diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Makefile.am | 4 | ||||
| -rw-r--r-- | src/utils.c | 28 |
2 files changed, 28 insertions, 4 deletions
diff --git a/src/Makefile.am b/src/Makefile.am index 6f9ca23..97b4545 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -30,6 +30,10 @@ if USE_CUSTOMRNG ptunnel_ng_CFLAGS += -DUSE_CUSTOMRNG=1 endif +if USE_RNGFALLBACK +ptunnel_ng_CFLAGS += -DUSE_RNGFALLBACK=1 +endif + ptunnel_ng_SOURCES = \ md5.c \ challenge.c \ diff --git a/src/utils.c b/src/utils.c index 64f6f88..6752890 100644 --- a/src/utils.c +++ b/src/utils.c @@ -174,12 +174,32 @@ int pt_random(void) { } bytes_read = read(rng_fd, &rnd_val, sizeof rnd_val); if (bytes_read != sizeof rnd_val) { - if (bytes_read < 0) - pt_log(kLog_error, "FATAL: Read from random device failed: %s\n", + if (bytes_read < 0) { + pt_log(kLog_error, "Read from random device failed: %s\n", strerror(errno)); - else - pt_log(kLog_error, "FATAL: Read only %zd bytes (wanted %zd bytes)\n", + } else { + pt_log(kLog_info, "Read only %zd random bytes (wanted %zd bytes)\n", bytes_read, sizeof rnd_val); + } +#ifdef USE_RNGFALLBACK + /* use /dev/urandom if previous random device failed */ + static int fallback_rng_fd = -1; + if (fallback_rng_fd < 0) { + fallback_rng_fd = open("/dev/urandom", O_RDONLY); + if (fallback_rng_fd < 0) { + pt_log(kLog_error, "FATAL: Could not open fallback random device '%s': %s\n", + "/dev/urandom", strerror(errno)); + exit(EXIT_FAILURE); + } + } + if (bytes_read < 0) { + bytes_read = 0; + } + if (read(fallback_rng_fd, &rnd_val + bytes_read, sizeof rnd_val - bytes_read) == sizeof rnd_val - bytes_read) { + return rnd_val; + } +#endif + pt_log(kLog_error, "FATAL: No more RNG sources available\n"); exit(EXIT_FAILURE); } return rnd_val; |