[821] | 1 | /* vi: set sw=4 ts=4: */
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| 2 | /*
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| 3 | * Simple telnet server
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| 4 | * Bjorn Wesen, Axis Communications AB (bjornw@axis.com)
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| 5 | *
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| 6 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
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| 7 | *
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| 8 | * ---------------------------------------------------------------------------
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| 9 | * (C) Copyright 2000, Axis Communications AB, LUND, SWEDEN
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| 10 | ****************************************************************************
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| 11 | *
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| 12 | * The telnetd manpage says it all:
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| 13 | *
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| 14 | * Telnetd operates by allocating a pseudo-terminal device (see pty(4)) for
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| 15 | * a client, then creating a login process which has the slave side of the
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| 16 | * pseudo-terminal as stdin, stdout, and stderr. Telnetd manipulates the
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| 17 | * master side of the pseudo-terminal, implementing the telnet protocol and
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| 18 | * passing characters between the remote client and the login process.
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| 19 | *
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| 20 | * Vladimir Oleynik <dzo@simtreas.ru> 2001
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| 21 | * Set process group corrections, initial busybox port
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| 22 | */
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| 23 |
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[1770] | 24 | #define DEBUG 0
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[821] | 25 |
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[1770] | 26 | #include "libbb.h"
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| 27 |
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| 28 | #if DEBUG
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[821] | 29 | #define TELCMDS
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| 30 | #define TELOPTS
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| 31 | #endif
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| 32 | #include <arpa/telnet.h>
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| 33 | #include <sys/syslog.h>
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| 34 |
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| 35 |
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[1770] | 36 | #if ENABLE_LOGIN
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| 37 | static const char *loginpath = "/bin/login";
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[821] | 38 | #else
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[1770] | 39 | static const char *loginpath = DEFAULT_SHELL;
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[821] | 40 | #endif
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| 41 |
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| 42 | static const char *issuefile = "/etc/issue.net";
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| 43 |
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| 44 | /* structure that describes a session */
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| 45 |
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| 46 | struct tsession {
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[1770] | 47 | struct tsession *next;
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[821] | 48 | int sockfd_read, sockfd_write, ptyfd;
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| 49 | int shell_pid;
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| 50 | /* two circular buffers */
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| 51 | char *buf1, *buf2;
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| 52 | int rdidx1, wridx1, size1;
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| 53 | int rdidx2, wridx2, size2;
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| 54 | };
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| 55 |
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[1770] | 56 | /* Two buffers are directly after tsession in malloced memory.
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| 57 | * Make whole thing fit in 4k */
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| 58 | enum { BUFSIZE = (4*1024 - sizeof(struct tsession)) / 2 };
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| 59 |
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[821] | 60 | /*
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| 61 | This is how the buffers are used. The arrows indicate the movement
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| 62 | of data.
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| 63 |
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| 64 | +-------+ wridx1++ +------+ rdidx1++ +----------+
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| 65 | | | <-------------- | buf1 | <-------------- | |
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| 66 | | | size1-- +------+ size1++ | |
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| 67 | | pty | | socket |
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| 68 | | | rdidx2++ +------+ wridx2++ | |
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| 69 | | | --------------> | buf2 | --------------> | |
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| 70 | +-------+ size2++ +------+ size2-- +----------+
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| 71 |
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| 72 | Each session has got two buffers.
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| 73 | */
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| 74 |
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| 75 | static int maxfd;
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| 76 |
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| 77 | static struct tsession *sessions;
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| 78 |
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| 79 |
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| 80 | /*
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| 81 | Remove all IAC's from the buffer pointed to by bf (received IACs are ignored
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| 82 | and must be removed so as to not be interpreted by the terminal). Make an
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| 83 | uninterrupted string of characters fit for the terminal. Do this by packing
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| 84 | all characters meant for the terminal sequentially towards the end of bf.
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| 85 |
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| 86 | Return a pointer to the beginning of the characters meant for the terminal.
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| 87 | and make *num_totty the number of characters that should be sent to
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| 88 | the terminal.
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| 89 |
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| 90 | Note - If an IAC (3 byte quantity) starts before (bf + len) but extends
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| 91 | past (bf + len) then that IAC will be left unprocessed and *processed will be
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| 92 | less than len.
