From d293c3ff700c1a0992a32dc3da9ae18964893c23 Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Tue, 9 Apr 2019 16:30:50 +0200 Subject: Revert "epmd: Support 32-bit creation values in local node" This reverts commit bd8f6106d44a58c261920eef72842bb3bc5a4968. PLUS a little change in epmd_srv.c:750 ("4" -> "replylen") that was part of e2cf4a8a4b03b9f430ba228276c3b2629159e832 by mistake. --- erts/epmd/epmd.mk | 2 +- erts/epmd/src/epmd.h | 1 - erts/epmd/src/epmd_int.h | 10 ++---- erts/epmd/src/epmd_srv.c | 89 +++++++++++++++++++++--------------------------- 4 files changed, 42 insertions(+), 60 deletions(-) (limited to 'erts/epmd') diff --git a/erts/epmd/epmd.mk b/erts/epmd/epmd.mk index f6889a7ff1..b1fd04dc04 100644 --- a/erts/epmd/epmd.mk +++ b/erts/epmd/epmd.mk @@ -67,5 +67,5 @@ EPMD_NODE_TYPE=110 # Distribution format 5 contains the new md5 based handshake. EPMD_DIST_LOW=5 -EPMD_DIST_HIGH=6 +EPMD_DIST_HIGH=5 diff --git a/erts/epmd/src/epmd.h b/erts/epmd/src/epmd.h index 7332294d3d..cffcd4ae7a 100644 --- a/erts/epmd/src/epmd.h +++ b/erts/epmd/src/epmd.h @@ -26,7 +26,6 @@ #define EPMD_ALIVE2_REQ 'x' #define EPMD_PORT2_REQ 'z' #define EPMD_ALIVE2_RESP 'y' -#define EPMD_ALIVE2_X_RESP 'v' #define EPMD_PORT2_RESP 'w' #define EPMD_NAMES_REQ 'n' diff --git a/erts/epmd/src/epmd_int.h b/erts/epmd/src/epmd_int.h index a5156a142e..ed9bbdb8cd 100644 --- a/erts/epmd/src/epmd_int.h +++ b/erts/epmd/src/epmd_int.h @@ -277,12 +277,6 @@ static const struct in6_addr in6addr_loopback = #define put_int16(i, s) {((unsigned char*)(s))[0] = ((i) >> 8) & 0xff; \ ((unsigned char*)(s))[1] = (i) & 0xff;} -#define put_int32(i, s) do {((char*)(s))[0] = (char)((i) >> 24) & 0xff; \ - ((char*)(s))[1] = (char)((i) >> 16) & 0xff; \ - ((char*)(s))[2] = (char)((i) >> 8) & 0xff; \ - ((char*)(s))[3] = (char)(i) & 0xff;} \ - while (0) - #if defined(__GNUC__) # define EPMD_INLINE __inline__ #elif defined(__WIN32__) @@ -313,10 +307,10 @@ struct enode { int fd; /* The socket in use */ unsigned short port; /* Port number of Erlang node */ char symname[MAXSYMLEN+1]; /* Name of the Erlang node */ - unsigned int cr_counter; /* Used to generate 'creation' numbers */ + short creation; /* Started as a random number 1..3 */ char nodetype; /* 77 = normal erlang node 72 = hidden (c-node */ char protocol; /* 0 = tcp/ipv4 */ - unsigned short highvsn; /* 5: creation=1..3, 6: creation=1..(2^32-1)*/ + unsigned short highvsn; /* 0 = OTP-R3 erts-4.6.x, 1 = OTP-R4 erts-4.7.x*/ unsigned short lowvsn; int extralen; char extra[MAXSYMLEN+1]; diff --git a/erts/epmd/src/epmd_srv.c b/erts/epmd/src/epmd_srv.c index 633ec71e5f..3c6f1fbdf4 100644 --- a/erts/epmd/src/epmd_srv.c +++ b/erts/epmd/src/epmd_srv.c @@ -665,21 +665,6 @@ static int do_accept(EpmdVars *g,int listensock) return conn_open(g,msgsock); } -static void bump_creation(Node* node) -{ - if (++node->cr_counter == 0) - node->cr_counter = 1; -} -static unsigned int get_creation(Node* node) -{ - if (node->highvsn >= 6) { - return node->cr_counter; /* 1..(2^32-1)*/ - } - else { - return (node->cr_counter - 1) % 3 + 1; /* 1..3 */ - } -} - /* buf is actually one byte larger than bsize, giving place for null termination */ static void do_request(g, fd, s, buf, bsize) @@ -721,10 +706,8 @@ static void do_request(g, fd, s, buf, bsize) unsigned char protocol; unsigned short highvsn; unsigned short lowvsn; - unsigned int creation; int namelen; int extralen; - int replylen; char *name; char *extra; eport = get_int16(&buf[1]); @@ -754,22 +737,17 @@ static void do_request(g, fd, s, buf, bsize) extra = &buf[11+namelen+2]; extra[extralen]='\000'; - node = node_reg2(g, namelen, name, fd, eport, nodetype, protocol, - highvsn, lowvsn, extralen, extra); - creation = node ? get_creation(node) : 99; - wbuf[1] = node ? 