On Sun, Dec 14, 2025 at 08:54:30PM -0500, Jon Maloy wrote:
> As preparation for supporting multiple addresses per interface, we
> replace the single addr/prefix_len fields with arrays.
> 
> - We add an ip4_addr_entry and an ip6_addr_entry struct containing
>   address and prefix length.
> 
> - We set the array sizes to IP4_MAX_ADDRS=8 and IP6_MAX_ADDRS=16,
>   respectively.
> 
> The only functional change is that the IPv6 prefix length now is
> properly stored instead of being hardcoded to 64 even when set
> via the -a option.
> 
> Signed-off-by: Jon Maloy <jmaloy@redhat.com>
> ---
>  arp.c    |  4 +--
>  conf.c   | 97 +++++++++++++++++++++++++++++++++-----------------------
>  dhcp.c   |  8 ++---
>  dhcpv6.c |  6 ++--
>  fwd.c    | 12 +++----
>  ip.h     | 26 +++++++++++++++
>  ndp.c    |  6 ++--
>  passt.h  | 16 ++++++----
>  pasta.c  | 12 ++++---
>  tap.c    |  4 +--
>  util.h   |  1 +
>  11 files changed, 122 insertions(+), 70 deletions(-)
> 
> diff --git a/arp.c b/arp.c
> index bb042e9..7eaf517 100644
> --- a/arp.c
> +++ b/arp.c
> @@ -54,7 +54,7 @@ static bool ignore_arp(const struct ctx *c,
>  		return true;
>  
>  	/* Don't resolve the guest's assigned address, either. */
> -	if (!memcmp(am->tip, &c->ip4.addr, sizeof(am->tip)))
> +	if (!memcmp(am->tip, &c->ip4.addrs[0].addr, sizeof(am->tip)))
>  		return true;
>  
>  	return false;
> @@ -145,7 +145,7 @@ void arp_send_init_req(const struct ctx *c)
>  	memcpy(req.am.sha,	c->our_tap_mac,		sizeof(req.am.sha));
>  	memcpy(req.am.sip,	&c->ip4.our_tap_addr,	sizeof(req.am.sip));
>  	memcpy(req.am.tha,	MAC_BROADCAST,		sizeof(req.am.tha));
> -	memcpy(req.am.tip,	&c->ip4.addr,		sizeof(req.am.tip));
> +	memcpy(req.am.tip,	&c->ip4.addrs[0].addr,	sizeof(req.am.tip));
>  
>  	debug("Sending initial ARP request for guest MAC address");
>  	tap_send_single(c, &req, sizeof(req));
> diff --git a/conf.c b/conf.c
> index fdc19e8..0e96f36 100644
> --- a/conf.c
> +++ b/conf.c
> @@ -694,10 +694,12 @@ static int conf_ip4_prefix(const char *arg)
>   * 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)
> + * @permanent:	Mark configured addresses as permanent
>   *
>   * Return: interface index for IPv4, or 0 on failure.