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| 93 |
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| 94 | FIXME - if we mean to send 0xFF to the terminal then it will be escaped,
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| 95 | what is the escape character? We aren't handling that situation here.
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| 96 |
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| 97 | CR-LF ->'s CR mapping is also done here, for convenience
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[1770] | 98 | */
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[821] | 99 | static char *
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[1770] | 100 | remove_iacs(struct tsession *ts, int *pnum_totty)
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| 101 | {
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[821] | 102 | unsigned char *ptr0 = (unsigned char *)ts->buf1 + ts->wridx1;
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| 103 | unsigned char *ptr = ptr0;
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| 104 | unsigned char *totty = ptr;
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| 105 | unsigned char *end = ptr + MIN(BUFSIZE - ts->wridx1, ts->size1);
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| 106 | int processed;
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| 107 | int num_totty;
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| 108 |
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| 109 | while (ptr < end) {
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| 110 | if (*ptr != IAC) {
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| 111 | int c = *ptr;
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| 112 | *totty++ = *ptr++;
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| 113 | /* We now map \r\n ==> \r for pragmatic reasons.
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| 114 | * Many client implementations send \r\n when
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| 115 | * the user hits the CarriageReturn key.
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| 116 | */
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| 117 | if (c == '\r' && (*ptr == '\n' || *ptr == 0) && ptr < end)
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| 118 | ptr++;
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[1770] | 119 | } else {
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[821] | 120 | /*
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| 121 | * TELOPT_NAWS support!
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| 122 | */
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| 123 | if ((ptr+2) >= end) {
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| 124 | /* only the beginning of the IAC is in the
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| 125 | buffer we were asked to process, we can't
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| 126 | process this char. */
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| 127 | break;
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| 128 | }
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| 129 |
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| 130 | /*
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| 131 | * IAC -> SB -> TELOPT_NAWS -> 4-byte -> IAC -> SE
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| 132 | */
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| 133 | else if (ptr[1] == SB && ptr[2] == TELOPT_NAWS) {
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| 134 | struct winsize ws;
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| 135 | if ((ptr+8) >= end)
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| 136 | break; /* incomplete, can't process */
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| 137 | ws.ws_col = (ptr[3] << 8) | ptr[4];
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| 138 | ws.ws_row = (ptr[5] << 8) | ptr[6];
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[1770] | 139 | ioctl(ts->ptyfd, TIOCSWINSZ, (char *)&ws);
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[821] | 140 | ptr += 9;
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[1770] | 141 | } else {
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[821] | 142 | /* skip 3-byte IAC non-SB cmd */
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[1770] | 143 | #if DEBUG
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[821] | 144 | fprintf(stderr, "Ignoring IAC %s,%s\n",
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[1770] | 145 | TELCMD(ptr[1]), TELOPT(ptr[2]));
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[821] | 146 | #endif
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| 147 | ptr += 3;
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| 148 | }
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| 149 | }
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| 150 | }
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| 151 |
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| 152 | processed = ptr - ptr0;
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| 153 | num_totty = totty - ptr0;
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| 154 | /* the difference between processed and num_to tty
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| 155 | is all the iacs we removed from the stream.
