0.6 #5

donald · 2021-05-25T07:50:04Z

less and better error log
cosmetics

Quote gcc manual: "These functions are intended to replace the legacy ‘__sync’ builtins. The main difference is that the memory order that is requested is a parameter to the functions. New code should always use the ‘__atomic’ builtins rather than the ‘__sync’ builtins. Same assembler code generated on x86_64 for both builtins and no matter what memory order is specified: lock xaddl %eax, debug_remaining_connects(%rip) On ppc, however, __sync_fetch_and_sub creates code for sequential consistency and puts a "sync" instruction before the decrement (which is done atomicially between "lwarx" and "stwcx" instructions) and a "isync" instruction behind it. These two instructions are omitted when only relaxed consistency is requested: sync # optional L22: lwarx 9,0,27 addi 10,9,-1 stwcx. 10,0,27 bne 0,.L22 isync # optional Not, that it would matter at all :-) Make this change anyway to get used to the recommended builtins.

When SSL sees a client hangup, SSL_get_error currently returns SSL_ERROR_SYSCALL. The page at [1] says in section BUGS, that errno would be 0 in this case: The SSL_ERROR_SYSCALL with errno value of 0 indicates unexpected EOF from the peer. To my experimentation, this is not true. errno is left unchanged instead. The page at [2] says, that ERR_get_error could be used to distinguish between EOF and some errno indicated failure: SSL_ERROR_SYSCALL Some I/O error occurred. The OpenSSL error queue may contain more information on the error. If the error queue is empty (i.e. ERR_get_error() returns 0), ret can be used to find out more about the error: If ret == 0, an EOF was observed that violates the protocol. If ret == -1, the underlying BIO reported an I/O error (for socket I/O on Unix systems, consult errno for details). But to my experimentation, this is not true either. In both cases, ERR_get_error doesn't have any further information and ret (from SSL_accept) is -1 in both cases. This might be fixed in OpenSLL 3.0 [3]: On an unexpected EOF, versions before OpenSSL 3.0 returned SSL_ERROR_SYSCALL, nothing was added to the error stack, and errno was 0. Since OpenSSL 3.0 the returned error is SSL_ERROR_SSL with a meaningful error on the error stack. Although it is ugly, we only have the option to set errno to zero before the operation. do this in ssl_read_with_timeout and ssl_accept_with_timeout. [1]: https://www.openssl.org/docs/man1.1.1/man3/SSL_get_error.html [2]: https://linux.die.net/man/3/ssl_get_error [3]: https://www.openssl.org/docs/manmaster/man3/SSL_get_error.html

Use COMMON_LOG to log failures from wait_rd_with_timeout which includes a timeout.

The call `psslerror("")` prints a line with ":" only. Make the string optional so that NULL or "" won't output anything.

donald added 7 commits May 20, 2021 16:57

mxshadowsrv: Do not log shadow reload to stderr

34a9bf2

common.h: Log all failues of ssl_*_with_timeout

36d93d4

Use COMMON_LOG to log failures from wait_rd_with_timeout which includes a timeout.

common.h: Make error string optional

19e11ec

The call `psslerror("")` prints a line with ":" only. Make the string optional so that NULL or "" won't output anything.

mxshadowsrv: Avoid redundant error messages

8693da8

Makefile: Remove unneeded dependencies

41fb135

donald merged commit 4241710 into main May 25, 2021

0.6 #5

0.6 #5

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donald commented May 25, 2021