How do I make use of SSLSetALPNProtocols?

Question

I'm working on a TLS library for the vapor project and am supporting both Apple's (Transport-)Security and OpenSSL for use in an HTTP/2 client and server.

On this line of code I'm trying to call SSLSetALPNProtocols. Regardless of my approach, I'm met with an ld linker error on that line of code.

Undefined symbols for architecture x86_64:
  "_SSLSetALPNProtocols", referenced from:
      __T08AppleSSL9SSLOptionV4alpnACSaySSG9protocols_tFZySo10SSLContextCKcfU_ in Options.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

There's no documentation available to highlight a possible obvious mistake since the page is empty.

So, how do I get this code to compile with ALPN support?

score 2 · Answer 1 · answered Nov 03 '17 at 20:30

2

Currently that's impossible. Apple forgot to export the SSLSetALPNProtocols and SSLCopyALPNProtocols function.

I already filed rdar://34790589 (duplicate of rdar://33907676)

answered Nov 03 '17 at 20:30

ePirat

1,068
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I also filed an rdar and indeed recently found out this was a known issue. – JoannisO Nov 04 '17 at 19:39

score -1 · Accepted Answer · answered Jan 28 '18 at 11:17

-1

As of the latest macOS and Xcode beta with Swift 4.1 I've got this up and running.

answered Jan 28 '18 at 11:17

JoannisO

875
7
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This is not an answer to your question, you should not accept it. – Ad N Aug 01 '19 at 08:51
There was a radar open that apple fixed and I posted an answer myself to indicate this. Would you rather see me keep this issue open indefinitely even though it should be resolved by apple now? – JoannisO Aug 02 '19 at 09:42

How do I make use of SSLSetALPNProtocols?

2 Answers2