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| 156 | Adjust buf1 accordingly. */
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| 157 | ts->wridx1 += processed - num_totty;
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| 158 | ts->size1 -= processed - num_totty;
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| 159 | *pnum_totty = num_totty;
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| 160 | /* move the chars meant for the terminal towards the end of the
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| 161 | buffer. */
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| 162 | return memmove(ptr - num_totty, ptr0, num_totty);
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| 163 | }
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| 164 |
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| 165 |
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| 166 | static int
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[1770] | 167 | getpty(char *line, int size)
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[821] | 168 | {
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| 169 | int p;
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[1770] | 170 | #if ENABLE_FEATURE_DEVPTS
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| 171 | p = open("/dev/ptmx", O_RDWR);
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[821] | 172 | if (p > 0) {
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[1770] | 173 | const char *name;
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[821] | 174 | grantpt(p);
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| 175 | unlockpt(p);
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[1770] | 176 | name = ptsname(p);
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| 177 | if (!name) {
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| 178 | bb_perror_msg("ptsname error (is /dev/pts mounted?)");
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| 179 | return -1;
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| 180 | }
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| 181 | safe_strncpy(line, name, size);
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| 182 | return p;
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[821] | 183 | }
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| 184 | #else
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| 185 | struct stat stb;
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| 186 | int i;
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| 187 | int j;
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| 188 |
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| 189 | strcpy(line, "/dev/ptyXX");
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| 190 |
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| 191 | for (i = 0; i < 16; i++) {
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| 192 | line[8] = "pqrstuvwxyzabcde"[i];
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| 193 | line[9] = '0';
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| 194 | if (stat(line, &stb) < 0) {
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| 195 | continue;
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| 196 | }
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| 197 | for (j = 0; j < 16; j++) {
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| 198 | line[9] = j < 10 ? j + '0' : j - 10 + 'a';
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[1770] | 199 | if (DEBUG)
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| 200 | fprintf(stderr, "Trying to open device: %s\n", line);
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| 201 | p = open(line, O_RDWR | O_NOCTTY);
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| 202 | if (p >= 0) {
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[821] | 203 | line[5] = 't';
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| 204 | return p;
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| 205 | }
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| 206 | }
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| 207 | }
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[1770] | 208 | #endif /* FEATURE_DEVPTS */
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[821] | 209 | return -1;
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| 210 | }
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| 211 |
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| 212 |
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| 213 | static void
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| 214 | send_iac(struct tsession *ts, unsigned char command, int option)
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| 215 | {
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[1770] | 216 | /* We rely on that there is space in the buffer for now. */
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[821] | 217 | char *b = ts->buf2 + ts->rdidx2;
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| 218 | *b++ = IAC;
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| 219 | *b++ = command;
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| 220 | *b++ = option;
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| 221 | ts->rdidx2 += 3;
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| 222 | ts->size2 += 3;
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| 223 | }
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| 224 |
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| 225 |