>   */
> -static unsigned int conf_ip4(unsigned int ifi, struct ip4_ctx *ip4)
> +static unsigned int conf_ip4(unsigned int ifi, struct ip4_ctx *ip4,
> +			     bool permanent)
>  {
>  	if (!ifi)
>  		ifi = nl_get_ext_if(nl_sock, AF_INET);
> @@ -717,33 +719,38 @@ static unsigned int conf_ip4(unsigned int ifi, struct ip4_ctx *ip4)
>  		}
>  	}
>  
> -	if (IN4_IS_ADDR_UNSPECIFIED(&ip4->addr)) {
> +	if (!ip4->addr_count) {
>  		int rc = nl_addr_get(nl_sock, ifi, AF_INET,
> -				     &ip4->addr, &ip4->prefix_len, NULL);
> +				     &ip4->addrs[0].addr,
> +				     &ip4->addrs[0].prefix_len, NULL);
>  		if (rc < 0) {
>  			debug("Couldn't discover IPv4 address: %s",
>  			      strerror_(-rc));
>  			return 0;
>  		}
> +		ip4->addrs[0].permanent = permanent;
> +		ip4->addr_count = 1;
>  	}
>  
> -	if (!ip4->prefix_len) {
> -		in_addr_t addr = ntohl(ip4->addr.s_addr);
> -		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);
> +	/* Apply default prefix_len to first address if not set */
> +	if (!ip4->addrs[0].prefix_len) {
> +		in_addr_t a = ntohl(ip4->addrs[0].addr.s_addr);
> +
> +		if (IN_CLASSA(a))
> +			ip4->addrs[0].prefix_len = 8;
> +		else if (IN_CLASSB(a))
> +			ip4->addrs[0].prefix_len = 16;
> +		else if (IN_CLASSC(a))
> +			ip4->addrs[0].prefix_len = 24;
>  		else
> -			ip4->prefix_len = 32;
> +			ip4->addrs[0].prefix_len = 32;
>  	}
>  
> -	ip4->addr_seen = ip4->addr;
> +	ip4->addr_seen = ip4->addrs[0].addr;
>  
>  	ip4->our_tap_addr = ip4->guest_gw;
>  
> -	if (IN4_IS_ADDR_UNSPECIFIED(&ip4->addr))
> +	if (IN4_IS_ADDR_UNSPECIFIED(&ip4->addrs[0].addr))
>  		return 0;
>  
>  	return ifi;
> @@ -755,9 +762,9 @@ static unsigned int conf_ip4(unsigned int ifi, struct ip4_ctx *ip4)
>   */
>  static void conf_ip4_local(struct ip4_ctx *ip4)
>  {
> -	ip4->addr_seen = ip4->addr = IP4_LL_GUEST_ADDR;
> +	ip4->addr_seen = ip4->addrs[0].addr = IP4_LL_GUEST_ADDR;
>  	ip4->our_tap_addr = ip4->guest_gw = IP4_LL_GUEST_GW;
> -	ip4->prefix_len = IP4_LL_PREFIX_LEN;
> +	ip4->addrs[0].prefix_len = IP4_LL_PREFIX_LEN;
>  
>  	ip4->no_copy_addrs = ip4->no_copy_routes = true;
>  }
> @@ -766,10 +773,12 @@ static void conf_ip4_local(struct ip4_ctx *ip4)
>   * 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)
> + * @permanent:	Mark discovered addresses as permanent
>   *
>   * Return: interface index for IPv6, or 0 on failure.
>   */
> -static unsigned int conf_ip6(unsigned int ifi, struct ip6_ctx *ip6)
> +static unsigned int conf_ip6(unsigned int ifi, struct ip6_ctx *ip6,
> +			     bool permanent)
>  {
>  	int prefix_len = 0;
>  	int rc;
> @@ -792,19 +801,25 @@ static unsigned int conf_ip6(unsigned int ifi, struct ip6_ctx *ip6)
