passt/conf.c
Stefano Brivio 2fe0461856 netlink: Add functionality to copy routes from outer namespace
Instead of just fetching the default gateway and configuring a single
equivalent route in the target namespace, on 'pasta --config-net', it
might be desirable in some cases to copy the whole set of routes
corresponding to a given output interface.

For instance, in:
  https://github.com/containers/podman/issues/18539
  IPv4 Default Route Does Not Propagate to Pasta Containers on Hetzner VPSes

configuring the default gateway won't work without a gateway-less
route (specifying the output interface only), because the default
gateway is, somewhat dubiously, not on the same subnet as the
container.

This is a similar case to the one covered by commit 7656a6f888
("conf: Adjust netmask on mismatch between IPv4 address/netmask and
gateway"), and I'm not exactly proud of that workaround.

We also have:
  https://bugs.passt.top/show_bug.cgi?id=49
  pasta does not work with tap-style interface

for which, eventually, we should be able to configure a gateway-less
route in the target namespace.

Introduce different operation modes for nl_route(), including a new
NL_DUP one, not exposed yet, which simply parrots back to the kernel
the route dump for a given interface from the outer namespace, fixing
up flags and interface indices on the way, and requesting to add the
same routes in the target namespace, on the interface we manage.

For n routes we want to duplicate, send n identical netlink requests
including the full dump: routes might depend on each other and the
kernel processes RTM_NEWROUTE messages sequentially, not atomically,
and repeating the full dump naturally resolves dependencies without
the need to actually calculate them.

I'm not kidding, it actually works pretty well.

Link: https://github.com/containers/podman/issues/18539
Link: https://bugs.passt.top/show_bug.cgi?id=49
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-05-23 16:13:28 +02:00

