[sr-dev] git:master:e46c90c5: core: add an option to trigger also an RST on tcp connection close

Module: kamailio Branch: master Commit: e46c90c5ca98a9fba08382686c25c707efd57bf3 URL: https://github.com/kamailio/kamailio/commit/e46c90c5ca98a9fba08382686c25c70… Author: Rick Barenthin &lt;rick(a)ng-voice.com&gt; Committer: Daniel-Constantin Mierla &lt;miconda(a)gmail.com&gt; Date: 2022-05-16T08:01:02+02:00 core: add an option to trigger also an RST on tcp connection close - This gives an option to also send RST in case kamailio closes the connection. There are cases where a FIN,ACK back forth leaves the connection in the host in TIME_WAIT state, but the ports on both sides are fixed. This leads to no request can send until the TIME_WAIT state is gone. --- Modified: src/core/cfg.lex Modified: src/core/cfg.y Modified: src/core/tcp_main.c Modified: src/core/tcp_options.c Modified: src/core/tcp_options.h --- Diff: https://github.com/kamailio/kamailio/commit/e46c90c5ca98a9fba08382686c25c70… Patch: https://github.com/kamailio/kamailio/commit/e46c90c5ca98a9fba08382686c25c70… --- diff --git a/src/core/cfg.lex b/src/core/cfg.lex index e5e269ebc0..fc259b2147 100644 --- a/src/core/cfg.lex +++ b/src/core/cfg.lex @@ -421,6 +421,7 @@ TCP_OPT_CRLF_PING "tcp_crlf_ping" TCP_OPT_ACCEPT_NO_CL "tcp_accept_no_cl" TCP_OPT_ACCEPT_HEP3 "tcp_accept_hep3" TCP_OPT_ACCEPT_HAPROXY "tcp_accept_haproxy" +TCP_OPT_CLOSE_RST "tcp_close_rst" TCP_CLONE_RCVBUF "tcp_clone_rcvbuf" TCP_REUSE_PORT "tcp_reuse_port" TCP_WAIT_DATA "tcp_wait_data" @@ -917,6 +918,7 @@ IMPORTFILE "import_file" return TCP_OPT_ACCEPT_HEP3; } <INITIAL>{TCP_OPT_ACCEPT_HAPROXY} { count(); yylval.strval=yytext; return TCP_OPT_ACCEPT_HAPROXY; } +<INITIAL>{TCP_OPT_CLOSE_RST} { count(); yylval.strval=yytext; return TCP_OPT_CLOSE_RST; } <INITIAL>{TCP_CLONE_RCVBUF} { count(); yylval.strval=yytext; return TCP_CLONE_RCVBUF; } <INITIAL>{TCP_REUSE_PORT} { count(); yylval.strval=yytext; return TCP_REUSE_PORT; } diff --git a/src/core/cfg.y b/src/core/cfg.y index 7db37bbc09..5b5c51258d 100644 --- a/src/core/cfg.y +++ b/src/core/cfg.y @@ -450,6 +450,7 @@ extern char *default_routename; %token TCP_OPT_ACCEPT_NO_CL %token TCP_OPT_ACCEPT_HEP3 %token TCP_OPT_ACCEPT_HAPROXY +%token TCP_OPT_CLOSE_RST %token TCP_CLONE_RCVBUF %token TCP_REUSE_PORT %token TCP_WAIT_DATA @@ -1301,6 +1302,14 @@ assign_stm: #endif } | TCP_OPT_ACCEPT_HAPROXY EQUAL error { yyerror("boolean value expected"); } + | TCP_OPT_CLOSE_RST EQUAL NUMBER { + #ifdef USE_TCP + tcp_default_cfg.close_rst=$3; + #else + warn("tcp support not compiled in"); + #endif + } + | TCP_OPT_CLOSE_RST EQUAL error { yyerror("boolean value expected"); } | TCP_CLONE_RCVBUF EQUAL NUMBER { #ifdef USE_TCP diff --git a/src/core/tcp_main.c b/src/core/tcp_main.c index c60ce7f2b2..b046d9a848 100644 --- a/src/core/tcp_main.c +++ b/src/core/tcp_main.c @@ -3209,6 +3209,13 @@ inline static void tcpconn_close_main_fd(struct tcp_connection* tcpconn) #ifdef TCP_FD_CACHE if (likely(cfg_get(tcp, tcp_cfg, fd_cache))) shutdown(fd, SHUT_RDWR); #endif /* TCP_FD_CACHE */ + if(unlikely(cfg_get(tcp, tcp_cfg, close_rst))) { + struct linger sl = { + .l_onoff = 1, /* non-zero value enables linger option in kernel */ + .l_linger = 0, /* timeout interval in seconds */ + }; + setsockopt(fd, SOL_SOCKET, SO_LINGER, &sl, sizeof(sl)); + } if (unlikely(tcp_safe_close(fd)<0)) LM_ERR("(%p): %s close(%d) failed (flags 0x%x): %s (%d)\n", tcpconn, su2a(&tcpconn->rcv.src_su, sizeof(tcpconn->rcv.src_su)), diff --git a/src/core/tcp_options.c b/src/core/tcp_options.c index 54f23a0cdb..211bcfb1e9 100644 --- a/src/core/tcp_options.c +++ b/src/core/tcp_options.c @@ -110,6 +110,8 @@ static cfg_def_t tcp_cfg_def[] = { "reuse TCP ports "}, { "wait_data_ms", CFG_VAR_INT | CFG_ATOMIC, 0, 7200000, 0, 0, "wait for data on new tcp connetions (milliseconds)"}, + { "close_rst", CFG_VAR_INT | CFG_READONLY, 0, 1, 0, 0, + "trigger an RST on connection close"}, /* internal and/or "fixed" versions of some vars (not supposed to be writeable, read will provide only debugging value*/ { "rd_buf_size", CFG_VAR_INT | CFG_ATOMIC, 512, 16777216, 0, 0, @@ -167,6 +169,7 @@ void init_tcp_options() tcp_default_cfg.wq_blk_size=DEFAULT_TCP_WBUF_SIZE; tcp_default_cfg.reuse_port=0; tcp_default_cfg.wait_data_ms=5000; + tcp_default_cfg.close_rst=0; } diff --git a/src/core/tcp_options.h b/src/core/tcp_options.h index 284956647b..dd4d8ac20c 100644 --- a/src/core/tcp_options.h +++ b/src/core/tcp_options.h @@ -139,6 +139,7 @@ struct cfg_group_tcp{ int accept_no_cl; /* on/off - accept messages without content-length */ int reuse_port; /* enable SO_REUSEPORT */ int wait_data_ms; /* wait for data in milliseconds */ + int close_rst; /* on /off trigger an RST on connection close */ /* internal, "fixed" vars */ unsigned int rd_buf_size; /* read buffer size (should be > max. datagram)*/