Practically rewrite all of pegh.c to operate on streams supporting unlimited length files
This commit is contained in:
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1
.gitignore
vendored
1
.gitignore
vendored
@ -1,2 +1,3 @@
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pegh
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pegh.exe
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bla.txt
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28
README.md
28
README.md
@ -14,6 +14,12 @@ pegh -e SUPER_SECRET_1942 <file.txt >file.txt.pegh
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# decrypt file.txt.pegh to file.txt with password SUPER_SECRET_1942
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pegh -d SUPER_SECRET_1942 <file.txt.pegh >file.txt
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# make enrypted backup
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tar czv -C /path/to/dir/ . | pegh SUPER_SECRET_1942 -o foo.tar.gz.pegh
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# extract encrypted backup
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pegh SUPER_SECRET_1942 -d -i foo.tar.gz.pegh | tar xzv
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```
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The easiest way to scale cost/time it takes for bruteforcing is simply to continue doubling -s, on both encryption and decryption commands.
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@ -21,9 +27,18 @@ The easiest way to scale cost/time it takes for bruteforcing is simply to contin
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full help:
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```
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$ pegh -h
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usage: pegh [-demNrpshV] password
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-e encrypt stdin to stdout, default mode
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-d decrypt stdin to stdout
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usage: pegh [options...] password
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-e encrypt input to output, default mode
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-d decrypt input to output
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-i <filename> file to use for input, default stdin
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-o <filename> file to use for output, if set and there is an error and append
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is not set, we try to delete this file before exiting,
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default stdout
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-a append to -o instead of truncate
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-b <max_mb> maximum megabytes of ram to use per read/write buffer, so while
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decrypting/encrypting twice this will be used, but these are
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only allocated after scrypt is finished so max usage will be
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the highest of these only, not both combined, default: 16
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-m <max_mb> maximum megabytes of ram to use when deriving key from password
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with scrypt, applies for encryption AND decryption, must
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almost linearly scale with -N, if too low operation will fail,
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@ -34,8 +49,10 @@ usage: pegh [-demNrpshV] password
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-p <num> scrypt parameter p, only applies for encryption, default 1
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-s <num> multiplication factor to apply to both -N and -m for easy
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work scaling, rounded up to the next highest power of 2,
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BEWARE: -s 32 requires 2G ram, -s 64 requires 4G and so on,
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default: 1
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-h print this usage text
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-q do not print error output to stderr
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-V show version number and format version support then quit
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For additional info on scrypt params refer to:
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@ -63,4 +80,7 @@ Version 0, scrypt key derivation, aes-256-gcm encryption, 51 byte header, 16 byt
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License
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-------
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AGPLv3 for now, message me if you have a problem with this
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pegh.c: AGPLv3 for now, message me if you have a problem with this
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documentation/file format: consider this your choice of MIT, Apache 2, or public domain
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527
pegh.c
527
pegh.c
@ -39,9 +39,8 @@
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#define SCRYPT_P 1
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#define SCRYPT_MAX_MEM_MB 64
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/* tweak initial read buffer size/reads here */
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#define BYTES_PER_READ (1024 * 32) /* 32kb */
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#define INITIAL_BUFFER_SIZE (1024 * 256) /* 256kb, must be at least 2*BYTES_PER_READ */
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/* tweak buffer sizes here, memory use will be twice this */
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#define BUFFER_SIZE_MB 16
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/*
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* pegh file format, numbers are inclusive 0-based byte array indices
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@ -68,7 +67,8 @@
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#define PEGH_VERSION "1.0.0"
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#define KEY_LEN 32 /* 256 bit key required for AES-256 */
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/* 256 bit key required for AES-256 */
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#define KEY_LEN 32
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/* 1 for file format version, 4 for N, 1 for r, 1 for p */
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#define PRE_SALT_LEN 7
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@ -80,31 +80,43 @@
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#define SALT_IV_LEN (SALT_LEN+IV_LEN)
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#define OVERHEAD_LEN (PRE_SALT_LEN+SALT_IV_LEN+GCM_TAG_LEN)
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/*
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* reads buffer_size at a time from in, encrypts with AES-256-GCM, and writes them to out
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*
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* returns 1 on success, 0 on failure
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*
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* these will be read from:
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* plaintext
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* plaintext_len
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* key must be length KEY_LEN
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* iv must be length IV_LEN
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*
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* these will be written into:
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* ciphertext must have the capacity of at least plaintext_len
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* tag must have the capacity of at least GCM_TAG_LEN
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* buffer_size must be non-zero, this function will allocate this twice
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* in/out must be set