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| 226 | static struct tsession *
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[1770] | 227 | make_new_session(
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| 228 | USE_FEATURE_TELNETD_STANDALONE(int sock_r, int sock_w)
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| 229 | SKIP_FEATURE_TELNETD_STANDALONE(void)
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| 230 | ) {
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| 231 | const char *login_argv[2];
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[821] | 232 | struct termios termbuf;
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[1770] | 233 | int fd, pid;
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[821] | 234 | char tty_name[32];
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| 235 | struct tsession *ts = xzalloc(sizeof(struct tsession) + BUFSIZE * 2);
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| 236 |
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| 237 | ts->buf1 = (char *)(&ts[1]);
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| 238 | ts->buf2 = ts->buf1 + BUFSIZE;
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| 239 |
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[1770] | 240 | /* Got a new connection, set up a tty. */
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| 241 | fd = getpty(tty_name, 32);
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| 242 | if (fd < 0) {
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| 243 | bb_error_msg("all terminals in use");
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| 244 | return NULL;
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| 245 | }
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| 246 | if (fd > maxfd) maxfd = fd;
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| 247 | ndelay_on(ts->ptyfd = fd);
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| 248 | #if ENABLE_FEATURE_TELNETD_STANDALONE
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| 249 | if (sock_w > maxfd) maxfd = sock_w;
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| 250 | if (sock_r > maxfd) maxfd = sock_r;
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| 251 | ndelay_on(ts->sockfd_write = sock_w);
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| 252 | ndelay_on(ts->sockfd_read = sock_r);
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| 253 | #else
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[821] | 254 | ts->sockfd_write = 1;
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[1770] | 255 | /* xzalloc: ts->sockfd_read = 0; */
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| 256 | ndelay_on(0);
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| 257 | ndelay_on(1);
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| 258 | #endif
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[821] | 259 | /* Make the telnet client understand we will echo characters so it
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| 260 | * should not do it locally. We don't tell the client to run linemode,
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| 261 | * because we want to handle line editing and tab completion and other
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[1770] | 262 | * stuff that requires char-by-char support. */
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[821] | 263 | send_iac(ts, DO, TELOPT_ECHO);
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| 264 | send_iac(ts, DO, TELOPT_NAWS);
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| 265 | send_iac(ts, DO, TELOPT_LFLOW);
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| 266 | send_iac(ts, WILL, TELOPT_ECHO);
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| 267 | send_iac(ts, WILL, TELOPT_SGA);
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| 268 |
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[1770] | 269 | pid = fork();
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| 270 | if (pid < 0) {
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| 271 | free(ts);
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| 272 | close(fd);
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| 273 | bb_perror_msg("fork");
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| 274 | return NULL;
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[821] | 275 | }
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[1770] | 276 | if (pid > 0) {
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| 277 | /* parent */
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| 278 | ts->shell_pid = pid;
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| 279 | return ts;
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| 280 | }
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[821] | 281 |
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[1770] | 282 | /* child */
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[821] | 283 |
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[1770] | 284 | /* make new session and process group */
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| 285 | setsid();
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[821] | 286 |
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[1770] | 287 | /* open the child's side of the tty. */
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| 288 | /* NB: setsid() disconnects from any previous ctty's. Therefore
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| 289 | * we must open child's side of the tty AFTER setsid! */
