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 "includes.h" 27 28 #include <sys/types.h> 29 30 #include <signal.h> 31 #include <stdarg.h> 32 33 #include "ssh1.h" 34 #include "ssh2.h" 35 #include "log.h" 36 #include "dispatch.h" 37 #include "packet.h" 38 #include "compat.h" 39 #include "ssherr.h" 40 41 int 42 dispatch_protocol_error(int type, u_int32_t seq, void *ctx) 43 { 44 struct ssh *ssh = active_state; /* XXX */ 45 int r; 46 47 logit("dispatch_protocol_error: type %d seq %u", type, seq); 48 if (!compat20) 49 fatal("protocol error"); 50 if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 || 51 (r = sshpkt_put_u32(ssh, seq)) != 0 || 52 (r = sshpkt_send(ssh)) != 0 || 53 (r = ssh_packet_write_wait(ssh)) != 0) 54 sshpkt_fatal(ssh, __func__, r); 55 return 0; 56 } 57 58 int 59 dispatch_protocol_ignore(int type, u_int32_t seq, void *ssh) 60 { 61 logit("dispatch_protocol_ignore: type %d seq %u", type, seq); 62 return 0; 63 } 64 65 void 66 ssh_dispatch_init(struct ssh *ssh, dispatch_fn *dflt) 67 { 68 u_int i; 69 for (i = 0; i < DISPATCH_MAX; i++) 70 ssh->dispatch[i] = dflt; 71 } 72 73 void 74 ssh_dispatch_range(struct ssh *ssh, u_int from, u_int to, dispatch_fn *fn) 75 { 76 u_int i; 77 78 for (i = from; i <= to; i++) { 79 if (i >= DISPATCH_MAX) 80 break; 81 ssh->dispatch[i] = fn; 82 } 83 } 84 85 void 86 ssh_dispatch_set(struct ssh *ssh, int type, dispatch_fn *fn) 87 { 88 ssh->dispatch[type] = fn; 89 } 90 91 int 92 ssh_dispatch_run(struct ssh *ssh, int mode, volatile sig_atomic_t *done, 93 void *ctxt) 94 { 95 int r; 96 u_char type; 97 u_int32_t seqnr; 98 99 for (;;) { 100 if (mode == DISPATCH_BLOCK) { 101 r = ssh_packet_read_seqnr(ssh, &type, &seqnr); 102 if (r != 0) 103 return r; 104 } else { 105 r = ssh_packet_read_poll_seqnr(ssh, &type, &seqnr); 106 if (r != 0) 107 return r; 108 if (type == SSH_MSG_NONE) 109 return 0; 110 } 111 if (type > 0 && type < DISPATCH_MAX && 112 ssh->dispatch[type] != NULL) { 113 if (ssh->dispatch_skip_packets) { 114 debug2("skipped packet (type %u)", type); 115 ssh->dispatch_skip_packets--; 116 continue; 117 } 118 /* XXX 'ssh' will replace 'ctxt' later */ 119 r = (*ssh->dispatch[type])(type, seqnr, ctxt); 120 if (r != 0) 121 return r; 122 } else { 123 r = sshpkt_disconnect(ssh, 124 "protocol error: rcvd type %d", type); 125 if (r != 0) 126 return r; 127 return SSH_ERR_DISCONNECTED; 128 } 129 if (done != NULL && *done) 130 return 0; 131 } 132 } 133 134 void 135 ssh_dispatch_run_fatal(struct ssh *ssh, int mode, volatile sig_atomic_t *done, 136 void *ctxt) 137 { 138 int r; 139 140 if ((r = ssh_dispatch_run(ssh, mode, done, ctxt)) != 0) 141 sshpkt_fatal(ssh, __func__, r); 142 } 143