setup basic jail packet structs/funcs

Signed-off-by: Toni Uhlig <matzeton@googlemail.com>

7 files changed, 130 insertions, 12 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index c2fe07c..6c23607 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,5 +1,5 @@
 sbin_PROGRAMS = potd
-potd_SOURCES = compat.c utils.c options.c log.c log_colored.c log_file.c socket.c pevent.c capabilities.c filesystem.c jail.c forward.c redirector.c protocol.c protocol_ssh.c main.c
+potd_SOURCES = compat.c utils.c options.c log.c log_colored.c log_file.c socket.c pevent.c capabilities.c filesystem.c jail_packet.c jail.c forward.c redirector.c protocol.c protocol_ssh.c main.c
 if HAVE_SECCOMP
 potd_SOURCES += pseccomp.c
 endif
diff --git a/src/jail.c b/src/jail.c
index 18b11c1..8d207a7 100644
--- a/src/jail.c
+++ b/src/jail.c
@@ -161,7 +161,7 @@ int jail_setup_event(jail_ctx *ctx[], size_t siz, event_ctx **ev_ctx)
         return 1;
 
     for (size_t i = 0; i < siz; ++i) {
-        if (event_add_sock(*ev_ctx, &ctx[i]->fwd_ctx.sock)) {
+        if (event_add_sock(*ev_ctx, &ctx[i]->fwd_ctx.sock, NULL)) {
             return 1;
         }
 
@@ -521,12 +521,12 @@ static int jail_socket_tty(prisoner_process *ctx, int tty_fd)
             ctx->host_buf, ctx->service_buf, ctx->client_psock.fd);
         goto finish;
     }
-    if (event_add_sock(ev_ctx, &ctx->client_psock)) {
+    if (event_add_sock(ev_ctx, &ctx->client_psock, NULL)) {
         E_STRERR("Jail event context for socket %s:%s",
             ctx->host_buf, ctx->service_buf);
         goto finish;
     }
-    if (event_add_fd(ev_ctx, tty_fd)) {
+    if (event_add_fd(ev_ctx, tty_fd, NULL)) {
         E_STRERR("Jail event context for tty fd %d",
             tty_fd);
         goto finish;
@@ -544,7 +544,7 @@ static int jail_socket_tty(prisoner_process *ctx, int tty_fd)
         E_STRERR("%s", "SIGNAL fd");
         goto finish;
     }
-    if (event_add_fd(ev_ctx, ev_cli.signal_fd)) {
+    if (event_add_fd(ev_ctx, ev_cli.signal_fd, NULL)) {
         E_STRERR("Jail SIGNAL fd %d", ev_cli.signal_fd);
         goto finish;
     }
diff --git a/src/jail_packet.c b/src/jail_packet.c
new file mode 100644
index 0000000..4e5bd64
--- /dev/null
+++ b/src/jail_packet.c
@@ -0,0 +1,57 @@
+#include <arpa/inet.h>
+
+#include "jail_packet.h"
+#include "utils.h"
+
+typedef struct jail_packet {
+    uint8_t type;
+    uint16_t size;
+} jail_packet;
+
+typedef ssize_t (*packet_callback)(jail_packet_ctx *ctx, unsigned char *data,
+                                   size_t siz);
+
+typedef struct jail_packet_callback {
+    uint8_t type;
+    packet_callback pc;
+} jail_packet_callback;
+
+static ssize_t pkt_header_read(unsigned char *buf, size_t siz);
+static ssize_t pkt_hello(jail_packet_ctx *ctx, unsigned char *data, size_t siz);
+
+#define PKT_CB(type, cb) \
+    { type, cb }
+static const jail_packet_callback jpc[] = {
+    PKT_CB(PKT_INVALID, NULL),
+    PKT_CB(PKT_HELLO, pkt_hello)
+};
+
+
+static ssize_t pkt_header_read(unsigned char *buf, size_t siz)
+{
+    jail_packet *pkt;
+
+    if (siz < sizeof(*pkt))
+        return -1;
+    pkt = (jail_packet *) buf;
+
+    if (pkt->type >= SIZEOF(jpc))
+        return -1;
+
+    pkt->size = ntohs(pkt->size);
+    if (siz < pkt->size)
+        return -1;
+
+    return pkt->size;
+}
+
+static ssize_t pkt_hello(jail_packet_ctx *ctx, unsigned char *data, size_t siz)
+{
+    return -1;
+}
+
+int jail_packet_loop(event_ctx *ctx, jail_packet_ctx *pkt_ctx,
+                     on_data_cb on_data)
+{
+    return 1;
+}
diff --git a/src/jail_packet.h b/src/jail_packet.h
new file mode 100644
index 0000000..0fc202d
--- /dev/null
+++ b/src/jail_packet.h
@@ -0,0 +1,56 @@
+/*
+ * jail_packet.h
+ * potd is licensed under the BSD license:
+ *
+ * Copyright (c) 2018 Toni Uhlig <matzeton@googlemail.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ *   this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ * - The names of its contributors may not be used to endorse or promote
+ *   products derived from this
+ *   software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef POTD_JAIL_PACKET_H
+#define POTD_JAIL_PACKET_H 1
+
+#include <stdint.h>
+
+#include "pevent.h"
+
+#define PKT_INVALID 0x0
+#define PKT_HELLO   0x1
+
+typedef enum jail_packet_state {
+    JP_NONE, JP_INVALID, JP_HELLO
+} jail_packet_state;
+
+typedef struct jail_packet_ctx {
+    jail_packet_state pstate;
+} jail_packet_ctx;
+
+
+int jail_packet_loop(event_ctx *ctx, jail_packet_ctx *pkt_ctx,
+                     on_data_cb on_data);
+
+#endif
diff --git a/src/pevent.c b/src/pevent.c
index 224c805..d0565f3 100644
--- a/src/pevent.c
+++ b/src/pevent.c
@@ -140,7 +140,7 @@ add_eventbuf(event_ctx *ctx)
     return &ctx->buffer_array[ctx->buffer_used - 1];
 }
 
