diff options
author | Tiago Cunha <tcunha@gmx.com> | 2009-08-14 21:04:04 +0000 |
---|---|---|
committer | Tiago Cunha <tcunha@gmx.com> | 2009-08-14 21:04:04 +0000 |
commit | a9b6bfdddd570753e52dca73169f70864502c38c (patch) | |
tree | bc259ba79ba2ddddd5579857ccaad69eef5d55d4 /compat | |
parent | a604dfbb979c994ee7fb068416e0b60c95ce2198 (diff) |
Sync OpenBSD patchset 243:
Switch tmux to use imsg. This is the last major change to make the
client-server protocol more resilient and make the protocol versioning work
properly. In future, the only things requiring a protocol version bump will be
changes in the message structs, and (when both client and server have this
change) mixing different versions should nicely report an error message.
As a side effect this also makes the code tidier, fixes a problem with the way
errors reported during server startup were handled, and supports fd passing
(which will be used in future).
Looked over by eric@, thanks.
Please note that mixing a client with this change with an older server or vice
versa may cause tmux to crash or hang - tmux should be completely exited before
upgrading.
Diffstat (limited to 'compat')
-rw-r--r-- | compat/imsg-buffer.c | 305 | ||||
-rw-r--r-- | compat/imsg.c | 271 | ||||
-rw-r--r-- | compat/imsg.h | 108 |
3 files changed, 684 insertions, 0 deletions
diff --git a/compat/imsg-buffer.c b/compat/imsg-buffer.c new file mode 100644 index 00000000..ef380ab6 --- /dev/null +++ b/compat/imsg-buffer.c @@ -0,0 +1,305 @@ +/* $OpenBSD: imsg-buffer.c,v 1.1 2009/08/11 17:18:35 nicm Exp $ */ + +/* + * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/param.h> +#include <sys/queue.h> +#include <sys/socket.h> +#include <sys/uio.h> + +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "imsg.h" + +int buf_realloc(struct buf *, size_t); +void buf_enqueue(struct msgbuf *, struct buf *); +void buf_dequeue(struct msgbuf *, struct buf *); + +struct buf * +buf_open(size_t len) +{ + struct buf *buf; + + if ((buf = calloc(1, sizeof(struct buf))) == NULL) + return (NULL); + if ((buf->buf = malloc(len)) == NULL) { + free(buf); + return (NULL); + } + buf->size = buf->max = len; + buf->fd = -1; + + return (buf); +} + +struct buf * +buf_dynamic(size_t len, size_t max) +{ + struct buf *buf; + + if (max < len) + return (NULL); + + if ((buf = buf_open(len)) == NULL) + return (NULL); + + if (max > 0) + buf->max = max; + + return (buf); +} + +int +buf_realloc(struct buf *buf, size_t len) +{ + u_char *b; + + /* on static buffers max is eq size and so the following fails */ + if (buf->wpos + len > buf->max) { + errno = ENOMEM; + return (-1); + } + + b = realloc(buf->buf, buf->wpos + len); + if (b == NULL) + return (-1); + buf->buf = b; + buf->size = buf->wpos + len; + + return (0); +} + +int +buf_add(struct buf *buf, const void *data, size_t len) +{ + if (buf->wpos + len > buf->size) + if (buf_realloc(buf, len) == -1) + return (-1); + + memcpy(buf->buf + buf->wpos, data, len); + buf->wpos += len; + return (0); +} + +void * +buf_reserve(struct buf *buf, size_t len) +{ + void *b; + + if (buf->wpos + len > buf->size) + if (buf_realloc(buf, len) == -1) + return (NULL); + + b = buf->buf + buf->wpos; + buf->wpos += len; + return (b); +} + +void * +buf_seek(struct buf *buf, size_t pos, size_t len) +{ + /* only allowed to seek in already written parts */ + if (pos + len > buf->wpos) + return (NULL); + + return (buf->buf + pos); +} + +size_t +buf_size(struct buf *buf) +{ + return (buf->wpos); +} + +size_t +buf_left(struct buf *buf) +{ + return (buf->max - buf->wpos); +} + +void +buf_close(struct msgbuf *msgbuf, struct buf *buf) +{ + buf_enqueue(msgbuf, buf); +} + +int +buf_write(struct msgbuf *msgbuf) +{ + struct iovec iov[IOV_MAX]; + struct buf *buf, *next; + unsigned int i = 0; + ssize_t n; + + bzero(&iov, sizeof(iov)); + TAILQ_FOREACH(buf, &msgbuf->bufs, entry) { + if (i >= IOV_MAX) + break; + iov[i].iov_base = buf->buf + buf->rpos; + iov[i].iov_len = buf->wpos - buf->rpos; + i++; + } + + if ((n = writev(msgbuf->fd, iov, i)) == -1) { + if (errno == EAGAIN || errno == ENOBUFS || + errno == EINTR) /* try later */ + return (0); + else + return (-1); + } + + if (n == 0) { /* connection closed */ + errno = 0; + return (-2); + } + + for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0; + buf = next) { + next = TAILQ_NEXT(buf, entry); + if (buf->rpos + n >= buf->wpos) { + n -= buf->wpos - buf->rpos; + buf_dequeue(msgbuf, buf); + } else { + buf->rpos += n; + n = 0; + } + } + + return (0); +} + +void +buf_free(struct buf *buf) +{ + free(buf->buf); + free(buf); +} + +void +msgbuf_init(struct msgbuf *msgbuf) +{ + msgbuf->queued = 0; + msgbuf->fd = -1; + TAILQ_INIT(&msgbuf->bufs); +} + +void +msgbuf_clear(struct msgbuf *msgbuf) +{ + struct buf *buf; + + while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL) + buf_dequeue(msgbuf, buf); +} + +int +msgbuf_write(struct msgbuf *msgbuf) +{ + struct iovec iov[IOV_MAX]; + struct buf *buf, *next; + unsigned int i = 0; + ssize_t n; + struct msghdr msg; + struct cmsghdr *cmsg; + union { + struct cmsghdr hdr; + char buf[CMSG_SPACE(sizeof(int))]; + } cmsgbuf; + + bzero(&iov, sizeof(iov)); + bzero(&msg, sizeof(msg)); + TAILQ_FOREACH(buf, &msgbuf->bufs, entry) { + if (i >= IOV_MAX) + break; + iov[i].iov_base = buf->buf + buf->rpos; + iov[i].iov_len = buf->wpos - buf->rpos; + i++; + if (buf->fd != -1) + break; + } + + msg.msg_iov = iov; + msg.msg_iovlen = i; + + if (buf != NULL && buf->fd != -1) { + msg.msg_control = (caddr_t)&cmsgbuf.buf; + msg.msg_controllen = sizeof(cmsgbuf.buf); + cmsg = CMSG_FIRSTHDR(&msg); + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + *(int *)CMSG_DATA(cmsg) = buf->fd; + } + + if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) { + if (errno == EAGAIN || errno == ENOBUFS || + errno == EINTR) /* try later */ + return (0); + else + return (-1); + } + + if (n == 0) { /* connection closed */ + errno = 0; + return (-2); + } + + /* + * assumption: fd got sent if sendmsg sent anything + * this works because fds are passed one at a time + */ + if (buf != NULL && buf->fd != -1) { + close(buf->fd); + buf->fd = -1; + } + + for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0; + buf = next) { + next = TAILQ_NEXT(buf, entry); + if (buf->rpos + n >= buf->wpos) { + n -= buf->wpos - buf->rpos; + buf_dequeue(msgbuf, buf); + } else { + buf->rpos += n; + n = 0; + } + } + + return (0); +} + +void +buf_enqueue(struct msgbuf *msgbuf, struct buf *buf) +{ + TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry); + msgbuf->queued++; +} + +void +buf_dequeue(struct msgbuf *msgbuf, struct buf *buf) +{ + TAILQ_REMOVE(&msgbuf->bufs, buf, entry); + + if (buf->fd != -1) + close(buf->fd); + + msgbuf->queued--; + buf_free(buf); +} diff --git a/compat/imsg.c b/compat/imsg.c new file mode 100644 index 00000000..4ba37f42 --- /dev/null +++ b/compat/imsg.c @@ -0,0 +1,271 @@ +/* $OpenBSD: imsg.c,v 1.1 2009/08/11 17:18:35 nicm Exp $ */ + +/* + * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/param.h> +#include <sys/queue.h> +#include <sys/socket.h> +#include <sys/uio.h> + +#include <errno.