application/pwd.c

changeset 6
09ac07345656
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/application/pwd.c	Mon Jan 29 10:41:00 2024 +0100
@@ -0,0 +1,472 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2018 Olaf Wintermann. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "pwd.h"
+
+#include <cx/buffer.h>
+#include <cx/utils.h>
+#include <cx/hash_map.h>
+
+#ifdef _WIN32
+#include <winsock.h>
+#pragma comment(lib, "Ws2_32.lib")
+#else
+#include <netinet/in.h>
+#endif
+
+PwdStore* pwdstore_open(const char *file) {
+    FILE *in = fopen(file, "r");
+    if(!in) {
+        return NULL;
+    }
+    
+    CxBuffer *buf = cxBufferCreate(NULL, 2048, cxDefaultAllocator, CX_BUFFER_FREE_CONTENTS|CX_BUFFER_AUTO_EXTEND);
+    cx_stream_copy(in, buf, (cx_read_func)fread, (cx_write_func)cxBufferWrite);
+    fclose(in);
+    
+    if(buf->size < PWDS_HEADER_SIZE || buf->space[0] != PWDS_MAGIC_CHAR) {
+        cxBufferFree(buf);
+        return NULL;
+    }
+    
+    PwdStore *p = malloc(sizeof(PwdStore));
+    p->ids = cxHashMapCreate(cxDefaultAllocator, CX_STORE_POINTERS, 16);
+    p->locations = cxLinkedListCreateSimple(CX_STORE_POINTERS);
+    p->noloc = cxLinkedListCreateSimple(CX_STORE_POINTERS);
+    p->index = cxHashMapCreate(cxDefaultAllocator, CX_STORE_POINTERS, 16);
+    p->content = buf;
+    p->key = NULL;
+    p->unlock_cmd = NULL;
+    p->lock_cmd = NULL;
+    p->encoffset = PWDS_HEADER_SIZE;
+    p->isdecrypted = 0;
+    
+    if(pwdstore_getindex(p)) {
+        pwdstore_free(p);
+        return NULL;
+    }
+    
+    return p;
+}
+
+PwdStore* pwdstore_new(void) {
+    PwdStore *p = calloc(1, sizeof(PwdStore));
+    p->ids = cxHashMapCreate(cxDefaultAllocator, CX_STORE_POINTERS, 16);
+    p->locations = cxLinkedListCreateSimple(CX_STORE_POINTERS);
+    p->noloc = cxLinkedListCreateSimple(CX_STORE_POINTERS);
+    p->index = cxHashMapCreate(cxDefaultAllocator, CX_STORE_POINTERS, 16);
+    p->content = cxBufferCreate(NULL, PWDS_HEADER_SIZE, cxDefaultAllocator, CX_BUFFER_FREE_CONTENTS|CX_BUFFER_AUTO_EXTEND);
+    PWDS_MAGIC(p) = PWDS_MAGIC_CHAR;
+    PWDS_VERSION(p) = 1;
+    PWDS_ENC(p) = DAV_KEY_AES256;
+    PWDS_PWFUNC(p) = DAV_PWFUNC_PBKDF2_SHA256;
+    dav_rand_bytes((unsigned char*)p->content->space+4, 16);
+    p->isdecrypted = 1;
+    p->encoffset = PWDS_HEADER_SIZE;
+    return p;
+}
+
+static int readval(CxBuffer *in, char **val, int allowzero) {
+    // value  = length string
+    // length = uint32
+    // string = bytes
+    
+    *val = NULL;
+    
+    // get length
+    uint32_t length = 0;
+    if(cxBufferRead(&length, 1, sizeof(uint32_t), in) != sizeof(uint32_t)) {
+        return 0;
+    }
+    length = ntohl(length); // convert from BE to host byte order
+    if(length == 0) {
+        if(allowzero) {
+            return 1;
+        } else {
+            return 0;
+        }
+    }
+    if(length > PWDSTORE_MAX_LEN) {
+        return 0;
+    }
+    
+    // get value
+    char *value = malloc(length + 1);
+    value[length] = 0;
+    if(cxBufferRead(value, 1, length, in) != length) {
+        free(value);
+        return 0;
+    }
+    
+    *val = value;
+    return 1;
+}
+
