diff --git a/src/config.c b/src/config.c index b575561..9cca05f 100644 --- a/src/config.c +++ b/src/config.c @@ -1,977 +1,970 @@ /* * Copyright (C) 2011 Jiaju Zhang * Copyright (C) 2013-2014 Philipp Marek * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include #include #include #include #include #include "b_config.h" #include "booth.h" #include "config.h" #include "raft.h" #include "ticket.h" #include "log.h" static int ticket_size = 0; static int ticket_realloc(void) { const int added = 5; int had, want; void *p; had = booth_conf->ticket_allocated; want = had + added; p = realloc(booth_conf->ticket, sizeof(struct ticket_config) * want); if (!p) { log_error("can't alloc more tickets"); return -ENOMEM; } booth_conf->ticket = p; memset(booth_conf->ticket + had, 0, sizeof(struct ticket_config) * added); booth_conf->ticket_allocated = want; return 0; } int add_site(char *address, int type); int add_site(char *addr_string, int type) { int rv; struct booth_site *site; uLong nid; uint32_t mask; int i; rv = 1; if (booth_conf->site_count == MAX_NODES) { log_error("too many nodes"); goto out; } if (strlen(addr_string)+1 >= sizeof(booth_conf->site[0].addr_string)) { log_error("site address \"%s\" too long", addr_string); goto out; } site = booth_conf->site + booth_conf->site_count; site->family = AF_INET; site->type = type; /* Make site_id start at a non-zero point. * Perhaps use hash over string or address? */ strcpy(site->addr_string, addr_string); site->index = booth_conf->site_count; site->bitmask = 1 << booth_conf->site_count; /* Catch site overflow */ assert(site->bitmask); booth_conf->all_bits |= site->bitmask; if (type == SITE) booth_conf->sites_bits |= site->bitmask; site->tcp_fd = -1; booth_conf->site_count++; rv = 0; memset(&site->sa6, 0, sizeof(site->sa6)); nid = crc32(0L, NULL, 0); /* Using the ASCII representation in site->addr_string (both sizeof() * and strlen()) gives quite a lot of collisions; a brute-force run * from 0.0.0.0 to 24.0.0.0 gives ~4% collisions, and this tends to * increase even more. * Whether there'll be a collision in real-life, with 3 or 5 nodes, is * another question ... but for now get the ID from the binary * representation - that had *no* collisions up to 32.0.0.0. */ if (inet_pton(AF_INET, site->addr_string, &site->sa4.sin_addr) > 0) { site->family = AF_INET; site->sa4.sin_family = site->family; site->sa4.sin_port = htons(booth_conf->port); site->saddrlen = sizeof(site->sa4); site->addrlen = sizeof(site->sa4.sin_addr); site->site_id = crc32(nid, (void*)&site->sa4.sin_addr, site->addrlen); } else if (inet_pton(AF_INET6, site->addr_string, &site->sa6.sin6_addr) > 0) { site->family = AF_INET6; site->sa6.sin6_family = site->family; site->sa6.sin6_flowinfo = 0; site->sa6.sin6_port = htons(booth_conf->port); site->saddrlen = sizeof(site->sa6); site->addrlen = sizeof(site->sa6.sin6_addr); site->site_id = crc32(nid, (void*)&site->sa6.sin6_addr, site->addrlen); } else { log_error("Address string \"%s\" is bad", site->addr_string); rv = EINVAL; } /* Make sure we will never collide with NO_ONE, * or be negative (to get "get_local_id() < 0" working). */ mask = 1 << (sizeof(site->site_id)*8 -1); assert(NO_ONE & mask); site->site_id &= ~mask; /* Test for collisions with other sites */ for(i=0; iindex; i++) if (booth_conf->site[i].site_id == site->site_id) { log_error("Got a site-ID collision. Please file a bug on https://github.com/ClusterLabs/booth/issues/new, attaching the configuration file."); exit(1); } out: return rv; } inline static char *skip_while_in(const char *cp, int (*fn)(int), const char *allowed) { /* strchr() returns a pointer to the terminator if *cp == 0. */ while (*cp && (fn(*cp) || strchr(allowed, *cp))) cp++; /* discard "const" qualifier */ return (char*)cp; } inline static char *skip_while(char *cp, int (*fn)(int)) { while (fn(*cp)) cp++; return cp; } inline static char *skip_until(char *cp, char expected) { while (*cp && *cp != expected) cp++; return cp; } static inline int is_end_of_line(char *cp) { char c = *cp; return c == '\n' || c == 0 || c == '#'; } static int add_ticket(const char *name, struct ticket_config **tkp, const struct ticket_config *def) { int rv; struct ticket_config *tk; if (booth_conf->ticket_count == booth_conf->ticket_allocated) { rv = ticket_realloc(); if (rv < 0) return rv; } tk = booth_conf->ticket + booth_conf->ticket_count; booth_conf->ticket_count++; - tk->last_valid_tk = malloc(sizeof(struct ticket_config)); - if (!tk->last_valid_tk) { - log_error("out of memory"); - return -ENOMEM; - } - memset(tk->last_valid_tk, 0, sizeof(struct ticket_config)); - if (!check_max_len_valid(name, sizeof(tk->name))) { log_error("ticket name \"%s\" too long.", name); return -EINVAL; } if (find_ticket_by_name(name, NULL)) { log_error("ticket name \"%s\" used again.", name); return -EINVAL; } if (* skip_while_in(name, isalnum, "-/")) { log_error("ticket name \"%s\" invalid; only alphanumeric names.", name); return -EINVAL; } strcpy(tk->name, name); tk->timeout = def->timeout; tk->term_duration = def->term_duration; tk->retries = def->retries; memcpy(tk->weight, def->weight, sizeof(tk->weight)); if (tkp) *tkp = tk; return 0; } static int postproc_ticket(struct ticket_config *tk) { if (!tk) return 1; if (!tk->renewal_freq) { tk->renewal_freq = tk->term_duration/2; } if (tk->timeout*(tk->retries+1) >= tk->renewal_freq) { log_error("%s: total amount of time to " "retry sending packets cannot exceed " "renewal frequency " "(%d*(%d+1) >= %d)", tk->name, tk->timeout, tk->retries, tk->renewal_freq); return 0; } return 1; } /* returns number of weights, or -1 on bad input. */ static int parse_weights(const char *input, int weights[MAX_NODES]) { int i, v; char *cp; for(i=0; i= MAX_ARGS) { log_error("too many arguments for the acquire-handler"); free(tk_test.prog); return -1; } tk_test.argv[i++] = p; } while (p); return 0; } struct toktab grant_type[] = { { "auto", GRANT_AUTO}, { "manual", GRANT_MANUAL}, { NULL, 0}, }; struct toktab attr_op[] = { {"eq", ATTR_OP_EQ}, {"ne", ATTR_OP_NE}, {NULL, 0}, }; static int lookup_tokval(char *key, struct toktab *tab) { struct toktab *tp; for (tp = tab; tp->str; tp++) { if (!strcmp(tp->str, key)) return tp->val; } return 0; } /* attribute prerequisite */ static int parse_attr_prereq(char *val, struct ticket_config *tk) { struct attr_prereq *ap = NULL; char *p; ap = (struct attr_prereq *)calloc(1, sizeof(struct attr_prereq)); if (!ap) { log_error("out of memory"); return -1; } p = strtok(val, " \t"); if (!p) { log_error("not enough arguments to attr-prereq"); goto err_out; } ap->grant_type = lookup_tokval(p, grant_type); if (!ap->grant_type) { log_error("%s is not a grant type", p); goto err_out; } p = strtok(NULL, " \t"); if (!p) { log_error("not enough arguments to attr-prereq"); goto err_out; } if (!(ap->attr_name = strdup(p))) { log_error("out of memory"); goto err_out; } p = strtok(NULL, " \t"); if (!p) { log_error("not enough arguments to attr-prereq"); goto err_out; } ap->op = lookup_tokval(p, attr_op); if (!ap->op) { log_error("%s is not an attribute operation", p); goto err_out; } p = strtok(NULL, " \t"); if (!p) { log_error("not enough arguments to attr-prereq"); goto err_out; } if (!(ap->attr_val = strdup(p))) { log_error("out of memory"); goto err_out; } tk->attr_prereqs = g_list_append(tk->attr_prereqs, ap); if (!tk->attr_prereqs) { log_error("out of memory"); goto err_out; } return 0; err_out: if (ap) { if (ap->attr_val) free(ap->attr_val); if (ap->attr_name) free(ap->attr_name); free(ap); } return -1; } extern int poll_timeout; int read_config(const char *path, int type) { char line[1024]; FILE *fp; char *s, *key, *val, *end_of_key; const char *error; char *cp, *cp2; int i; int lineno = 0; int got_transport = 0; int min_timeout = 0; struct ticket_config defaults = { { 0 } }; struct ticket_config *current_tk = NULL; fp = fopen(path, "r"); if (!fp) { log_error("failed to open %s: %s", path, strerror(errno)); return -1; } booth_conf = malloc(sizeof(struct booth_config) + TICKET_ALLOC * sizeof(struct ticket_config)); if (!booth_conf) { log_error("failed to alloc memory for booth config"); return -ENOMEM; } memset(booth_conf, 0, sizeof(struct booth_config) + TICKET_ALLOC * sizeof(struct ticket_config)); ticket_size = TICKET_ALLOC; booth_conf->proto = UDP; booth_conf->port = BOOTH_DEFAULT_PORT; booth_conf->maxtimeskew = BOOTH_DEFAULT_MAX_TIME_SKEW; booth_conf->authkey[0] = '\0'; /* Provide safe defaults. -1 is reserved, though. */ booth_conf->uid = -2; booth_conf->gid = -2; strcpy(booth_conf->site_user, "hacluster"); strcpy(booth_conf->site_group, "haclient"); strcpy(booth_conf->arb_user, "nobody"); strcpy(booth_conf->arb_group, "nobody"); parse_weights("", defaults.weight); defaults.clu_test.prog = NULL; defaults.clu_test.pid = 0; defaults.clu_test.status = 0; defaults.clu_test.progstate = EXTPROG_IDLE; defaults.term_duration = DEFAULT_TICKET_EXPIRY; defaults.timeout = DEFAULT_TICKET_TIMEOUT; defaults.retries = DEFAULT_RETRIES; defaults.acquire_after = 0; error = ""; log_debug("reading config file %s", path); while (fgets(line, sizeof(line), fp)) { lineno++; s = skip_while(line, isspace); if (is_end_of_line(s) || *s == '#') continue; key = s; /* Key */ end_of_key = skip_while_in(key, isalnum, "-_"); if (end_of_key == key) { error = "No key"; goto err; } if (!