lib: Provide RIB API to export internals via fuse

This adds a virtual RIB that is accessible as a filesystem that is
accessed through a fuse mountpoint (configurable , default is
/tmp/ouroboros). Currently, each IPCP will export its link state
database.

7 files changed, 565 insertions, 18 deletions

diff --git a/src/ipcpd/normal/main.c b/src/ipcpd/normal/main.c
index 2b35a04a..e6dd6717 100644
--- a/src/ipcpd/normal/main.c
+++ b/src/ipcpd/normal/main.c
@@ -26,21 +26,21 @@
 
 #define OUROBOROS_PREFIX "normal-ipcp"
 
-#include <ouroboros/endian.h>
-#include <ouroboros/logs.h>
+#include <ouroboros/errno.h>
+#include <ouroboros/hash.h>
 #include <ouroboros/ipcp-dev.h>
-#include <ouroboros/time_utils.h>
 #include <ouroboros/irm.h>
-#include <ouroboros/hash.h>
-#include <ouroboros/errno.h>
+#include <ouroboros/logs.h>
 #include <ouroboros/notifier.h>
+#include <ouroboros/rib.h>
+#include <ouroboros/time_utils.h>
 
 #include "addr_auth.h"
 #include "connmgr.h"
 #include "dir.h"
+#include "dt.h"
 #include "enroll.h"
 #include "fa.h"
-#include "dt.h"
 #include "ipcp.h"
 
 #include <stdbool.h>
@@ -338,6 +338,11 @@ int main(int    argc,
         }
 
         /* These components must be init at creation. */
+        if (rib_init("ipcpd-normal")) {
+                log_err("Failed to initialize RIB.");
+                goto fail_rib_init;
+        }
+
         if (connmgr_init()) {
                 log_err("Failed to initialize connection manager.");
                 goto fail_connmgr_init;
@@ -378,6 +383,8 @@ int main(int    argc,
 
         connmgr_fini();
 
+        rib_fini();
+
         irm_unbind_api(getpid(), ipcpi.name);
 
         ipcp_fini();
@@ -393,6 +400,8 @@ int main(int    argc,
  fail_enroll_init:
         connmgr_fini();
  fail_connmgr_init:
+        rib_fini();
+ fail_rib_init:
         irm_unbind_api(getpid(), ipcpi.name);
  fail_bind_api:
        ipcp_fini();
diff --git a/src/ipcpd/normal/pol/link_state.c b/src/ipcpd/normal/pol/link_state.c
index 7df09bce..3d9e8246 100644
--- a/src/ipcpd/normal/pol/link_state.c
+++ b/src/ipcpd/normal/pol/link_state.c
@@ -22,15 +22,18 @@
 
 #define _POSIX_C_SOURCE 200112L
 
+#include "config.h"
+
 #define OUROBOROS_PREFIX "link-state-routing"
 
+#include <ouroboros/dev.h>
 #include <ouroboros/errno.h>
+#include <ouroboros/fqueue.h>
 #include <ouroboros/list.h>
 #include <ouroboros/logs.h>
-#include <ouroboros/utils.h>
 #include <ouroboros/notifier.h>
-#include <ouroboros/dev.h>
-#include <ouroboros/fqueue.h>
+#include <ouroboros/rib.h>
+#include <ouroboros/utils.h>
 
 #include "ae.h"
 #include "connmgr.h"
@@ -52,6 +55,7 @@ typedef LinkStateMsg link_state_msg_t;
 #define LS_UPDATE_TIME 15
 #define LS_TIMEO       60
 #define LSA_MAX_LEN    128
+#define LSDB           "lsdb"
 
 #ifndef CLOCK_REALTIME_COARSE
 #define CLOCK_REALTIME_COARSE CLOCK_REALTIME
@@ -90,6 +94,7 @@ struct {
         fset_t *         mgmt_set;
 
         struct list_head db;
+        size_t           db_len;
 
         pthread_rwlock_t db_lock;
 
@@ -107,6 +112,106 @@ struct pol_routing_ops link_state_ops = {
         .routing_i_destroy = link_state_routing_i_destroy
 };
 