-int event_add_sock(event_ctx *ctx, psocket *sock)
+int event_add_sock(event_ctx *ctx, psocket *sock, void *buf_user_data)
 {
     int s;
     struct epoll_event ev = {0,{0}};
@@ -150,6 +150,7 @@ int event_add_sock(event_ctx *ctx, psocket *sock)
 
     eb = add_eventbuf(ctx);
     eb->fd = sock->fd;
+    eb->buf_user_data = buf_user_data;
     assert(eb->buf_used == 0);
 
     ev.data.ptr = eb;
@@ -161,7 +162,7 @@ int event_add_sock(event_ctx *ctx, psocket *sock)
     return 0;
 }
 
-int event_add_fd(event_ctx *ctx, int fd)
+int event_add_fd(event_ctx *ctx, int fd, void *buf_user_data)
 {
     int s;
     struct epoll_event ev = {0,{0}};
@@ -171,6 +172,7 @@ int event_add_fd(event_ctx *ctx, int fd)
 
     eb = add_eventbuf(ctx);
     eb->fd = fd;
+    eb->buf_user_data = buf_user_data;
     assert(eb->buf_used == 0);
 
     ev.data.ptr = eb;
diff --git a/src/pevent.h b/src/pevent.h
index 0f387aa..1c50073 100644
--- a/src/pevent.h
+++ b/src/pevent.h
@@ -34,6 +34,7 @@
 #ifndef POTD_EVENT_H
 #define POTD_EVENT_H 1
 
+#include <stdio.h>
 #include <sys/epoll.h>
 
 #include "socket.h"
@@ -52,6 +53,8 @@ typedef struct event_buf {
 
     char buf[BUFSIZ];
     size_t buf_used;
+
+    void *buf_user_data;
 } event_buf;
 
 typedef struct event_ctx {
@@ -81,9 +84,9 @@ int event_setup(event_ctx *ctx);
 
 int event_validate_ctx(event_ctx *ctx);
 
-int event_add_sock(event_ctx *ctx, psocket *sock);
+int event_add_sock(event_ctx *ctx, psocket *sock, void *buf_user_data);
 
-int event_add_fd(event_ctx *ctx, int fd);
+int event_add_fd(event_ctx *ctx, int fd, void *buf_user_data);
 
 int event_loop(event_ctx *ctx, on_event_cb on_event, void *user_data);
 
diff --git a/src/redirector.c b/src/redirector.c
index e418224..da7bbd1 100644
--- a/src/redirector.c
+++ b/src/redirector.c
@@ -177,7 +177,7 @@ int redirector_setup_event(redirector_ctx *rdr_ctx[], size_t siz, event_ctx **ev
         return 1;
 
     for (size_t i = 0; i < siz; ++i) {
-        if (event_add_sock(*ev_ctx, &rdr_ctx[i]->sock)) {
+        if (event_add_sock(*ev_ctx, &rdr_ctx[i]->sock, NULL)) {
             return 1;
         }
 
@@ -412,7 +412,7 @@ client_mainloop(void *arg)
         args->rdr_ctx->fwd_ctx.host_buf,
         args->rdr_ctx->fwd_ctx.service_buf, fwd.fd);
 
-    if (event_add_sock(ev_ctx, &fwd)) {
+    if (event_add_sock(ev_ctx, &fwd, NULL)) {
         E_STRERR("Forward event context add to %s:%s forward fd %d",
             args->rdr_ctx->fwd_ctx.host_buf,
             args->rdr_ctx->fwd_ctx.service_buf, fwd.fd);
@@ -430,7 +430,7 @@ client_mainloop(void *arg)
             args->rdr_ctx->fwd_ctx.service_buf, fwd.fd);
         goto finish;
     }
-    if (event_add_sock(ev_ctx, &args->client_sock)) {
+    if (event_add_sock(ev_ctx, &args->client_sock, NULL)) {
         E_STRERR("Forward event context add to %s:%s forward fd %d",
 	        args->rdr_ctx->fwd_ctx.host_buf,
             args->rdr_ctx->fwd_ctx.service_buf, fwd.fd);