nss: custom parser for loading .leases file

The .leases file is currently loaded using the virLease class,
which in turn uses the virJSON parsing code. This pulls in a
heap of libvirt code (logging, hash tables, etc) which we do
not wish to depend on.

This uses the yajl parser code directly, so the only dep is
yajl and plain libc functions.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

cfg.mk

@@ -1226,10 +1226,10 @@ exclude_file_name_regexp--sc_prohibit_asprintf = \
   ^(cfg\.mk|bootstrap.conf$$|examples/|src/util/virstring\.[ch]$$|tests/vircgroupmock\.c|tools/virt-login-shell\.c|tools/nss/libvirt_nss\.c$$)
 
 exclude_file_name_regexp--sc_prohibit_strdup = \
-  ^(docs/|examples/|src/util/virstring\.c|tests/vir(netserverclient|cgroup)mock.c|tests/commandhelper\.c|tools/nss/libvirt_nss_macs\.c$$)
+  ^(docs/|examples/|src/util/virstring\.c|tests/vir(netserverclient|cgroup)mock.c|tests/commandhelper\.c|tools/nss/libvirt_nss_(leases|macs)\.c$$)
 
 exclude_file_name_regexp--sc_prohibit_close = \
-  (\.p[yl]$$|\.spec\.in$$|^docs/|^(src/util/virfile\.c|src/libvirt-stream\.c|tests/(vir.+mock\.c|commandhelper\.c|qemusecuritymock\.c)|tools/nss/libvirt_nss_macs\.c)$$)
+  (\.p[yl]$$|\.spec\.in$$|^docs/|^(src/util/virfile\.c|src/libvirt-stream\.c|tests/(vir.+mock\.c|commandhelper\.c|qemusecuritymock\.c)|tools/nss/libvirt_nss_(leases|macs)\.c)$$)
 
 exclude_file_name_regexp--sc_prohibit_empty_lines_at_EOF = \
   (^tests/(virhostcpu|virpcitest)data/|docs/js/.*\.js|docs/fonts/.*\.woff|\.diff|tests/virconfdata/no-newline\.conf$$)
@@ -1259,7 +1259,7 @@ exclude_file_name_regexp--sc_prohibit_canonicalize_file_name = \
   ^(cfg\.mk|tests/virfilemock\.c)$$
 
 exclude_file_name_regexp--sc_prohibit_raw_allocation = \
-  ^(docs/hacking\.html\.in|src/util/viralloc\.[ch]|examples/.*|tests/(securityselinuxhelper|(vircgroup|nss)mock|commandhelper)\.c|tools/wireshark/src/packet-libvirt\.c|tools/nss/libvirt_nss(_macs)?\.c)$$
+  ^(docs/hacking\.html\.in|src/util/viralloc\.[ch]|examples/.*|tests/(securityselinuxhelper|(vircgroup|nss)mock|commandhelper)\.c|tools/wireshark/src/packet-libvirt\.c|tools/nss/libvirt_nss(_leases|_macs)?\.c)$$
 
 exclude_file_name_regexp--sc_prohibit_readlink = \
   ^src/(util/virutil|lxc/lxc_container)\.c$$

tools/Makefile.am

@@ -476,7 +476,10 @@ endif ! WITH_BSD_NSS
 
 LIBVIRT_NSS_SOURCES = \
 	nss/libvirt_nss.c \
-	nss/libvirt_nss.h
+	nss/libvirt_nss.h \
+	nss/libvirt_nss_leases.c \
+	nss/libvirt_nss_leases.h \
+	$(NULL)
 
 if WITH_NSS
 noinst_LTLIBRARIES += nss/libnss_libvirt_impl.la
@@ -485,6 +488,7 @@ nss_libnss_libvirt_impl_la_SOURCES = \
 
 nss_libnss_libvirt_impl_la_CFLAGS = \
 	-DLIBVIRT_NSS \
+	$(YAJL_CFLAGS) \
 	$(AM_CFLAGS) \
 	$(NULL)
 

tools/nss/libvirt_nss.c

@@ -36,12 +36,13 @@
 # include <nsswitch.h>
 #endif
 
-#include "virlease.h"
 #include "viralloc.h"
 #include "virtime.h"
 #include "virsocketaddr.h"
 #include "configmake.h"
 
