Add initial nss responder skeleton

6 files changed, 494 insertions, 4 deletions

diff --git a/server/nss/nsssrv.c b/server/nss/nsssrv.c
new file mode 100644
index 00000000..c2826d27
--- /dev/null
+++ b/server/nss/nsssrv.c
@@ -0,0 +1,252 @@
+/*
+   SSSD
+
+   NSS Responder
+
+   Copyright (C) Simo Sorce <ssorce@redhat.com>	2008
+
+   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 <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <string.h>
+#include <sys/time.h>
+#include "../events/events.h"
+#include "../talloc/talloc.h"
+#include "util/util.h"
+#include "service.h"
+#include "nss/nsssrv.h"
+
+struct nss_ctx {
+    struct task_server *task;
+    struct fd_event *lfde;
+    int lfd;
+};
+
+struct cli_ctx {
+    int cfd;
+    struct fd_event *cfde;
+    struct sockaddr_un addr;
+    struct cli_request *creq;
+};
+
+static void set_nonblocking(int fd)
+{
+    unsigned v;
+    v = fcntl(fd, F_GETFL, 0);
+    fcntl(fd, F_SETFL, v | O_NONBLOCK);
+}
+
+static void set_close_on_exec(int fd)
+{
+    unsigned v;
+    v = fcntl(fd, F_GETFD, 0);
+    fcntl(fd, F_SETFD, v | FD_CLOEXEC);
+}
+
+static int client_destructor(struct cli_ctx *ctx)
+{
+    if (ctx->cfd > 0) close(ctx->cfd);
+    return 0;
+}
+
+static void client_send(struct event_context *ev, struct cli_ctx *ctx)
+{
+    int ret;
+
+    ret = nss_packet_send(ctx->creq->out, ctx->cfd);
+    if (ret == RES_RETRY) {
+        /* not all data was sent, loop again */
+        return;
+    }
+    if (ret != RES_SUCCESS) {
+        DEBUG(0, ("Failed to read request, aborting client!\n"));
+        talloc_free(ctx);
+        return;
+    }
+
+    /* ok all sent */
+    EVENT_FD_NOT_WRITEABLE(ctx->cfde);
+    EVENT_FD_READABLE(ctx->cfde);
+    talloc_free(ctx->creq);
+    ctx->creq = NULL;
+    return;
+}
+
+static void client_recv(struct event_context *ev, struct cli_ctx *ctx)
+{
+    int ret;
+
+    if (!ctx->creq) {
+        ctx->creq = talloc_zero(ctx, struct cli_request);
+        if (!ctx->creq) {
+            DEBUG(0, ("Failed to alloc request, aborting client!\n"));
+            talloc_free(ctx);
+            return;
+        }
+    }
+
+    if (!ctx->creq->in) {
+        ret = nss_packet_new(ctx->creq, 0, &ctx->creq->in);
+        if (ret != RES_SUCCESS) {
+            DEBUG(0, ("Failed to alloc request, aborting client!\n"));
+            talloc_free(ctx);
+            return;
+        }
+    }
+
+    ret = nss_packet_recv(ctx->creq->in, ctx->cfd);
+    switch (ret) {
+    case RES_SUCCESS:
+        /* do not read anymore */
+        EVENT_FD_NOT_READABLE(ctx->cfde);
+        /* execute command */
+    /*    nss_cmd_execute(ctx); */
+        break;
+
+    case RES_RETRY:
+        /* need to read still some data, loop again */
+        break;
+
+    default:
+        DEBUG(0, ("Failed to read request, aborting client!\n"));
+        talloc_free(ctx);
+    }
+
+    return;
+}
+
+static void client_fd_handler(struct event_context *ev,
+                              struct fd_event *fde,
+                              uint16_t flags, void *ptr)
+{
+    struct cli_ctx *ctx = talloc_get_type(ptr, struct cli_ctx);
+
+    if (flags & EVENT_FD_READ) {
+        client_recv(ev, ctx);
+        return;
+    }
+    if (flags & EVENT_FD_WRITE) {
+        client_send(ev, ctx);
+        return;
+    }
+}
+
+static void accept_fd_handler(struct event_context *ev,
+                              struct fd_event *fde,
+                              uint16_t flags, void *ptr)
+{
+    /* accept and attach new event handler */
+    struct nss_ctx *ctx = talloc_get_type(ptr, struct nss_ctx);
+    struct cli_ctx *cctx;
+    socklen_t len;
+
+    cctx = talloc_zero(ctx, struct cli_ctx);
+    if (!cctx) {
+        struct sockaddr_un addr;
+        int fd;
+        DEBUG(0, ("Out of memory trying to setup client context!\n"));
+        /* accept and close to signal the client we have a problem */
+        memset(&addr, 0, sizeof(addr));
+        len = sizeof(addr);
