From: David Gibson <david@gibson.dropbear.id.au>
To: passt-dev@passt.top, Stefano Brivio <sbrivio@redhat.com>
Cc: Paul Holzinger <pholzing@redhat.com>,
David Gibson <david@gibson.dropbear.id.au>
Subject: [PATCH v2 05/23] conf: Use array indices rather than pointers for DNS array slots
Date: Wed, 21 Aug 2024 14:20:01 +1000 [thread overview]
Message-ID: <20240821042020.718422-6-david@gibson.dropbear.id.au> (raw)
In-Reply-To: <20240821042020.718422-1-david@gibson.dropbear.id.au>
Currently add_dns[46]() take a somewhat awkward double pointer to the
entry in the c->ip[46].dns array to update. It turns out to be easier to
work with indices into that array instead.
This diff does add some lines, but it's comments, and will allow some
future code reductions.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
conf.c | 73 +++++++++++++++++++++++++++++++++-------------------------
1 file changed, 41 insertions(+), 32 deletions(-)
diff --git a/conf.c b/conf.c
index 9b05afeb..2a52bc32 100644
--- a/conf.c
+++ b/conf.c
@@ -354,54 +354,65 @@ bind_all_fail:
* 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
+ * @idx: Index of free entry in array of IPv4 resolvers
+ *
+ * Return: Number of entries added (0 or 1)
*/
-static void add_dns4(struct ctx *c, const struct in_addr *addr,
- struct in_addr **conf)
+static unsigned add_dns4(struct ctx *c, const struct in_addr *addr,
+ unsigned idx)
{
+ unsigned added = 0;
+
/* 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)++;
+ c->ip4.dns[idx] = c->ip4.gw;
+ added++;
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
c->ip4.dns_match = c->ip4.gw;
}
} else {
- **conf = *addr;
- (*conf)++;
+ c->ip4.dns[idx] = *addr;
+ added++;
}
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
c->ip4.dns_host = *addr;
+
+ return added;
}
/**
* 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
+ * @idx: Index of free entry in array of IPv6 resolvers
+ *
+ * Return: Number of entries added (0 or 1)
*/
-static void add_dns6(struct ctx *c,
- struct in6_addr *addr, struct in6_addr **conf)
+static unsigned add_dns6(struct ctx *c, struct in6_addr *addr, unsigned idx)
{
+ unsigned added = 0;
+
/* Guest or container can only access local addresses via redirect */
if (IN6_IS_ADDR_LOOPBACK(addr)) {
if (!c->no_map_gw) {
- **conf = c->ip6.gw;
- (*conf)++;
+ c->ip6.dns[idx] = c->ip6.gw;
+ added++;
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
c->ip6.dns_match = *addr;
}
} else {
- **conf = *addr;
- (*conf)++;
+ c->ip6.dns[idx] = *addr;
+ added++;
}
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
c->ip6.dns_host = *addr;
+
+ return added;
}
/**
@@ -410,18 +421,19 @@ static void add_dns6(struct ctx *c,
*/
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;
+ unsigned dns4_idx = 0, dns6_idx = 0;
struct fqdn *s = c->dns_search;
struct lineread resolvconf;
+ struct in6_addr dns6_tmp;
+ struct in_addr dns4_tmp;
unsigned int added = 0;
ssize_t line_len;
char *line, *end;
const char *p;
- dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(dns4);
- dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(dns6);
+ dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns[0]);
+ dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns[0]);
dnss_set = !!*s->n || c->no_dns_search;
dns_set = (dns4_set && dns6_set) || c->no_dns;
@@ -442,17 +454,15 @@ static void get_dns(struct ctx *c)
if (end)
*end = 0;
- if (!dns4_set &&
- dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) - 1
+ if (!dns4_set && dns4_idx < ARRAY_SIZE(c->ip4.dns) - 1
&& inet_pton(AF_INET, p + 1, &dns4_tmp)) {
- add_dns4(c, &dns4_tmp, &dns4);
+ dns4_idx += add_dns4(c, &dns4_tmp, dns4_idx);
added++;
}
- if (!dns6_set &&
- dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) - 1
+ if (!dns6_set && dns6_idx < ARRAY_SIZE(c->ip6.dns) - 1
&& inet_pton(AF_INET6, p + 1, &dns6_tmp)) {
- add_dns6(c, &dns6_tmp, &dns6);
+ dns6_idx += add_dns6(c, &dns6_tmp, dns6_idx);
added++;
}
} else if (!dnss_set && strstr(line, "search ") == line &&
@@ -1236,8 +1246,7 @@ void conf(struct ctx *c, int argc, char **argv)
bool copy_addrs_opt = false, copy_routes_opt = false;
enum fwd_ports_mode fwd_default = FWD_NONE;
bool v4_only = false, v6_only = false;
- struct in6_addr *dns6 = c->ip6.dns;
- struct in_addr *dns4 = c->ip4.dns;
+ unsigned dns4_idx = 0, dns6_idx = 0;
struct fqdn *dnss = c->dns_search;
unsigned int ifi4 = 0, ifi6 = 0;
const char *logfile = NULL;
@@ -1662,13 +1671,13 @@ void conf(struct ctx *c, int argc, char **argv)
if (!strcmp(optarg, "none")) {
c->no_dns = 1;
- dns4 = &c->ip4.dns[0];
+ dns4_idx = 0;
memset(c->ip4.dns, 0, sizeof(c->ip4.dns));
c->ip4.dns[0] = (struct in_addr){ 0 };
c->ip4.dns_match = (struct in_addr){ 0 };
c->ip4.dns_host = (struct in_addr){ 0 };
- dns6 = &c->ip6.dns[0];
+ dns6_idx = 0;
memset(c->ip6.dns, 0, sizeof(c->ip6.dns));
c->ip6.dns_match = (struct in6_addr){ 0 };
c->ip6.dns_host = (struct in6_addr){ 0 };
@@ -1678,15 +1687,15 @@ void conf(struct ctx *c, int argc, char **argv)
c->no_dns = 0;
- if (dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) &&
+ if (dns4_idx < ARRAY_SIZE(c->ip4.dns) &&
inet_pton(AF_INET, optarg, &dns4_tmp)) {
- add_dns4(c, &dns4_tmp, &dns4);
+ dns4_idx += add_dns4(c, &dns4_tmp, dns4_idx);
continue;
}
- if (dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) &&
+ if (dns6_idx < ARRAY_SIZE(c->ip6.dns) &&
inet_pton(AF_INET6, optarg, &dns6_tmp)) {
- add_dns6(c, &dns6_tmp, &dns6);
+ dns6_idx += add_dns6(c, &dns6_tmp, dns6_idx);
continue;
}
--
@@ -354,54 +354,65 @@ bind_all_fail:
* 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
+ * @idx: Index of free entry in array of IPv4 resolvers
+ *
+ * Return: Number of entries added (0 or 1)
*/
-static void add_dns4(struct ctx *c, const struct in_addr *addr,
- struct in_addr **conf)
+static unsigned add_dns4(struct ctx *c, const struct in_addr *addr,
+ unsigned idx)
{
+ unsigned added = 0;
+
/* 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)++;
+ c->ip4.dns[idx] = c->ip4.gw;
+ added++;
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match))
c->ip4.dns_match = c->ip4.gw;
}
} else {
- **conf = *addr;
- (*conf)++;
+ c->ip4.dns[idx] = *addr;
+ added++;
}
if (IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_host))
c->ip4.dns_host = *addr;
+
+ return added;
}
/**
* 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
