RSA_private_decrypt failed - c

I use openssl. First off I created private/public keys, then I encrypt a string and keep the result in a file. When I try to decrypt the file my program fails. What's more, the encrypted file is different each time(I use md5sum checked). What have I missed to deal with?
/*
gcc -lssl queation.c -o test_ssl
#openssl genrsa -out test_private.key 1024
#openssl rsa -in test_private.key -pubout -out test_public.key
*/
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<openssl/rsa.h>
#include<openssl/pem.h>
#include<openssl/err.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <linux/netdevice.h>
#include <linux/sockios.h>
#include <linux/if.h>
#include <asm/types.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <net/if_arp.h>
#include <netinet/if_ether.h>
#include <netinet/ether.h>
#include <fcntl.h>
#include <sys/socket.h>
#define OPENSSLKEY "test_private.key"
#define PUBLICKEY "test_public.key"
#define BUFFSIZE 1024
#define SIZE 1024
#define LIC_FILE "lic.rn"
#define PRTFL printf("fun = %s, line = %d\n", __FUNCTION__,__LINE__)
static char *ptr_en;
static char *p_en;
static RSA *p_rsa_public;
static FILE *fp_public;
static int flen_public, rsa_public_len;
static char *ptr_de;
static char *p_de;
static RSA *p_rsa_private;
static FILE *fp_private;
static int flen_private, rsa_private_len;
void usage( unsigned char * prog_name)
{
printf("usage: %s\n",
prog_name);
exit(1);
}
int main(int argc , char ** argv)
{
int i, ret , len;
unsigned char buf_plain[32];
unsigned char *buf_en;
unsigned char *raw_buffer;
FILE * pf_tmp;
if( argc != 1)
{
usage(argv[0]);
}
snprintf(buf_plain,sizeof(buf_plain),"this is a test line.\n");
if((fp_public=fopen(PUBLICKEY,"r"))==NULL)
{
perror("open public key file error");
ret = -1;
goto error;
}
if((p_rsa_public = PEM_read_RSA_PUBKEY(fp_public,NULL,NULL,NULL))==NULL)
{
ERR_print_errors_fp(stdout);
ret = -1;
goto error;
}
rsa_public_len=RSA_size(p_rsa_public);
p_en=(unsigned char *)malloc(rsa_public_len+1);
memset(p_en,0,rsa_public_len+1);
//printf("%s(%d)p_en = %p,rsa_public_len = %d\n", __FUNCTION__,__LINE__,p_en,rsa_public_len);
len = RSA_public_encrypt(rsa_public_len,buf_plain,p_en,p_rsa_public,RSA_NO_PADDING);
if (len !=rsa_public_len)
{
fprintf(stderr,"Error: len =%d, rsa_public_len = %d,ciphertext should match length of key\n", len,rsa_public_len);
ret = -1;
goto error;
}
pf_tmp = fopen(LIC_FILE,"w");
if( NULL == pf_tmp )
{
printf("open %s failed\n",LIC_FILE);
ret = -1;
goto error;
}
fwrite(p_en,1,128,pf_tmp);
fclose(pf_tmp);
if((fp_private=fopen(OPENSSLKEY,"r"))==NULL)
{
perror("open private key file error");
ret = -1;
goto error;
}
if((p_rsa_private=PEM_read_RSAPrivateKey(fp_private,NULL,NULL,NULL))==NULL)
{
ERR_print_errors_fp(stdout);
ret = -1;
goto error;
}
rsa_private_len = RSA_size(p_rsa_private);
pf_tmp = fopen(LIC_FILE,"r");
if( NULL == pf_tmp )
{
printf("open %s failed\n",LIC_FILE);
ret = -1;
goto error2;
}
raw_buffer = calloc(rsa_private_len,sizeof(char));
if( NULL == raw_buffer )
{
ret = -1;
goto error;
}
len = fread(raw_buffer, sizeof(char),sizeof(raw_buffer), pf_tmp);
if( len <=0 )
{
ret = -1;
goto error;
}
p_de=(unsigned char *)malloc(rsa_private_len+1);
memset(p_de,0,rsa_private_len+1);
//printf("%s(%d)p_en = %p,rsa_public_len = %d\n", __FUNCTION__,__LINE__,p_en,rsa_public_len);
len =RSA_private_decrypt (rsa_private_len,raw_buffer,p_de,p_rsa_private,RSA_NO_PADDING);
printf("%s(%d) p_de = %s\n",__FUNCTION__,__LINE__,p_de);
if ( len != rsa_private_len )
{
fprintf(stderr,"Error: ciphertext should match length of key\n");
exit(1);
}
error2:
fclose(pf_tmp);
error:
free(ptr_en);
free(ptr_de);
fclose(fp_public);
fclose(fp_private);
RSA_free(p_rsa_public);
RSA_free(p_rsa_private);
return ret;
}