+static int str_adj(struct adjacency * adj,
+                   char *             buf,
+                   size_t             len)
+{
+        char        tmbuf[64];
+        struct tm * tm;
+
+        if (len < 256)
+                return -1;
+
+        tm = localtime(&adj->stamp);
+        strftime(tmbuf, sizeof(tmbuf), "%Y-%m-%d %H:%M:%S", tm);
+
+        sprintf(buf,
+                "src: %" PRIu64 "\n"
+                "dst: %" PRIu64 "\n"
+                "upd: %s\n",
+                adj->src,
+                adj->dst,
+                tmbuf);
+
+        return strlen(buf);
+}
+
+static int lsdb_read(const char * path,
+                     char *       buf,
+                     size_t       len)
+{
+        struct list_head * p;
+        char               entry[RIB_PATH_LEN + 1];
+
+        pthread_rwlock_rdlock(&ls.db_lock);
+
+        if (ls.db_len == 0) {
+                pthread_rwlock_unlock(&ls.db_lock);
+                return -EPERM;
+        }
+
+        list_for_each(p, &ls.db) {
+                struct adjacency * a = list_entry(p, struct adjacency, next);
+                sprintf(entry, "%" PRIu64 ".%" PRIu64, a->src, a->dst);
+                if (strcmp(entry, path) == 0) {
+                        len = str_adj(a, buf, len);
+                        pthread_rwlock_unlock(&ls.db_lock);
+                        return len;
+                }
+        }
+
+        pthread_rwlock_unlock(&ls.db_lock);
+
+        return -1;
+}
+
+static int lsdb_readdir(char *** buf)
+{
+        struct list_head * p;
+        char               entry[RIB_PATH_LEN + 1];
+        ssize_t            idx = 0;
+
+        pthread_rwlock_rdlock(&ls.db_lock);
+
+        if (ls.db_len == 0) {
+                pthread_rwlock_unlock(&ls.db_lock);
+                return 0;
+        }
+
+        *buf = malloc(sizeof(**buf) * ls.db_len);
+        if (*buf == NULL) {
+                pthread_rwlock_unlock(&ls.db_lock);
+                return -ENOMEM;
+        }
+
+        list_for_each(p, &ls.db) {
+                struct adjacency * a = list_entry(p, struct adjacency, next);
+                sprintf(entry, "%" PRIu64 ".%" PRIu64, a->src, a->dst);
+                (*buf)[idx] = malloc(strlen(entry) + 1);
+                if ((*buf)[idx] == NULL) {
+                        ssize_t j;
+                        for (j = 0; j < idx; ++j)
+                                free(*buf[j]);
+                        free(buf);
+                        pthread_rwlock_unlock(&ls.db_lock);
+                        return -ENOMEM;
+                }
+
+                strcpy((*buf)[idx], entry);
+
+                idx++;
+        }
+
+        pthread_rwlock_unlock(&ls.db_lock);
+
+        return idx;
+}
+
+static struct rib_ops r_ops = {
+        .read    = lsdb_read,
+        .readdir = lsdb_readdir
+};
+
 static int lsdb_add_nb(uint64_t     addr,
                        int          fd,
                        enum nb_type type)
@@ -214,11 +319,11 @@ static int lsdb_add_link(uint64_t    src,
 
         list_add_tail(&adj->next, p);
 
+        ls.db_len++;
+
         if (graph_update_edge(ls.graph, src, dst, *qs))
                 log_warn("Failed to add edge to graph.");
 
-        log_dbg("Added %" PRIu64 " - %" PRIu64" to lsdb.", adj->src, adj->dst);
-
         pthread_rwlock_unlock(&ls.db_lock);
 
         return 0;
@@ -239,8 +344,7 @@ static int lsdb_del_link(uint64_t src,
                         if (graph_del_edge(ls.graph, src, dst))
                                 log_warn("Failed to delete edge from graph.");
 
-                        log_dbg("Removed %" PRIu64 " - %" PRIu64" from lsdb.",
-                                a->src, a->dst);
+                        ls.db_len--;
 
