There's a lot of fixed buffers in use here. Clean up the code and
add more documentation on the different formats that have been
used by the kernel.
Signed-off-by: David Härdeman <david@xxxxxxxxxxx>
---
utils/gssd/gssd.c | 208 ++++++++++++++++++++++++++++-------------------------
1 file changed, 110 insertions(+), 98 deletions(-)
diff --git a/utils/gssd/gssd.c b/utils/gssd/gssd.c
index 91e3e05..78b836d 100644
--- a/utils/gssd/gssd.c
+++ b/utils/gssd/gssd.c
@@ -83,6 +83,9 @@ int root_uses_machine_creds = 1;
unsigned int context_timeout = 0;
unsigned int rpc_timeout = 5;
char *preferred_realm = NULL;
+/* Avoid DNS reverse lookups on server names */
+static bool avoid_dns = true;
+
TAILQ_HEAD(topdir_list_head, topdir) topdir_list;
@@ -120,9 +123,6 @@ struct topdir {
* and rescan the whole {rpc_pipefs} when this happens.
*/
-/* Avoid DNS reverse lookups on server names */
-static int avoid_dns = 1;
-
/*
* convert a presentation address string to a sockaddr_storage struct. Returns
* true on success or false on failure.
@@ -136,8 +136,8 @@ static int avoid_dns = 1;
* Microsoft "standard" of using the ipv6-literal.net domainname, but it's
* not really feasible at present.
*/
-static int
-addrstr_to_sockaddr(struct sockaddr *sa, const char *node, const char *port)
+static bool
+gssd_addrstr_to_sockaddr(struct sockaddr *sa, const char *node, const char *port)
{
int rc;
struct addrinfo *res;
@@ -150,9 +150,9 @@ addrstr_to_sockaddr(struct sockaddr *sa, const char *node, const char *port)
rc = getaddrinfo(node, port, &hints, &res);
if (rc) {
printerr(0, "ERROR: unable to convert %s|%s to sockaddr: %s\n",
- node, port, rc == EAI_SYSTEM ? strerror(errno) :
- gai_strerror(rc));
- return 0;
+ node, port,
+ rc == EAI_SYSTEM ? strerror(errno) : gai_strerror(rc));
+ return false;
}
#ifdef IPV6_SUPPORTED
@@ -167,46 +167,41 @@ addrstr_to_sockaddr(struct sockaddr *sa, const char *node, const char *port)
printerr(0, "ERROR: address %s has non-zero "
"sin6_scope_id!\n", node);
freeaddrinfo(res);
- return 0;
+ return false;
}
}
#endif /* IPV6_SUPPORTED */
memcpy(sa, res->ai_addr, res->ai_addrlen);
freeaddrinfo(res);
- return 1;
+ return true;
}
/*
* convert a sockaddr to a hostname
*/
static char *
-get_servername(const char *name, const struct sockaddr *sa, const char *addr)
+gssd_get_servername(const char *name, const struct sockaddr *sa, const char *addr)
{
socklen_t addrlen;
int err;
- char *hostname;
char hbuf[NI_MAXHOST];
unsigned char buf[sizeof(struct in6_addr)];
- if (avoid_dns) {
+ while (avoid_dns) {
/*
* Determine if this is a server name, or an IP address.
* If it is an IP address, do the DNS lookup otherwise
* skip the DNS lookup.
*/
- int is_fqdn = 1;
if (strchr(name, '.') == NULL)
- is_fqdn = 0; /* local name */
+ break; /* local name */
else if (inet_pton(AF_INET, name, buf) == 1)
- is_fqdn = 0; /* IPv4 address */
+ break; /* IPv4 address */
else if (inet_pton(AF_INET6, name, buf) == 1)
- is_fqdn = 0; /* IPv6 addrss */
+ break; /* IPv6 addrss */
- if (is_fqdn) {
- return strdup(name);
- }
- /* Sorry, cannot avoid dns after all */
+ return strdup(name);
}
switch (sa->sa_family) {
@@ -233,84 +228,113 @@ get_servername(const char *name, const struct sockaddr *sa, const char *addr)
return NULL;
}
- hostname = strdup(hbuf);
-
- return hostname;
+ return strdup(hbuf);
}
-/* XXX buffer problems: */
-static int
-read_service_info(int fd, char **servicename, char **servername,
- int *prog, int *vers, char **protocol,
- struct sockaddr *addr) {
-#define INFOBUFLEN 256
- char buf[INFOBUFLEN + 1];
- static char server[128];
- int nbytes;
- static char service[128];
- static char address[128];
- char program[16];
- char version[16];
- char protoname[16];
- char port[128];
- char *p;
- int numfields;
-
- *servicename = *servername = *protocol = NULL;
-
- if ((nbytes = read(fd, buf, INFOBUFLEN)) == -1)
+static void
+gssd_read_service_info(int dirfd, struct clnt_info *clp)
+{
+ int fd;
+ FILE *info = NULL;
+ int numfields;
+ char *server = NULL;
+ char *service = NULL;
+ int program;
+ int version;
+ char *address = NULL;
+ char *protoname = NULL;
+ char *port = NULL;
+ char *servername = NULL;
+
+ fd = openat(dirfd, "info", O_RDONLY);
+ if (fd < 0) {
+ printerr(0, "ERROR: can't open %s/info: %s\n",
+ clp->relpath, strerror(errno));
goto fail;
+ }
- buf[nbytes] = '\0';
-
- numfields = sscanf(buf,"RPC server: %127s\n"
- "service: %127s %15s version %15s\n"
- "address: %127s\n"
- "protocol: %15s\n",
- server,
- service, program, version,
- address,
- protoname);
-
- if (numfields == 5) {
- strcpy(protoname, "tcp");
- } else if (numfields != 6) {
+ info = fdopen(fd, "r");
+ if (!info) {
+ printerr(0, "ERROR: can't fdopen %s/info: %s\n",
+ clp->relpath, strerror(errno));
+ close(fd);
goto fail;
}
- port[0] = '\0';
- if ((p = strstr(buf, "port")) != NULL)
- sscanf(p, "port: %127s\n", port);
-
- /* get program, and version numbers */
- *prog = atoi(program + 1); /* skip open paren */
- *vers = atoi(version);
-
- if (!addrstr_to_sockaddr(addr, address, port))
+ /*
+ * Some history:
+ *
+ * The first three lines were added with rpc_pipefs in 2003-01-13.
