diff options
Diffstat (limited to 'app/tools/wg-quick.c')
| -rw-r--r-- | app/tools/wg-quick.c | 666 |
1 files changed, 0 insertions, 666 deletions
diff --git a/app/tools/wg-quick.c b/app/tools/wg-quick.c deleted file mode 100644 index 745f5ee6..00000000 --- a/app/tools/wg-quick.c +++ /dev/null @@ -1,666 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 - * - * Copyright © 2015-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. - * - * This is a shell script written in C. It very intentionally still functions like - * a shell script, calling out to external executables such as ip(8). - */ - -#define _GNU_SOURCE -#include <stdlib.h> -#include <stdio.h> -#include <stdbool.h> -#include <string.h> -#include <strings.h> -#include <stdarg.h> -#include <ctype.h> -#include <time.h> -#include <unistd.h> -#include <errno.h> -#include <regex.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <sys/wait.h> -#include <sys/param.h> - -#ifndef WG_CONFIG_SEARCH_PATHS -#define WG_CONFIG_SEARCH_PATHS "/data/misc/wireguard /data/data/com.wireguard.android/files" -#endif - -#define _printf_(x, y) __attribute__((format(printf, x, y))) -#define _cleanup_(x) __attribute__((cleanup(x))) -#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0])) - -static bool is_exiting = false; - -static void *xmalloc(size_t size) -{ - void *ret = malloc(size); - if (ret) - return ret; - perror("Error: malloc"); - exit(errno); -} - -static void *xstrdup(const char *str) -{ - char *ret = strdup(str); - if (ret) - return ret; - perror("Error: strdup"); - exit(errno); -} - -static void xregcomp(regex_t *preg, const char *regex, int cflags) -{ - if (regcomp(preg, regex, cflags)) { - fprintf(stderr, "Error: Regex compilation error\n"); - exit(EBADR); - } -} - -static char *concat(char *first, ...) -{ - va_list args; - size_t len = 0; - char *ret; - - va_start(args, first); - for (char *i = first; i; i = va_arg(args, char *)) - len += strlen(i); - va_end(args); - - ret = xmalloc(len + 1); - ret[0] = '\0'; - - va_start(args, first); - for (char *i = first; i; i = va_arg(args, char *)) - strcat(ret, i); - va_end(args); - - return ret; -} - -static char *concat_and_free(char *orig, const char *delim, const char *new_line) -{ - char *ret; - - if (!orig) - ret = xstrdup(new_line); - else - ret = concat(orig, delim, new_line, NULL); - free(orig); - return ret; -} - -struct command_buffer { - char *line; - size_t len; - FILE *stream; -}; - -static void free_command_buffer(struct command_buffer *c) -{ - if (!c) - return; - if (c->stream) - pclose(c->stream); - free(c->line); -} - -static void freep(void *p) -{ - free(*(void **)p); -} -static void fclosep(FILE **f) -{ - if (*f) - fclose(*f); -} -#define _cleanup_free_ _cleanup_(freep) -#define _cleanup_fclose_ _cleanup_(fclosep) - -#define DEFINE_CMD(name) _cleanup_(free_command_buffer) struct command_buffer name = { 0 }; - -static char *vcmd_ret(struct command_buffer *c, const char *cmd_fmt, va_list args) -{ - _cleanup_free_ char *cmd = NULL; - - if (!c->stream && !cmd_fmt) - return NULL; - if (c->stream && cmd_fmt) - pclose(c->stream); - - if (cmd_fmt) { - if (vasprintf(&cmd, cmd_fmt, args) < 0) { - perror("Error: vasprintf"); - exit(errno); - } - - c->stream = popen(cmd, "r"); - if (!c->stream) { - perror("Error: popen"); - exit(errno); - } - } - errno = 0; - if (getline(&c->line, &c->len, c->stream) < 