>  	}
>  
>  	rc = nl_addr_get(nl_sock, ifi, AF_INET6,
> -			 IN6_IS_ADDR_UNSPECIFIED(&ip6->addr) ? &ip6->addr : NULL,
> +			 ip6->addr_count ? NULL : &ip6->addrs[0].addr,
>  			 &prefix_len, &ip6->our_tap_ll);
>  	if (rc < 0) {
>  		debug("Couldn't discover IPv6 address: %s", strerror_(-rc));
>  		return 0;
>  	}
>  
> -	ip6->addr_seen = ip6->addr;
> +	if (!ip6->addr_count) {
> +		ip6->addrs[0].prefix_len = prefix_len ? prefix_len : 64;
> +		ip6->addrs[0].permanent = permanent;
> +		ip6->addr_count = 1;
> +	}
> +
> +	ip6->addr_seen = ip6->addrs[0].addr;
>  
>  	if (IN6_IS_ADDR_LINKLOCAL(&ip6->guest_gw))
>  		ip6->our_tap_ll = ip6->guest_gw;
>  
> -	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->addr) ||
> +	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->addrs[0].addr) ||
>  	    IN6_IS_ADDR_UNSPECIFIED(&ip6->our_tap_ll))
>  		return 0;
>  
> @@ -1149,11 +1164,13 @@ static void conf_print(const struct ctx *c)
>  		if (!c->no_dhcp) {
>  			uint32_t mask;
>  
> -			mask = htonl(0xffffffff << (32 - c->ip4.prefix_len));
> +			mask = htonl(0xffffffff <<
> +				     (32 - c->ip4.addrs[0].prefix_len));
>  
>  			info("DHCP:");
>  			info("    assign: %s",
> -			     inet_ntop(AF_INET, &c->ip4.addr, buf4, sizeof(buf4)));
> +			     inet_ntop(AF_INET, &c->ip4.addrs[0].addr,
> +				       buf4, sizeof(buf4)));
>  			info("    mask: %s",
>  			     inet_ntop(AF_INET, &mask,        buf4, sizeof(buf4)));
>  			info("    router: %s",
> @@ -1191,7 +1208,8 @@ static void conf_print(const struct ctx *c)
>  			goto dns6;
>  
>  		info("    assign: %s",
> -		     inet_ntop(AF_INET6, &c->ip6.addr, buf6, sizeof(buf6)));
> +		     inet_ntop(AF_INET6, &c->ip6.addrs[0].addr,
> +			       buf6, sizeof(buf6)));
>  		info("    router: %s",
>  		     inet_ntop(AF_INET6, &c->ip6.guest_gw, buf6, sizeof(buf6)));
>  		info("    our link-local: %s",
> @@ -1812,22 +1830,23 @@ void conf(struct ctx *c, int argc, char **argv)
>  			break;
>  		}
>  		case 'a':
> -			if (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)) {
> +			if (inet_pton(AF_INET6, optarg,
> +				      &c->ip6.addrs[0].addr) &&
> +			    !IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addrs[0].addr) &&
> +			    !IN6_IS_ADDR_LOOPBACK(&c->ip6.addrs[0].addr) &&
> +			    !IN6_IS_ADDR_V4MAPPED(&c->ip6.addrs[0].addr) &&
> +			    !IN6_IS_ADDR_V4COMPAT(&c->ip6.addrs[0].addr) &&
> +			    !IN6_IS_ADDR_MULTICAST(&c->ip6.addrs[0].addr)) {
>  				if (c->mode == MODE_PASTA)
>  					c->ip6.no_copy_addrs = true;
>  				break;
>  			}
>  
> -			if (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)) {
> +			if (inet_pton(AF_INET, optarg, &c->ip4.addrs[0].addr) &&
