virt-aa-helper.c 31.4 KB
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/*
 * virt-aa-helper: wrapper program used by AppArmor security driver.
 * Copyright (C) 2009 Canonical Ltd.
 *
 * See COPYING.LIB for the License of this software
 *
 * Author:
 *   Jamie Strandboge <jamie@canonical.com>
 *
 */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
#include <getopt.h>
#include <stdbool.h>
#include <sys/utsname.h>

#include "internal.h"
#include "buf.h"
#include "util.h"
#include "memory.h"

#include "security_driver.h"
#include "security_apparmor.h"
#include "domain_conf.h"
#include "xml.h"
#include "uuid.h"
#include "hostusb.h"
#include "pci.h"

static char *progname;

typedef struct {
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    bool allowDiskFormatProbing;
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    char uuid[PROFILE_NAME_SIZE];       /* UUID of vm */
    bool dryrun;                /* dry run */
    char cmd;                   /* 'c'   create
                                 * 'a'   add (load)
                                 * 'r'   replace
                                 * 'R'   remove */
    char *files;                /* list of files */
    virDomainDefPtr def;        /* VM definition */
    virCapsPtr caps;            /* VM capabilities */
    char *hvm;                  /* type of hypervisor (eg hvm, xen) */
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    char *arch;                 /* machine architecture */
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    int bits;                   /* bits in the guest */
    char *newdisk;              /* newly added disk */
} vahControl;

static int
vahDeinit(vahControl * ctl)
{
    if (ctl == NULL)
        return -1;

    VIR_FREE(ctl->def);
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    virCapabilitiesFree(ctl->caps);
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    VIR_FREE(ctl->files);
    VIR_FREE(ctl->hvm);
    VIR_FREE(ctl->arch);
    VIR_FREE(ctl->newdisk);
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    return 0;
}

/*
 * Print usage
 */
static void
vah_usage(void)
{
    fprintf(stdout, "\n%s [options] [< def.xml]\n\n"
            "  Options:\n"
            "    -a | --add                     load profile\n"
            "    -c | --create                  create profile from template\n"
            "    -D | --delete                  unload and delete profile\n"
            "    -r | --replace                 reload profile\n"
            "    -R | --remove                  unload profile\n"
            "    -h | --help                    this help\n"
            "    -u | --uuid <uuid>             uuid (profile name)\n"
            "\n", progname);

    fprintf(stdout, "This command is intended to be used by libvirtd "
            "and not used directly.\n");
    return;
}

static void
vah_error(vahControl * ctl, int doexit, const char *str)
{
    fprintf(stderr, _("%s: error: %s\n"), progname, str);

    if (doexit) {
        if (ctl != NULL)
            vahDeinit(ctl);
        exit(EXIT_FAILURE);
    }
}

static void
vah_warning(const char *str)
{
    fprintf(stderr, _("%s: warning: %s\n"), progname, str);
}

static void
vah_info(const char *str)
{
    fprintf(stderr, _("%s:\n%s\n"), progname, str);
}

/*
 * Replace @oldstr in @orig with @repstr
 * @len is number of bytes allocated for @orig. Assumes @orig, @oldstr and
 * @repstr are null terminated
 */
static int
replace_string(char *orig, const size_t len, const char *oldstr,
               const char *repstr)
{
    int idx;
    char *pos = NULL;
    char *tmp = NULL;

    if ((pos = strstr(orig, oldstr)) == NULL) {
        vah_error(NULL, 0, "could not find replacement string");
        return -1;
    }

    if (VIR_ALLOC_N(tmp, len) < 0) {
        vah_error(NULL, 0, "could not allocate memory for string");
        return -1;
    }
    tmp[0] = '\0';

    idx = abs(pos - orig);

    /* copy everything up to oldstr */
    strncat(tmp, orig, idx);

    /* add the replacement string */
    if (strlen(tmp) + strlen(repstr) > len - 1) {
        vah_error(NULL, 0, "not enough space in target buffer");
        VIR_FREE(tmp);
        return -1;
    }
    strcat(tmp, repstr);