0) { - if (errno) { - perror("Error: getline"); - exit(errno); - } - return NULL; - } - return c->line; -} - -_printf_(1, 2) static void cmd(const char *cmd_fmt, ...) -{ - _cleanup_free_ char *cmd = NULL; - va_list args; - int ret; - - va_start(args, cmd_fmt); - if (vasprintf(&cmd, cmd_fmt, args) < 0) { - perror("Error: vasprintf"); - exit(errno); - } - va_end(args); - - printf("[#] %s\n", cmd); - ret = system(cmd); - - if (ret < 0) - ret = ESRCH; - else if (ret > 0) - ret = WIFEXITED(ret) ? WEXITSTATUS(ret) : EIO; - - if (ret && !is_exiting) - exit(ret); -} - -_printf_(2, 3) static char *cmd_ret(struct command_buffer *c, const char *cmd_fmt, ...) -{ - va_list args; - char *ret; - - va_start(args, cmd_fmt); - ret = vcmd_ret(c, cmd_fmt, args); - va_end(args); - return ret; -} - -_printf_(1, 2) static void cndc(const char *cmd_fmt, ...) -{ - DEFINE_CMD(c); - int error_code; - char *ret; - va_list args; - _cleanup_free_ char *ndc_fmt = concat("ndc ", cmd_fmt, NULL); - - va_start(args, cmd_fmt); - printf("[#] "); - vprintf(ndc_fmt, args); - printf("\n"); - va_end(args); - - va_start(args, cmd_fmt); - ret = vcmd_ret(&c, ndc_fmt, args); - va_end(args); - - if (!ret) { - fprintf(stderr, "Error: could not call ndc\n"); - exit(ENOSYS); - } - - error_code = atoi(ret); - if (error_code >= 400 && error_code < 600) { - fprintf(stderr, "Error: %s\n", ret); - exit(ENONET); - } -} - -static void auto_su(int argc, char *argv[]) -{ - char *args[argc + 4]; - - if (!getuid()) - return; - - args[0] = "su"; - args[1] = "-p"; - args[2] = "-c"; - memcpy(&args[3], argv, argc * sizeof(*args)); - args[argc + 3] = NULL; - - printf("[$] su -p -c "); - for (int i = 0; i < argc; ++i) - printf("%s%c", argv[i], i == argc - 1 ? '\n' : ' '); - - execvp("su", args); - exit(errno); -} - -static void add_if(const char *iface) -{ - cmd("ip link add %s type wireguard", iface); -} - -static void del_if(const char *iface) -{ - DEFINE_CMD(c); - regex_t reg; - regmatch_t matches[2]; - char *netid = NULL; - _cleanup_free_ char *regex = concat("0xc([0-9a-f]+)/0xcffff lookup ", iface, NULL); - - xregcomp(®, regex, REG_EXTENDED); - - cmd("ip link del %s", iface); - for (char *ret = cmd_ret(&c, "ip rule show"); ret; ret = cmd_ret(&c, NULL)) { - if (!regexec(®, ret, ARRAY_SIZE(matches), matches, 0)) { - ret[matches[1].rm_eo] = '\0'; - netid = &ret[matches[1].rm_so]; - break; - } - } - - if (netid) - cndc("network destroy %lu", strtoul(netid, NULL, 16)); -} - -static void up_if(unsigned int *netid, const char *iface) -{ - srandom(time(NULL) ^ getpid()); /* Not real randomness. */ - - while (*netid < 4096) - *netid = random() & 0xfffe; - - cmd("wg set %s fwmark 0x20000", iface); - cndc("interface setcfg %s up", iface); - cndc("network create %u vpn 1 1", *netid); - cndc("network interface add %u %s", *netid, iface); - cndc("network users add %u 0-99999", *netid); -} - -static void set_dnses(unsigned int netid, const char *dnses) -{ - size_t len = strlen(dnses); - if (len > (1<<16)) - return; - _cleanup_free_ char *mutable = xstrdup(dnses); - _cleanup_free_ char *arglist = xmalloc(len * 4 + 1); - _cleanup_free_ char *arg = xmalloc(len + 4); - - if (!len) - return; - arglist[0] = '\0'; - - for (char *dns = strtok(mutable, ", \t\n"); dns; dns = strtok(NULL, ", \t\n")) { - if (strchr(dns, '\'') || strchr(dns, '\\')) - continue; - snprintf(arg, len + 3, "'%s' ", dns); - strncat(arglist, arg, len * 4 - 1); - } - if (!strlen(arglist)) - return; - cndc("resolver setnetdns %u '' %s", netid, arglist); -} - -static void add_addr(const char *iface, const char *addr) -{ - if (strchr(addr, ':')) { - cndc("interface ipv6 %s enable", iface); - cmd("ip -6 addr add '%s' dev %s", addr, iface); - } else { - _cleanup_free_ char *mut_addr = strdup(addr); - char *slash = strchr(mut_addr, '/'); - unsigned char mask = 32; - - if (slash) { - *slash = '\0'; - mask = atoi(slash + 1); - } - cndc("interface setcfg %s '%s' %u", iface, mut_addr, mask); - } -} - -static void set_addr(const char *iface, const char *addrs) -{ - _cleanup_free_ char *mutable = xstrdup(addrs); - - for (char *addr = strtok(mutable, ", \t\n"); addr; addr = strtok(NULL, ", \t\n")) { - if (strchr(addr, '\'') || strchr(addr, '\\')) - continue; - add_addr(iface, addr); - } -} - -static int get_route_mtu(const char *endpoint) -{ - DEFINE_CMD(c_route); - DEFINE_CMD(c_dev); - regmatch_t matches[2]; - regex_t regex_mtu, regex_dev; - char *route, *mtu, *dev; - - xregcomp(®ex_mtu, "mtu ([0-9]+)", REG_EXTENDED); - xregcomp(®ex_dev, "dev ([^ ]+)", REG_EXTENDED); - - if (strcmp(endpoint, "default")) - route = cmd_ret(&c_route, "ip -o route get %s", endpoint); - else - route = cmd_ret(&c_route, "ip -o route show %s", endpoint); - if (!route) - return -1; - - if (!regexec(®ex_mtu, route, ARRAY_SIZE(matches), matches, 0)) { - route[matches[1].rm_eo] = '\0'; - mtu = &route[matches[1].rm_so]; - } else if (!regexec(®ex_dev, route, ARRAY_SIZE(matches), matches, 0)) { - route[matches[1].rm_eo] = '\0'; - dev = &route[matches[1].rm_so]; - route = cmd_ret(&c_dev, "ip -o link show dev %s", dev); - if (!route) - return -1; - if (regexec(®ex_mtu, route, ARRAY_SIZE(matches), matches, 0)) - return -1; - route[matches[1].rm_eo] = '\0'; - mtu = &route[matches[1].rm_so]; - } else - return -1; - return atoi(mtu); -} - -static void set_mtu(const char *iface, unsigned int mtu) -{ - DEFINE_CMD(c_endpoints); - regex_t regex_endpoint; - regmatch_t matches[2]; - int endpoint_mtu, next_mtu; - - if (mtu) { - cndc("interface setmtu %s %u", iface, mtu); - return; - } - - xregcomp(®ex_endpoint, "^\\[?([a-z0-9:.]+)\\]?:[0-9]+$", REG_EXTENDED); - - endpoint_mtu = get_route_mtu("default"); - if (endpoint_mtu == -1) - endpoint_mtu = 1500; - - for (char *endpoint = cmd_ret(&c_endpoints, "wg show %s endpoints", iface); endpoint; endpoint = cmd_ret(&c_endpoints, NULL)) { - if (regexec(®ex_endpoint, endpoint, ARRAY_SIZE(matches), matches, 0)) - continue; - endpoint[matches[1].rm_eo] = '\0'; - endpoint = &endpoint[matches[1].rm_so]; - - next_mtu = get_route_mtu(endpoint); - if (next_mtu > 0 && next_mtu < endpoint_mtu) - endpoint_mtu = next_mtu; - } - - cndc("interface setmtu %s %d", iface, endpoint_mtu - 80); -} - -static void add_route(const char *iface, unsigned int netid, const char *route) -{ - cndc("network route add %u %s %s", netid, iface, route); -} - -static void set_routes(const char *iface, unsigned int netid) -{ - DEFINE_CMD(c); - - for (char *allowedips = cmd_ret(&c, "wg show %s allowed-ips", iface); allowedips; allowedips = cmd_ret(&c, NULL)) { - char *start = strchr(allowedips, '\t'); - - if (!start) - continue; - ++start; - for (char *allowedip = strtok(start, " \n"); allowedip; allowedip = strtok(NULL, " \n")) - add_route(iface, netid, allowedip); - } -} - -static void set_config(const char *iface, const char *config) -{ - FILE *config_writer; - _cleanup_free_ char *cmd = concat("wg setconf ", iface, " /proc/self/fd/0", NULL); - int ret; - - printf("[#] %s\n", cmd); - - config_writer = popen(cmd, "w"); - if (!config_writer) { - perror("Error: popen"); - exit(errno); - } - if (fputs(config, config_writer) < 0) { - perror("Error: fputs"); - exit(errno); - } - ret = pclose(config_writer); - if (ret) - exit(WIFEXITED(ret) ? WEXITSTATUS(ret) : EIO); -} - -static void broadcast_change(void) -{ - const char *pkg = getenv("CALLING_PACKAGE"); - - if (!pkg || strcmp(pkg, "com.wireguard.android")) - cmd("am broadcast -a com.wireguard.android.WGQUICK_CHANGE com.wireguard.android"); -} - -static void print_search_paths(FILE *file, const char *prefix) -{ - _cleanup_free_ char *paths = strdup(WG_CONFIG_SEARCH_PATHS); - - for (char *path = strtok(paths, " "); path; path = strtok(NULL, " ")) - fprintf(file, "%s%s\n", prefix, path); -} - -static void cmd_usage(const char *program) -{ - printf( "Usage: %s [ up | down ] [ CONFIG_FILE | INTERFACE ]\n" - "\n" - " CONFIG_FILE is a configuration file, whose filename is the interface name\n" - " followed by `.conf'. Otherwise, INTERFACE is an interface name, with\n" - " configuration found at:\n\n", program); - print_search_paths(stdout, " - "); - printf( "\n It is to be readable by wg(8)'s `setconf' sub-command, with the exception\n" - " of the following additions to the [Interface] section, which are handled by\n" - " this program:\n\n" - " - Address: may be specified one or more times and contains one or more\n" - " IP addresses (with an optional CIDR mask) to be set for the interface.\n" - " - MTU: an optional MTU for the interface; if unspecified, auto-calculated.\n" - " - DNS: an optional DNS server to use while the device is up.\n\n" - " See wg-quick(8) for more info and examples.\n"); -} - -static char *cleanup_iface = NULL; - -static void cmd_up_cleanup(void) -{ - is_exiting = true; - if (cleanup_iface) - del_if(cleanup_iface); - free(cleanup_iface); -} - -static void cmd_up(const char *iface, const char *config, unsigned int mtu, const char *addrs, const char *dnses) -{ - DEFINE_CMD(c); - unsigned int netid = 0; - - if (cmd_ret(&c, "ip link show dev %s 2>/dev/null", iface)) { - fprintf(stderr, "Error: %s already exists\n", iface); - exit(EEXIST); - } - - cleanup_iface = xstrdup(iface); - atexit(cmd_up_cleanup); - - add_if(iface); - set_config(iface, config); - set_addr(iface, addrs); - up_if(&netid, iface); - set_dnses(netid, dnses); - set_routes(iface, netid); - set_mtu(iface, mtu); - broadcast_change(); - - free(cleanup_iface); - cleanup_iface = NULL; - exit(EXIT_SUCCESS); -} - -static void cmd_down(const char *iface) -{ - DEFINE_CMD(c); - bool found = false; - - char *ifaces = cmd_ret(&c, "wg show interfaces"); - if (ifaces) { - for (char *eiface = strtok(ifaces, " \n"); eiface; eiface = strtok(NULL, " \n")) { - if (!strcmp(iface, eiface)) { - found = true; - break; - } - } - } - if (!found) { - fprintf(stderr, "Error: %s is not a WireGuard interface\n", iface); - exit(EMEDIUMTYPE); - } - - del_if(iface); - broadcast_change(); - exit(EXIT_SUCCESS); -} - -static void parse_options(char **iface, char **config, unsigned int *mtu, char **addrs, char **dnses, const char *arg) -{ - _cleanup_fclose_ FILE *file = NULL; - _cleanup_free_ char *line = NULL; - _cleanup_free_ char *filename = NULL; - _cleanup_free_ char *paths = strdup(WG_CONFIG_SEARCH_PATHS); - regex_t regex_iface, regex_conf; - regmatch_t matches[2]; - struct stat sbuf; - size_t n = 0; - bool in_interface_section = false; - - *iface = *config = *addrs = *dnses = NULL; - *mtu = 0; - - xregcomp(®ex_iface, "^[a-zA-Z0-9_=+.