diff options
Diffstat (limited to '')
-rw-r--r-- | agents/virt/server/mcast.c | 622 |
1 files changed, 622 insertions, 0 deletions
diff --git a/agents/virt/server/mcast.c b/agents/virt/server/mcast.c new file mode 100644 index 0000000..a95ab37 --- /dev/null +++ b/agents/virt/server/mcast.c @@ -0,0 +1,622 @@ +/* + Copyright Red Hat, Inc. 2006 + + 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, or (at your option) any + later version. + + 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; see the file COPYING. If not, write to the + Free Software Foundation, Inc., 675 Mass Ave, Cambridge, + MA 02139, USA. +*/ +/* + * Author: Lon Hohberger <lhh at redhat.com> + */ + +#include "config.h" + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <signal.h> +#include <string.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/wait.h> +#include <sys/un.h> +#include <sys/socket.h> +#include <sys/select.h> +#include <sys/ioctl.h> +#include <arpa/inet.h> +#include <net/if.h> +#include <netinet/in.h> +#include <netdb.h> +#include <sys/time.h> +#include <fcntl.h> +#include <errno.h> +#include <pthread.h> +#include <nss.h> +#include <libgen.h> + +/* Local includes */ +#include "xvm.h" +#include "simple_auth.h" +#include "options.h" +#include "mcast.h" +#include "tcp.h" +#include "debug.h" +#include "fdops.h" +#include "list.h" +#include "simpleconfig.h" +#include "static_map.h" +#include "server_plugin.h" +#include "history.h" + +#define NAME "multicast" +#define MCAST_VERSION "1.3" + +#define MCAST_MAGIC 0xabb911a3 + +#define VALIDATE(info) \ +do {\ + if (!info || info->magic != MCAST_MAGIC)\ + return -EINVAL;\ +} while(0) + +typedef struct _mcast_options { + char *addr; + char *key_file; + int ifindex; + int family; + unsigned int port; + unsigned int hash; + unsigned int auth; + unsigned int flags; +} mcast_options; + + +typedef struct _mcast_info { + uint64_t magic; + void *priv; + map_object_t *map; + history_info_t *history; + char key[MAX_KEY_LEN]; + mcast_options args; + const fence_callbacks_t *cb; + ssize_t key_len; + int mc_sock; + int need_kill; +} mcast_info; + + +struct mcast_hostlist_arg { + map_object_t *map; + const char *src; + int fd; +}; + + +/* + * See if we fenced this node recently (successfully) + * If so, ignore the request for a few seconds. + * + * We purge our history when the entries time out. + */ +static int +check_history(void *a, void *b) { + fence_req_t *old = a, *current = b; + + if (old->request == current->request && + old->seqno == current->seqno && + !strcasecmp((const char *)old->domain, + (const char *)current->domain)) { + return 1; + } + return 0; +} + + +static int +connect_tcp(fence_req_t *req, fence_auth_type_t auth, + void *key, size_t key_len) +{ + int fd = -1; + struct sockaddr_in sin; + struct sockaddr_in6 sin6; + char buf[128]; + + switch(req->family) { + case PF_INET: + memset(&sin, 0, sizeof(sin)); + memcpy(&sin.sin_addr, req->address, + sizeof(sin.sin_addr)); + sin.sin_family = PF_INET; + fd = ipv4_connect(&sin.sin_addr, req->port, + 5); + if (fd < 0) { + printf("Failed to call back\n"); + return -1; + } + break; + case PF_INET6: + memset(&sin6, 0, sizeof(sin6)); + memcpy(&sin6.sin6_addr, req->address, + sizeof(sin6.sin6_addr)); + sin.sin_family = PF_INET6; + fd = ipv6_connect(&sin6.sin6_addr, req->port, + 5); + + memset(buf,0,sizeof(buf)); + inet_ntop(PF_INET6, &sin6.sin6_addr, buf, sizeof(buf)); + + if (fd < 0) { + printf("Failed