+ * @idx: Index of free entry in array of IPv6 resolvers
+ *
+ * Return: Number of entries added (0 or 1)
*/
-static void add_dns6(struct ctx *c,
- struct in6_addr *addr, struct in6_addr **conf)
+static unsigned add_dns6(struct ctx *c, struct in6_addr *addr, unsigned idx)
{
+ unsigned added = 0;
+
/* Guest or container can only access local addresses via redirect */
if (IN6_IS_ADDR_LOOPBACK(addr)) {
if (!c->no_map_gw) {
- **conf = c->ip6.gw;
- (*conf)++;
+ c->ip6.dns[idx] = c->ip6.gw;
+ added++;
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match))
c->ip6.dns_match = *addr;
}
} else {
- **conf = *addr;
- (*conf)++;
+ c->ip6.dns[idx] = *addr;
+ added++;
}
if (IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_host))
c->ip6.dns_host = *addr;
+
+ return added;
}
/**
@@ -410,18 +421,19 @@ static void add_dns6(struct ctx *c,
*/
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;
+ unsigned dns4_idx = 0, dns6_idx = 0;
struct fqdn *s = c->dns_search;
struct lineread resolvconf;
+ struct in6_addr dns6_tmp;
+ struct in_addr dns4_tmp;
unsigned int added = 0;
ssize_t line_len;
char *line, *end;
const char *p;
- dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(dns4);
- dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(dns6);
+ dns4_set = !c->ifi4 || !IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns[0]);
+ dns6_set = !c->ifi6 || !IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns[0]);
dnss_set = !!*s->n || c->no_dns_search;
dns_set = (dns4_set && dns6_set) || c->no_dns;
@@ -442,17 +454,15 @@ static void get_dns(struct ctx *c)
if (end)
*end = 0;
- if (!dns4_set &&
- dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) - 1
+ if (!dns4_set && dns4_idx < ARRAY_SIZE(c->ip4.dns) - 1
&& inet_pton(AF_INET, p + 1, &dns4_tmp)) {
- add_dns4(c, &dns4_tmp, &dns4);
+ dns4_idx += add_dns4(c, &dns4_tmp, dns4_idx);
added++;
}
- if (!dns6_set &&
- dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) - 1
+ if (!dns6_set && dns6_idx < ARRAY_SIZE(c->ip6.dns) - 1
&& inet_pton(AF_INET6, p + 1, &dns6_tmp)) {
- add_dns6(c, &dns6_tmp, &dns6);
+ dns6_idx += add_dns6(c, &dns6_tmp, dns6_idx);
added++;
}
} else if (!dnss_set && strstr(line, "search ") == line &&
@@ -1236,8 +1246,7 @@ void conf(struct ctx *c, int argc, char **argv)
bool copy_addrs_opt = false, copy_routes_opt = false;
enum fwd_ports_mode fwd_default = FWD_NONE;
bool v4_only = false, v6_only = false;
- struct in6_addr *dns6 = c->ip6.dns;
- struct in_addr *dns4 = c->ip4.dns;
+ unsigned dns4_idx = 0, dns6_idx = 0;
struct fqdn *dnss = c->dns_search;
unsigned int ifi4 = 0, ifi6 = 0;
const char *logfile = NULL;
@@ -1662,13 +1671,13 @@ void conf(struct ctx *c, int argc, char **argv)
if (!strcmp(optarg, "none")) {
c->no_dns = 1;
- dns4 = &c->ip4.dns[0];
+ dns4_idx = 0;
memset(c->ip4.dns, 0, sizeof(c->ip4.dns));
c->ip4.dns[0] = (struct in_addr){ 0 };
c->ip4.dns_match = (struct in_addr){ 0 };
c->ip4.dns_host = (struct in_addr){ 0 };
- dns6 = &c->ip6.dns[0];
+ dns6_idx = 0;
memset(c->ip6.dns, 0, sizeof(c->ip6.dns));
c->ip6.dns_match = (struct in6_addr){ 0 };
c->ip6.dns_host = (struct in6_addr){ 0 };
@@ -1678,15 +1687,15 @@ void conf(struct ctx *c, int argc, char **argv)