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| 290 | fd = xopen(tty_name, O_RDWR); /* becomes our ctty */
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| 291 | dup2(fd, 0);
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| 292 | dup2(fd, 1);
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| 293 | dup2(fd, 2);
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| 294 | while (fd > 2) close(fd--);
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| 295 | tcsetpgrp(0, getpid()); /* switch this tty's process group to us */
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[821] | 296 |
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[1770] | 297 | /* The pseudo-terminal allocated to the client is configured to operate in
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| 298 | * cooked mode, and with XTABS CRMOD enabled (see tty(4)). */
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| 299 | tcgetattr(0, &termbuf);
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| 300 | termbuf.c_lflag |= ECHO; /* if we use readline we dont want this */
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| 301 | termbuf.c_oflag |= ONLCR|XTABS;
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| 302 | termbuf.c_iflag |= ICRNL;
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| 303 | termbuf.c_iflag &= ~IXOFF;
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| 304 | /*termbuf.c_lflag &= ~ICANON;*/
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| 305 | tcsetattr(0, TCSANOW, &termbuf);
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[821] | 306 |
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[1770] | 307 | print_login_issue(issuefile, NULL);
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[821] | 308 |
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[1770] | 309 | /* exec shell / login /whatever */
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| 310 | login_argv[0] = loginpath;
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| 311 | login_argv[1] = NULL;
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| 312 | execv(loginpath, (char **)login_argv);
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| 313 | /* Hmmm... this gets sent to the client thru fd#2! Is it ok?? */
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| 314 | bb_perror_msg_and_die("execv %s", loginpath);
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| 315 | }
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[821] | 316 |
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[1770] | 317 | #if ENABLE_FEATURE_TELNETD_STANDALONE
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[821] | 318 |
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| 319 | static void
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| 320 | free_session(struct tsession *ts)
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| 321 | {
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| 322 | struct tsession *t = sessions;
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| 323 |
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[1770] | 324 | /* unlink this telnet session from the session list */
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[821] | 325 | if (t == ts)
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| 326 | sessions = ts->next;
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| 327 | else {
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[1770] | 328 | while (t->next != ts)
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[821] | 329 | t = t->next;
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| 330 | t->next = ts->next;
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| 331 | }
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| 332 |
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| 333 | kill(ts->shell_pid, SIGKILL);
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| 334 | wait4(ts->shell_pid, NULL, 0, NULL);
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| 335 | close(ts->ptyfd);
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[1770] | 336 | close(ts->sockfd_read);
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| 337 | /* error if ts->sockfd_read == ts->sockfd_write. So what? ;) */
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| 338 | close(ts->sockfd_write);
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[821] | 339 | free(ts);
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| 340 |
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[1770] | 341 | /* scan all sessions and find new maxfd */
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| 342 | ts = sessions;
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| 343 | maxfd = 0;
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| 344 | while (ts) {
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| 345 | if (maxfd < ts->ptyfd)
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| 346 | maxfd = ts->ptyfd;
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| 347 | if (maxfd < ts->sockfd_read)
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| 348 | maxfd = ts->sockfd_read;
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| 349 | if (maxfd < ts->sockfd_write)
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| 350 | maxfd = ts->sockfd_write;
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| 351 | ts = ts->next;
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[821] | 352 | }
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[1770] | 353 | }
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[821] | 354 |