> +			    !IN4_IS_ADDR_UNSPECIFIED(&c->ip4.addrs[0].addr) &&
> +			    !IN4_IS_ADDR_BROADCAST(&c->ip4.addrs[0].addr) &&
> +			    !IN4_IS_ADDR_LOOPBACK(&c->ip4.addrs[0].addr) &&
> +			    !IN4_IS_ADDR_MULTICAST(&c->ip4.addrs[0].addr)) {
>  				if (c->mode == MODE_PASTA)
>  					c->ip4.no_copy_addrs = true;
>  				break;
> @@ -1836,8 +1855,8 @@ void conf(struct ctx *c, int argc, char **argv)
>  			die("Invalid address: %s", optarg);
>  			break;
>  		case 'n':
> -			c->ip4.prefix_len = conf_ip4_prefix(optarg);
> -			if (c->ip4.prefix_len < 0)
> +			c->ip4.addrs[0].prefix_len = conf_ip4_prefix(optarg);
> +			if (c->ip4.addrs[0].prefix_len < 0)
>  				die("Invalid netmask: %s", optarg);
>  
>  			break;
> @@ -1984,9 +2003,9 @@ void conf(struct ctx *c, int argc, char **argv)
>  
>  	nl_sock_init(c, false);
>  	if (!v6_only)
> -		c->ifi4 = conf_ip4(ifi4, &c->ip4);
> +		c->ifi4 = conf_ip4(ifi4, &c->ip4, c->pasta_conf_ns);
>  	if (!v4_only)
> -		c->ifi6 = conf_ip6(ifi6, &c->ip6);
> +		c->ifi6 = conf_ip6(ifi6, &c->ip6, c->pasta_conf_ns);
>  
>  	if (c->ifi4 && c->mtu < IPV4_MIN_MTU) {
>  		warn("MTU %"PRIu16" is too small for IPv4 (minimum %u)",
> @@ -2125,7 +2144,7 @@ void conf(struct ctx *c, int argc, char **argv)
>  	if (!c->ifi6) {
>  		c->no_ndp = 1;
>  		c->no_dhcpv6 = 1;
> -	} else if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr)) {
> +	} else if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addrs[0].addr)) {
>  		c->no_dhcpv6 = 1;
>  	}
>  
> diff --git a/dhcp.c b/dhcp.c
> index 6b9c2e3..46ef8e3 100644
> --- a/dhcp.c
> +++ b/dhcp.c
> @@ -352,7 +352,7 @@ int dhcp(const struct ctx *c, struct iov_tail *data)
>  	reply.secs		= 0;
>  	reply.flags		= m->flags;
>  	reply.ciaddr		= m->ciaddr;
> -	reply.yiaddr		= c->ip4.addr;
> +	reply.yiaddr		= c->ip4.addrs[0].addr;
>  	reply.siaddr		= 0;
>  	reply.giaddr		= m->giaddr;
>  	memcpy(&reply.chaddr,	m->chaddr,	sizeof(reply.chaddr));
> @@ -404,7 +404,7 @@ int dhcp(const struct ctx *c, struct iov_tail *data)
>  
>  	info("    from %s", eth_ntop(m->chaddr, macstr, sizeof(macstr)));
>  
> -	mask.s_addr = htonl(0xffffffff << (32 - c->ip4.prefix_len));
> +	mask.s_addr = htonl(0xffffffff << (32 - c->ip4.addrs[0].prefix_len));
>  	memcpy(opts[1].s,  &mask,                sizeof(mask));
>  	memcpy(opts[3].s,  &c->ip4.guest_gw,     sizeof(c->ip4.guest_gw));
>  	memcpy(opts[54].s, &c->ip4.our_tap_addr, sizeof(c->ip4.our_tap_addr));
> @@ -412,7 +412,7 @@ int dhcp(const struct ctx *c, struct iov_tail *data)
>  	/* If the gateway is not on the assigned subnet, send an option 121
>  	 * (Classless Static Routing) adding a dummy route to it.
