsize);
}
nl_sock_init(c, false);
if (!v6_only)
c->ifi4 = conf_ip4(ifi, &c->ip4, c->mac);
if (!v4_only)
c->ifi6 = conf_ip6(ifi, &c->ip6, c->mac);
if (!c->ifi4 && !c->ifi6) {
err("External interface not usable");
exit(EXIT_FAILURE);
}
/* Inbound port options can be parsed now (after IPv4/IPv6 settings) */
optind = 1;
do {
struct port_fwd *fwd;
name = getopt_long(argc, argv, optstring, options, NULL);
if ((name == 't' && (fwd = &c->tcp.fwd_in)) ||
(name == 'u' && (fwd = &c->udp.fwd_in.f))) {
if (!optarg || conf_ports(c, name, optarg, fwd))
usage(argv[0]);
}
} while (name != -1);
if (c->mode == MODE_PASTA) {
if (conf_pasta_ns(&netns_only, userns, netns,
optind, argc, argv) < 0)
usage(argv[0]);
} else if (optind != argc) {
usage(argv[0]);
}
isolate_user(uid, gid, !netns_only, userns, c->mode);
if (c->pasta_conf_ns)
c->no_ra = 1;
if (c->mode == MODE_PASTA) {
if (*netns) {
pasta_open_ns(c, netns);
} else {
pasta_start_ns(c, uid, gid,
argc - optind, argv + optind);
}
}
if (c->mode == MODE_PASTA)
nl_sock_init(c, true);
/* ...and outbound port options now that namespaces are set up. */
optind = 1;
do {
struct port_fwd *fwd;
name = getopt_long(argc, argv, optstring, options, NULL);
if ((name == 'T' && (fwd = &c->tcp.fwd_out)) ||
(name == 'U' && (fwd = &c->udp.fwd_out.f))) {
if (!optarg || conf_ports(c, name, optarg, fwd))
usage(argv[0]);
}
} while (name != -1);
if (!c->ifi4)
c->no_dhcp = 1;
if (!c->ifi6) {
c->no_ndp = 1;
c->no_dhcpv6 = 1;
}
if (!c->mtu)
c->mtu = ROUND_DOWN(ETH_MAX_MTU - ETH_HLEN, sizeof(uint32_t));
get_dns(c);
if (!*c->pasta_ifn) {
if (c->ifi4)
if_indextoname(c->ifi4, c->pasta_ifn);
else
if_indextoname(c->ifi6, c->pasta_ifn);
}
if (c->mode == MODE_PASTA) {
c->proc_net_tcp[V4][0] = c->proc_net_tcp[V4][1] = -1;
c->proc_net_tcp[V6][0] = c->proc_net_tcp[V6][1] = -1;
c->proc_net_udp[V4][0] = c->proc_net_udp[V4][1] = -1;
c->proc_net_udp[V6][0] = c->proc_net_udp[V6][1] = -1;
if (!c->tcp.fwd_in.mode || c->tcp.fwd_in.mode == FWD_AUTO) {
c->tcp.fwd_in.mode = FWD_AUTO;
ns_ports_arg.proto = IPPROTO_TCP;
NS_CALL(get_bound_ports_ns, &ns_ports_arg);
}
if (!c->udp.fwd_in.f.mode || c->udp.fwd_in.f.mode == FWD_AUTO) {
c->udp.fwd_in.f.mode = FWD_AUTO;
ns_ports_arg.proto = IPPROTO_UDP;
NS_CALL(get_bound_ports_ns, &ns_ports_arg);
}
if (!c->tcp.fwd_out.mode || c->tcp.fwd_out.mode == FWD_AUTO) {
c->tcp.fwd_out.mode = FWD_AUTO;
get_bound_ports(c, 0, IPPROTO_TCP);
}
if (!c->udp.fwd_out.f.mode || c->udp.fwd_out.f.mode == FWD_AUTO) {
c->udp.fwd_out.f.mode = FWD_AUTO;
get_bound_ports(c, 0, IPPROTO_UDP);
}
} else {
if (!c->tcp.fwd_in.mode)
c->tcp.fwd_in.mode = FWD_NONE;
if (!c->tcp.fwd_out.mode)
c->tcp.fwd_out.mode = FWD_NONE;
if (!c->udp.fwd_in.f.mode)
c->udp.fwd_in.f.mode = FWD_NONE;
if (!c->udp.fwd_out.f.mode)
c->udp.fwd_out.f.mode = FWD_NONE;
}
if (!c->quiet)
conf_print(c);
}