diff options
Diffstat (limited to 'src/libsystemd/libsystemd-journal-internal/journal-send.c')
-rw-r--r-- | src/libsystemd/libsystemd-journal-internal/journal-send.c | 559 |
1 files changed, 559 insertions, 0 deletions
diff --git a/src/libsystemd/libsystemd-journal-internal/journal-send.c b/src/libsystemd/libsystemd-journal-internal/journal-send.c new file mode 100644 index 0000000000..b85d9d3c61 --- /dev/null +++ b/src/libsystemd/libsystemd-journal-internal/journal-send.c @@ -0,0 +1,559 @@ +/*** + This file is part of systemd. + + Copyright 2011 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <fcntl.h> +#include <printf.h> +#include <stddef.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <unistd.h> + +#define SD_JOURNAL_SUPPRESS_LOCATION + +#include <systemd/sd-journal.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "io-util.h" +#include "memfd-util.h" +#include "socket-util.h" +#include "stdio-util.h" +#include "string-util.h" +#include "util.h" + +#define SNDBUF_SIZE (8*1024*1024) + +#define ALLOCA_CODE_FUNC(f, func) \ + do { \ + size_t _fl; \ + const char *_func = (func); \ + char **_f = &(f); \ + _fl = strlen(_func) + 1; \ + *_f = alloca(_fl + 10); \ + memcpy(*_f, "CODE_FUNC=", 10); \ + memcpy(*_f + 10, _func, _fl); \ + } while(false) + +/* We open a single fd, and we'll share it with the current process, + * all its threads, and all its subprocesses. This means we need to + * initialize it atomically, and need to operate on it atomically + * never assuming we are the only user */ + +static int journal_fd(void) { + int fd; + static int fd_plus_one = 0; + +retry: + if (fd_plus_one > 0) + return fd_plus_one - 1; + + fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + fd_inc_sndbuf(fd, SNDBUF_SIZE); + + if (!__sync_bool_compare_and_swap(&fd_plus_one, 0, fd+1)) { + safe_close(fd); + goto retry; + } + + return fd; +} + +_public_ int sd_journal_print(int priority, const char *format, ...) { + int r; + va_list ap; + + va_start(ap, format); + r = sd_journal_printv(priority, format, ap); + va_end(ap); + + return r; +} + +_public_ int sd_journal_printv(int priority, const char *format, va_list ap) { + + /* FIXME: Instead of limiting things to LINE_MAX we could do a + C99 variable-length array on the stack here in a loop. */ + + char buffer[8 + LINE_MAX], p[sizeof("PRIORITY=")-1 + DECIMAL_STR_MAX(int) + 1]; + struct iovec iov[2]; + + assert_return(priority >= 0, -EINVAL); + assert_return(priority <= 7, -EINVAL); + assert_return(format, -EINVAL); + + xsprintf(p, "PRIORITY=%i", priority & LOG_PRIMASK); + + memcpy(buffer, "MESSAGE=", 8); + vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap); + + zero(iov); + IOVEC_SET_STRING(iov[0], buffer); + IOVEC_SET_STRING(iov[1], p); + + return sd_journal_sendv(iov, 2); +} + +_printf_(1, 0) static int fill_iovec_sprintf(const char *format, va_list ap, int extra, struct iovec **_iov) { + PROTECT_ERRNO; + int r, n = 0, i = 0, j; + struct iovec *iov = NULL; + + assert(_iov); + + if (extra > 0) { + n = MAX(extra * 2, extra + 4); + iov = malloc0(n * sizeof(struct iovec)); + if (!iov) { + r = -ENOMEM; + goto fail; + } + + i = extra; + } + + while (format) { + struct iovec *c; + char *buffer; + va_list aq; + + if (i >= n) { + n = MAX(i*2, 4); + c = realloc(iov, n * sizeof(struct iovec)); + if (!c) { + r = -ENOMEM; + goto fail; + } + + iov = c; + } + + va_copy(aq, ap); + if (vasprintf(&buffer, format, aq) < 0) { + va_end(aq); + r = -ENOMEM; + goto fail; + } + va_end(aq); + + VA_FORMAT_ADVANCE(format, ap); + + IOVEC_SET_STRING(iov[i++], buffer); + + format = va_arg(ap, char *); + } + + *_iov = iov; + + return i; + +fail: + for (j = 0; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + return r; +} + +_public_ int sd_journal_send(const char *format, ...) { + int r, i, j; + va_list ap; + struct iovec *iov = NULL; + + va_start(ap, format); + i = fill_iovec_sprintf(format, ap, 0, &iov); + va_end(ap); + + if (_unlikely_(i < 0)) { + r = i; + goto finish; + } + + r = sd_journal_sendv(iov, i); + +finish: + for (j = 0; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + return r; +} + +_public_ int sd_journal_sendv(const struct iovec *iov, int