diff options
Diffstat (limited to 'moon-abe/cpabe-0.11/common.c')
| -rw-r--r-- | moon-abe/cpabe-0.11/common.c | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/moon-abe/cpabe-0.11/common.c b/moon-abe/cpabe-0.11/common.c new file mode 100644 index 00000000..ee40c809 --- /dev/null +++ b/moon-abe/cpabe-0.11/common.c @@ -0,0 +1,257 @@ +#include <stdio.h> +#include <stdarg.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#include <assert.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <unistd.h> +#include <glib.h> +#include <openssl/aes.h> +#include <openssl/sha.h> +#include <pbc.h> + +#include "common.h" + +void +init_aes( element_t k, int enc, AES_KEY* key, unsigned char* iv ) +{ + int key_len; + unsigned char* key_buf; + + key_len = element_length_in_bytes(k) < 17 ? 17 : element_length_in_bytes(k); + key_buf = (unsigned char*) malloc(key_len); + element_to_bytes(key_buf, k); + + if( enc ) + AES_set_encrypt_key(key_buf + 1, 128, key); + else + AES_set_decrypt_key(key_buf + 1, 128, key); + free(key_buf); + + memset(iv, 0, 16); +} + +GByteArray* +aes_128_cbc_encrypt( GByteArray* pt, element_t k ) +{ + AES_KEY key; + unsigned char iv[16]; + GByteArray* ct; + guint8 len[4]; + guint8 zero; + + init_aes(k, 1, &key, iv); + + /* TODO make less crufty */ + + /* stuff in real length (big endian) before padding */ + len[0] = (pt->len & 0xff000000)>>24; + len[1] = (pt->len & 0xff0000)>>16; + len[2] = (pt->len & 0xff00)>>8; + len[3] = (pt->len & 0xff)>>0; + g_byte_array_prepend(pt, len, 4); + + /* pad out to multiple of 128 bit (16 byte) blocks */ + zero = 0; + while( pt->len % 16 ) + g_byte_array_append(pt, &zero, 1); + + ct = g_byte_array_new(); + g_byte_array_set_size(ct, pt->len); + + AES_cbc_encrypt(pt->data, ct->data, pt->len, &key, iv, AES_ENCRYPT); + + return ct; +} + +GByteArray* +aes_128_cbc_decrypt( GByteArray* ct, element_t k ) +{ + AES_KEY key; + unsigned char iv[16]; + GByteArray* pt; + unsigned int len; + + init_aes(k, 0, &key, iv); + + pt = g_byte_array_new(); + g_byte_array_set_size(pt, ct->len); + + AES_cbc_encrypt(ct->data, pt->data, ct->len, &key, iv, AES_DECRYPT); + + /* TODO make less crufty */ + + /* get real length */ + len = 0; + len = len + | ((pt->data[0])<<24) | ((pt->data[1])<<16) + | ((pt->data[2])<<8) | ((pt->data[3])<<0); + g_byte_array_remove_index(pt, 0); + g_byte_array_remove_index(pt, 0); + g_byte_array_remove_index(pt, 0); + g_byte_array_remove_index(pt, 0); + + /* truncate any garbage from the padding */ + g_byte_array_set_size(pt, len); + + return pt; +} + +FILE* +fopen_read_or_die( char* file ) +{ + FILE* f; + + if( !(f = fopen(file, "r")) ) + die("can't read file: %s\n", file); + + return f; +} + +FILE* +fopen_write_or_die( char* file ) +{ + FILE* f; + + if( !(f = fopen(file, "w")) ) + die("can't write file: %s\n", file); + + return f; +} + +GByteArray* +suck_file( char* file ) +{ + FILE* f; + GByteArray* a; + struct stat s; + + a = g_byte_array_new(); + stat(file, &s); + g_byte_array_set_size(a, s.st_size); + + f = fopen_read_or_die(file); + fread(a->data, 1, s.st_size, f); + fclose(f); + + return a; +} + +char* +suck_file_str( char* file ) +{ + GByteArray* a; + char* s; + unsigned char zero; + + a = suck_file(file); + zero = 0; + g_byte_array_append(a, &zero, 1); + s = (char*) a->data; + g_byte_array_free(a, 0); + + return s; +} + +char* +suck_stdin() +{ + GString* s; + char* r; + int c; + + s = g_string_new(""); + while( (c = fgetc(stdin)) != EOF ) + g_string_append_c(s, c); + + r = s->str; + g_string_free(s, 0); + + return r; +} + +void +spit_file( char* file, GByteArray* b, int free ) +{ + FILE* f; + + f = fopen_write_or_die(file); + fwrite(b->data, 1, b->len, f); + fclose(f); + + if( free ) + g_byte_array_free(b, 1); +} + +void read_cpabe_file( char* file, GByteArray** cph_buf, + int* file_len, GByteArray** aes_buf ) +{ + FILE* f; + int i; + int len; + + *cph_buf = g_byte_array_new(); + *aes_buf = g_byte_array_new(); + + f = fopen_read_or_die(file); + + /* read real file len as 32-bit big endian int */ + *file_len = 0; + for( i = 3; i >= 0; i-- ) + *file_len |= fgetc(f)<<(i*8); + + /* read aes buf */ + len = 0; + for( i = 3; i >= 0; i-- ) + len |= fgetc(f)<<(i*8); + g_byte_array_set_size(*aes_buf, len); + fread((*aes_buf)->data, 1, len, f); + + /* read cph buf */ + len = 0; + for( i = 3; i >= 0; i-- ) + len |= fgetc(f)<<(i*8); + g_byte_array_set_size(*cph_buf, len); + fread((*cph_buf)->data, 1, len, f); + + fclose(f); +} + +void +write_cpabe_file( char* file, GByteArray* cph_buf, + int file_len, GByteArray* aes_buf ) +{ + FILE* f; + int i; + + f = fopen_write_or_die(file); + + /* write real file len as 32-bit big endian int */ + for( i = 3; i >= 0; i-- ) + fputc((file_len & 0xff<<(i*8))>>(i*8), f); + + /* write aes_buf */ + for( i = 3; i >= 0; i-- ) + fputc((aes_buf->len & 0xff<<(i*8))>>(i*8), f); + fwrite(aes_buf->data, 1, aes_buf->len, f); + + /* write cph_buf */ + for( i = 3; i >= 0; i-- ) + fputc((cph_buf->len & 0xff<<(i*8))>>(i*8), f); + fwrite(cph_buf->data, 1, cph_buf->len, f); + + fclose(f); +} + +void +die(char* fmt, ...) +{ + va_list args; + va_start(args, fmt); + vfprintf(stderr, fmt, args); + va_end(args); + exit(1); +} |