added basic backup of modified config files

2 files changed, 175 insertions, 11 deletions

diff --git a/worker/output_handler.c b/worker/output_handler.c
index f082a0f..c77e15c 100644
--- a/worker/output_handler.c
+++ b/worker/output_handler.c
@@ -4,6 +4,11 @@
 #include <unistd.h>
 #include <errno.h>
 #include <libgen.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+
 
 
 #include <libxml/tree.h>
@@ -21,6 +26,151 @@
 #include "xml_helper.h"
 #include "helpers.h"
 
+#define BACKUP_PATH "/var/spool/poliproc"
+#define ORIGINAL_BACKUP_EXTENSION "ipa_original_backup_DO_NOT_DELETE"
+
+static int copy_file(const char *src_name, const char *dest_name) {
+    int src_fd=-1;
+    int dest_fd=-1;
+    int ret=0;
+    struct stat stat_buffer;
+    void *src;
+    void *dest;
+    char *tmp_file_name=NULL;
+
+    tmp_file_name=(char *) malloc(strlen(src_name)+7);
+    CHECK(tmp_file_name, NULL, ("malloc failed."), return -1);
+    strcpy(tmp_file_name, src_name);
+    strcat(tmp_file_name, ".XXXXXX");
+
+    ret=-1;
+    src_fd = open(src_name, O_RDONLY);
+    CHECK(src_fd, -1, ("Failed to open %s read-only.\n", src_name), goto cleanup);
+
+    dest_fd=open_temporary_file(tmp_file_name, "0600", "root", "root", NULL);
+    CHECK(dest_fd, -1, ("Failed to open temporary file %s\n", tmp_file_name), goto cleanup);
+
+    ret=fstat(src_fd, &stat_buffer);
+    CHECK(ret, -1, ("Failed to stat file %s: %s\n", src_name, strerror(errno)), goto cleanup);
+
+    ret = lseek(dest_fd, stat_buffer.st_size - 1, SEEK_SET);
+    CHECK(ret, -1, ("Lseek failed for file %s: %s\n", dest_name, strerror(errno)), goto cleanup);
+
+    ret = write(dest_fd, "", 1);
+    if ( ret != 1 ) {
+        DEBUG(0, ("Failed to write one byte to %s: %s.\n", dest_name, strerror(errno)));
+        goto cleanup;
+    }
+    
+    src = mmap(NULL, stat_buffer.st_size, PROT_READ, MAP_SHARED, src_fd, 0);
+    if ( src == MAP_FAILED ) {
+        DEBUG(0, ("Mmap failed for file %s: %s.\n", src_name, strerror(errno)));
+        goto cleanup;
+    } 
+
+    dest = mmap(NULL, stat_buffer.st_size, PROT_READ | PROT_WRITE, MAP_SHARED,
+                dest_fd, 0);
+    if ( src == MAP_FAILED ) {
+        DEBUG(0, ("Mmap failed for file %s: %s.\n", src_name, strerror(errno)));
+        munmap(src, stat_buffer.st_size);
+        goto cleanup;
+    }
+
+    memcpy(dest, src, stat_buffer.st_size); 
+
+    munmap(dest, stat_buffer.st_size);
+    munmap(src, stat_buffer.st_size);
+
+    close(dest_fd);
+    close(src_fd);
+    ret=rename(tmp_file_name, dest_name);
+    CHECK(ret, -1, ("Cannot rename %s to %s: %s\n", tmp_file_name, dest_name, strerror(errno) ), goto cleanup);
+
+cleanup:
+    if (dest_fd != -1) close(dest_fd);
+    if (src_fd != -1) close(src_fd);
+    free(tmp_file_name);
+
+    return ret;
+}
+static int check_dir_create(const char *name) {
+    int ret;
+    struct stat stat_buffer;
+
+    if( (ret=stat(name, &stat_buffer)) == -1) {
+        DEBUG(0, ("Directory %s does not exist, creating it.\n", name, strerror(errno)));
+        ret=mkdir(name, 0600);
+        CHECK(ret, -1, ("mkdir %s failed: %s\n", name, strerror(errno)), return -1);
+    } else if (!S_ISDIR(stat_buffer.st_mode)) {
+        DEBUG(0,("%s is not a regular file!\n",name));
+        return -1;
+    } 
+
+    return 0;
+}
+
+static int safe_config_file(const char *name, const char *app_name) {
+    int ret;
+    struct stat stat_buffer;
+    char backup_dir[PATH_MAX];
+    char backup_file[PATH_MAX];
+    char original_backup[PATH_MAX];
+    char *buffer=NULL;
+    char *base_name=NULL;
+
+    if ( (ret=lstat(name, &stat_buffer)) == -1) {
+        DEBUG(0,("stat on %s failed: %s\n",name, strerror(errno)));
+        goto cleanup;
+    }
+    if (!S_ISREG(stat_buffer.st_mode)) {
+        DEBUG(0,("%s is not a regular file!\n",name));
+        ret=-1;
+        goto cleanup;
+    } 
+
+    ret=check_dir_create(BACKUP_PATH);
+    CHECK(ret, -1, ("Failed to create main backup directory %s.\n", BACKUP_PATH), goto cleanup);
+
+    ret=snprintf(backup_dir, PATH_MAX, "%s/%s", BACKUP_PATH, app_name);
+    ret=snprintf(original_backup, PATH_MAX, "%s/%s.%s",backup_dir,base_name,ORIGINAL_BACKUP_EXTENSION);
+    if (ret<0) {
+        DEBUG(0,("snprintf failed.\n"));
+        ret=-1;
+        goto cleanup;
+    }
+    ret=check_dir_create(backup_dir);
+    CHECK(ret, -1, ("Failed to create backup directory %s for application %s.\n", backup_dir, app_name), goto cleanup);
+
+    buffer=strdup(name);
+    base_name=basename(buffer);
+    ret=snprintf(original_backup, PATH_MAX, "%s/%s.%s",backup_dir,base_name,ORIGINAL_BACKUP_EXTENSION);
+    if (ret<0) {
+        DEBUG(0,("snprintf failed.\n"));
+        ret=-1;
+        goto cleanup;
+    }
+
+    if ( (ret=lstat(original_backup, &stat_buffer)) == -1) {
+        DEBUG(0, ("There is no original backup file, I will assume that %s is the original file.\n", name));
+        ret=copy_file(name, original_backup);
+    } else {
+        DEBUG(3, ("Original backup file exists, I will create an ordinary backup file\n", name));
+        ret=snprintf(backup_file, PATH_MAX, "%s/%s.%d",backup_dir,base_name,time(NULL));
+        if (ret<0) {
+            DEBUG(0,("snprintf failed.\n"));
+            ret=-1;
+            goto cleanup;
+        }
+        ret=copy_file(name, backup_file);
+    }
+
+
+cleanup:
+    free(buffer);
+    return ret;
+}
+
+
 char *get_output_handler_parameter(xmlNode *node, const char *name, const char *default_value, const int required) {
     char *value;
 