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* err can be NULL in which case no messages are printed
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*/
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int gcm_encrypt(unsigned char *plaintext, size_t plaintext_len,
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unsigned char *key,
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unsigned char *iv,
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unsigned char *ciphertext,
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unsigned char *tag)
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int gcm_encrypt(const unsigned char *key, const unsigned char *iv, size_t buffer_size,
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FILE *in, FILE *out, FILE *err
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)
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{
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EVP_CIPHER_CTX *ctx;
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int len, ret = 0;
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/* these are actually mallocd and freed */
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EVP_CIPHER_CTX *ctx = NULL;
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unsigned char *plaintext = NULL, *ciphertext = NULL;
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int exit_code = 0, ciphertext_written;
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size_t plaintext_read;
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do {
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plaintext = malloc(buffer_size);
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if(!plaintext) {
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if(NULL != err)
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fprintf(err, "plaintext memory allocation failed\n");
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break;
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}
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ciphertext = malloc(buffer_size);
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if(!ciphertext) {
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if(NULL != err)
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fprintf(err, "ciphertext memory allocation failed\n");
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break;
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}
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/* Create and initialise the context */
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if(!(ctx = EVP_CIPHER_CTX_new()))
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break;
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@ -114,7 +126,7 @@ int gcm_encrypt(unsigned char *plaintext, size_t plaintext_len,
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break;
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/* Setting IV length is not necessary because the default of 12 bytes (96 bits) will be used
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if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, IV_LEN, NULL))
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if(1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, IV_LEN, NULL))
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break;
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*/
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@ -125,232 +137,312 @@ int gcm_encrypt(unsigned char *plaintext, size_t plaintext_len,
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/*
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* Provide the message to be encrypted, and obtain the encrypted output.
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* EVP_EncryptUpdate can be called multiple times if necessary
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*
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*/
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if(1 != EVP_EncryptUpdate(ctx, ciphertext, &len, plaintext, plaintext_len))
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break;
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while ((plaintext_read = fread(plaintext, 1, buffer_size, in)) > 0) {
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if(1 != EVP_EncryptUpdate(ctx, ciphertext, &ciphertext_written, plaintext, plaintext_read))
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goto fail;
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if(((size_t) ciphertext_written) != plaintext_read) {
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if(NULL != err)
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fprintf(err, "ciphertext_written (%d) != plaintext_read (%lu)\n", ciphertext_written, (unsigned long) plaintext_read);
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goto fail;
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}
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fwrite(ciphertext, 1, ciphertext_written, out);
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}
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/*
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* Finalise the encryption. Normally ciphertext bytes may be written at
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* this stage, but this does not occur in GCM mode
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*/
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if(1 != EVP_EncryptFinal_ex(ctx, ciphertext + len, &len))
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if(1 != EVP_EncryptFinal_ex(ctx, NULL, &ciphertext_written))
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break;
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/* Get the tag */
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ret = EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, GCM_TAG_LEN, tag);
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} while(0);
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/* Get the tag, go ahead and re-use ciphertext as it's not needed anymore */
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if(1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, GCM_TAG_LEN, ciphertext))
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break;
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fwrite(ciphertext, 1, GCM_TAG_LEN, out);
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/* success! */
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exit_code = 1;
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} while(0);
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fail:
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if(plaintext)
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free(plaintext);
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if(ciphertext)
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free(ciphertext);
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/* Clean up */
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if(ctx)
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EVP_CIPHER_CTX_free(ctx);
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return ret;
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if(NULL != err && exit_code != 1) {
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/* print openssl errors */
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ERR_print_errors_fp(err);
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fprintf(err, "encryption failed\n");
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}
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return exit_code;
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}
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/*
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* reads buffer_size at a time from out, decrypts with AES-256-GCM, and writes them to out
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*
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* assumes the GCM authentication tag is the last 16 bytes and checks that too, it's the
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* responsibility of the calling function to then go back in time and not use the invalid
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* bytes already written to out...
