=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/sshbuf-getput-basic.c,v retrieving revision 1.3 retrieving revision 1.4 diff -u -r1.3 -r1.4 --- src/usr.bin/ssh/sshbuf-getput-basic.c 2015/01/12 15:18:07 1.3 +++ src/usr.bin/ssh/sshbuf-getput-basic.c 2015/01/14 15:02:39 1.4 @@ -1,4 +1,4 @@ -/* $OpenBSD: sshbuf-getput-basic.c,v 1.3 2015/01/12 15:18:07 djm Exp $ */ +/* $OpenBSD: sshbuf-getput-basic.c,v 1.4 2015/01/14 15:02:39 djm Exp $ */ /* * Copyright (c) 2011 Damien Miller * @@ -420,5 +420,41 @@ d[4] = 0; if (len != 0) memcpy(d + 4 + prepend, s, len); + return 0; +} + +int +sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf, + const u_char **valp, size_t *lenp) +{ + const u_char *d; + size_t len, olen; + int r; + + if ((r = sshbuf_peek_string_direct(buf, &d, &olen)) < 0) + return r; + len = olen; + /* Refuse negative (MSB set) bignums */ + if ((len != 0 && (*d & 0x80) != 0)) + return SSH_ERR_BIGNUM_IS_NEGATIVE; + /* Refuse overlong bignums, allow prepended \0 to avoid MSB set */ + if (len > SSHBUF_MAX_BIGNUM + 1 || + (len == SSHBUF_MAX_BIGNUM + 1 && *d != 0)) + return SSH_ERR_BIGNUM_TOO_LARGE; + /* Trim leading zeros */ + while (len > 0 && *d == 0x00) { + d++; + len--; + } + if (valp != 0) + *valp = d; + if (lenp != NULL) + *lenp = len; + if (sshbuf_consume(buf, olen + 4) != 0) { + /* Shouldn't happen */ + SSHBUF_DBG(("SSH_ERR_INTERNAL_ERROR")); + SSHBUF_ABORT(); + return SSH_ERR_INTERNAL_ERROR; + } return 0; }