+static int read_indexentry(PwdStore *p, CxBuffer *in) {
+    // read type of index element
+    int type = cxBufferGet(in);
+    if(type == EOF || type != 0) {
+        // only type 0 supported yet
+        return 0;
+    }
+      
+    char *id = NULL;
+    CxList *locations = cxLinkedListCreateSimple(CX_STORE_POINTERS);
+    locations->simple_destructor = free;
+    
+    // get id (required)
+    int ret = 0;
+    if(readval(in, &id, FALSE)) {
+        ret = 1;
+        // get locations
+        char *location = NULL;
+        while((ret = readval(in, &location, TRUE)) == 1) {
+            if(!location) {
+                break;
+            }
+            cxListAdd(locations, location);
+        }
+    }
+    
+    if(ret) {
+        pwdstore_put_index(p, id, locations);
+    } else {
+        if(id) free(id);
+        cxListDestroy(locations);
+    }
+    
+    return ret;
+}
+
+static int read_pwdentry(PwdStore *p, CxBuffer *in) {
+    int type = cxBufferGet(in);
+    if(type == EOF || type != 0) {
+        // only type 0 supported yet
+        return 0;
+    }
+    
+    char *id = NULL;
+    char *location = NULL;
+    char *user = NULL;
+    char *password = NULL;
+    
+    int ret = 0;
+    if(readval(in, &id, FALSE)) {
+        if(readval(in, &user, FALSE)) {
+            if(readval(in, &password, FALSE)) {
+                pwdstore_put(p, id, user, password);
+                ret = 1;
+            }
+        }
+    }
+    
+    if(id) free(id);
+    if(location) free(location);
+    if(user) free(user);
+    if(password) free(password);
+    
+    return ret;
+}
+
+static int remove_list_entries(PwdStore *s, const char *id) {
+    int ret = 0;
+    
+    CxList *loc_entry = NULL;
+    CxList *noloc_entry = NULL;
+    
+    CxMutIterator i = cxListMutIterator(s->locations);
+    cx_foreach(PwdIndexEntry*, ie, i) {
+        if(!strcmp(ie->id, id)) {
+            cxIteratorFlagRemoval(i);
+            // TODO: break loop
+        }
+    }
+    i = cxListMutIterator(s->noloc);
+    cx_foreach(PwdIndexEntry*, ie, i) {
+        if(!strcmp(ie->id, id)) {
+            cxIteratorFlagRemoval(i);
+            // TODO: break loop
+        }
+    }
+    
+    return ret;
+}
+
+void pwdstore_remove_entry(PwdStore *s, const char *id) {
+    while(remove_list_entries(s, id)) {}
+    
+    CxHashKey key = cx_hash_key_str(id);
+    PwdIndexEntry *i = cxMapRemoveAndGet(s->index, key);
+    PwdEntry *e = cxMapRemoveAndGet(s->ids, key);
+    
+    if(i) {
+        cxListDestroy(i->locations);
+        free(i->id);
+        free(i);
+    }
+    if(e) {
+        free(e->id);
+        free(e->user);
+        free(e->password);
+        free(e);
+    }
+}
+
+int pwdstore_getindex(PwdStore *s) {
+    uint32_t netindexlen;
+    
+    // set the position to the last 4 bytes of the header
+    // for reading index length
+    s->content->pos = PWDS_HEADER_SIZE - sizeof(uint32_t);
+    
+    // read indexlen and convert to host byte order
+    if(cxBufferRead(&netindexlen, 1, sizeof(uint32_t), s->content) != sizeof(uint32_t)) {
+        return 1;
+    }
+    uint32_t indexlen = ntohl(netindexlen);
+    
+    // integer overflow check