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[1770] | 355 | #else /* !FEATURE_TELNETD_STANDALONE */
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[821] | 356 |
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[1770] | 357 | /* Never actually called */
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| 358 | void free_session(struct tsession *ts);
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[821] | 359 |
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[1770] | 360 | #endif
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[821] | 361 |
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| 362 |
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[1770] | 363 | int telnetd_main(int argc, char **argv);
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| 364 | int telnetd_main(int argc, char **argv)
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| 365 | {
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| 366 | fd_set rdfdset, wrfdset;
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| 367 | unsigned opt;
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| 368 | int selret, maxlen, w, r;
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| 369 | struct tsession *ts;
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| 370 | #if ENABLE_FEATURE_TELNETD_STANDALONE
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| 371 | #define IS_INETD (opt & OPT_INETD)
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| 372 | int master_fd = -1; /* be happy, gcc */
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| 373 | unsigned portnbr = 23;
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| 374 | char *opt_bindaddr = NULL;
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| 375 | char *opt_portnbr;
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| 376 | #else
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| 377 | enum {
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| 378 | IS_INETD = 1,
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| 379 | master_fd = -1,
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| 380 | portnbr = 23,
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| 381 | };
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| 382 | #endif
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| 383 | enum {
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| 384 | OPT_PORT = 4 * ENABLE_FEATURE_TELNETD_STANDALONE,
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| 385 | OPT_FOREGROUND = 0x10 * ENABLE_FEATURE_TELNETD_STANDALONE,
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| 386 | OPT_INETD = 0x20 * ENABLE_FEATURE_TELNETD_STANDALONE,
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| 387 | };
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[821] | 388 |
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[1770] | 389 | opt = getopt32(argv, "f:l:" USE_FEATURE_TELNETD_STANDALONE("p:b:Fi"),
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| 390 | &issuefile, &loginpath
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| 391 | USE_FEATURE_TELNETD_STANDALONE(, &opt_portnbr, &opt_bindaddr));
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| 392 | /* Redirect log to syslog early, if needed */
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| 393 | if (IS_INETD || !(opt & OPT_FOREGROUND)) {
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| 394 | openlog(applet_name, 0, LOG_USER);
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| 395 | logmode = LOGMODE_SYSLOG;
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| 396 | }
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| 397 | //if (opt & 1) // -f
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| 398 | //if (opt & 2) // -l
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| 399 | USE_FEATURE_TELNETD_STANDALONE(
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| 400 | if (opt & OPT_PORT) // -p
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| 401 | portnbr = xatou16(opt_portnbr);
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| 402 | //if (opt & 8) // -b
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| 403 | //if (opt & 0x10) // -F
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| 404 | //if (opt & 0x20) // -i
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| 405 | );
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[821] | 406 |
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[1770] | 407 | /* Used to check access(loginpath, X_OK) here. Pointless.
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| 408 | * exec will do this for us for free later. */
|
---|
[821] | 409 |
|
---|
[1770] | 410 | #if ENABLE_FEATURE_TELNETD_STANDALONE
|
---|
| 411 | if (IS_INETD) {
|
---|
| 412 | sessions = make_new_session(0, 1);
|
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| 413 | } else {
|
---|
| 414 | master_fd = create_and_bind_stream_or_die(opt_bindaddr, portnbr);
|
---|
| 415 | xlisten(master_fd, 1);
|
---|
| 416 | if (!(opt & OPT_FOREGROUND))
|
---|
| 417 | bb_daemonize(DAEMON_CHDIR_ROOT);
|
---|
| 418 | }
|
---|
[821] | 419 | #else
|
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[1770] | 420 | sessions = make_new_session();
|
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[821] | 421 | #endif
|
---|
| 422 |
|
---|
[1770] | 423 | /* We don't want to die if just one session is broken */
|
---|
| 424 | signal(SIGPIPE, SIG_IGN);
|
---|
[821] | 425 |
|
---|
[1770] | 426 | again:
|
---|
| 427 | FD_ZERO(&rdfdset);
|
---|
| 428 | FD_ZERO(&wrfdset);