1769 lines
48 KiB
C

// 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
*
* 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 <unistd.h>
#include <signal.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <stdbool.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
*
* Return: 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
*/
static void 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;
bool exclude_only = true, bound_one = false;
uint8_t exclude[PORT_BITMAP_SIZE] = { 0 };
sa_family_t af = AF_UNSPEC;
int ret;
if (!strcmp(optarg, "none")) {
if (fwd->mode)
goto mode_conflict;
fwd->mode = FWD_NONE;
return;
}
if (!strcmp(optarg, "auto")) {
if (fwd->mode)
goto mode_conflict;
if (c->mode != MODE_PASTA)
die("'auto' port forwarding is only allowed for pasta");
fwd->mode = FWD_AUTO;
return;
}
if (!strcmp(optarg, "all")) {
unsigned i;
if (fwd->mode)
goto mode_conflict;
if (c->mode != MODE_PASST)
die("'all' port forwarding is only allowed for passt");
fwd->mode = FWD_ALL;
memset(fwd->map, 0xff, PORT_EPHEMERAL_MIN / 8);
for (i = 0; i < PORT_EPHEMERAL_MIN; i++) {
if (optname == 't') {
ret = tcp_sock_init(c, AF_UNSPEC, NULL, NULL,
i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
} else if (optname == 'u') {
ret = udp_sock_init(c, 0, AF_UNSPEC, NULL, NULL,
i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
}
}
if (!bound_one)
goto bind_fail;
return;
}
if (fwd->mode > FWD_SPEC)
die("Specific ports cannot be specified together with all/none/auto");
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 (ifname == buf + 1) /* Interface without address */
addr = NULL;
else 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;
}
p++;
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') {
ret = tcp_sock_init(c, af, addr, ifname, i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
} else if (optname == 'u') {
ret = udp_sock_init(c, 0, af, addr, ifname, i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
} else {
/* No way to check in advance for -T and -U */
bound_one = true;
}
}
if (!bound_one)
goto bind_fail;
return;
}
/* 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') {
ret = tcp_sock_init(c, af, addr, ifname, i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
} else if (optname == 'u') {
ret = udp_sock_init(c, 0, af, addr, ifname, i);
if (ret == -ENFILE || ret == -EMFILE)
goto enfile;
if (!ret)
bound_one = true;
} else {
/* No way to check in advance for -T and -U */
bound_one = true;
}
}
} while ((p = next_chunk(p, ',')));
if (!bound_one)
goto bind_fail;
return;
enfile:
die("Can't open enough sockets for port specifier: %s", optarg);
bad:
die("Invalid port specifier %s", optarg);
overlap:
die("Overlapping port specifier %s", optarg);
mode_conflict:
die("Port forwarding mode '%s' conflicts with previous mode", optarg);
bind_fail:
die("Failed to bind any port for '-%c %s', exiting", optname, optarg);
}
/**
* add_dns4() - Possibly add the IPv4 address of a DNS resolver to configuration
* @c: Execution context
* @addr: Address found in /etc/resolv.conf
* @conf: Pointer to reference of current entry in array of IPv4 resolvers
*/
static void add_dns4(struct ctx *c, struct in_addr *addr, struct in_addr **conf)
{
/* Guest or container can only access local addresses via redirect */
if (IN4_IS_ADDR_LOOPBACK(addr)) {
if (!c->no_map_gw) {
**conf = c->ip4.gw;
(*conf)++;
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
c->ip4.dns_match = c->ip4.gw;
}
} else {
**conf = *addr;
(*conf)++;
}
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
c->ip4.dns_host = *addr;
}
/**
* add_dns6() - Possibly add the IPv6 address of a DNS resolver to configuration
* @c: Execution context
* @addr: Address found in /etc/resolv.conf
* @conf: Pointer to reference of current entry in array of IPv6 resolvers
*/
static void add_dns6(struct ctx *c,
struct in6_addr *addr, struct in6_addr **conf)
{
/* Guest or container can only access local addresses via redirect */
if (IN6_IS_ADDR_LOOPBACK(addr)) {