+    if(UINT32_MAX - PWDS_HEADER_SIZE < indexlen) {
+        return 1;
+    }
+    if(s->content->size < PWDS_HEADER_SIZE + indexlen) {
+        return 1;
+    }
+    // encrypted content starts after the index content
+    s->encoffset = PWDS_HEADER_SIZE + indexlen;
+    
+    // the index starts after the header
+    CxBuffer *index = cxBufferCreate(s->content->space+PWDS_HEADER_SIZE, indexlen, cxDefaultAllocator, 0);
+    index->size = indexlen;
+    
+    // read index
+    while(read_indexentry(s, index)) {}
+    
+    // free index buffer structure (not the content)
+    cxBufferFree(index);
+    
+    return 0;
+}
+
+int pwdstore_decrypt(PwdStore *p) {
+    if(!p->key) {
+        return 1;
+    }
+    if(p->isdecrypted) {
+        return 0;
+    }
+    
+    // decrypt contet
+    size_t encsz = p->content->size - p->encoffset;
+    CxBuffer *enc = cxBufferCreate(p->content->space + p->encoffset, encsz, cxDefaultAllocator, 0);
+    enc->size = encsz;
+    enc->size = p->content->size - p->encoffset;
+    CxBuffer *content = aes_decrypt_buffer(enc, p->key);
+    cxBufferFree(enc);
+    if(!content) {
+        return 1;
+    }
+    
+    while(read_pwdentry(p, content)) {}
+    
+    cxBufferFree(content);
+    
+    return 0;
+}
+
+int pwdstore_setpassword(PwdStore *p, const char *password) {
+    DavKey *key = dav_pw2key(
+            password,
+            (unsigned char*)(p->content->space + 4),
+            16,
+            PWDS_PWFUNC(p),
+            PWDS_ENC(p));
+    if(!key) {
+        return 1;
+    }
+    
+    p->key = key;
+    return 0;
+}
+
+void pwdstore_encsettings(PwdStore *p, uint8_t enc, uint8_t pwfunc) {
+    PWDS_ENC(p) = enc;
+    PWDS_PWFUNC(p) = pwfunc;
+}
+
+void pwdstore_free_entry(PwdEntry *e) {
+    if(e->id) free(e->id);
+    if(e->user) free(e->user);
+    if(e->password) free(e->password);
+    free(e);
+}
+
+void pwdstore_free(PwdStore* p) {
+    p->ids->simple_destructor = (cx_destructor_func)pwdstore_free_entry;
+    cxMapDestroy(p->ids);
+    
+    cxListDestroy(p->locations);
+    
+    if(p->content) {
+        cxBufferFree(p->content);
+    }
+    
+    free(p);
+}
+
+int pwdstore_has_id(PwdStore *s, const char *id) {
+    return cxMapGet(s->index, cx_hash_key_str(id)) ? 1 : 0;
+}
+
+PwdEntry* pwdstore_get(PwdStore *p, const char *id) {
+    PwdEntry *e = cxMapGet(p->ids, cx_hash_key_str(id));
+    if(e && e->user && e->password) {
+        return e;
+    } else {
+        return NULL;
+    }
+}
+
+void pwdstore_put(PwdStore *p, const char *id, const char *username, const char *password) {
+    PwdEntry *entry = malloc(sizeof(PwdEntry));
+    entry->id = strdup(id);
+    entry->user = strdup(username);
+    entry->password = strdup(password);
+    cxMapPut(p->ids, cx_hash_key_str(id), entry);
+}
+
+void pwdstore_put_index(PwdStore *p, char *id, CxList *locations) {
+    PwdIndexEntry *e = cxMapGet(p->index, cx_hash_key_str(id));
+    if(e) {
+        return;
+    }
+    PwdIndexEntry *newentry = malloc(sizeof(PwdIndexEntry));
+    newentry->id = id;
+    if(locations) {
+        newentry->locations = locations;
+        cxListAdd(p->locations, newentry);
+    } else {