It looks like you are not reading the whole file:
len = fread(raw_buffer, sizeof(char),sizeof(raw_buffer), pf_tmp);
Note that sizeof(raw_buffer) is the size of a pointer, but you wrote 128 bytes into the file (1024 bits). So you're only reading back 4 or 8 bytes and trying to decrypt that.
Try reading 128 bytes back.

Related

Create file recursive in C Linux

I want to create file test in this path /tmp/a1/a2/a3/a4/test
But all the directories (a1..a4) doesn't exist, How can I create this file in C at Linux OS?
You can use the mkdir function from sys/stat.h to create the directories as you need them. E.g.,
mkdir("/tmp/a1",0766);
However, you should check, via stat, whether or not the directories exist already.
Once you've created the directory structure, your file can be created with
open("/tmp/a1/a2/a3/a4/test",O_WRONLY|O_CREAT);
Obviously, you need to check the return values of all of these function calls.
Below is a complete function in C that achieves what you want.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
#include <fcntl.h>
int create_file_with_parent_dirs (char pathname[])
{
for (char *p = pathname; (p = strchr(p ,'/')) != NULL; ++p) {
char c = p[1];
p[1] = '\0';
errno = 0;
if (mkdir(pathname, 0700) != 0 && errno != EEXIST) {
perror("mkdir");
return -1;
}
p[1] = c;
}
int fd = creat(pathname, 0600);
if (fd < 0)
perror("creat");
return fd;
}
int main (void)
{
char pathname[] = "/tmp/a1/a2/a3/a4/test";
create_file_with_parent_dirs(pathname);
}
Note that the array pointed to by pathname must be modifiable. Do not call the function with a string literal. Also beware that the file will be truncated to zero length if it already exists.
You can use this code. This program split the path and check whether the path exist or not if not create the path and create the final path as file.
#include <dirent.h>
#include <errno.h>
#include <bits/stdc++.h>
#include <iostream>
#include <sys/stat.h>
#include <sys/types.h>
#include <vector>
#include <fstream>
using namespace std;
int checkDir(char * path)
{
DIR* dir = opendir(path);
if (dir) {
/* Directory exists. */
closedir(dir);
return 0;
} else if (ENOENT == errno) {
/* Directory does not exist. */
return -1;
} else {
/* opendir() failed for some other reason. */
return -2;
}
}
int make_dir(char *path)
{
int ret = checkDir(path);
if( ret == -1)
{
if (mkdir(path, 0777) == -1)
{
cerr << "Error : " << strerror(errno) << endl;
return -1;
}
else
{
cout << "Directory created";
return 0;
}
}
return ret;
}
int main(int args, char **argv)
{
std::string strpath(argv[1]);
std::string delimeter = "/";
std::string substr1 = "";
int cnt = 0;
std::vector<string> strPaths;
std::string strbck = strpath;
for( int i = strpath.find(delimeter); i != std::string::npos; i = strpath.find(delimeter))
{
if(cnt > 0)
{
substr1 = strbck.substr(0, substr1.length() + i + 1);
strPaths.push_back(substr1);
}
strpath = strpath.substr(i +1,strpath.length());
cnt++;
}
strPaths.push_back(strbck);
std::string str;
for_each( strPaths.begin() ,strPaths.end() -1 , [](std::string str) {make_dir((char*)str.c_str());});
ofstream outfile;
std::ofstream file {strPaths[strPaths.size() -1].c_str() };
file << "hello"<< std::endl;
file.close();
return 0;
}