+#include "libvirt_nss_leases.h"
+
 #if defined(LIBVIRT_NSS_GUEST)
 # include "libvirt_nss_macs.h"
 #endif /* !LIBVIRT_NSS_GUEST */
@@ -51,13 +52,6 @@
 #define LIBVIRT_ALIGN(x) (((x) + __SIZEOF_POINTER__ - 1) & ~(__SIZEOF_POINTER__ - 1))
 #define FAMILY_ADDRESS_SIZE(family) ((family) == AF_INET6 ? 16 : 4)
 
-typedef struct {
-    unsigned char addr[16];
-    int af;
-    long long expirytime;
-} leaseAddress;
-
-
 static int
 leaseAddressSorter(const void *a,
                    const void *b)
@@ -77,147 +71,6 @@ sortAddr(leaseAddress *tmpAddress,
 }
 
 
-static int
-appendAddr(const char *name ATTRIBUTE_UNUSED,
-           leaseAddress **tmpAddress,
-           size_t *ntmpAddress,
-           virJSONValuePtr lease,
-           int af)
-{
-    const char *ipAddr;
-    virSocketAddr sa;
-    int family;
-    long long expirytime;
-    size_t i;
-
-    if (!(ipAddr = virJSONValueObjectGetString(lease, "ip-address"))) {
-        ERROR("ip-address field missing for %s", name);
-        return -1;
-    }
-
-    DEBUG("IP address: %s", ipAddr);
-
-    if (virSocketAddrParse(&sa, ipAddr, AF_UNSPEC) < 0) {
-        ERROR("Unable to parse %s", ipAddr);
-        return -1;
-    }
-
-    family = VIR_SOCKET_ADDR_FAMILY(&sa);
-    if (af != AF_UNSPEC && af != family) {
-        DEBUG("Skipping address which family is %d, %d requested", family, af);
-        return 0;
-    }
-
-    if (virJSONValueObjectGetNumberLong(lease, "expiry-time", &expirytime) < 0) {
-        /* A lease cannot be present without expiry-time */
-        ERROR("expiry-time field missing for %s", name);
-        return -1;
-    }
-
-    for (i = 0; i < *ntmpAddress; i++) {
-        if (memcmp((*tmpAddress)[i].addr,
-                   (family == AF_INET ?
-                    (void *) &sa.data.inet4.sin_addr.s_addr :
-                    (void *) &sa.data.inet6.sin6_addr.s6_addr),
-                   FAMILY_ADDRESS_SIZE(family)) == 0) {
-            DEBUG("IP address already in the list");
-            return 0;
-        }
-    }
-
-    if (VIR_REALLOC_N_QUIET(*tmpAddress, *ntmpAddress + 1) < 0) {
-        ERROR("Out of memory");
-        return -1;
-    }
-
-    (*tmpAddress)[*ntmpAddress].expirytime = expirytime;
-    (*tmpAddress)[*ntmpAddress].af = family;
-    memcpy((*tmpAddress)[*ntmpAddress].addr,
-           (family == AF_INET ?
-            (void *) &sa.data.inet4.sin_addr.s_addr :
-            (void *) &sa.data.inet6.sin6_addr.s6_addr),
-           FAMILY_ADDRESS_SIZE(family));
-    (*ntmpAddress)++;
-    return 0;
-}
-
-
-static int
-findLeaseInJSON(leaseAddress **tmpAddress,
-                size_t *ntmpAddress,
-                virJSONValuePtr leases_array,
-                size_t nleases,
-                const char *name,
-                const char **macs,
-                size_t nmacs,
-                int af,
-                bool *found)
-{
-    size_t i;
-    size_t j;
-    long long expirytime;
-    time_t currtime;
-
-    if ((currtime = time(NULL)) == (time_t) - 1) {
-        ERROR("Failed to get current system time");
-        return -1;
-    }
-
-    for (i = 0; i < nleases; i++) {
-        virJSONValuePtr lease = virJSONValueArrayGet(leases_array, i);
-
-        if (!lease) {
-            /* This should never happen (TM) */
-            ERROR("Unable to get element %zu of %zu", i, nleases);
-            return -1;
-        }
-
-        if (macs) {
-            const char *macAddr;
-            bool match = false;
-
-            macAddr = virJSONValueObjectGetString(lease, "mac-address");
-            if (!macAddr)
-                continue;
-
-            for (j = 0; j < nmacs && !match; j++) {
-                if (STREQ(macs[j], macAddr))
-                    match = true;
-            }
-            if (!match)
-                continue;
-        } else {
-            const char *lease_name;
-
-            lease_name = virJSONValueObjectGetString(lease, "hostname");
-
-            if (STRNEQ_NULLABLE(name, lease_name))
-                continue;
-        }
-
-        if (virJSONValueObjectGetNumberLong(lease, "expiry-time", &expirytime) < 0) {
-            /* A lease cannot be present without expiry-time */
-            ERROR("expiry-time field missing for %s", name);
-            return -1;
-        }
-
-        /* Do not report expired lease */
-        if (expirytime < (long long) currtime) {
-            DEBUG("Skipping expired lease for %s", name);
-            continue;
-        }
-
-        DEBUG("Found record for %s", name);
-        *found = true;
-
-        if (appendAddr(name, tmpAddress, ntmpAddress, lease, af) < 0)
-            return -1;
-    }
-
-    return 0;
-}
-
-
 /**
  * findLease:
  * @name: domain name to lookup
@@ -250,13 +103,12 @@ findLease(const char *name,
     int ret = -1;
     const char *leaseDir = LEASEDIR;
     struct dirent *entry;
-    VIR_AUTOPTR(virJSONValue) leases_array = NULL;
+    char **leaseFiles = NULL;
-    ssize_t nleases;
+    size_t nleaseFiles = 0;
-    VIR_AUTOFREE(leaseAddress *) tmpAddress = NULL;
-    size_t ntmpAddress = 0;
     char **macs = NULL;
     size_t nmacs = 0;
     size_t i;
+    time_t now;
 
