/* * Copyright (C) 2012 Stefan Walter * Copyright (C) 2013 Red Hat Inc. * * 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 contributors to this software 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. * * Author: Stef Walter */ #include "config.h" #include "argv.h" #include "compat.h" #define P11_DEBUG_FLAG P11_DEBUG_RPC #include "debug.h" #include "message.h" #include "pkcs11.h" #include "private.h" #include "rpc.h" #include "rpc-message.h" #include #include #include #include #include #include #include #ifdef OS_UNIX #include #include #include #include #include #endif #ifdef OS_WIN32 #include #endif #ifndef EPROTO #define EPROTO EIO #endif typedef struct { /* Never changes */ int fd; /* Protected by the lock */ p11_mutex_t write_lock; int refs; int last_code; bool sent_creds; /* This data is protected by read mutex */ p11_mutex_t read_lock; bool read_creds; uint32_t read_code; uint32_t read_olen; uint32_t read_dlen; } rpc_socket; static rpc_socket * rpc_socket_new (int fd) { rpc_socket *sock; sock = calloc (1, sizeof (rpc_socket)); return_val_if_fail (sock != NULL, NULL); sock->fd = fd; sock->last_code = 0x10; sock->read_creds = false; sock->sent_creds = false; sock->refs = 1; p11_mutex_init (&sock->write_lock); p11_mutex_init (&sock->read_lock); return sock; } #if 0 static rpc_socket * rpc_socket_ref (rpc_socket *sock) { assert (sock != NULL); p11_mutex_lock (&sock->write_lock); sock->refs++; p11_mutex_unlock (&sock->write_lock); return sock; } static bool rpc_socket_is_open (rpc_socket *sock) { assert (sock != NULL); return sock->fd >= 0; } #endif static void rpc_socket_close (rpc_socket *sock) { assert (sock != NULL); if (sock->fd != -1) close (sock->fd); sock->fd = -1; } static void rpc_socket_unref (rpc_socket *sock) { int release = 0; assert (sock != NULL); p11_mutex_lock (&sock->write_lock); if (--sock->refs == 0) release = 1; p11_mutex_unlock (&sock->write_lock); if (!release) return; assert (sock != NULL); assert (sock->refs == 0); rpc_socket_close (sock); p11_mutex_uninit (&sock->write_lock); p11_mutex_uninit (&sock->read_lock); } static bool write_all (int fd, unsigned char* data, size_t len) { int r; while (len > 0) { r = write (fd, data, len); if (r == -1) { if (errno == EPIPE) { p11_message ("couldn't send data: closed connection"); return false; } else if (errno != EAGAIN && errno != EINTR) { p11_message_err (errno, "couldn't send data"); return false; } } else { p11_debug ("wrote %d bytes", r); data += r; len -= r; } } return true; } static bool read_all (int fd, unsigned char* data, size_t len) { int r; while (len > 0) { r = read (fd, data, len); if (r == 0) { p11_message ("couldn't receive data: closed connection"); return false; } else if (r == -1) { if (errno != EAGAIN && errno != EINTR) { p11_message_err (errno, "couldn't receive data"); return false; } } else { p11_debug ("read %d bytes", r); data += r; len -= r; } } return true; } static CK_RV rpc_socket_write_inlock (rpc_socket *sock, int code, p11_buffer *options, p11_buffer *buffer) { unsigned char header[12]; unsigned char dummy = '\0'; /* The socket is locked and referenced at this point */ assert (buffer != NULL); /* Place holder byte, will later carry unix credentials (on some systems) */ if (!sock->sent_creds) { if (write_all (sock->fd, &dummy, 1) != 1) { p11_message_err (errno, "couldn't send socket credentials"); return CKR_DEVICE_ERROR; } sock->sent_creds = true; } p11_rpc_buffer_encode_uint32 (header, code); p11_rpc_buffer_encode_uint32 (header + 4, options->len); p11_rpc_buffer_encode_uint32 (header + 8, buffer->len); if (!write_all (sock->fd, header, 12) || !write_all (sock->fd, options->data, options->len) || !write_all (sock->fd, buffer->data, buffer->len)) return CKR_DEVICE_ERROR; return CKR_OK; } static p11_rpc_status write_at (int fd, unsigned char *data, size_t len, size_t offset, size_t *at) { p11_rpc_status status; ssize_t num; size_t from; int errn; assert (*at >= offset); if (*at >= offset + len) return P11_RPC_OK; from = *at - offset; assert (from < len); num = write (fd, data + from, len - from); errn = errno; /* Update state */ if (num > 0) *at += num; /* Completely written out this block */ if (num == len - from) { p11_debug ("ok: wrote block of %d", (int)num); status = P11_RPC_OK; /* Partially written out this block */ } else if (num >= 0) { p11_debug ("again: partial read of %d", (int)num); status = P11_RPC_AGAIN; /* Didn't write out block due to transient issue */ } else if (errn == EINTR || errn == EAGAIN || errn == EWOULDBLOCK) { p11_debug ("again: due to %d", errn); status = P11_RPC_AGAIN; /* Failure */ } else { p11_debug ("error: due to %d", errn); status = P11_RPC_ERROR; } errno = errn; return status; } p11_rpc_status p11_rpc_transport_write (int fd, size_t *state, int call_code, p11_buffer *options, p11_buffer *buffer) { unsigned char header[12] = { 0, }; p11_rpc_status status; assert (state != NULL); assert (options != NULL); assert (buffer != NULL); if (*state < 12) { p11_rpc_buffer_encode_uint32 (header, call_code); p11_rpc_buffer_encode_uint32 (header + 4, options->len); p11_rpc_buffer_encode_uint32 (header + 8, buffer->len); } status = write_at (fd, header, 12, 0, state); if (status == P11_RPC_OK) { status = write_at (fd, options->data, options->len, 12, state); } if (status == P11_RPC_OK) { status = write_at (fd, buffer->data, buffer->len, 12 + options->len, state); } /* All done */ if (status == P11_RPC_OK) *state = 0; return status; } static int rpc_socket_read (rpc_socket *sock, int *code, p11_buffer *buffer) { CK_RV ret = CKR_DEVICE_ERROR; unsigned char header[12]; unsigned char dummy; fd_set rfds; assert (code != NULL); assert (buffer != NULL); /* * We are not in the main socket lock here, but the socket * is referenced, and won't go away */ p11_mutex_lock (&sock->read_lock); if (!sock->read_creds) { if (read_all (sock->fd, &dummy, 1) != 1) return CKR_DEVICE_ERROR; sock->read_creds = true; } for (;;) { /* No message header has been read yet? ... read one in */ if (sock->read_code == 0) { if (!read_all (sock->fd, header, 12)) break; /* Decode and check the message header */ sock->read_code = p11_rpc_buffer_decode_uint32 (header); sock->read_olen = p11_rpc_buffer_decode_uint32 (header + 4); sock->read_dlen = p11_rpc_buffer_decode_uint32 (header + 8); if (sock->read_code == 0) { p11_message ("received invalid rpc header values: perhaps wrong protocol"); break; } } /* If it's our header (or caller doesn't care), then yay! */ if (*code == -1 || sock->read_code == *code) { /* We ignore the options, so read into the same as buffer */ if (!p11_buffer_reset (buffer, sock->read_olen) || !p11_buffer_reset (buffer, sock->read_dlen)) { warn_if_reached (); break; } /* Read in the the options first, and then data */ if (!read_all (sock->fd, buffer->data, sock->read_olen) || !read_all (sock->fd, buffer->data, sock->read_dlen)) break; buffer->len = sock->read_dlen; *code = sock->read_code; /* Yay, we got our data, off we go */ sock->read_code = 0; sock->read_olen = 0; sock->read_dlen = 0; ret = CKR_OK; break; } /* Give another thread the chance to read data for this header */ if (sock->read_code != 0) { p11_debug ("received header in wrong thread"); p11_mutex_unlock (&sock->read_lock); /* Used as a simple wait */ FD_ZERO (&rfds); FD_SET (sock->fd, &rfds); if (select (sock->fd + 1, &rfds, NULL, NULL, NULL) < 0) p11_message ("couldn't use select to wait on rpc socket"); p11_mutex_lock (&sock->read_lock); } } p11_mutex_unlock (&sock->read_lock); return ret; } static p11_rpc_status read_at (int fd, unsigned char *data, size_t len, size_t offset, size_t *at) { p11_rpc_status status; int errn; ssize_t num; size_t from; assert (*at >= offset); if (*at >= offset + len) return P11_RPC_OK; from = *at - offset; assert (from < len); num = read (fd, data + from, len - from); errn = errno; /* Update state */ if (num > 0) *at += num; /* Completely read out this block */ if (num == len - from) { p11_debug ("ok: read block of %d", (int)num); status = P11_RPC_OK; /* Partially read out this block */ } else if (num > 0) { p11_debug ("again: partial read of %d", (int)num); status = P11_RPC_AGAIN; /* End of file, valid if at offset zero */ } else if (num == 0) { if (offset == 0) { p11_debug ("eof: read zero bytes"); status = P11_RPC_EOF; } else { p11_debug ("error: early truncate"); errn = EPROTO; status = P11_RPC_ERROR; } /* Didn't read out block due to transient issue */ } else if (errn == EINTR || errn == EAGAIN || errn == EWOULDBLOCK) { p11_debug ("again: due to %d", errn); status = P11_RPC_AGAIN; /* Failure */ } else { p11_debug ("error: due to %d", errn); status = P11_RPC_ERROR; } errno = errn; return status; } p11_rpc_status p11_rpc_transport_read (int fd, size_t *state, int *call_code, p11_buffer *options, p11_buffer *buffer) { unsigned char *header; p11_rpc_status status; size_t len; assert (state != NULL); assert (call_code != NULL); assert (options != NULL); assert (buffer != NULL); /* Reading the header, we read it into @buffer */ if (*state < 12) { if (!p11_buffer_reset (buffer, 12)) return_val_if_reached (P11_RPC_ERROR); status = read_at (fd, buffer->data, 12, 0, state); if (status != P11_RPC_OK) return status; /* Parse out the header */ header = buffer->data; *call_code = p11_rpc_buffer_decode_uint32 (header); len = p11_rpc_buffer_decode_uint32 (header + 4); if (!p11_buffer_reset (options, len)) return_val_if_reached (P11_RPC_ERROR); options->len = len; len = p11_rpc_buffer_decode_uint32 (header + 8); if (!p11_buffer_reset (buffer, len)) return_val_if_reached (P11_RPC_ERROR); buffer->len = len; } /* At this point options has a valid len field */ status = read_at (fd, options->data, options->len, 12, state); if (status == P11_RPC_OK) { status = read_at (fd, buffer->data, buffer->len, 12 + options->len, state); } if (status == P11_RPC_OK) *state = 0; return status; } struct _p11_rpc_transport { p11_rpc_client_vtable vtable; p11_destroyer destroyer; rpc_socket *socket; p11_buffer options; }; static void rpc_transport_disconnect (p11_rpc_client_vtable *vtable, void *init_reserved) { p11_rpc_transport *rpc = (p11_rpc_transport *)vtable; if (rpc->socket) { rpc_socket_close (rpc->socket); rpc_socket_unref (rpc->socket); rpc->socket = NULL; } } static bool rpc_transport_init (p11_rpc_transport *rpc, const char *module_name, p11_destroyer destroyer) { rpc->destroyer = destroyer; p11_buffer_init_null (&rpc->options, 0); p11_buffer_add (&rpc->options, module_name, -1); return_val_if_fail (p11_buffer_ok (&rpc->options), false); return true; } static void rpc_transport_uninit (p11_rpc_transport *rpc) { p11_buffer_uninit (&rpc->options); } static CK_RV rpc_transport_buffer (p11_rpc_client_vtable *vtable, p11_buffer *request, p11_buffer *response) { p11_rpc_transport *rpc = (p11_rpc_transport *)vtable; CK_RV rv = CKR_OK; rpc_socket *sock; int call_code; assert (rpc != NULL); assert (request != NULL); assert (response != NULL); sock = rpc->socket; assert (sock != NULL); p11_mutex_lock (&sock->write_lock); assert (sock->refs > 0); sock->refs++; /* Get the next socket reply code */ call_code = sock->last_code++; if (sock->fd == -1) rv = CKR_DEVICE_ERROR; if (rv == CKR_OK) rv = rpc_socket_write_inlock (sock, call_code, &rpc->options, request); /* We unlock the socket mutex while reading a response */ if (rv == CKR_OK) { p11_mutex_unlock (&sock->write_lock); rv = rpc_socket_read (sock, &call_code, response); p11_mutex_lock (&sock->write_lock); } if (rv != CKR_OK && sock->fd != -1) { p11_message ("closing socket due to protocol failure"); close (sock->fd); sock->fd = -1; } sock->refs--; assert (sock->refs > 0); p11_mutex_unlock (&sock->write_lock); return rv; } #ifdef OS_UNIX typedef struct { p11_rpc_transport base; p11_array *argv; pid_t pid; } rpc_exec; static void rpc_exec_wait_or_terminate (pid_t pid) { bool terminated = false; int status; int sig; int ret; int i; for (i = 0; i < 3 * 1000; i += 100) { ret = waitpid (pid, &status, WNOHANG); if (ret != 0) break; p11_sleep_ms (100); } if (ret == 0) { p11_message ("process %d did not exit, terminating", (int)pid); kill (pid, SIGTERM); terminated = true; ret = waitpid (pid, &status, 0); } if (ret < 0) { p11_message_err (errno, "failed to wait for executed child: %d", (int)pid); status = 0; } else if (WIFEXITED (status)) { status = WEXITSTATUS (status); if (status == 0) p11_debug ("process %d exited with status 0", (int)pid); else p11_message ("process %d exited with status %d", (int)pid, status); } else if (WIFSIGNALED (status)) { sig = WTERMSIG (status); if (!terminated || sig != SIGTERM) p11_message ("process %d was terminated with signal %d", (int)pid, sig); } } static void rpc_exec_disconnect (p11_rpc_client_vtable *vtable, void *fini_reserved) { rpc_exec *rex = (rpc_exec *)vtable; if (rex->base.socket) rpc_socket_close (rex->base.socket); if (rex->pid) rpc_exec_wait_or_terminate (rex->pid); rex->pid = 0; /* Do the common disconnect stuff */ rpc_transport_disconnect (vtable, fini_reserved); } static int set_cloexec_on_fd (void *data, int fd) { int *max_fd = data; if (fd >= *max_fd) fcntl (fd, F_SETFD, FD_CLOEXEC); return 0; } static CK_RV rpc_exec_connect (p11_rpc_client_vtable *vtable, void *init_reserved) { rpc_exec *rex = (rpc_exec *)vtable; pid_t pid; int max_fd; int fds[2]; int errn; p11_debug ("executing rpc transport: %s", (char *)rex->argv->elem[0]); if (socketpair (AF_UNIX, SOCK_STREAM, 0, fds) < 0) { p11_message_err (errno, "failed to create pipe for remote"); return CKR_DEVICE_ERROR; } pid = fork (); switch (pid) { /* Failure */ case -1: close (fds[0]); close (fds[1]); p11_message_err (errno, "failed to fork for remote"); return CKR_DEVICE_ERROR; /* Child */ case 0: if (dup2 (fds[1], STDIN_FILENO) < 0 || dup2 (fds[1], STDOUT_FILENO) < 0) { errn = errno; p11_message_err (errn, "couldn't dup file descriptors in remote child"); _exit (errn); } /* Close file descriptors, except for above on exec */ max_fd = STDERR_FILENO + 1; fdwalk (set_cloexec_on_fd, &max_fd); execvp (rex->argv->elem[0], (char **)rex->argv->elem); errn = errno; p11_message_err (errn, "couldn't execute program for rpc: %s", (char *)rex->argv->elem[0]); _exit (errn); /* The parent */ default: break; } close (fds[1]); rex->pid = pid; rex->base.socket = rpc_socket_new (fds[0]); return_val_if_fail (rex->base.socket != NULL, CKR_GENERAL_ERROR); return CKR_OK; } static void rpc_exec_free (void *data) { rpc_exec *rex = data; rpc_exec_disconnect (data, NULL); rpc_transport_uninit (&rex->base); p11_array_free (rex->argv); free (rex); } static void on_argv_parsed (char *argument, void *data) { p11_array *argv = data; if (!p11_array_push (argv, strdup (argument))) return_if_reached (); } static p11_rpc_transport * rpc_exec_init (const char *remote, const char *name) { p11_array *argv; rpc_exec *rex; argv = p11_array_new (free); if (!p11_argv_parse (remote, on_argv_parsed, argv) || argv->num < 1) { p11_message ("invalid remote command line: %s", remote); p11_array_free (argv); return NULL; } rex = calloc (1, sizeof (rpc_exec)); return_val_if_fail (rex != NULL, NULL); p11_array_push (argv, NULL); rex->argv = argv; rex->base.vtable.connect = rpc_exec_connect; rex->base.vtable.disconnect = rpc_exec_disconnect; rex->base.vtable.transport = rpc_transport_buffer; rpc_transport_init (&rex->base, name, rpc_exec_free); p11_debug ("initialized rpc exec: %s", remote); return &rex->base; } #endif /* OS_UNIX */ p11_rpc_transport * p11_rpc_transport_new (p11_virtual *virt, const char *remote, const char *name) { p11_rpc_transport *rpc = NULL; return_val_if_fail (virt != NULL, NULL); return_val_if_fail (remote != NULL, NULL); return_val_if_fail (name != NULL, NULL); #ifdef OS_WIN32 p11_message ("Windows not yet supported for remote"); return NULL; #endif /* This is a command we can execute */ if (remote[0] == '|') { rpc = rpc_exec_init (remote + 1, name); } else { p11_message ("remote not supported: %s", remote); return NULL; } if (!p11_rpc_client_init (virt, &rpc->vtable)) return_val_if_reached (NULL); return rpc; } void p11_rpc_transport_free (void *data) { p11_rpc_transport *rpc = data; if (rpc != NULL) { assert (rpc->destroyer); (rpc->destroyer) (data); } }