1 /* $OpenBSD: dispatch.c,v 1.27 2015/05/01 07:10:01 djm Exp $ */ 2 /* 3 * Copyright (c) 2000 Markus Friedl. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include <sys/types.h> 27 28 #include <signal.h> 29 #include <stdarg.h> 30 31 #include "ssh1.h" 32 #include "ssh2.h" 33 #include "log.h" 34 #include "dispatch.h" 35 #include "packet.h" 36 #include "compat.h" 37 #include "ssherr.h" 38 39 int 40 dispatch_protocol_error(int type, u_int32_t seq, void *ctx) 41 { 42 struct ssh *ssh = active_state; /* XXX */ 43 int r; 44 45 logit("dispatch_protocol_error: type %d seq %u", type, seq); 46 if (!compat20) 47 fatal("protocol error"); 48 if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 || 49 (r = sshpkt_put_u32(ssh, seq)) != 0 || 50 (r = sshpkt_send(ssh)) != 0 || 51 (r = ssh_packet_write_wait(ssh)) != 0) 52 sshpkt_fatal(ssh, __func__, r); 53 return 0; 54 } 55 56 int 57 dispatch_protocol_ignore(int type, u_int32_t seq, void *ssh) 58 { 59 logit("dispatch_protocol_ignore: type %d seq %u", type, seq); 60 return 0; 61 } 62 63 void 64 ssh_dispatch_init(struct ssh *ssh, dispatch_fn *dflt) 65 { 66 u_int i; 67 for (i = 0; i < DISPATCH_MAX; i++) 68 ssh->dispatch[i] = dflt; 69 } 70 71 void 72 ssh_dispatch_range(struct ssh *ssh, u_int from, u_int to, dispatch_fn *fn) 73 { 74 u_int i; 75 76 for (i = from; i <= to; i++) { 77 if (i >= DISPATCH_MAX) 78 break; 79 ssh->dispatch[i] = fn; 80 } 81 } 82 83 void 84 ssh_dispatch_set(struct ssh *ssh, int type, dispatch_fn *fn) 85 { 86 ssh->dispatch[type] = fn; 87 } 88 89 int 90 ssh_dispatch_run(struct ssh *ssh, int mode, volatile sig_atomic_t *done, 91 void *ctxt) 92 { 93 int r; 94 u_char type; 95 u_int32_t seqnr; 96 97 for (;;) { 98 if (mode == DISPATCH_BLOCK) { 99 r = ssh_packet_read_seqnr(ssh, &type, &seqnr); 100 if (r != 0) 101 return r; 102 } else { 103 r = ssh_packet_read_poll_seqnr(ssh, &type, &seqnr); 104 if (r != 0) 105 return r; 106 if (type == SSH_MSG_NONE) 107 return 0; 108 } 109 if (type > 0 && type < DISPATCH_MAX && 110 ssh->dispatch[type] != NULL) { 111 if (ssh->dispatch_skip_packets) { 112 debug2("skipped packet (type %u)", type); 113 ssh->dispatch_skip_packets--; 114 continue; 115 } 116 /* XXX 'ssh' will replace 'ctxt' later */ 117 r = (*ssh->dispatch[type])(type, seqnr, ctxt); 118 if (r != 0) 119 return r; 120 } else { 121 r = sshpkt_disconnect(ssh, 122 "protocol error: rcvd type %d", type); 123 if (r != 0) 124 return r; 125 return SSH_ERR_DISCONNECTED; 126 } 127 if (done != NULL && *done) 128 return 0; 129 } 130 } 131 132 void 133 ssh_dispatch_run_fatal(struct ssh *ssh, int mode, volatile sig_atomic_t *done, 134 void *ctxt) 135 { 136 int r; 137 138 if ((r = ssh_dispatch_run(ssh, mode, done, ctxt)) != 0) 139 sshpkt_fatal(ssh, __func__, r); 140 } 141