diff options
Diffstat (limited to 'usr.bin/tee/tee.c')
| -rw-r--r-- | usr.bin/tee/tee.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/usr.bin/tee/tee.c b/usr.bin/tee/tee.c new file mode 100644 index 000000000000..fb73b311a31b --- /dev/null +++ b/usr.bin/tee/tee.c @@ -0,0 +1,193 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 1988, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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. + */ + +#include <sys/types.h> +#include <sys/capsicum.h> +#include <sys/queue.h> +#include <sys/socket.h> +#include <sys/stat.h> +#include <sys/un.h> + +#include <capsicum_helpers.h> +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +struct entry { + int fd; + const char *name; + STAILQ_ENTRY(entry) entries; +}; +static STAILQ_HEAD(, entry) head = STAILQ_HEAD_INITIALIZER(head); + +static void add(int, const char *); +static int tee_open(const char *, int); +static void usage(void) __dead2; + +int +main(int argc, char *argv[]) +{ + char *bp, *buf; + struct entry *p; + int append, ch, exitval, fd, n, oflags, rval, wval; +#define BSIZE (8 * 1024) + + append = 0; + while ((ch = getopt(argc, argv, "ai")) != -1) + switch((char)ch) { + case 'a': + append = 1; + break; + case 'i': + (void)signal(SIGINT, SIG_IGN); + break; + case '?': + default: + usage(); + } + argv += optind; + argc -= optind; + + if ((buf = malloc(BSIZE)) == NULL) + err(1, "malloc"); + + if (caph_limit_stdin() == -1 || caph_limit_stderr() == -1) + err(EXIT_FAILURE, "unable to limit stdio"); + + add(STDOUT_FILENO, "stdout"); + + oflags = O_WRONLY | O_CREAT; + if (append) + oflags |= O_APPEND; + else + oflags |= O_TRUNC; + + for (exitval = 0; *argv; ++argv) { + if ((fd = tee_open(*argv, oflags)) < 0) { + warn("%s", *argv); + exitval = 1; + } else { + add(fd, *argv); + } + } + + if (caph_enter() < 0) + err(EXIT_FAILURE, "unable to enter capability mode"); + while ((rval = read(STDIN_FILENO, buf, BSIZE)) > 0) + STAILQ_FOREACH(p, &head, entries) { + n = rval; + bp = buf; + do { + if ((wval = write(p->fd, bp, n)) == -1) { + warn("%s", p->name); + exitval = 1; + break; + } + bp += wval; + } while (n -= wval); + } + if (rval < 0) + err(1, "read"); + exit(exitval); +} + +static void +usage(void) +{ + (void)fprintf(stderr, "usage: tee [-ai] [file ...]\n"); + exit(1); +} + +static void +add(int fd, const char *name) +{ + struct entry *p; + cap_rights_t rights; + + if (fd == STDOUT_FILENO) { + if (caph_limit_stdout() == -1) + err(EXIT_FAILURE, "unable to limit stdout"); + } else { + cap_rights_init(&rights, CAP_WRITE, CAP_FSTAT); + if (caph_rights_limit(fd, &rights) < 0) + err(EXIT_FAILURE, "unable to limit rights"); + } + + if ((p = malloc(sizeof(struct entry))) == NULL) + err(1, "malloc"); + p->fd = fd; + p->name = name; + STAILQ_INSERT_HEAD(&head, p, entries); +} + +static int +tee_open(const char *path, int oflags) +{ + struct sockaddr_un sun = { .sun_family = AF_UNIX }; + size_t pathlen; + int fd; + + if ((fd = open(path, oflags, DEFFILEMODE)) >= 0) + return (fd); + + if (errno != EOPNOTSUPP) + return (-1); + + pathlen = strnlen(path, sizeof(sun.sun_path)); + if (pathlen >= sizeof(sun.sun_path)) + goto failed; + + /* + * For EOPNOTSUPP, we'll try again as a unix(4) socket. Any errors here + * we'll just surface as the original EOPNOTSUPP since they may not have + * intended for this. + */ + fd = socket(PF_UNIX, SOCK_STREAM, 0); + if (fd < 0) + goto failed; + + (void)strlcpy(&sun.sun_path[0], path, sizeof(sun.sun_path)); + sun.sun_len = SUN_LEN(&sun); + + if (connect(fd, (const struct sockaddr *)&sun, sun.sun_len) == 0) + return (fd); + +failed: + if (fd >= 0) + close(fd); + errno = EOPNOTSUPP; + return (-1); +} |