nchan.c revision 1.4
1#include "includes.h" 2RCSID("$Id: nchan.c,v 1.4 1999/10/25 21:03:17 markus Exp $"); 3 4#include "ssh.h" 5 6#include "buffer.h" 7#include "packet.h" 8#include "channels.h" 9#include "nchan.h" 10 11static void chan_send_ieof(Channel *c); 12static void chan_send_oclose(Channel *c); 13static void chan_shutdown_write(Channel *c); 14static void chan_shutdown_read(Channel *c); 15static void chan_delele_if_full_closed(Channel *c); 16 17/* 18 * EVENTS: update channel input/output states 19 * execute ACTIONS 20 */ 21/* events concerning the INPUT from socket for channel (istate) */ 22void 23chan_rcvd_oclose(Channel *c){ 24 switch(c->istate){ 25 case CHAN_INPUT_WAIT_OCLOSE: 26 debug("channel %d: INPUT_WAIT_OCLOSE -> INPUT_CLOSED [rcvd OCLOSE]", c->self); 27 c->istate=CHAN_INPUT_CLOSED; 28 chan_delele_if_full_closed(c); 29 break; 30 case CHAN_INPUT_OPEN: 31 debug("channel %d: INPUT_OPEN -> INPUT_CLOSED [rvcd OCLOSE, send IEOF]", c->self); 32 chan_shutdown_read(c); 33 chan_send_ieof(c); 34 c->istate=CHAN_INPUT_CLOSED; 35 chan_delele_if_full_closed(c); 36 break; 37 default: 38 debug("protocol error: chan_rcvd_oclose %d for istate %d",c->self,c->istate); 39 break; 40 } 41} 42void 43chan_read_failed(Channel *c){ 44 switch(c->istate){ 45 case CHAN_INPUT_OPEN: 46 debug("channel %d: INPUT_OPEN -> INPUT_WAIT_DRAIN [read failed]", c->self); 47 chan_shutdown_read(c); 48 c->istate=CHAN_INPUT_WAIT_DRAIN; 49 break; 50 default: 51 debug("internal error: we do not read, but chan_read_failed %d for istate %d", 52 c->self,c->istate); 53 break; 54 } 55} 56void 57chan_ibuf_empty(Channel *c){ 58 if(buffer_len(&c->input)){ 59 debug("internal error: chan_ibuf_empty %d for non empty buffer",c->self); 60 return; 61 } 62 switch(c->istate){ 63 case CHAN_INPUT_WAIT_DRAIN: 64 debug("channel %d: INPUT_WAIT_DRAIN -> INPUT_WAIT_OCLOSE [inbuf empty, send IEOF]", c->self); 65 chan_send_ieof(c); 66 c->istate=CHAN_INPUT_WAIT_OCLOSE; 67 break; 68 default: 69 debug("internal error: chan_ibuf_empty %d for istate %d",c->self,c->istate); 70 break; 71 } 72} 73/* events concerning the OUTPUT from channel for socket (ostate) */ 74void 75chan_rcvd_ieof(Channel *c){ 76 77 /* X11: if we receive IEOF for X11, then we have to FORCE sending of IEOF, 78 * this is from ssh-1.2.27 debugging output. 79 */ 80 if(c->x11){ 81 debug("channel %d: OUTPUT_OPEN -> OUTPUT_CLOSED/INPUT_WAIT_OCLOSED [X11 FIX]", c->self); 82 chan_send_ieof(c); 83 c->istate=CHAN_INPUT_WAIT_OCLOSE; 84 chan_send_oclose(c); 85 c->ostate=CHAN_OUTPUT_CLOSED; 86 chan_delele_if_full_closed(c); 87 return; 88 } 89 switch(c->ostate){ 90 case CHAN_OUTPUT_OPEN: 91 debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_DRAIN [rvcd IEOF]", c->self); 92 c->ostate=CHAN_OUTPUT_WAIT_DRAIN; 93 break; 94 case CHAN_OUTPUT_WAIT_IEOF: 95 debug("channel %d: OUTPUT_WAIT_IEOF -> OUTPUT_CLOSED [rvcd IEOF]", c->self); 96 c->ostate=CHAN_OUTPUT_CLOSED; 97 chan_delele_if_full_closed(c); 98 break; 99 