AUTOFS: a client library

This is the library the autofs client is using. automounter dlopen()s
the library so there is no header file, no pkgconfig file and the
library is in the libsss_autofs package, not in -devel.

The library provides the following interface:
* _sss_setautomntent() - select the map for processing
* _sss_getautomntent_r() - iterates through key/value pairs in the
                           selected map. The key is usually the mount
                           point, the value is mount information
                           (server:/export)
* _sss_getautomntbyname_r() - returns value for a specific key.
* _sss_endautomntent() deselect a map, clean up

3 files changed, 419 insertions, 0 deletions

diff --git a/src/sss_client/autofs/sss_autofs.c b/src/sss_client/autofs/sss_autofs.c
new file mode 100644
index 00000000..6195c0fc
--- /dev/null
+++ b/src/sss_client/autofs/sss_autofs.c
@@ -0,0 +1,360 @@
+/*
+    Authors:
+        Jakub Hrozek <jhrozek@redhat.com>
+
+    Copyright (C) 2012 Red Hat
+
+    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 3 of the License, 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.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include "sss_client/autofs/sss_autofs_private.h"
+#include "sss_client/sss_cli.h"
+
+/* Historically, autofs map and key names were just file names */
+#define MAX_AUTOMNTMAPNAME_LEN  NAME_MAX
+#define MAX_AUTOMNTKEYNAME_LEN  NAME_MAX
+
+struct automtent {
+    char *mapname;
+    size_t cursor;
+};
+
+errno_t
+_sss_setautomntent(const char *mapname, void **context)
+{
+    errno_t ret;
+    int errnop;
+    struct automtent *ctx;
+    char *name;
+    size_t name_len;
+    struct sss_cli_req_data rd;
+    uint8_t *repbuf = NULL;
+    size_t replen;
+
+    if (!mapname) return EINVAL;
+
+    sss_nss_lock();
+
+    ret = sss_strnlen(mapname, MAX_AUTOMNTMAPNAME_LEN, &name_len);
+    if (ret != 0) {
+        ret = EINVAL;
+        goto out;
+    }
+
+    name = malloc(sizeof(char)*name_len + 1);
+    if (name == NULL) {
+        ret = ENOMEM;
+        goto out;
+    }
+    strncpy(name, mapname, name_len + 1);
+
+    rd.data = name;
+    rd.len = name_len + 1;
+
+    sss_autofs_make_request(SSS_AUTOFS_SETAUTOMNTENT, &rd,
+                            &repbuf, &replen, &errnop);
+    if (errnop != 0) {
+        free(name);
+        ret = errnop;
+        goto out;
+    }
+
+    /* no results if not found */
+    if (((uint32_t *)repbuf)[0] == 0) {
+        free(name);
+        free(repbuf);
+        ret = ENOENT;
+        goto out;
+    }
+    free(repbuf);
+
+    ctx = malloc(sizeof(struct automtent));
+    if (!ctx) {
+        free(name);
+        ret = ENOMEM;
+        goto out;
+    }
+
+    ctx->mapname = strdup(name);
+    if (!ctx->mapname) {
+        free(name);
+        free(ctx);
+        ret = ENOMEM;
+        goto out;
+    }
+    ctx->cursor = 0;
+    free(name);
+
+    *context = ctx;
+    ret = 0;
+out:
+    sss_nss_unlock();
+    return ret;
+}
+
+errno_t
+_sss_getautomntent_r(char **key, char **value, void *context)
+{
+    int errnop;
+    errno_t ret;
+    size_t name_len;
+    struct sss_cli_req_data rd;
+    uint8_t *repbuf = NULL;
+    size_t replen;
+    struct automtent *ctx;
+    size_t ctr = 0;
+    size_t data_len = 0;
+    uint8_t *data;
+    uint32_t v;
+
+    char *buf;
+    uint32_t len;
+    uint32_t keylen;
