keep-alive curl C htttps POST - c

With this code I am sending strings to a webserver using libcurl and write the data to a MySQL (is done at the webserver).
My Problem is that for every call of this function the program starts a new key exchange with the webserver. I would like to have a persistant connection to the Server.
I searched here and web already and didnt find any satisfying solutions.
Multi-handler and forced keep alive still open a new connection.
Following is my Code to establish an SSL Connection:
CURL *curl;
CURLcode res;
res = curl_global_init(CURL_GLOBAL_DEFAULT); // Check for errors
if(res != CURLE_OK) {
fprintf(stderr, "curl_global_init() failed: %s\n",
curl_easy_strerror(res));
return 1;
}
// curl handler
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, STRING);
curl_easy_setopt(curl, CURLOPT_URL, "https://IP/something/something.php");
curl_easy_setopt(curl, CURLOPT_TCP_KEEPALIVE, 1L);
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); //verbose output activated
struct curl_slist *headers=NULL;
headers = curl_slist_append(headers, "Content-Type: application/json"); // type JSON
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
// Perform the request, res will get the return code
res = curl_easy_perform(curl);
// Check for errors
if(res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
// cleanup
curl_slist_free_all(headers);
curl_easy_cleanup(curl);
}
curl_global_cleanup();

is Answered by Daniel Stenberg here, which is a similar/the same question.
Re-use the same curl handle in subsequent requests! Don't call curl_easy_cleanup(curl) and curl_easy_init() again between them.
So the Solution is to call curl_easy_cleanup(curl) and curl_easy_init() only once.

Related

Use curl with a webpage with no security protocol

I have a webpage: 10.1.1.165 that I am trying to get the data off of. I have built this program in linux and it works fine, however, when developing for windows systems I am running into an issue.
if (filename.substr(filename.length() - 4, 4) == "html" || filename.substr(filename.length() - 3, 3) == "htm")
{
CURL *curl;
CURLcode res;
curl_global_init(CURL_GLOBAL_DEFAULT);
curl = curl_easy_init();
string s;
if (curl)
{
curl_easy_setopt(curl, CURLOPT_URL, filename.c_str());
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
if (gLogger->isDebug()) curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
curl_easy_setopt(curl, CURLOPT_TIMEOUT, timeout/1000);
//curl_easy_setopt (curl, CURLOPT_VERBOSE, 1L); //remove this to disable verbose output
// Perform the request, res will get the return code
res = curl_easy_perform(curl);
// Check for errors
if (res != CURLE_OK)
{
while (res == CURLE_OPERATION_TIMEDOUT)
{
res = curl_easy_perform(curl);
}
if (res != CURLE_OK)
{
gLogger->error("curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
curl_easy_cleanup(curl);
return -1;
}
}
curl_easy_cleanup(curl);
On my linux system, this works perfectly. On my Windows system I get: curl_easy_perform() failed: Unsupported protocol. If I go to my webpage 10.1.1.165 I see that it is being hosted with NO security. I have no way of changing how that webpage is being hosted.
Per this resource: https://curl.haxx.se/libcurl/c/CURLOPT_PROTOCOLS.html
By default libcurl will accept all protocols
Does anyone know why curl doesn't like me grabbing this webpage on windows? And if so, what settings might I have to adjust?
I have solved my issue by switching to curl-7.55.1. Previously I was using curl-7.68.0. I'm not sure if the functionality was removed or if using it is more involved.

C - Libcurl - How to search for Mails with special chars (ä,ö,ü)

