diff --git a/src/wg-quick/android.c b/src/wg-quick/android.c index b2ca814..12108c0 100644 --- a/src/wg-quick/android.c +++ b/src/wg-quick/android.c @@ -34,6 +34,15 @@ static bool is_exiting = false; +/* TODO: remove this once the NDK supports it. */ +static char *strchrnul(const char *s, int c) +{ + char *x = strchr(s, c); + if (!x) + return (char *)s + strlen(s); + return x; +} + static void *xmalloc(size_t size) { void *ret = malloc(size); @@ -43,6 +52,15 @@ static void *xmalloc(size_t size) exit(errno); } +static void *xcalloc(size_t nmemb, size_t size) +{ + void *ret = calloc(nmemb, size); + if (ret) + return ret; + perror("Error: calloc"); + exit(errno); +} + static void *xstrdup(const char *str) { char *ret = strdup(str); @@ -288,9 +306,79 @@ static void up_if(unsigned int *netid, const char *iface) cndc("network interface add %u %s", *netid, iface); } -static void set_users(unsigned int netid) +static int compare_uid(const void *a, const void *b) { - cndc("network users add %u 0-99999", netid); + return *(const uid_t *)a - *(const uid_t *)b; +} + +static uid_t *get_uid_list(const char *selected_applications) +{ + _cleanup_fclose_ FILE *package_list = NULL; + _cleanup_free_ char *line = NULL; + uid_t package_uid; + size_t line_len = 0, i; + const char *comma, *start; + uid_t *uid_list; + + if (!selected_applications) + return xcalloc(1, sizeof(*uid_list)); + + for (i = 1, comma = selected_applications; comma; comma = strchr(comma + 1, ','), ++i); + uid_list = xcalloc(i, sizeof(*uid_list)); + i = 0; + + package_list = fopen("/data/system/packages.list", "r"); + if (!package_list) { + perror("Error: Unable to open package list"); + exit(errno); + } + + while (getline(&line, &line_len, package_list) >= 0) { + char *package_name, *package_uid_str, *endptr; + + package_name = line; + package_uid_str = strchr(package_name, ' '); + if (!package_uid_str) + continue; + *package_uid_str++ = '\0'; + *strchrnul(package_uid_str, ' ') = '\0'; + package_uid = strtoul(package_uid_str, &endptr, 10); + if (!package_uid || !*package_uid_str || *endptr) + continue; + + for (start = selected_applications; comma = strchrnul(start, ','), *start; start = comma + 1) { + ptrdiff_t token_len = comma - start; + + if (token_len && strlen(package_name) == token_len && !strncmp(start, package_name, token_len)) + uid_list[i++] = package_uid; + } + } + qsort(uid_list, i, sizeof(*uid_list), compare_uid); + return uid_list; +} + +static void set_users(unsigned int netid, const char *excluded_applications) +{ + _cleanup_free_ uid_t *excluded_uids = get_uid_list(excluded_applications); + _cleanup_free_ char *ranges = NULL; + char range[22]; + uid_t start; + + for (start = 0; *excluded_uids; start = *excluded_uids + 1, ++excluded_uids) { + if (start > *excluded_uids - 1) + continue; + else if (start == *excluded_uids - 1) + snprintf(range, sizeof(range), "%u", start); + else + snprintf(range, sizeof(range), "%u-%u", start, *excluded_uids - 1); + ranges = concat_and_free(ranges, " ", range); + } + if (start < 99999) { + snprintf(range, sizeof(range), "%u-99999", start); + ranges = concat_and_free(ranges, " ", range); + } + + cndc("network users add %u %s", netid, ranges); } static void set_dnses(unsigned int netid, const char *dnses) @@ -536,7 +624,8 @@ static void cmd_usage(const char *program) " - 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" + " - DNS: an optional DNS server to use while the device is up.\n" + " - ExcludedApplications: optional applications to exclude from the tunnel.\n\n" " See wg-quick(8) for more info and examples.\n"); } @@ -550,7 +639,7 @@ static void cmd_up_cleanup(void) free(cleanup_iface); } -static void cmd_up(const char *iface, const char *config, unsigned int mtu, const char *addrs, const char *dnses) +static void cmd_up(const char *iface, const char *config, unsigned int mtu, const char *addrs, const char *dnses, const char *excluded_applications) { DEFINE_CMD(c); unsigned int netid = 0; @@ -571,7 +660,7 @@ static void cmd_up(const char *iface, const char *config, unsigned int mtu, cons set_dnses(netid, dnses); set_routes(iface, netid); set_mtu(iface, mtu); - set_users(netid); + set_users(netid, excluded_applications); broadcast_change(); free(cleanup_iface); @@ -604,7 +693,7 @@ static void cmd_down(const char *iface) exit(EXIT_SUCCESS); } -static void parse_options(char **iface, char **config, unsigned int *mtu, char **addrs, char **dnses, const char *arg) +static void parse_options(char **iface, char **config, unsigned int *mtu, char **addrs, char **dnses, char **excluded_applications, const char *arg) { _cleanup_fclose_ FILE *file = NULL; _cleanup_free_ char *line = NULL; @@ -685,6 +774,9 @@ static void parse_options(char **iface, char **config, unsigned int *mtu, char * } else if (!strncasecmp(clean, "DNS=", 4) && j > 4) { *dnses = concat_and_free(*dnses, ",", clean + 4); continue; + } else if (!strncasecmp(clean, "ExcludedApplications=", 21) && j > 4) { + *excluded_applications = concat_and_free(*excluded_applications, ",", clean + 21); + continue; } else if (!strncasecmp(clean, "MTU=", 4) && j > 4) { *mtu = atoi(clean + 4); continue; @@ -709,17 +801,18 @@ int main(int argc, char *argv[]) _cleanup_free_ char *config = NULL; _cleanup_free_ char *addrs = NULL; _cleanup_free_ char *dnses = NULL; + _cleanup_free_ char *excluded_applications = 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); + parse_options(&iface, &config, &mtu, &addrs, &dnses, &excluded_applications, argv[2]); + cmd_up(iface, config, mtu, addrs, dnses, excluded_applications); } else if (argc == 3 && !strcmp(argv[1], "down")) { auto_su(argc, argv); - parse_options(&iface, &config, &mtu, &addrs, &dnses, argv[2]); + parse_options(&iface, &config, &mtu, &addrs, &dnses, &excluded_applications, argv[2]); cmd_down(iface); } else { cmd_usage(argv[0]);