[systemd-devel] [PATCH 6/6] Add SHA1 hash sum to coredump report

[Oleksii Shevchuk]

If coredump goes to raw file, compute hash sum of it and store to
journal. Feature is optional, if libgrcypt enabled (HAVE_GCRYPT)
---
 Makefile.am                   |  9 ++++++++
 src/journal/coredump.c        | 48 +++++++++++++++++++++++++++++++++++++++++++
 src/journal/journald-server.h |  2 +-
 3 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/Makefile.am b/Makefile.am
index af9e903..42cf7c6 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2672,6 +2672,15 @@ systemd_coredump_LDADD += \
 	libsystemd-login-internal.la
 endif
 
+if HAVE_GCRYPT
+systemd_coredump_CFLAGS = \
+	$(GCRYPT_CFLAGS) \
+	-Wno-pointer-arith
+
+systemd_coredump_LDADD += \
+	$(GCRYPT_LIBS)
+endif
+
 rootlibexec_PROGRAMS += \
 	systemd-coredump
 
diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index 680b26c..c9bda68 100644
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -24,6 +24,10 @@
 #include <stdio.h>
 #include <sys/prctl.h>
 
+#if defined(HAVE_GCRYPT)
+#include <gcrypt.h>
+#endif
+
 #include <systemd/sd-journal.h>
 
 #ifdef HAVE_LOGIND
@@ -50,6 +54,13 @@ enum {
         _ARG_MAX
 };
 
+#if defined(HAVE_GCRYPT)
+static void gcry_md_closep(gcry_md_hd_t *p)
+{
+        gcry_md_close(*p);
+}
+#endif
+
 static int submit_process_core(struct iovec iovec[15], int idx,
                                const char * comm,
                                const int journal)
@@ -61,6 +72,10 @@ static int submit_process_core(struct iovec iovec[15], int idx,
         _cleanup_free_   char * corelink = NULL;
         _cleanup_free_   char * t = NULL;
 
+#if defined(HAVE_GCRYPT)
+        _cleanup_free_   char * h = NULL;
+#endif
+
         if (journal) {
                 mkdir_p_label("/var/lib/systemd/coredump", 0755);
                 corelink = strdup("/var/lib/systemd/coredump/core.systemd-journald");
@@ -152,6 +167,17 @@ journal:
                         log_debug("chmod %s: %s", corepath, strerror(errno));
                 }
 
+#if defined(HAVE_GCRYPT)
+                __attribute__((cleanup(gcry_md_closep)))
+                        gcry_md_hd_t HD;
+                gcry_error_t gr = gcry_md_open (&HD, GCRY_MD_SHA1, 0);
+                if (gr != GPG_ERR_NO_ERROR) {
+                        log_error("Failed to initialize gcrypt hash context: %s",
+                                  gpg_strerror(gr));
+                        goto finish;
+                }
+#endif
+
                 for (;;) {
                         uint8_t buffer[4096];
                         size_t l, q;
@@ -171,6 +197,9 @@ journal:
                                 log_error("Failed to write coredump: %m");
                                 goto finish;
                         }
+#if defined(HAVE_GCRYPT)
+                        gcry_md_write(HD, buffer, l);
+#endif
                 }
 
                 fflush(corefile);
@@ -190,6 +219,25 @@ journal:
                 t = strjoin("COREDUMP_FILE=coredump/", corelink, NULL);
                 if (t)
                         IOVEC_SET_STRING(iovec[idx ++], t);
+
+#if defined(HAVE_GCRYPT)
+                char * bh = hexstr(gcry_md_read(HD, GCRY_MD_SHA1), 20);
+
+                if (! bh) {
+                        r = log_oom();
+                        goto finish;
+                }
+
+                h = strjoin("COREDUMP_FILE_SHA1=", bh, NULL);
+                free(bh);
+
+                if (! h) {
+                        r = log_oom();
+                        goto finish;
+                }
+
+                IOVEC_SET_STRING(iovec[idx ++], h);
+#endif
         }
 
         r = sd_journal_sendv(iovec, idx);
diff --git a/src/journal/journald-server.h b/src/journal/journald-server.h
index 9f50a29..3d05925 100644
--- a/src/journal/journald-server.h
+++ b/src/journal/journald-server.h
@@ -121,7 +121,7 @@ typedef struct Server {
         struct udev *udev;
 } Server;
 
-#define N_IOVEC_META_FIELDS 17
+#define N_IOVEC_META_FIELDS 18
 #define N_IOVEC_KERNEL_FIELDS 64
 #define N_IOVEC_UDEV_FIELDS 32
 
-- 
1.8.1.2