    /* add everything after oldstr */
    if (strlen(tmp) + strlen(orig) - (idx + strlen(oldstr)) > len - 1) {
        vah_error(NULL, 0, "not enough space in target buffer");
        VIR_FREE(tmp);
        return -1;
    }
    strncat(tmp, orig + idx + strlen(oldstr),
            strlen(orig) - (idx + strlen(oldstr)));

    if (virStrcpy(orig, tmp, len) == NULL) {
        vah_error(NULL, 0, "error replacing string");
        VIR_FREE(tmp);
        return -1;
    }
    VIR_FREE(tmp);

    return 0;
}

/*
 * run an apparmor_parser command
 */
static int
parserCommand(const char *profile_name, const char cmd)
{
    char flag[3];
    char profile[PATH_MAX];
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    int status;
    int ret;
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    if (strchr("arR", cmd) == NULL) {
        vah_error(NULL, 0, "invalid flag");
        return -1;
    }

    snprintf(flag, 3, "-%c", cmd);

    if (snprintf(profile, PATH_MAX, "%s/%s",
                 APPARMOR_DIR "/libvirt", profile_name) > PATH_MAX - 1) {
        vah_error(NULL, 0, "profile name exceeds maximum length");
        return -1;
    }

    if (!virFileExists(profile)) {
        vah_error(NULL, 0, "profile does not exist");
        return -1;
    } else {
        const char * const argv[] = {
            "/sbin/apparmor_parser", flag, profile, NULL
        };
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        if ((ret = virRun(argv, &status)) != 0 ||
            (WIFEXITED(status) && WEXITSTATUS(status) != 0)) {
            if (ret != 0) {
                vah_error(NULL, 0, "failed to run apparmor_parser");
                return -1;
            } else if (cmd == 'R' && WIFEXITED(status) && WEXITSTATUS(status) == 234) {
                vah_warning("unable to unload already unloaded profile (non-fatal)");
            } else {
                vah_error(NULL, 0, "apparmor_parser exited with error");
                return -1;
            }
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        }
    }

    return 0;
}

/*
 * Update the dynamic files
 */
static int
update_include_file(const char *include_file, const char *included_files)
{
    int rc = -1;
    int plen;
    int fd;
    char *pcontent = NULL;
    const char *warning =
         "# DO NOT EDIT THIS FILE DIRECTLY. IT IS MANAGED BY LIBVIRT.\n";

    if (virAsprintf(&pcontent, "%s%s", warning, included_files) == -1) {
        vah_error(NULL, 0, "could not allocate memory for profile");
        return rc;
    }

    plen = strlen(pcontent);
    if (plen > MAX_FILE_LEN) {
        vah_error(NULL, 0, "invalid length for new profile");
        goto clean;
    }

    /* only update the disk profile if it is different */
    if (virFileExists(include_file)) {
        char *existing = NULL;
        int flen = virFileReadAll(include_file, MAX_FILE_LEN, &existing);
        if (flen < 0)
            goto clean;

        if (flen == plen) {
            if (STREQLEN(existing, pcontent, plen)) {
                rc = 0;
                VIR_FREE(existing);
                goto clean;
            }
        }
        VIR_FREE(existing);
    }

    /* write the file */
    if ((fd = open(include_file, O_CREAT | O_TRUNC | O_WRONLY, 0644)) == -1) {
        vah_error(NULL, 0, "failed to create include file");
        goto clean;
    }

    if (safewrite(fd, pcontent, plen) < 0) { /* don't write the '\0' */
        close(fd);
        vah_error(NULL, 0, "failed to write to profile");
        goto clean;
    }

    if (close(fd) != 0) {
        vah_error(NULL, 0, "failed to close or write to profile");
        goto clean;
    }
    rc = 0;

  clean:
    VIR_FREE(pcontent);

    return rc;
}

/*
 * Create a profile based on a template
 */
static int
create_profile(const char *profile, const char *profile_name,
               const char *profile_files)
{
    char template[PATH_MAX];
    char *tcontent = NULL;
    char *pcontent = NULL;
    char *replace_name = NULL;
    char *replace_files = NULL;
    const char *template_name = "\nprofile LIBVIRT_TEMPLATE";
    const char *template_end = "\n}";
    int tlen, plen;
    int fd;
    int rc = -1;

    if (virFileExists(profile)) {
        vah_error(NULL, 0, "profile exists");
        goto end;
    }

    if (snprintf(template, PATH_MAX, "%s/TEMPLATE",
                 APPARMOR_DIR "/libvirt") > PATH_MAX - 1) {
        vah_error(NULL, 0, "template name exceeds maximum length");
        goto end;
    }

    if (!virFileExists(template)) {
        vah_error(NULL, 0, "template does not exist");
        goto end;
    }

    if ((tlen = virFileReadAll(template, MAX_FILE_LEN, &tcontent)) < 0) {
        vah_error(NULL, 0, "failed to read AppArmor template");
        goto end;
    }

    if (strstr(tcontent, template_name) == NULL) {
        vah_error(NULL, 0, "no replacement string in template");
        goto clean_tcontent;
    }

    if (strstr(tcontent, template_end) == NULL) {
        vah_error(NULL, 0, "no replacement string in template");
        goto clean_tcontent;
    }

