thodg/got/lib/privsep.c

Branch : - branch - main - tag - 0.1 0.10 0.11 0.12 0.13 0.14 0.15 0.16 0.17 0.18 0.19 0.2 0.20 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 0.30 0.31 0.32 0.33 0.34 0.35 0.36 0.37 0.38 0.39 0.4 0.40 0.41 0.42 0.43 0.44 0.45 0.46 0.47 0.48 0.49 0.5 0.50 0.51 0.52 0.53 0.54 0.55 0.56 0.57 0.58 0.59 0.6 0.60 0.61 0.62 0.63 0.64 0.65 0.66 0.67 0.68 0.69 0.7 0.70 0.71 0.72 0.8 0.9

• Show log

  Commit

• Author : Stefan Sperling
  Date : 2018-04-23 15:38:35
  Hash : bff6ca00
  Message : read commit objects with privsep

• lib/privsep.c

• /*
   * Copyright (c) 2018 Stefan Sperling <stsp@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/types.h>
  #include <sys/queue.h>
  #include <sys/uio.h>
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <errno.h>
  #include <stdint.h>
  #include <poll.h>
  #include <imsg.h>
  #include <sha1.h>
  #include <zlib.h>
  
  #include "got_object.h"
  #include "got_error.h"
  
  #include "got_lib_sha1.h"
  #include "got_lib_delta.h"
  #include "got_lib_zbuf.h"
  #include "got_lib_object.h"
  #include "got_lib_privsep.h"
  
  #ifndef MIN
  #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
  #endif
  
  static const struct got_error *
  poll_fd(int fd, int events, int timeout)
  {
  	struct pollfd pfd[1];
  	int n;
  
  	pfd[0].fd = fd;
  	pfd[0].events = events;
  
  	n = poll(pfd, 1, timeout);
  	if (n == -1)
  		return got_error_from_errno();
  	if (n == 0)
  		return got_error(GOT_ERR_TIMEOUT);
  	if (pfd[0].revents & (POLLERR | POLLNVAL))
  		return got_error_from_errno();
  	if (pfd[0].revents & (events | POLLHUP))
  		return NULL;
  
  	return got_error(GOT_ERR_INTERRUPT);
  }
  
  static const struct got_error *
  recv_one_imsg(struct imsg *imsg, struct imsgbuf *ibuf, size_t min_datalen)
  {
  	const struct got_error *err;
  	ssize_t n, m;
  
  	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
  	if (err)
  		return err;
  
  	n = imsg_read(ibuf);
  	if (n == -1) {
  		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
  			return got_error(GOT_ERR_PRIVSEP_NO_FD);
  		return got_error(GOT_ERR_PRIVSEP_READ);
  	}
  	if (n == 0)
  		return got_error(GOT_ERR_PRIVSEP_PIPE);
  
  	m = imsg_get(ibuf, imsg);
  	if (m == 0)
  		return got_error(GOT_ERR_PRIVSEP_READ);
  
  	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
  		return got_error(GOT_ERR_PRIVSEP_LEN);
  
  	return NULL;
  }
  
  static const struct got_error *
  recv_imsg_error(struct imsg *imsg, size_t datalen)
  {
  	struct got_imsg_error ierr;
  
  	if (datalen != sizeof(ierr))
  		return got_error(GOT_ERR_PRIVSEP_LEN);
  
  	memcpy(&ierr, imsg->data, sizeof(ierr));
  	if (ierr.code == GOT_ERR_ERRNO) {
  		static struct got_error serr;
  		serr.code = GOT_ERR_ERRNO;
  		serr.msg = strerror(ierr.errno_code);
  		return &serr;
  	}
  
  	return got_error(ierr.code);
  }
  
  /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
  void
  got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
  {
  	const struct got_error *poll_err;
  	struct got_imsg_error ierr;
  	int ret;
  
  	ierr.code = err->code;
  	if (err->code == GOT_ERR_ERRNO)
  		ierr.errno_code = errno;
  	else
  		ierr.errno_code = 0;
  	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
  	if (ret != -1) {
  		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
  		    getprogname(), err->code, err->msg, strerror(errno));
  		return;
  	}
  
