diff options
| -rw-r--r-- | conf.c | 172 |
1 files changed, 90 insertions, 82 deletions
@@ -490,6 +490,51 @@ out: } /** + * conf_ns_opt() - Parse non-option argument to namespace paths + * @userns: buffer of size PATH_MAX, initially contains --userns + * argument (may be empty), updated with userns path + * @netns: buffer of size PATH_MAX, updated with netns path + * @arg: PID, path or name of network namespace + * + * Return: 0 on success, negative error code otherwise + */ +static int conf_ns_opt(char *userns, char *netns, const char *arg) +{ + char *endptr; + long pidval; + int ret; + + pidval = strtol(arg, &endptr, 10); + if (!*endptr) { + /* Looks like a pid */ + if (pidval < 0 || pidval > INT_MAX) { + err("Invalid PID %s", arg); + return -EINVAL; + } + + snprintf(netns, PATH_MAX, "/proc/%ld/ns/net", pidval); + if (!*userns) + snprintf(userns, PATH_MAX, "/proc/%ld/ns/user", pidval); + return 0; + } + + 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_ns_check() - Check if we can enter configured namespaces * @arg: Execution context * @@ -508,102 +553,58 @@ static int conf_ns_check(void *arg) } /** - * conf_ns_opt() - Open network, user namespaces descriptors from configuration - * @c: Execution context - * @conf_userns: --userns argument, can be an empty string - * @optarg: PID, path or name of namespace + * conf_ns_open() - Open network, user namespaces descriptors from configuration + * @c: Execution context + * @userns: --userns argument, can be an empty string + * @netns: network namespace path * * Return: 0 on success, negative error code otherwise */ -static int conf_ns_opt(struct ctx *c, - const char *conf_userns, const char *optarg) +static int conf_ns_open(struct ctx *c, const char *userns, const char *netns) { - int ufd = -1, nfd = -1, try, ret, netns_only_reset = c->netns_only; - char userns[PATH_MAX] = { 0 }, netns[PATH_MAX]; - char *endptr; - long pid_arg; - pid_t pid; + int ufd = -1, nfd = -1; - if (c->netns_only && *conf_userns) { + if (c->netns_only && *userns) { err("Both --userns and --netns-only given"); return -EINVAL; } - /* It might be a PID, a netns path, or a netns name */ - for (try = 0; try < 3; try++) { - if (try == 0) { - pid_arg = strtol(optarg, &endptr, 10); - if (*endptr || pid_arg < 0 || pid_arg > INT_MAX) - continue; - - pid = pid_arg; - - if (!*conf_userns && !c->netns_only) { - ret = snprintf(userns, PATH_MAX, - "/proc/%i/ns/user", pid); - if (ret <= 0 || ret > (int)sizeof(userns)) - continue; - } - ret = snprintf(netns, PATH_MAX, "/proc/%i/ns/net", pid); - if (ret <= 0 || ret > (int)sizeof(netns)) - continue; - } else if (try == 1) { - if (!*conf_userns) - c->netns_only = 1; - - ret = snprintf(netns, PATH_MAX, "%s", optarg); - if (ret <= 0 || ret > (int)sizeof(userns)) - continue; - } else if (try == 2) { - ret = snprintf(netns, PATH_MAX, "%s/%s", - NETNS_RUN_DIR, optarg); - if (ret <= 0 || ret > (int)sizeof(netns)) - continue; - } - - if (!c->netns_only) { - if (*conf_userns) - ufd = open(conf_userns, O_RDONLY | O_CLOEXEC); - else if (*userns) - ufd = open(userns, O_RDONLY | O_CLOEXEC); - } - - nfd = open(netns, O_RDONLY | O_CLOEXEC); - - if (nfd == -1 || (ufd == -1 && !c->netns_only)) { - if (nfd >= 0) - close(nfd); - - if (ufd >= 0) - close(ufd); + nfd = open(netns, O_RDONLY | O_CLOEXEC); + if (nfd < 0) { + err("Couldn't open network namespace %s", netns); + return -ENOENT; + } - continue; + if (!c->netns_only && *userns) { + ufd = open(userns, O_RDONLY | O_CLOEXEC); + if (ufd < 0) { + close(nfd); + err("Couldn't open user namespace %s", userns); + return -ENOENT; } + } - c->pasta_netns_fd = nfd; - c->pasta_userns_fd = ufd; - - NS_CALL(conf_ns_check, c); + c->pasta_netns_fd = nfd; + c->pasta_userns_fd = ufd; + c->netns_only = !*userns; - if (c->pasta_netns_fd >= 0) { - char buf[PATH_MAX]; + NS_CALL(conf_ns_check, c); - if (try == 0 || c->no_netns_quit) - return 0; + if (c->pasta_netns_fd < 0) { + err("Couldn't switch to pasta namespaces"); + return -ENOENT; + } - strncpy(buf, netns, PATH_MAX); - strncpy(c->netns_base, basename(buf), PATH_MAX - 1); - strncpy(buf, netns, PATH_MAX); - strncpy(c->netns_dir, dirname(buf), PATH_MAX - 1); + if (!c->no_netns_quit) { + char buf[PATH_MAX]; - return 0; - } + strncpy(buf, netns, PATH_MAX); + strncpy(c->netns_base, basename(buf), PATH_MAX - 1); + strncpy(buf, netns, PATH_MAX); + strncpy(c->netns_dir, dirname(buf), PATH_MAX - 1); } - c->netns_only = netns_only_reset; - - err("Namespace %s not found", optarg); - return -ENOENT; + return 0; } /** @@ -1051,7 +1052,7 @@ void conf(struct ctx *c, int argc, char **argv) { 0 }, }; struct get_bound_ports_ns_arg ns_ports_arg = { .c = c }; - char userns[PATH_MAX] = { 0 }; + char userns[PATH_MAX] = { 0 }, netns[PATH_MAX] = { 0 }; enum conf_port_type tcp_tap = 0, tcp_init = 0; enum conf_port_type udp_tap = 0, udp_init = 0; bool v4_only = false, v6_only = false; @@ -1464,7 +1465,7 @@ void conf(struct ctx *c, int argc, char **argv) check_root(c); if (c->mode == MODE_PASTA && optind + 1 == argc) { - ret = conf_ns_opt(c, userns, argv[optind]); + ret = conf_ns_opt(userns, netns, argv[optind]); if (ret < 0) usage(argv[0]); } else if (c->mode == MODE_PASTA && *userns && optind == argc) { @@ -1477,8 +1478,15 @@ void conf(struct ctx *c, int argc, char **argv) if (c->pasta_conf_ns) c->no_ra = 1; - if (c->mode == MODE_PASTA && c->pasta_netns_fd == -1) - pasta_start_ns(c); + if (c->mode == MODE_PASTA) { + if (*netns) { + ret = conf_ns_open(c, userns, netns); + if (ret < 0) + usage(argv[0]); + } else { + pasta_start_ns(c); + } + } if (nl_sock_init(c)) { err("Failed to get netlink socket"); |