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*
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* returns 1 on success, 0 on failure
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*
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* these will be read from:
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* ciphertext
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* ciphertext_len
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* key must be length KEY_LEN
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* iv must be length IV_LEN
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* tag must be length GCM_TAG_LEN
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*
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* these will be written into:
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* plaintext must have the capacity of at least ciphertext_len
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* buffer_size must be non-zero, this function will allocate this twice + 16 bytes for tag
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* in/out must be set
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* err can be NULL in which case no messages are printed
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*/
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int gcm_decrypt(unsigned char *ciphertext, size_t ciphertext_len,
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unsigned char *key,
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unsigned char *iv,
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unsigned char *tag,
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unsigned char *plaintext)
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int gcm_decrypt(const unsigned char *key, const unsigned char *iv, size_t buffer_size,
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FILE *in, FILE *out, FILE *err
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)
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{
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EVP_CIPHER_CTX *ctx;
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int len, ret = 0;
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/* these are actually mallocd and freed */
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EVP_CIPHER_CTX *ctx = NULL;
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unsigned char *plaintext = NULL, *ciphertext = NULL;
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/* these are simply pointers into ciphertext */
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unsigned char *tag, *ciphertext_read_zone;
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int exit_code = 0, plaintext_written;
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size_t ciphertext_read;
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do {
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plaintext = malloc(buffer_size);
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if(!plaintext) {
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if(NULL != err)
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fprintf(err, "plaintext memory allocation failed\n");
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break;
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}
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ciphertext = malloc(buffer_size + GCM_TAG_LEN);
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if(!ciphertext) {
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if(NULL != err)
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fprintf(err, "ciphertext memory allocation failed\n");
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break;
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}
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tag = ciphertext;
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ciphertext_read_zone = ciphertext + GCM_TAG_LEN;
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/* there must be *at least* 16 byte gcm tag / footer */
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ciphertext_read = fread(tag, 1, GCM_TAG_LEN, in);
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if(ciphertext_read != GCM_TAG_LEN) {
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if(NULL != err)
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fprintf(err, "File too small for decryption, no footer/tag?\n");
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break;
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}
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/* Create and initialise the context */
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if(!(ctx = EVP_CIPHER_CTX_new()))
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break;
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/* Initialise the decryption operation. */
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if(!EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), NULL, NULL, NULL))
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if(1 != EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), NULL, NULL, NULL))
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break;
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/* Setting IV length is not necessary because the default of 12 bytes (96 bits) will be used
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if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, IV_LEN, NULL))
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if(1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, IV_LEN, NULL))
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break;
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*/
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/* Initialise key and IV */
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if(!EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv))
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if(1 != EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv))
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break;
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/*
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* Provide the message to be decrypted, and obtain the plaintext output.
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* EVP_DecryptUpdate can be called multiple times if necessary
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*/
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if(!EVP_DecryptUpdate(ctx, plaintext, &len, ciphertext, ciphertext_len))
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break;
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do {
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ciphertext_read = fread(ciphertext_read_zone, 1, buffer_size, in);
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/* decrypt the bytes previously saved in tag plus ones currently read except the last 16 bytes */
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if(1 != EVP_DecryptUpdate(ctx, plaintext, &plaintext_written, tag, ciphertext_read))
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goto fail;
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/* now save the unused last 16 bytes in tag */
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memcpy(tag, ciphertext_read_zone + ciphertext_read - GCM_TAG_LEN, GCM_TAG_LEN);
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if(((size_t) plaintext_written) != ciphertext_read) {
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if(NULL != err)
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fprintf(err, "plaintext_written (%d) != plaintext_read (%lu)\n", plaintext_written, (unsigned long) ciphertext_read);
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goto fail;
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}
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fwrite(plaintext, 1, plaintext_written, out);
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} while(buffer_size == ciphertext_read);
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/* Set expected tag value. Works in OpenSSL 1.0.1d and later */
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if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, GCM_TAG_LEN, tag))
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if(1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, GCM_TAG_LEN, ciphertext))
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break;
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/*
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* Finalise the decryption. A return value of 1 indicates success,
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* return value of 0 is a failure - the plaintext is not trustworthy.