*end_of_key) goto exp_equal; /* whitespace, and something else but nothing more? */ s = skip_while(end_of_key, isspace); if (*s != '=') { exp_equal: error = "Expected '=' after key"; goto err; } s++; /* It's my buffer, and I terminate if I want to. */ /* But not earlier than that, because we had to check for = */ *end_of_key = 0; /* Value tokenizing */ s = skip_while(s, isspace); switch (*s) { case '"': case '\'': val = s+1; s = skip_until(val, *s); /* Terminate value */ if (!*s) { error = "Unterminated quoted string"; goto err; } /* Remove and skip quote */ *s = 0; s++; if (*(s = skip_while(s, isspace)) && *s != '#') { error = "Surplus data after value"; goto err; } *s = 0; break; case 0: no_value: error = "No value"; goto err; break; default: val = s; /* Rest of line. */ i = strlen(s); /* i > 0 because of "case 0" above. */ while (i > 0 && isspace(s[i-1])) i--; s += i; *s = 0; } if (val == s) goto no_value; if (strlen(key) > BOOTH_NAME_LEN || strlen(val) > BOOTH_NAME_LEN) { error = "key/value too long"; goto err; } if (strcmp(key, "transport") == 0) { if (got_transport) { error = "config file has multiple transport lines"; goto err; } if (strcasecmp(val, "UDP") == 0) booth_conf->proto = UDP; else if (strcasecmp(val, "SCTP") == 0) booth_conf->proto = SCTP; else { error = "invalid transport protocol"; goto err; } got_transport = 1; continue; } if (strcmp(key, "port") == 0) { booth_conf->port = atoi(val); continue; } if (strcmp(key, "name") == 0) { safe_copy(booth_conf->name, val, BOOTH_NAME_LEN, "name"); continue; } #if HAVE_LIBGCRYPT || HAVE_LIBMHASH if (strcmp(key, "authfile") == 0) { safe_copy(booth_conf->authfile, val, BOOTH_PATH_LEN, "authfile"); continue; } if (strcmp(key, "maxtimeskew") == 0) { booth_conf->maxtimeskew = atoi(val); continue; } #endif if (strcmp(key, "site") == 0) { if (add_site(val, SITE)) goto out; continue; } if (strcmp(key, "arbitrator") == 0) { if (add_site(val, ARBITRATOR)) goto out; continue; } if (strcmp(key, "site-user") == 0) { safe_copy(booth_conf->site_user, optarg, BOOTH_NAME_LEN, "site-user"); continue; } if (strcmp(key, "site-group") == 0) { safe_copy(booth_conf->site_group, optarg, BOOTH_NAME_LEN, "site-group"); continue; } if (strcmp(key, "arbitrator-user") == 0) { safe_copy(booth_conf->arb_user, optarg, BOOTH_NAME_LEN, "arbitrator-user"); continue; } if (strcmp(key, "arbitrator-group") == 0) { safe_copy(booth_conf->arb_group, optarg, BOOTH_NAME_LEN, "arbitrator-group"); continue; } if (strcmp(key, "debug") == 0) { if (type != CLIENT && type != GEOSTORE) debug_level = max(debug_level, atoi(val)); continue; } if (strcmp(key, "ticket") == 0) { if (current_tk && strcmp(current_tk->name, "__defaults__")) { if (!postproc_ticket(current_tk)) { goto out; } } if (!strcmp(val, "__defaults__")) { current_tk = &defaults; } else if (add_ticket(val, ¤t_tk, &defaults)) { goto out; } continue; } /* current_tk must be allocated at this point, otherwise * we don't know to which ticket the key refers */ if (!current_tk) { error = "Unexpected keyword"; goto err; } if (strcmp(key, "expire") == 0) { current_tk->term_duration = read_time(val); if (current_tk->term_duration <= 0) { error = "Expected time >0 for expire"; goto err; } continue; } if (strcmp(key, "timeout") == 0) { current_tk->timeout = read_time(val); if (current_tk->timeout <= 0) { error = "Expected time >0 for timeout"; goto err; } if (!min_timeout) { min_timeout = current_tk->timeout; } else { min_timeout = min(min_timeout, current_tk->timeout); } continue; } if (strcmp(key, "retries") == 0) { current_tk->retries = strtol(val, &s, 0); if (*s || s == val || current_tk->retries<3 || current_tk->retries > 100) { error = "Expected plain integer value in the range [3, 100] for retries"; goto err; } continue; } if (strcmp(key, "renewal-freq") == 0) { current_tk->renewal_freq = read_time(val); if (current_tk->renewal_freq <= 0) { error = "Expected time >0 for renewal-freq"; goto err; } continue; } if (strcmp(key, "acquire-after") == 0) { current_tk->acquire_after = read_time(val); if (current_tk->acquire_after < 0) { error = "Expected time >=0 for acquire-after"; goto err; } continue; } if (strcmp(key, "before-acquire-handler") == 0) { if (parse_extprog(val, current_tk)) { goto err; } continue; } if (strcmp(key, "attr-prereq") == 0) { if (parse_attr_prereq(val, current_tk)) { goto err; } continue; } if (strcmp(key, "weights") == 0) { if (parse_weights(val, current_tk->weight) < 0) goto out; continue; } error = "Unknown keyword"; goto err; } if ((booth_conf->site_count % 2) == 0) { log_warn("Odd number of nodes is strongly recommended!"); } /* Default: make config name match config filename. */ if (!booth_conf->name[0]) { cp = strrchr(path, '/'); cp = cp ? cp+1 : (char *)path; cp2 = strrchr(cp, '.'); if (!cp2) cp2 = cp + strlen(cp); if (cp2-cp >= BOOTH_NAME_LEN) { log_error("booth config file name too long"); goto err; } strncpy(booth_conf->name, cp, cp2-cp); *(booth_conf->name+(cp2-cp)) = '\0'; } if (!postproc_ticket(current_tk)) { goto out; } poll_timeout = min(POLL_TIMEOUT, min_timeout/10); if (!poll_timeout) poll_timeout = POLL_TIMEOUT; return 0; err: out: log_error("%s in config file line %d", error, lineno); free(booth_conf); booth_conf = NULL; return -1; } int check_config(int type) { struct passwd *pw; struct group *gr; char *cp, *input; if (!booth_conf) return -1; input = (type == ARBITRATOR) ? booth_conf->arb_user : booth_conf->site_user; if (!*input) goto u_inval; if (isdigit(input[0])) { booth_conf->uid = strtol(input, &cp, 0); if (*cp != 0) { u_inval: log_error("User \"%s\" cannot be resolved into a UID.", input); return ENOENT; } } else { pw = getpwnam(input); if (!pw) goto u_inval; booth_conf->uid = pw->pw_uid; } input = (type == ARBITRATOR) ? booth_conf->arb_group : booth_conf->site_group; if (!*input) goto g_inval; if (isdigit(input[0])) { booth_conf->gid = strtol(input, &cp, 0); if (*cp != 0) { g_inval: log_error("Group \"%s\" cannot be resolved into a UID.", input); return ENOENT; } } else { gr = getgrnam(input); if (!gr) goto g_inval; booth_conf->gid = gr->gr_gid; } return 0; } static int get_other_site(struct booth_site **node) { struct booth_site *n; int i; *node = NULL; if (!booth_conf) return 0; for (i = 0; i < booth_conf->site_count; i++) { n = booth_conf->site + i; if (n != local && n->type == SITE) { if (!*node) { *node = n; } else { return 0; } } } return !*node ? 0 : 1; } int find_site_by_name(unsigned char *site, struct booth_site **node, int any_type) { struct booth_site *n; int i; if (!booth_conf) return 0; if (!strcmp(site, OTHER_SITE)) return get_other_site(node); for (i = 0; i < booth_conf->site_count; i++) { n = booth_conf->site + i; if ((n->type == SITE || any_type) && strcmp(n->addr_string, site) == 0) { *node = n; return 1; } } return 0; } int find_site_by_id(uint32_t site_id, struct booth_site **node) { struct booth_site *n; int i; if (site_id == NO_ONE) { *node = no_leader; return 1; } if (!booth_conf) return 0; for (i = 0; i < booth_conf->site_count; i++) { n = booth_conf->site + i; if (n->site_id == site_id) { *node = n; return 1; } } return 0; } const char *type_to_string(int type) { switch (type) { case ARBITRATOR: return "arbitrator"; case SITE: return "site"; case CLIENT: return "client"; case GEOSTORE: return "attr"; } return "??invalid-type??"; } diff --git a/src/inline-fn.h b/src/inline-fn.h index d276c42..77958a5 100644 --- a/src/inline-fn.h +++ b/src/inline-fn.h @@ -1,312 +1,312 @@ /* * Copyright (C) 2013-2014 Philipp Marek * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef _INLINE_FN_H #define _INLINE_FN_H #include #include #include #include #include "timer.h" #include "config.h" #include "transport.h" inline static uint32_t get_local_id(void) { return local ? local->site_id : -1; } inline static uint32_t get_node_id(struct booth_site *node) { return node ? node->site_id : 0; } /** Returns number of seconds left, if any. */ inline static int term_time_left(struct ticket_config *tk) { int left = 0; if (is_time_set(&tk->term_expires)) { left = time_left(&tk->term_expires); } return (left < 0) ? 0 : left; } inline static int leader_and_valid(struct ticket_config *tk) { if (tk->leader != local) return 0; return term_time_left(tk); } /** Is this some leader? */ inline static int is_owned(const struct ticket_config *tk) { return (tk->leader && tk->leader != no_leader); } inline static int is_resend(struct ticket_config *tk) { timetype now; get_time(&now); return time_sub_int(&now, &tk->req_sent_at) >= tk->timeout; } static inline void init_header_bare(struct boothc_header *h) { timetype now; assert(local && local->site_id); h->magic = htonl(BOOTHC_MAGIC); h->version = htonl(BOOTHC_VERSION); h->from = htonl(local->site_id); if (is_auth_req()) { get_time(&now); h->opts = htonl(BOOTH_OPT_AUTH); h->secs = htonl(secs_since_epoch(&now)); h->usecs = htonl(get_usecs(&now)); } else { h->opts = htonl(0); h->secs = htonl(0); h->usecs = htonl(0); } } /* get the _real_ message length out of the header */ #define sendmsglen(msg) ntohl((msg)->header.length) static inline void init_header(struct boothc_header *h, int cmd, int request, int options, int result, int reason, int data_len) { init_header_bare(h); h->length = htonl(data_len - (is_auth_req() ? 