+        fd = accept(ctx->lfd, (struct sockaddr *)&addr, &len);
+        if (fd == -1) {
+            return;
+        }
+        close(fd);
+        return;
+    }
+
+    len = sizeof(cctx->addr);
+    cctx->cfd = accept(ctx->lfd, (struct sockaddr *)&cctx->addr, &len);
+    if (cctx->cfd == -1) {
+        DEBUG(1, ("Accept failed [%s]", strerror(errno)));
+        talloc_free(cctx);
+        return;
+    }
+
+    cctx->cfde = event_add_fd(ev, cctx, cctx->cfd,
+                              EVENT_FD_READ, client_fd_handler, cctx);
+    if (!cctx->cfde) {
+        close(cctx->cfd);
+        talloc_free(cctx);
+        DEBUG(1, ("Failed to queue client handler\n"));
+    }
+
+    talloc_set_destructor(cctx, client_destructor);
+
+    return;
+}
+
+/* create a unix socket and listen to it */
+static void set_unix_socket(struct event_context *ev,
+                            struct nss_ctx *ctx,
+                            const char *sock_name)
+{
+    struct sockaddr_un addr;
+
+    /* make sure we have no old sockets around */
+    unlink(sock_name);
+
+    ctx->lfd = socket(AF_UNIX, SOCK_STREAM, 0);
+    if (ctx->lfd == -1) {
+        return;
+    }
+
+    set_nonblocking(ctx->lfd);
+    set_close_on_exec(ctx->lfd);
+
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_family = AF_UNIX;
+    strncpy(addr.sun_path, sock_name, sizeof(addr.sun_path));
+
+    if (bind(ctx->lfd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+        DEBUG(0,("Unable to bind on socket '%s'\n", sock_name));
+        goto failed;
+    }
+    if (listen(ctx->lfd, 10) != 0) {
+        DEBUG(0,("Unable to listen on socket '%s'\n", sock_name));
+        goto failed;
+    }
+
+    ctx->lfde = event_add_fd(ev, ctx, ctx->lfd,
+                                 EVENT_FD_READ, accept_fd_handler, ctx);
+
+    return;
+
+failed:
+    close(ctx->lfd);
+}
+
+void nss_task_init(struct task_server *task)
+{
+    struct nss_ctx *ctx;
+
+    task_server_set_title(task, "sssd[nsssrv]");
+
+    ctx = talloc_zero(task, struct nss_ctx);
+    if (!ctx) {
+        task_server_terminate(task, "fatal error initializing nss_ctx\n");
+        return;
+    }
+    ctx->task = task;
+
+    set_unix_socket(task->event_ctx, ctx, SSS_NSS_SOCKET_NAME);
+
+}
diff --git a/server/nss/nsssrv.h b/server/nss/nsssrv.h
new file mode 100644
index 00000000..5e6c9aa5
--- /dev/null
+++ b/server/nss/nsssrv.h
@@ -0,0 +1,48 @@
+/*
+   SSSD
+
+   NSS Responder, header file
+
+   Copyright (C) Simo Sorce <ssorce@redhat.com>	2008
+
+   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/>.
+*/
+
+#ifndef __NSSSRV_H__
+#define __NSSSRV_H__
+
+#include <stdint.h>
+#include "../nss_client/sss_nss.h"
+
+struct nss_packet;
+
+struct cli_request {
+    enum sss_nss_command cmd;
+    void *cmd_req;
+
+    /* original request from the wire */
+    struct nss_packet *in;
+
+    /* reply data */
+    struct nss_packet *out;
+};
+
+/* from nsssrv_packet.c */
+int nss_packet_new(TALLOC_CTX *mem_ctx, size_t size,
+                      struct nss_packet **rpacket);
+int nss_packet_grow(struct nss_packet *packet, size_t size);
+int nss_packet_recv(struct nss_packet *packet, int fd);
+int nss_packet_send(struct nss_packet *packet, int fd);
+
+#endif /* __NSSSRV_H__ */
diff --git a/server/nss/nsssrv_packet.c b/server/nss/nsssrv_packet.c
new file mode 100644
index 00000000..e33568a3
--- /dev/null
+++ b/server/nss/nsssrv_packet.c
@@ -0,0 +1,185 @@
+/*
+   SSSD
+
+   NSS Responder, command parser
+
+   Copyright (C) Simo Sorce <ssorce@redhat.com>	2008
+
+   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 <sys/types.h>
+#include <sys/socket.h>
+#include <string.h>
+#include <errno.h>
+#include "../talloc/talloc.h"
+#include "util/util.h"
+#include "nss/nsssrv.h"
+
+#define NSSSRV_PACKET_MEM_SIZE 512
+
+struct nss_packet {
+    size_t memsize;
+    uint8_t *buffer;
+
+    /* header */
+    uint32_t *len;
+    uint32_t *cmd;
+    uint32_t *status;
