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[pam_pcsc_cr.git] / authfile.c

diff --git a/authfile.c b/authfile.c
index f7daa60eec5f0c3de4b8596b3bbf481a610f7c89..325c29d7a4e66ea96bd79e1efdc47f25b42dc7f1 100644 (file)
--- a/authfile.c
+++ b/authfile.c
@@ -1,9 +1,33 @@
+/*
+Copyright (c) 2013 Eugene Crosser
+
+This software is provided 'as-is', without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+    1. The origin of this software must not be misrepresented; you must
+    not claim that you wrote the original software. If you use this
+    software in a product, an acknowledgment in the product documentation
+    would be appreciated but is not required.
+
+    2. Altered source versions must be plainly marked as such, and must
+    not be misrepresented as being the original software.
+
+    3. This notice may not be removed or altered from any source
+    distribution.
+*/
+

 #ifdef HAVE_CONFIG_H
 # include "config.h"
 #endif
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <pwd.h>
 #ifdef HAVE_CONFIG_H
 # include "config.h"
 #endif
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <pwd.h>

+#include <time.h>

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>


@@ -26,9 +50,9 @@
  * string.
  */
 
  * string.
  */
 

-static char *template = "~/.pam_cr/auth";
+static const char *template = "~/.pam_cr/auth";

 
 

-void authfile_template(char *str)
+void authfile_template(const char *str)

 {
        template = str;
 }
 {
        template = str;
 }


@@ -36,7 +60,7 @@ void authfile_template(char *str)
 static int path_size(const char *tokenid, const char *userid)
 {
        const char *usub;
 static int path_size(const char *tokenid, const char *userid)
 {
        const char *usub;

-       char *p, *q;
+       const char *p, *q;

        struct passwd *pw;
 
        if ((p = strchr(template, '~')) != strrchr(template, '~')) return 0;
        struct passwd *pw;
 
        if ((p = strchr(template, '~')) != strrchr(template, '~')) return 0;


@@ -50,14 +74,15 @@ static int path_size(const char *tokenid, const char *userid)
        } else {
                usub = userid;
        }
        } else {
                usub = userid;
        }

-       return strlen(template) + p?strlen(usub):0 + q?strlen(tokenid):0 + 1;
+       return strlen(template)+(p?strlen(usub):0)+(q?strlen(tokenid):0)+1;

 }
 
 static void
 make_path(char * const path, const char *tokenid, const char *userid)
 {
        const char *usub;
 }
 
 static void
 make_path(char * const path, const char *tokenid, const char *userid)
 {
        const char *usub;

-       char *p, *q;
+       const char *p;
+       char *q;

        struct passwd *pw;
 
        path[0] = '\0';
        struct passwd *pw;
 
        path[0] = '\0';


@@ -85,6 +110,19 @@ make_path(char * const path, const char *tokenid, const char *userid)
        *q = '\0';
 }
 
        *q = '\0';
 }
 

+int parse(char * const buf, const int argc, const char *argv[const])
+{
+       char *p, *q;
+       int i;
+
+       for (i = 0, p = buf; *p; p = q+1, i++) {
+               for (q = p; *q && *q != ':' && *q != '\r' && *q != '\n'; q++) ;
+               *q = '\0';
+               if (*p && i < argc) argv[i] = p;
+       }
+       return i != argc;
+}
+

 struct _auth_obj authfile(const char *tokenid,
                const char *userid, const char *password,
                void (*update_nonce)(char *nonce, const int nonsize),
 struct _auth_obj authfile(const char *tokenid,
                const char *userid, const char *password,
                void (*update_nonce)(char *nonce, const int nonsize),


@@ -96,11 +134,16 @@ struct _auth_obj authfile(const char *tokenid,
        struct _auth_obj ret = {0};
        mode_t oldmask;
        FILE *fp = NULL;
        struct _auth_obj ret = {0};
        mode_t oldmask;
        FILE *fp = NULL;

-       char *fn;
+       char *fn, *nfn;

        int fnl;
        int fnl;

+       struct stat st = {0};

        char *buf = NULL;
        char *buf = NULL;

