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Diffstat (limited to 'ntp_sources.c')
| -rw-r--r-- | ntp_sources.c | 1433 |
1 files changed, 1433 insertions, 0 deletions
diff --git a/ntp_sources.c b/ntp_sources.c new file mode 100644 index 0000000..d46c211 --- /dev/null +++ b/ntp_sources.c @@ -0,0 +1,1433 @@ +/* + chronyd/chronyc - Programs for keeping computer clocks accurate. + + ********************************************************************** + * Copyright (C) Richard P. Curnow 1997-2003 + * Copyright (C) Miroslav Lichvar 2011-2012, 2014, 2016, 2020-2021 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program 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 program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + ********************************************************************** + + ======================================================================= + + Functions which manage the pool of NTP sources that we are currently + a client of or peering with. + + */ + +#include "config.h" + +#include "sysincl.h" + +#include "array.h" +#include "ntp_sources.h" +#include "ntp_core.h" +#include "ntp_io.h" +#include "util.h" +#include "logging.h" +#include "local.h" +#include "memory.h" +#include "nameserv_async.h" +#include "privops.h" +#include "sched.h" + +/* ================================================== */ + +/* Maximum number of sources */ +#define MAX_SOURCES 65536 + +/* Record type private to this file, used to store information about + particular sources */ +typedef struct { + NTP_Remote_Address *remote_addr; /* The address of this source, non-NULL + means this slot in table is in use + (an IPADDR_ID address means the address + is not resolved yet) */ + NCR_Instance data; /* Data for the protocol engine for this source */ + char *name; /* Name of the source as it was specified + (may be an IP address) */ + int pool_id; /* ID of the pool from which was this source + added or INVALID_POOL */ + int tentative; /* Flag indicating there was no valid response + received from the source yet */ + uint32_t conf_id; /* Configuration ID, which can be shared with + different sources in case of a pool */ +} SourceRecord; + +/* Hash table of SourceRecord, its size is a power of two and it's never + more than half full */ +static ARR_Instance records; + +/* Number of sources in the hash table */ +static int n_sources; + +/* Flag indicating new sources will be started automatically when added */ +static int auto_start_sources = 0; + +/* Flag indicating a record is currently being modified */ +static int record_lock; + +/* Last assigned address ID */ +static uint32_t last_address_id = 0; + +/* Last assigned configuration ID */ +static uint32_t last_conf_id = 0; + +/* Source scheduled for name resolving (first resolving or replacement) */ +struct UnresolvedSource { + /* Current address of the source (IPADDR_ID is used for a single source + with unknown address and IPADDR_UNSPEC for a pool of sources) */ + NTP_Remote_Address address; + /* ID of the pool if not a single source */ + int pool_id; + /* Name to be resolved */ + char *name; + /* Flag indicating addresses should be used in a random order */ + int random_order; + /* Next unresolved source in the list */ + struct UnresolvedSource *next; +}; + +#define RESOLVE_INTERVAL_UNIT 7 +#define MIN_RESOLVE_INTERVAL 2 +#define MAX_RESOLVE_INTERVAL 9 +#define MIN_REPLACEMENT_INTERVAL 8 + +static struct UnresolvedSource *unresolved_sources = NULL; +static int resolving_interval = 0; +static int resolving_restart = 0; +static SCH_TimeoutID resolving_id; +static struct UnresolvedSource *resolving_source = NULL; +static NSR_SourceResolvingEndHandler resolving_end_handler = NULL; + +#define MAX_POOL_SOURCES 16 +#define INVALID_POOL (-1) + +/* Pool of sources with the same name */ +struct SourcePool { + /* Number of all sources from the pool */ + int sources; + /* Number of sources with unresolved address */ + int unresolved_sources; + /* Number of non-tentative sources */ + int confirmed_sources; + /* Maximum number of confirmed sources */ + int max_sources; +}; + +/* Array of SourcePool (indexed by their ID) */ +static ARR_Instance pools; + +/* Requested update of a source's address */ +struct AddressUpdate { + NTP_Remote_Address old_address; + NTP_Remote_Address new_address; +}; + +/* Update saved when record_lock is true */ +static struct AddressUpdate saved_address_update; + +/* ================================================== */ +/* Forward prototypes */ + +static void resolve_sources(void); +static void rehash_records(void); +static void handle_saved_address_update(void); +static void clean_source_record(SourceRecord *record); +static void remove_pool_sources(int pool_id, int tentative, int unresolved); +static void remove_unresolved_source(struct UnresolvedSource *us); + +static void +slew_sources(struct timespec *raw, + struct timespec *cooked, + double dfreq, + double doffset, + LCL_ChangeType change_type, + void *anything); + +/* ================================================== */ + +/* Flag indicating whether module is initialised */ +static int initialised = 0; + +/* ================================================== */ + +static SourceRecord * +get_record(unsigned index) +{ + return (SourceRecord *)ARR_GetElement(records, index); +} + +/* ================================================== */ + +static struct SourcePool * +get_pool(unsigned index) +{ + return (struct SourcePool *)ARR_GetElement(pools, index); +} + +/* ================================================== */ + +void +NSR_Initialise(void) +{ + n_sources = 0; + initialised = 1; + + records = ARR_CreateInstance(sizeof (SourceRecord)); + rehash_records(); + + pools = ARR_CreateInstance(sizeof (struct SourcePool)); + + LCL_AddParameterChangeHandler(slew_sources, NULL); +} + +/* ================================================== */ + +void +NSR_Finalise(void) +{ + NSR_RemoveAllSources(); + + LCL_RemoveParameterChangeHandler(slew_sources, NULL); + + ARR_DestroyInstance(records); + ARR_DestroyInstance(pools); + + while (unresolved_sources) + remove_unresolved_source(unresolved_sources); + + initialised = 0; +} + +/* ================================================== */ +/* Find a slot matching an IP address. It is assumed that there can + only ever be one record for a particular IP address. */ + +static int +find_slot(IPAddr *ip_addr, int *slot) +{ + SourceRecord *record; + uint32_t hash; + unsigned int i, size; + + size = ARR_GetSize(records); + + *slot = 0; + + switch (ip_addr->family) { + case IPADDR_INET4: + case IPADDR_INET6: + case IPADDR_ID: + break; + default: + return 0; + } + + hash = UTI_IPToHash(ip_addr); + + for (i = 0; i < size / 2; i++) { + /* Use quadratic probing */ + *slot = (hash + (i + i * i) / 2) % size; + record = get_record(*slot); + + if (!record->remote_addr) + break; + + if (UTI_CompareIPs(&record->remote_addr->ip_addr, ip_addr, NULL) == 0) + return 1; + } + + return 0; +} + +/* ================================================== */ +/* Find a slot matching an IP address and port. The function returns: + 0 => IP not matched, empty slot returned if a valid address was provided + 1 => Only IP matched, port doesn't match + 2 => Both IP and port matched. */ + +static int +find_slot2(NTP_Remote_Address *remote_addr, int *slot) +{ + if (!find_slot(&remote_addr->ip_addr, slot)) + return 0; + + return get_record(*slot)->remote_addr->port == remote_addr->port ? 2 : 1; +} + +/* ================================================== */ +/* Check if hash table of given size is sufficient to contain sources */ + +static int +check_hashtable_size(unsigned int sources, unsigned int size) +{ + return sources * 2 <= size; +} + +/* ================================================== */ + +static void +rehash_records(void) +{ + SourceRecord *temp_records; + unsigned int i, old_size, new_size; + int slot; + + assert(!record_lock); + + old_size = ARR_GetSize(records); + + temp_records = MallocArray(SourceRecord, old_size); + memcpy(temp_records, ARR_GetElements(records), old_size * sizeof (SourceRecord)); + + /* The size of the hash table is always a power of two */ + for (new_size = 1; !check_hashtable_size(n_sources, new_size); new_size *= 2) + ; + + ARR_SetSize(records, new_size); + + for (i = 0; i < new_size; i++) + get_record(i)->remote_addr = NULL; + + for (i = 0; i < old_size; i++) { + if (!temp_records[i].remote_addr) + continue; + + if (find_slot2(temp_records[i].remote_addr, &slot) != 0) + assert(0); + + *get_record(slot) = temp_records[i]; + } + + Free(temp_records); +} + +/* ================================================== */ + +/* Procedure to add a new source */ +static NSR_Status +add_source(NTP_Remote_Address *remote_addr, char *name, NTP_Source_Type type, + SourceParameters *params, int pool_id, uint32_t conf_id) +{ + SourceRecord *record; + int slot; + + assert(initialised); + + /* Find empty bin & check