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*/
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ret = EVP_DecryptFinal_ex(ctx, plaintext + len, &len);
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} while(0);
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if(1 != EVP_DecryptFinal_ex(ctx, NULL, &plaintext_written)) {
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if(NULL != err)
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fprintf(err, "integrity check failed\n");
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break;
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}
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/* success! */
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exit_code = 1;
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} while(0);
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fail:
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if(plaintext)
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free(plaintext);
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if(ciphertext)
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free(ciphertext);
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/* Clean up */
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if(ctx)
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EVP_CIPHER_CTX_free(ctx);
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return ret;
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}
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/* returns 0 on success, 1 on openssl failure, 2 on other failure */
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int pegh(char *password, int decrypt,
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uint32_t scrypt_max_mem_mb, uint32_t N,
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uint8_t r, uint8_t p)
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{
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unsigned char key[KEY_LEN] = {0};
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/* these are actually mallocd and freed */
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unsigned char *in_buffer, *out_buffer = NULL;
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/* these are simply pointers into the above */
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unsigned char *salt, *iv, *ciphertext, *plaintext, *tag;
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int exit_code = 2;
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size_t read, in_buffer_len = 0, out_buffer_len, in_buffer_allocd_size = INITIAL_BUFFER_SIZE;
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in_buffer = malloc(in_buffer_allocd_size);
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if(!in_buffer) {
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fprintf(stderr, "in_buffer memory allocation failed\n");
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return exit_code;
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if(NULL != err && exit_code != 1) {
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/* print openssl errors */
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ERR_print_errors_fp(err);
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fprintf(err, "decryption failed\n");
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}
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while ((read = fread(in_buffer + in_buffer_len, 1, BYTES_PER_READ, stdin)) > 0) {
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in_buffer_len += read;
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if ((in_buffer_len + BYTES_PER_READ) > in_buffer_allocd_size) {
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in_buffer_allocd_size = in_buffer_allocd_size * 1.5;
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in_buffer = realloc(in_buffer, in_buffer_allocd_size);
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if(!in_buffer) {
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fprintf(stderr, "in_buffer memory reallocation failed\n");
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return exit_code;
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}