+    uint32_t *reserved;
+
+    uint8_t *body;
+
+    /* io pointer */
+    size_t iop;
+};
+
+/*
+ * Allocate a new packet structure
+ *
+ * - if size is defined use it otherwise the default packet will be
+ *   NSSSRV_PACKET_MEM_SIZE bytes.
+ * - if buf is provided also give back the pointer to the base of
+ *   the buffer (the header), so that a packet can be written into
+ *   firecgtly from the wire
+ */
+int nss_packet_new(TALLOC_CTX *mem_ctx, size_t size,
+                   struct nss_packet **rpacket)
+{
+    struct nss_packet *packet;
+
+    packet = talloc(mem_ctx, struct nss_packet);
+    if (!packet) return RES_NOMEM;
+
+    if (size) {
+        int n = size % NSSSRV_PACKET_MEM_SIZE;
+        packet->memsize = (n + 1) * NSSSRV_PACKET_MEM_SIZE;
+    } else {
+        packet->memsize = NSSSRV_PACKET_MEM_SIZE;
+    }
+
+    packet->buffer = talloc_size(packet, packet->memsize);
+    if (!packet->buffer) {
+        talloc_free(packet);
+        return RES_NOMEM;
+    }
+    memset(packet->buffer, 0, SSS_NSS_HEADER_SIZE);
+
+    packet->len = &((uint32_t *)packet->buffer)[0];
+    packet->cmd = &((uint32_t *)packet->buffer)[1];
+    packet->status = &((uint32_t *)packet->buffer)[2];
+    packet->reserved = &((uint32_t *)packet->buffer)[3];
+    packet->body = (uint8_t *)&((uint32_t *)packet->buffer)[4];
+
+    *(packet->len) = size?size:SSS_NSS_HEADER_SIZE;
+
+    *rpacket = packet;
+
+    return RES_SUCCESS;
+}
+
+/* grows a packet size only in NSSSRV_PACKET_MEM_SIZE chunks */
+int nss_packet_grow(struct nss_packet *packet, size_t size)
+{
+    size_t totlen, len;
+    uint8_t *newmem;
+
+    if (size == 0) {
+        return RES_SUCCESS;
+    }
+
+    totlen = packet->memsize;
+    len = *packet->len + size;
+
+    /* make sure we do not overflow */
+    if (totlen < len) {
+        int n = len % NSSSRV_PACKET_MEM_SIZE + 1;
+        totlen += n * NSSSRV_PACKET_MEM_SIZE;
+        if (totlen < len) {
+            return RES_INVALID_DATA;
+        }
+    }
+
+    if (totlen > packet->memsize) {
+        newmem = talloc_realloc_size(packet, packet->buffer, totlen);
+        if (!newmem) {
+            return RES_NOMEM;
+        }
+
+        packet->memsize = totlen;
+        packet->buffer = newmem;
+        packet->len = &((uint32_t *)packet->buffer)[0];
+        packet->cmd = &((uint32_t *)packet->buffer)[1];
+        packet->status = &((uint32_t *)packet->buffer)[2];
+        packet->reserved = &((uint32_t *)packet->buffer)[3];
+        packet->body = (uint8_t *)&((uint32_t *)packet->buffer)[4];
+    }
+
+    *(packet->len) += size;
+
+    return 0;
+}
+
+int nss_packet_recv(struct nss_packet *packet, int fd)
+{
+    size_t rb;
+    size_t len;
+    void *buf;
+
+    buf = packet->buffer + packet->iop;
+    if (packet->iop > 4) len = *packet->len;
+    else len = packet->memsize;
+
+    errno = 0;
+    rb = recv(fd, buf, len, 0);
+
+    if (rb == -1 && errno == EAGAIN) {
+        return RES_RETRY;
+    }
+
+    packet->iop += rb;
+    if (packet->iop < 4) {
+        return RES_RETRY;
+    }
+
+    if (packet->iop < *packet->len) {
+        return RES_RETRY;
+    }
+
+    return RES_SUCCESS;
+}
+
+int nss_packet_send(struct nss_packet *packet, int fd)
+{
+    size_t rb;
+    size_t len;
+    void *buf;
+
+    buf = packet->buffer + packet->iop;
+    len = *packet->len - packet->iop;
+
+    errno = 0;
+    rb = send(fd, buf, len, 0);
+
+    if (rb == -1 && errno == EAGAIN) {
+        return RES_RETRY;
+    }
+
+    packet->iop += rb;
+    if (packet->iop < *packet->len) {
+        return RES_RETRY;
+    }
+
+    return RES_SUCCESS;
+}
diff --git a/server/server.c b/server/server.c
index a6958a0f..27fe09b7 100644
--- a/server/server.c
+++ b/server/server.c
@@ -32,7 +32,9 @@
 #include "../events/events.h"
 #include "../ldb/include/ldb.h"
 #include "service.h"
-#include "monitor.h"
+
+extern void monitor_task_init(struct task_server *task);
+extern void nss_task_init(struct task_server *task);
 