    /* '\nprofile <profile_name>\0' */
    if (virAsprintf(&replace_name, "\nprofile %s", profile_name) == -1) {
        vah_error(NULL, 0, "could not allocate memory for profile name");
        goto clean_tcontent;
    }

    /* '\n<profile_files>\n}\0' */
    if (virAsprintf(&replace_files, "\n%s\n}", profile_files) == -1) {
        vah_error(NULL, 0, "could not allocate memory for profile files");
        VIR_FREE(replace_name);
        goto clean_tcontent;
    }

    plen = tlen + strlen(replace_name) - strlen(template_name) +
           strlen(replace_files) - strlen(template_end) + 1;
    if (plen > MAX_FILE_LEN || plen < tlen) {
        vah_error(NULL, 0, "invalid length for new profile");
        goto clean_replace;
    }

    if (VIR_ALLOC_N(pcontent, plen) < 0) {
        vah_error(NULL, 0, "could not allocate memory for profile");
        goto clean_replace;
    }
    pcontent[0] = '\0';
    strcpy(pcontent, tcontent);

    if (replace_string(pcontent, plen, template_name, replace_name) < 0)
        goto clean_all;

    if (replace_string(pcontent, plen, template_end, replace_files) < 0)
        goto clean_all;

    /* write the file */
    if ((fd = open(profile, O_CREAT | O_EXCL | O_WRONLY, 0644)) == -1) {
        vah_error(NULL, 0, "failed to create profile");
        goto clean_all;
    }

    if (safewrite(fd, pcontent, plen - 1) < 0) { /* don't write the '\0' */
        close(fd);
        vah_error(NULL, 0, "failed to write to profile");
        goto clean_all;
    }

    if (close(fd) != 0) {
        vah_error(NULL, 0, "failed to close or write to profile");
        goto clean_all;
    }
    rc = 0;

  clean_all:
    VIR_FREE(pcontent);
  clean_replace:
    VIR_FREE(replace_name);
    VIR_FREE(replace_files);
  clean_tcontent:
    VIR_FREE(tcontent);
  end:
    return rc;
}

/*
 * Load an existing profile
 */
static int
parserLoad(const char *profile_name)
{
    return parserCommand(profile_name, 'a');
}

/*
 * Remove an existing profile
 */
static int
parserRemove(const char *profile_name)
{
    return parserCommand(profile_name, 'R');
}

/*
 * Replace an existing profile
 */
static int
parserReplace(const char *profile_name)
{
    return parserCommand(profile_name, 'r');
}

static int
valid_uuid(const char *uuid)
{
    unsigned char rawuuid[VIR_UUID_BUFLEN];

    if (strlen(uuid) != PROFILE_NAME_SIZE - 1)
        return -1;

    if (!STRPREFIX(uuid, AA_PREFIX))
        return -1;

    if (virUUIDParse(uuid + strlen(AA_PREFIX), rawuuid) < 0)
        return -1;

    return 0;
}

static int
valid_name(const char *name)
{
    /* just try to filter out any dangerous characters in the name that can be
     * used to subvert the profile */
    const char *bad = " /[]*";

    if (strlen(name) == 0 || strlen(name) > PATH_MAX - 1)
        return -1;

    if (strcspn(name, bad) != strlen(name))
        return -1;

    return 0;
}

/* see if one of the strings in arr starts with str */
static int
array_starts_with(const char *str, const char * const *arr, const long size)
{
    int i;
    for (i = 0; i < size; i++) {
        if (strlen(str) < strlen(arr[i]))
            continue;

