diff --git a/README.md b/README.md index a492cc2..b25ac06 100644 --- a/README.md +++ b/README.md @@ -35,12 +35,12 @@ rdo [command] The configuration file has the following variables: ``` -username=sw1tchbl4d3 +group=wheel wrong_pw_sleep=1000 session_ttl=5 ``` -- `username`: The username of the user that is allowed to execute rdo (no multi user or group support (yet)). +- `group`: The group of users that is allowed to execute rdo. - `wrong_pw_sleep`: The amount of milliseconds to sleep at a wrong password attempt. Must be a positive integer. Set to 0 to disable. - `session_ttl`: The amount of minutes a session lasts. Must be a positive integer. Set to 0 to disable. diff --git a/rdo.c b/rdo.c index 0d28ca6..6eb13bc 100644 --- a/rdo.c +++ b/rdo.c @@ -1,4 +1,5 @@ #include +#include #include #include #include @@ -46,7 +47,7 @@ void runprog(char** program_argv) { } int main(int argc, char** argv) { - char username[64], wrong_pw_sleep[64], session_ttl[64], password[128]; + char groupname[64], wrong_pw_sleep[64], session_ttl[64], password[128]; unsigned int sleep_us, tries, ts_ttl; if (argc == 1) { @@ -67,7 +68,7 @@ int main(int argc, char** argv) { if (!fp) err(1, "Could not open /etc/rdo.conf"); - getconf(fp, "username", username, sizeof(username)); + getconf(fp, "group", groupname, sizeof(groupname)); getconf(fp, "wrong_pw_sleep", wrong_pw_sleep, sizeof(wrong_pw_sleep)); getconf(fp, "session_ttl", session_ttl, sizeof(session_ttl)); sleep_us = atoi(wrong_pw_sleep) * 1000; @@ -75,22 +76,38 @@ int main(int argc, char** argv) { fclose(fp); - if (getsession(getppid(), ts_ttl) == 0) + if (getsession(getppid(), ts_ttl, ruid) == 0) runprog(&argv[1]); - struct passwd* p = getpwnam(username); - if (!p) { + struct passwd* pw = getpwuid(ruid); + if (!pw) { if (errno == 0) - errx(1, "The user specified in the config file does not exist."); + errx(1, "No user with UID %d", ruid); else err(1, "Could not get user info"); } - int uid = p->pw_uid; - if (uid != ruid) + struct group* current_group_entry = getgrent(); + while (current_group_entry) { + if (strcmp(current_group_entry->gr_name, groupname) == 0) + break; + current_group_entry = getgrent(); + } + + if (!current_group_entry) + errx(1, "The group '%s' does not exist.", groupname); + + char* current_member = current_group_entry->gr_mem[0]; + for (int i = 1; current_member; i++) { + if (strcmp(current_member, pw->pw_name) == 0) + break; + current_member = current_group_entry->gr_mem[i]; + } + + if (!current_member) errx(1, "You are not allowed to execute rdo."); - struct spwd* shadowEntry = getspnam(p->pw_name); + struct spwd* shadowEntry = getspnam(pw->pw_name); if (!shadowEntry || !shadowEntry->sp_pwdp) err(1, "Could not get shadow entry"); @@ -107,7 +124,7 @@ int main(int argc, char** argv) { errx(1, "Could not hash password, does your user have a password?"); if (strcmp(shadowEntry->sp_pwdp, hashed_pw) == 0) { - setsession(getppid(), ts_ttl); + setsession(getppid(), ts_ttl, ruid); runprog(&argv[1]); } diff --git a/rdo_sample.conf b/rdo_sample.conf index 94842f1..5d19f10 100644 --- a/rdo_sample.conf +++ b/rdo_sample.conf @@ -1,3 +1,3 @@ -username=sw1tchbl4d3 +group=wheel wrong_pw_sleep=1000 session_ttl=5 diff --git a/sessions.h b/sessions.h index dd04e92..9c82b58 100644 --- a/sessions.h +++ b/sessions.h @@ -77,7 +77,7 @@ int ensuredir() { return 0; } -void setsession(int pid, unsigned int ts_ttl) { +void setsession(int pid, unsigned int ts_ttl, int ruid) { unsigned long long startts; char path[1024], ts_str[32]; @@ -87,7 +87,7 @@ void setsession(int pid, unsigned int ts_ttl) { if (ensuredir() < 0 || getpstartts(pid, &startts) < 0) return; - snprintf(path, sizeof(path), "/run/rdo/%d-%llu", pid, startts); + snprintf(path, sizeof(path), "/run/rdo/%d-%d-%llu", ruid, pid, startts); int fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0700); if (fd < 0) { @@ -108,7 +108,7 @@ void setsession(int pid, unsigned int ts_ttl) { return; } -int getsession(int pid, unsigned int ts_ttl) { +int getsession(int pid, unsigned int ts_ttl, int ruid) { unsigned long long startts, current; char path[1024], ts_str[32]; @@ -118,7 +118,7 @@ int getsession(int pid, unsigned int ts_ttl) { if (ensuredir() < 0 || getpstartts(pid, &startts) < 0) return -1; - snprintf(path, sizeof(path), "/run/rdo/%d-%llu", pid, startts); + snprintf(path, sizeof(path), "/run/rdo/%d-%d-%llu", ruid, pid, startts); int fd = open(path, O_RDONLY); if (fd < 0) {