if (!c->no_map_gw) {
memcpy(*conf, &c->ip6.gw, sizeof(**conf));
(*conf)++;
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
memcpy(&c->ip6.dns_match, addr, sizeof(*addr));
}
} else {
memcpy(*conf, addr, sizeof(**conf));
(*conf)++;
}
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
c->ip6.dns_host = *addr;
}
/**
* get_dns() - Get nameserver addresses from local /etc/resolv.conf
* @c: Execution context
*/
static void get_dns(struct ctx *c)
{
struct in6_addr *dns6 = &c->ip6.dns[0], dns6_tmp;
struct in_addr *dns4 = &c->ip4.dns[0], dns4_tmp;
int dns4_set, dns6_set, dnss_set, dns_set, fd;
struct fqdn *s = c->dns_search;
struct lineread resolvconf;
int line_len;
char *line, *p, *end;
dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(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_tmp))
add_dns4(c, &dns4_tmp, &dns4);
if (!dns6_set &&
dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) - 1
&& inet_pton(AF_INET6, p + 1, &dns6_tmp))
add_dns6(c, &dns6_tmp, &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
*/
static void 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)
die("Network namespace name/path %s too long");
}
/**
* 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
*/
static void conf_pasta_ns(int *netns_only, char *userns, char *netns,
int optind, int argc, char *argv[])
{
if (*netns_only && *userns)
die("Both --userns and --netns-only given");
if (*netns && optind != argc)
die("Both --netns and PID or command given");
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)
die("Invalid PID %s", argv[optind]);
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;
}
/** conf_ip4_prefix() - Parse an IPv4 prefix length or netmask
* @arg: Netmask in dotted decimal or prefix length
*
* Return: Validated prefix length on success, -1 on failure
*/
static int conf_ip4_prefix(const char *arg)
{
struct in_addr mask;
unsigned long len;
if (inet_pton(AF_INET, arg, &mask)) {
in_addr_t hmask = ntohl(mask.s_addr);
len = __builtin_popcount(hmask);
if ((hmask << len) != 0)
return -1;
} else {
errno = 0;
len = strtoul(optarg, NULL, 0);
if (len > 32 || errno)
return -1;
}
return len;
}
/**
* 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)
{
in_addr_t addr, gw;
int shift;
if (!ifi)
ifi = nl_get_ext_if(AF_INET);
if (!ifi) {
warn("No external routable interface for IPv4");
return 0;
}
if (IN4_IS_ADDR_UNSPECIFIED(&ip4->gw))
nl_route(NL_GET, ifi, 0, AF_INET, &ip4->gw);
if (IN4_IS_ADDR_UNSPECIFIED(&ip4->addr))
nl_addr(0, ifi, AF_INET, &ip4->addr, &ip4->prefix_len, NULL);
addr = ntohl(ip4->addr.s_addr);
gw = ntohl(ip4->gw.s_addr);
if (!ip4->prefix_len) {
if (IN_CLASSA(addr))
ip4->prefix_len = (32 - IN_CLASSA_NSHIFT);
else if (IN_CLASSB(addr))
ip4->prefix_len = (32 - IN_CLASSB_NSHIFT);
else if (IN_CLASSC(addr))
ip4->prefix_len = (32 - IN_CLASSC_NSHIFT);
else
ip4->prefix_len = 32;
}
/* We might get an address with a netmask that makes the default
* gateway unreachable, and in that case we would fail to configure
* the default route, with --config-net, or presumably a DHCP client
* in the guest or container would face the same issue.
*
* The host might have another route, to the default gateway itself,
* fixing the situation, but we only read default routes.
*
* Fix up the mask to allow reaching the default gateway from our
* configured address, if needed, and only if we find a non-zero
* mask that makes the gateway reachable.
*/
shift = 32 - ip4->prefix_len;
while (shift < 32 && addr >> shift != gw >> shift)
shift++;
if (shift < 32)
ip4->prefix_len = 32 - shift;
memcpy(&ip4->addr_seen, &ip4->addr, sizeof(ip4->addr_seen));
if (MAC_IS_ZERO(mac))
nl_link(0, ifi, mac, 0, 0);
if (IN4_IS_ADDR_UNSPECIFIED(&ip4->gw) ||
IN4_IS_ADDR_UNSPECIFIED(&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(NL_GET, ifi, 0, 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");
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( " -F, --fd FD Use FD as pre-opened connected socket");