  	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
  	if (poll_err) {
  		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
  		    getprogname(), err->code, err->msg, poll_err->msg);
  		return;
  	}
  
  	ret = imsg_flush(ibuf);
  	if (ret == -1) {
  		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
  		    getprogname(), err->code, err->msg, strerror(errno));
  		return;
  	}
  }
  
  const struct got_error *
  got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj, int ndeltas)
  {
  	const struct got_error *err = NULL;
  	struct got_imsg_object iobj;
  
  	iobj.type = obj->type;
  	iobj.flags = obj->flags;
  	iobj.hdrlen = obj->hdrlen;
  	iobj.size = obj->size;
  	iobj.ndeltas = ndeltas;
  
  	if (ndeltas > 0) {
  		/* TODO: Handle deltas */
  	}
  
  	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
  	    == -1)
  		return got_error_from_errno();
  
  	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
  	if (err)
  		return err;
  
  	if (imsg_flush(ibuf) == -1)
  		return got_error_from_errno();
  
  	return NULL;
  }
  
  const struct got_error *
  got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
  {
  	const struct got_error *err = NULL;
  	struct imsg imsg;
  	struct got_imsg_object iobj;
  	size_t datalen;
  	int i;
  	const size_t min_datalen =
  	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
  
  	*obj = NULL;
  
  	err = recv_one_imsg(&imsg, ibuf, min_datalen);
  	if (err)
  		return err;
  
  	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
  
  	switch (imsg.hdr.type) {
  	case GOT_IMSG_ERROR:
  		err = recv_imsg_error(&imsg, datalen);
  		break;
  	case GOT_IMSG_OBJECT:
  		if (datalen != sizeof(iobj)) {
  			err = got_error(GOT_ERR_PRIVSEP_LEN);
  			break;
  		}
  
  		memcpy(&iobj, imsg.data, sizeof(iobj));
  		if (iobj.ndeltas < 0 ||
  		    iobj.ndeltas > GOT_DELTA_CHAIN_RECURSION_MAX) {
  			err = got_error(GOT_ERR_PRIVSEP_LEN);
  			break;
  		}
  
  		*obj = calloc(1, sizeof(**obj));
  		if (*obj == NULL) {
  			err = got_error_from_errno();
  			break;
  		}
  
  		(*obj)->type = iobj.type;
  		(*obj)->hdrlen = iobj.hdrlen;
  		(*obj)->size = iobj.size;
  		for (i = 0; i < iobj.ndeltas; i++) {
  			/* TODO: Handle deltas */
  		}
  		break;
  	default:
  		err = got_error(GOT_ERR_PRIVSEP_MSG);
  		break;
  	}
  
  	imsg_free(&imsg);
  
  	return err;
  }
  
  const struct got_error *
  got_privsep_send_commit_obj(struct imsgbuf *ibuf, struct got_commit_object *commit)
  {
  	const struct got_error *err = NULL;
  	struct got_imsg_commit_object icommit;
  	uint8_t *buf;
  	size_t len, total;
  	struct got_parent_id *pid;
  
  	if (got_sha1_digest_to_str(commit->tree_id->sha1, icommit.tree_id,
  	    sizeof(icommit.tree_id)) == NULL)
  			return got_error(GOT_ERR_BAD_OBJ_ID_STR);
  	icommit.author_len = strlen(commit->author);
  	icommit.committer_len = strlen(commit->committer);
  	icommit.logmsg_len = strlen(commit->logmsg);
  	icommit.nparents = commit->nparents;
  
  	total = sizeof(icommit) + icommit.author_len +
  	    icommit.committer_len + icommit.logmsg_len +
  	    icommit.nparents * (SHA1_DIGEST_STRING_LENGTH);
  	/* XXX TODO support very large log messages properly */
  	if (total > MAX_IMSGSIZE)
  		return got_error(GOT_ERR_NO_SPACE);
  
  	buf = malloc(total);
  	if (buf == NULL)
  		return got_error_from_errno();
  
  	len = 0;
  	memcpy(buf + len, &icommit, sizeof(icommit));
  	len += sizeof(icommit);
  	memcpy(buf + len, commit->author, icommit.author_len);
  	len += icommit.author_len;
  	memcpy(buf + len, commit->committer, icommit.committer_len);
  	len += icommit.committer_len;
  	memcpy(buf + len, commit->logmsg, icommit.logmsg_len);
  	len += icommit.logmsg_len;
  	SIMPLEQ_FOREACH(pid, &commit->parent_ids, entry) {
  		char id_str[SHA1_DIGEST_STRING_LENGTH];
  		if (got_sha1_digest_to_str(pid->id->sha1, id_str,
  		    sizeof(id_str)) == NULL) {
  			err = got_error(GOT_ERR_BAD_OBJ_ID_STR);
  			goto done;
  		}
  		memcpy(buf + len, id_str, SHA1_DIGEST_STRING_LENGTH);
  		len += SHA1_DIGEST_STRING_LENGTH;
  	}
  