+    uint32_t vallen;
+    size_t rp;
+
+    sss_nss_lock();
+
+    ctx = (struct automtent *) context;
+    if (!ctx) {
+        ret = EINVAL;
+        goto out;
+    }
+
+    /* Be paranoid in case someone tries to smuggle in a huge map name */
+    ret = sss_strnlen(ctx->mapname, MAX_AUTOMNTMAPNAME_LEN, &name_len);
+    if (ret != 0) {
+        ret = EINVAL;
+        goto out;
+    }
+
+    data_len = sizeof(uint32_t) +            /* mapname len */
+               name_len + 1 +                /* mapname\0   */
+               sizeof(uint32_t);             /* index into the map */
+
+    data = malloc(data_len);
+    if (!data) {
+        ret = ENOMEM;
+        goto out;
+    }
+
+    v = name_len;
+    SAFEALIGN_COPY_UINT32(data, &v, &ctr);
+
+    safealign_memcpy(data+ctr, ctx->mapname, name_len + 1, &ctr);
+
+    v = ctx->cursor;
+    SAFEALIGN_COPY_UINT32(data+ctr, &v, &ctr);
+
+    rd.data = data;
+    rd.len = data_len;
+
+    sss_autofs_make_request(SSS_AUTOFS_GETAUTOMNTENT, &rd,
+                            &repbuf, &replen, &errnop);
+    free(data);
+    if (errnop != 0) {
+        ret = errnop;
+        goto out;
+    }
+
+    /* Got reply, let's parse it */
+    rp = 0;
+    SAFEALIGN_COPY_UINT32(&len, repbuf+rp, &rp);
+    if (len == 0) {
+        /* End of iteration */
+        *key = NULL;
+        *value = NULL;
+        ret = ENOENT;
+        goto out;
+    }
+
+    SAFEALIGN_COPY_UINT32(&keylen, repbuf+rp, &rp);
+    if (keylen > len-rp) {
+        ret = EIO;
+        goto out;
+    }
+
+    buf = malloc(keylen);
+    if (!buf) {
+        ret = ENOMEM;
+        goto out;
+    }
+
+    safealign_memcpy(buf, repbuf+rp, keylen, &rp);
+    *key = buf;
+
+    SAFEALIGN_COPY_UINT32(&vallen, repbuf+rp, &rp);
+    if (vallen > len-rp) {
+        ret = EIO;
+        goto out;
+    }
+
+    buf = malloc(vallen);
+    if (!buf) {
+        free(*key);
+        ret = ENOMEM;
+        goto out;
+    }
+
+    safealign_memcpy(buf, repbuf+rp, vallen, &rp);
+    *value = buf;
+
+    /* Advance the cursor so that we'll fetch the next map
+     * next time getautomntent is called */
+    ctx->cursor++;
+    ret = 0;
+out:
+    free(repbuf);
+    sss_nss_unlock();
+    return ret;
+}
+
+errno_t
+_sss_getautomntbyname_r(const char *key, char **value, void *context)
+{
+    int errnop;
+    errno_t ret;
+    struct automtent *ctx;
+    size_t key_len;
+    size_t name_len;
+    size_t data_len = 0;
+    uint8_t *data;
+    uint32_t v;
+    size_t ctr = 0;
+    struct sss_cli_req_data rd;
+    uint8_t *repbuf = NULL;
+    size_t replen;
+
+    char *buf;
+    uint32_t len;
+    uint32_t vallen;
+    size_t rp;
+
+    sss_nss_lock();
+
+    ctx = (struct automtent *) context;
+    if (!ctx || !key) {
+        ret = EINVAL;
+        goto out;
+    }
+
+    /* Be paranoid in case someone tries to smuggle in a huge map name */
+    ret = sss_strnlen(ctx->mapname, MAX_AUTOMNTMAPNAME_LEN, &name_len);
+    if (ret != 0) {
+        ret = EINVAL;
+        goto out;
+    }
+
+    ret = sss_strnlen(ctx->mapname, MAX_AUTOMNTKEYNAME_LEN, &key_len);
+    if (ret != 0) {
+        ret = EINVAL;
+        goto out;
+    }
+
+
+    data_len = sizeof(uint32_t) +            /* mapname len */
+               name_len + 1 +                /* mapname\0   */
+               sizeof(uint32_t) +            /* keyname len */