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}
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}
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do {
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if (in_buffer_len <= (decrypt ? OVERHEAD_LEN : 0)) {
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fprintf(stderr, "File too small for %scryption\n", decrypt ? "de" : "en");
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break;
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}
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out_buffer_len = decrypt ? (in_buffer_len - OVERHEAD_LEN) : (in_buffer_len + OVERHEAD_LEN);
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out_buffer = malloc(out_buffer_len);
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if(!out_buffer) {
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fprintf(stderr, "out_buffer memory allocation failed\n");
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break;
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}
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if(decrypt) {
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if(in_buffer[0] != 0) {
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fprintf(stderr, "unsupported file format version %d, we only support version 0\n", in_buffer[0]);
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break;
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}
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N = ((in_buffer[1] & 0xFF) << 24)
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| ((in_buffer[2] & 0xFF) << 16)
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| ((in_buffer[3] & 0xFF) << 8)
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| (in_buffer[4] & 0xFF);
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r = in_buffer[5];
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p = in_buffer[6];
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salt = in_buffer + PRE_SALT_LEN;
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iv = salt + SALT_LEN;
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ciphertext = iv + IV_LEN;
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tag = ciphertext + out_buffer_len;
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plaintext = out_buffer;
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} else {
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out_buffer[0] = 0;
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out_buffer[1] = (N >> 24) & 0xFF;
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out_buffer[2] = (N >> 16) & 0xFF;
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out_buffer[3] = (N >> 8) & 0xFF;
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out_buffer[4] = N & 0xFF;
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out_buffer[5] = r;
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out_buffer[6] = p;
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salt = out_buffer + PRE_SALT_LEN;
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/* generate random salt+iv */
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if (RAND_bytes(salt, SALT_IV_LEN) <= 0) {
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fprintf(stderr, "random salt+iv generation error\n");
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exit_code = 1;
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break;
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}
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iv = salt + SALT_LEN;
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ciphertext = iv + IV_LEN;
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tag = ciphertext + in_buffer_len;
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||||
plaintext = in_buffer;
|
||||
}
|
||||
|
||||
/* https://commondatastorage.googleapis.com/chromium-boringssl-docs/evp.h.html#EVP_PBE_scrypt */
|
||||
if (EVP_PBE_scrypt(
|
||||
password, strlen(password),
|
||||
salt, SALT_LEN,
|
||||
(uint64_t) N, (uint64_t) r, (uint64_t) p,
|
||||
(uint64_t) scrypt_max_mem_mb * 1024 * 1024,
|
||||
key, KEY_LEN
|
||||
) <= 0) {
|
||||
fprintf(stderr, "scrypt key derivation error\n");
|