to call back %s\n", buf); + return -1; + } + break; + default: + printf("Family = %d\n", req->family); + return -1; + } + + /* Noops if auth == AUTH_NONE */ + if (sock_response(fd, auth, key, key_len, 10) <= 0) { + printf("Failed to respond to challenge\n"); + close(fd); + return -1; + } + + if (sock_challenge(fd, auth, key, key_len, 10) <= 0) { + printf("Remote failed challenge\n"); + close(fd); + return -1; + } + return fd; +} + + +static int +mcast_hostlist(const char *vm_name, const char *vm_uuid, + int state, void *priv) +{ + struct mcast_hostlist_arg *arg = (struct mcast_hostlist_arg *)priv; + host_state_t hinfo; + struct timeval tv; + int ret; + + if (map_check2(arg->map, arg->src, vm_uuid, vm_name) == 0) { + /* if we don't have access to fence this VM, + * we should not see it in a hostlist either */ + return 0; + } + + strncpy((char *)hinfo.domain, vm_name, sizeof(hinfo.domain) - 1); + strncpy((char *)hinfo.uuid, vm_uuid, sizeof(hinfo.uuid) - 1); + hinfo.state = state; + + tv.tv_sec = 1; + tv.tv_usec = 0; + ret = _write_retry(arg->fd, &hinfo, sizeof(hinfo), &tv); + if (ret == sizeof(hinfo)) + return 0; + return 1; +} + + +static int +mcast_hostlist_begin(int fd) +{ + struct timeval tv; + char val = (char)RESP_HOSTLIST; + + tv.tv_sec = 1; + tv.tv_usec = 0; + return _write_retry(fd, &val, 1, &tv); +} + + +static int +mcast_hostlist_end(int fd) +{ + host_state_t hinfo; + struct timeval tv; + int ret; + + printf("Sending terminator packet\n"); + + memset(&hinfo, 0, sizeof(hinfo)); + + tv.tv_sec = 1; + tv.tv_usec = 0; + ret = _write_retry(fd, &hinfo, sizeof(hinfo), &tv); + if (ret == sizeof(hinfo)) + return 0; + return 1; +} + + +static int +do_fence_request_tcp(fence_req_t *req, mcast_info *info) +{ + char ip_addr_src[1024]; + int fd = -1; + char response = 1; + struct mcast_hostlist_arg arg; + + fd = connect_tcp(req, info->args.auth, info->key, info->key_len); + if (fd < 0) { + dbg_printf(2, "Could not send reply to fence request: %s\n", + strerror(errno)); + goto out; + } + + inet_ntop(req->family, req->address, + ip_addr_src, sizeof(ip_addr_src)); + + dbg_printf(2, "Request %d seqno %d src %s target %s\n", + req->request, req->seqno, ip_addr_src, req->domain); + + switch(req->request) { + case FENCE_NULL: + response = info->cb->null((char *)req->domain, info->priv); + break; + case FENCE_ON: + if (map_check(info->map, ip_addr_src, + (const char *)req->domain) == 0) { + response = RESP_PERM; + break; + } + response = info->cb->on((char *)req->domain, ip_addr_src, + req->seqno, info->priv); + break; + case FENCE_OFF: + if (map_check(info->map, ip_addr_src, + (const char *)req->domain) == 0) { + response = RESP_PERM; + break; + } + response = info->cb->off((char *)req->domain, ip_addr_src, + req->seqno, info->priv); + break; + case FENCE_REBOOT: + if (map_check(info->map, ip_addr_src, + (const char *)req->domain) == 0) { + response = RESP_PERM; + break; + } + response = info->cb->reboot((char *)req->domain, ip_addr_src, + req->seqno, info->priv); + break; + case FENCE_STATUS: + if (map_check(info->map, ip_addr_src, + (const char *)req->domain) == 0) { + response = RESP_PERM; + break; + } + response = info->cb->status((char *)req->domain, info->priv); + break; + case FENCE_DEVSTATUS: + response = info->cb->devstatus(info->priv); + break; + case FENCE_HOSTLIST: + arg.map = info->map; + arg.src = ip_addr_src; + arg.fd = fd; + + mcast_hostlist_begin(arg.fd); + response = info->cb->hostlist(mcast_hostlist, &arg, + info->priv); + mcast_hostlist_end(arg.fd); + break; + } + + dbg_printf(3, "Sending response to caller...