introcude authfile module

[pam_pcsc_cr.git] / authfile.c

diff --git a/authfile.c b/authfile.c
new file mode 100644 (file)
index 0000000..1e0826d
--- /dev/null
+++ b/authfile.c
@@ -0,0 +1,120 @@
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <alloca.h>
+#include "authobj.h"
+#include "authfile.h"
+#include "pcsc_cr.h"
+
+#define OBJSIZE 256
+
+int update_authfile(const char *fn, const char *tokenid, const char *id,
+                const char *password, const char *nonce,
+                const unsigned char *secret, const int secsize,
+                const unsigned char *payload, const int paysize)
+{
+       FILE *fp;
+       int rc;
+       int i;
+       unsigned char key[20];
+       int keysize = sizeof(key);
+       unsigned char mysecret[20];
+       int mysecsize = sizeof(mysecret);
+       unsigned char myload[256];
+       int myloadsize = sizeof(myload);
+       unsigned char *authobj = alloca(OBJSIZE);
+       int authsize = OBJSIZE;
+       char buf[512];
+       char *oldtokenid = NULL, *oldid = NULL, *oldnonce = NULL,
+               *hauthobj = NULL;
+       unsigned char *oldauthobj = NULL;
+       int oldauthsize;
+
+       if ((fp = fopen(fn, "r"))) {
+               if (fgets(buf, sizeof(buf), fp)) {
+                       oldtokenid = strtok(buf, ":\r\n");
+                       oldid = strtok(NULL, ":\r\n");
+                       oldnonce = strtok(NULL, ":\r\n");
+                       hauthobj = strtok(NULL, ":\r\n");
+               } else {
+                       eprint("error reading from %s: %s\n",
+                               fn, strerror(errno));
+               }
+               fclose(fp);
+       }
+       if (hauthobj) {
+               int hlen;
+
+               hlen = strlen(hauthobj);
+               if (hlen % 32 != 0) {
+                       eprint("error: auth string has wrong length\n");
+               } else if (hlen !=
+                               strspn(hauthobj, "0123456789abcdefABCDEF")) {
+                       eprint("error: auth string not hexadecimal\n");
+               } else {
+                       oldauthsize = hlen/2;
+                       oldauthobj = alloca(oldauthsize);
+                       for (i = 0; i < oldauthsize; i++)
+                               sscanf(&hauthobj[i*2], "%2hhx", &oldauthobj[i]);
+               }
+       }
+
+       if (oldauthobj && password && !secret) {
+               unsigned char chal[64];
+               int csize = sizeof(chal);
+               long rc;
+
+               rc = make_challenge(id, password, nonce, chal, &csize);
+               if (rc) {
+                       eprint("cannot make challenge\n");
+                       return -1;
+               }
+               rc = pcsc_cr(chal, csize, key, &keysize);
+               if (rc) {
+                       eprint("error querying token: %s\n", pcsc_errstr(rc));
+                       return -1;
+               }
+               rc = parse_authobj(key, keysize, oldauthobj, oldauthsize,
+                       mysecret, &mysecsize, myload, &myloadsize);
+               if (rc) {
+                       eprint("cannot parse old authobj: %d\n", rc);
+                       return -1;
+               }
+       }
+
+       rc = make_authobj(id, password, nonce, mysecret, mysecsize,
+                       payload, paysize, authobj, &authsize);
+       if (rc) {
+               eprint("make_authobj error %d\n", rc);
+               return -1;
+       }
+       fp = fopen(fn, "w");
+       if (!fp) {
+               eprint("cannot open \"%s\": %s\n",
+                       fn, strerror(errno));
+               return -1;
+       }
+       if (fprintf(fp, "%s:%s:%s:", tokenid, id, nonce) < 0) {
+               eprint("cannot write to \"%s\": %s\n",
+                       fn, strerror(errno));
+               return -1;
+       }
+       for (i = 0; i < authsize; i++)
+           if (fprintf(fp, "%02x", authobj[i]) < 0) {
+               eprint("cannot write to \"%s\": %s\n",
+                       fn, strerror(errno));
+               return -1;
+       }
+       fprintf(fp, "\n");
+       if (fclose(fp) < 0) {
+               eprint("cannot close \"%s\": %s\n",
+                       fn, strerror(errno));
+               return -1;
+       }
+       return 0;
+}