        if (STRPREFIX(str, arr[i]))
            return 0;
    }
    return 1;
}

/*
 * Don't allow access to special files or restricted paths such as /bin, /sbin,
 * /usr/bin, /usr/sbin and /etc. This is in an effort to prevent read/write
 * access to system files which could be used to elevate privileges. This is a
 * safety measure in case libvirtd is under a restrictive profile and is
 * subverted and trying to escape confinement.
 *
 * Note that we cannot exclude block devices because they are valid devices.
 * The TEMPLATE file can be adjusted to explicitly disallow these if needed.
 *
 * RETURN: -1 on error, 0 if ok, 1 if blocked
 */
static int
valid_path(const char *path, const bool readonly)
{
    struct stat sb;
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    int npaths, opaths;
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    const char * const restricted[] = {
        "/bin/",
        "/etc/",
        "/lib",
        "/lost+found/",
        "/proc/",
        "/sbin/",
        "/selinux/",
        "/sys/",
        "/usr/bin/",
        "/usr/lib",
        "/usr/sbin/",
        "/usr/share/",
        "/usr/local/bin/",
        "/usr/local/etc/",
        "/usr/local/lib",
        "/usr/local/sbin/"
    };
    /* these paths are ok for readonly, but not read/write */
    const char * const restricted_rw[] = {
        "/boot/",
        "/vmlinuz",
        "/initrd",
        "/initrd.img"
    };
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    /* override the above with these */
    const char * const override[] = {
        "/sys/devices/pci"	/* for hostdev pci devices */
    };
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    if (path == NULL || strlen(path) > PATH_MAX - 1) {
        vah_error(NULL, 0, "bad pathname");
        return -1;
    }

    /* Don't allow double quotes, since we use them to quote the filename
     * and this will confuse the apparmor parser.
     */
    if (strchr(path, '"') != NULL)
        return 1;

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    /* Require an absolute path */
    if (STRNEQLEN(path, "/", 1))
        return 1;

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    if (!virFileExists(path))
        vah_warning("path does not exist, skipping file type checks");
    else {
        if (stat(path, &sb) == -1)
            return -1;

        switch (sb.st_mode & S_IFMT) {
            case S_IFDIR:
                return 1;
                break;
            case S_IFIFO:
                return 1;
                break;
            case S_IFSOCK:
                return 1;
                break;
            default:
                break;
        }
    }

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    opaths = sizeof(override)/sizeof *(override);

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    npaths = sizeof(restricted)/sizeof *(restricted);
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    if (array_starts_with(path, restricted, npaths) == 0 &&
        array_starts_with(path, override, opaths) != 0)
            return 1;
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    npaths = sizeof(restricted_rw)/sizeof *(restricted_rw);
    if (!readonly) {
        if (array_starts_with(path, restricted_rw, npaths) == 0)
            return 1;
    }

    return 0;
}

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/* Called from SAX on parsing errors in the XML. */
static void
catchXMLError (void *ctx, const char *msg ATTRIBUTE_UNUSED, ...)
{
    xmlParserCtxtPtr ctxt = (xmlParserCtxtPtr) ctx;

    if (ctxt) {
        if (virGetLastError() == NULL &&
            ctxt->lastError.level == XML_ERR_FATAL &&
            ctxt->lastError.message != NULL) {
                char *err_str = NULL;
                if (virAsprintf(&err_str, "XML error at line %d: %s",
                                ctxt->lastError.line,
                                ctxt->lastError.message) == -1)
                    vah_error(NULL, 0, "Could not get XML error");
                else {
                    vah_error(NULL, 0, err_str);
                    VIR_FREE(err_str);
                }
        }
    }
}

/*
 * Parse the xml we received to fill in the following:
 * ctl->hvm
 * ctl->arch
 * ctl->bits
 *
 * These are suitable for setting up a virCapsPtr
 */
static int
caps_mockup(vahControl * ctl, const char *xmlStr)
{
    int rc = -1;
    xmlParserCtxtPtr pctxt = NULL;
    xmlDocPtr xml = NULL;
    xmlXPathContextPtr ctxt = NULL;
    xmlNodePtr root;