     *address = NULL;
     *naddress = 0;
@@ -273,27 +125,21 @@ findLease(const char *name,
         goto cleanup;
     }
 
-    if (!(leases_array = virJSONValueNewArray())) {
-        ERROR("Failed to create json array");
-        goto cleanup;
-    }
-
     DEBUG("Dir: %s", leaseDir);
     while ((entry = readdir(dir)) != NULL) {
         char *path;
         size_t dlen = strlen(entry->d_name);
 
         if (dlen >= 7 && STREQ(entry->d_name + dlen - 7, ".status")) {
+            char **tmpLease;
             if (asprintf(&path, "%s/%s", leaseDir, entry->d_name) < 0)
                 goto cleanup;
 
-            DEBUG("Processing %s", path);
+            tmpLease = realloc(leaseFiles, sizeof(char *) * (nleaseFiles + 1));
-            if (virLeaseReadCustomLeaseFile(leases_array, path, NULL, NULL) < 0) {
+            if (!tmpLease)
-                ERROR("Unable to parse %s", path);
-                VIR_FREE(path);
                 goto cleanup;
-            }
+            leaseFiles = tmpLease;
-            VIR_FREE(path);
+            leaseFiles[nleaseFiles++] = path;
 #if defined(LIBVIRT_NSS_GUEST)
         } else if (dlen >= 5 && STREQ(entry->d_name + dlen - 5, ".macs")) {
             if (asprintf(&path, "%s/%s", leaseDir, entry->d_name) < 0)
@@ -313,9 +159,6 @@ findLease(const char *name,
     closedir(dir);
     dir = NULL;
 
-    nleases = virJSONValueArraySize(leases_array);
-    DEBUG("Read %zd leases", nleases);
-
 #if defined(LIBVIRT_NSS_GUEST)
     DEBUG("Finding with %zu macs", nmacs);
     if (!nmacs)
@@ -324,26 +167,38 @@ findLease(const char *name,
         DEBUG("  %s", macs[i]);
 #endif
 
-    if (findLeaseInJSON(&tmpAddress, &ntmpAddress,
+    if ((now = time(NULL)) == (time_t)-1) {
-                        leases_array, nleases,
+        DEBUG("Failed to get time");
-                        name, (const char**)macs, nmacs,
-                        af, found) < 0)
         goto cleanup;
+    }
 
-    DEBUG("Found %zu addresses", ntmpAddress);
+    for (i = 0; i < nleaseFiles; i++) {
-    sortAddr(tmpAddress, ntmpAddress);
+        if (findLeases(leaseFiles[i],
+                       name, macs, nmacs,
+                       af, now,
+                       address, naddress,
+                       found) < 0)
+            goto cleanup;
+    }
 