                         pthread_rwlock_unlock(&ls.db_lock);
                         free(a);
@@ -587,6 +691,10 @@ int link_state_init(void)
         if (pthread_create(&ls.listener, NULL, ls_conn_handle, NULL))
                 goto fail_pthread_create_listener;
 
+        ls.db_len = 0;
+
+        rib_reg(LSDB, &r_ops);
+
         return 0;
 
  fail_pthread_create_listener:
@@ -614,6 +722,8 @@ void link_state_fini(void)
         struct list_head * p;
         struct list_head * h;
 
+        rib_unreg(LSDB);
+
         pthread_cancel(ls.listener);
         pthread_join(ls.listener, NULL);
 
diff --git a/src/irmd/config.h.in b/src/irmd/config.h.in
index c217fe93..d253a1ac 100644
--- a/src/irmd/config.h.in
+++ b/src/irmd/config.h.in
@@ -45,3 +45,8 @@
 
 #define IRMD_MIN_THREADS       @IRMD_MIN_THREADS@
 #define IRMD_ADD_THREADS       @IRMD_ADD_THREADS@
+
+#cmakedefine HAVE_FUSE
+#ifdef HAVE_FUSE
+#define FUSE_PREFIX "@FUSE_PREFIX@"
+#endif
diff --git a/src/irmd/main.c b/src/irmd/main.c
index c5caff6c..df903f40 100644
--- a/src/irmd/main.c
+++ b/src/irmd/main.c
@@ -1631,6 +1631,11 @@ static void irm_fini(void)
         pthread_cond_destroy(&irmd.cmd_cond);
         pthread_rwlock_destroy(&irmd.reg_lock);
         pthread_rwlock_destroy(&irmd.state_lock);
+
+#ifdef HAVE_FUSE
+        if (rmdir(FUSE_PREFIX))
+                log_dbg("Failed to remove " FUSE_PREFIX);
+#endif
 }
 
 void irmd_sig_handler(int         sig,
@@ -2249,7 +2254,12 @@ static int irm_init(void)
                 log_err("Failed to create rdrbuff.");
                 goto fail_rdrbuff;
         }
-
+#ifdef HAVE_FUSE
+        if (stat(FUSE_PREFIX, &st) != -1)
+                log_warn(FUSE_PREFIX " already exists...");
+        else
+                mkdir(FUSE_PREFIX, 0777);
+#endif
         irmd.csockfd = -1;
         irmd.state   = IRMD_RUNNING;
 
diff --git a/src/lib/CMakeLists.txt b/src/lib/CMakeLists.txt
index fd7ece83..26cecb44 100644
--- a/src/lib/CMakeLists.txt
+++ b/src/lib/CMakeLists.txt
@@ -37,10 +37,30 @@ if (HAVE_ROBUST_MUTEX)
     set(HAVE_ROBUST_MUTEX TRUE)
   else ()
     message(STATUS "Robust mutex support disabled by user")
-    set(HAVE_ROBUST_MUTEX FALSE)
   endif ()
 endif ()
 
+find_library(FUSE_LIBRARIES fuse QUIET)
+if (FUSE_LIBRARIES)
+  #FIXME: Check for version >= 2.6
+  set(DISABLE_FUSE FALSE CACHE BOOL "Disable FUSE support")
+  if (NOT DISABLE_FUSE)
+    message(STATUS "FUSE support enabled")
+    set(FUSE_PREFIX "/tmp/ouroboros" CACHE STRING
+    "Mountpoint for RIB filesystem")
+    set(HAVE_FUSE TRUE CACHE INTERNAL "")
+  else ()
+    message(STATUS "FUSE support disabled by user")
+  endif ()
+endif ()
+
+if (NOT HAVE_FUSE)
+  set(FUSE_LIBRARIES "")
+  set(FUSE_INCLUDE_DIR "")
+endif ()
+
+mark_as_advanced(FUSE_LIBRARIES)
+
 find_library(LIBGCRYPT_LIBRARIES gcrypt QUIET)
 if (LIBGCRYPT_LIBRARIES)
   find_path(LIBGCRYPT_INCLUDE_DIR gcrypt.h
@@ -163,6 +183,7 @@ set(SOURCE_FILES
   qos.c
   qoscube.c
   random.c
+  rib.c
   rq.c
   sha3.c
   shm_flow_set.c
@@ -188,7 +209,7 @@ endif (CMAKE_BUILD_TYPE MATCHES Debug)
 