+               key_len + 1;                  /* keyname\0   */
+
+    data = malloc(data_len);
+    if (!data) {
+        ret = ENOMEM;
+        goto out;
+    }
+
+    v = name_len;
+    SAFEALIGN_COPY_UINT32(data, &v, &ctr);
+
+    safealign_memcpy(data+ctr, ctx->mapname, name_len + 1, &ctr);
+
+    v = key_len;
+    SAFEALIGN_COPY_UINT32(data+ctr, &v, &ctr);
+
+    safealign_memcpy(data+ctr, key, key_len + 1, &ctr);
+
+    rd.data = data;
+    rd.len = data_len;
+
+    sss_autofs_make_request(SSS_AUTOFS_GETAUTOMNTBYNAME, &rd,
+                            &repbuf, &replen, &errnop);
+    free(data);
+    if (errnop != 0) {
+        ret = errnop;
+        goto out;
+    }
+
+    /* Got reply, let's parse it */
+    rp = 0;
+    SAFEALIGN_COPY_UINT32(&len, repbuf+rp, &rp);
+    if (len == 0) {
+        /* No data */
+        *value = NULL;
+        ret = ENOENT;
+        goto out;
+    }
+
+    SAFEALIGN_COPY_UINT32(&vallen, repbuf+rp, &rp);
+    if (vallen > len-rp) {
+        ret = EIO;
+        goto out;
+    }
+
+    buf = malloc(vallen);
+    if (!buf) {
+        ret = ENOMEM;
+        goto out;
+    }
+
+    safealign_memcpy(buf, repbuf+rp, vallen, &rp);
+    *value = buf;
+
+    ret = 0;
+out:
+    free(repbuf);
+    sss_nss_unlock();
+    return ret;
+}
+
+errno_t
+_sss_endautomntent(void **context)
+{
+    struct automtent *fctx;
+    errno_t ret;
+    int errnop;
+
+    if (!context) return 0;
+
+    sss_nss_lock();
+
+    fctx = (struct automtent *) *context;
+
+    free(fctx->mapname);
+    free(fctx);
+
+    sss_autofs_make_request(SSS_AUTOFS_ENDAUTOMNTENT,
+                            NULL, NULL, NULL, &errnop);
+    if (errnop != 0) {
+        ret = errnop;
+        goto out;
+    }
+
+    ret = 0;
+out:
+    sss_nss_unlock();
+    return ret;
+}
diff --git a/src/sss_client/autofs/sss_autofs.exports b/src/sss_client/autofs/sss_autofs.exports
new file mode 100644
index 00000000..f9ce8f5b
--- /dev/null
+++ b/src/sss_client/autofs/sss_autofs.exports
@@ -0,0 +1,14 @@
+EXPORTED {
+
+    # public functions
+    global:
+                _sss_setautomntent;
+                _sss_getautomntent_r;
+                _sss_getautomntbyname_r;
+                _sss_endautomntent;
+
+    # everything else is local
+    local:
+        *;
+};
+
diff --git a/src/sss_client/autofs/sss_autofs_private.h b/src/sss_client/autofs/sss_autofs_private.h
new file mode 100644
index 00000000..6459c1cc
--- /dev/null
+++ b/src/sss_client/autofs/sss_autofs_private.h
@@ -0,0 +1,45 @@
+/*
+    Authors:
+        Jakub Hrozek <jhrozek@redhat.com>
+
+    Copyright (C) 2012 Red Hat
+
+    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 3 of the License, 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.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <errno.h>
+#include "util/util.h"
+
+/**
+ * Selects a map for processing.
+ */
+errno_t _sss_setautomntent(const char *mapname, void **context);
+
+/**
+ * Iterates through key/value pairs in the selected map. The key is usually
+ * the mount point, the value is mount information (server:/export)
+ */
+errno_t _sss_getautomntent_r(char **key, char **value, void *context);
+
+/**
+ * Returns value for a specific key
+ */
+errno_t
+_sss_getautomntbyname_r(const char *key, char **value, void *context);
+
+/**
+ * Deselect a map, end the processing
+ */
+errno_t _sss_endautomntent(void **context);
+