i use libcurl to search for mails in my mailbox.
But i cannot search mails with mails that inlcudes special chars (ä,ö,ü) in the subject.
int main(void)
{
CURL *curl;
CURLcode res = CURLE_OK;
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_USERNAME, "myuser");
curl_easy_setopt(curl, CURLOPT_PASSWORD, "mypassword");
curl_easy_setopt(curl, CURLOPT_URL, "imaps://imap.gmail.com:993/INBOX");
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "SEARCH SUBJECT Spülmaschine");
res = curl_easy_perform(curl);
if(res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
curl_easy_cleanup(curl);
}
return (int)res;
}
The mail cannot be found.
I searching a while but i cannot find some tipps.
Have someone any ideas ?
EDIT:// No one of the following trys will work:
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "SEARCH CHARSET UTF-8 SUBJECT \x53\x70\xc3\xbc\x6c\x6d\x61\x73\x63\x68\x69\x6e\x65");
//try it with UTF-7
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "SEARCH SUBJECT Sp+APw-lmaschine");
sprintf(strSearchString, "SEARCH CHARSET UTF-8 SUBJECT {%i}\r\n\x53\x70\xc3\xbc\x6c\x6d\x61\x73\x63\x68\x69\x6e\x65", strlen("\x53\x70\xc3\xbc\x6c\x6d\x61\x73\x63\x68\x69\x6e\x65"));
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, strSearchString);
After a long time i found a solution:
int main(void) {
CURL *curl;
CURLcode res = CURLE_OK;
curl = curl_easy_init();
if (curl) {
curl_easy_setopt(curl, CURLOPT_USERNAME, "myuser");
curl_easy_setopt(curl, CURLOPT_PASSWORD, "mypass");
curl_easy_setopt(curl, CURLOPT_URL, "imaps://imap.gmail.com:993");
// see RFC6855 IMAP Support for UTF-8
// imap.gmail.com states UTF8=ACCEPT in CAPABILITY response,
// so enable it to use UTF-8 in quoted strings.
// Must come after AUTHENTICATE and before SELECT.
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "ENABLE UTF8=ACCEPT");
res = curl_easy_perform(curl);
if (res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
// SELECT INBOX broken out from URL
if (res == CURLE_OK) {
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "SELECT INBOX");
res = curl_easy_perform(curl);
if (res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
}
if (res == CURLE_OK) {
// U+00FC LATIN SMALL LETTER U WITH DIAERESIS is \xC3\xBC in UTF-8
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "SEARCH
SUBJECT \"Sp\xC3\xBClmaschine\"");
res = curl_easy_perform(curl);
if (res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
}
curl_easy_cleanup(curl);
}
return (int) res;
}
While technically against protocol for including 8-bit characters, try SEARCH CHARSET UTF-8 SUBJECT "spülmaschine", and make sure you really are sending UTF-8 and not some other encoding. This will work on many servers. I do not know if you can make libcurl do it the proper way with an IMAP literal.
Note: some server software just doesn't support search that well. Remember, you can always use a tool like socat or python's imaplib, which give you pretty low level access to the protocol for experimenting.

Copy a file to HTTP Server through C program

< HTTP/1.1 405 Method Not Allowed
even i am using POSt in curl API, it is saying that PUT method is not allowd.
< Date: Fri, 20 May 2016 11:03:06 GMT
* Server Apache/2.2.15 (CentOS) is not blacklisted
< Server: Apache/2.2.15 (CentOS)
< Allow: GET,HEAD,POST,OPTIONS,TRACE
< Content-Length: 318
< Connection: close
< Content-Type: text/html; charset=iso-8859-1
getting above error,while i am trying to use HTTP POST. below is the code that i am trying
curl = curl_easy_init();
if(curl) {
/* upload to this place */
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
/* tell it to "upload" to the URL */
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
curl_easy_setopt(curl, CURLOPT_POST, 1L);
// curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
/* set where to read from */
curl_easy_setopt(curl, CURLOPT_READDATA, fd);
/* and give the size of the upload (optional) */
curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE,
(curl_off_t)file_info.st_size);
/* enable verbose for easier tracing */
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
res = curl_easy_perform(curl);
/* Check for errors */
if(res != CURLE_OK) {
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
}
}
Leave just CURLOPT_POST and remove CURLOPT_UPLOAD. See this question.
It seems that libcURL does something internally when you set CURLOPT_UPLOAD that "locks" the PUT method to the handle, as noticed in this other question, making the following curl_easy_setopt with CURLOPT_POST ineffective.