RSA_verify() causes segmentation fault

Teh function below causes a segmentation fault when it gets to the RSA_verify() part. I'm a c-beginner so it's hard for me to find the reason for the problem. Maybe someone can point out what I'm doing wrong. It would be very helpful, thanks in advance.
Here's the Code:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <openssl/sha.h>
#include <openssl/dsa.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/pem.h>
#include <openssl/rsa.h>
#include <openssl/bio.h>
#define BUF 20000
#define DSS 20
int matchCipherToSign(unsigned char *signPath, char *cipherPath) {
unsigned char *bufCipher = malloc(BUF);
unsigned char *sha = malloc(SHA_DIGEST_LENGTH);
unsigned char *bufSign = malloc(BUF);
unsigned int retSign;
int ret=0;
int retCipher;
FILE *key;
RSA *rsa = RSA_new();
EVP_MD_CTX ctx;
key = fopen("key.bin", "rb");
if (key == NULL){
printf("Couldn't open file key.bin.\n");
exit(EXIT_FAILURE);
}
retSign = readFile(signPath, bufSign);
if (retSign == 0){
printf("Couldn't read file %s.\n", signPath);
exit(EXIT_FAILURE);
}
retCipher = readFile(cipherPath, bufCipher);
if (retCipher == 0){
printf("Couldn't open file %s.\n", cipherPath);
exit(EXIT_FAILURE);
}
rsa = PEM_read_RSA_PUBKEY(key, &rsa, NULL, NULL);
fclose(key);
if (1!=EVP_DigestInit(&ctx, EVP_sha1())) {
printf("EVP_DigestInit Error.\n");
exit(EXIT_FAILURE);
}
if (1!=EVP_DigestUpdate(&ctx, bufCipher, retCipher)) {
printf("VP_DigestUpdate Error.\n");
exit(EXIT_FAILURE);
}
if (1!=EVP_DigestFinal(&ctx, sha, NULL)) {
printf("EVP_DigestFinal Error.\n");
exit(EXIT_FAILURE);
}
ret = RSA_verify(NID_sha1, sha, SHA_DIGEST_LENGTH, bufSign, sizeof(bufSign), rsa);
RSA_free(rsa);
free(bufCipher);
free(bufSign);
free(sha);
return ret;
}
Thanks for your help!