+        newentry->locations = NULL;
+        cxListAdd(p->noloc, newentry);
+    }
+    cxMapPut(p->index, cx_hash_key_str(id), newentry);
+}
+
+void write_index_entry(CxBuffer *out, PwdIndexEntry *e) {
+    uint32_t idlen = strlen(e->id);
+    uint32_t netidlen = htonl(idlen);
+    
+    cxBufferPut(out, 0); // type
+
+    cxBufferWrite(&netidlen, 1, sizeof(uint32_t), out);
+    cxBufferWrite(e->id, 1, idlen, out);
+    
+    CxIterator i = cxListIterator(e->locations);
+    cx_foreach(char *, location, i) {
+        uint32_t locationlen = strlen(location);
+        uint32_t netlocationlen = htonl(locationlen);
+        
+        cxBufferWrite(&netlocationlen, 1, sizeof(uint32_t), out);
+        cxBufferWrite(location, 1, locationlen, out);
+    }
+    
+    uint32_t terminate = 0;
+    cxBufferWrite(&terminate, 1, sizeof(uint32_t), out);
+}
+
+int pwdstore_store(PwdStore *p, const char *file) {
+    if(!p->key) {
+        return 1;
+    }
+    
+    CxBuffer *index = cxBufferCreate(NULL, 2048, cxDefaultAllocator, CX_BUFFER_FREE_CONTENTS|CX_BUFFER_AUTO_EXTEND);
+    CxBuffer *content = cxBufferCreate(NULL, 2048, cxDefaultAllocator, CX_BUFFER_FREE_CONTENTS|CX_BUFFER_AUTO_EXTEND);
+    
+    // create index
+    CxIterator i = cxListIterator(p->noloc);
+    cx_foreach(PwdIndexEntry*, e, i) {
+        write_index_entry(index, e);
+    }
+    i = cxListIterator(p->locations);
+    cx_foreach(PwdIndexEntry*, e, i) {
+        write_index_entry(index, e);
+    }
+    
+    i = cxMapIteratorValues(p->ids);
+    cx_foreach(PwdEntry*, value, i) {
+        if(!value->id || !value->user || !value->password) {
+            continue;
+        }
+        
+        uint32_t idlen = strlen(value->id);
+        uint32_t ulen = strlen(value->user);
+        uint32_t plen = strlen(value->password);
+        uint32_t netidlen = htonl(idlen);
+        uint32_t netulen = htonl(ulen);
+        uint32_t netplen = htonl(plen);
+        
+        // content buffer
+        cxBufferPut(content, 0); // type
+        
+        cxBufferWrite(&netidlen, 1, sizeof(uint32_t), content);
+        cxBufferWrite(value->id, 1, idlen, content);
+        cxBufferWrite(&netulen, 1, sizeof(uint32_t), content);
+        cxBufferWrite(value->user, 1, ulen, content);
+        cxBufferWrite(&netplen, 1, sizeof(uint32_t), content);
+        cxBufferWrite(value->password, 1, plen, content);
+    }
+      
+    content->pos = 0;
+    CxBuffer *enc = aes_encrypt_buffer(content, p->key);
+
+    p->content->pos = PWDS_HEADER_SIZE - sizeof(uint32_t);
+    p->content->size = PWDS_HEADER_SIZE;
+    
+    // add index after header
+    uint32_t netindexlen = htonl((uint32_t)index->size);
+    cxBufferWrite(&netindexlen, 1, sizeof(uint32_t), p->content);
+    cxBufferWrite(index->space, 1, index->size, p->content);
+    
+    // add encrypted buffer
+    cxBufferWrite(enc->space, 1, enc->size, p->content);
+    
+    cxBufferFree(enc);
+    
+    FILE *out = fopen(file, "w");
+    if(!out) {
+        return 1;
+    }
+    fwrite(p->content->space, 1, p->content->size, out);
+    fclose(out);
+    
+    return 0;
+}

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