Problem - Kevin Tafuro

strncpy(a.sun_path, EGD_SOCKET_PATH, sizeof(a.sun_path));
a.sun_path[sizeof(a.sun_path) - 1] = 0;
if (connect(spc_egd_fd, (struct sockaddr *)&a, sizeof(a))) {
perror("Entropy server connection failed");
exit(-1);
}
}
unsigned char *spc_keygen(unsigned char *buf, size_t l) {
ssize_t nb;
unsigned char nbytes, *p, tbytes;
static unsigned char cmd[2] = {0x01,};
if (spc_egd_fd = = -1) spc_rand_init( );
for (p = buf; l; l -= tbytes) {
/* Build and send the request command to the EGD server */
cmd[1] = (l > 255 ? 255 : l);
do {
if ((nb = write(spc_egd_fd, cmd, sizeof(cmd))) = = -1 && errno != EINTR) {
perror("Communication with entropy server failed");
exit(-1);
}
} while (nb = = -1);
/* Get the number of bytes in the result */
do {
if ((nb = read(spc_egd_fd, &nbytes, 1)) = = -1 && errno != EINTR) {
perror("Communication with entropy server failed");
exit(-1);
}
} while (nb = = -1);
tbytes = nbytes;
/* Get all of the data from the result */
while (nbytes) {
do {
if ((nb = read(spc_egd_fd, p, nbytes)) = = -1) {
if (errno = = -1) continue;
perror("Communication with entropy server failed");
exit(-1);
}
} while (nb = = -1);
p += nb;
nbytes -= nb;
}
/* If we didn't get as much entropy as we asked for, the server has no more
* left, so we must fall back on the application-level generator to avoid
* blocking.
*/
if (tbytes != cmd[l]) {
spc_rand(p, l);
break;
}
Using an Entropy Gathering Daemon–Compatible Solution | 597
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