||||
exit_code = 1;
|
||||
break;
|
||||
}
|
||||
|
||||
if(decrypt) {
|
||||
if (1 != gcm_decrypt(ciphertext, out_buffer_len,
|
||||
key, iv,
|
||||
tag,
|
||||
plaintext)) {
|
||||
fprintf(stderr, "integrity check failed\n");
|
||||
exit_code = 1;
|
||||
break;
|
||||
}
|
||||
} else {
|
||||
if (1 != gcm_encrypt(plaintext, in_buffer_len,
|
||||
key, iv,
|
||||
ciphertext, tag)) {
|
||||
fprintf(stderr, "encryption failed\n");
|
||||
exit_code = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
/* success! */
|
||||
fwrite(out_buffer, 1, out_buffer_len, stdout);
|
||||
exit_code = 0;
|
||||
} while(0);
|
||||
|
||||
if(in_buffer)
|
||||
free(in_buffer);
|
||||
if(out_buffer)
|
||||
free(out_buffer);
|
||||
|
||||
/* print openssl errors */
|
||||
if(exit_code == 1)
|
||||
ERR_print_errors_fp(stderr);
|
||||
|
||||
return exit_code;
|
||||
}
|
||||
|
||||
/* returns 1 on success, 0 on error */
|
||||
int scrypt_derive_key(char *password,
|
||||
uint32_t scrypt_max_mem_mb, uint32_t N,
|
||||
uint8_t r, uint8_t p, unsigned char *salt, unsigned char *key, FILE *err) {
|
||||
/* derive key using salt, password, and scrypt parameters */
|
||||
if (EVP_PBE_scrypt(
|
||||
password, strlen(password),
|
||||
salt, SALT_LEN,
|
||||
(uint64_t) N, (uint64_t) r, (uint64_t) p,
|
||||
(uint64_t) scrypt_max_mem_mb * 1024 * 1024,
|
||||
key, KEY_LEN
|
||||
) <= 0) {
|
||||
if(NULL != err) {
|
||||
fprintf(err, "scrypt key derivation error\n");
|
||||
ERR_print_errors_fp(err);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* returns 1 on success, 0 on failure */
|
||||
int pegh_encrypt(char *password,
|
||||
uint32_t scrypt_max_mem_mb, size_t buffer_size,
|
||||
FILE *in, FILE *out, FILE *err,
|
||||
uint32_t N, uint8_t r, uint8_t p)
|
||||
{
|
||||
unsigned char key[KEY_LEN] = {0}, salt[SALT_IV_LEN] = {0};
|
||||
/* this is simply a pointer into salt */
|
||||
const unsigned char *iv = salt + SALT_LEN;
|
||||
|
||||
/* first write the version and parameters */
|
||||
salt[0] = 0;
|
||||
salt[1] = (N >> 24) & 0xFF;
|
||||
salt[2] = (N >> 16) & 0xFF;
|
||||
salt[3] = (N >> 8) & 0xFF;
|
||||
salt[4] = N & 0xFF;
|
||||
salt[5] = r;
|
||||
salt[6] = p;
|
||||
fwrite(salt, 1, PRE_SALT_LEN, out);
|
||||
|
||||
/* generate random salt+iv, then write it out */
|
||||
if (RAND_bytes(salt, SALT_IV_LEN) <= 0) {
|
||||
if(NULL != err) {
|
||||
fprintf(err, "random salt+iv generation error\n");
|
||||
ERR_print_errors_fp(err);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
fwrite(salt, 1, SALT_IV_LEN, out);
|
||||
|
||||
if(1 != scrypt_derive_key(password, scrypt_max_mem_mb, N, r, p, salt, key, err))
|
||||
return 0;
|
||||
|
||||
return gcm_encrypt(key, iv, buffer_size, in, out, err);
|
||||
}
|
||||
|
||||
/* returns 1 on success, 0 on failure */
|
||||
int pegh_decrypt(char *password,
|
||||
uint32_t scrypt_max_mem_mb, size_t buffer_size,
|
||||
FILE *in, FILE *out, FILE *err)
|
||||
{
|
||||
unsigned char key[KEY_LEN] = {0}, salt[SALT_IV_LEN] = {0};
|
||||
/* this is simply a pointer into salt */
|
||||
const unsigned char *iv = salt + SALT_LEN;
|
||||
|
||||
size_t header_read;
|
||||
|
||||
uint32_t N;
|
||||
uint8_t r, p;
|
||||
|
||||
/* first read the version and parameters */
|
||||
header_read = fread(salt, 1, PRE_SALT_LEN, in);
|
||||
if(header_read != PRE_SALT_LEN) {
|
||||
if(NULL != err)
|
||||
fprintf(err, "File too small for decryption, invalid header?\n");
|
||||
return 0;
|
||||
}
|
||||
if(salt[0] != 0) {
|
||||
if(NULL != err)
|
||||
fprintf(err, "unsupported file format version %d, we only support version 0\n", salt[0]);
|
||||
return 0;
|
||||
}
|
||||
N = ((salt[1] & 0xFF) << 24)
|
||||
| ((salt[2] & 0xFF) << 16)
|
||||
| ((salt[3] & 0xFF) << 8)
|
||||
| (salt[4] & 0xFF);
|
||||
r = salt[5];
|
||||
p = salt[6];
|
||||
|
||||
/* next read salt+iv */
|
||||
header_read = fread(salt, 1, SALT_IV_LEN, in);
|
||||
if(header_read != SALT_IV_LEN) {
|
||||
if(NULL != err)
|
||||
fprintf(err, "File too small for decryption, invalid header?\n");
|
||||
return 0;
|
||||
}
|
||||
|
||||
if(1 != scrypt_derive_key(password, scrypt_max_mem_mb, N, r, p, salt, key, err))
|
||||
return 0;
|
||||
|
||||
return gcm_decrypt(key, iv, buffer_size, in, out, err);
|
||||