c->no_dns = 0;
- if (dns4 - &c->ip4.dns[0] < ARRAY_SIZE(c->ip4.dns) &&
+ if (dns4_idx < ARRAY_SIZE(c->ip4.dns) &&
inet_pton(AF_INET, optarg, &dns4_tmp)) {
- add_dns4(c, &dns4_tmp, &dns4);
+ dns4_idx += add_dns4(c, &dns4_tmp, dns4_idx);
continue;
}
- if (dns6 - &c->ip6.dns[0] < ARRAY_SIZE(c->ip6.dns) &&
+ if (dns6_idx < ARRAY_SIZE(c->ip6.dns) &&
inet_pton(AF_INET6, optarg, &dns6_tmp)) {
- add_dns6(c, &dns6_tmp, &dns6);
+ dns6_idx += add_dns6(c, &dns6_tmp, dns6_idx);
continue;
}
--
2.46.0
next prev parent reply other threads:[~2024-08-21 4:20 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-08-21 4:19 [PATCH v2 00/23] Allow configuration of special case NATs David Gibson
2024-08-21 4:19 ` [PATCH v2 01/23] treewide: Use "our address" instead of "forwarding address" David Gibson
2024-08-21 4:19 ` [PATCH v2 02/23] util: Helper for formatting MAC addresses David Gibson
2024-08-21 4:19 ` [PATCH v2 03/23] treewide: Rename MAC address fields for clarity David Gibson
2024-08-21 4:20 ` [PATCH v2 04/23] treewide: Use struct assignment instead of memcpy() for IP addresses David Gibson
2024-08-21 4:20 ` David Gibson [this message]
2024-08-21 4:20 ` [PATCH v2 06/23] conf: More accurately count entries added in get_dns() David Gibson
2024-08-21 4:20 ` [PATCH v2 07/23] conf: Move DNS array bounds checks into add_dns[46] David Gibson
2024-08-21 4:20 ` [PATCH v2 08/23] conf: Move adding of a nameserver from resolv.conf into subfunction David Gibson
2024-08-21 4:20 ` [PATCH v2 09/23] conf: Correct setting of dns_match address in add_dns6() David Gibson
2024-08-21 4:20 ` [PATCH v2 10/23] conf: Treat --dns addresses as guest visible addresses David Gibson
2024-08-21 4:20 ` [PATCH v2 11/23] conf: Remove incorrect initialisation of addr_ll_seen David Gibson
2024-08-21 4:20 ` [PATCH v2 12/23] util: Correct sock_l4() binding for link local addresses David Gibson
2024-08-21 4:20 ` [PATCH v2 13/23] treewide: Change misleading 'addr_ll' name David Gibson
2024-08-21 4:20 ` [PATCH v2 14/23] Clarify which addresses in ip[46]_ctx are meaningful where David Gibson
2024-08-21 4:20 ` [PATCH v2 15/23] Initialise our_tap_ll to ip6.gw when suitable David Gibson
2024-08-21 4:20 ` [PATCH v2 16/23] fwd: Helpers to clarify what host addresses aren't guest accessible David Gibson
2024-08-21 4:20 ` [PATCH v2 17/23] fwd: Split notion of "our tap address" from gateway for IPv4 David Gibson
2024-08-21 4:20 ` [PATCH v2 18/23] Don't take "our" MAC address from the host David Gibson
2024-08-21 4:20 ` [PATCH v2 19/23] conf, fwd: Split notion of gateway/router from guest-visible host address David Gibson
2024-08-21 4:20 ` [PATCH v2 20/23] test: Reconfigure IPv6 address after changing MTU David Gibson
2024-08-21 4:20 ` [PATCH v2 21/23] conf: Allow address remapped to host to be configured David Gibson
2024-08-21 4:20 ` [PATCH v2 22/23] fwd: Distinguish translatable from untranslatable addresses on inbound David Gibson
2024-08-21 4:20 ` [PATCH v2 23/23] fwd, conf: Allow NAT of the guest's assigned address David Gibson
2024-08-21 10:38 ` [PATCH v2 00/23] Allow configuration of special case NATs Stefano Brivio
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