-    VIR_STEAL_PTR(*address, tmpAddress);
+    DEBUG("Found %zu addresses", *naddress);
-    *naddress = ntmpAddress;
+    sortAddr(*address, *naddress);
-    ntmpAddress = 0;
 
     ret = 0;
 
  cleanup:
     *errnop = errno;
+    for (i = 0; i < nleaseFiles; i++)
+        free(leaseFiles[i]);
+    free(leaseFiles);
     for (i = 0; i < nmacs; i++)
         free(macs[i]);
     free(macs);
+    if (ret < 0) {
+        free(*address);
+        *address = NULL;
+        *naddress = 0;
+    }
     if (dir)
         closedir(dir);
     return ret;

tools/nss/libvirt_nss_leases.c

@@ -0,0 +1,400 @@
+/*
+ * libvirt_nss_leases.c: Name Service Switch plugin lease file parser
+ *
+ * Copyright (C) 2019 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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 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, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+#include <yajl/yajl_gen.h>
+#include <yajl/yajl_parse.h>
+
+#include "libvirt_nss_leases.h"
+#include "libvirt_nss.h"
+#include "virsocketaddr.h"
+#include "viralloc.h"
+
+enum {
+    FIND_LEASES_STATE_START,
+    FIND_LEASES_STATE_LIST,
+    FIND_LEASES_STATE_ENTRY,
+};
+
+
+typedef struct {
+    const char *name;
+    char **macs;
+    size_t nmacs;
+    int state;
+    unsigned long long now;
+    int af;
+    bool *found;
+    leaseAddress **addrs;
+    size_t *naddrs;
+
+    char *key;
+    struct {
+        unsigned long long expiry;
+        char *ipaddr;
+        char *macaddr;
+        char *hostname;
+    } entry;
+} findLeasesParser;
+
+
+static int
+appendAddr(const char *name ATTRIBUTE_UNUSED,
+           leaseAddress **tmpAddress,
+           size_t *ntmpAddress,
+           const char *ipAddr,
+           long long expirytime,
+           int af)
+{
+    virSocketAddr sa;
+    int family;
+    size_t i;
+
+    DEBUG("IP address: %s", ipAddr);
+    if (virSocketAddrParse(&sa, ipAddr, AF_UNSPEC) < 0) {
+        ERROR("Unable to parse %s", ipAddr);
+        return -1;
+    }
+
+    family = VIR_SOCKET_ADDR_FAMILY(&sa);
+    if (af != AF_UNSPEC && af != family) {
+        DEBUG("Skipping address which family is %d, %d requested", family, af);
+        return 0;
+    }
+
+    for (i = 0; i < *ntmpAddress; i++) {
+        if (family == AF_INET) {
+            if (memcmp((*tmpAddress)[i].addr,
+                       &sa.data.inet4.sin_addr.s_addr,
+                       sizeof(sa.data.inet4.sin_addr.s_addr)) == 0) {
+                DEBUG("IP address already in the list");
+                return 0;
+            }
+        } else {
+            if (memcmp((*tmpAddress)[i].addr,
+                       &sa.data.inet6.sin6_addr.s6_addr,
+                       sizeof(sa.data.inet6.sin6_addr.s6_addr)) == 0) {
+                DEBUG("IP address already in the list");
+                return 0;
+            }
+        }
+    }
+
+    if (VIR_REALLOC_N_QUIET(*tmpAddress, *ntmpAddress + 1) < 0) {
+        ERROR("Out of memory");
+        return -1;
+    }
+
+    (*tmpAddress)[*ntmpAddress].expirytime = expirytime;
+    (*tmpAddress)[*ntmpAddress].af = family;
+    if (family == AF_INET)
+        memcpy((*tmpAddress)[*ntmpAddress].addr,
+               &sa.data.inet4.sin_addr.s_addr,
+               sizeof(sa.data.inet4.sin_addr.s_addr));
+    else
+        memcpy((*tmpAddress)[*ntmpAddress].addr,
+               &sa.data.inet6.sin6_addr.s6_addr,
+               sizeof(sa.data.inet6.sin6_addr.s6_addr));
+    (*ntmpAddress)++;
+    return 0;
+}
+
+
+static int
+findLeasesParserInteger(void *ctx,
+                        long long val)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse int state=%d '%lld' (map key '%s')",
+          parser->state, val, NULLSTR(parser->key));
+    if (!parser->key)
+        return 0;
+
+    if (parser->state == FIND_LEASES_STATE_ENTRY) {