}
|
||||
|
||||
int help(int exit_code) {
|
||||
/* this ridiculous split is because C89 only supports strings of 509 characters */
|
||||
fprintf(stderr, "\
|
||||
usage: pegh [-demNrpshV] password\n\
|
||||
-e encrypt stdin to stdout, default mode\n\
|
||||
-d decrypt stdin to stdout\n\
|
||||
usage: pegh [options...] password\n\
|
||||
-e encrypt input to output, default mode\n\
|
||||
-d decrypt input to output\n\
|
||||
-i <filename> file to use for input, default stdin\n\
|
||||
-o <filename> file to use for output, if set and there is an error and append\n\
|
||||
is not set, we try to delete this file before exiting,\n");
|
||||
fprintf(stderr, "\
|
||||
default stdout\n\
|
||||
-a append to -o instead of truncate\n\
|
||||
-b <max_mb> maximum megabytes of ram to use per read/write buffer, so while\n\
|
||||
decrypting/encrypting twice this will be used, but these are\n");
|
||||
fprintf(stderr, "\
|
||||
only allocated after scrypt is finished so max usage will be\n\
|
||||
the highest of these only, not both combined, default: %d\n\
|
||||
-m <max_mb> maximum megabytes of ram to use when deriving key from password\n\
|
||||
with scrypt, applies for encryption AND decryption, must\n\
|
||||
almost linearly scale with -N, if too low operation will fail,\n\
|
||||
default: %d\n", SCRYPT_MAX_MEM_MB);
|
||||
default: %d\n", BUFFER_SIZE_MB, SCRYPT_MAX_MEM_MB);
|
||||
fprintf(stderr, "\
|
||||
-N <num> scrypt parameter N, only applies for encryption, default %d\n\
|
||||
this is rounded up to the next highest power of 2\n\
|
||||
@ -362,6 +454,7 @@ usage: pegh [-demNrpshV] password\n\
|
||||
BEWARE: -s 32 requires 2G ram, -s 64 requires 4G and so on,\n\
|
||||
default: 1\n\
|
||||
-h print this usage text\n\
|
||||
-q do not print error output to stderr\n\
|
||||
-V show version number and format version support then quit\n\
|
||||
\nFor additional info on scrypt params refer to:\n\
|
||||
https://blog.filippo.io/the-scrypt-parameters/\n\
|
||||
@ -410,11 +503,14 @@ uint32_t next_highest_power_of_2(uint32_t v) {
|
||||
/* returns 0 on success, 1 on openssl failure, 2 on other failure */
|
||||
int main(int argc, char **argv)
|
||||
{
|
||||
int optind, decrypt = 0;
|
||||
int optind, decrypt = 0, append = 0, exit_code = 2;
|
||||
char *password = NULL;
|
||||
uint32_t N = SCRYPT_N, scrypt_max_mem_mb = SCRYPT_MAX_MEM_MB, scale = 1;
|
||||
uint32_t N = SCRYPT_N, scrypt_max_mem_mb = SCRYPT_MAX_MEM_MB, buffer_size_mb = BUFFER_SIZE_MB, scale = 1;
|
||||
uint8_t r = SCRYPT_R, p = SCRYPT_P;
|
||||
|
||||
FILE *in = stdin, *out = stdout, *err = stderr;
|
||||
char *in_filename = NULL, *out_filename = NULL;
|
||||
|
||||
for (optind = 1; optind < argc; ++optind) {
|
||||
if(strlen(argv[optind]) == 2 && argv[optind][0] == '-') {
|
||||
|
||||
@ -431,6 +527,26 @@ int main(int argc, char **argv)
|
||||
case 'd':
|
||||
decrypt = 1;
|
||||
break;
|
||||
case 'a':
|
||||
append = 1;
|
||||
break;
|
||||
case 'i':
|
||||
if(++optind >= argc) {
|
||||
fprintf(stderr, "Error: %s requires an argument\n", argv[optind - 1]);
|
||||
return help(2);
|
||||
}
|
||||
in_filename = argv[optind];
|
||||
break;
|
||||
case 'o':
|
||||
if(++optind >= argc) {
|
||||
fprintf(stderr, "Error: %s requires an argument\n", argv[optind - 1]);
|
||||
return help(2);
|
||||
}
|
||||
out_filename = argv[optind];
|
||||
break;
|
||||
case 'b':
|
||||
buffer_size_mb = parse_int_arg(++optind, argc, argv);
|
||||
break;
|
||||
case 'm':
|
||||
scrypt_max_mem_mb = parse_int_arg(++optind, argc, argv);
|
||||
break;
|
||||
@ -446,6 +562,9 @@ int main(int argc, char **argv)
|
||||
case 'p':
|
||||
p = parse_byte_arg(++optind, argc, argv);
|
||||
break;
|
||||
case 'q':
|
||||
err = NULL;
|
||||
break;
|
||||
case 'V':
|
||||
fprintf(stderr, "pegh %s\nformat versions supported: 0\n", PEGH_VERSION);
|
||||
return 0;
|
||||
@ -453,25 +572,25 @@ int main(int argc, char **argv)
|
||||
return help(0);
|
||||
default:
|
||||
fprintf(stderr, "Error: invalid option %s\n", argv[optind]);
|
||||
return help(2);
|
||||
return help(exit_code);
|
||||
}
|
||||
} else if (password == NULL) {
|
||||
password = argv[optind];
|
||||
} else {
|
||||
fprintf (stderr, "Error: more than one password provided\n");