0 : sizeof(struct hmac))); h->cmd = htonl(cmd); h->request = htonl(request); h->options = htonl(options); h->result = htonl(result); h->reason = htonl(reason); } #define my_last_term(tk) \ - (((tk)->state == ST_CANDIDATE && (tk)->last_valid_tk->current_term) ? \ + (((tk)->state == ST_CANDIDATE && (tk)->last_valid_tk) ? \ (tk)->last_valid_tk->current_term : (tk)->current_term) extern int TIME_RES, TIME_MULT; #define msg_term_time(msg) \ ntohl((msg)->ticket.term_valid_for)*TIME_RES/TIME_MULT #define set_msg_term_time(msg, tk) \ (msg)->ticket.term_valid_for = htonl(term_time_left(tk)*TIME_MULT/TIME_RES) static inline void init_ticket_msg(struct boothc_ticket_msg *msg, int cmd, int request, int rv, int reason, struct ticket_config *tk) { assert(sizeof(msg->ticket.id) == sizeof(tk->name)); init_header(&msg->header, cmd, request, 0, rv, reason, sizeof(*msg)); if (!tk) { memset(&msg->ticket, 0, sizeof(msg->ticket)); } else { memcpy(msg->ticket.id, tk->name, sizeof(msg->ticket.id)); msg->ticket.leader = htonl(get_node_id( (tk->leader && tk->leader != no_leader) ? tk->leader : (tk->voted_for ? tk->voted_for : no_leader))); msg->ticket.term = htonl(tk->current_term); set_msg_term_time(msg, tk); } } static inline void init_attr_msg(struct boothc_attr_msg *msg, int cmd, int request, int rv, int reason, struct ticket_config *tk, char *attr_name, struct geo_attr *attr) { assert(tk); assert(attr); init_header(&msg->header, cmd, request, 0, rv, reason, sizeof(*msg)); if (!tk) { memset(&msg->attr.tkt_id, 0, sizeof(msg->attr.tkt_id)); } else { memcpy(msg->attr.tkt_id, tk->name, sizeof(msg->attr.tkt_id)); } memcpy(msg->attr.name, attr_name, sizeof(msg->attr.name)); memcpy(msg->attr.val, attr->val, sizeof(msg->attr.val)); } static inline struct booth_transport const *transport(void) { return booth_transport + booth_conf->proto; } static inline const char *site_string(struct booth_site *site) { return site ? site->addr_string : "NONE"; } static inline const char *ticket_leader_string(struct ticket_config *tk) { return site_string(tk->leader); } /* We allow half of the uint32_t to be used; * half of that below, half of that above the current known "good" value. * 0 UINT32_MAX * |--------------------------+----------------+------------| * | | | * |--------+-------| allowed range * | * current commit index * * So, on overflow it looks like that: * UINT32_MAX 0 * |--------------------------+-----------||---+------------| * | | | * |--------+-------| allowed range * | * current commit index * * This should be possible by using the same datatype and relying * on the under/overflow semantics. * * * Having 30 bits available, and assuming an expire time of * one minute and a (high) commit index step of 64 == 2^6 (because * of weights), we get 2^24 minutes of range - which is ~750 * years. "Should be enough for everybody." */ static inline int index_is_higher_than(uint32_t c_high, uint32_t c_low) { uint32_t diff; if (c_high == c_low) return 0; diff = c_high - c_low; if (diff < UINT32_MAX/4) return 1; diff = c_low - c_high; if (diff < UINT32_MAX/4) return 0; assert(!"commit index out of range - invalid"); } static inline uint32_t index_max2(uint32_t a, uint32_t b) { return index_is_higher_than(a, b) ? a : b; } static inline uint32_t index_max3(uint32_t a, uint32_t b, uint32_t c) { return index_max2( index_max2(a, b), c); } /* only invoked when ticket leader */ static inline void get_next_election_time(struct ticket_config *tk, timetype *next) { assert(tk->leader == local); /* if last_renewal is not set, which is unusual, it may mean * that the ticket never got updated, i.e. nobody acked * ticket updates (say, due to a temporary connection * problem) * we may try a bit later again */ if (!is_time_set(&tk->last_renewal)) { time_reset(next); } else { interval_add(&tk->last_renewal, tk->renewal_freq, next); } /* if delay_commit is earlier than next, then set next to * delay_commit */ if (is_time_set(&tk->delay_commit) && time_cmp(next, &tk->delay_commit, >)) { copy_time(&tk->delay_commit, next); } } static inline void expect_replies(struct ticket_config *tk, int reply_type) { tk->retry_number = 0; tk->acks_expected = reply_type; tk->acks_received = local->bitmask; get_time(&tk->req_sent_at); } static inline void no_resends(struct ticket_config *tk) { tk->retry_number = 0; tk->acks_expected = 0; } static inline struct booth_site *my_vote(struct ticket_config *tk) { return tk->votes_for[ local->index ]; } static inline int count_bits(uint64_t val) { return __builtin_popcount(val); } static inline int majority_of_bits(struct ticket_config *tk, uint64_t val) { /* Use ">" to get majority decision, even for an even number * of participants. */ return count_bits(val) * 2 > booth_conf->site_count; } static inline int all_replied(struct ticket_config *tk) { return !(tk->acks_received ^ booth_conf->all_bits); } static inline int all_sites_replied(struct ticket_config *tk) { return !((tk->acks_received & booth_conf->sites_bits) ^ booth_conf->sites_bits); } #endif diff --git a/src/raft.c b/src/raft.c index c2978a6..d7daffa 100644 --- a/src/raft.c +++ b/src/raft.c @@ -1,1004 +1,1003 @@ /* * Copyright (C) 2014 Philipp Marek * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include "booth.h" #include "timer.h" #include "transport.h" #include "inline-fn.h" #include "config.h" #include "raft.h" #include "ticket.h" #include "request.h" #include "log.h" inline static void clear_election(struct ticket_config *tk) { int i; struct booth_site *site; tk_log_debug("clear election"); tk->votes_received = 0; foreach_node(i, site) tk->votes_for[site->index] = NULL; } inline static void record_vote(struct ticket_config *tk, struct booth_site *who, struct booth_site *vote) { tk_log_debug("site %s votes for %s", site_string(who), site_string(vote)); if (!tk->votes_for[who->index]) { tk->votes_for[who->index] = vote; tk->votes_received |= who->bitmask; } else { if (tk->votes_for[who->index] != vote) tk_log_warn("%s voted previously " "for %s and now wants to vote for %s (ignored)", site_string(who), site_string(tk->votes_for[who->index]), site_string(vote)); } } static void update_term_from_msg(struct ticket_config *tk, struct boothc_ticket_msg *msg) { uint32_t i; i = ntohl(msg->ticket.term); /* if we failed to start the election, then accept the term * from the leader * */ if (tk->state == ST_CANDIDATE) { tk->current_term = i; } else { tk->current_term = max(i, tk->current_term); } } static void set_ticket_expiry(struct ticket_config *tk, int duration) { set_future_time(&tk->term_expires, duration); } static void update_ticket_from_msg(struct ticket_config *tk, struct booth_site *sender, struct boothc_ticket_msg *msg) { int duration; tk_log_info("updating from %s (%d/%d)", site_string(sender), ntohl(msg->ticket.term), msg_term_time(msg)); duration = min(tk->term_duration, msg_term_time(msg)); set_ticket_expiry(tk, duration); update_term_from_msg(tk, msg); } static void copy_ticket_from_msg(struct ticket_config *tk, struct boothc_ticket_msg *msg) { set_ticket_expiry(tk, msg_term_time(msg)); tk->current_term = ntohl(msg->ticket.term); } static void become_follower(struct ticket_config *tk, struct boothc_ticket_msg *msg) { copy_ticket_from_msg(tk, msg); set_state(tk, ST_FOLLOWER); time_reset(&tk->delay_commit); tk->in_election = 0; /* if we're following and the ticket was granted here * then commit to CIB right away (we're probably restarting) */ if (tk->is_granted) { disown_ticket(tk); ticket_write(tk); } } static void won_elections(struct ticket_config *tk) { set_leader(tk, local); set_state(tk, ST_LEADER); set_ticket_expiry(tk, tk->term_duration); time_reset(&tk->election_end); tk->voted_for = NULL; if (is_time_set(&tk->delay_commit) && all_sites_replied(tk)) { time_reset(&tk->delay_commit); tk_log_debug("reset delay commit as all sites replied"); } save_committed_tkt(tk); ticket_broadcast(tk, OP_HEARTBEAT, OP_ACK, RLT_SUCCESS, 0); tk->ticket_updated = 0; } /* if more than one member got the same (and maximum within that * election) number of votes, then that is a tie */ static int is_tie(struct ticket_config *tk) { int i; struct booth_site *v; int count[MAX_NODES] = { 0, }; int max_votes = 0, max_cnt = 0; for(i=0; isite_count; i++) { v = tk->votes_for[i]; if (!v) continue; count[v->index]++; max_votes = max(max_votes, count[v->index]); } for(i=0; isite_count; i++) { if (count[i] == max_votes) max_cnt++; } return max_cnt > 1; } static struct booth_site *majority_votes(struct ticket_config *tk) { int i, n; struct booth_site *v; int count[MAX_NODES] = { 0, }; for(i=0; isite_count; i++) { v = tk->votes_for[i]; if (!v || v == no_leader) continue; n = v->index; count[n]++; tk_log_debug("Majority: %d %s wants %d %s => %d", i, site_string(&booth_conf->site[i]), n, site_string(v), count[n]); if (count[n]*2 <= booth_conf->site_count) continue; tk_log_debug("Majority reached: %d of %d for %s", count[n], booth_conf->site_count, site_string(v)); return v; } return NULL; } void elections_end(struct ticket_config *tk) { struct booth_site *new_leader; if (is_past(&tk->election_end)) { /* This is previous election timed out */ tk_log_info("elections finished"); } tk->in_election = 0; new_leader = majority_votes(tk); if (new_leader == local) { won_elections(tk); tk_log_info("granted successfully here"); } else if (new_leader) { tk_log_info("ticket granted at %s", site_string(new_leader)); } else { tk_log_info("nobody won elections, new elections"); tk->outcome = RLT_MORE; foreach_tkt_req(tk, notify_client); if (!new_election(tk, NULL, is_tie(tk) ? 