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "imsg.h" + +int imsg_get_fd(struct imsgbuf *); + +void +imsg_init(struct imsgbuf *ibuf, int fd) +{ + msgbuf_init(&ibuf->w); + bzero(&ibuf->r, sizeof(ibuf->r)); + ibuf->fd = fd; + ibuf->w.fd = fd; + ibuf->pid = getpid(); + TAILQ_INIT(&ibuf->fds); +} + +ssize_t +imsg_read(struct imsgbuf *ibuf) +{ + struct msghdr msg; + struct cmsghdr *cmsg; + union { + struct cmsghdr hdr; + char buf[CMSG_SPACE(sizeof(int) * 16)]; + } cmsgbuf; + struct iovec iov; + ssize_t n; + int fd; + struct imsg_fd *ifd; + + bzero(&msg, sizeof(msg)); + + iov.iov_base = ibuf->r.buf + ibuf->r.wpos; + iov.iov_len = sizeof(ibuf->r.buf) - ibuf->r.wpos; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = &cmsgbuf.buf; + msg.msg_controllen = sizeof(cmsgbuf.buf); + + if ((n = recvmsg(ibuf->fd, &msg, 0)) == -1) { + if (errno != EINTR && errno != EAGAIN) { + return (-1); + } + return (-2); + } + + ibuf->r.wpos += n; + + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; + cmsg = CMSG_NXTHDR(&msg, cmsg)) { + if (cmsg->cmsg_level == SOL_SOCKET && + cmsg->cmsg_type == SCM_RIGHTS) { + fd = (*(int *)CMSG_DATA(cmsg)); + if ((ifd = calloc(1, sizeof(struct imsg_fd))) == NULL) { + /* XXX: this return can leak */ + return (-1); + } + ifd->fd = fd; + TAILQ_INSERT_TAIL(&ibuf->fds, ifd, entry); + } + /* we do not handle other ctl data level */ + } + + return (n); +} + +ssize_t +imsg_get(struct imsgbuf *ibuf, struct imsg *imsg) +{ + size_t av, left, datalen; + + av = ibuf->r.wpos; + + if (IMSG_HEADER_SIZE > av) + return (0); + + memcpy(&imsg->hdr, ibuf->r.buf, sizeof(imsg->hdr)); + if (imsg->hdr.len < IMSG_HEADER_SIZE || + imsg->hdr.len > MAX_IMSGSIZE) { + errno = ERANGE; + return (-1); + } + if (imsg->hdr.len > av) + return (0); + datalen = imsg->hdr.len - IMSG_HEADER_SIZE; + ibuf->r.rptr = ibuf->r.buf + IMSG_HEADER_SIZE; + if ((imsg->data = malloc(datalen)) == NULL) + return (-1); + + if (imsg->hdr.flags & IMSGF_HASFD) + imsg->fd = imsg_get_fd(ibuf); + else + imsg->fd = -1; + + memcpy(imsg->data, ibuf->r.rptr, datalen); + + if (imsg->hdr.len < av) { + left = av - imsg->hdr.len; + memmove(&ibuf->r.buf, ibuf->r.buf + imsg->hdr.len, left); + ibuf->r.wpos = left; + } else + ibuf->r.wpos = 0; + + return (datalen + IMSG_HEADER_SIZE); +} + +int +imsg_compose(struct imsgbuf *ibuf, u_int32_t type, u_int32_t peerid, + pid_t pid, int fd, void *data, u_int16_t datalen) +{ + struct buf *wbuf; + + if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL) + return (-1); + + if (imsg_add(wbuf, data, datalen) == -1) + return (-1); + + wbuf->fd = fd; + + imsg_close(ibuf, wbuf); + + return (1); +} + +int +imsg_composev(struct imsgbuf *ibuf, u_int32_t type, u_int32_t peerid, + pid_t pid, int fd, const struct iovec *iov, int iovcnt) +{ + struct buf *wbuf; + int i, datalen = 0; + + for (i = 0; i < iovcnt; i++) + datalen += iov[i].iov_len; + + if ((wbuf = imsg_create(ibuf, type, peerid, pid, datalen)) == NULL) + return (-1); + + for (i = 0; i < iovcnt; i++) + if (imsg_add(wbuf, iov[i].iov_base, iov[i].iov_len) == -1) + return (-1); + + wbuf->fd = fd; + + imsg_close(ibuf, wbuf); + + return (1); +} + +/* ARGSUSED */ +struct buf * +imsg_create(struct imsgbuf *ibuf, u_int32_t type, u_int32_t peerid, + pid_t pid, u_int16_t datalen) +{ + struct buf *wbuf; + struct imsg_hdr hdr; + + datalen += IMSG_HEADER_SIZE; + if (datalen > MAX_IMSGSIZE) { + errno = ERANGE; + return (NULL); + } + + hdr.type = type; + hdr.flags = 0; + hdr.peerid = peerid; + if ((hdr.pid = pid) == 0) + hdr.pid = ibuf->pid; + if ((wbuf = buf_dynamic(datalen, MAX_IMSGSIZE)) == NULL) { + return (NULL); + } + if (imsg_add(wbuf, &hdr, sizeof(hdr)) == -1) + return (NULL); + + return (wbuf); +} + +int +imsg_add(struct buf *msg, void *data, u_int16_t datalen) +{ + if (datalen) + if (buf_add(msg, data, datalen) == -1) { + buf_free(msg); + return (-1); + } + return (datalen); +} + +void +imsg_close(struct imsgbuf *ibuf, struct buf *msg) +{ + struct imsg_hdr *hdr; + + hdr = (struct imsg_hdr *)msg->buf; + + hdr->flags &= ~IMSGF_HASFD; + if (msg->fd != -1) + hdr->flags |= IMSGF_HASFD; + + hdr->len = (u_int16_t)msg->wpos; + + buf_close(&ibuf->w, msg); +} + +void +imsg_free(struct imsg *imsg) +{ + free(imsg->data); +} + +int +imsg_get_fd(struct imsgbuf *ibuf) +{ + int fd; + struct imsg_fd *ifd; + + if ((ifd = TAILQ_FIRST(&ibuf->fds)) == NULL) + return (-1); + + fd = ifd->fd; + TAILQ_REMOVE(&ibuf->fds, ifd, entry); + free(ifd); + + return (fd); +} + +int +imsg_flush(struct imsgbuf *ibuf) +{ + while (ibuf->w.queued) + if (msgbuf_write(&ibuf->w) < 0) + return (-1); + return (0); +} + +void +imsg_clear(struct imsgbuf *ibuf) +{ + int fd; + + msgbuf_clear(&ibuf->w); + while ((fd = imsg_get_fd(ibuf)) != -1) + close(fd); +} diff --git a/compat/imsg.h b/compat/imsg.h new file mode 100644 index 00000000..329904a1 --- /dev/null +++ b/compat/imsg.h @@ -0,0 +1,108 @@ +/* $OpenBSD: imsg.h,v 1.1 2009/08/11 17:18:35 nicm Exp $ */ + +/* + * Copyright (c) 2006, 2007 Pierre-Yves Ritschard <pyr@openbsd.org> + * Copyright (c) 2006, 2007, 2008 Reyk Floeter <reyk@openbsd.org> + * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/tree.h> + +#define READ_BUF_SIZE 65535 +#define IMSG_HEADER_SIZE sizeof(struct imsg_hdr) +#define MAX_IMSGSIZE 16384 + +struct buf { + TAILQ_ENTRY(buf) entry; + u_char *buf; + size_t size; + size_t max; + size_t wpos; + size_t rpos; + int fd; +}; + +struct msgbuf { + TAILQ_HEAD(, buf) bufs; + u_int32_t queued; + int fd; +}; + +struct buf_read { + u_char buf[READ_BUF_SIZE]; + u_char *rptr; + size_t wpos; +}; + +struct imsg_fd { + TAILQ_ENTRY(imsg_fd) entry; + int fd; +}; + +struct imsgbuf { + TAILQ_HEAD(, imsg_fd) fds; + struct buf_read r; + struct msgbuf w; + int fd; + pid_t pid; +}; + +#define IMSGF_HASFD 1 + +struct imsg_hdr { + u_int32_t type; + u_int16_t len; + u_int16_t flags; + u_int32_t peerid; + u_int32_t pid; +}; + +struct imsg { + struct imsg_hdr hdr; + int fd; + void *data; +}; + + +/* buffer.c */ +struct buf *buf_open(size_t); +struct buf *buf_dynamic(size_t, size_t); +int buf_add(struct buf *, const void *, size_t); +void *buf_reserve(struct buf *, size_t); +void *buf_seek(struct buf *, size_t, size_t); +size_t buf_size(struct buf *); +size_t buf_left(struct buf *); +void buf_close(struct msgbuf *, struct buf *); +int buf_write(struct msgbuf *); +void buf_free(struct buf *); +void msgbuf_init(struct msgbuf *); +void msgbuf_clear(struct msgbuf *); +int msgbuf_write(struct msgbuf *); + +/* imsg.c */ +void imsg_init(struct imsgbuf *, int); +ssize_t imsg_read(struct imsgbuf *); +ssize_t imsg_get(struct imsgbuf *, struct imsg *); +int imsg_compose(struct imsgbuf *, u_int32_t, u_int32_t, pid_t, + int, void *, u_int16_t); +int imsg_composev(struct imsgbuf *, u_int32_t, u_int32_t, pid_t, + int, const struct iovec *, int); +struct buf *imsg_create(struct imsgbuf *, u_int32_t, u_int32_t, pid_t, + u_int16_t); +int imsg_add(struct buf *, void *, u_int16_t); +void imsg_close(struct imsgbuf *, struct buf *); +void imsg_free(struct imsg *); +int imsg_flush(struct imsgbuf *); +void imsg_clear(struct imsgbuf *); |