 static void sig_hup(int sig)
 {
@@ -198,9 +200,11 @@ int main(int argc, const char *argv[])
 
 	/* Services */
 	register_server_service("monitor", monitor_task_init);
+	register_server_service("nss", nss_task_init);
 
-	services = calloc(2, sizeof(char *));
+	services = calloc(3, sizeof(char *));
 	services[0] = "monitor";
+	services[1] = "nss";
 
 	status = server_service_startup(event_ctx, services);
 	if (status != RES_SUCCESS) {
diff --git a/server/server.mk b/server/server.mk
index 1a451ae7..f796ec69 100644
--- a/server/server.mk
+++ b/server/server.mk
@@ -1,6 +1,6 @@
-SERVER_OBJ = server.o monitor.o process.o service.o service_task.o util/signal.o util/become_daemon.o
+SERVER_OBJ = server.o monitor.o process.o service.o service_task.o util/signal.o util/become_daemon.o nss/nsssrv.o nss/nsssrv_packet.o
 
-install:: all 
+install:: all
 	${INSTALLCMD} -d $(DESTDIR)$(sbindir)
 	${INSTALLCMD} -m 755 sssd $(DESTDIR)$(sbindir)
 
diff --git a/server/util/util.h b/server/util/util.h
index 012fa1ff..495e3a24 100644
--- a/server/util/util.h
+++ b/server/util/util.h
@@ -22,6 +22,7 @@
 #define RES_ERROR 1
 #define RES_NOMEM 2
 #define RES_INVALID_DATA 3
+#define RES_RETRY 4
 
 #include "util/dlinklist.h"