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: from --outbound-if4 and --outbound-if6, if any");
info( " otherwise interface with first default route");
info( " -o, --outbound ADDR Bind to address as outbound source");
info( " can be specified zero to two times (for IPv4 and IPv6)");
info( " default: use source address from routing tables");
info( " --outbound-if4 NAME Bind to outbound interface for IPv4");
info( " default: use interface from default route");
info( " --outbound-if6 NAME Bind to outbound interface for IPv6");
info( " default: use interface from 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], buf6[INET6_ADDRSTRLEN], ifn[IFNAMSIZ];
int i;
info("Template interface: %s%s%s%s%s",
c->ifi4 ? if_indextoname(c->ifi4, ifn) : "",
c->ifi4 ? " (IPv4)" : "",
(c->ifi4 && c->ifi6) ? ", " : "",
c->ifi6 ? if_indextoname(c->ifi6, ifn) : "",
c->ifi6 ? " (IPv6)" : "");
if (*c->ip4.ifname_out || *c->ip6.ifname_out) {
info("Outbound interface: %s%s%s%s%s",
*c->ip4.ifname_out ? c->ip4.ifname_out : "",
*c->ip4.ifname_out ? " (IPv4)" : "",
(*c->ip4.ifname_out && *c->ip6.ifname_out) ? ", " : "",
*c->ip6.ifname_out ? c->ip6.ifname_out : "",
*c->ip6.ifname_out ? " (IPv6)" : "");
}
if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr_out) ||
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr_out)) {
info("Outbound address: %s%s%s",
IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr_out) ? "" :
inet_ntop(AF_INET, &c->ip4.addr_out, buf4, sizeof(buf4)),
(!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr_out) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr_out)) ? ", " : "",
IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr_out) ? "" :
inet_ntop(AF_INET6, &c->ip6.addr_out, buf6, sizeof(buf6)));
}
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) {
uint32_t mask;
mask = htonl(0xffffffff << (32 - c->ip4.prefix_len));
info("DHCP:");
info(" assign: %s",
inet_ntop(AF_INET, &c->ip4.addr, buf4, sizeof(buf4)));
info(" mask: %s",
inet_ntop(AF_INET, &mask, buf4, sizeof(buf4)));
info(" router: %s",
inet_ntop(AF_INET, &c->ip4.gw, buf4, sizeof(buf4)));
}
for (i = 0; !IN4_IS_ADDR_UNSPECIFIED(&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) {
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
*/
static void conf_ugid(char *runas, uid_t *uid, gid_t *gid)
{
/* If user has specified --runas, that takes precedence... */
if (runas) {
if (conf_runas(runas, uid, gid))
die("Invalid --runas option: %s", runas);
return;
}
/* ...otherwise default to current user and group... */
*uid = geteuid();
*gid = getegid();
/* ...as long as it's not root... */
if (*uid)
return;
/* ...or at least not root in the init namespace... */
if (!ns_is_init())
return;
/* ...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
}
}
/**
* 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' },
{"fd", required_argument, NULL, 'F' },
{"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' },
{"outbound", required_argument, NULL, 'o' },
{"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 },
{"outbound-if4", required_argument, NULL, 15 },
{"outbound-if6", required_argument, NULL, 16 },
{ 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;
struct in_addr *dns4 = c->ip4.dns;
unsigned int ifi4 = 0, ifi6 = 0;
const char *optstring;
int name, ret, b, i;
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:hF:I:p:P:m:a:n:M:g:i:o:D:S:46t:u:T:U:";
} else {
optstring = "dqfel:hs:F:p:P:m:a:n:M:g:i:o: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)
die("--userns is for pasta mode only");
ret = snprintf(userns, sizeof(userns), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(userns))
die("Invalid userns: %s", optarg);
break;
case 3:
if (c->mode != MODE_PASTA)
die("--netns is for pasta mode only");
conf_netns_opt(netns, optarg);
break;
case 4:
if (c->mode != MODE_PASTA)
die("--ns-mac-addr is for pasta mode only");
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)
die("Invalid MAC address: %s", optarg);
c->mac_guest[i] = b;
}
break;
case 5:
if (c->mode != MODE_PASTA)
die("--dhcp-dns is for pasta mode only");
c->no_dhcp_dns = 0;
break;
case 6:
if (c->mode != MODE_PASST)
die("--no-dhcp-dns is for passt mode only");
c->no_dhcp_dns = 1;
break;
case 7:
if (c->mode != MODE_PASTA)
die("--dhcp-search is for pasta mode only");
c->no_dhcp_dns_search = 0;
break;
case 8:
if (c->mode != MODE_PASST)
die("--no-dhcp-search is for passt mode only");
c->no_dhcp_dns_search = 1;
break;
case 9:
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match) &&
inet_pton(AF_INET6, optarg, &c->ip6.dns_match) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match) &&
!IN6_IS_ADDR_LOOPBACK(&c->ip6.dns_match))
break;
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
inet_pton(AF_INET, optarg, &c->ip4.dns_match) &&
!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
!IN4_IS_ADDR_BROADCAST(&c->ip4.dns_match) &&
!IN4_IS_ADDR_LOOPBACK(&c->ip4.dns_match))
break;
die("Invalid DNS forwarding address: %s", optarg);
break;
case 10:
if (c->mode != MODE_PASTA)
die("--no-netns-quit is for pasta mode only");
c->no_netns_quit = 1;
break;
case 11:
if (c->trace)
die("Multiple --trace options given");
if (c->quiet)
die("Either --trace or --quiet");
c->trace = c->debug = 1;
break;
case 12:
if (runas)
die("Multiple --runas options given");
runas = optarg;
break;
case 13:
if (logsize)
die("Multiple --log-size options given");
errno = 0;
logsize = strtol(optarg, NULL, 0);
if (logsize < LOGFILE_SIZE_MIN || errno)
die("Invalid --log-size: %s", optarg);
break;
case 14:
fprintf(stdout,
c->mode == MODE_PASST ? "passt " : "pasta ");
fprintf(stdout, VERSION_BLOB);
exit(EXIT_SUCCESS);
case 15:
if (*c->ip4.ifname_out)
die("Redundant outbound interface: %s", optarg);
ret = snprintf(c->ip4.ifname_out,
sizeof(c->ip4.ifname_out), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(c->ip4.ifname_out))
die("Invalid interface name: %s", optarg);
break;
case 16:
if (*c->ip6.ifname_out)
die("Redundant outbound interface: %s", optarg);
ret = snprintf(c->ip6.ifname_out,
sizeof(c->ip6.ifname_out), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(c->ip6.ifname_out))
die("Invalid interface name: %s", optarg);
break;
case 'd':
if (c->debug)
die("Multiple --debug options given");
if (c->quiet)
die("Either --debug or --quiet");
c->debug = 1;
break;
case 'e':
if (logfile)
die("Can't log to both file and stderr");
if (c->force_stderr)
die("Multiple --stderr options given");
c->force_stderr = 1;
break;
case 'l':
if (c->force_stderr)
die("Can't log to both stderr and file");
if (logfile)
die("Multiple --log-file options given");
logfile = optarg;
break;
case 'q':
if (c->quiet)
die("Multiple --quiet options given");
if (c->debug)
die("Either --debug or --quiet");
c->quiet = 1;
break;
case 'f':
if (c->foreground)
die("Multiple --foreground options given");
c->foreground = 1;
break;
case 's':
if (*c->sock_path)
die("Multiple --socket options given");
ret = snprintf(c->sock_path, UNIX_SOCK_MAX - 1, "%s",
optarg);
if (ret <= 0 || ret >= (int)sizeof(c->sock_path))
die("Invalid socket path: %s", optarg);
break;
case 'F':
if (c->fd_tap >= 0)
die("Multiple --fd options given");
errno = 0;
c->fd_tap = strtol(optarg, NULL, 0);
if (c->fd_tap < 0 || errno)
die("Invalid --fd: %s", optarg);
c->one_off = true;
break;
case 'I':
if (*c->pasta_ifn)
die("Multiple --ns-ifname options given");
ret = snprintf(c->pasta_ifn, IFNAMSIZ - 1, "%s",
optarg);
if (ret <= 0 || ret >= IFNAMSIZ - 1)
die("Invalid interface name: %s", optarg);
break;
case 'p':
if (*c->pcap)
die("Multiple --pcap options given");
ret = snprintf(c->pcap, sizeof(c->pcap), "%s", optarg);
if (ret <= 0 || ret >= (int)sizeof(c->pcap))
die("Invalid pcap path: %s", optarg);
break;
case 'P':
if (*c->pid_file)
die("Multiple --pid options given");
ret = snprintf(c->pid_file, sizeof(c->pid_file), "%s",
optarg);
if (ret <= 0 || ret >= (int)sizeof(c->pid_file))
die("Invalid PID file: %s", optarg);
break;
case 'm':
if (c->mtu)
die("Multiple --mtu options given");
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)
