diff options
Diffstat (limited to 'networking/ftpd.c')
| -rw-r--r-- | networking/ftpd.c | 65 |
1 files changed, 51 insertions, 14 deletions
diff --git a/networking/ftpd.c b/networking/ftpd.c index 6630db710..39a4d1869 100644 --- a/networking/ftpd.c +++ b/networking/ftpd.c @@ -972,23 +972,60 @@ cmdio_get_cmd_and_arg(void) free(G.ftp_cmd); len = 8 * 1024; /* Paranoia. Peer may send 1 gigabyte long cmd... */ - G.ftp_cmd = cmd = xmalloc_reads(STDIN_FILENO, NULL, &len); + G.ftp_cmd = cmd = xmalloc_fgets_str_len(stdin, "\r\n", &len); if (!cmd) exit(0); -/* TODO: de-escape telnet here: 0xff,0xff => 0xff */ -/* RFC959 says that ABOR, STAT, QUIT may be sent even during - * data transfer, and may be preceded by telnet's "Interrupt Process" - * code (two-byte sequence 255,244) and then by telnet "Synch" code - * 255,242 (byte 242 is sent with TCP URG bit using send(MSG_OOB) - * and may generate SIGURG on our side. See RFC854). - * So far we don't support that (may install SIGURG handler if we'd want to), - * but we need to at least remove 255,xxx pairs. lftp sends those. */ - - /* Trailing '\n' is already stripped, strip '\r' */ - len = strlen(cmd) - 1; - if ((ssize_t)len >= 0 && cmd[len] == '\r') - cmd[len--] = '\0'; + /* De-escape telnet: 0xff,0xff => 0xff */ + /* RFC959 says that ABOR, STAT, QUIT may be sent even during + * data transfer, and may be preceded by telnet's "Interrupt Process" + * code (two-byte sequence 255,244) and then by telnet "Synch" code + * 255,242 (byte 242 is sent with TCP URG bit using send(MSG_OOB) + * and may generate SIGURG on our side. See RFC854). + * So far we don't support that (may install SIGURG handler if we'd want to), + * but we need to at least remove 255,xxx pairs. lftp sends those. */ + /* Then de-escape FTP: NUL => '\n' */ + /* Testing for \xff: + * Create file named '\xff': echo Hello >`echo -ne "\xff"` + * Try to get it: ftpget -v 127.0.0.1 Eff `echo -ne "\xff\xff"` + * (need "\xff\xff" until ftpget applet is fixed to do escaping :) + * Testing for embedded LF: + * LF_HERE=`echo -ne "LF\nHERE"` + * echo Hello >"$LF_HERE" + * ftpget -v 127.0.0.1 LF_HERE "$LF_HERE" + */ + { + int dst, src; + + /* Strip "\r\n" if it is there */ + if (len != 0 && cmd[len - 1] == '\n') { + len--; + if (len != 0 && cmd[len - 1] == '\r') + len--; + cmd[len] = '\0'; + } + src = strchrnul(cmd, 0xff) - cmd; + /* 99,99% there are neither NULs nor 255s and src == len */ + if (src < len) { + dst = src; + do { + if ((unsigned char)(cmd[src]) == 255) { + src++; + /* 255,xxx - skip 255 */ + if ((unsigned char)(cmd[src]) != 255) { + /* 255,!255 - skip both */ + src++; + continue; + } + /* 255,255 - retain one 255 */ + } + /* NUL => '\n' */ + cmd[dst++] = cmd[src] ? cmd[src] : '\n'; + src++; + } while (src < len); + cmd[dst] = '\0'; + } + } if (G.verbose > 1) verbose_log(cmd); |