PulseAudio:sound recorded but plays annoying sound

I'm new with PulseAudio. I'm trying to make simple programs. One would record the sound and save it in baniry file, and the other one should open it and play. Here is my code for recording:
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <pulse/simple.h>
#include <pulse/error.h>
#define BUFSIZE 32
int main(int argc, char*argv[])
{
/* The Sample format to use */
static const pa_sample_spec ss = {
.format = PA_SAMPLE_S16LE, //16bit iqneba agwerili tito sample
.rate = 44100, //number of samples played in each second
.channels = 2
};
pa_simple *s_in = NULL;
int ret = 1;
int error;
int siri =0;
//file info
FILE* pFile;
char* yourFilePath = "xma.bin";
pFile = fopen(yourFilePath,"wb");
if (!(s_in = pa_simple_new(NULL, argv[0], PA_STREAM_RECORD, NULL, "record", &ss, NULL, NULL, &error)))
{
fprintf(stderr, __FILE__": pa_simple_new() failed: %s\n", pa_strerror(error));
goto finish;
}
for (;siri<10000;siri+=1)
{
uint8_t buf[BUFSIZE];
ssize_t r;
int yorBufferSize = strlen(buf) + 1;
/* Write your buffer to disk. */
if (pa_simple_read(s_in, buf, sizeof(buf), &error) < 0)
{
fprintf(stderr, __FILE__": read() failed: %s\n", strerror(errno));
goto finish;
}
if (pFile)
{
fwrite(buf, yorBufferSize, 1, pFile);
puts("Wrote to file!");
}
else
{
puts("Something wrong writing to File.");
}
}
ret = 0;
finish:
if (s_in)
pa_simple_free(s_in);
return ret;
fclose(pFile);
}
And here is my recording program:
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <pulse/simple.h>
#include <pulse/error.h>
#define BUFSIZE 32
int main(int argc, char*argv[])
{
/* The Sample format to use */
static const pa_sample_spec ss = {
.format = PA_SAMPLE_S16LE, //16bit iqneba agwerili tito sample
.rate = 44100, //number of samples played in each second
.channels = 2
};
pa_simple *s_out = NULL;
int ret = 1;
int error;
//file info
FILE* pFile;
char* yourFilePath = "xma.bin";
pFile = fopen(yourFilePath, "rb");
/* Create a new playback stream */
if (!(s_out = pa_simple_new(NULL, argv[0], PA_STREAM_PLAYBACK, NULL, "playback", &ss, NULL, NULL, &error)))
{
fprintf(stderr, __FILE__": pa_simple_new() failed: %s\n", pa_strerror(error));
goto finish;
}
for (;;)
{
uint8_t buf[BUFSIZE];
fread(buf, sizeof(buf), 1, pFile);
ssize_t r;
if(feof(pFile))
{
break;
}
printf("%x", buf);
/* ... and play it */
if (pa_simple_write(s_out, buf, sizeof(buf), &error) < 0)
{
fprintf(stderr, __FILE__": pa_simple_write() failed: %s\n", pa_strerror(error));
goto finish;
}
}
/* Make sure that every single sample was played */
if (pa_simple_drain(s_out, &error) < 0)
{
fprintf(stderr, __FILE__": pa_simple_drain() failed: %s\n", pa_strerror(error));
goto finish;
}
ret = 0;
finish:
if (s_out)
pa_simple_free(s_out);
return ret;
fclose(pFile);
}
For loop in record program is just for time to record something(could not figure out how to set a timer) and I know that I should not use gotos but its for educational purposes(example provided on PulseAudio website). I tried hexdump of xma.bin and it gave me totally different ouput
than printf("%x", buf); Basically printf only gives back bf9fe15c repeatedly and it make annoying sound. Hope you can help. thanks.
I deleted pa_simple_drain() (it was my mistake that i used this function in recording program)function from record program and now it works. But in printf("%x", buf) it still gives me back same hex value over and over again. But programs work great. Can someone exmplain why does it print same value?