n) { + PROTECT_ERRNO; + int fd, r; + _cleanup_close_ int buffer_fd = -1; + struct iovec *w; + uint64_t *l; + int i, j = 0; + struct sockaddr_un sa = { + .sun_family = AF_UNIX, + .sun_path = "/run/systemd/journal/socket", + }; + struct msghdr mh = { + .msg_name = &sa, + .msg_namelen = offsetof(struct sockaddr_un, sun_path) + strlen(sa.sun_path), + }; + ssize_t k; + bool have_syslog_identifier = false; + bool seal = true; + + assert_return(iov, -EINVAL); + assert_return(n > 0, -EINVAL); + + w = newa(struct iovec, n * 5 + 3); + l = newa(uint64_t, n); + + for (i = 0; i < n; i++) { + char *c, *nl; + + if (_unlikely_(!iov[i].iov_base || iov[i].iov_len <= 1)) + return -EINVAL; + + c = memchr(iov[i].iov_base, '=', iov[i].iov_len); + if (_unlikely_(!c || c == iov[i].iov_base)) + return -EINVAL; + + have_syslog_identifier = have_syslog_identifier || + (c == (char *) iov[i].iov_base + 17 && + startswith(iov[i].iov_base, "SYSLOG_IDENTIFIER")); + + nl = memchr(iov[i].iov_base, '\n', iov[i].iov_len); + if (nl) { + if (_unlikely_(nl < c)) + return -EINVAL; + + /* Already includes a newline? Bummer, then + * let's write the variable name, then a + * newline, then the size (64bit LE), followed + * by the data and a final newline */ + + w[j].iov_base = iov[i].iov_base; + w[j].iov_len = c - (char*) iov[i].iov_base; + j++; + + IOVEC_SET_STRING(w[j++], "\n"); + + l[i] = htole64(iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1); + w[j].iov_base = &l[i]; + w[j].iov_len = sizeof(uint64_t); + j++; + + w[j].iov_base = c + 1; + w[j].iov_len = iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1; + j++; + + } else + /* Nothing special? Then just add the line and + * append a newline */ + w[j++] = iov[i]; + + IOVEC_SET_STRING(w[j++], "\n"); + } + + if (!have_syslog_identifier && + string_is_safe(program_invocation_short_name)) { + + /* Implicitly add program_invocation_short_name, if it + * is not set explicitly. We only do this for + * program_invocation_short_name, and nothing else + * since everything else is much nicer to retrieve + * from the outside. */ + + IOVEC_SET_STRING(w[j++], "SYSLOG_IDENTIFIER="); + IOVEC_SET_STRING(w[j++], program_invocation_short_name); + IOVEC_SET_STRING(w[j++], "\n"); + } + + fd = journal_fd(); + if (_unlikely_(fd < 0)) + return fd; + + mh.msg_iov = w; + mh.msg_iovlen = j; + + k = sendmsg(fd, &mh, MSG_NOSIGNAL); + if (k >= 0) + return 0; + + /* Fail silently if the journal is not available */ + if (errno == ENOENT) + return 0; + + if (errno != EMSGSIZE && errno != ENOBUFS) + return -errno; + + /* Message doesn't fit... Let's dump the data in a memfd or + * temporary file and just pass a file descriptor of it to the + * other side. + * + * For the temporary files we use /dev/shm instead of /tmp + * here, since we want this to be a tmpfs, and one that is + * available from early boot on and where unprivileged users + * can create files. */ + buffer_fd = memfd_new(NULL); + if (buffer_fd < 0) { + if (buffer_fd == -ENOSYS) { + buffer_fd = open_tmpfile("/dev/shm", O_RDWR | O_CLOEXEC); + if (buffer_fd < 0) + return buffer_fd; + + seal = false; + } else + return buffer_fd; + } + + n = writev(buffer_fd, w, j); + if (n < 0) + return -errno; + + if (seal) { + r = memfd_set_sealed(buffer_fd); + if (r < 0) + return r; + } + + r = send_one_fd_sa(fd, buffer_fd, mh.msg_name, mh.msg_namelen, 0); + if (r == -ENOENT) + /* Fail silently if the journal is not available */ + return 0; + return r; +} + +static int fill_iovec_perror_and_send(const char *message, int skip, struct iovec iov[]) { + PROTECT_ERRNO; + size_t n, k; + + k = isempty(message) ? 