On 2026-04-21 02:25, David Gibson wrote:
Implement serialisation of our current forwarding rules in conf.c, deserialising it to display in the pesto client. Doing this requires adding ip.c, inany.c, bitmap.c, lineread.c and fwd_rule.c to the pesto build. With previous preparations that now requires only a trivial change [...]
+ + +/** + * fwd_rule_read() - Read serialised rule from an fd + * @fd: fd to serialise to + * @rule: Buffer to store rule into + * + * Return: 0 on success, -1 on error (with errno set) + */ +int fwd_rule_read(int fd, struct fwd_rule *rule) +{ + if (read_all_buf(fd, rule, sizeof(*rule))) + return -1; + + /* Byteswap for host */ + rule->first = ntohs(rule->first); + rule->last = ntohs(rule->last); + rule->to = htons(rule->to); Or ntohs() ?
/jon
+ + return 0; +} + +/** + * fwd_rule_write() - Serialise rule to an fd + * @fd: fd to serialise to + * @rule: Rule to send + * + * Return: 0 on success, -1 on error (with errno set) + */ +int fwd_rule_write(int fd, const struct fwd_rule *rule) +{ + struct fwd_rule tmp = *rule; + + /* Byteswap for transport */ + tmp.first = htons(tmp.first); + tmp.last = htons(tmp.last); + tmp.to = htons(tmp.to); + + return write_all_buf(fd, &tmp, sizeof(tmp)); +} diff --git a/fwd_rule.h b/fwd_rule.h index f51f1b4b..330d49eb 100644 --- a/fwd_rule.h +++ b/fwd_rule.h @@ -29,6 +29,8 @@ #define FWD_CAP_UDP BIT(3) #define FWD_CAP_SCAN BIT(4) #define FWD_CAP_IFNAME BIT(5) +#define FWD_CAP_ALL (FWD_CAP_IPV4 | FWD_CAP_IPV6 | FWD_CAP_TCP | \ + FWD_CAP_UDP | FWD_CAP_SCAN | FWD_CAP_IFNAME)
/** * struct fwd_rule - Forwarding rule governing a range of ports @@ -99,6 +101,8 @@ void fwd_probe_ephemeral(void); const union inany_addr *fwd_rule_addr(const struct fwd_rule *rule); const char *fwd_rule_fmt(const struct fwd_rule *rule, char *dst, size_t size); void fwd_rule_parse(char optname, const char *optarg, struct fwd_table *fwd); +int fwd_rule_read(int fd, struct fwd_rule *rule); +int fwd_rule_write(int fd, const struct fwd_rule *rule);
/** * fwd_rules_dump() - Dump forwarding rules diff --git a/lineread.c b/lineread.c index b9ceae10..a4269a66 100644 --- a/lineread.c +++ b/lineread.c @@ -19,8 +19,8 @@ #include
#include +#include "common.h" #include "lineread.h" -#include "util.h"
/** * lineread_init() - Prepare for line by line file reading without allocation diff --git a/pesto.c b/pesto.c index 3e34bbac..35a4d559 100644 --- a/pesto.c +++ b/pesto.c @@ -34,6 +34,7 @@ #include "common.h" #include "seccomp_pesto.h" #include "serialise.h" +#include "fwd_rule.h" #include "pesto.h" #include "log.h"
@@ -66,6 +67,7 @@ static void usage(const char *name, FILE *f, int status) struct pif_configuration { uint8_t pif; char name[PIF_NAME_SIZE]; + struct fwd_table fwd; };
struct configuration { @@ -123,6 +125,7 @@ static bool read_pif_conf(int fd, struct configuration *conf) struct pif_configuration *pc; struct pesto_pif_info info; uint8_t pif; + unsigned i;