 target_link_libraries(ouroboros ${LIBRT_LIBRARIES}
   ${LIBPTHREAD_LIBRARIES} ${PROTOBUF_C_LIBRARY} ${OPENSSL_LIBRARIES}
-  ${LIBGCRYPT_LIBRARIES})
+  ${LIBGCRYPT_LIBRARIES} ${FUSE_LIBRARIES})
 
 install(TARGETS ouroboros LIBRARY DESTINATION usr/lib)
 
diff --git a/src/lib/config.h.in b/src/lib/config.h.in
index e9c43389..a85ce7b4 100644
--- a/src/lib/config.h.in
+++ b/src/lib/config.h.in
@@ -45,6 +45,11 @@
 #cmakedefine HAVE_ROBUST_MUTEX
 #endif
 
+#cmakedefine HAVE_FUSE
+#ifdef HAVE_FUSE
+#define FUSE_PREFIX "@FUSE_PREFIX@"
+#endif
+
 #define PTHREAD_COND_CLOCK  @PTHREAD_COND_CLOCK@
 
 #define AP_MAX_FLOWS        @AP_MAX_FLOWS@
@@ -53,5 +58,3 @@
 
 #define DU_BUFF_HEADSPACE   @DU_BUFF_HEADSPACE@
 #define DU_BUFF_TAILSPACE   @DU_BUFF_TAILSPACE@
-
-#define CDAP_REPLY_TIMEOUT  @CDAP_REPLY_TIMEOUT@
diff --git a/src/lib/rib.c b/src/lib/rib.c
new file mode 100644
index 00000000..b6c8e140
--- /dev/null
+++ b/src/lib/rib.c
@@ -0,0 +1,389 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2017
+ *
+ * RIB export using FUSE
+ *
+ *    Dimitri Staessens <dimitri.staessens@ugent.be>
+ *    Sander Vrijders   <sander.vrijders@ugent.be>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * version 2.1 as published by the Free Software Foundation.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#define _POSIX_C_SOURCE 200112L
+
+#include "config.h"
+
+#include <ouroboros/errno.h>
+#include <ouroboros/list.h>
+#include <ouroboros/rib.h>
+#include <ouroboros/utils.h>
+
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef HAVE_FUSE
+#define _FILE_OFFSET_BITS 64
+#define FUSE_USE_VERSION  26
+#include <fuse.h>
+#endif
+
+#ifdef HAVE_FUSE
+
+#ifndef CLOCK_REALTIME_COARSE
+#define CLOCK_REALTIME_COARSE CLOCK_REALTIME
+#endif
+
+#define RT "/"
+
+struct reg_comp {
+        struct list_head next;
+
+        char             path[RIB_PATH_LEN + 1];
+        struct rib_ops * ops;
+};
+
+struct {
+        struct list_head   reg_comps;
+
+        char               mnt[RIB_PATH_LEN + 1];
+
+        struct fuse *      fuse;
+        struct fuse_chan * ch;
+
+        pthread_rwlock_t   lock;
+
+        pthread_t          fuse_thr;
+} rib;
+
+static int rib_open(const char *            path,
+                    struct fuse_file_info * info)
+{
+        (void) path;
+
+        info->nonseekable = 1;
+
+        return 0;
+}
+
+static int rib_opendir(const char *         path,
+                    struct fuse_file_info * info)
+{
+        (void) path;
+        (void) info;
+
+        return 0;
+}
+
+static int rib_read(const char *            path,
+                    char *                  buf,
+                    size_t                  size,
+                    off_t                   offset,
+                    struct fuse_file_info * info)
+{
+        struct list_head * p;
+        char               comp[RIB_PATH_LEN + 1];
+        char *             c;
+
+        strcpy(comp, path + 1);
+
+        c = strstr(comp, "/");
+
+        if (c != NULL)
+                *c = '\0';
+
+        (void) info;
+        (void) offset;
+
+        pthread_rwlock_wrlock(&rib.lock);
+
+        list_for_each(p, &rib.reg_comps) {
+                struct reg_comp * r = list_entry(p, struct reg_comp, next);
+                if (strcmp(comp, r->path) == 0) {
+                        int ret = r->ops->read(c + 1, buf, size);
+                        pthread_rwlock_unlock(&rib.lock);
+                        return ret;
+                }
+        }
+
+        pthread_rwlock_unlock(&rib.lock);
+
+        return -1;
+}
+
+static int rib_readdir(const char *            path,