2 : 0, OR_AGAIN)) { ticket_activate_timeout(tk); } } } static int newer_term(struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg, int in_election) { uint32_t term; /* it may happen that we hear about our newer term */ if (leader == local) return 0; term = ntohl(msg->ticket.term); /* §5.1 */ if (term > tk->current_term) { set_state(tk, ST_FOLLOWER); if (!in_election) { set_leader(tk, leader); tk_log_info("from %s: higher term %d vs. %d, following %s", site_string(sender), term, tk->current_term, ticket_leader_string(tk)); } else { tk_log_debug("from %s: higher term %d vs. %d (election)", site_string(sender), term, tk->current_term); } tk->current_term = term; return 1; } return 0; } static int msg_term_invalid(struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg) { uint32_t term; term = ntohl(msg->ticket.term); /* §5.1 */ if (is_term_invalid(tk, term)) { tk_log_info("got invalid term from %s " - "(%d vs. %d), ignoring", site_string(sender), - term, tk->last_valid_tk->current_term); + "(%d), ignoring", site_string(sender), term); return 1; } return 0; } static int term_too_low(struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg) { uint32_t term; term = ntohl(msg->ticket.term); /* §5.1 */ if (term < tk->current_term) { tk_log_info("sending reject to %s, its term too low " "(%d vs. %d)", site_string(sender), term, tk->current_term ); send_reject(sender, tk, RLT_TERM_OUTDATED, msg); return 1; } return 0; } /* For follower. */ static int answer_HEARTBEAT ( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { uint32_t term; term = ntohl(msg->ticket.term); tk_log_debug("heartbeat from leader: %s, have %s; term %d vs %d", site_string(leader), ticket_leader_string(tk), term, tk->current_term); if (term < tk->current_term) { if (sender == tk->leader) { tk_log_info("trusting leader %s with a lower term (%d vs %d)", site_string(leader), term, tk->current_term); } else if (is_owned(tk)) { tk_log_warn("different leader %s with a lower term " "(%d vs %d), sending reject", site_string(leader), term, tk->current_term); return send_reject(sender, tk, RLT_TERM_OUTDATED, msg); } } /* got heartbeat, no rejects expected anymore */ tk->expect_more_rejects = 0; /* Needed? */ newer_term(tk, sender, leader, msg, 0); become_follower(tk, msg); /* Racy??? */ assert(sender == leader || !leader); set_leader(tk, leader); /* Ack the heartbeat (we comply). */ return send_msg(OP_ACK, tk, sender, msg); } static int process_UPDATE ( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { if (is_owned(tk) && sender != tk->leader) { tk_log_warn("different leader %s wants to update " "our ticket, sending reject", site_string(leader)); return send_reject(sender, tk, RLT_TERM_OUTDATED, msg); } tk_log_debug("leader %s wants to update our ticket", site_string(leader)); become_follower(tk, msg); set_leader(tk, leader); ticket_write(tk); /* run ticket_cron if the ticket expires */ set_ticket_wakeup(tk); return send_msg(OP_ACK, tk, sender, msg); } static int process_REVOKE ( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { int rv; if (tk->state == ST_INIT && tk->leader == no_leader) { /* assume that our ack got lost */ rv = send_msg(OP_ACK, tk, sender, msg); } else if (tk->leader != sender) { tk_log_error("%s wants to revoke ticket, " "but it is not granted there (ignoring)", site_string(sender)); return 1; } else if (tk->state != ST_FOLLOWER) { tk_log_error("unexpected ticket revoke from %s " "(in state %s) (ignoring)", site_string(sender), state_to_string(tk->state)); return 1; } else { tk_log_info("%s revokes ticket", site_string(tk->leader)); save_committed_tkt(tk); reset_ticket(tk); set_leader(tk, no_leader); ticket_write(tk); rv = send_msg(OP_ACK, tk, sender, msg); } return rv; } /* For leader. */ static int process_ACK( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { uint32_t term; int req; term = ntohl(msg->ticket.term); if (newer_term(tk, sender, leader, msg, 0)) { /* unexpected higher term */ tk_log_warn("got higher term from %s (%d vs. %d)", site_string(sender), term, tk->current_term); return 0; } /* Don't send a reject. */ if (term < tk->current_term) { /* Doesn't know what he's talking about - perhaps * doesn't receive our packets? */ tk_log_warn("unexpected term " "from %s (%d vs. %d) (ignoring)", site_string(sender), term, tk->current_term); return 0; } /* if the ticket is to be revoked, further processing is not * interesting (and dangerous) */ if (tk->next_state == ST_INIT || tk->state == ST_INIT) return 0; req = ntohl(msg->header.request); if ((req == OP_UPDATE || req == OP_HEARTBEAT) && term == tk->current_term && leader == tk->leader) { if (majority_of_bits(tk, tk->acks_received)) { /* OK, at least half of the nodes are reachable; * Update the ticket and send update messages out */ return leader_update_ticket(tk); } } return 0; } static int process_VOTE_FOR( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { if (leader == no_leader) { /* leader wants to step down? */ if (sender == tk->leader && (tk->state == ST_FOLLOWER || tk->state == ST_CANDIDATE)) { tk_log_info("%s wants to give the ticket away (ticket release)", site_string(tk->leader)); save_committed_tkt(tk); reset_ticket(tk); set_state(tk, ST_FOLLOWER); if (local->type == SITE) { ticket_write(tk); schedule_election(tk, OR_STEPDOWN); } } else { tk_log_info("%s votes for none, ignoring (duplicate ticket release?)", site_string(sender)); } return 0; } if (tk->state != ST_CANDIDATE) { /* lost candidate status, somebody rejected our proposal */ tk_log_info("candidate status lost, ignoring VtFr from %s", site_string(sender)); return 0; } if (term_too_low(tk, sender, leader, msg)) return 0; if (newer_term(tk, sender, leader, msg, 0)) { clear_election(tk); } record_vote(tk, sender, leader); /* only if all voted can we take the ticket now, otherwise * wait for timeout in ticket_cron */ if (!tk->acks_expected) { /* §5.2 */ elections_end(tk); } return 0; } static int process_REJECTED( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { uint32_t rv; rv = ntohl(msg->header.result); if (tk->state == ST_CANDIDATE && leader == local) { /* the sender has us as the leader (!) * the elections will time out, then we can try again */ tk_log_warn("ticket was granted to us " "(and we didn't know)"); tk->expect_more_rejects = 1; return 0; } if (tk->state == ST_CANDIDATE && rv == RLT_TERM_OUTDATED) { tk_log_warn("ticket outdated (term %d), granted to %s", ntohl(msg->ticket.term), site_string(leader) ); set_leader(tk, leader); tk->expect_more_rejects = 1; become_follower(tk, msg); return 0; } if (tk->state == ST_CANDIDATE && rv == RLT_TERM_STILL_VALID) { if (tk->lost_leader == leader) { if (tk->election_reason == OR_TKT_LOST) { tk_log_warn("%s still has the ticket valid, " "we'll backup a bit", site_string(sender)); } else { tk_log_warn("%s unexpectedly rejects elections", site_string(sender)); } } else { tk_log_warn("ticket was granted to %s " "(and we didn't know)", site_string(leader)); } set_leader(tk, leader); become_follower(tk, msg); tk->expect_more_rejects = 1; return 0; } if (tk->state == ST_CANDIDATE && rv == RLT_YOU_OUTDATED) { set_leader(tk, leader); tk->expect_more_rejects = 1; if (leader && leader != no_leader) { tk_log_warn("our ticket is outdated, granted to %s", site_string(leader)); become_follower(tk, msg); } else { tk_log_warn("our ticket is outdated and revoked"); update_ticket_from_msg(tk, sender, msg); set_state(tk, ST_INIT); } return 0; } if (!tk->expect_more_rejects) { tk_log_warn("from %s: in state %s, got %s (unexpected reject)", site_string(sender), state_to_string(tk->state), state_to_string(rv)); } return 0; } static int ticket_seems_ok(struct ticket_config *tk) { int left; left = term_time_left(tk); if (!left) return 0; /* quite sure */ if (tk->state == ST_CANDIDATE) return 0; /* in state of flux */ if (tk->state == ST_LEADER) return 1; /* quite sure */ if (tk->state == ST_FOLLOWER && left >= tk->term_duration/3) return 1; /* almost quite sure */ return 0; } static int test_reason( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { int reason; reason = ntohl(msg->header.reason); if (reason == OR_TKT_LOST) { if (tk->state == ST_INIT && tk->leader == no_leader) { tk_log_warn("%s claims that the ticket is lost, " "but it's in %s state (reject sent)", site_string(sender), state_to_string(tk->state) ); return RLT_YOU_OUTDATED; } if (ticket_seems_ok(tk)) { tk_log_warn("%s claims that the ticket is lost, " "but it is ok here (reject sent)", site_string(sender)); return RLT_TERM_STILL_VALID; } } return 0; } /* §5.2 */ static int answer_REQ_VOTE( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { int valid; struct boothc_ticket_msg omsg; cmd_result_t inappr_reason; int reason; inappr_reason = test_reason(tk, sender, leader, msg); if (inappr_reason) return send_reject(sender, tk, inappr_reason, msg); valid = term_time_left(tk); reason = ntohl(msg->header.reason); /* valid tickets are not allowed only if the sender thinks * the ticket got lost */ if (sender != tk->leader && valid && reason != OR_STEPDOWN) { tk_log_warn("election from %s with reason %s rejected " "(we have %s as ticket owner), ticket still valid for %ds", site_string(sender), state_to_string(reason), site_string(tk->leader), valid); return send_reject(sender, tk, RLT_TERM_STILL_VALID, msg); } if (term_too_low(tk, sender, leader, msg)) return 0; /* set this, so that we know not to send status for the * ticket */ tk->in_election = 1; /* reset ticket's leader on not valid tickets */ if (!valid) set_leader(tk, NULL); /* if it's a newer term or ... */ if (newer_term(tk, sender, leader, msg, 1)) { clear_election(tk); goto vote_for_sender; } /* ... we didn't vote yet, then vote for the sender */ /* §5.2, §5.4 */ if (!tk->voted_for) { vote_for_sender: tk->voted_for = sender; record_vote(tk, sender, leader); } init_ticket_msg(&omsg, OP_VOTE_FOR, OP_REQ_VOTE, RLT_SUCCESS, 0, tk); omsg.ticket.leader = htonl(get_node_id(tk->voted_for)); return booth_udp_send_auth(sender, &omsg, sendmsglen(&omsg)); } #define is_reason(r, tk) \ (reason == (r) || (reason == OR_AGAIN && (tk)->election_reason == (r))) int new_election(struct ticket_config *tk, struct booth_site *preference, int update_term, cmd_reason_t reason) { struct booth_site *new_leader; if (local->type != SITE) return 0; if ((is_reason(OR_TKT_LOST, tk) || is_reason(OR_STEPDOWN, tk)) && check_attr_prereq(tk, GRANT_AUTO)) { tk_log_info("attribute prerequisite not met, " "not starting elections"); return 0; } /* elections were already started, but not yet finished/timed out */ if (is_time_set(&tk->election_end) && !is_past(&tk->election_end)) return 1; if (ANYDEBUG) { int tdiff; if (is_time_set(&tk->election_end)) { tdiff = -time_left(&tk->election_end); tk_log_debug("starting elections, previous finished since " intfmt(tdiff)); } else { tk_log_debug("starting elections"); } tk_log_debug("elections caused by %s %s", state_to_string(reason), reason == OR_AGAIN ? state_to_string(tk->election_reason) : "" ); } /* §5.2 */ /* If there was _no_ answer, don't keep incrementing the term number * indefinitely. If there was no peer, there'll probably be no one * listening now either. However, we don't know if we were * invoked due to a timeout (caller does). */ /* increment the term only if either the current term was * valid or if there was a tie (in that case update_term > 1) */ if ((update_term > 1) || - (update_term && tk->last_valid_tk->current_term && + (update_term && tk->last_valid_tk && tk->last_valid_tk->current_term >= tk->current_term)) { /* save the previous term, we may need to send out the * MY_INDEX message */ if (tk->state != ST_CANDIDATE) { save_committed_tkt(tk); } tk->current_term++; } set_future_time(&tk->election_end, tk->timeout); tk->in_election = 1; tk_log_info("starting new election (term=%d)", tk->current_term); clear_election(tk); if(preference) new_leader = preference; else new_leader = (local->type == SITE) ? local : NULL; record_vote(tk, local, new_leader); tk->voted_for = new_leader; set_state(tk, ST_CANDIDATE); /* some callers may want just to repeat on timeout */ if (reason == OR_AGAIN) { reason = tk->election_reason; } else { tk->election_reason = reason; } ticket_broadcast(tk, OP_REQ_VOTE, OP_VOTE_FOR, RLT_SUCCESS, reason); add_random_delay(tk); return 0; } /* we were a leader and somebody says that they have a more up * to date ticket * there was probably connectivity loss * tricky */ static int leader_handle_newer_ticket( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { update_term_from_msg(tk, msg); if (leader != no_leader && leader && leader != local) { /* eek, two leaders, split brain */ /* normally shouldn't happen; run election */ tk_log_error("from %s: ticket granted to %s! (revoking locally)", site_string(sender), site_string(leader) ); } else if (term_time_left(tk)) { /* eek, two leaders, split brain */ /* normally shouldn't happen; run election */ tk_log_error("from %s: ticket granted to %s! (revoking locally)", site_string(sender), site_string(leader) ); } set_next_state(tk, ST_LEADER); return 0; } /* reply to STATUS */ static int process_MY_INDEX ( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { int i; int expired; expired = !msg_term_time(msg); /* test against the last valid(!) ticket we have */ i = my_last_term(tk) - ntohl(msg->ticket.term); if (i > 0) { /* let them know about our newer ticket */ send_msg(OP_MY_INDEX, tk, sender, msg); if (tk->state == ST_LEADER) { tk_log_info("sending ticket update to %s", site_string(sender)); return send_msg(OP_UPDATE, tk, sender, msg); } } /* we have a newer or equal ticket and theirs is expired, * nothing more to do here */ if (i >= 0 && expired) { return 0; } if (tk->state == ST_LEADER) { /* we're the leader, thread carefully */ if (expired) { /* if their ticket is expired, * nothing more to do */ return 0; } if (i < 0) { /* they have a newer ticket, trouble if we're already leader * for it */ tk_log_warn("from %s: more up to date ticket at %s", site_string(sender), site_string(leader) ); return leader_handle_newer_ticket(tk, sender, leader, msg); } else { /* we have the ticket and we don't care */ return 0; } } else if (tk->state == ST_CANDIDATE) { if (leader == local) { /* a belated MY_INDEX, we're already trying to get the * ticket */ return 0; } } /* their ticket is either newer or not expired, don't * ignore it */ update_ticket_from_msg(tk, sender, msg); set_leader(tk, leader); update_ticket_state(tk, sender); save_committed_tkt(tk); set_ticket_wakeup(tk); return 0; } int raft_answer( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { int cmd, req; int rv; rv = 0; cmd = ntohl(msg->header.cmd); req = ntohl(msg->header.request); if (req) tk_log_debug("got %s (req %s) from %s", state_to_string(cmd), state_to_string(req), site_string(sender)); else tk_log_debug("got %s from %s", state_to_string(cmd), site_string(sender)); /* don't process tickets with invalid term */ if (cmd != OP_STATUS && msg_term_invalid(tk, sender, leader, msg)) return 0; switch (cmd) { case OP_REQ_VOTE: rv = answer_REQ_VOTE(tk, sender, leader, msg); break; case OP_VOTE_FOR: rv = process_VOTE_FOR(tk, sender, leader, msg); break; case OP_ACK: if (tk->leader == local && tk->state == ST_LEADER) rv = process_ACK(tk, sender, leader, msg); break; case OP_HEARTBEAT: if ((tk->leader != local || !term_time_left(tk)) && (tk->state == ST_INIT || tk->state == ST_FOLLOWER || tk->state == ST_CANDIDATE)) rv = answer_HEARTBEAT(tk, sender, leader, msg); else { tk_log_warn("unexpected message %s, from %s", state_to_string(cmd), site_string(sender)); if (ticket_seems_ok(tk)) send_reject(sender, tk, RLT_TERM_STILL_VALID, msg); rv = -EINVAL; } break; case OP_UPDATE: if (((tk->leader != local && tk->leader == leader) || !is_owned(tk)) && (tk->state == ST_INIT || tk->state == ST_FOLLOWER || tk->state == ST_CANDIDATE)) { rv = process_UPDATE(tk, sender, leader, msg); } else { tk_log_warn("unexpected message %s, from %s", state_to_string(cmd), site_string(sender)); if (ticket_seems_ok(tk)) send_reject(sender, tk, RLT_TERM_STILL_VALID, msg); rv = -EINVAL; } break; case OP_REJECTED: rv = process_REJECTED(tk, sender, leader, msg); break; case OP_REVOKE: rv = process_REVOKE(tk, sender, leader, msg); break; case OP_MY_INDEX: rv = process_MY_INDEX(tk, sender, leader, msg); break; case OP_STATUS: if (!tk->in_election) rv = send_msg(OP_MY_INDEX, tk, sender, msg); break; default: tk_log_error("unknown message %s, from %s", state_to_string(cmd), site_string(sender)); rv = -EINVAL; } return rv; } diff --git a/src/ticket.c b/src/ticket.c index 061095c..ab85887 100644 --- a/src/ticket.c +++ b/src/ticket.c @@ -1,1320 +1,1333 @@ /* * Copyright (C) 2011 Jiaju Zhang * Copyright (C) 2013-2014 Philipp Marek * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include #include #include #include #include #include #include #include "b_config.h" #include "ticket.h" #include "config.h" #include "pacemaker.h" #include "inline-fn.h" #include "log.h" #include "booth.h" #include "raft.h" #include "handler.h" #include "request.h" #define TK_LINE 256 extern int TIME_RES; /* Untrusted input, must fit (incl. \0) in a buffer of max chars. */ int check_max_len_valid(const char *s, int max) { int i; for(i=0; iticket_count; i++) { if (!strcmp(booth_conf->ticket[i].name, ticket)) { if (found) *found = booth_conf->ticket + i; return 1; } } return 0; } int check_ticket(char *ticket, struct ticket_config **found) { if (found) *found = NULL; if (!booth_conf) return 0; if (!check_max_len_valid(ticket, sizeof(booth_conf->ticket[0].name))) return 0; return find_ticket_by_name(ticket, found); } int check_site(char *site, int *is_local) { struct booth_site *node; if (!check_max_len_valid(site, sizeof(node->addr_string))) return 0; if (find_site_by_name(site, &node, 0)) { *is_local = node->local; return 1; } return 0; } /* is it safe to commit the grant? * if we didn't hear from all sites on the initial grant, we may * need to delay the commit * * TODO: investigate possibility to devise from history whether a * missing site could be holding a ticket or not */ static int ticket_dangerous(struct ticket_config *tk) { int tdiff; /* we may be invoked often, don't spam the log unnecessarily */ static int no_log_delay_msg; if (!is_time_set(&tk->delay_commit)) return 0; if (is_past(&tk->delay_commit) || all_sites_replied(tk)) { if (tk->leader == local) { tk_log_info("%s, committing to CIB", is_past(&tk->delay_commit) ? "ticket delay expired" : "all sites replied"); } time_reset(&tk->delay_commit); no_log_delay_msg = 0; return 0; } tdiff = time_left(&tk->delay_commit); tk_log_debug("delay ticket commit for another " intfmt(tdiff)); if (!no_log_delay_msg) { tk_log_info("delaying ticket commit to CIB for " intfmt(tdiff)); tk_log_info("(or all sites are reached)"); no_log_delay_msg = 1; } return 1; } int ticket_write(struct ticket_config *tk) { if (local->type != SITE) return -EINVAL; if (ticket_dangerous(tk)) return 1; if (tk->leader == local) { if (tk->state != ST_LEADER) { tk_log_info("ticket state not yet consistent, " "delaying ticket grant to CIB"); return 1; } pcmk_handler.grant_ticket(tk); } else { pcmk_handler.revoke_ticket(tk); } tk->update_cib = 0; return 0; } +void save_committed_tkt(struct ticket_config *tk) +{ + if (!tk->last_valid_tk) { + tk->last_valid_tk = malloc(sizeof(struct ticket_config)); + if (!tk->last_valid_tk) { + log_error("out of memory"); + return; + } + } + memcpy(tk->last_valid_tk, tk, sizeof(struct