>  	 */
> -	if ((c->ip4.addr.s_addr & mask.s_addr)
> +	if ((c->ip4.addrs[0].addr.s_addr & mask.s_addr)
>  	    != (c->ip4.guest_gw.s_addr & mask.s_addr)) {
>  		/* a.b.c.d/32:0.0.0.0, 0:a.b.c.d */
>  		opts[121].slen = 14;
> @@ -469,7 +469,7 @@ int dhcp(const struct ctx *c, struct iov_tail *data)
>  	if (m->flags & FLAG_BROADCAST)
>  		dst = in4addr_broadcast;
>  	else
> -		dst = c->ip4.addr;
> +		dst = c->ip4.addrs[0].addr;
>  
>  	tap_udp4_send(c, c->ip4.our_tap_addr, 67, dst, 68, &reply, dlen);
>  
> diff --git a/dhcpv6.c b/dhcpv6.c
> index e4df0db..7eae6a1 100644
> --- a/dhcpv6.c
> +++ b/dhcpv6.c
> @@ -625,7 +625,7 @@ int dhcpv6(struct ctx *c, struct iov_tail *data,
>  		if (mh->type == TYPE_CONFIRM && server_id)
>  			return -1;
>  
> -		if (dhcpv6_ia_notonlink(data, &c->ip6.addr)) {
> +		if (dhcpv6_ia_notonlink(data, &c->ip6.addrs[0].addr)) {
>  
>  			dhcpv6_send_ia_notonlink(c, data, &client_id_base,
>  						 ntohs(client_id->l), mh->xid);
> @@ -679,7 +679,7 @@ int dhcpv6(struct ctx *c, struct iov_tail *data,
>  
>  	tap_udp6_send(c, src, 547, tap_ip6_daddr(c, src), 546,
>  		      mh->xid, &resp, n);
> -	c->ip6.addr_seen = c->ip6.addr;
> +	c->ip6.addr_seen = c->ip6.addrs[0].addr;
>  
>  	return 1;
>  }
> @@ -703,5 +703,5 @@ void dhcpv6_init(const struct ctx *c)
>  	memcpy(resp_not_on_link.server_id.duid_lladdr,
>  	       c->our_tap_mac, sizeof(c->our_tap_mac));
>  
> -	resp.ia_addr.addr	= c->ip6.addr;
> +	resp.ia_addr.addr	= c->ip6.addrs[0].addr;
>  }
> diff --git a/fwd.c b/fwd.c
> index 44a0e10..408af30 100644
> --- a/fwd.c
> +++ b/fwd.c
> @@ -516,7 +516,7 @@ static bool fwd_guest_accessible4(const struct ctx *c,
>  	/* For IPv4, addr_seen is initialised to addr, so is always a valid
>  	 * address
>  	 */
> -	if (IN4_ARE_ADDR_EQUAL(addr, &c->ip4.addr) ||
> +	if (IN4_ARE_ADDR_EQUAL(addr, &c->ip4.addrs[0].addr) ||
>  	    IN4_ARE_ADDR_EQUAL(addr, &c->ip4.addr_seen))
>  		return false;
>  
> @@ -537,7 +537,7 @@ static bool fwd_guest_accessible6(const struct ctx *c,
>  	if (IN6_IS_ADDR_LOOPBACK(addr))
>  		return false;
>  
> -	if (IN6_ARE_ADDR_EQUAL(addr, &c->ip6.addr))
> +	if (IN6_ARE_ADDR_EQUAL(addr, &c->ip6.addrs[0].addr))
>  		return false;
>  
>  	/* For IPv6, addr_seen starts unspecified, because we don't know what LL
> @@ -587,9 +587,9 @@ static void nat_outbound(const struct ctx *c, const union inany_addr *addr,
>  	else if (inany_equals6(addr, &c->ip6.map_host_loopback))
>  		*translated = inany_loopback6;
>  	else if (inany_equals4(addr, &c->ip4.map_guest_addr))
> -		*translated = inany_from_v4(c->ip4.addr);
> +		*translated = inany_from_v4(c->ip4.addrs[0].addr);
>  	else if (inany_equals6(addr, &c->ip6.map_guest_addr))
> -		translated->a6 = c->ip6.addr;
> +		translated->a6 = c->ip6.addrs[0].addr;
>  	else
>  		*translated = *addr;
>  }
> @@ -710,10 +710,10 @@ bool nat_inbound(const struct ctx *c, const union inany_addr *addr,
>  		   inany_equals6(addr, &in6addr_loopback)) {
>  		translated->a6 = c->ip6.map_host_loopback;
>  	} else if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.map_guest_addr) &&