that we don't have the address already */ + if (find_slot2(remote_addr, &slot) != 0) { + return NSR_AlreadyInUse; + } else if (!name && !UTI_IsIPReal(&remote_addr->ip_addr)) { + /* Name is required for non-real addresses */ + return NSR_InvalidName; + } else if (n_sources >= MAX_SOURCES) { + return NSR_TooManySources; + } else { + if (remote_addr->ip_addr.family != IPADDR_INET4 && + remote_addr->ip_addr.family != IPADDR_INET6 && + remote_addr->ip_addr.family != IPADDR_ID) { + return NSR_InvalidAF; + } else { + n_sources++; + + if (!check_hashtable_size(n_sources, ARR_GetSize(records))) { + rehash_records(); + if (find_slot2(remote_addr, &slot) != 0) + assert(0); + } + + assert(!record_lock); + record_lock = 1; + + record = get_record(slot); + record->name = Strdup(name ? name : UTI_IPToString(&remote_addr->ip_addr)); + record->data = NCR_CreateInstance(remote_addr, type, params, record->name); + record->remote_addr = NCR_GetRemoteAddress(record->data); + record->pool_id = pool_id; + record->tentative = 1; + record->conf_id = conf_id; + + record_lock = 0; + + if (record->pool_id != INVALID_POOL) { + get_pool(record->pool_id)->sources++; + if (!UTI_IsIPReal(&remote_addr->ip_addr)) + get_pool(record->pool_id)->unresolved_sources++; + } + + if (auto_start_sources && UTI_IsIPReal(&remote_addr->ip_addr)) + NCR_StartInstance(record->data); + + /* The new instance is allowed to change its address immediately */ + handle_saved_address_update(); + + return NSR_Success; + } + } +} + +/* ================================================== */ + +static NSR_Status +change_source_address(NTP_Remote_Address *old_addr, NTP_Remote_Address *new_addr, + int replacement) +{ + int slot1, slot2, found; + SourceRecord *record; + LOG_Severity severity; + char *name; + + found = find_slot2(old_addr, &slot1); + if (found != 2) + return NSR_NoSuchSource; + + /* Make sure there is no other source using the new address (with the same + or different port), but allow a source to have its port changed */ + found = find_slot2(new_addr, &slot2); + if (found == 2 || (found != 0 && slot1 != slot2)) + return NSR_AlreadyInUse; + + assert(!record_lock); + record_lock = 1; + + record = get_record(slot1); + NCR_ChangeRemoteAddress(record->data, new_addr, !replacement); + + if (record->remote_addr != NCR_GetRemoteAddress(record->data) || + UTI_CompareIPs(&record->remote_addr->ip_addr, &new_addr->ip_addr, NULL) != 0) + assert(0); + + if (!UTI_IsIPReal(&old_addr->ip_addr) && UTI_IsIPReal(&new_addr->ip_addr)) { + if (auto_start_sources) + NCR_StartInstance(record->data); + if (record->pool_id != INVALID_POOL) + get_pool(record->pool_id)->unresolved_sources--; + } + + if (!record->tentative) { + record->tentative = 1; + + if (record->pool_id != INVALID_POOL) + get_pool(record->pool_id)->confirmed_sources--; + } + + record_lock = 0; + + name = record->name; + severity = UTI_IsIPReal(&old_addr->ip_addr) ? LOGS_INFO : LOGS_DEBUG; + + if (found == 0) { + /* The hash table must be rebuilt for the changed address */ + rehash_records(); + + LOG(severity, "Source %s %s %s (%s)", UTI_IPToString(&old_addr->ip_addr), + replacement ? "replaced with" : "changed to", + UTI_IPToString(&new_addr->ip_addr), name); + } else { + LOG(severity, "Source %s (%s) changed port to %d", + UTI_IPToString(&new_addr->ip_addr), name, new_addr->port); + } + + return NSR_Success; +} + +/* ================================================== */ + +static void +handle_saved_address_update(void) +{ + if (!UTI_IsIPReal(&saved_address_update.old_address.ip_addr)) + return; + + if (change_source_address(&saved_address_update.old_address, + &saved_address_update.new_address, 0) != NSR_Success) + /* This is expected to happen only if the old address is wrong */ + LOG(LOGS_ERR, "Could not change %s to %s", + UTI_IPSockAddrToString(&saved_address_update.old_address), + UTI_IPSockAddrToString(&saved_address_update.new_address)); + + saved_address_update.old_address.ip_addr.family = IPADDR_UNSPEC; +} + +/* ================================================== */ + +static int +replace_source_connectable(NTP_Remote_Address *old_addr, NTP_Remote_Address *new_addr) +{ + if (!NIO_IsServerConnectable(new_addr)) { + DEBUG_LOG("%s not connectable", UTI_IPToString(&new_addr->ip_addr)); + return 0; + } + + if (change_source_address(old_addr, new_addr, 1) == NSR_AlreadyInUse) + return 0; + + handle_saved_address_update(); + + return 1; +} + +/* ================================================== */ + +static void +process_resolved_name(struct UnresolvedSource *us, IPAddr *ip_addrs, int n_addrs) +{ + NTP_Remote_Address old_addr, new_addr; + SourceRecord *record; + unsigned short first = 0; + int i, j; + + if (us->random_order) + UTI_GetRandomBytes(&first, sizeof (first)); + + for (i = 0; i < n_addrs; i++) { + new_addr.ip_addr = ip_addrs[((unsigned int)i + first) % n_addrs]; + + DEBUG_LOG("(%d) %s", i + 1, UTI_IPToString(&new_addr.ip_addr)); + + if (us->pool_id != INVALID_POOL) { + /* In the pool resolving mode, try to replace a source from + the pool which does not have a real address yet */ + for (j = 0; j < ARR_GetSize(records); j++) { + record = get_record(j); + if (!record->remote_addr || record->pool_id != us->pool_id || + UTI_IsIPReal(&record->remote_addr->ip_addr)) + continue; + old_addr = *record->remote_addr; + new_addr.port = old_addr.port; + if (replace_source_connectable(&old_addr, &new_addr)) + ; + break; + } + } else { + new_addr.port = us->address.port; + if (replace_source_connectable(&us->address, &new_addr)) + break; + } + } +} + +/* ================================================== */ + +static int +is_resolved(struct UnresolvedSource *us) +{ + int slot; + + if (us->pool_id != INVALID_POOL) { + return get_pool(us->pool_id)->unresolved_sources <= 0; + } else { + /* If the address is no longer present, it was removed or replaced + (i.e. resolved) */ + return find_slot2(&us->address, &slot) == 0; + } +} + +/* ================================================== */ + +static void +resolve_sources_timeout(void *arg) +{ + resolving_id = 0; + resolve_sources(); +} + +/* ================================================== */ + +static void +name_resolve_handler(DNS_Status status, int n_addrs, IPAddr *ip_addrs, void *anything) +{ + struct UnresolvedSource *us, *next; + + us = (struct UnresolvedSource *)anything; + + assert(us == resolving_source); + assert(resolving_id == 0); + + DEBUG_LOG("%s resolved to %d addrs", us->name, n_addrs); + + switch (status) { + case DNS_TryAgain: + break; + case DNS_Success: + process_resolved_name(us, ip_addrs, n_addrs); + break; + case DNS_Failure: + LOG(LOGS_WARN, "Invalid host %s", us->name); + break; + default: + assert(0); + } + + next = us->next; + + /* Don't repeat the resolving if it (permanently) failed, it was a + replacement of a real address, or all addresses are already resolved */ + if (status == DNS_Failure || UTI_IsIPReal(&us->address.ip_addr) || is_resolved(us)) + remove_unresolved_source(us); + + /* If a restart was requested and this was the last source in the list, + start with the first source again (if there still is one) */ + if (!next && resolving_restart) { + next = unresolved_sources; + resolving_restart = 0; + } + + resolving_source = next; + + if (next) { + /* Continue with the next source in the list */ + DEBUG_LOG("resolving %s", next->name); + DNS_Name2IPAddressAsync(next->name, name_resolve_handler, next); + } else { + /* This was the last source in the list. If some sources couldn't + be resolved, try again in exponentially increasing interval. */ + if (unresolved_sources) { + resolving_interval = CLAMP(MIN_RESOLVE_INTERVAL, resolving_interval + 1, + MAX_RESOLVE_INTERVAL); + resolving_id = SCH_AddTimeoutByDelay(RESOLVE_INTERVAL_UNIT * (1 << resolving_interval), + resolve_sources_timeout, NULL); + } else { + resolving_interval = 0; + } + + /* This round of resolving is done */ + if (resolving_end_handler) + (resolving_end_handler)(); + } +} + +/* ================================================== */ + +static void +resolve_sources(void) +{ + struct UnresolvedSource *us, *next, *i; + + assert(!resolving_source); + + /* Remove sources that don't need to be resolved anymore */ + for (i = unresolved_sources; i; i = next) { + next = i->next; + if (is_resolved(i)) + remove_unresolved_source(i); + } + + if (!unresolved_sources) + return; + + PRV_ReloadDNS(); + + /* Start with the first source in the list, name_resolve_handler + will iterate over the rest */ + us = unresolved_sources; + + resolving_source = us; + DEBUG_LOG("resolving %s", us->name); + DNS_Name2IPAddressAsync(us->name, name_resolve_handler, us); +} + +/* ================================================== */ + +static void +append_unresolved_source(struct UnresolvedSource *us) +{ + struct UnresolvedSource **i; + + for (i = &unresolved_sources; *i; i = &(*i)->next) + ; + *i = us; + us->next = NULL; +} + +/* ================================================== */ + +static void +remove_unresolved_source(struct UnresolvedSource *us) +{ + struct UnresolvedSource **i; + + for (i = &unresolved_sources; *i; i = &(*i)->next) { + if (*i == us) { + *i = us->next; + Free(us->name); + Free(us); + break; + } + } +} + +/* ================================================== */ + +static int get_unused_pool_id(void) +{ + struct UnresolvedSource *us; + int i; + + for (i = 0; i < ARR_GetSize(pools); i++) { + if (get_pool(i)->sources > 0) + continue; + + /* Make sure there is no name waiting to be resolved using this pool */ + for (us = unresolved_sources; us; us = us->next) { + if (us->pool_id == i) + break; + } + if (us) + continue; + + return i; + } + + return INVALID_POOL; +} + +/* ================================================== */ + +static uint32_t +get_next_conf_id(uint32_t *conf_id) +{ + last_conf_id++; + + if (conf_id) + *conf_id = last_conf_id; + + return last_conf_id; +} + +/* ================================================== */ + +NSR_Status +NSR_AddSource(NTP_Remote_Address *remote_addr, NTP_Source_Type type, + SourceParameters *params, uint32_t *conf_id) +{ + return add_source(remote_addr, NULL, type, params, INVALID_POOL, + get_next_conf_id(conf_id)); +} + +/* ================================================== */ + +NSR_Status +NSR_AddSourceByName(char *name, int port, int pool, NTP_Source_Type type, + SourceParameters *params, uint32_t *conf_id) +{ + struct UnresolvedSource *us; + struct SourcePool *sp; + NTP_Remote_Address remote_addr; + int i, new_sources, pool_id; + uint32_t cid; + + /* If the name is an IP address, add the source with the address directly */ + if (UTI_StringToIP(name, &remote_addr.ip_addr)) { + remote_addr.port = port; + return add_source(&remote_addr, name, type, params, INVALID_POOL, + get_next_conf_id(conf_id)); + } + + /* Make sure the name is at least printable and has no spaces */ + for (i = 0; name[i] != '\0'; i++) { + if (!isgraph((unsigned char)name[i])) + return NSR_InvalidName; + } + + us = MallocNew(struct UnresolvedSource); + us->name = Strdup(name); + us->random_order = 0; + + remote_addr.ip_addr.family = IPADDR_ID; + remote_addr.ip_addr.addr.id = ++last_address_id; + remote_addr.port = port; + + if (!pool) { + us->pool_id = INVALID_POOL; + us->address = remote_addr; + new_sources = 1; + } else { + pool_id = get_unused_pool_id(); + if (pool_id != INVALID_POOL) { + sp = get_pool(pool_id); + } else { + sp = ARR_GetNewElement(pools); + pool_id = ARR_GetSize(pools) - 1; + } + + sp->sources = 0; + sp->unresolved_sources = 0; + sp->confirmed_sources = 0; + sp->max_sources = CLAMP(1, params->max_sources, MAX_POOL_SOURCES); + us->pool_id = pool_id; + us->address.ip_addr.family = IPADDR_UNSPEC; + new_sources = MIN(2 * sp->max_sources, MAX_POOL_SOURCES); + } + + append_unresolved_source(us); + + cid = get_next_conf_id(conf_id); + + for (i = 0; i < new_sources; i++) { + if (i > 0) + remote_addr.ip_addr.addr.id = ++last_address_id; + if (add_source(&remote_addr, name, type, params, us->pool_id, cid) != NSR_Success) + return NSR_TooManySources; + } + + return NSR_UnresolvedName; +} + +/* ================================================== */ + +void +NSR_SetSourceResolvingEndHandler(NSR_SourceResolvingEndHandler handler) +{ + resolving_end_handler = handler; +} + +/* ================================================== */ + +void +NSR_ResolveSources(void) +{ + /* Try to resolve unresolved sources now */ + if (unresolved_sources) { + /* Allow only one resolving to be running at a time */ + if (!resolving_source) { + if (resolving_id != 0) { + SCH_RemoveTimeout(resolving_id); + resolving_id = 0; + resolving_interval--; + } + resolve_sources(); + } else { + /* Try again as soon as the current resolving ends */ + resolving_restart = 1; + } + } else { + /* No unresolved sources, we are done */ + if (resolving_end_handler) + (resolving_end_handler)(); + } +} + +/* ================================================== */ + +void NSR_StartSources(void) +{ + NTP_Remote_Address *addr; + unsigned int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + addr = get_record(i)->remote_addr; + if (!addr || !UTI_IsIPReal(&addr->ip_addr)) + continue; + NCR_StartInstance(get_record(i)->data); + } +} + +/* ================================================== */ + +void NSR_AutoStartSources(void) +{ + auto_start_sources = 1; +} + +/* ================================================== */ + +static void +clean_source_record(SourceRecord *record) +{ + assert(record->remote_addr); + + if (record->pool_id != INVALID_POOL) { + struct SourcePool *pool = get_pool(record->pool_id); + + pool->sources--; + if (!UTI_IsIPReal(&record->remote_addr->ip_addr)) + pool->unresolved_sources--; + if (!record->tentative) + pool->confirmed_sources--; + if (pool->max_sources > pool->sources) + pool->max_sources = pool->sources; + } + + record->remote_addr = NULL; + NCR_DestroyInstance(record->data); + Free(record->name); + + n_sources--; +} + +/* ================================================== */ + +/* Procedure to remove a source. We don't bother whether the port + address is matched - we're only interested in removing a record for + the right IP address. */ +NSR_Status +NSR_RemoveSource(IPAddr *address) +{ + int slot; + + assert(initialised); + + if (find_slot(address, &slot) == 0) + return NSR_NoSuchSource; + + clean_source_record(get_record(slot)); + + /* Rehash the table to make sure there are no broken probe sequences. + This is costly, but it's not expected to happen frequently. */ + + rehash_records(); + + return NSR_Success; +} + +/* ================================================== */ + +void +NSR_RemoveSourcesById(uint32_t conf_id) +{ + SourceRecord *record; + unsigned int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (!record->remote_addr || record->conf_id != conf_id) + continue; + clean_source_record(record); + } + + rehash_records(); +} + +/* ================================================== */ + +void +NSR_RemoveAllSources(void) +{ + SourceRecord *record; + unsigned int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (!record->remote_addr) + continue; + clean_source_record(record); + } + + rehash_records(); +} + +/* ================================================== */ + +static void +resolve_source_replacement(SourceRecord *record) +{ + struct UnresolvedSource *us; + + DEBUG_LOG("trying to replace %s (%s)", + UTI_IPToString(&record->remote_addr->ip_addr), record->name); + + us = MallocNew(struct UnresolvedSource); + us->name = Strdup(record->name); + /* If there never was a valid reply from this source (e.g. it was a bad + replacement), ignore the order of addresses from the resolver to not get + stuck to a pair of addresses if the order doesn't change, or a group of + IPv4/IPv6 addresses if the resolver prefers inaccessible IP family */ + us->random_order = record->tentative; + us->pool_id = INVALID_POOL; + us->address = *record->remote_addr; + + append_unresolved_source(us); + NSR_ResolveSources(); +} + +/* ================================================== */ + +void +NSR_HandleBadSource(IPAddr *address) +{ + static struct timespec last_replacement; + struct timespec now; + SourceRecord *record; + IPAddr ip_addr; + double diff; + int slot; + + if (!find_slot(address, &slot)) + return; + + record = get_record(slot); + + /* Don't try to replace a source specified by an IP address unless the + address changed since the source was added (e.g. by NTS-KE) */ + if (UTI_StringToIP(record->name, &ip_addr) && + UTI_CompareIPs(&record->remote_addr->ip_addr, &ip_addr, NULL) == 0) + return; + + /* Don't resolve names too frequently */ + SCH_GetLastEventTime(NULL, NULL, &now); + diff = UTI_DiffTimespecsToDouble(&now, &last_replacement); + if (fabs(diff) < RESOLVE_INTERVAL_UNIT * (1 << MIN_REPLACEMENT_INTERVAL)) { + DEBUG_LOG("replacement postponed"); + return; + } + last_replacement = now; + + resolve_source_replacement(record); +} + +/* ================================================== */ + +void +NSR_RefreshAddresses(void) +{ + SourceRecord *record; + unsigned int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (!record->remote_addr) + continue; + + resolve_source_replacement(record); + } +} + +/* ================================================== */ + +NSR_Status +NSR_UpdateSourceNtpAddress(NTP_Remote_Address *old_addr, NTP_Remote_Address *new_addr) +{ + int slot; + + if (!UTI_IsIPReal(&old_addr->ip_addr) || !UTI_IsIPReal(&new_addr->ip_addr)) + return NSR_InvalidAF; + + if (UTI_CompareIPs(&old_addr->ip_addr, &new_addr->ip_addr, NULL) != 0 && + find_slot(&new_addr->ip_addr, &slot)) + return NSR_AlreadyInUse; + + /* If a record is being modified (e.g. by change_source_address(), or the + source is just being created), postpone the change to avoid corruption */ + + if (!record_lock) + return change_source_address(old_addr, new_addr, 0); + + if (UTI_IsIPReal(&saved_address_update.old_address.ip_addr)) + return