  	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
  		err = got_error_from_errno();
  		goto done;
  	}
  
  	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
  	if (err)
  		goto done;
  
  	if (imsg_flush(ibuf) == -1) {
  		err = got_error_from_errno();
  		goto done;
  	}
  
  done:
  	free(buf);
  	return err;
  }
  const struct got_error *
  got_privsep_recv_commit_obj(struct got_commit_object **commit,
      struct imsgbuf *ibuf)
  {
  	const struct got_error *err = NULL;
  	struct imsg imsg;
  	struct got_imsg_commit_object icommit;
  	size_t len, datalen;
  	int i;
  	const size_t min_datalen =
  	    MIN(sizeof(struct got_imsg_error),
  	    sizeof(struct got_imsg_commit_object));
  	uint8_t *data;
  
  	*commit = NULL;
  
  	err = recv_one_imsg(&imsg, ibuf, min_datalen);
  	if (err)
  		return err;
  
  	data = imsg.data;
  	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
  	len = 0;
  
  	switch (imsg.hdr.type) {
  	case GOT_IMSG_ERROR:
  		err = recv_imsg_error(&imsg, datalen);
  		break;
  	case GOT_IMSG_COMMIT:
  		if (datalen < sizeof(icommit)) {
  			err = got_error(GOT_ERR_PRIVSEP_LEN);
  			break;
  		}
  
  		memcpy(&icommit, data, sizeof(icommit));
  		if (datalen != sizeof(icommit) + icommit.author_len +
  		    icommit.committer_len + icommit.logmsg_len +
  		    icommit.nparents * (SHA1_DIGEST_STRING_LENGTH)) {
  			err = got_error(GOT_ERR_PRIVSEP_LEN);
  			break;
  		}
  		if (icommit.nparents < 0) {
  			err = got_error(GOT_ERR_PRIVSEP_LEN);
  			break;
  		}
  		len += sizeof(icommit);
  
  		*commit = got_object_commit_alloc_partial();
  		if (*commit == NULL) {
  			err = got_error_from_errno();
  			break;
  		}
  
  		if (!got_parse_sha1_digest((*commit)->tree_id->sha1,
  		    icommit.tree_id)) {
  			err = got_error(GOT_ERR_BAD_OBJ_DATA);
  			break;
  		}
  
  		if (icommit.author_len == 0) {
  			(*commit)->author = strdup("");
  			if ((*commit)->author == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  		} else {
  			(*commit)->author = malloc(icommit.author_len + 1);
  			if ((*commit)->author == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  			memcpy((*commit)->author, data + len,
  			    icommit.author_len);
  			(*commit)->author[icommit.author_len] = '\0';
  		}
  		len += icommit.author_len;
  
  		if (icommit.committer_len == 0) {
  			(*commit)->committer = strdup("");
  			if ((*commit)->committer == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  		} else {
  			(*commit)->committer =
  			    malloc(icommit.committer_len + 1);
  			if ((*commit)->committer == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  			memcpy((*commit)->committer, data + len,
  			    icommit.committer_len);
  			(*commit)->committer[icommit.committer_len] = '\0';
  		}
  		len += icommit.committer_len;
  
  		if (icommit.logmsg_len == 0) {
  			(*commit)->logmsg = strdup("");
  			if ((*commit)->logmsg == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  		} else {
  			(*commit)->logmsg = malloc(icommit.logmsg_len + 1);
  			if ((*commit)->logmsg == NULL) {
  				err = got_error_from_errno();
  				break;
  			}
  			memcpy((*commit)->logmsg, data + len,
  			    icommit.logmsg_len);
  			(*commit)->logmsg[icommit.logmsg_len] = '\0';
  		}
  		len += icommit.logmsg_len;
  
  		for (i = 0; i < icommit.nparents; i++) {
  			char id_str[SHA1_DIGEST_STRING_LENGTH];
  			memcpy(id_str, data + len +
  			    i * SHA1_DIGEST_STRING_LENGTH, sizeof(id_str));
  			id_str[SHA1_DIGEST_STRING_LENGTH - 1] = '\0';
  			err = got_object_commit_add_parent(*commit, id_str);
  			if (err)
  				break;
  		}
  		break;
  	default:
  		err = got_error(GOT_ERR_PRIVSEP_MSG);
  		break;
  	}
  
  	imsg_free(&imsg);
  
  	return err;
  }