0 : strlen(message) + 2; + n = 8 + k + 256 + 1; + + for (;;) { + char buffer[n]; + char* j; + + errno = 0; + j = strerror_r(_saved_errno_, buffer + 8 + k, n - 8 - k); + if (errno == 0) { + char error[sizeof("ERRNO=")-1 + DECIMAL_STR_MAX(int) + 1]; + + if (j != buffer + 8 + k) + memmove(buffer + 8 + k, j, strlen(j)+1); + + memcpy(buffer, "MESSAGE=", 8); + + if (k > 0) { + memcpy(buffer + 8, message, k - 2); + memcpy(buffer + 8 + k - 2, ": ", 2); + } + + xsprintf(error, "ERRNO=%i", _saved_errno_); + + assert_cc(3 == LOG_ERR); + IOVEC_SET_STRING(iov[skip+0], "PRIORITY=3"); + IOVEC_SET_STRING(iov[skip+1], buffer); + IOVEC_SET_STRING(iov[skip+2], error); + + return sd_journal_sendv(iov, skip + 3); + } + + if (errno != ERANGE) + return -errno; + + n *= 2; + } +} + +_public_ int sd_journal_perror(const char *message) { + struct iovec iovec[3]; + + return fill_iovec_perror_and_send(message, 0, iovec); +} + +_public_ int sd_journal_stream_fd(const char *identifier, int priority, int level_prefix) { + union sockaddr_union sa = { + .un.sun_family = AF_UNIX, + .un.sun_path = "/run/systemd/journal/stdout", + }; + _cleanup_close_ int fd = -1; + char *header; + size_t l; + int r; + + assert_return(priority >= 0, -EINVAL); + assert_return(priority <= 7, -EINVAL); + + fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + r = connect(fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path)); + if (r < 0) + return -errno; + + if (shutdown(fd, SHUT_RD) < 0) + return -errno; + + fd_inc_sndbuf(fd, SNDBUF_SIZE); + + if (!identifier) + identifier = ""; + + l = strlen(identifier); + header = alloca(l + 1 + 1 + 2 + 2 + 2 + 2 + 2); + + memcpy(header, identifier, l); + header[l++] = '\n'; + header[l++] = '\n'; /* unit id */ + header[l++] = '0' + priority; + header[l++] = '\n'; + header[l++] = '0' + !!level_prefix; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + + r = loop_write(fd, header, l, false); + if (r < 0) + return r; + + r = fd; + fd = -1; + return r; +} + +_public_ int sd_journal_print_with_location(int priority, const char *file, const char *line, const char *func, const char *format, ...) { + int r; + va_list ap; + + va_start(ap, format); + r = sd_journal_printv_with_location(priority, file, line, func, format, ap); + va_end(ap); + + return r; +} + +_public_ int sd_journal_printv_with_location(int priority, const char *file, const char *line, const char *func, const char *format, va_list ap) { + char buffer[8 + LINE_MAX], p[sizeof("PRIORITY=")-1 + DECIMAL_STR_MAX(int) + 1]; + struct iovec iov[5]; + char *f; + + assert_return(priority >= 0, -EINVAL); + assert_return(priority <= 7, -EINVAL); + assert_return(format, -EINVAL); + + xsprintf(p, "PRIORITY=%i", priority & LOG_PRIMASK); + + memcpy(buffer, "MESSAGE=", 8); + vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap); + + /* func is initialized from __func__ which is not a macro, but + * a static const char[], hence cannot easily be prefixed with + * CODE_FUNC=, hence let's do it manually here. */ + ALLOCA_CODE_FUNC(f, func); + + zero(iov); + IOVEC_SET_STRING(iov[0], buffer); + IOVEC_SET_STRING(iov[1], p); + IOVEC_SET_STRING(iov[2], file); + IOVEC_SET_STRING(iov[3], line); + IOVEC_SET_STRING(iov[4], f); + + return sd_journal_sendv(iov, ELEMENTSOF(iov)); +} + +_public_ int sd_journal_send_with_location(const char *file, const char *line, const char *func, const char *format, ...) { + int r, i, j; + va_list ap; + struct iovec *iov = NULL; + char *f; + + va_start(ap, format); + i = fill_iovec_sprintf(format, ap, 3, &iov); + va_end(ap); + + if (_unlikely_(i < 0)) { + r = i; + goto finish; + } + + ALLOCA_CODE_FUNC(f, func); + + IOVEC_SET_STRING(iov[0], file); + IOVEC_SET_STRING(iov[1], line); + IOVEC_SET_STRING(iov[2], f); + + r = sd_journal_sendv(iov, i); + +finish: + for (j = 3; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + return r; +} + +_public_ int sd_journal_sendv_with_location( + const char *file, const char *line, + const char *func, + const struct iovec *iov, int n) { + + struct iovec *niov; + char *f; + + assert_return(iov, -EINVAL); + assert_return(n > 0, -EINVAL); + + niov = alloca(sizeof(struct iovec) * (n + 3)); + memcpy(niov, iov, sizeof(struct iovec) * n); + + ALLOCA_CODE_FUNC(f, func); + + IOVEC_SET_STRING(niov[n++], file); + IOVEC_SET_STRING(niov[n++], line); + IOVEC_SET_STRING(niov[n++], f); + + return sd_journal_sendv(niov, n); +} + +_public_ int sd_journal_perror_with_location( + const char *file, const char *line, + const char *func, + const char *message) { + + struct iovec iov[6]; + char *f; + + ALLOCA_CODE_FUNC(f, func); + + IOVEC_SET_STRING(iov[0], file); + IOVEC_SET_STRING(iov[1], line); + IOVEC_SET_STRING(iov[2], f); + + return fill_iovec_perror_and_send(message, 3, iov); +} |