    /* Set up a parser context so we can catch the details of XML errors. */
    pctxt = xmlNewParserCtxt ();
    if (!pctxt || !pctxt->sax)
        goto cleanup;
    pctxt->sax->error = catchXMLError;

    xml = xmlCtxtReadDoc (pctxt, BAD_CAST xmlStr, "domain.xml", NULL,
                          XML_PARSE_NOENT | XML_PARSE_NONET |
                          XML_PARSE_NOWARNING);
    if (!xml) {
        if (virGetLastError() == NULL)
            vah_error(NULL, 0, "failed to parse xml document");
        goto cleanup;
    }

    if ((root = xmlDocGetRootElement(xml)) == NULL) {
        vah_error(NULL, 0, "missing root element");
        goto cleanup;
    }

    if (!xmlStrEqual(root->name, BAD_CAST "domain")) {
        vah_error(NULL, 0, "incorrect root element");
        goto cleanup;
    }

    if ((ctxt = xmlXPathNewContext(xml)) == NULL) {
        vah_error(ctl, 0, "could not allocate memory");
        goto cleanup;
    }
    ctxt->node = root;

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    ctl->hvm = virXPathString("string(./os/type[1])", ctxt);
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    if (!ctl->hvm || STRNEQ(ctl->hvm, "hvm")) {
        vah_error(ctl, 0, "os.type is not 'hvm'");
        goto cleanup;
    }
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    ctl->arch = virXPathString("string(./os/type[1]/@arch)", ctxt);
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    if (!ctl->arch) {
        /* The XML we are given should have an arch, but in case it doesn't,
         * just use the host's arch.
         */
        struct utsname utsname;

        /* Really, this never fails - look at the man-page. */
        uname (&utsname);
        if ((ctl->arch = strdup(utsname.machine)) == NULL) {
            vah_error(ctl, 0, "could not allocate memory");
            goto cleanup;
        }
    }
    if (STREQ(ctl->arch, "x86_64"))
        ctl->bits = 64;
    else
        ctl->bits = 32;

    rc = 0;

  cleanup:
    xmlFreeParserCtxt (pctxt);
    xmlFreeDoc (xml);
    xmlXPathFreeContext(ctxt);

    return rc;
}

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static int
get_definition(vahControl * ctl, const char *xmlStr)
{
    int rc = -1;
    virCapsGuestPtr guest;  /* this is freed when caps is freed */

    /*
     * mock up some capabilities. We don't currently use these explicitly,
     * but need them for virDomainDefParseString().
     */
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    if (caps_mockup(ctl, xmlStr) != 0)
        goto exit;
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    if ((ctl->caps = virCapabilitiesNew(ctl->arch, 1, 1)) == NULL) {
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        vah_error(ctl, 0, "could not allocate memory");
        goto exit;
    }

    if ((guest = virCapabilitiesAddGuest(ctl->caps,
                                         ctl->hvm,
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                                         ctl->arch,
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                                         ctl->bits,
                                         NULL,
                                         NULL,
                                         0,
                                         NULL)) == NULL) {
        vah_error(ctl, 0, "could not allocate memory");
        goto exit;
    }

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    ctl->def = virDomainDefParseString(ctl->caps, xmlStr,
                                       VIR_DOMAIN_XML_INACTIVE);
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    if (ctl->def == NULL) {
        vah_error(ctl, 0, "could not parse XML");
        goto exit;
    }

    if (!ctl->def->name) {
        vah_error(ctl, 0, "could not find name in XML");
        goto exit;
    }

    if (valid_name(ctl->def->name) != 0) {
        vah_error(ctl, 0, "bad name");
        goto exit;
    }

    rc = 0;

  exit:
    return rc;
}

static int
vah_add_file(virBufferPtr buf, const char *path, const char *perms)
{
    char *tmp = NULL;
    int rc = -1;
    bool readonly = true;

    if (path == NULL)
        return rc;

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    /* Skip files without an absolute path. Not having one confuses the
     * apparmor parser and this also ensures things like tcp consoles don't
     * get added to the profile.
     */
    if (STRNEQLEN(path, "/", 1)) {
        vah_warning(path);
        vah_warning("  skipped non-absolute path");
        return 0;
    }

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    if (virFileExists(path)) {
        if ((tmp = realpath(path, NULL)) == NULL) {
            vah_error(NULL, 0, path);
            vah_error(NULL, 0, "  could not find realpath for disk");
            return rc;
        }
    } else
        if ((tmp = strdup(path)) == NULL)
            return rc;

    if (strchr(perms, 'w') != NULL)
        readonly = false;

    rc = valid_path(tmp, readonly);
    if (rc != 0) {
        if (rc > 0) {
            vah_error(NULL, 0, path);
            vah_error(NULL, 0, "  skipped restricted file");
        }
        goto clean;
    }