ticket_config)); +} + + static void ext_prog_failed(struct ticket_config *tk, int start_election) { /* Give it to somebody else. * Just send a VOTE_FOR message, so the * others can start elections. */ if (leader_and_valid(tk)) { save_committed_tkt(tk); reset_ticket(tk); ticket_write(tk); if (start_election) { ticket_broadcast(tk, OP_VOTE_FOR, OP_REQ_VOTE, RLT_SUCCESS, OR_LOCAL_FAIL); } } } /* Ask an external program whether getting the ticket * makes sense. * Eg. if the services have a failcount of INFINITY, * we can't serve here anyway. */ static int run_external_prog(struct ticket_config *tk, int start_election) { int rv; rv = run_handler(tk); switch (rv) { case RUNCMD_ERR: tk_log_warn("couldn't run external test, not allowed to acquire ticket"); ext_prog_failed(tk, start_election); break; case 0: /* immediately returned with success */ break; case RUNCMD_MORE: tk_log_debug("forked %s", tk_test.prog); break; default: break; } return rv; } static int test_exit_status(struct ticket_config *tk, int start_election) { int rv = -1, status; status = tk_test.status; if (WIFEXITED(status)) { rv = WEXITSTATUS(status); } else if (WIFSIGNALED(status)) { rv = 128 + WTERMSIG(status); } if (rv) { tk_log_warn("handler \"%s\" failed: %s", tk_test.prog, interpret_rv(status)); tk_log_warn("we are not allowed to acquire ticket"); ext_prog_failed(tk, start_election); } else { tk_log_debug("handler \"%s\" exited with success", tk_test.prog); } tk_test.pid = 0; tk_test.progstate = EXTPROG_IDLE; return rv; } #define attr_found(geo_ap, ap) \ ((geo_ap) && !strcmp((geo_ap)->val, (ap)->attr_val)) int check_attr_prereq(struct ticket_config *tk, grant_type_e grant_type) { GList *el; struct attr_prereq *ap; struct geo_attr *geo_ap; for (el = g_list_first(tk->attr_prereqs); el; el = g_list_next(el)) { ap = (struct attr_prereq *)el->data; if (ap->grant_type != grant_type) continue; geo_ap = (struct geo_attr *)g_hash_table_lookup(tk->attr, ap->attr_name); switch(ap->op) { case ATTR_OP_EQ: if (!attr_found(geo_ap, ap)) goto fail; break; case ATTR_OP_NE: if (attr_found(geo_ap, ap)) goto fail; break; default: break; } } return 0; fail: tk_log_warn("'%s' attr-prereq failed", ap->attr_name); return 1; } /* do we need to run the external program? * or we already done that and waiting for the outcome * or program exited and we can collect the status * return codes * 0: no program defined * RUNCMD_MORE: program forked, results later * != 0: executing program failed (or some other failure) */ static int do_ext_prog(struct ticket_config *tk, int start_election) { int rv = 0; if (!tk_test.prog) return 0; switch(tk_test.progstate) { case EXTPROG_IDLE: rv = run_external_prog(tk, start_election); break; case EXTPROG_RUNNING: /* should never get here, but just in case */ rv = RUNCMD_MORE; break; case EXTPROG_EXITED: rv = test_exit_status(tk, start_election); break; case EXTPROG_IGNORE: /* nothing to do here */ break; } return rv; } /* Try to acquire a ticket * Could be manual grant or after start (if the ticket is granted * and still valid in the CIB) * If the external program needs to run, this is run twice, once * to start the program, and then to get the result and start * elections. */ int acquire_ticket(struct ticket_config *tk, cmd_reason_t reason) { int rv; if (reason == OR_ADMIN && check_attr_prereq(tk, GRANT_MANUAL)) return RLT_ATTR_PREREQ; switch(do_ext_prog(tk, 0)) { case 0: /* everything fine */ break; case RUNCMD_MORE: /* need to wait for the outcome before starting elections */ return 0; default: return RLT_EXT_FAILED; } rv = new_election(tk, local, 1, reason); return rv ? RLT_SYNC_FAIL : 0; } /** Try to get the ticket for the local site. * */ int do_grant_ticket(struct ticket_config *tk, int options) { int rv; tk_log_info("granting ticket"); if (tk->leader == local) return RLT_SUCCESS; if (is_owned(tk)) return RLT_OVERGRANT; set_future_time(&tk->delay_commit, tk->term_duration + tk->acquire_after); if (options & OPT_IMMEDIATE) { tk_log_warn("granting ticket immediately! If there are " "unreachable sites, _hope_ you are sure that they don't " "have the ticket!"); time_reset(&tk->delay_commit); } rv = acquire_ticket(tk, OR_ADMIN); if (rv) { time_reset(&tk->delay_commit); return rv; } else { return RLT_MORE; } } static void ignore_extprog(struct ticket_config *tk) { if (tk_test.prog && tk_test.pid >= 0 && tk_test.progstate == EXTPROG_RUNNING) { tk_test.progstate = EXTPROG_IGNORE; (void)kill(tk_test.pid, SIGTERM); } } static void start_revoke_ticket(struct ticket_config *tk) { tk_log_info("revoking ticket"); save_committed_tkt(tk); reset_ticket(tk); set_leader(tk, no_leader); ignore_extprog(tk); ticket_write(tk); ticket_broadcast(tk, OP_REVOKE, OP_ACK, RLT_SUCCESS, OR_ADMIN); } /** Ticket revoke. * Only to be started from the leader. */ int do_revoke_ticket(struct ticket_config *tk) { if (tk->acks_expected) { tk_log_info("delay ticket revoke until the current operation finishes"); set_next_state(tk, ST_INIT); return RLT_MORE; } else { start_revoke_ticket(tk); return RLT_SUCCESS; } } int list_ticket(char **pdata, unsigned int *len) { struct ticket_config *tk; char timeout_str[64]; char pending_str[64]; char *data, *cp; int i, alloc; time_t ts; *pdata = NULL; *len = 0; alloc = 256 + booth_conf->ticket_count * (BOOTH_NAME_LEN * 2 + 128); data = malloc(alloc); if (!data) return -ENOMEM; cp = data; foreach_ticket(i, tk) { if (is_time_set(&tk->term_expires)) { ts = wall_ts(&tk->term_expires); strftime(timeout_str, sizeof(timeout_str), "%F %T", localtime(&ts)); } else strcpy(timeout_str, "INF"); if (tk->leader == local && is_time_set(&tk->delay_commit) && !is_past(&tk->delay_commit)) { ts = wall_ts(&tk->delay_commit); strcpy(pending_str, " (commit pending until "); strftime(pending_str + strlen(" (commit pending until "), sizeof(pending_str) - strlen(" (commit pending until ") - 1, "%F %T", localtime(&ts)); strcat(pending_str, ")"); } else *pending_str = '\0'; cp += snprintf(cp, alloc - (cp - data), "ticket: %s, leader: %s", tk->name, ticket_leader_string(tk)); if (is_owned(tk)) { cp += snprintf(cp, alloc - (cp - data), ", expires: %s%s\n", timeout_str, pending_str); } else { cp += snprintf(cp, alloc - (cp - data), "\n"); } if (alloc - (cp - data) <= 0) return -ENOMEM; } *pdata = data; *len = cp - data; return 0; } void disown_ticket(struct ticket_config *tk) { set_leader(tk, NULL); tk->is_granted = 0; get_time(&tk->term_expires); } int disown_if_expired(struct ticket_config *tk) { if (is_past(&tk->term_expires) || !tk->leader) { disown_ticket(tk); return 1; } return 0; } void reset_ticket(struct ticket_config *tk) { disown_ticket(tk); no_resends(tk); set_state(tk, ST_INIT); tk->voted_for = NULL; } static void log_reacquire_reason(struct ticket_config *tk) { int valid; const char *where_granted = "\0"; char buff[64]; valid = is_time_set(&tk->term_expires) && !is_past(&tk->term_expires); if (tk->leader == local) { where_granted = "granted here"; } else { snprintf(buff, sizeof(buff), "granted to %s", site_string(tk->leader)); where_granted = buff; } if (!valid) { tk_log_warn("%s, but not valid " "anymore (will try to reacquire)", where_granted); } if (tk->is_granted && tk->leader != local) { if (tk->leader && tk->leader != no_leader) { tk_log_error("granted here, but also %s, " "that's really too bad (will try to reacquire)", where_granted); } else { tk_log_warn("granted here, but we're " "not recorded as the grantee (will try to reacquire)"); } } } void update_ticket_state(struct ticket_config *tk, struct booth_site *sender) { if (tk->state == ST_CANDIDATE) { tk_log_info("learned from %s about " "newer ticket, stopping elections", site_string(sender)); /* there could be rejects coming from others; don't log * warnings unnecessarily */ tk->expect_more_rejects = 1; } if (tk->leader == local || tk->is_granted) { /* message from a live leader with valid ticket? */ if (sender == tk->leader && term_time_left(tk)) { if (tk->is_granted) { tk_log_warn("ticket was granted here, " "but it's live at %s (revoking here)", site_string(sender)); } else { tk_log_info("ticket live at %s", site_string(sender)); } disown_ticket(tk); ticket_write(tk); set_state(tk, ST_FOLLOWER); set_next_state(tk, ST_FOLLOWER); } else { if (tk->state == ST_CANDIDATE) { set_state(tk, ST_FOLLOWER); } set_next_state(tk, ST_LEADER); } } else { if (!tk->leader || tk->leader == no_leader) { if (sender) tk_log_info("ticket is not granted"); else tk_log_info("ticket is not granted (from CIB)"); set_state(tk, ST_INIT); } else { if (sender) tk_log_info("ticket granted to %s (says %s)", site_string(tk->leader), tk->leader == sender ? "they" : site_string(sender)); else tk_log_info("ticket granted to %s (from CIB)", site_string(tk->leader)); set_state(tk, ST_FOLLOWER); /* just make sure that we check the ticket soon */ set_next_state(tk, ST_FOLLOWER); } } } int setup_ticket(void) { struct ticket_config *tk; int i; foreach_ticket(i, tk) { reset_ticket(tk); if (local->type == SITE) { if (!pcmk_handler.load_ticket(tk)) { update_ticket_state(tk, NULL); } tk->update_cib = 1; } tk_log_info("broadcasting state query"); /* wait until all send their status (or the first * timeout) */ tk->start_postpone = 1; ticket_broadcast(tk, OP_STATUS, OP_MY_INDEX, RLT_SUCCESS, 0); } return 0; } int ticket_answer_list(int fd) { char *data; int olen, rv; struct boothc_hdr_msg hdr; rv = list_ticket(&data, &olen); if (rv < 0) goto out; init_header(&hdr.header, CL_LIST, 0, 0, RLT_SUCCESS, 0, sizeof(hdr) + olen); rv = send_header_plus(fd, &hdr, data, olen); out: if (data) free(data); return rv; } int process_client_request(struct client *req_client, void *buf) { int rv, rc = 1; struct ticket_config *tk; int cmd; struct boothc_ticket_msg omsg; struct boothc_ticket_msg *msg; msg = (struct boothc_ticket_msg *)buf; cmd = ntohl(msg->header.cmd); if (!check_ticket(msg->ticket.id, &tk)) { log_warn("client referenced unknown ticket %s", msg->ticket.id); rv = RLT_INVALID_ARG; goto reply_now; } if ((cmd == CMD_GRANT) && is_owned(tk)) { log_warn("client wants to grant an (already granted!) ticket %s", msg->ticket.id); rv = RLT_OVERGRANT; goto reply_now; } if ((cmd == CMD_REVOKE) && !is_owned(tk)) { log_info("client wants to revoke a free ticket %s", msg->ticket.id); rv = RLT_TICKET_IDLE; goto reply_now; } if ((cmd == CMD_REVOKE) && tk->leader != local) { tk_log_info("not granted here, redirect to %s", ticket_leader_string(tk)); rv = RLT_REDIRECT; goto reply_now; } if (cmd == CMD_REVOKE) rv = do_revoke_ticket(tk); else rv = do_grant_ticket(tk, ntohl(msg->header.options)); if (rv == RLT_MORE) { /* client may receive further notifications, save the * request for further processing */ add_req(tk, req_client, msg); tk_log_debug("queue request %s for client %d", state_to_string(cmd), req_client->fd); rc = 0; /* we're not yet done with the message */ } reply_now: init_ticket_msg(&omsg, CL_RESULT, 0, rv, 0, tk); send_client_msg(req_client->fd, &omsg); return rc; } int notify_client(struct ticket_config *tk, int client_fd, struct boothc_ticket_msg *msg) { struct boothc_ticket_msg omsg; void (*deadfn) (int ci); int rv, rc, ci; int cmd, options; struct client *req_client; cmd = ntohl(msg->header.cmd); options = ntohl(msg->header.options); rv = tk->outcome; ci = find_client_by_fd(client_fd); if (ci < 0) { tk_log_info("client %d (request %s) left before being notified", client_fd, state_to_string(cmd)); return 0; } tk_log_debug("notifying client %d (request %s)", client_fd, state_to_string(cmd)); init_ticket_msg(&omsg, CL_RESULT, 0, rv, 0, tk); rc = send_client_msg(client_fd, &omsg); if (rc == 0 && ((rv == RLT_MORE) || (rv == RLT_CIB_PENDING && (options & OPT_WAIT_COMMIT)))) { /* more to do here, keep the request */ return 1; } else { /* we sent a definite answer or there was a write error, drop * the client */ if (rc) { tk_log_debug("failed to notify client %d (request %s)", client_fd, state_to_string(cmd)); } else { tk_log_debug("client %d (request %s) got final notification", client_fd, state_to_string(cmd)); } req_client = clients + ci; deadfn = req_client->deadfn; if(deadfn) { deadfn(ci); } return 0; /* we're done with this request */ } } int ticket_broadcast(struct ticket_config *tk, cmd_request_t cmd, cmd_request_t expected_reply, cmd_result_t res, cmd_reason_t reason) { struct boothc_ticket_msg msg; init_ticket_msg(&msg, cmd, 0, res, reason, tk); tk_log_debug("broadcasting '%s' (term=%d, valid=%d)", state_to_string(cmd), ntohl(msg.ticket.term), msg_term_time(&msg)); tk->last_request = cmd; if (expected_reply) { expect_replies(tk, expected_reply); } ticket_activate_timeout(tk); return transport()->broadcast_auth(&msg, sendmsglen(&msg)); } /* update the ticket on the leader, write it to the CIB, and send out the update message to others with the new expiry time */ int leader_update_ticket(struct ticket_config *tk) { int rv = 0, rv2; timetype now; if (tk->ticket_updated >= 2) return 0; if (tk->ticket_updated < 1) { tk->ticket_updated = 1; get_time(&now); copy_time(&now, &tk->last_renewal); set_future_time(&tk->term_expires, tk->term_duration); rv = ticket_broadcast(tk, OP_UPDATE, OP_ACK, RLT_SUCCESS, 0); } if (tk->ticket_updated < 2) { rv2 = ticket_write(tk); switch(rv2) { case 0: tk->ticket_updated = 2; tk->outcome = RLT_SUCCESS; foreach_tkt_req(tk, notify_client); break; case 1: if (tk->outcome != RLT_CIB_PENDING) { tk->outcome = RLT_CIB_PENDING; foreach_tkt_req(tk, notify_client); } break; default: break; } } return rv; } static void log_lost_servers(struct ticket_config *tk) { struct booth_site *n; int i; if (tk->retry_number > 1) /* log those that we couldn't reach, but do * that only on the first retry */ return; for (i = 0; i < booth_conf->site_count; i++) { n = booth_conf->site + i; if (!(tk->acks_received & n->bitmask)) { tk_log_warn("%s %s didn't acknowledge our %s, " "will retry %d times", (n->type == ARBITRATOR ? "arbitrator" : "site"), site_string(n), state_to_string(tk->last_request), tk->retries); } } } static void resend_msg(struct ticket_config *tk) { struct booth_site *n; int i; if (!(tk->acks_received ^ local->bitmask)) { ticket_broadcast(tk, tk->last_request, 0, RLT_SUCCESS, 0); } else { for (i = 0; i < booth_conf->site_count; i++) { n = booth_conf->site + i; if (!(tk->acks_received & n->bitmask)) { n->resend_cnt++; tk_log_debug("resending %s to %s", state_to_string(tk->last_request), site_string(n) ); send_msg(tk->last_request, tk, n, NULL); } } ticket_activate_timeout(tk); } } static void handle_resends(struct ticket_config *tk) { int ack_cnt; if (++tk->retry_number > tk->retries) { tk_log_info("giving up on sending retries"); no_resends(tk); set_ticket_wakeup(tk); return; } /* try to reach some sites again if we just stepped down */ if (tk->last_request == OP_VOTE_FOR) { tk_log_warn("no answers to our VtFr request to step down (try #%d), " "we are alone", tk->retry_number); goto just_resend; } if (!majority_of_bits(tk, tk->acks_received)) { ack_cnt = count_bits(tk->acks_received) - 1; if (!ack_cnt) { tk_log_warn("no answers to our request (try #%d), " "we are alone", tk->retry_number); } else { tk_log_warn("not enough answers to our request (try #%d): " "only got %d answers", tk->retry_number, ack_cnt); } } else { log_lost_servers(tk); } just_resend: resend_msg(tk); } int postpone_ticket_processing(struct ticket_config *tk) { extern timetype start_time; return tk->start_postpone && (-time_left(&start_time) < tk->timeout); } #define has_extprog_exited(tk) ((tk)->clu_test.progstate == EXTPROG_EXITED) static void process_next_state(struct ticket_config *tk) { int rv; switch(tk->next_state) { case ST_LEADER: if (has_extprog_exited(tk)) { if (tk->state != ST_LEADER) { rv = acquire_ticket(tk, OR_ADMIN); if (rv != 0) { /* external program failed */ tk->outcome = rv; foreach_tkt_req(tk, notify_client); } } } else { log_reacquire_reason(tk); acquire_ticket(tk, OR_REACQUIRE); } break; case ST_INIT: no_resends(tk); start_revoke_ticket(tk); tk->outcome = RLT_SUCCESS; foreach_tkt_req(tk, notify_client); break; /* wanting to be follower is not much of an ambition; no * processing, just return; don't reset start_postpone until * we got some replies to status */ case ST_FOLLOWER: return; default: break; } tk->start_postpone = 0; } static void ticket_lost(struct ticket_config *tk) { int reason = OR_TKT_LOST; if (tk->leader != local) { tk_log_warn("lost at %s", site_string(tk->leader)); } else { tk_log_warn("lost majority (revoking locally)"); reason = tk->election_reason ? tk->election_reason : OR_REACQUIRE; } tk->lost_leader = tk->leader; save_committed_tkt(tk); reset_ticket(tk); set_state(tk, ST_FOLLOWER); if (local->type == SITE) { ticket_write(tk); schedule_election(tk, reason); } } static void next_action(struct ticket_config *tk) { int rv; switch(tk->state) { case ST_INIT: /* init state, handle resends for ticket revoke */ /* and rebroadcast if stepping down */ /* try to acquire ticket on grant */ if (has_extprog_exited(tk)) { rv = acquire_ticket(tk, OR_ADMIN); if (rv != 0) { /* external program failed */ tk->outcome = rv; foreach_tkt_req(tk, notify_client); } } else { if (tk->acks_expected) { handle_resends(tk); } } break; case ST_FOLLOWER: /* leader/ticket lost? and we didn't vote yet */ tk_log_debug("leader: %s, voted_for: %s", site_string(tk->leader), site_string(tk->voted_for)); if (!tk->leader) { if (!tk->voted_for || !tk->in_election) { disown_ticket(tk); if (!new_election(tk, NULL, 1, OR_AGAIN)) { ticket_activate_timeout(tk); } } else { /* we should restart elections in case nothing * happens in the meantime */ tk->in_election = 0; ticket_activate_timeout(tk); } } break; case ST_CANDIDATE: /* elections timed out? */ elections_end(tk); break; case ST_LEADER: /* timeout or ticket renewal? */ if (tk->acks_expected) { handle_resends(tk); if (majority_of_bits(tk, tk->acks_received)) { leader_update_ticket(tk); } } else { /* this is ticket renewal, run local test */ if (!do_ext_prog(tk, 1)) { ticket_broadcast(tk, OP_HEARTBEAT, OP_ACK, RLT_SUCCESS, 0); tk->ticket_updated = 0; } } break; default: break; } } static void ticket_cron(struct ticket_config *tk) { /* don't process the tickets too early after start */ if (postpone_ticket_processing(tk)) { tk_log_debug("ticket processing postponed (start_postpone=%d)", tk->start_postpone); /* but run again soon */ ticket_activate_timeout(tk); return; } /* no need for status resends, we hope we got at least one * my_index back */ if (tk->acks_expected == OP_MY_INDEX) { no_resends(tk); } /* after startup, we need to decide what to do based on the * current ticket state; tk->next_state has a hint * also used for revokes which had to be delayed */ if (tk->next_state) { process_next_state(tk); goto out; } /* Has an owner, has an expiry date, and expiry date in the past? * Losing the ticket must happen in _every_ state. */ if (is_owned(tk) && is_time_set(&tk->term_expires) && is_past(&tk->term_expires)) { ticket_lost(tk); goto out; } next_action(tk); out: tk->next_state = 0; if (!tk->in_election && tk->update_cib) ticket_write(tk); } void process_tickets(void) { struct ticket_config *tk; int i; timetype last_cron; foreach_ticket(i, tk) { if (!has_extprog_exited(tk) && is_time_set(&tk->next_cron) && !is_past(&tk->next_cron)) continue; tk_log_debug("ticket cron"); copy_time(&tk->next_cron, &last_cron); ticket_cron(tk); if (time_cmp(&last_cron, &tk->next_cron, ==)) { tk_log_debug("nobody set ticket wakeup"); set_ticket_wakeup(tk); } } } void tickets_log_info(void) { struct ticket_config *tk; int i; time_t ts; foreach_ticket(i, tk) { ts = wall_ts(&tk->term_expires); tk_log_info("state '%s' " "term %d " "leader %s " "expires %-24.24s", state_to_string(tk->state), tk->current_term, ticket_leader_string(tk), ctime(&ts)); } } static void update_acks( struct ticket_config *tk, struct booth_site *sender, struct booth_site *leader, struct boothc_ticket_msg *msg ) { uint32_t cmd; uint32_t req; cmd = ntohl(msg->header.cmd); req = ntohl(msg->header.request); if (req != tk->last_request || (tk->acks_expected != cmd && tk->acks_expected != OP_REJECTED)) return; /* got an ack! */ tk->acks_received |= sender->bitmask; if (all_replied(tk) || /* we just stepped down, need only one site to start * elections */ (cmd == OP_REQ_VOTE && tk->last_request == OP_VOTE_FOR)) { no_resends(tk); tk->start_postpone = 0; set_ticket_wakeup(tk); } } /* read ticket message */ int ticket_recv(void *buf, struct booth_site *source) { struct boothc_ticket_msg *msg; struct ticket_config *tk; struct booth_site *leader; uint32_t leader_u; msg = (struct boothc_ticket_msg *)buf; if (!check_ticket(msg->ticket.id, &tk)) { log_warn("got invalid ticket name %s from %s", msg->ticket.id, site_string(source)); source->invalid_cnt++; return -EINVAL; } leader_u = ntohl(msg->ticket.leader); if (!find_site_by_id(leader_u, &leader)) { tk_log_error("message with unknown leader %u received", leader_u); source->invalid_cnt++; return -EINVAL; } update_acks(tk, source, leader, msg); return raft_answer(tk, source, leader, msg); } static void log_next_wakeup(struct ticket_config *tk) { int left; left = time_left(&tk->next_cron); tk_log_debug("set ticket wakeup in " intfmt(left)); } /* New vote round; §5.2 */ /* delay the next election start for some random time * (up to 1 second) */ void add_random_delay(struct ticket_config *tk) { timetype tv; interval_add(&tk->next_cron, rand_time(min(1000, tk->timeout)), &tv); ticket_next_cron_at(tk, &tv); if (ANYDEBUG) { log_next_wakeup(tk); } } void set_ticket_wakeup(struct ticket_config *tk) { timetype near_future, tv, next_vote; /* At least every hour, perhaps sooner (default) */ ticket_next_cron_in(tk, 3600*TIME_RES); set_future_time(&near_future, 10); switch (tk->state) { case ST_LEADER: assert(tk->leader == local); get_next_election_time(tk, &next_vote); /* If timestamp is in the past, wakeup in * near future */ if (!is_time_set(&next_vote)) { tk_log_debug("next ts unset, wakeup soon"); ticket_next_cron_at(tk, &near_future); } else if (is_past(&next_vote)) { int tdiff = time_left(&next_vote); tk_log_debug("next ts in the past " intfmt(tdiff)); ticket_next_cron_at(tk, &near_future); } else { ticket_next_cron_at(tk, &next_vote); } break; case ST_CANDIDATE: assert(is_time_set(&tk->election_end)); ticket_next_cron_at(tk, &tk->election_end); break; case ST_INIT: case ST_FOLLOWER: /* If there is (or should be) some owner, check on it later on. * If no one is interested - don't care. */ if (is_owned(tk)) { interval_add(&tk->term_expires, tk->acquire_after, &tv); ticket_next_cron_at(tk, &tv); } break; default: tk_log_error("unknown ticket state: %d", tk->state); } if (tk->next_state) { /* we need to do something soon here */ if (!tk->acks_expected) { ticket_next_cron_at(tk, &near_future); } else { ticket_activate_timeout(tk); } } if (ANYDEBUG) { log_next_wakeup(tk); } } void schedule_election(struct ticket_config *tk, cmd_reason_t reason) { if (local->type != SITE) return; tk->election_reason = reason; get_time(&tk->next_cron); /* introduce a short delay before starting election */ add_random_delay(tk); } /* Given a state (in host byte order), return a human-readable (char*). * An array is used so that multiple states can be printed in a single printf(). */ char *state_to_string(uint32_t state_ho) { union mu { cmd_request_t s; char c[5]; }; static union mu cache[6] = { { 0 } }, *cur; static int current = 0; current ++; if (current >= sizeof(cache)/sizeof(cache[0])) current = 0; cur = cache + current; cur->s = htonl(state_ho); /* Shouldn't be necessary, union array is initialized with zeroes, and * these bytes never get written. */ cur->c[4] = 0; return cur->c; } int send_reject(struct booth_site *dest, struct ticket_config *tk, cmd_result_t code, struct boothc_ticket_msg *in_msg) { int req = ntohl(in_msg->header.cmd); struct boothc_ticket_msg msg; tk_log_debug("sending reject to %s", site_string(dest)); init_ticket_msg(&msg, OP_REJECTED, req, code, 0, tk); return booth_udp_send_auth(dest, &msg, sendmsglen(&msg)); } int send_msg ( int cmd, struct ticket_config *current_tk, struct booth_site *dest, struct boothc_ticket_msg *in_msg ) { int req = 0; struct ticket_config *tk = current_tk; struct boothc_ticket_msg msg; if (cmd == OP_MY_INDEX) { if (current_tk->state == ST_CANDIDATE && - current_tk->last_valid_tk->current_term) { + current_tk->last_valid_tk) { tk = current_tk->last_valid_tk; } tk_log_info("sending status to %s", site_string(dest)); } if (in_msg) req = ntohl(in_msg->header.cmd); init_ticket_msg(&msg, cmd, req, RLT_SUCCESS, 0, tk); return booth_udp_send_auth(dest, &msg, sendmsglen(&msg)); } diff --git a/src/ticket.h b/src/ticket.h index 9ae947a..1e1ffa9 100644 --- a/src/ticket.h +++ b/src/ticket.h @@ -1,133 +1,130 @@ /* * Copyright (C) 2011 Jiaju Zhang * Copyright (C) 2013-2014 Philipp Marek * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #ifndef _TICKET_H #define _TICKET_H #include #include #include #include "timer.h" #include "config.h" #include "log.h" extern int TIME_RES; #define DEFAULT_TICKET_EXPIRY (600*TIME_RES) #define DEFAULT_TICKET_TIMEOUT (5*TIME_RES) #define DEFAULT_RETRIES 10 #define foreach_ticket(i_,t_) for(i=0; (t_=booth_conf->ticket+i, iticket_count); i++) #define foreach_node(i_,n_) for(i=0; (n_=booth_conf->site+i, isite_count); i++) #define set_leader(tk, who) do { \ tk->leader = who; \ tk_log_debug("ticket leader set to %s", ticket_leader_string(tk)); \ } while(0) #define set_state(tk, newst) do { \ tk_log_debug("state transition: %s -> %s", \ state_to_string(tk->state), state_to_string(newst)); \ tk->state = newst; \ } while(0) #define set_next_state(tk, newst) do { \ if (!(newst)) tk_log_debug("next state reset"); \ else tk_log_debug("next state set to %s", state_to_string(newst)); \ tk->next_state = newst; \ } while(0) -#define save_committed_tkt(tk) \ - memcpy((tk)->last_valid_tk, tk, sizeof(struct ticket_config)) - #define is_term_invalid(tk, term) \ - (tk->last_valid_tk->current_term && \ - tk->last_valid_tk->current_term > term) + ((tk)->last_valid_tk && (tk)->last_valid_tk->current_term > (term)) +void save_committed_tkt(struct ticket_config *tk); void disown_ticket(struct ticket_config *tk); int disown_if_expired(struct ticket_config *tk); int check_ticket(char *ticket, struct ticket_config **tc); int check_site(char *site, int *local); int grant_ticket(struct ticket_config *ticket); int revoke_ticket(struct ticket_config *ticket); int list_ticket(char **pdata, unsigned int *len); int ticket_recv(void *buf, struct booth_site *source); void reset_ticket(struct ticket_config *tk); void update_ticket_state(struct ticket_config *tk, struct booth_site *sender); int setup_ticket(void); int check_max_len_valid(const char *s, int max); int do_grant_ticket(struct ticket_config *ticket, int options); int do_revoke_ticket(struct ticket_config *tk); int find_ticket_by_name(const char *ticket, struct ticket_config **found); void set_ticket_wakeup(struct ticket_config *tk); int postpone_ticket_processing(struct ticket_config *tk); int acquire_ticket(struct ticket_config *tk, cmd_reason_t reason); int ticket_answer_list(int fd); int process_client_request(struct client *req_client, void *buf); int ticket_write(struct ticket_config *tk); void process_tickets(void); void tickets_log_info(void); char *state_to_string(uint32_t state_ho); int send_reject(struct booth_site *dest, struct ticket_config *tk, cmd_result_t code, struct boothc_ticket_msg *in_msg); int send_msg (int cmd, struct ticket_config *tk, struct booth_site *dest, struct boothc_ticket_msg *in_msg); int notify_client(struct ticket_config *tk, int client_fd, struct boothc_ticket_msg *msg); int ticket_broadcast(struct ticket_config *tk, cmd_request_t cmd, cmd_request_t expected_reply, cmd_result_t res, cmd_reason_t reason); int leader_update_ticket(struct ticket_config *tk); void add_random_delay(struct ticket_config *tk); void schedule_election(struct ticket_config *tk, cmd_reason_t reason); int check_attr_prereq(struct ticket_config *tk, grant_type_e grant_type); static inline void ticket_next_cron_at(struct ticket_config *tk, timetype *when) { copy_time(when, &tk->next_cron); } static inline void ticket_next_cron_in(struct ticket_config *tk, int interval) { timetype tv; set_future_time(&tv, interval); ticket_next_cron_at(tk, &tv); } static inline void ticket_activate_timeout(struct ticket_config *tk) { /* TODO: increase timeout when no answers */ tk_log_debug("activate ticket timeout in %d", tk->timeout); ticket_next_cron_in(tk, tk->timeout); } #endif /* _TICKET_H */