Mercurial > dropbear
annotate SMALL @ 135:d663445c1533
Initialise the outgoing packet queue
author | Matt Johnston <matt@ucc.asn.au> |
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date | Wed, 03 Nov 2004 13:47:44 +0000 |
parents | fe6bca95afa7 |
children | b9d3f725e00b |
rev | line source |
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1 Tips for a small system: |
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2 |
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3 The following are set in options.h |
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4 |
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5 - You can safely disable blowfish and twofish ciphers, and MD5 hmac, without |
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6 affecting interoperability |
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7 |
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8 - If you're compiling statically, you can turn off host lookups |
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9 |
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10 - You can disable either password or public-key authentication, though note |
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11 that the IETF draft states that pubkey authentication is required. |
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12 |
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13 - Similarly with DSS and RSA, you can disable one of these if you know that |
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14 all clients will be able to support a particular one. The IETF draft |
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15 states that DSS is required, however you may prefer to use RSA. |
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16 DON'T disable either of these on systems where you aren't 100% sure about |
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17 who will be connecting and what clients they will be using. |
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18 |
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19 - Disabling the MOTD code and SFTP-SERVER may save a small amount of codesize |
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20 |
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21 - You can disable x11, tcp and agent forwarding as desired. None of these are |
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22 essential, although agent-forwarding is often useful even on firewall boxes. |
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23 |
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24 If you are compiling statically, you may want to disable zlib, as it will use |
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25 a few tens of kB of binary-size (./configure --disable-zlib). |
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26 |
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27 You can create a combined binary, see the file MULTI, which will put all |
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28 the functions into one binary, avoiding repeated code. |
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29 |
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30 If you're compiling with gcc, you might want to look at gcc's options for |
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31 stripping unused code. The relevant vars to set before configure are: |
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32 |
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33 LDFLAGS=-Wl,--gc-sections |
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34 CFLAGS="-ffunction-sections -fdata-sections" |
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35 |
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36 You can also experiment with optimisation flags such as -Os, note that in some |
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37 cases these flags actually seem to increase size, so experiment before |
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38 deciding. |
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39 |
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40 Of course using small C libraries such as uClibc and dietlibc can also help. |
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41 |
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42 If you have any queries, mail me and I'll see if I can help. |