    virBufferVSprintf(buf, "  \"%s\" %s,\n", tmp, perms);
777
    if (readonly) {
778
        virBufferVSprintf(buf, "  # don't audit writes to readonly files\n");
779 780
        virBufferVSprintf(buf, "  deny \"%s\" w,\n", tmp);
    }
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  clean:
783
    VIR_FREE(tmp);
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    return rc;
}

static int
789 790 791 792 793 794 795 796 797 798
file_iterate_hostdev_cb(usbDevice *dev ATTRIBUTE_UNUSED,
                        const char *file, void *opaque)
{
    virBufferPtr buf = opaque;
    return vah_add_file(buf, file, "rw");
}

static int
file_iterate_pci_cb(pciDevice *dev ATTRIBUTE_UNUSED,
                        const char *file, void *opaque)
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{
    virBufferPtr buf = opaque;
    return vah_add_file(buf, file, "rw");
}

804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821
static int
add_file_path(virDomainDiskDefPtr disk,
              const char *path,
              size_t depth,
              void *opaque)
{
    virBufferPtr buf = opaque;
    int ret;

    if (depth == 0) {
        if (disk->readonly)
            ret = vah_add_file(buf, path, "r");
        else
            ret = vah_add_file(buf, path, "rw");
    } else {
        ret = vah_add_file(buf, path, "r");
    }

822 823 824
    if (ret != 0)
        ret = -1;

825 826 827 828
    return ret;
}


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static int
get_files(vahControl * ctl)
{
    virBuffer buf = VIR_BUFFER_INITIALIZER;
    int rc = -1;
    int i;
    char *uuid;
    char uuidstr[VIR_UUID_STRING_BUFLEN];

    /* verify uuid is same as what we were given on the command line */
    virUUIDFormat(ctl->def->uuid, uuidstr);
    if (virAsprintf(&uuid, "%s%s", AA_PREFIX, uuidstr) == -1) {
        vah_error(ctl, 0, "could not allocate memory");
        return rc;
    }

    if (STRNEQ(uuid, ctl->uuid)) {
        vah_error(ctl, 0, "given uuid does not match XML uuid");
        goto clean;
    }

850
    for (i = 0; i < ctl->def->ndisks; i++) {
851 852 853 854
        /* XXX passing ignoreOpenFailure = true to get back to the behavior
         * from before using virDomainDiskDefForeachPath. actually we should
         * be passing ignoreOpenFailure = false and handle open errors more
         * careful than just ignoring them */
855
        int ret = virDomainDiskDefForeachPath(ctl->def->disks[i],
856
                                              ctl->allowDiskFormatProbing,
857
                                              true,
858 859 860 861 862
                                              add_file_path,
                                              &buf);
        if (ret != 0)
            goto clean;
    }
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    for (i = 0; i < ctl->def->nserials; i++)
        if (ctl->def->serials[i] && ctl->def->serials[i]->data.file.path)
            if (vah_add_file(&buf,
                             ctl->def->serials[i]->data.file.path, "w") != 0)
                goto clean;

    if (ctl->def->console && ctl->def->console->data.file.path)
        if (vah_add_file(&buf, ctl->def->console->data.file.path, "w") != 0)
            goto clean;

874
    if (ctl->def->os.kernel)
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        if (vah_add_file(&buf, ctl->def->os.kernel, "r") != 0)
            goto clean;

878
    if (ctl->def->os.initrd)
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        if (vah_add_file(&buf, ctl->def->os.initrd, "r") != 0)
            goto clean;

    if (ctl->def->os.loader && ctl->def->os.loader)
        if (vah_add_file(&buf, ctl->def->os.loader, "r") != 0)
884 885 886 887 888 889
            goto clean;

    if (ctl->def->ngraphics == 1 &&
        ctl->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SDL)
        if (vah_add_file(&buf, ctl->def->graphics[0]->data.sdl.xauth,
                         "r") != 0)
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            goto clean;

    for (i = 0; i < ctl->def->nhostdevs; i++)
        if (ctl->def->hostdevs[i]) {
            virDomainHostdevDefPtr dev = ctl->def->hostdevs[i];
            switch (dev->source.subsys.type) {
            case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_USB: {
897
                usbDevice *usb = usbGetDevice(dev->source.subsys.u.usb.bus,
898
                                              dev->source.subsys.u.usb.device);
899 900 901 902

                if (usb == NULL)
                    continue;