0 : 1; /* ok | error */ - if (highvsn >= 6) { - wbuf[0] = EPMD_ALIVE2_X_RESP; - put_int32(creation, wbuf+2); - replylen = 6; - } - else { - wbuf[0] = EPMD_ALIVE2_RESP; - put_int16(creation, wbuf+2); - replylen = 4; - } + wbuf[0] = EPMD_ALIVE2_RESP; + if ((node = node_reg2(g, namelen, name, fd, eport, nodetype, protocol, + highvsn, lowvsn, extralen, extra)) == NULL) { + wbuf[1] = 1; /* error */ + put_int16(99, wbuf+2); + } else { + wbuf[1] = 0; /* ok */ + put_int16(node->creation, wbuf+2); + } - if (!reply(g, fd, wbuf, replylen)) + if (!reply(g, fd, wbuf, 4)) { node_unreg(g, name); dbg_tty_printf(g,1,"** failed to send ALIVE2_RESP for \"%s\"", @@ -1222,8 +1200,8 @@ static int node_unreg(EpmdVars *g,char *name) for (; node; prev = &node->next, node = node->next) if (is_same_str(node->symname, name)) { - dbg_tty_printf(g,1,"unregistering '%s:%u', port %d", - node->symname, get_creation(node), node->port); + dbg_tty_printf(g,1,"unregistering '%s:%d', port %d", + node->symname, node->creation, node->port); *prev = node->next; /* Link out from "reg" list */ @@ -1257,8 +1235,8 @@ static int node_unreg_sock(EpmdVars *g,int fd) for (; node; prev = &node->next, node = node->next) if (node->fd == fd) { - dbg_tty_printf(g,1,"unregistering '%s:%u', port %d", - node->symname, get_creation(node), node->port); + dbg_tty_printf(g,1,"unregistering '%s:%d', port %d", + node->symname, node->creation, node->port); *prev = node->next; /* Link out from "reg" list */ @@ -1286,8 +1264,19 @@ static int node_unreg_sock(EpmdVars *g,int fd) } /* - * Register a new node + * Finding a node slot and a (name,creation) name is a bit tricky. + * We try in order + * + * 1. If the name was used before and we can reuse that slot but use + * a new "creation" digit in the range 1..3. + * + * 2. We try to find a new unused slot. + * + * 3. We try to use an used slot this isn't used any longer. + * FIXME: The criteria for *what* slot to steal should be improved. + * Perhaps use the oldest or something. */ + static Node *node_reg2(EpmdVars *g, int namelen, char* name, @@ -1357,7 +1346,7 @@ static Node *node_reg2(EpmdVars *g, } /* Try to find the name in the used queue so that we - can change "creation" number */ + can change "creation" number 1..3 */ prev = NULL; @@ -1386,8 +1375,9 @@ static Node *node_reg2(EpmdVars *g, g->nodes.unreg_count--; - /* When reusing we change the "creation" number */ - bump_creation(node); + /* When reusing we change the "creation" number 1..3 */ + + node->creation = node->creation % 3 + 1; break; } @@ -1414,8 +1404,7 @@ static Node *node_reg2(EpmdVars *g, exit(1); } - node->cr_counter = current_time(g); /* "random" */ - bump_creation(node); + node->creation = (current_time(g) % 3) + 1; /* "random" 1-3 */ } } @@ -1434,11 +1423,11 @@ static Node *node_reg2(EpmdVars *g, select_fd_set(g, fd); if (highvsn == 0) { - dbg_tty_printf(g,1,"registering '%s:%u', port %d", - node->symname, get_creation(node), node->port); + dbg_tty_printf(g,1,"registering '%s:%d', port %d", + node->symname, node->creation, node->port); } else { - dbg_tty_printf(g,1,"registering '%s:%u', port %d", - node->symname, get_creation(node), node->port); + dbg_tty_printf(g,1,"registering '%s:%d', port %d", + node->symname, node->creation, node->port); dbg_tty_printf(g,1,"type %d proto %d highvsn %d lowvsn %d", nodetype, protocol, highvsn, lowvsn); } @@ -1572,8 +1561,8 @@ static void print_names(EpmdVars *g) for (node = g->nodes.reg; node; node = node->next) { - fprintf(stderr,"***** active name \"%s#%u\" at port %d, fd = %d\r\n", - node->symname, get_creation(node), node->port, node->fd); + fprintf(stderr,"***** active name \"%s#%d\" at port %d, fd = %d\r\n", + node->symname, node->creation, node->port, node->fd); count ++; } @@ -1583,8 +1572,8 @@ static void print_names(EpmdVars *g) for (node = g->nodes.unreg; node; node = node->next) { - fprintf(stderr,"***** old/unused name \"%s#%u\"\r\n", - node->symname, get_creation(node)); + fprintf(stderr,"***** old/unused name \"%s#%d\"\r\n", + node->symname, node->creation); count ++; } -- cgit v1.2.3