va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
+ fflush(stderr);
}
void logfunc(int level, const char* string) {
int write_datum_fd_with_length(int fd, const gnutls_datum_t* d) {
- uint32_t len = htonl(d->size);
+ uint32_t len;
+ int looks_negative = (d->data[0] & 0x80);
+ unsigned char zero = 0;
+
+ /* if the first bit is 1, then the datum will appear negative in the
+ MPI encoding style used by OpenSSH. In that case, we'll increase
+ the length by one, and dump out one more byte */
+
+ if (looks_negative) {
+ len = htonl(d->size + 1);
+ } else {
+ len = htonl(d->size);
+ }
if (write(fd, &len, sizeof(len)) != sizeof(len)) {
err("failed to write size of datum.\n");
return -2;
}
+ if (looks_negative) {
+ if (write(fd, &zero, 1) != 1) {
+ err("failed to write padding byte for MPI.\n");
+ return -2;
+ }
+ }
return write_datum_fd(fd, d);
}
}
execv(path, argv);
err("exec %s failed (error: %d \"%s\")\n", path, errno, strerror(errno));
+ /* close the open file descriptors */
+ close(p[0]);
+ close(0);
+
exit(1);
} else { /* this is the parent */
close(p[0]); /* close unused read end */
setlocale(LC_ALL, oldlocale);
return 1;
}
+
+/* http://tools.ietf.org/html/rfc4880#section-5.5.2 */
+size_t get_openpgp_mpi_size(gnutls_datum_t* d) {
+ return 2 + d->size;
+}
+
+int write_openpgp_mpi_to_fd(int fd, gnutls_datum_t* d) {
+ uint16_t x;
+
+ x = d->size * 8;
+ x = htons(x);
+
+ write(fd, &x, sizeof(x));
+ write(fd, d->data, d->size);
+
+ return 0;
+}