> -		   inany_equals4(addr, &c->ip4.addr)) {
> +		   inany_equals4(addr, &c->ip4.addrs[0].addr)) {
>  		*translated = inany_from_v4(c->ip4.map_guest_addr);
>  	} else if (!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.map_guest_addr) &&
> -		   inany_equals6(addr, &c->ip6.addr)) {
> +		   inany_equals6(addr, &c->ip6.addrs[0].addr)) {
>  		translated->a6 = c->ip6.map_guest_addr;
>  	} else if (fwd_guest_accessible(c, addr)) {
>  		*translated = *addr;
> diff --git a/ip.h b/ip.h
> index 5830b92..748cb1f 100644
> --- a/ip.h
> +++ b/ip.h
> @@ -135,4 +135,30 @@ static const struct in_addr in4addr_broadcast = { 0xffffffff };
>  #define IPV6_MIN_MTU		1280
>  #endif
>  
> +/* Maximum number of addresses per address family */
> +#define IP4_MAX_ADDRS		8
> +#define IP6_MAX_ADDRS		16
> +
> +/**
> + * struct ip4_addr_entry - IPv4 address with prefix length
> + * @addr:		IPv4 address
> + * @prefix_len:		Prefix length (netmask bits)
> + */
> +struct ip4_addr_entry {
> +	struct in_addr addr;
> +	int prefix_len;
> +	int permanent;

Might as well make these uint8_t and bool, respectively.  There will
be some padding, but the overall structure will still be smaller.

Or, it might be worth considering replacing 'permanent' with a flags
mask, in case we have future uses for it.

> +};
> +
> +/**
> + * struct ip6_addr_entry - IPv6 address with prefix length
> + * @addr:		IPv6 address
> + * @prefix_len:		Prefix length
> + */
> +struct ip6_addr_entry {
> +	struct in6_addr addr;
> +	int prefix_len;
> +	int permanent;

Ditto.

> +};
> +
>  #endif /* IP_H */
> diff --git a/ndp.c b/ndp.c
> index eb9e313..868a234 100644
> --- a/ndp.c
> +++ b/ndp.c
> @@ -257,7 +257,7 @@ static void ndp_ra(const struct ctx *c, const struct in6_addr *dst)
>  			.valid_lifetime		= ~0U,
>  			.pref_lifetime		= ~0U,
>  		},
> -		.prefix = c->ip6.addr,
> +		.prefix = c->ip6.addrs[0].addr,
>  		.source_ll = {
>  			.header = {
>  				.type		= OPT_SRC_L2_ADDR,
> @@ -466,8 +466,8 @@ void ndp_send_init_req(const struct ctx *c)
>  			.icmp6_solicited	= 0, /* Reserved */
>  			.icmp6_override		= 0, /* Reserved */
>  		},
> -		.target_addr = c->ip6.addr
> +		.target_addr = c->ip6.addrs[0].addr
>  	};
>  	debug("Sending initial NDP NS request for guest MAC address");
> -	ndp_send(c, &c->ip6.addr, &ns, sizeof(ns));
> +	ndp_send(c, &c->ip6.addrs[0].addr, &ns, sizeof(ns));
>  }
> diff --git a/passt.h b/passt.h
> index 79d01dd..533f2cb 100644
> --- a/passt.h
> +++ b/passt.h
> @@ -66,9 +66,9 @@ enum passt_modes {
>  
>  /**
>   * struct ip4_ctx - IPv4 execution context
> - * @addr:		IPv4 address assigned to guest
> + * @addrs:		IPv4 addresses assigned to guest
> + * @addr_count:		Number of addresses in addrs[] array
>   * @addr_seen:		Latest IPv4 address seen as source from tap
> - * @prefixlen:		IPv4 prefix length (netmask)
>   * @guest_gw:		IPv4 gateway as seen by the guest
>   * @map_host_loopback:	Outbound connections to this address are NATted to the
>   *                      host's 127.0.0.1