+                       void *                  buf,
+                       fuse_fill_dir_t         filler,
+                       off_t                   offset,
+                       struct fuse_file_info * info)
+{
+        struct list_head * p;
+
+        (void) offset;
+        (void) info;
+
+        filler(buf, ".", NULL, 0);
+        filler(buf, "..", NULL, 0);
+
+        pthread_rwlock_rdlock(&rib.lock);
+
+        if (strcmp(path, RT) == 0) {
+                list_for_each(p, &rib.reg_comps) {
+                        struct reg_comp * c;
+                        c = list_entry(p, struct reg_comp, next);
+                        filler(buf, c->path, NULL, 0);
+                }
+        } else {
+                list_for_each(p, &rib.reg_comps) {
+                        char **           dir_entries;
+                        ssize_t           len;
+                        ssize_t           i;
+                        struct reg_comp * c;
+                        c = list_entry(p, struct reg_comp, next);
+                        if (strcmp(path + 1, c->path) == 0)
+                                if (c->ops->readdir == NULL)
+                                        break;
+
+                        len = c->ops->readdir(&dir_entries);
+                        if (len < 0)
+                                break;
+                        for (i = 0; i < len; ++i)
+                                filler(buf, dir_entries[i], NULL, 0);
+                        freepp(char, dir_entries, len);
+                }
+        }
+
+        pthread_rwlock_unlock(&rib.lock);
+
+        return 0;
+}
+
+static int rib_getattr(const char *  path,
+                       struct stat * st)
+{
+        struct list_head * p;
+        struct timespec    now;
+
+        clock_gettime(CLOCK_REALTIME_COARSE, &now);
+
+        memset(st, 0, sizeof(*st));
+
+        if (strcmp(path, RT) == 0) {
+                st->st_mode  = __S_IFDIR | 0755;
+                st->st_nlink = 2;
+                st->st_uid   = getuid();
+                st->st_gid   = getgid();
+                st->st_mtime = now.tv_sec;
+                return 0;
+        }
+
+        pthread_rwlock_rdlock(&rib.lock);
+
+        list_for_each(p, &rib.reg_comps) {
+                struct reg_comp * rc = list_entry(p, struct reg_comp, next);
+                if (strcmp(path + 1, rc->path) == 0) {
+                        st->st_mode  = __S_IFDIR | 0755;
+                        st->st_nlink = 2;
+                        break;
+                }
+        }
+
+        pthread_rwlock_unlock(&rib.lock);
+
+        if (st->st_mode == 0) {
+                char buf[4096];
+                st->st_nlink = 2;
+                st->st_mode = __S_IFREG | 0755;
+                st->st_size = rib_read(path, buf, 4096, 0, NULL);
+        }
+
+        st->st_uid   = getuid();
+        st->st_gid   = getgid();
+        st->st_mtime = now.tv_sec;
+
+        return 0;
+}
+
+static struct fuse_operations r_ops = {
+        .getattr = rib_getattr,
+        .open    = rib_open,
+        .opendir = rib_opendir,
+        .read    = rib_read,
+        .readdir = rib_readdir
+};
+
+static void * fuse_thr(void * o)
+{
+        (void) o;
+
+        if (fuse_loop(rib.fuse) < 0)
+                return (void *) -1;
+
+        return (void *) 0;
+}
+#endif /* HAVE_FUSE */
+
+int rib_init(const char * prefix)
+{
+#ifdef HAVE_FUSE
+        struct stat      st;
+        char *           argv[] = {"ignored",
+                                   NULL,
+                                   "-f",
+                                   "-o",