\n"); + if (_write_retry(fd, &response, 1, NULL) < 0) { + perror("write"); + } + + /* XVM shotguns multicast packets, so we want to avoid + * acting on the same request multiple times if the first + * attempt was successful. + */ + history_record(info->history, req); +out: + if (fd != -1) + close(fd); + + return 1; +} + + +static int +mcast_dispatch(listener_context_t c, struct timeval *timeout) +{ + mcast_info *info; + fence_req_t data; + fd_set rfds; + struct sockaddr_in sin; + int len; + int n; + socklen_t slen; + + info = (mcast_info *)c; + VALIDATE(info); + + FD_ZERO(&rfds); + FD_SET(info->mc_sock, &rfds); + + n = select((info->mc_sock)+1, &rfds, NULL, NULL, timeout); + if (n <= 0) { + if (errno == EINTR || errno == EAGAIN) + n = 0; + else + dbg_printf(2, "select: %s\n", strerror(errno)); + return n; + } + + slen = sizeof(sin); + len = recvfrom(info->mc_sock, &data, sizeof(data), 0, + (struct sockaddr *)&sin, &slen); + + if (len <= 0) { + perror("recvfrom"); + return len; + } + + swab_fence_req_t(&data); + + if (!verify_request(&data, info->args.hash, info->key, + info->key_len)) { + printf("Key mismatch; dropping packet\n"); + return 0; + } + + printf("Request %d seqno %d domain %s\n", data.request, data.seqno, + data.domain); + + if (history_check(info->history, &data) == 1) { + printf("We just did this request; dropping packet\n"); + return 0; + } + + switch(info->args.auth) { + case AUTH_NONE: + case AUTH_SHA1: + case AUTH_SHA256: + case AUTH_SHA512: + printf("Plain TCP request\n"); + do_fence_request_tcp(&data, info); + break; + default: + printf("XXX Unhandled authentication\n"); + } + + return 0; +} + + +static int +mcast_config(config_object_t *config, mcast_options *args) +{ + char value[1024]; + int errors = 0; + + if (sc_get(config, "fence_virtd/@debug", value, sizeof(value))==0) + dset(atoi(value)); + + if (sc_get(config, "listeners/multicast/@key_file", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for key_file\n", value); + args->key_file = strdup(value); + } else { + args->key_file = strdup(DEFAULT_KEY_FILE); + if (!args->key_file) { + dbg_printf(1, "Failed to allocate memory\n"); + return -1; + } + } + + args->hash = DEFAULT_HASH; + if (sc_get(config, "listeners/multicast/@hash", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for hash\n", value); + if (!strcasecmp(value, "none")) { + args->hash = HASH_NONE; + } else if (!strcasecmp(value, "sha1")) { + args->hash = HASH_SHA1; + } else if (!strcasecmp(value, "sha256")) { + args->hash = HASH_SHA256; + } else if (!strcasecmp(value, "sha512")) { + args->hash = HASH_SHA512; + } else { + dbg_printf(1, "Unsupported hash: %s\n", value); + ++errors; + } + } + + args->auth = DEFAULT_AUTH; + if (sc_get(config, "listeners/multicast/@auth", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for auth\n", value); + if (!strcasecmp(value, "none")) { + args->auth = AUTH_NONE; + } else if (!strcasecmp(value, "sha1")) { + args->auth = AUTH_SHA1; + } else if (!strcasecmp(value, "sha256")) { + args->auth = AUTH_SHA256; + } else if (!strcasecmp(value, "sha512")) { + args->auth = AUTH_SHA512; + } else { + dbg_printf(1, "Unsupported auth: %s\n", value); + ++errors; + } + } + + args->family = PF_INET; + if (sc_get(config, "listeners/multicast/@family", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for