@@ -51,14 +201,15 @@ int output_handler_file(xmlNode *node, const xmlDocPtr doc, const char *xslt_fil
     char *permission=NULL;
     char *param_name=NULL;
     char *param_value=NULL;
+    char *app_name=NULL;
     struct stat stat_buffer;
     char *dir_name=NULL;
     char *tmp_file_name=NULL;
     char *buffer=NULL;
-    int ret;
+    int ret=0;
     int fd;
     xsltStylesheetPtr parsed_stylesheet = NULL;
-    xmlDocPtr res;
+    xmlDocPtr res=NULL;
 
     name=get_output_handler_parameter(node, "name", NULL, 1);
    
@@ -67,20 +218,22 @@ int output_handler_file(xmlNode *node, const xmlDocPtr doc, const char *xslt_fil
     dir_name=dirname(buffer); 
     if( (ret=stat(dir_name, &stat_buffer)) == -1) {
         DEBUG(0,("stat on %s failed: %s\n",dir_name, strerror(errno)));
-        goto failed;
+        goto cleanup;
     }
     if(!S_ISDIR(stat_buffer.st_mode)) {
         DEBUG(0,("%s is not a directory!\n",dir_name));
-        goto failed;
+        ret=-1;
+        goto cleanup;
     } 
 
     if( (ret=lstat(name, &stat_buffer)) == -1) {
         DEBUG(0,("stat on %s failed: %s\n",name, strerror(errno)));
-        goto failed;
+        goto cleanup;
     }
     if(!S_ISREG(stat_buffer.st_mode)) {
         DEBUG(0,("%s is not a regular file!\n",name));
-        goto failed;
+        ret=-1;
+        goto cleanup;
     } 
      
     owner=get_output_handler_parameter(node, "owner", "root", 0);
@@ -91,6 +244,11 @@ int output_handler_file(xmlNode *node, const xmlDocPtr doc, const char *xslt_fil
     param_value=get_output_handler_parameter(node, "param_value", NULL, 0);
 
     /* TODO: create backup copy */
+    app_name = find_by_xpath(doc, "//def:metadata/def:app", FIND_VALUE);
+    CHECK(app_name, NULL, ("Cannot find the name of the application in policy file.\n"), goto failed);
+    DEBUG(3, ("Found application name: %s\n", app_name));
+    ret=safe_config_file(name, app_name);
+    CHECK(ret, -1, ("Failed to safe config file %s of application %s.\n", name, app_name), goto cleanup);
 
     tmp_file_name=(char *) malloc(strlen(name)+7);
     CHECK_NULL_RETURN(tmp_file_name,("malloc failed."));
@@ -107,14 +265,17 @@ int output_handler_file(xmlNode *node, const xmlDocPtr doc, const char *xslt_fil
     ret = xsltSaveResultToFd(fd, res, parsed_stylesheet);
     if (ret == -1) {
         DEBUG(0, ("Cannot save result!\n"));
-        exit(1);
+        close(fd);
+        goto cleanup;
     }
-    xmlFreeDoc(res);
-    xsltFreeStylesheet(parsed_stylesheet);
 
     close(fd);
     ret=rename(tmp_file_name, name);
-    CHECK_MINUS_ONE_RETURN(ret, ("Cannot rename %s to %s: %s\n", tmp_file_name, name, strerror(errno) ));
+    CHECK(ret, -1, ("Cannot rename %s to %s: %s\n", tmp_file_name, name, strerror(errno) ), goto cleanup);
+
+cleanup:
+    xmlFreeDoc(res);
+    xsltFreeStylesheet(parsed_stylesheet);
 
     free(buffer);
     free(tmp_file_name);
@@ -125,7 +286,8 @@ int output_handler_file(xmlNode *node, const xmlDocPtr doc, const char *xslt_fil
     free(permission);
     free(param_name);
     free(param_value);
-    return 0;
+    free(app_name);
+    return ret;
 
 failed:
     free(buffer);
@@ -137,6 +299,7 @@ failed:
     free(permission);
     free(param_name);
     free(param_value);
+    free(app_name);
     return -1;
 }
 
diff --git a/worker/worker.c b/worker/worker.c
index 33b3afb..327f948 100644
--- a/worker/worker.c
+++ b/worker/worker.c
@@ -113,6 +113,7 @@ int main(int argc, const char *argv[])
 
 cleanup:
     free_xml_search_path();
+    free(policy_file_name);
 
     return ret;
 }