Fix handling of multiple SRV records for a single domain #10
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echoz.sh
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| srv="$( ( dig +short SRV "_xmpp-client._tcp.$domain" | grep . || echo "0 0 5222 $domain" ) | sort -n | sed 's/[[:digit:]]\+[[:space:]][[:digit:]]\+[[:space:]]//')" | ||
| host="$(echo "$srv" | sed 's/[[:digit:]]\+[[:space:]]//')" | ||
| srv="$( ( dig +short SRV "_xmpp-client._tcp.$domain" | grep . || echo "0 0 5222 $domain" ) | sort -n | sed -n '1s/[[:digit:]]\+[[:space:]][[:digit:]]\+[[:space:]]//p')" | ||
| host="$(echo "$srv" | sed 's/[[:digit:]]\+[[:space:]]//' | sed 's/\.$//')" |
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Why do you remove the trailing dot?
If there’s a good reason, it should be done in a single sed call anyways.
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While it certainly works even without removing the trailing dot, I get the following error message (seems benign though) on the first line (resulting from the invocation of openssl s_client):
$ ./echoz.sh [redacted]@xmpp.jp [redacted]
Can't use SSL_get_servername
depth=2 O = Digital Signature Trust Co., CN = DST Root CA X3
verify return:1
depth=1 C = US, O = Let's Encrypt, CN = Let's Encrypt Authority X3
verify return:1
depth=0 CN = xmpp.jp
verify return:1
Removing the trailing dot causes the error on the first line to go away. I can still have the script echo messages regardless of the error message.
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@RON42 My best guess is that the SRV record contains the domain name against which the TLS certificates are issued. That trailing dot somehow botches up s_client's checking of that. (Purely a hypothesis; I don't really have anything to back this).
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@horazont I would have changed that one sed call for $host to do that, but I haven't played with sed enough to know how to have the REGEX match something, skip over a certain amount upto the last character, and then match the last character, so that sed can discard that away.
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You can just separate the two s commands with a semicolon, like this:
sed 's/[[:digit:]]\+[[:space:]]//;s/\.$//'
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Thanks! Can you please address my question? Then we can get this merged quickly. |
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@horazont You're welcome. Actually, thank you, because I was looking for a low level way to read and send messages over XMPP, and now I can inspect the XML files (setting the script to debug mode, which you've very helpfully left in there) to know exactly that. |
Closes issue #9