HMAC using Linux Kernel Crypto APIs not the same as the one by OpenSSL command

I tried code(Using Linux Kernel Crypto APIs) for calculating HMAC-SHA512 on a file.
Surprisingly, HMAC calculated from the kernel code and from OpenSSL commands are different.
OpenSSL commands are:
openssl rand -base64 16
plakOhrXlfnBENPVBo91kg==
openssl dgst -sha512 -mac hmac -macopt key:plakOhrXlfnBENPVBo91kg== ../hello6.ko
HMAC-SHA512(../hello6.ko)= 9605f40851630f5b7a18fa30c7e5d6f1e77afb011d319efa515556d12ba6930f459825b3695a0d0d910a714724c0d99b36ccea5c878962b32a8de65dcbcc247d
HMAC-SHA512 from the kernel code is:
84306723b713379aa666fe9aa75af3192a9707d19136c25dd2286c5f6d86dfd8f76ceaa0ce147b53c0e9f7bfab485f38f5139c687c34c840db7f7fa9438bf8b0d8df8e770088ffffc8de8e770088ffffc3f027a0ffffffff672c00000088fffff0de8e770088ffff1900000000000080672c000000000000e8de8e770088ffff
How come these HMACs are different for the same content? Any pointers to get rid of this issue is very helpful.
Base64 encoded key is generated by below command and stored in a file:
openssl rand -base64 -out $Module_name.sha512key 16
HMAC is generated on a file and stored in a file.
openssl dgst -sha512 -mac hmac -macopt key:$HMAC_KEY $HMAC_PATH/$Module_name> temp.txt
Key and File content are read by below code:
static char hmac[HMAC_SHA512_SIZE];
const char *kofilename = "/home/sri/Documents/Hello/hello6.ko";
const char *hmackey_file = "/home/sri/Documents/Hello/hello6.ko.sha512key";
const char *hmac_file = "/home/sri/Documents/Hello/hello6.ko.sha512";
unsigned char *data = NULL;
int readkostatus;
int readkeystatus;
int readhmacstatus;
unsigned char *hmackey = NULL;
unsigned char *stored_hmac = NULL;
readkeystatus = read_file(hmackey_file, &hmackey);
if(readkeystatus < 0)
goto readkeyerr;
printk(KERN_INFO "HMAC Key is :%s", hmackey);
readkostatus = read_kofile(kofilename, &data);
if(readkostatus < 0)
goto readkoerr;
printk(KERN_INFO "File data size is :%ld", strlen(data));
printk(KERN_INFO "File data is :%s", data);
hmac_sha512(hmackey, data, hmac, sizeof(hmac));
printk(KERN_INFO "FINAL HMAC:%s", hmac);
readhmacstatus = read_file(hmac_file, &stored_hmac);
if(readhmacstatus < 0)
goto readhmacerr;
printk(KERN_INFO "Stored HMAC:%s", stored_hmac);
if(!memcmp(stored_hmac, hmac, HMAC_SHA512_SIZE))
printk(KERN_INFO "HMACs match");
else
printk(KERN_INFO "HMACs do not match");
vfree(stored_hmac);
vfree(data);
vfree(hmackey);
return 0;
readkeyerr:
{
printk(KERN_INFO "hmac key read error:%d", readkeystatus);
return readkeystatus;
}
readkoerr:
{
printk(KERN_INFO "ko read error:%d", readkostatus);
return readkostatus;
}
readhmacerr:
{
printk(KERN_INFO "hmac read error:%d", readhmacstatus);
return readhmacstatus;
}
Code for reading the files is given below:
int read_file(const char *filename, unsigned char **data)
{
struct file* filp = NULL;
long filesize;
int ret = 0;
mm_segment_t old_fs = get_fs();
set_fs(get_ds());
filp = filp_open(filename, O_RDONLY, 0);
if(IS_ERR(filp)) {
ret = PTR_ERR(filp);
printk(KERN_INFO "kofile is not opened");
}
else
{
loff_t offset;
offset = 0;
filesize = filp->f_dentry->d_inode->i_size;
if (filesize <= 0 || filesize > 131072)
{
goto fileoperror;
}
*data = (unsigned char *)vmalloc(filesize);
if (*data == NULL)
goto datanull;
ret = vfs_read(filp, *data, filesize, &offset);
if(ret != filesize)
goto read_error;
filp_close(filp, NULL);
}
set_fs(old_fs);
return ret;
fileoperror:
{
filp_close(filp, NULL);
set_fs(old_fs);
printk(KERN_INFO "Invalid file operation '%s'\n", filename);
return (-EPERM);
}
datanull:
{
filp_close(filp, NULL);
set_fs(old_fs);
printk(KERN_INFO "Data Buffer is not allocated");
return (-EFAULT);
}
read_error:
{
filp_close(filp, NULL);
set_fs(old_fs);
printk(KERN_INFO "Failed to read '%s'.\n", filename);
return (-EFBIG);
}
}
int read_kofile(const char* filename, unsigned char **data)
{
return read_file(filename, data);
}
HMAC-SHA-512 is calculated on the file by calling Crypto APIs:
#define HMAC_SHA512_SIZE 64
struct hmac_sha512_result {
struct completion completion;
int err;
};
static void hmac_sha512_complete(struct crypto_async_request *req, int err) {
struct hmac_sha512_result *r=req->data;
if(err==-EINPROGRESS)
return;
r->err=err;
complete(&r->completion);
}
int hmac_sha512(const unsigned char *key, // key
const unsigned char *data_in, // data in
unsigned char *hash_out, size_t outlen) { // hash buffer and length
int rc=0;
struct crypto_ahash *tfm;
struct scatterlist sg;
struct ahash_request *req;
struct hmac_sha512_result tresult;
void *hash_buf;
size_t klen = strlen(key);
size_t dlen = strlen(data_in);
int len = HMAC_SHA512_SIZE;
char hash_tmp[HMAC_SHA512_SIZE];
char *hash_res = hash_tmp;
printk(KERN_INFO "hmac_sha512: HMAC key is %s ", key);
/* Set hash output to 0 initially */
memset(hash_out, 0, outlen);
init_completion(&tresult.completion);