+        if (STRNEQ(parser->key, "expiry-time"))
+            return 0;
+
+        parser->entry.expiry = val;
+    } else {
+        return 0;
+    }
+    return 1;
+}
+
+
+static int
+findLeasesParserString(void *ctx,
+                       const unsigned char *stringVal,
+                       size_t stringLen)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse string state=%d '%.*s' (map key '%s')",
+          parser->state, (int)stringLen, (const char *)stringVal,
+          NULLSTR(parser->key));
+    if (!parser->key)
+        return 0;
+
+    if (parser->state == FIND_LEASES_STATE_ENTRY) {
+        if (STREQ(parser->key, "ip-address")) {
+            if (!(parser->entry.ipaddr = strndup((char *)stringVal, stringLen)))
+                return 0;
+        } else if (STREQ(parser->key, "mac-address")) {
+            if (!(parser->entry.macaddr = strndup((char *)stringVal, stringLen)))
+                return 0;
+        } else if (STREQ(parser->key, "hostname")) {
+            if (!(parser->entry.hostname = strndup((char *)stringVal, stringLen)))
+                return 0;
+        } else {
+            return 0;
+        }
+    } else {
+        return 0;
+    }
+    return 1;
+}
+
+
+static int
+findLeasesParserMapKey(void *ctx,
+                       const unsigned char *stringVal,
+                       size_t stringLen)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse map key state=%d '%.*s'",
+          parser->state, (int)stringLen, (const char *)stringVal);
+
+    free(parser->key);
+    if (!(parser->key = strndup((char *)stringVal, stringLen)))
+        return 0;
+
+    return 1;
+}
+
+
+static int
+findLeasesParserStartMap(void *ctx)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse start map state=%d", parser->state);
+
+    if (parser->state != FIND_LEASES_STATE_LIST)
+        return 0;
+
+    free(parser->key);
+    parser->key = NULL;
+    parser->state = FIND_LEASES_STATE_ENTRY;
+
+    return 1;
+}
+
+
+static int
+findLeasesParserEndMap(void *ctx)
+{
+    findLeasesParser *parser = ctx;
+    size_t i;
+    bool found = false;
+
+    DEBUG("Parse end map state=%d", parser->state);
+
+    if (parser->entry.macaddr == NULL)
+        return 0;
+
+    if (parser->state != FIND_LEASES_STATE_ENTRY)
+        return 0;
+
+    if (parser->nmacs) {
+        DEBUG("Check %zu macs", parser->nmacs);
+        for (i = 0; i < parser->nmacs && !found; i++) {
+            DEBUG("Check mac '%s' vs '%s'", parser->macs[i], NULLSTR(parser->entry.macaddr));
+            if (STREQ_NULLABLE(parser->macs[i], parser->entry.macaddr))
+                found = true;
+        }
+    } else {
+        DEBUG("Check name '%s' vs '%s'", parser->name, NULLSTR(parser->entry.hostname));
+        if (STREQ_NULLABLE(parser->name, parser->entry.hostname))
+            found = true;
+    }
+    DEBUG("Found %d", found);
+    if (parser->entry.expiry < parser->now) {
+        DEBUG("Entry expired at %llu vs now %llu",
+              parser->entry.expiry, parser->now);
+        found = false;
+    }
+    if (!parser->entry.ipaddr)
+        found = false;
+
+    if (found) {
+        *parser->found = true;
+
+        if (appendAddr(parser->name,
+                       parser->addrs, parser->naddrs,
+                       parser->entry.ipaddr,
+                       parser->entry.expiry,
+                       parser->af) < 0)
+            return 0;
+    }
+
+    free(parser->entry.macaddr);
+    free(parser->entry.ipaddr);
+    free(parser->entry.hostname);
+    parser->entry.macaddr = NULL;
+    parser->entry.ipaddr = NULL;
+    parser->entry.hostname = NULL;
+
+    parser->state = FIND_LEASES_STATE_LIST;
+
+    return 1;
+}
+
+
+static int
+findLeasesParserStartArray(void *ctx)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse start array state=%d", parser->state);
+