+ * (commit af2f003391786fb632889c02142c941b212ba4ff)
+ *
+ * The 'protocol' line was added in 2003-06-11.
+ * (commit 9bd741ae48785d0c0e75cf906ff66f893d600c2d)
+ *
+ * The 'port' line was added in 2007-09-26.
+ * (commit bf19aacecbeebccb2c3d150a8bd9416b7dba81fe)
+ */
+ numfields = fscanf(info,
+ "RPC server: %ms\n"
+ "service: %ms (%d) version %d\n"
+ "address: %ms\n"
+ "protocol: %ms\n"
+ "port: %ms\n",
+ &server,
+ &service, &program, &version,
+ &address,
+ &protoname,
+ &port);
+
+
+ switch (numfields) {
+ case 5:
+ protoname = strdup("tcp");
+ if (!protoname)
+ goto fail;
+ /* fall through */
+ case 6:
+ /* fall through */
+ case 7:
+ break;
+ default:
goto fail;
+ }
- *servername = get_servername(server, addr, address);
- if (*servername == NULL)
+ if (!gssd_addrstr_to_sockaddr((struct sockaddr *)&clp->addr,
+ address, port ? port : ""))
goto fail;
- nbytes = snprintf(buf, INFOBUFLEN, "%s@%s", service, *servername);
- if (nbytes > INFOBUFLEN)
+ servername = gssd_get_servername(server, (struct sockaddr *)&clp->addr, address);
+ if (!servername)
goto fail;
- if (!(*servicename = calloc(strlen(buf) + 1, 1)))
+ if (asprintf(&clp->servicename, "%s@%s", service, servername) < 0)
goto fail;
- memcpy(*servicename, buf, strlen(buf));
- if (!(*protocol = strdup(protoname)))
- goto fail;
- return 0;
+ clp->servername = servername;
+ clp->prog = program;
+ clp->vers = version;
+ clp->protocol = protoname;
+
+ goto out;
+
fail:
- printerr(0, "ERROR: failed to read service info\n");
- free(*servername);
- free(*servicename);
- free(*protocol);
- *servicename = *servername = *protocol = NULL;
- return -1;
+ printerr(0, "ERROR: failed to parse %s/info\n", clp->relpath);
+ free(servername);
+ free(protoname);
+ clp->servicename = NULL;
+ clp->servername = NULL;
+ clp->prog = 0;
+ clp->vers = 0;
+ clp->protocol = NULL;
+out:
+ if (info)
+ fclose(info);
+
+ free(server);
+ free(service);
+ free(address);
+ free(port);
}
static void
@@ -475,20 +499,8 @@ gssd_scan_clnt(struct topdir *tdi, const char *name)
/* not fatal, files might appear later */
goto out;
- if (clp->prog == 0) {
- int infofd;
-
- infofd = openat(clntfd, "info", O_RDONLY);
- if (infofd < 0) {
- printerr(0, "ERROR: can't open %s/info: %s\n",
- clp->relpath, strerror(errno));
- } else {
- read_service_info(infofd, &clp->servicename,
- &clp->servername, &clp->prog, &clp->vers,
- &clp->protocol, (struct sockaddr *) &clp->addr);
- close(infofd);
- }
- }
+ if (clp->prog == 0)
+ gssd_read_service_info(clntfd, clp);
out:
close(clntfd);
@@ -692,7 +704,7 @@ main(int argc, char *argv[])
#endif
break;
case 'D':
- avoid_dns = 0;
+ avoid_dns = false;
break;
default:
usage(argv[0]);
--
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