+                                   "ro,",
+                                   "allow_other,",
+                                   "default_permissions,",
+                                   "fsname=rib",
+                                   NULL};
+        struct fuse_args args   = FUSE_ARGS_INIT(0, NULL);
+
+        if (stat(FUSE_PREFIX, &st) == -1)
+                return -1;
+
+        sprintf(rib.mnt, FUSE_PREFIX "/%s.%d", prefix, getpid());
+
+        if (stat(rib.mnt, &st) == -1)
+                mkdir(rib.mnt, 0777);
+
+        argv[1] = rib.mnt;
+
+        fuse_opt_parse(&args, argv, NULL, NULL);
+
+        list_head_init(&rib.reg_comps);
+
+        rib.ch = fuse_mount(rib.mnt,  &args);
+        if (rib.ch == NULL)
+                goto fail_mount;
+
+        rib.fuse = fuse_new(rib.ch, &args, &r_ops, sizeof(r_ops), NULL);
+        if (rib.fuse == NULL)
+                goto fail_fuse;
+
+        if (pthread_rwlock_init(&rib.lock, NULL))
+                goto fail_rwlock_init;
+
+        if (pthread_create(&rib.fuse_thr, NULL, fuse_thr, NULL))
+                goto fail_fuse_thr;
+
+        fuse_opt_free_args(&args);
+
+        return 0;
+
+ fail_fuse_thr:
+        pthread_rwlock_destroy(&rib.lock);
+ fail_rwlock_init:
+        fuse_destroy(rib.fuse);
+ fail_fuse:
+        fuse_unmount(rib.mnt, rib.ch);
+ fail_mount:
+        fuse_opt_free_args(&args);
+        rmdir(rib.mnt);
+        return -1;
+#else
+        (void) prefix;
+        return 0;
+#endif
+}
+
+void rib_fini(void)
+{
+#ifdef HAVE_FUSE
+        struct list_head * p;
+        struct list_head * h;
+
+        fuse_unmount(rib.mnt, rib.ch);
+        pthread_join(rib.fuse_thr, NULL);
+
+        fuse_destroy(rib.fuse);
+
+        rmdir(rib.mnt);
+
+        pthread_rwlock_wrlock(&rib.lock);
+
+        list_for_each_safe(p, h, &rib.reg_comps) {
+                struct reg_comp * c = list_entry(p, struct reg_comp, next);
+                list_del(&c->next);
+                free(c);
+        }
+
+        pthread_rwlock_unlock(&rib.lock);
+
+        pthread_rwlock_destroy(&rib.lock);
+#endif
+}
+
+int rib_reg(const char *     path,
+            struct rib_ops * ops)
+{
+#ifdef HAVE_FUSE
+        struct reg_comp *  rc;
+        struct list_head * p;
+
+        pthread_rwlock_wrlock(&rib.lock);
+
+        list_for_each(p, &rib.reg_comps) {
+                struct reg_comp * r = list_entry(p, struct reg_comp, next);
+                if (strcmp(r->path, path) == 0) {
+                        pthread_rwlock_unlock(&rib.lock);
+                        return -EPERM;
+                }
+
+                if (strcmp(r->path, path) > 0)
+                        break;
+        }
+
+        rc = malloc(sizeof(*rc));
+        if (rc == NULL) {
+                pthread_rwlock_unlock(&rib.lock);
+                return -ENOMEM;
+        }
+
+        strcpy(rc->path, path);
+        rc->ops = ops;
+
+        list_add_tail(&rc->next, p);
+
+        pthread_rwlock_unlock(&rib.lock);
+#else
+        (void) path;
+        (void) ops;
+#endif
+        return 0;
+}
+
+void rib_unreg(const char * path)
+{
+#ifdef HAVE_FUSE
+        struct list_head * p;
+        struct list_head * h;
+
+        pthread_rwlock_wrlock(&rib.lock);
+
+        list_for_each_safe(p, h, &rib.reg_comps) {
+                struct reg_comp * r = list_entry(p, struct reg_comp, next);
+                if (strcmp(r->path, path) == 0) {
+                        list_del(&r->next);
+                        free(r);
+                        break;
+                }
+        }
+
+        pthread_rwlock_unlock(&rib.lock);
+#else
+        (void) path;
+#endif
+}