default: 100 debug("protocol error: chan_rcvd_ieof %d for ostate %d", c->self,c->ostate); 101 break; 102 } 103} 104void 105chan_write_failed(Channel *c){ 106 switch(c->ostate){ 107 case CHAN_OUTPUT_OPEN: 108 debug("channel %d: OUTPUT_OPEN -> OUTPUT_WAIT_IEOF [write failed]", c->self); 109 chan_send_oclose(c); 110 c->ostate=CHAN_OUTPUT_WAIT_IEOF; 111 break; 112 case CHAN_OUTPUT_WAIT_DRAIN: 113 debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [write failed]", c->self); 114 chan_send_oclose(c); 115 c->ostate=CHAN_OUTPUT_CLOSED; 116 chan_delele_if_full_closed(c); 117 break; 118 default: 119 debug("internal error: chan_write_failed %d for ostate %d",c->self,c->ostate); 120 break; 121 } 122} 123void 124chan_obuf_empty(Channel *c){ 125 if(buffer_len(&c->output)){ 126 debug("internal error: chan_obuf_empty %d for non empty buffer",c->self); 127 return; 128 } 129 switch(c->ostate){ 130 case CHAN_OUTPUT_WAIT_DRAIN: 131 debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [obuf empty, send OCLOSE]", c->self); 132 chan_send_oclose(c); 133 c->ostate=CHAN_OUTPUT_CLOSED; 134 chan_delele_if_full_closed(c); 135 break; 136 default: 137 debug("internal error: chan_obuf_empty %d for ostate %d",c->self,c->ostate); 138 break; 139 } 140} 141/* 142 * ACTIONS: should never update c->istate or c->ostate 143 */ 144static void 145chan_send_ieof(Channel *c){ 146 switch(c->istate){ 147 case CHAN_INPUT_OPEN: 148 case CHAN_INPUT_WAIT_DRAIN: 149 packet_start(SSH_MSG_CHANNEL_INPUT_EOF); 150 packet_put_int(c->remote_id); 151 packet_send(); 152 break; 153 default: 154 debug("internal error: channel %d: cannot send IEOF for istate %d",c->self,c->istate); 155 break; 156 } 157} 158static void 159chan_send_oclose(Channel *c){ 160 switch(c->ostate){ 161 case CHAN_OUTPUT_OPEN: 162 case CHAN_OUTPUT_WAIT_DRAIN: 163 chan_shutdown_write(c); 164 buffer_consume(&c->output, buffer_len(&c->output)); 165 packet_start(SSH_MSG_CHANNEL_OUTPUT_CLOSE); 166 packet_put_int(c->remote_id); 167 packet_send(); 168 break; 169 default: 170 debug("internal error: channel %d: cannot send OCLOSE for ostate %d",c->self,c->istate); 171 break; 172 } 173} 174/* helper */ 175static void 176chan_shutdown_write(Channel *c){ 177 debug("channel %d: shutdown_write", c->self); 178 if(shutdown(c->sock, SHUT_WR)<0) 179 error("chan_shutdown_write failed for #%d/fd%d: %.100s", 180 c->self, c->sock, strerror(errno)); 181} 182static void 183chan_shutdown_read(Channel *c){ 184 debug("channel %d: shutdown_read", c->self); 185 if(shutdown(c->sock, SHUT_RD)<0) 186 error("chan_shutdown_read failed for #%d/fd%d: %.100s", 187 c->self, c->sock, strerror(errno)); 188} 189static void 190chan_delele_if_full_closed(Channel *c){ 191 if(c->istate==CHAN_INPUT_CLOSED && c->ostate==CHAN_OUTPUT_CLOSED){ 192 debug("channel %d: closing", c->self); 193 channel_free(c->self); 194 } 195} 196void 197chan_init_iostates(Channel *c){ 198 c->ostate=CHAN_OUTPUT_OPEN; 199 c->istate=CHAN_INPUT_OPEN; 200} 201