903
                rc = usbDeviceFileIterate(usb, file_iterate_hostdev_cb, &buf);
904
                usbFreeDevice(usb);
905 906
                if (rc != 0)
                    goto clean;
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                break;
            }
909

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            case VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI: {
911
                pciDevice *pci = pciGetDevice(
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                           dev->source.subsys.u.pci.domain,
                           dev->source.subsys.u.pci.bus,
                           dev->source.subsys.u.pci.slot,
                           dev->source.subsys.u.pci.function);

                if (pci == NULL)
                    continue;

920
                rc = pciDeviceFileIterate(pci, file_iterate_pci_cb, &buf);
921
                pciFreeDevice(pci);
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                break;
            }
925

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            default:
                rc = 0;
                break;
            } /* switch */
        }

    if (ctl->newdisk)
        if (vah_add_file(&buf, ctl->newdisk, "rw") != 0)
            goto clean;

    if (virBufferError(&buf)) {
937 938 939
        virBufferFreeAndReset(&buf);
        vah_error(NULL, 0, "failed to allocate file buffer");
        goto clean;
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    }

    rc = 0;
    ctl->files = virBufferContentAndReset(&buf);

  clean:
    VIR_FREE(uuid);
    return rc;
}

static int
vahParseArgv(vahControl * ctl, int argc, char **argv)
{
    int arg, idx = 0;
    struct option opt[] = {
955
        {"probing", 1, 0, 'p' },
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        {"add", 0, 0, 'a'},
        {"create", 0, 0, 'c'},
        {"dryrun", 0, 0, 'd'},
        {"delete", 0, 0, 'D'},
        {"add-file", 0, 0, 'f'},
        {"help", 0, 0, 'h'},
        {"replace", 0, 0, 'r'},
        {"remove", 0, 0, 'R'},
        {"uuid", 1, 0, 'u'},
        {0, 0, 0, 0}
    };

968
    while ((arg = getopt_long(argc, argv, "acdDhrRH:b:u:p:f:", opt,
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            &idx)) != -1) {
        switch (arg) {
            case 'a':
                ctl->cmd = 'a';
                break;
            case 'c':
                ctl->cmd = 'c';
                break;
            case 'd':
                ctl->dryrun = true;
                break;
            case 'D':
                ctl->cmd = 'D';
                break;
            case 'f':
                if ((ctl->newdisk = strdup(optarg)) == NULL)
                    vah_error(ctl, 1, "could not allocate memory for disk");
                break;
            case 'h':
                vah_usage();
                exit(EXIT_SUCCESS);
                break;
            case 'r':
                ctl->cmd = 'r';
                break;
            case 'R':
                ctl->cmd = 'R';
                break;
            case 'u':
                if (strlen(optarg) > PROFILE_NAME_SIZE - 1)
                    vah_error(ctl, 1, "invalid UUID");
                if (virStrcpy((char *) ctl->uuid, optarg,
                    PROFILE_NAME_SIZE) == NULL)
                    vah_error(ctl, 1, "error copying UUID");
                break;
1004 1005 1006 1007 1008 1009
            case 'p':
                if (STREQ(optarg, "1"))
                    ctl->allowDiskFormatProbing = true;
                else
                    ctl->allowDiskFormatProbing = false;
                break;
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1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
            default:
                vah_error(ctl, 1, "unsupported option");
                break;
        }
    }
    if (strchr("acDrR", ctl->cmd) == NULL)
        vah_error(ctl, 1, "bad command");

    if (valid_uuid(ctl->uuid) != 0)
        vah_error(ctl, 1, "invalid UUID");

    if (!ctl->cmd) {
        vah_usage();
        exit(EXIT_FAILURE);
    }

    if (ctl->cmd == 'c' || ctl->cmd == 'r') {
        char *xmlStr = NULL;
        if (virFileReadLimFD(STDIN_FILENO, MAX_FILE_LEN, &xmlStr) < 0)
            vah_error(ctl, 1, "could not read xml file");

        if (get_definition(ctl, xmlStr) != 0 || ctl->def == NULL) {
            VIR_FREE(xmlStr);
            vah_error(ctl, 1, "could not get VM definition");
        }
        VIR_FREE(xmlStr);

        if (get_files(ctl) != 0)
            vah_error(ctl, 1, "invalid VM definition");
    }
    return 0;
}


