diff options
Diffstat (limited to 'swaylock/shadow.c')
| -rw-r--r-- | swaylock/shadow.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/swaylock/shadow.c b/swaylock/shadow.c index 1f10514c..f928eaa3 100644 --- a/swaylock/shadow.c +++ b/swaylock/shadow.c @@ -6,9 +6,21 @@ #include <unistd.h> #include <wlr/util/log.h> #include "swaylock/swaylock.h" +#ifdef __GLIBC__ +// GNU, you damn slimy bastard +#include <crypt.h> +#endif static int comm[2][2]; +static void clear_buffer(void *buf, size_t bytes) { + volatile char *buffer = buf; + volatile char zero = '\0'; + for (size_t i = 0; i < bytes; ++i) { + buffer[i] = zero; + } +} + void run_child(void) { /* This code runs as root */ struct passwd *pwent = getpwuid(getuid()); @@ -25,6 +37,17 @@ void run_child(void) { } encpw = swent->sp_pwdp; } + + /* We don't need any additional logging here because the parent process will + * also fail here and will handle logging for us. */ + if (setgid(getgid()) != 0) { + exit(EXIT_FAILURE); + } + if (setuid(getuid()) != 0) { + exit(EXIT_FAILURE); + } + + /* This code does not run as root */ wlr_log(WLR_DEBUG, "prepared to authorize user %s", pwent->pw_name); size_t size; @@ -60,10 +83,14 @@ void run_child(void) { result = strcmp(c, encpw) == 0; if (write(comm[1][1], &result, sizeof(result)) != sizeof(result)) { wlr_log_errno(WLR_ERROR, "failed to write pw check result"); + clear_buffer(buf, size); exit(EXIT_FAILURE); } + clear_buffer(buf, size); free(buf); } + + clear_buffer(encpw, strlen(encpw)); exit(EXIT_SUCCESS); } |