NSR_TooManySources; + + saved_address_update.old_address = *old_addr; + saved_address_update.new_address = *new_addr; + + return NSR_Success; +} + +/* ================================================== */ + +static void remove_pool_sources(int pool_id, int tentative, int unresolved) +{ + SourceRecord *record; + unsigned int i, removed; + + for (i = removed = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + + if (!record->remote_addr || record->pool_id != pool_id) + continue; + + if ((tentative && !record->tentative) || + (unresolved && UTI_IsIPReal(&record->remote_addr->ip_addr))) + continue; + + DEBUG_LOG("removing %ssource %s", tentative ? "tentative " : "", + UTI_IPToString(&record->remote_addr->ip_addr)); + + clean_source_record(record); + removed++; + } + + if (removed) + rehash_records(); +} + +/* ================================================== */ + +uint32_t +NSR_GetLocalRefid(IPAddr *address) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + return NCR_GetLocalRefid(get_record(slot)->data); +} + +/* ================================================== */ + +char * +NSR_GetName(IPAddr *address) +{ + int slot; + + if (!find_slot(address, &slot)) + return NULL; + + return get_record(slot)->name; +} + +/* ================================================== */ + +/* This routine is called by ntp_io when a new packet arrives off the network, + possibly with an authentication tail */ +void +NSR_ProcessRx(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, + NTP_Local_Timestamp *rx_ts, NTP_Packet *message, int length) +{ + SourceRecord *record; + struct SourcePool *pool; + int slot; + + assert(initialised); + + /* Avoid unnecessary lookup if the packet cannot be a response from our + source. Otherwise, it must match both IP address and port number. */ + if (NTP_LVM_TO_MODE(message->lvm) != MODE_CLIENT && + find_slot2(remote_addr, &slot) == 2) { + record = get_record(slot); + + if (!NCR_ProcessRxKnown(record->data, local_addr, rx_ts, message, length)) + return; + + if (record->tentative) { + /* This was the first good reply from the source */ + record->tentative = 0; + + if (record->pool_id != INVALID_POOL) { + pool = get_pool(record->pool_id); + pool->confirmed_sources++; + + DEBUG_LOG("pool %s has %d confirmed sources", record->name, pool->confirmed_sources); + + /* If the number of sources from the pool reached the configured + maximum, remove the remaining tentative sources */ + if (pool->confirmed_sources >= pool->max_sources) + remove_pool_sources(record->pool_id, 1, 0); + } + } + } else { + NCR_ProcessRxUnknown(remote_addr, local_addr, rx_ts, message, length); + } +} + +/* ================================================== */ + +void +NSR_ProcessTx(NTP_Remote_Address *remote_addr, NTP_Local_Address *local_addr, + NTP_Local_Timestamp *tx_ts, NTP_Packet *message, int length) +{ + SourceRecord *record; + int slot; + + /* Avoid unnecessary lookup if the packet cannot be a request to our + source. Otherwise, it must match both IP address and port number. */ + if (NTP_LVM_TO_MODE(message->lvm) != MODE_SERVER && + find_slot2(remote_addr, &slot) == 2) { + record = get_record(slot); + NCR_ProcessTxKnown(record->data, local_addr, tx_ts, message, length); + } else { + NCR_ProcessTxUnknown(remote_addr, local_addr, tx_ts, message, length); + } +} + +/* ================================================== */ + +static void +slew_sources(struct timespec *raw, + struct timespec *cooked, + double dfreq, + double doffset, + LCL_ChangeType change_type, + void *anything) +{ + SourceRecord *record; + unsigned int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (record->remote_addr) { + if (change_type == LCL_ChangeUnknownStep) { + NCR_ResetInstance(record->data); + NCR_ResetPoll(record->data); + } else { + NCR_SlewTimes(record->data, cooked, dfreq, doffset); + } + } + } +} + +/* ================================================== */ + +int +NSR_SetConnectivity(IPAddr *mask, IPAddr *address, SRC_Connectivity connectivity) +{ + SourceRecord *record, *syncpeer; + unsigned int i, any; + + if (connectivity != SRC_OFFLINE) + NSR_ResolveSources(); + + any = 0; + syncpeer = NULL; + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (record->remote_addr) { + /* Ignore SRC_MAYBE_ONLINE connectivity change for unspecified unresolved + sources as they would always end up in the offline state */ + if ((address->family == IPADDR_UNSPEC && + (connectivity != SRC_MAYBE_ONLINE || UTI_IsIPReal(&record->remote_addr->ip_addr))) || + !UTI_CompareIPs(&record->remote_addr->ip_addr, address, mask)) { + any = 1; + if (NCR_IsSyncPeer(record->data)) { + syncpeer = record; + continue; + } + NCR_SetConnectivity(record->data, connectivity); + } + } + } + + /* Set the sync peer last to avoid unnecessary reference switching */ + if (syncpeer) + NCR_SetConnectivity(syncpeer->data, connectivity); + + return any; +} + +/* ================================================== */ + +int +NSR_ModifyMinpoll(IPAddr *address, int new_minpoll) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMinpoll(get_record(slot)->data, new_minpoll); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyMaxpoll(IPAddr *address, int new_maxpoll) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMaxpoll(get_record(slot)->data, new_maxpoll); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyMaxdelay(IPAddr *address, double new_max_delay) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMaxdelay(get_record(slot)->data, new_max_delay); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyMaxdelayratio(IPAddr *address, double new_max_delay_ratio) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMaxdelayratio(get_record(slot)->data, new_max_delay_ratio); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyMaxdelaydevratio(IPAddr *address, double new_max_delay_dev_ratio) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMaxdelaydevratio(get_record(slot)->data, new_max_delay_dev_ratio); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyMinstratum(IPAddr *address, int new_min_stratum) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyMinstratum(get_record(slot)->data, new_min_stratum); + return 1; +} + +/* ================================================== */ + +int +NSR_ModifyPolltarget(IPAddr *address, int new_poll_target) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_ModifyPolltarget(get_record(slot)->data, new_poll_target); + return 1; +} + +/* ================================================== */ + +int +NSR_InitiateSampleBurst(int n_good_samples, int n_total_samples, + IPAddr *mask, IPAddr *address) +{ + SourceRecord *record; + unsigned int i; + int any; + + any = 0; + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (record->remote_addr) { + if (address->family == IPADDR_UNSPEC || + !UTI_CompareIPs(&record->remote_addr->ip_addr, address, mask)) { + any = 1; + NCR_InitiateSampleBurst(record->data, n_good_samples, n_total_samples); + } + } + } + + return any; + +} + +/* ================================================== */ +/* The ip address is assumed to be completed on input, that is how we + identify the source record. */ + +void +NSR_ReportSource(RPT_SourceReport *report, struct timespec *now) +{ + int slot; + + if (find_slot(&report->ip_addr, &slot)) { + NCR_ReportSource(get_record(slot)->data, report, now); + } else { + report->poll = 0; + report->latest_meas_ago = 0; + } +} + +/* ================================================== */ + +int +NSR_GetAuthReport(IPAddr *address, RPT_AuthReport *report) +{ + int slot; + + if (!find_slot(address, &slot)) + return 0; + + NCR_GetAuthReport(get_record(slot)->data, report); + return 1; +} + +/* ================================================== */ +/* The ip address is assumed to be completed on input, that is how we + identify the source record. */ + +int +NSR_GetNTPReport(RPT_NTPReport *report) +{ + int slot; + + if (!find_slot(&report->remote_addr, &slot)) + return 0; + + NCR_GetNTPReport(get_record(slot)->data, report); + return 1; +} + +/* ================================================== */ + +void +NSR_GetActivityReport(RPT_ActivityReport *report) +{ + SourceRecord *record; + unsigned int i; + + report->online = 0; + report->offline = 0; + report->burst_online = 0; + report->burst_offline = 0; + report->unresolved = 0; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (!record->remote_addr) + continue; + + if (!UTI_IsIPReal(&record->remote_addr->ip_addr)) { + report->unresolved++; + } else { + NCR_IncrementActivityCounters(record->data, &report->online, &report->offline, + &report->burst_online, &report->burst_offline); + } + } +} + +/* ================================================== */ + +void +NSR_DumpAuthData(void) +{ + SourceRecord *record; + int i; + + for (i = 0; i < ARR_GetSize(records); i++) { + record = get_record(i); + if (!record->remote_addr) + continue; + NCR_DumpAuthData(record->data); + } +} |