diff options
Diffstat (limited to 'daemon.c')
| -rw-r--r-- | daemon.c | 262 |
1 files changed, 151 insertions, 111 deletions
@@ -5,8 +5,6 @@ #include "strbuf.h" #include "string-list.h" -#include <syslog.h> - #ifndef HOST_NAME_MAX #define HOST_NAME_MAX 256 #endif @@ -29,10 +27,10 @@ static const char daemon_usage[] = " [--strict-paths] [--base-path=<path>] [--base-path-relaxed]\n" " [--user-path | --user-path=<path>]\n" " [--interpolated-path=<path>]\n" -" [--reuseaddr] [--detach] [--pid-file=<file>]\n" +" [--reuseaddr] [--pid-file=<file>]\n" " [--(enable|disable|allow-override|forbid-override)=<service>]\n" " [--inetd | [--listen=<host_or_ipaddr>] [--port=<n>]\n" -" [--user=<user> [--group=<group>]]\n" +" [--detach] [--user=<user> [--group=<group>]]\n" " [<directory>...]"; /* List of acceptable pathname prefixes */ @@ -73,12 +71,14 @@ static void logreport(int priority, const char *err, va_list params) syslog(priority, "%s", buf); } else { /* - * Since stderr is set to linebuffered mode, the + * Since stderr is set to buffered mode, the * logging of different processes will not overlap + * unless they overflow the (rather big) buffers. */ fprintf(stderr, "[%"PRIuMAX"] ", (uintmax_t)getpid()); vfprintf(stderr, err, params); fputc('\n', stderr); + fflush(stderr); } } @@ -520,37 +520,14 @@ static void parse_host_arg(char *extra_args, int buflen) } -static int execute(struct sockaddr *addr) +static int execute(void) { static char line[1000]; int pktlen, len, i; + char *addr = getenv("REMOTE_ADDR"), *port = getenv("REMOTE_PORT"); - if (addr) { - char addrbuf[256] = ""; - int port = -1; - - if (addr->sa_family == AF_INET) { - struct sockaddr_in *sin_addr = (void *) addr; - inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf, sizeof(addrbuf)); - port = ntohs(sin_addr->sin_port); -#ifndef NO_IPV6 - } else if (addr && addr->sa_family == AF_INET6) { - struct sockaddr_in6 *sin6_addr = (void *) addr; - - char *buf = addrbuf; - *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */ - inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, sizeof(addrbuf) - 1); - strcat(buf, "]"); - - port = ntohs(sin6_addr->sin6_port); -#endif - } - loginfo("Connection from %s:%d", addrbuf, port); - setenv("REMOTE_ADDR", addrbuf, 1); - } - else { - unsetenv("REMOTE_ADDR"); - } + if (addr) + loginfo("Connection from %s:%s", addr, port); alarm(init_timeout ? init_timeout : timeout); pktlen = packet_read_line(0, line, sizeof(line)); @@ -620,17 +597,17 @@ static unsigned int live_children; static struct child { struct child *next; - pid_t pid; + struct child_process cld; struct sockaddr_storage address; } *firstborn; -static void add_child(pid_t pid, struct sockaddr *addr, int addrlen) +static void add_child(struct child_process *cld, struct sockaddr *addr, socklen_t addrlen) { struct child *newborn, **cradle; newborn = xcalloc(1, sizeof(*newborn)); live_children++; - newborn->pid = pid; + memcpy(&newborn->cld, cld, sizeof(*cld)); memcpy(&newborn->address, addr, addrlen); for (cradle = &firstborn; *cradle; cradle = &(*cradle)->next) if (!addrcmp(&(*cradle)->address, &newborn->address)) @@ -639,19 +616,6 @@ static void add_child(pid_t pid, struct sockaddr *addr, int addrlen) *cradle = newborn; } -static void remove_child(pid_t pid) -{ - struct child **cradle, *blanket; - - for (cradle = &firstborn; (blanket = *cradle); cradle = &blanket->next) - if (blanket->pid == pid) { - *cradle = blanket->next; - live_children--; - free(blanket); - break; - } -} - /* * This gets called if the number of connections grows * past "max_connections". @@ -667,7 +631,7 @@ static void kill_some_child(void) for (; (next = blanket->next); blanket = next) if (!addrcmp(&blanket->address, &next->address)) { - kill(blanket->pid, SIGTERM); + kill(blanket->cld.pid, SIGTERM); break; } } @@ -677,18 +641,28 @@ static void check_dead_children(void) int