-       const char *wtokenid = "", *wuserid = NULL, *wnonce = NULL;
-       const char *hablob = NULL;
+       struct {
+               const char *tokenid;
+               const char *userid;
+               const char *nonce;
+               const char *hablob;
+       } w = {"", NULL, NULL, NULL};

        unsigned char *ablob = NULL;
        int blobsize = 0;
        char *newnonce;
        unsigned char *ablob = NULL;
        int blobsize = 0;
        char *newnonce;


@@ -113,36 +156,29 @@ struct _auth_obj authfile(const char *tokenid,
        }
        fn = alloca(fnl);
        make_path(fn, tokenid, userid);
        }
        fn = alloca(fnl);
        make_path(fn, tokenid, userid);

+       nfn = alloca(fnl+32);
+       snprintf(nfn, fnl+32, "%s.%d.%ld", fn, (int)getpid(), (long)time(NULL));

        fp = fopen(fn, "r");
        if (fp) {
        fp = fopen(fn, "r");
        if (fp) {

-               struct stat st;
-               int fd = fileno(fp);
-
-               if (fstat(fd, &st)) st.st_size = 2047;
+               if (fstat(fileno(fp), &st)) st.st_size = 2047;

                if (st.st_size > 2047) st.st_size = 2047;
                buf = alloca(st.st_size + 1);
                if (st.st_size > 2047) st.st_size = 2047;
                buf = alloca(st.st_size + 1);

-               if (fgets(buf, st.st_size + 1, fp)) {
-                       char *p;
-
-                       p = &buf[strlen(buf) - 1];
-                       while (*p == '\n' || *p == '\r') *p-- = '\0';
-                       wtokenid = strtok(buf, ":");
-                       wuserid = strtok(NULL, ":");
-                       wnonce = strtok(NULL, ":");
-                       hablob = strtok(NULL, ":");
-               } else {
+               if (!fgets(buf, st.st_size + 1, fp)) {

                        ret.err = strerror(errno);
                        ret.err = strerror(errno);

+               } else if (parse(buf, sizeof(w)/sizeof(char*),
+                                       (const char ** const)&w)){
+                       ret.err = "error: unparseable auth file";

                }
                fclose(fp);
        }
        if (ret.err) return ret;
 
                }
                fclose(fp);
        }
        if (ret.err) return ret;
 

-       if (hablob) {
-               int hlen = strlen(hablob);
+       if (w.hablob) {
+               int hlen = strlen(w.hablob);

                if (hlen % 32 != 0) {
                        ret.err = "error: auth string has wrong length";
                } else if (hlen !=
                if (hlen % 32 != 0) {
                        ret.err = "error: auth string has wrong length";
                } else if (hlen !=

-                               strspn(hablob, "0123456789abcdefABCDEF")) {
+                               strspn(w.hablob, "0123456789abcdefABCDEF")) {

                        ret.err = "error: auth string not hexadecimal";
                } else {
                        int i;
                        ret.err = "error: auth string not hexadecimal";
                } else {
                        int i;


@@ -150,20 +186,20 @@ struct _auth_obj authfile(const char *tokenid,
                        blobsize = hlen/2;
                        ablob = alloca(blobsize);
                        for (i = 0; i < blobsize; i++)
                        blobsize = hlen/2;
                        ablob = alloca(blobsize);
                        for (i = 0; i < blobsize; i++)

-                               sscanf(&hablob[i*2], "%2hhx", &ablob[i]);
+                               sscanf(&w.hablob[i*2], "%2hhx", &ablob[i]);

                }
        }
        if (ret.err) return ret;
 
                }
        }
        if (ret.err) return ret;
 

-       nonsize = wnonce ? strlen(wnonce)*2 : 32;
+       nonsize = w.nonce ? strlen(w.nonce)*2 : 32;

        if (nonsize < 32) nonsize = 32;
        newnonce = alloca(nonsize);
        if (nonsize < 32) nonsize = 32;
        newnonce = alloca(nonsize);