family\n", value); + if (!strcasecmp(value, "ipv4")) { + args->family = PF_INET; + } else if (!strcasecmp(value, "ipv6")) { + args->family = PF_INET6; + } else { + dbg_printf(1, "Unsupported family: %s\n", value); + ++errors; + } + } + + if (sc_get(config, "listeners/multicast/@address", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for address\n", value); + args->addr = strdup(value); + } else { + if (args->family == PF_INET) { + args->addr = strdup(IPV4_MCAST_DEFAULT); + } else { + args->addr = strdup(IPV6_MCAST_DEFAULT); + } + } + if (!args->addr) { + return -1; + } + + args->port = DEFAULT_MCAST_PORT; + if (sc_get(config, "listeners/multicast/@port", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for port\n", value); + args->port = atoi(value); + if (args->port <= 0) { + dbg_printf(1, "Invalid port: %s\n", value); + ++errors; + } + } + + args->ifindex = 0; + if (sc_get(config, "listeners/multicast/@interface", + value, sizeof(value)-1) == 0) { + dbg_printf(1, "Got %s for interface\n", value); + args->ifindex = if_nametoindex(value); + if (args->ifindex < 0) { + dbg_printf(1, "Invalid interface: %s\n", value); + ++errors; + } + } + + return errors; +} + + +static int +mcast_init(listener_context_t *c, const fence_callbacks_t *cb, + config_object_t *config, map_object_t *map, void *priv) +{ + mcast_info *info; + int mc_sock, ret; + + /* Initialize NSS; required to do hashing, as silly as that + sounds... */ + if (NSS_NoDB_Init(NULL) != SECSuccess) { + printf("Could not initialize NSS\n"); + return 1; + } + + info = malloc(sizeof(*info)); + if (!info) + return -1; + memset(info, 0, sizeof(*info)); + + info->priv = priv; + info->cb = cb; + info->map = map; + + ret = mcast_config(config, &info->args); + if (ret < 0) { + perror("mcast_config"); + free(info); + return -1; + } else if (ret > 0) { + printf("%d errors found during configuration\n",ret); + free(info); + return -1; + } + + if (info->args.auth != AUTH_NONE || info->args.hash != HASH_NONE) { + info->key_len = read_key_file(info->args.key_file, + info->key, sizeof(info->key)); + if (info->key_len < 0) { + printf("Could not read %s; operating without " + "authentication\n", info->args.key_file); + info->args.auth = AUTH_NONE; + info->args.hash = HASH_NONE; + info->key_len = 0; + } + } + + if (info->args.family == PF_INET) + mc_sock = ipv4_recv_sk(info->args.addr, + info->args.port, + info->args.ifindex); + else + mc_sock = ipv6_recv_sk(info->args.addr, + info->args.port, + info->args.ifindex); + if (mc_sock < 0) { + printf("Could not set up multicast listen socket\n"); + free(info); + return -1; + } + + info->magic = MCAST_MAGIC; + info->mc_sock = mc_sock; + info->history = history_init(check_history, 10, sizeof(fence_req_t)); + *c = (listener_context_t)info; + return 0; +} + + +static int +mcast_shutdown(listener_context_t c) +{ + mcast_info *info = (mcast_info *)c; + + VALIDATE(info); + info->magic = 0; + history_wipe(info->history); + free(info->history); + free(info->args.key_file); + free(info->args.addr); + close(info->mc_sock); + free(info); + + return 0; +} + + +static listener_plugin_t mcast_plugin = { + .name = NAME, + .version = MCAST_VERSION, + .init = mcast_init, + .dispatch = mcast_dispatch, + .cleanup = mcast_shutdown, +}; + +double +LISTENER_VER_SYM(void) +{ + return PLUGIN_VERSION_LISTENER; +} + +const listener_plugin_t * +LISTENER_INFO_SYM(void) +{ + return &mcast_plugin; +} |