|
||||
return help(2);
|
||||
return help(exit_code);
|
||||
}
|
||||
}
|
||||
|
||||
if(password == NULL) {
|
||||
if(argc == optind) {
|
||||
fprintf (stderr, "Error: no password provided\n");
|
||||
return help(2);
|
||||
return help(exit_code);
|
||||
}
|
||||
|
||||
if((argc - optind) != 1) {
|
||||
fprintf (stderr, "Error: more than one password provided\n");
|
||||
return help(2);
|
||||
return help(exit_code);
|
||||
}
|
||||
password = argv[optind];
|
||||
}
|
||||
@ -486,5 +605,37 @@ int main(int argc, char **argv)
|
||||
return 0;
|
||||
*/
|
||||
|
||||
return pegh(password, decrypt, scrypt_max_mem_mb, N, r, p);
|
||||
if(NULL != in_filename) {
|
||||
in = fopen(in_filename, "rb");
|
||||
if(!in) {
|
||||
fprintf (stderr, "Error: file '%s' cannot be opened for reading\n", in_filename);
|
||||
return exit_code;
|
||||
}
|
||||
}
|
||||
if(NULL != out_filename) {
|
||||
out = fopen(out_filename, append ? "ab" : "wb");
|
||||
if(!out) {
|
||||
fprintf (stderr, "Error: file '%s' cannot be opened for writing\n", out_filename);
|
||||
if(NULL != in_filename)
|
||||
fclose(in);
|
||||
return exit_code;
|
||||
}
|
||||
}
|
||||
|
||||
if(decrypt)
|
||||
exit_code = pegh_decrypt(password, scrypt_max_mem_mb, 1024 * 1024 * buffer_size_mb, in, out, err);
|
||||
else
|
||||
exit_code = pegh_encrypt(password, scrypt_max_mem_mb, 1024 * 1024 * buffer_size_mb, in, out, err, N, r, p);
|
||||
|
||||
if(NULL != in_filename)
|
||||
fclose(in);
|
||||
if(NULL != out_filename) {
|
||||
fclose(out);
|
||||
/* attempt to stop programs from using incomplete/bad data */
|
||||
if(exit_code != 1 && !append)
|
||||
remove(out_filename);
|
||||
}
|
||||
|
||||
/* to the OS, 0 means success, the above functions 1 means success */
|
||||
return exit_code == 1 ? 0 : 1;
|
||||
}
|
||||
|
37
test.sh
37
test.sh
@ -1,20 +1,45 @@
|
||||
#!/bin/bash
|
||||
|
||||
set -euo pipefail
|
||||
|
||||
# try different size files to encrypt/decrypt
|
||||
[ -e /dev/shm/randombytes ] || dd if=/dev/urandom bs=1M count=100 of=/dev/shm/randombytes
|
||||
|
||||
# compile C and rust code this way
|
||||
gcc pegh.c -lcrypto -O3 -o pegh
|
||||
# try make if it's installed, otherwise fall back to cc
|
||||
make || cc pegh.c -lcrypto -O3 -o pegh
|
||||
#cargo build --release
|
||||
|
||||
export key=$(openssl rand -base64 20)
|
||||
export key="$(openssl rand -base64 20)"
|
||||
|
||||
echo "key: $key"
|
||||
|
||||
test () {
|
||||
bin=$1
|
||||
tee >(md5sum 1>&2) < /dev/shm/randombytes | $bin -e $key | $bin -d $key | md5sum 1>&2
|
||||
#$bin -e $key < /dev/shm/randombytes | $bin -d $key &>/dev/null
|
||||
bin="$1"
|
||||
|
||||
echo 'encrypting then decrypting with the same key should succeed'
|
||||
"$bin" -e "$key" < /dev/shm/randombytes | "$bin" -d "$key" | cmp - /dev/shm/randombytes
|
||||
|
||||
echo 'test with -s 32 requiring 2gb of ram should succeed'
|
||||
# can send -s 32 or -m 2048 to decrypt command with identical effect
|
||||
"$bin" -e "$key" -s 32 < /dev/shm/randombytes | "$bin" -d "$key" -m 2048 | cmp - /dev/shm/randombytes
|
||||
|
||||
set +e
|
||||
# these should fail
|
||||
echo 'encrypting with one key and decrypting with another should fail'
|
||||
"$bin" -e "$key" -i /dev/shm/randombytes | "$bin" -d "$key-wrongkey" | cmp - /dev/shm/randombytes && echo "ERROR: appending -wrongkey to key somehow still worked" && exit 1
|
||||
|
||||
echo 'large values of N without enough memory should fail'
|
||||
"$bin" -e "$key" -N 2000000 -i /dev/shm/randombytes >/dev/null && echo "ERROR: N of 2 million without extra memory worked" && exit 1
|
||||
"$bin" -d "$key" -N 2000000 -i /dev/shm/randombytes >/dev/null && echo "ERROR: N of 2 million without extra memory worked" && exit 1
|
||||
|
||||
# todo: can we also make this the case for stdout? needs some buffering...
|
||||
echo 'bad decryption should result in output file being deleted'
|
||||
echo 'hopefully this doesnt make it to disk' | "$bin" "$key" | cat - <(echo -n a) | "$bin" -d "$key" -o bla.txt && exit 1
|
||||
[ -e bla.txt ] && echo "ERROR: bla.txt should not exist" && exit 1
|
||||
set -e
|
||||
}
|
||||
|
||||
time test ./pegh
|
||||
|
||||
echo "successful test run!"
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user