-]{1,15}$", REG_EXTENDED | REG_NOSUB); - xregcomp(®ex_conf, "/?([a-zA-Z0-9_=+.-]{1,15})\\.conf$", REG_EXTENDED); - - if (!regexec(®ex_iface, arg, 0, NULL, 0)) { - for (char *path = strtok(paths, " "); path; path = strtok(NULL, " ")) { - free(filename); - if (asprintf(&filename, "%s/%s.conf", path, arg) < 0) { - perror("Error: asprintf"); - exit(errno); - } - file = fopen(filename, "r"); - if (file) - break; - } - if (!file) { - fprintf(stderr, "Error: Unable to find configuration file for `%s' in:\n", arg); - print_search_paths(stderr, "- "); - exit(errno); - } - } else { - filename = xstrdup(arg); - file = fopen(filename, "r"); - if (!file) { - fprintf(stderr, "Error: Unable to find configuration file at `%s'\n", filename); - exit(errno); - } - } - - if (regexec(®ex_conf, filename, ARRAY_SIZE(matches), matches, 0)) { - fprintf(stderr, "Error: The config file must be a valid interface name, followed by .conf\n"); - exit(EINVAL); - } - - if (fstat(fileno(file), &sbuf) < 0) { - perror("Error: fstat"); - exit(errno); - } - if (sbuf.st_mode & 0007) - fprintf(stderr, "Warning: `%s' is world accessible\n", filename); - - filename[matches[1].rm_eo] = 0; - *iface = xstrdup(&filename[matches[1].rm_so]); - - while (getline(&line, &n, file) >= 0) { - size_t len = strlen(line), j = 0; - if (len > (1<<16)) - return; - _cleanup_free_ char *clean = xmalloc(len + 1); - - for (size_t i = 0; i < len; ++i) { - if (!isspace(line[i])) - clean[j++] = line[i]; - } - clean[j] = '\0'; - - if (clean[0] == '[') - in_interface_section = false; - if (!strcasecmp(clean, "[Interface]")) - in_interface_section = true; - if (in_interface_section) { - if (!strncasecmp(clean, "Address=", 8) && j > 8) { - *addrs = concat_and_free(*addrs, ",", clean + 8); - continue; - } else if (!strncasecmp(clean, "DNS=", 4) && j > 4) { - *dnses = concat_and_free(*dnses, ",", clean + 4); - continue; - } else if (!strncasecmp(clean, "MTU=", 4) && j > 4) { - *mtu = atoi(clean + 4); - continue; - } - } - *config = concat_and_free(*config, "", line); - } - - if (!*iface) - *iface = xstrdup(""); - if (!*config) - *config = xstrdup(""); - if (!*addrs) - *addrs = xstrdup(""); - if (!*dnses) - *dnses = xstrdup(""); -} - -int main(int argc, char *argv[]) -{ - _cleanup_free_ char *iface = NULL; - _cleanup_free_ char *config = NULL; - _cleanup_free_ char *addrs = NULL; - _cleanup_free_ char *dnses = NULL; - unsigned int mtu; - - if (argc == 2 && (!strcmp(argv[1], "help") || !strcmp(argv[1], "--help") || !strcmp(argv[1], "-h"))) - cmd_usage(argv[0]); - else if (argc == 3 && !strcmp(argv[1], "up")) { - auto_su(argc, argv); - parse_options(&iface, &config, &mtu, &addrs, &dnses, argv[2]); - cmd_up(iface, config, mtu, addrs, dnses); - } else if (argc == 3 && !strcmp(argv[1], "down")) { - auto_su(argc, argv); - parse_options(&iface, &config, &mtu, &addrs, &dnses, argv[2]); - cmd_down(iface); - } else { - cmd_usage(argv[0]); - return 1; - } - return 0; -} |