die("Invalid MTU: %s", optarg);
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 (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr) &&
inet_pton(AF_INET, optarg, &c->ip4.addr) &&
!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr) &&
!IN4_IS_ADDR_BROADCAST(&c->ip4.addr) &&
!IN4_IS_ADDR_LOOPBACK(&c->ip4.addr) &&
!IN4_IS_ADDR_MULTICAST(&c->ip4.addr))
break;
die("Invalid address: %s", optarg);
break;
case 'n':
c->ip4.prefix_len = conf_ip4_prefix(optarg);
if (c->ip4.prefix_len < 0)
die("Invalid netmask: %s", optarg);
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)
die("Invalid MAC address: %s", optarg);
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 (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.gw) &&
inet_pton(AF_INET, optarg, &c->ip4.gw) &&
!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.gw) &&
!IN4_IS_ADDR_BROADCAST(&c->ip4.gw) &&
!IN4_IS_ADDR_LOOPBACK(&c->ip4.gw))
break;
die("Invalid gateway address: %s", optarg);
break;
case 'i':
if (ifi4 || ifi6)
die("Redundant interface: %s", optarg);
if (!(ifi4 = ifi6 = if_nametoindex(optarg)))
die("Invalid interface name %s: %s", optarg,
strerror(errno));
break;
case 'o':
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr_out) &&
inet_pton(AF_INET6, optarg, &c->ip6.addr_out) &&
!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr_out) &&
!IN6_IS_ADDR_LOOPBACK(&c->ip6.addr_out) &&
!IN6_IS_ADDR_V4MAPPED(&c->ip6.addr_out) &&
!IN6_IS_ADDR_V4COMPAT(&c->ip6.addr_out) &&
!IN6_IS_ADDR_MULTICAST(&c->ip6.addr_out))
break;
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr_out) &&
inet_pton(AF_INET, optarg, &c->ip4.addr_out) &&
!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addr_out) &&
!IN4_IS_ADDR_BROADCAST(&c->ip4.addr_out) &&
!IN4_IS_ADDR_MULTICAST(&c->ip4.addr_out))
break;
die("Invalid or redundant outbound address: %s",
optarg);
break;
case 'D':
if (!strcmp(optarg, "none")) {
if (c->no_dns)
die("Redundant DNS options");
if (dns4 - c->ip4.dns || dns6 - c->ip6.dns)
die("Conflicting DNS options");
c->no_dns = 1;
break;
}
if (c->no_dns)
die("Conflicting DNS options");
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;
}
die("Cannot use DNS address %s", optarg);
break;
case 'S':
if (!strcmp(optarg, "none")) {
if (c->no_dns_search)
die("Redundant DNS search options");
if (dnss != c->dns_search)
die("Conflicting DNS search options");
c->no_dns_search = 1;
break;
}
if (c->no_dns_search)
die("Conflicting DNS search options");
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;
}
die("Cannot use DNS search domain %s", optarg);
break;
case '4':
v4_only = true;
break;
case '6':
v6_only = true;
break;
case '1':
if (c->mode != MODE_PASST)
die("--one-off is for passt mode only");
if (c->one_off)
die("Redundant --one-off option");
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)
die("Options ipv4-only and ipv6-only are mutually exclusive");
if (*c->sock_path && c->fd_tap >= 0)
die("Options --socket and --fd are mutually exclusive");
if (!ifi4 && *c->ip4.ifname_out)
ifi4 = if_nametoindex(c->ip4.ifname_out);
if (!ifi6 && *c->ip6.ifname_out)
ifi6 = if_nametoindex(c->ip6.ifname_out);
conf_ugid(runas, &uid, &gid);
if (logfile) {
logfile_init(c->mode == MODE_PASST ? "passt" : "pasta",
logfile, logsize);
}
nl_sock_init(c, false);
if (!v6_only)
c->ifi4 = conf_ip4(ifi4, &c->ip4, c->mac);
if (!v4_only)
c->ifi6 = conf_ip6(ifi6, &c->ip6, c->mac);
if ((!c->ifi4 && !c->ifi6) ||
(*c->ip4.ifname_out && !c->ifi4) ||
(*c->ip6.ifname_out && !c->ifi6))
die("External interface not usable");
/* 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))) {
conf_ports(c, name, optarg, fwd);
}
} while (name != -1);
if (c->mode == MODE_PASTA)
conf_pasta_ns(&netns_only, userns, netns, optind, argc, argv);
else if (optind != argc)
die("Extra non-option argument: %s", argv[optind]);
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))) {
conf_ports(c, name, optarg, fwd);
}
} 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);
}