> @@ -85,9 +85,10 @@ enum passt_modes {
>   */
>  struct ip4_ctx {
>  	/* PIF_TAP addresses */
> -	struct in_addr addr;
> +	struct ip4_addr_entry addrs[IP4_MAX_ADDRS];
> +	int addr_count;
> +
>  	struct in_addr addr_seen;
> -	int prefix_len;
>  	struct in_addr guest_gw;
>  	struct in_addr map_host_loopback;
>  	struct in_addr map_guest_addr;
> @@ -107,7 +108,8 @@ struct ip4_ctx {
>  
>  /**
>   * struct ip6_ctx - IPv6 execution context
> - * @addr:		IPv6 address assigned to guest
> + * @addrs:		IPv6 addresses assigned to guest
> + * @addr_count:		Number of addresses in addrs[] array
>   * @addr_seen:		Latest IPv6 global/site address seen as source from tap
>   * @addr_ll_seen:	Latest IPv6 link-local address seen as source from tap
>   * @guest_gw:		IPv6 gateway as seen by the guest
> @@ -126,7 +128,9 @@ struct ip4_ctx {
>   */
>  struct ip6_ctx {
>  	/* PIF_TAP addresses */
> -	struct in6_addr addr;
> +	struct ip6_addr_entry addrs[IP6_MAX_ADDRS];
> +	int addr_count;
> +
>  	struct in6_addr addr_seen;
>  	struct in6_addr addr_ll_seen;
>  	struct in6_addr guest_gw;
> diff --git a/pasta.c b/pasta.c
> index 674b554..49b393c 100644
> --- a/pasta.c
> +++ b/pasta.c
> @@ -331,8 +331,8 @@ void pasta_ns_conf(struct ctx *c)
>  			if (c->ip4.no_copy_addrs) {
>  				rc = nl_addr_set(nl_sock_ns, c->pasta_ifi,
>  						 AF_INET,
> -						 &c->ip4.addr,
> -						 c->ip4.prefix_len);
> +						 &c->ip4.addrs[0].addr,
> +						 c->ip4.addrs[0].prefix_len);
>  			} else {
>  				rc = nl_addr_dup(nl_sock, c->ifi4,
>  						 nl_sock_ns, c->pasta_ifi,
> @@ -378,10 +378,12 @@ void pasta_ns_conf(struct ctx *c)
>  					  0, IFF_NOARP);
>  
>  			if (c->ip6.no_copy_addrs) {
> -				if (!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr)) {
> +				struct in6_addr *a = &c->ip6.addrs[0].addr;
> +
> +				if (!IN6_IS_ADDR_UNSPECIFIED(a)) {
>  					rc = nl_addr_set(nl_sock_ns,
> -							 c->pasta_ifi, AF_INET6,
> -							 &c->ip6.addr, 64);
> +							 c->pasta_ifi,
> +							 AF_INET6, a, 64);
>  				}
>  			} else {
>  				rc = nl_addr_dup(nl_sock, c->ifi6,
> diff --git a/tap.c b/tap.c
> index e3ea61c..0b96cc1 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -951,8 +951,8 @@ resume:
>  				c->ip6.addr_seen = *saddr;
>  			}
>  
> -			if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addr))
> -				c->ip6.addr = *saddr;
> +			if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.addrs[0].addr))
> +				c->ip6.addrs[0].addr = *saddr;
>  		} else if (!IN6_IS_ADDR_UNSPECIFIED(saddr)){
>  			c->ip6.addr_seen = *saddr;
>  		}
> diff --git a/util.h b/util.h
> index f7a941f..4273e0d 100644
> --- a/util.h
> +++ b/util.h
> @@ -401,4 +401,5 @@ static inline int wrap_getsockname(int sockfd, struct sockaddr *addr,
>  #define PASST_MAXDNAME 254 /* 253 (RFC 1035) + 1 (the terminator) */
>  void encode_domain_name(char *buf, const char *domain_name);
>  
> +
>  #endif /* UTIL_H */
> -- 
> 2.51.1
> 

-- 
David Gibson (he or they)	| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you, not the other way
				| around.
http://www.ozlabs.org/~dgibson