diff options
Diffstat (limited to 'source4/heimdal/lib/hcrypto/rand-fortuna.c')
| -rw-r--r-- | source4/heimdal/lib/hcrypto/rand-fortuna.c | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/source4/heimdal/lib/hcrypto/rand-fortuna.c b/source4/heimdal/lib/hcrypto/rand-fortuna.c index 6cc4267c13..1d47ed49cc 100644 --- a/source4/heimdal/lib/hcrypto/rand-fortuna.c +++ b/source4/heimdal/lib/hcrypto/rand-fortuna.c @@ -33,7 +33,7 @@ #include <config.h> #endif -RCSID("$Id: rand-fortuna.c 20029 2007-01-21 09:55:42Z lha $"); +RCSID("$Id: rand-fortuna.c 21196 2007-06-20 05:08:58Z lha $"); #include <stdio.h> #include <stdlib.h> @@ -427,6 +427,8 @@ extract_data(FState * st, unsigned count, unsigned char *dst) static FState main_state; static int init_done; static int have_entropy; +#define FORTUNA_RESEED_BYTE 10000 +static unsigned resend_bytes; /* * Try our best to do an inital seed @@ -472,6 +474,35 @@ fortuna_reseed(void) memset(buf, 0, sizeof(buf)); } } + /* + * Fall back to gattering data from timer and secret files, this + * is really the last resort. + */ + if (!entropy_p) { + /* to save stackspace */ + union { + unsigned char buf[INIT_BYTES]; + unsigned char shad[1001]; + } u; + int fd; + + /* add timer info */ + if ((*hc_rand_timer_method.bytes)(u.buf, sizeof(u.buf)) == 1) + add_entropy(&main_state, u.buf, sizeof(u.buf)); + /* add /etc/shadow */ + fd = open("/etc/shadow", O_RDONLY, 0); + if (fd >= 0) { + ssize_t n; + /* add_entropy will hash the buf */ + while ((n = read(fd, (char *)u.shad, sizeof(u.shad))) > 0) + add_entropy(&main_state, u.shad, sizeof(u.shad)); + close(fd); + } + + memset(&u, 0, sizeof(u)); + + entropy_p = 1; /* sure about this ? */ + } { pid_t pid = getpid(); add_entropy(&main_state, (void *)&pid, sizeof(pid)); @@ -517,6 +548,11 @@ fortuna_bytes(unsigned char *outdata, int size) { if (!fortuna_init()) return 0; + resend_bytes += size; + if (resend_bytes > FORTUNA_RESEED_BYTE || resend_bytes < size) { + resend_bytes = 0; + fortuna_reseed(); + } extract_data(&main_state, size, outdata); return 1; } |