/*
 * virt-aa-helper -c -u UUID < file.xml
 * virt-aa-helper -r -u UUID [-f <file>] < file.xml
 * virt-aa-helper -a -u UUID
 * virt-aa-helper -R -u UUID
 * virt-aa-helper -D -u UUID
 */
int
main(int argc, char **argv)
{
    vahControl _ctl, *ctl = &_ctl;
    virBuffer buf = VIR_BUFFER_INITIALIZER;
    int rc = -1;
    char profile[PATH_MAX];
    char include_file[PATH_MAX];

    /* clear the environment */
    environ = NULL;
    if (setenv("PATH", "/sbin:/usr/sbin", 1) != 0) {
        vah_error(ctl, 1, "could not set PATH");
    }
    if (setenv("IFS", " \t\n", 1) != 0) {
        vah_error(ctl, 1, "could not set IFS");
    }

    if (!(progname = strrchr(argv[0], '/')))
        progname = argv[0];
    else
        progname++;

    memset(ctl, 0, sizeof(vahControl));

    if (vahParseArgv(ctl, argc, argv) != 0)
        vah_error(ctl, 1, "could not parse arguments");

    if (snprintf(profile, PATH_MAX, "%s/%s",
                 APPARMOR_DIR "/libvirt", ctl->uuid) > PATH_MAX - 1)
        vah_error(ctl, 1, "profile name exceeds maximum length");

    if (snprintf(include_file, PATH_MAX, "%s/%s.files",
                 APPARMOR_DIR "/libvirt", ctl->uuid) > PATH_MAX - 1)
        vah_error(ctl, 1, "disk profile name exceeds maximum length");

    if (ctl->cmd == 'a')
        rc = parserLoad(ctl->uuid);
    else if (ctl->cmd == 'R' || ctl->cmd == 'D') {
        rc = parserRemove(ctl->uuid);
        if (ctl->cmd == 'D') {
            unlink(include_file);
            unlink(profile);
        }
    } else if (ctl->cmd == 'c' || ctl->cmd == 'r') {
        char *included_files = NULL;

        if (ctl->cmd == 'c' && virFileExists(profile))
            vah_error(ctl, 1, "profile exists");

        virBufferVSprintf(&buf, "  \"%s/log/libvirt/**/%s.log\" w,\n",
                          LOCAL_STATE_DIR, ctl->def->name);
        virBufferVSprintf(&buf, "  \"%s/lib/libvirt/**/%s.monitor\" rw,\n",
                          LOCAL_STATE_DIR, ctl->def->name);
        virBufferVSprintf(&buf, "  \"%s/run/libvirt/**/%s.pid\" rwk,\n",
                          LOCAL_STATE_DIR, ctl->def->name);
        if (ctl->files)
            virBufferVSprintf(&buf, "%s", ctl->files);

1110 1111
        if (virBufferError(&buf)) {
            virBufferFreeAndReset(&buf);
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Jamie Strandboge 已提交
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            vah_error(ctl, 1, "failed to allocate buffer");
1113
        }
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1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167

        included_files = virBufferContentAndReset(&buf);

        /* (re)create the include file using included_files */
        if (ctl->dryrun) {
            vah_info(include_file);
            vah_info(included_files);
            rc = 0;
        } else if ((rc = update_include_file(include_file,
                                             included_files)) != 0)
            goto clean;


        /* create the profile from TEMPLATE */
        if (ctl->cmd == 'c') {
            char *tmp = NULL;
            if (virAsprintf(&tmp, "  #include <libvirt/%s.files>\n",
                            ctl->uuid) == -1) {
                vah_error(ctl, 0, "could not allocate memory");
                goto clean;
            }

            if (ctl->dryrun) {
                vah_info(profile);
                vah_info(ctl->uuid);
                vah_info(tmp);
                rc = 0;
            } else if ((rc = create_profile(profile, ctl->uuid, tmp)) != 0) {
                vah_error(ctl, 0, "could not create profile");
                unlink(include_file);
            }
            VIR_FREE(tmp);
        }

        if (rc == 0 && !ctl->dryrun) {
            if (ctl->cmd == 'c')
                rc = parserLoad(ctl->uuid);
            else
                rc = parserReplace(ctl->uuid);

            /* cleanup */
            if (rc != 0) {
                unlink(include_file);
                if (ctl->cmd == 'c')
                    unlink(profile);
            }
        }
      clean:
        VIR_FREE(included_files);
    }

    vahDeinit(ctl);
    exit(rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
}