tfm=crypto_alloc_ahash("hmac(sha512)",0,0);
if(IS_ERR(tfm)) {
printk(KERN_ERR "hmac_sha512: crypto_alloc_ahash failed.\n");
rc=PTR_ERR(tfm);
goto err_tfm;
}
if(!(req=ahash_request_alloc(tfm,GFP_KERNEL))) {
printk(KERN_ERR "hmac_sha512: failed to allocate request for hmac(sha512)\n");
rc=-ENOMEM;
goto err_req;
}
if(crypto_ahash_digestsize(tfm)>len) {
printk(KERN_ERR "hmac_sha512: tfm size > result buffer.\n");
rc=-EINVAL;
goto err_req;
}
ahash_request_set_callback(req,CRYPTO_TFM_REQ_MAY_BACKLOG,
hmac_sha512_complete,&tresult);
if(!(hash_buf=kzalloc(dlen,GFP_KERNEL))) {
printk(KERN_ERR "hmac_sha512: failed to kzalloc hash_buf");
rc=-ENOMEM;
goto err_hash_buf;
}
memcpy(hash_buf,data_in,dlen);
sg_init_one(&sg,hash_buf,dlen);
crypto_ahash_clear_flags(tfm,-0);
if((rc=crypto_ahash_setkey(tfm,key,klen))){
printk(KERN_ERR "hmac_sha512: crypto_ahash_setkey failed\n");
goto err_setkey;
}
ahash_request_set_crypt(req,&sg,hash_res,dlen);
rc=crypto_ahash_digest(req);
switch(rc) {
case 0:
while (len--) {
snprintf(hash_out, outlen, "%02x", (*hash_res++ & 0x0FF));
hash_out += 2;
}
break;
case -EINPROGRESS:
case -EBUSY:
rc=wait_for_completion_interruptible(&tresult.completion);
if(!rc && !(rc=tresult.err)) {
INIT_COMPLETION(tresult.completion);
break;
} else {
printk(KERN_ERR "hmac_sha512: wait_for_completion_interruptible failed\n");
goto out;
}
default:
goto out;
}
out:
err_setkey:
kfree(hash_buf);
err_hash_buf:
ahash_request_free(req);
err_req:
crypto_free_ahash(tfm);
err_tfm:
return rc;
}
Please let me know, if something is missing.
crypto_req_done defined in hash.h
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/dmi.h>
#include <linux/gfp.h>
#include <linux/msi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>
#include <linux/libata.h>
#include <linux/ahci-remap.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <net/sock.h>
#include <linux/fs.h>
#include <asm/segment.h>
#include <linux/buffer_head.h>
#include <linux/libata.h>
#include <asm/uaccess.h>
#include <asm/traps.h>
#include <linux/cdev.h>
#include <linux/kthread.h>
#include <linux/delay.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/kthread.h>
#include <linux/hashtable.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/signal_types.h>
#include <linux/fcntl.h>
#include <linux/fs.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/crypto.h>
#define MIN(a,b) (((a)<(b))?(a):(b))
#define MAX(a,b) (((a)>(b))?(a):(b))
#define TESTMGR_POISON_BYTE 0xfe
static int do_ahash_op(int (*op)(struct ahash_request *req), struct ahash_request *req, struct crypto_wait *wait)
{
int err;
err = op(req);
return crypto_wait_req(err, wait);
}
static int check_nonfinal_ahash_op(const char *op, int err){
if(err < 0){
pr_err("alg: ahash: %s() failed with err %d on test vector %s\n", op, err, get_error(err));
return 1;
}
return 0;
}
now hmac_sha256:
int hmac_sha256(unsigned char *key, size_t key_size, unsigned char *ikm, size_t ikm_len, unsigned char *okm, size_t okm_len){
int rc, key_is_null;
struct crypto_ahash *tfm;
struct ahash_request *req;
struct scatterlist pending_sgl;
DECLARE_CRYPTO_WAIT(wait);
if(key == NULL){
key = kzalloc(32, GFP_KERNEL);
key_size = 32;
key_is_null = 1;
}else{key_is_null = 0;}
tfm = crypto_alloc_ahash("hmac(sha256)", 0, 0);
if(IS_ERR(tfm)) {
rc=PTR_ERR(tfm);
printk(KERN_ERR "hmac_sha256: crypto_alloc_ahash failed(%s).\n", get_error(rc));
goto err_tfm;
}
if(!(req = ahash_request_alloc(tfm, GFP_KERNEL))) {
rc =- ENOMEM;
printk(KERN_ERR "hmac_sha256: failed to allocate request for hmac(sha512)(%s).\n", get_error(rc));
}
if(key_size){
if((rc = crypto_ahash_setkey(tfm, key, key_size))){
printk(KERN_ERR "hmac_sha256: crypto_ahash_setkey failed.(%s)\n", get_error(rc));
goto out;
}
}
sg_init_table(&pending_sgl, 1);
memset(req->__ctx, TESTMGR_POISON_BYTE, crypto_ahash_reqsize(tfm));
ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, crypto_req_done, &wait);
ahash_request_set_crypt(req, NULL, okm, 0);
rc = do_ahash_op(crypto_ahash_init, req, &wait);
rc = check_nonfinal_ahash_op("crypto_ahash_init", rc);
if (rc)
goto out;
sg_set_buf(&pending_sgl, ikm, ikm_len);
ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, crypto_req_done, &wait);
ahash_request_set_crypt(req, &pending_sgl, okm, okm_len);
rc = do_ahash_op(crypto_ahash_update, req, &wait);
rc = check_nonfinal_ahash_op("crypto_ahash_update", rc);
if(rc)
goto out;
rc = do_ahash_op(crypto_ahash_final, req, &wait);
rc = check_nonfinal_ahash_op("crypto_ahash_final", rc);
if (rc)
goto out;
dump_memory(okm, "hmac_sha256", okm_len);
out:
ahash_request_free(req);
crypto_free_ahash(tfm);
err_tfm:
if(key_is_null)
kfree(key);
return rc;
}
Break A leg!
int hkdf_extract(unsigned char *salt, size_t salt_len, unsigned char *ikm, size_t ikm_len, unsigned char *okm, size_t okm_len){
return hmac_sha256(salt, salt_len, ikm, ikm_len, okm, okm_len);
}