+    if (parser->state == FIND_LEASES_STATE_START) {
+        parser->state = FIND_LEASES_STATE_LIST;
+    } else {
+        return 0;
+    }
+
+    return 1;
+}
+
+
+static int
+findLeasesParserEndArray(void *ctx)
+{
+    findLeasesParser *parser = ctx;
+
+    DEBUG("Parse end array state=%d", parser->state);
+
+    if (parser->state == FIND_LEASES_STATE_LIST)
+        parser->state = FIND_LEASES_STATE_START;
+    else
+        return 0;
+
+    return 1;
+}
+
+
+int
+findLeases(const char *file,
+           const char *name,
+           char **macs,
+           size_t nmacs,
+           int af,
+           time_t now,
+           leaseAddress **addrs,
+           size_t *naddrs,
+           bool *found)
+{
+    int fd = -1;
+    int ret = -1;
+    const yajl_callbacks parserCallbacks = {
+        NULL, /* null */
+        NULL, /* bool */
+        findLeasesParserInteger,
+        NULL, /* double */
+        NULL, /* number */
+        findLeasesParserString,
+        findLeasesParserStartMap,
+        findLeasesParserMapKey,
+        findLeasesParserEndMap,
+        findLeasesParserStartArray,
+        findLeasesParserEndArray,
+    };
+    findLeasesParser parserState = {
+        .name = name,
+        .macs = macs,
+        .nmacs = nmacs,
+        .af = af,
+        .now = now,
+        .found = found,
+        .addrs = addrs,
+        .naddrs = naddrs,
+    };
+    yajl_handle parser = NULL;
+    char line[1024];
+    int rv;
+
+    if ((fd = open(file, O_RDONLY)) < 0) {
+        ERROR("Cannot open %s", file);
+        goto cleanup;
+    }
+
+    parser = yajl_alloc(&parserCallbacks, NULL, &parserState);
+    if (!parser) {
+        ERROR("Unable to create JSON parser");
+        goto cleanup;
+    }
+
+    while (1) {
+        rv = read(fd, line, sizeof(line));
+        if (rv < 0)
+            goto cleanup;
+        if (rv == 0)
+            break;
+
+        if (yajl_parse(parser, (const unsigned char *)line, rv)  !=
+            yajl_status_ok) {
+            ERROR("Parse failed %s",
+                  yajl_get_error(parser, 1,
+                                 (const unsigned char*)line, rv));
+            goto cleanup;
+        }
+    }
+
+    if (yajl_complete_parse(parser) != yajl_status_ok) {
+        ERROR("Parse failed %s",
+              yajl_get_error(parser, 1, NULL, 0));
+        goto cleanup;
+    }
+
+    ret = 0;
+
+ cleanup:
+    if (ret != 0) {
+        free(*addrs);
+        *addrs = NULL;
+        *naddrs = 0;
+    }
+    yajl_free(parser);
+    free(parserState.entry.ipaddr);
+    free(parserState.entry.macaddr);
+    free(parserState.entry.hostname);
+    free(parserState.key);
+    if (fd != -1)
+        close(fd);
+    return ret;
+}

tools/nss/libvirt_nss_leases.h

@@ -0,0 +1,40 @@
+/*
+ * libvirt_nss_leases.h: Name Service Switch plugin lease file parser
+ *
+ * Copyright (C) 2019 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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 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, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "internal.h"
+
+typedef struct {
+    unsigned char addr[16];
+    int af;
+    long long expirytime;
+} leaseAddress;
+
+int
+findLeases(const char *file,
+           const char *name,
+           char **macs,
+           size_t nmacs,
+           int af,
+           time_t now,
+           leaseAddress **addrs,
+           size_t *naddrs,
+           bool *found);

tools/nss/libvirt_nss_macs.c

@@ -28,10 +28,8 @@
 #include <yajl/yajl_gen.h>
 #include <yajl/yajl_parse.h>
 
-#include "internal.h"
-
-#include "libvirt_nss.h"
 #include "libvirt_nss_macs.h"
+#include "libvirt_nss.h"
 
 enum {
     FIND_MACS_STATE_START,

tools/nss/libvirt_nss_macs.h

@@ -20,6 +20,8 @@
 
 #pragma once
 
+#include "internal.h"
+
 int
 findMACs(const char *file,
          const char *name,