Ziti_resolve faults if host is NULL

[tomc797]

The fix addresses a Ziti_resolve defects that triggers segfault. The getaddrinfo interface contract permits host == NULL, but Ziti_resolve assumes host != NULL. Additionally, Ziti_resolve leaks res and addr if error is signaled.

ubuntu@jammy:~$ zitify -i tomc.json -b 9999:zitify-nc-service nc -l 9999
b = 9999:zitify-nc-service
bindings = 
/usr/local/bin/zitify: line 101: 457642 Segmentation fault      (core dumped) LD_PRELOAD="$preload_lib" ZITI_BINDINGS="${bindings}" "$@"
ubuntu@jammy:~$ zitify -i tomc.json -b 9999:zitify-nc-service gdb nc
b = 9999:zitify-nc-service
bindings = 
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Reading symbols from nc...
(No debugging symbols found in nc)
(gdb) r -l 9999
Starting program: /usr/bin/nc -l 9999
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7ffff73ff640 (LWP 457774)]
[New Thread 0x7ffff6bfe640 (LWP 457775)]
[New Thread 0x7ffff63fd640 (LWP 457776)]
[New Thread 0x7ffff5bfc640 (LWP 457777)]
[New Thread 0x7ffff53fb640 (LWP 457778)]

Thread 1 "nc" received signal SIGSEGV, Segmentation fault.
__strchr_avx2 () at ../sysdeps/x86_64/multiarch/strchr-avx2.S:65
65	../sysdeps/x86_64/multiarch/strchr-avx2.S: No such file or directory.
(gdb) bt
#0  __strchr_avx2 () at ../sysdeps/x86_64/multiarch/strchr-avx2.S:65
#1  0x00007ffff7c94e5d in uv_ip6_addr (ip=0x0, port=9999, addr=0x5555555f16a0)
    at /home/tomc/Projects/ZT/vcpkg/buildtrees/libuv/src/1ba00a27b8-94fcdf9fd7.clean/src/uv-common.c:244
#2  0x00007ffff7c4431e in Ziti_resolve (host=0x0, port=0x7fffffffe239 "9999", hints=0x7fffffffcb70, addrlist=0x7fffffffcb10)
    at /home/tomc/Projects/ZT/zitify/build/_deps/ziti-src/library/zitilib.c:1257
#3  0x00007ffff7c3d1be in getaddrinfo(const char * __restrict__, const char * __restrict__, const addrinfo * __restrict__, addrinfo ** __restrict__) (name=0x0, service=0x7fffffffe239 "9999", hints=0x7fffffffcb70, pai=0x7fffffffcb10) at /home/tomc/Projects/ZT/zitify/src/zitify.cpp:113
#4  0x0000555555557c13 in ?? ()
#5  0x00007ffff7829d90 in __libc_start_call_main (main=main@entry=0x5555555567e0, argc=argc@entry=3, argv=argv@entry=0x7fffffffdea8)
    at ../sysdeps/nptl/libc_start_call_main.h:58
#6  0x00007ffff7829e40 in __libc_start_main_impl (main=0x5555555567e0, argc=3, argv=0x7fffffffdea8, init=<optimized out>, fini=<optimized out>, 
    rtld_fini=<optimized out>, stack_end=0x7fffffffde98) at ../csu/libc-start.c:392
#7  0x0000555555558af5 in ?? ()
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