record using /pulse/simple.h

i am trying to record my voice from the microphone on my laptop using the simple.h pulseaudio header file into an array, but i cant seem to figure it out. Every time i record and i replay my recording , it is a high pitched beep i followed examples, etc but i can't seem to get this down can someone please help me .
I am basically hacking the example "parec-simple.c" given in the doxygen page. I've tried routing the output of buf to stdout, then using libre-office calc to plot a graph to see if the output looks anything like sound but it does not.
here is the code i used
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <pulse/simple.h>
#include <pulse/error.h>
#define BUFSIZE 1024
FILE *output;
/* A simple routine calling UNIX write() in a loop */
void loop_write(uint8_t *data) {
register int size = 1023;
while (size > 0)
{
fprintf(output,"%"SCNu8"\n",data[size] ) ;
size --;
}
}
int main(int argc, char*argv[]) {
output = fopen("/home/donnell/output", "w");
/* The sample type to use */
static const pa_sample_spec ss = {
.format = PA_SAMPLE_S16LE,
.rate = 41000,
.channels = 2
};
pa_simple *s = NULL;
int ret = 1;
int error;
/* Create the recording stream */
if (!(s = pa_simple_new(NULL, argv[0], PA_STREAM_RECORD, NULL, "record", &ss, NULL, NULL, &error))) {
fprintf(stderr, __FILE__": pa_simple_new() failed: %s\n", pa_strerror(error));
goto finish;
}
for (;;) {
uint8_t buf[BUFSIZE];
/* Record some data ... */
if (pa_simple_read(s, buf, sizeof(buf), &error) < 0) {
fprintf(stderr, __FILE__": pa_simple_read() failed: %s\n", pa_strerror(error));
goto finish;
}
/* and write it to fle*/
loop_write(buf);
}
ret = 0;
finish:
if (s)
pa_simple_free(s);
return ret;
}

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