|
---|
| 429 | if (!IS_INETD) {
|
---|
| 430 | FD_SET(master_fd, &rdfdset);
|
---|
| 431 | /* This is needed because free_session() does not
|
---|
| 432 | * take into account master_fd when it finds new
|
---|
| 433 | * maxfd among remaining fd's: */
|
---|
| 434 | if (master_fd > maxfd)
|
---|
| 435 | maxfd = master_fd;
|
---|
| 436 | }
|
---|
[821] | 437 |
|
---|
[1770] | 438 | /* select on the master socket, all telnet sockets and their
|
---|
| 439 | * ptys if there is room in their session buffers. */
|
---|
| 440 | ts = sessions;
|
---|
| 441 | while (ts) {
|
---|
| 442 | /* buf1 is used from socket to pty
|
---|
| 443 | * buf2 is used from pty to socket */
|
---|
| 444 | if (ts->size1 > 0) /* can write to pty */
|
---|
| 445 | FD_SET(ts->ptyfd, &wrfdset);
|
---|
| 446 | if (ts->size1 < BUFSIZE) /* can read from socket */
|
---|
| 447 | FD_SET(ts->sockfd_read, &rdfdset);
|
---|
| 448 | if (ts->size2 > 0) /* can write to socket */
|
---|
| 449 | FD_SET(ts->sockfd_write, &wrfdset);
|
---|
| 450 | if (ts->size2 < BUFSIZE) /* can read from pty */
|
---|
| 451 | FD_SET(ts->ptyfd, &rdfdset);
|
---|
| 452 | ts = ts->next;
|
---|
| 453 | }
|
---|
[821] | 454 |
|
---|
[1770] | 455 | selret = select(maxfd + 1, &rdfdset, &wrfdset, 0, 0);
|
---|
| 456 | if (!selret)
|
---|
| 457 | return 0;
|
---|
[821] | 458 |
|
---|
[1770] | 459 | #if ENABLE_FEATURE_TELNETD_STANDALONE
|
---|
| 460 | /* First check for and accept new sessions. */
|
---|
| 461 | if (!IS_INETD && FD_ISSET(master_fd, &rdfdset)) {
|
---|
| 462 | int fd;
|
---|
| 463 | struct tsession *new_ts;
|
---|
[821] | 464 |
|
---|
[1770] | 465 | fd = accept(master_fd, NULL, 0);
|
---|
| 466 | if (fd < 0)
|
---|
| 467 | goto again;
|
---|
| 468 | /* Create a new session and link it into our active list */
|
---|
| 469 | new_ts = make_new_session(fd, fd);
|
---|
| 470 | if (new_ts) {
|
---|
| 471 | new_ts->next = sessions;
|
---|
| 472 | sessions = new_ts;
|
---|
| 473 | } else {
|
---|
| 474 | close(fd);
|
---|
[821] | 475 | }
|
---|
[1770] | 476 | }
|
---|
| 477 | #endif
|
---|
[821] | 478 |
|
---|
[1770] | 479 | /* Then check for data tunneling. */
|
---|
| 480 | ts = sessions;
|
---|
| 481 | while (ts) { /* For all sessions... */
|
---|
| 482 | struct tsession *next = ts->next; /* in case we free ts. */
|
---|
[821] | 483 |
|
---|
[1770] | 484 | if (ts->size1 && FD_ISSET(ts->ptyfd, &wrfdset)) {
|
---|
| 485 | int num_totty;
|
---|
| 486 | char *ptr;
|
---|
| 487 | /* Write to pty from buffer 1. */
|
---|
| 488 | ptr = remove_iacs(ts, &num_totty);
|
---|
| 489 | w = safe_write(ts->ptyfd, ptr, num_totty);
|
---|
| 490 | /* needed? if (w < 0 && errno == EAGAIN) continue; */
|
---|
| 491 | if (w < 0) {
|
---|
| 492 | if (IS_INETD)
|
---|
| 493 | return 0;
|
---|
| 494 | free_session(ts);
|
---|
| 495 | ts = next;
|
---|
[821] | 496 | continue;
|
---|
| 497 | }
|
---|
[1770] | 498 | ts->wridx1 += w;
|
---|
| 499 | ts->size1 -= w;
|
---|
| 500 | if (ts->wridx1 == BUFSIZE)
|
---|
| 501 | ts->wridx1 = 0;
|
---|
[821] | 502 | }
|
---|
| 503 |
|
---|
[1770] | 504 | if (ts->size2 && FD_ISSET(ts->sockfd_write, &wrfdset)) {
|
---|
| 505 | /* Write to socket from buffer 2. */
|
---|
| 506 | maxlen = MIN(BUFSIZE - ts->wridx2, ts->size2);
|
---|
| 507 | w = safe_write(ts->sockfd_write, ts->buf2 + ts->wridx2, maxlen);
|
---|
| 508 | /* needed? if (w < 0 && errno == EAGAIN) continue; */
|
---|
| 509 | if (w < 0) {
|
---|
| 510 | if (IS_INETD)
|
---|
| 511 | return 0;
|
---|
| 512 | free_session(ts);
|
---|
| 513 | ts = next;
|
---|
| 514 | continue;
|
---|
[821] | 515 | }
|
---|
[1770] | 516 | ts->wridx2 += w;
|
---|
| 517 | ts->size2 -= w;
|
---|
| 518 | if (ts->wridx2 == BUFSIZE)
|
---|
| 519 | ts->wridx2 = 0;
|
---|
| 520 | }
|
---|
[821] | 521 |
|
---|
[1770] | 522 | if (ts->size1 < BUFSIZE && FD_ISSET(ts->sockfd_read, &rdfdset)) {
|
---|
| 523 | /* Read from socket to buffer 1. */
|
---|
| 524 | maxlen = MIN(BUFSIZE - ts->rdidx1, BUFSIZE - ts->size1);
|
---|
| 525 | r = safe_read(ts->sockfd_read, ts->buf1 + ts->rdidx1, maxlen);
|
---|
| 526 | if (r < 0 && errno == EAGAIN) continue;
|
---|
| 527 | if (r <= 0) {
|
---|
| 528 | if (IS_INETD)
|
---|
| 529 | return 0;
|
---|
| 530 | free_session(ts);
|
---|
| 531 | ts = next;
|
---|
| 532 | continue;
|
---|
[821] | 533 | }
|
---|
[1770] | 534 | if (!ts->buf1[ts->rdidx1 + r - 1])
|
---|
| 535 | if (!--r)
|
---|
[821] | 536 | continue;
|
---|
[1770] | 537 | ts->rdidx1 += r;
|
---|
| 538 | ts->size1 += r;
|
---|
| 539 | if (ts->rdidx1 == BUFSIZE)
|
---|
| 540 | ts->rdidx1 = 0;
|
---|
| 541 | }
|
---|
[821] | 542 |
|
---|
[1770] | 543 | if (ts->size2 < BUFSIZE && FD_ISSET(ts->ptyfd, &rdfdset)) {
|
---|
| 544 | /* Read from pty to buffer 2. */
|
---|
| 545 | maxlen = MIN(BUFSIZE - ts->rdidx2, BUFSIZE - ts->size2);
|
---|
| 546 | r = safe_read(ts->ptyfd, ts->buf2 + ts->rdidx2, maxlen);
|
---|
| 547 | if (r < 0 && errno == EAGAIN) continue;
|
---|
| 548 | if (r <= 0) {
|
---|
| 549 | if (IS_INETD)
|
---|
| 550 | return 0;
|
---|
| 551 | free_session(ts);
|
---|
| 552 | ts = next;
|
---|
| 553 | continue;
|
---|
[821] | 554 | }
|
---|
[1770] | 555 | ts->rdidx2 += r;
|
---|
| 556 | ts->size2 += r;
|
---|
| 557 | if (ts->rdidx2 == BUFSIZE)
|
---|
[821] | 558 | ts->rdidx2 = 0;
|
---|
| 559 | }
|
---|
| 560 |
|
---|
[1770] | 561 | if (ts->size1 == 0) {
|
---|
| 562 | ts->rdidx1 = 0;
|
---|
| 563 | ts->wridx1 = 0;
|
---|
| 564 | }
|
---|
| 565 | if (ts->size2 == 0) {
|
---|
| 566 | ts->rdidx2 = 0;
|
---|
| 567 | ts->wridx2 = 0;
|
---|
| 568 | }
|
---|
| 569 | ts = next;
|
---|
| 570 | }
|
---|
| 571 | goto again;
|
---|
[821] | 572 | }
|
---|