-       if (wnonce) strcpy(newnonce, wnonce);
+       if (w.nonce) strcpy(newnonce, w.nonce);

        else memset(newnonce, 0, nonsize);
        update_nonce(newnonce, nonsize);
 
        else memset(newnonce, 0, nonsize);
        update_nonce(newnonce, nonsize);
 

-       ao = authobj(userid?userid:wuserid, password,
-                       wnonce, newnonce, secret, secsize,
+       ao = authobj(userid?userid:w.userid, password,
+                       w.nonce, newnonce, secret, secsize,

                        payload, paylsize, ablob, blobsize,
                        fetch_key);
 
                        payload, paylsize, ablob, blobsize,
                        fetch_key);
 


@@ -176,17 +212,20 @@ struct _auth_obj authfile(const char *tokenid,
        }
 
        oldmask = umask(077);
        }
 
        oldmask = umask(077);

-       if ((fp = fopen(fn, "w"))) {
+       if ((fp = fopen(nfn, "w"))) {

                int i;
 
                int i;
 

-               if (fprintf(fp, "%s:%s:%s:", tokenid?tokenid:wtokenid,
-                               userid?userid:wuserid, newnonce) < 0) {
+               if (fprintf(fp, "%s:%s:%s:", tokenid?tokenid:w.tokenid,
+                               userid?userid:w.userid, newnonce) < 0) {

                        ret.err = strerror(errno);
                } else for (i = 0; i < ao.datasize; i++)
                    if (fprintf(fp, "%02x", ao.data[i]) < 0) {
                        ret.err = strerror(errno);
                }
                fprintf(fp, "\n");
                        ret.err = strerror(errno);
                } else for (i = 0; i < ao.datasize; i++)
                    if (fprintf(fp, "%02x", ao.data[i]) < 0) {
                        ret.err = strerror(errno);
                }
                fprintf(fp, "\n");

+               if (st.st_uid || st.st_gid) {
+                       (void)fchown(fileno(fp), st.st_uid, st.st_gid);
+               }

                if (fclose(fp) < 0) {
                        ret.err = strerror(errno);
                }
                if (fclose(fp) < 0) {
                        ret.err = strerror(errno);
                }


@@ -194,24 +233,30 @@ struct _auth_obj authfile(const char *tokenid,
                ret.err = strerror(errno);
        }
        (void)umask(oldmask);
                ret.err = strerror(errno);
        }
        (void)umask(oldmask);

+       if (ret.err) {
+               unlink(nfn); /* may not exist but no matter */
+       } else if (rename(nfn, fn)) {
+               ret.err = strerror(errno);
+       }

 
        if (!ret.err) {
 
        if (!ret.err) {

-               int bufsize = (wuserid?strlen(wuserid)+1:0) + ao.paylsize;
+               int bufsize = (w.userid?strlen(w.userid)+1:0) + ao.paylsize + 1;

                if (bufsize) {
                        if ((ret.buffer = malloc(bufsize)) == NULL) {
                                ret.err = "authfile malloc failed";
                        } else {
                                unsigned char *p = ret.buffer;
                if (bufsize) {
                        if ((ret.buffer = malloc(bufsize)) == NULL) {
                                ret.err = "authfile malloc failed";
                        } else {
                                unsigned char *p = ret.buffer;

-                               if (wuserid) {
-                                       strcpy((char*)p, wuserid);
+                               if (w.userid) {
+                                       strcpy((char*)p, w.userid);

                                        ret.data = p;
                                        ret.data = p;

-                                       ret.datasize = strlen(wuserid)+1;
-                                       p += strlen(wuserid)+1;
+                                       ret.datasize = strlen(w.userid)+1;
+                                       p += strlen(w.userid)+1;

                                }
                                if (ao.payload) {
                                        memcpy(p, ao.payload, ao.paylsize);
                                }
                                if (ao.payload) {
                                        memcpy(p, ao.payload, ao.paylsize);

+                                       p[ao.paylsize] = '\0';

                                        ret.payload = p;
                                        ret.payload = p;

-                                       ret.paylsize = ao.paylsize;
+                                       ret.paylsize = ao.paylsize+1;

                                }
                        }
                }
                                }
                        }
                }