if (read_u8(fd, &pif) < 0) die("Error reading from control socket"); @@ -149,8 +152,17 @@ static bool read_pif_conf(int fd, struct configuration *conf) static_assert(sizeof(info.name) == sizeof(pc->name), "Mismatching pif name lengths"); memcpy(pc->name, info.name, sizeof(pc->name)); - - debug("PIF %"PRIu8": %s", pc->pif, pc->name); + pc->fwd.caps = ntohl(info.caps); + pc->fwd.count = ntohl(info.count); + + debug("PIF %"PRIu8": %s, %"PRIu32" rules, capabilities 0x%"PRIx32 + ":%s%s%s%s%s%s", pc->pif, pc->name, pc->fwd.count, pc->fwd.caps, + pc->fwd.caps & FWD_CAP_IPV4 ? " IPv4" : "", + pc->fwd.caps & FWD_CAP_IPV6 ? " IPv6" : "", + pc->fwd.caps & FWD_CAP_TCP ? " TCP" : "", + pc->fwd.caps & FWD_CAP_UDP ? " UDP" : "", + pc->fwd.caps & FWD_CAP_SCAN ? " scan" : "", + pc->fwd.caps & FWD_CAP_IFNAME ? " ifname" : "");
/* O(n^2), but n is bounded by MAX_PIFS */ if (pif_conf_by_num(conf, pc->pif)) @@ -160,6 +172,18 @@ static bool read_pif_conf(int fd, struct configuration *conf) if (pif_conf_by_name(conf, pc->name)) die("Received duplicate interface name");
+ /* NOTE: We read the fwd rules directly into fwd.rules, rather than + * using fwd_rule_add(). This means we can read and display rules even + * if something has gone wrong (in pesto or passt) and we get rules that + * fwd_rule_add() would reject. It does have the side effect that we + * never assign socket space for the fwd rules, but we don't need that + * within pesto. + */ + for (i = 0; i < pc->fwd.count; i++) { + if (fwd_rule_read(fd, &pc->fwd.rules[i]) < 0) + die("Error reading from control socket"); + } + conf->npifs++; return true; } @@ -175,7 +199,8 @@ static void show_conf(const struct configuration *conf) for (i = 0; i < conf->npifs; i++) { const struct pif_configuration *pc = &conf->pif[i]; printf(" %s\n", pc->name); - printf(" TBD\n"); + fwd_rules_dump(printf, pc->fwd.rules, pc->fwd.count, + " ", "\n"); } }
@@ -288,6 +313,12 @@ int main(int argc, char **argv) ntohl(hello.pif_name_size), PIF_NAME_SIZE); }
+ if (ntohl(hello.ifnamsiz) != IFNAMSIZ) { + die("Server has unexpected IFNAMSIZ (%" + PRIu32" not %"PRIu32"\n", + ntohl(hello.ifnamsiz), IFNAMSIZ); + } + while (read_pif_conf(s, &conf)) ;
diff --git a/pesto.h b/pesto.h index ac4c2b58..8f6bbf65 100644 --- a/pesto.h +++ b/pesto.h @@ -26,11 +26,13 @@ * @magic: PESTO_SERVER_MAGIC * @version: Version number * @pif_name_size: Server's value for PIF_NAME_SIZE + * @ifnamsiz: Server's value for IFNAMSIZ */ struct pesto_hello { char magic[8]; uint32_t version; uint32_t pif_name_size; + uint32_t ifnamsiz; } __attribute__ ((__packed__));
static_assert(sizeof(PESTO_SERVER_MAGIC) @@ -41,9 +43,13 @@ static_assert(sizeof(PESTO_SERVER_MAGIC) * struct pesto_pif_info - Message with basic metadata about a pif * @resv_: Alignment gap (must be 0) * @name: Name (\0 terminated) + * @caps: Forwarding capabilities for this pif + * @count: Number of forwarding rules for this pif */ struct pesto_pif_info { char name[PIF_NAME_SIZE]; + uint32_t caps; + uint32_t count; } __attribute__ ((__packed__));
#endif /* PESTO_H */