status; pid_t pid; - while ((pid = waitpid(-1, &status, WNOHANG)) > 0) { - const char *dead = ""; - remove_child(pid); - if (!WIFEXITED(status) || (WEXITSTATUS(status) > 0)) - dead = " (with error)"; - loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead); - } + struct child **cradle, *blanket; + for (cradle = &firstborn; (blanket = *cradle);) + if ((pid = waitpid(blanket->cld.pid, &status, WNOHANG)) > 1) { + const char *dead = ""; + if (status) + dead = " (with error)"; + loginfo("[%"PRIuMAX"] Disconnected%s", (uintmax_t)pid, dead); + + /* remove the child */ + *cradle = blanket->next; + live_children--; + free(blanket); + } else + cradle = &blanket->next; } -static void handle(int incoming, struct sockaddr *addr, int addrlen) +static char **cld_argv; +static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen) { - pid_t pid; + struct child_process cld = { 0 }; + char addrbuf[300] = "REMOTE_ADDR=", portbuf[300]; + char *env[] = { addrbuf, portbuf, NULL }; if (max_connections && live_children >= max_connections) { kill_some_child(); @@ -701,22 +675,37 @@ static void handle(int incoming, struct sockaddr *addr, int addrlen) } } - if ((pid = fork())) { - close(incoming); - if (pid < 0) { - logerror("Couldn't fork %s", strerror(errno)); - return; - } + if (addr->sa_family == AF_INET) { + struct sockaddr_in *sin_addr = (void *) addr; + inet_ntop(addr->sa_family, &sin_addr->sin_addr, addrbuf + 12, + sizeof(addrbuf) - 12); + snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d", + ntohs(sin_addr->sin_port)); +#ifndef NO_IPV6 + } else if (addr && addr->sa_family == AF_INET6) { + struct sockaddr_in6 *sin6_addr = (void *) addr; - add_child(pid, addr, addrlen); - return; + char *buf = addrbuf + 12; + *buf++ = '['; *buf = '\0'; /* stpcpy() is cool */ + inet_ntop(AF_INET6, &sin6_addr->sin6_addr, buf, + sizeof(addrbuf) - 13); + strcat(buf, "]"); + + snprintf(portbuf, sizeof(portbuf), "REMOTE_PORT=%d", + ntohs(sin6_addr->sin6_port)); +#endif } - dup2(incoming, 0); - dup2(incoming, 1); - close(incoming); + cld.env = (const char **)env; + cld.argv = (const char **)cld_argv; + cld.in = incoming; + cld.out = dup(incoming); - exit(execute(addr)); + if (start_command(&cld)) + logerror("unable to fork"); + else + add_child(&cld, addr, addrlen); + close(incoming); } static void child_handler(int signo) @@ -918,9 +907,15 @@ static int service_loop(struct socketlist *socklist) for (i = 0; i < socklist->nr; i++) { if (pfd[i].revents & POLLIN) { - struct sockaddr_storage ss; - unsigned int sslen = sizeof(ss); - int incoming = accept(pfd[i].fd, (struct sockaddr *)&ss, &sslen); + union { + struct sockaddr sa; + struct sockaddr_in sai; +#ifndef NO_IPV6 + struct sockaddr_in6 sai6; +#endif + } ss; + socklen_t sslen = sizeof(ss); + int incoming = accept(pfd[i].fd, &ss.sa, &sslen); if (incoming < 0) { switch (errno) { case EAGAIN: @@ -931,7 +926,7 @@ static int service_loop(struct socketlist *socklist) die_errno("accept returned"); } } - handle(incoming, (struct sockaddr *)&ss, sslen); + handle(incoming, &ss.sa, sslen); } } } @@ -949,6 +944,62 @@ static void sanitize_stdfds(void) close(fd); } +#ifdef NO_POSIX_GOODIES + +struct credentials; + +static void drop_privileges(struct credentials *cred) +{ + /* nothing */ +} + +static void daemonize(void) +{ + die("--detach not supported on this platform"); +} + +static struct credentials *prepare_credentials(const char *user_name, + const char *group_name) +{ + die("--user not supported on this platform"); +} + +#else + +struct credentials { + struct passwd *pass; + gid_t gid; +}; + +static void drop_privileges(struct credentials *cred) +{ + if (cred && (initgroups(cred->pass->pw_name, cred->gid) || + setgid (cred->gid) || setuid(cred->pass->pw_uid))) + die("cannot drop privileges"); +} + +static struct credentials *prepare_credentials(const char *user_name, + const char *group_name) +{ + static struct credentials c; + + c.pass = getpwnam(user_name); + if (!c.pass) + die("user not found - %s", user_name); + + if (!group_name) + c.gid = c.pass->pw_gid; + else { + struct group *group = getgrnam(group_name); + if (!group) + die("group not found - %s", group_name); + + c.gid = group->gr_gid; + } + + return &c; +} + static void daemonize(void) { switch (fork()) { @@ -966,6 +1017,7 @@ static void daemonize(void) close(2); sanitize_stdfds(); } +#endif static void store_pid(const char *path) { @@ -976,7 +1028,8 @@ static void store_pid(const char *path) die_errno("failed to write pid file '%s'", path); } -static int serve(struct string_list *listen_addr, int listen_port, struct passwd *pass, gid_t gid) +static int serve(struct string_list *listen_addr, int listen_port, + struct credentials *cred) { struct socketlist socklist = { NULL, 0, 0 }; @@ -985,10 +1038,7 @@ static int serve(struct string_list *listen_addr, int listen_port, struct passwd die("unable to allocate any listen sockets on port %u", listen_port); - if (pass && gid && - (initgroups(pass->pw_name, gid) || setgid (gid) || - setuid(pass->pw_uid))) - die("cannot drop privileges"); + drop_privileges(cred); return service_loop(&socklist); } @@ -997,12 +1047,10 @@ int main(int argc, char **argv) { int listen_port = 0; struct string_list listen_addr = STRING_LIST_INIT_NODUP; - int inetd_mode = 0; + int serve_mode = 0, inetd_mode = 0; const char *pid_file = NULL, *user_name = NULL, *group_name = NULL; int detach = 0; - struct passwd *pass = NULL; - struct group *group; - gid_t gid = 0; + struct credentials *cred = NULL; int i; git_extract_argv0_path(argv[0]); @@ -1023,6 +1071,10 @@ int main(int argc, char **argv) continue; } } + if (!strcmp(arg, "--serve")) { + serve_mode = 1; + continue; + } if (!strcmp(arg, "--inetd")) { inetd_mode = 1; log_syslog = 1; @@ -1131,10 +1183,10 @@ int main(int argc, char **argv) set_die_routine(daemon_die); } else /* avoid splitting a message in the middle */ - setvbuf(stderr, NULL, _IOLBF, 0); + setvbuf(stderr, NULL, _IOFBF, 4096); - if (inetd_mode && (group_name || user_name)) - die("--user and --group are incompatible with --inetd"); + if (inetd_mode && (detach || group_name || user_name)) + die("--detach, --user and --group are incompatible with --inetd"); if (inetd_mode && (listen_port || (listen_addr.nr > 0))) die("--listen= and --port= are incompatible with --inetd"); @@ -1144,21 +1196,8 @@ int main(int argc, char **argv) if (group_name && !user_name) die("--group supplied without --user"); - if (user_name) { - pass = getpwnam(user_name); - if (!pass) - die("user not found - %s", user_name); - - if (!group_name) - gid = pass->pw_gid; - else { - group = getgrnam(group_name); - if (!group) - die("group not found - %s", group_name); - - gid = group->gr_gid; - } - } + if (user_name) + cred = prepare_credentials(user_name, group_name); if (strict_paths && (!ok_paths || !*ok_paths)) die("option --strict-paths requires a whitelist"); @@ -1168,19 +1207,13 @@ int main(int argc, char **argv) base_path); if (inetd_mode) { - struct sockaddr_storage ss; - struct sockaddr *peer = (struct sockaddr *)&ss; - socklen_t slen = sizeof(ss); - if (!freopen("/dev/null", "w", stderr)) die_errno("failed to redirect stderr to /dev/null"); - - if (getpeername(0, peer, &slen)) - peer = NULL; - - return execute(peer); } + if (inetd_mode || serve_mode) + return execute(); + if (detach) { daemonize(); loginfo("Ready to rumble"); @@ -1191,5 +1224,12 @@ int main(int argc, char **argv) if (pid_file) store_pid(pid_file); - return serve(&listen_addr, listen_port, pass, gid); + /* prepare argv for serving-processes */ + cld_argv = xmalloc(sizeof (char *) * (argc + 2)); + for (i = 0; i < argc; ++i) + cld_argv[i] = argv[i]; + cld_argv[argc] = "--serve"; + cld_argv[argc+1] = NULL; + + return serve(&listen_addr, listen_port, cred); } |