Reusing curl easy handles in C

In a C project I want to reuse curl easy handles. The flow of program is like:
Client --> C Application --> Call URL1, do something, Call URL2, do something, Call URL3...
In short, for each client request, the same set of URLs are called.
I initially create the curl easy handle when the program starts. The main program creates a configurable number of child, so each child gets its own easy handle.
static int child_init(int rank) {
LM_NOTICE("init_child [%d] pid [%d]\n", rank, getpid());
pid = my_pid();
curl_global_init(CURL_GLOBAL_ALL);
// initialize curl handle
curl = curl_easy_init();
if (!curl) {
LM_ERR("Child %d: Curl initialization failed.\n", rank);
return -1;
}
//create some connections before actual requests come.
curl_head(URL);
return 0;
}
I created a C file where the functions are created to handle GET/POST/PUT etc requests:
int curl_head(const char* url) {
if (!url) {
LM_ERR("URL not provided. Returning with error.\n");
return -1;
}
CURLcode res;
int http_code = 0;
struct curl_slist *headers = NULL;
headers = curl_slist_append(headers, "charsets: utf-8");
/* set URL */
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "HEAD");
curl_easy_setopt(curl, CURLOPT_NOBODY, 1L);
res = curl_easy_perform(curl);
if (res != CURLE_OK) {
LM_ERR("curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
}
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
LM_DBG("HTTP return CODE %d\n", http_code);
curl_slist_free_all(headers);
curl_easy_reset(curl);
return http_code;
}
int curl_post(const char* url, char *postdata) {
if (!url) {
LM_ERR("URL not provided. Returning with error.\n");
return -1;
}
CURLcode res;
int http_code = 0;
struct curl_slist *headers = NULL;
headers = curl_slist_append(headers, "Accept: application/json");
headers = curl_slist_append(headers, "Content-Type: application/json");
headers = curl_slist_append(headers, "charsets: utf-8");
/* set URL */
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, postdata);
curl_easy_setopt(curl, CURLOPT_USERAGENT, "libcrp/0.1");
res = curl_easy_perform(curl);
if (res != CURLE_OK) {
LM_ERR("curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
}
curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
curl_slist_free_all(headers);
curl_easy_reset(curl);
return http_code;
}
When somewhere in the program I want to call the WS I call the desired function as curl_post(url).
Am I doing this correctly or are there any flaws in this implementation?

curl wsdl soap error - mismatched Actions between sender and receiver

I am trying to post the curl based soap request to url using c API's. My libcurl version is curl 7.30.0 (i686-pc-linux-gnu) libcurl/7.30.0 OpenSSL/1.0.0 zlib/1.2.5.I am receiving the below error.Also below code i am using to post the request.i am using correct soap action aswell "GetAuthToken", Why this error is happening while posting the request.Thanks in advance.
Error:
The message with Action '' cannot be processed at the receiver, due to a ContractFilter mismatch at the EndpointDispatcher. This may be because of either a contract mismatch (mismatched Actions between sender and receiver) or a binding/security mismatch between the sender and the receiver. Check that sender and receiver have the same contract and the same binding (including security requirements, e.g. Message, Transport, None)
Request:
123456789
url:
http://x.xx.xx.xxx:20003/HIMS/SecurityService/?wsdl
Sample code:
int main()
{
CURL *curl;
CURLcode res;
struct curl_slist *headers = NULL;
FILE *out_fd = (FILE *) 0;
char errorbuf[300]="",filename[32]="Response.txt";
char errmsg[256];
int Timeout=120;
int buffer_size = 0;
char urlbuff[100]="";
char buff[128] = "http://x.xx.xx.xxx:20003/HIMS/SecurityService/?wsdl";
memset(urlbuff,0,sizeof(urlbuff));
curl = curl_easy_init();
buffer_size = strlen(buffer);
if(curl)
{
out_fd = fopen (filename, "w");
curl_easy_setopt(curl, CURLOPT_FILE, out_fd);
headers = curl_slist_append(headers, "Content-type:text/xml;charset=utf-8; SOAPAction=GetAuthToken");
sprintf(urlbuff,"%s",buff);
curl_easy_setopt(curl, CURLOPT_URL, urlbuff);
Timeout=2000;
curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0);
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, buffer_size);
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, buffer);
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
curl_easy_setopt(curl, CURLOPT_TIMEOUT, Timeout);
curl_easy_setopt(curl, CURLOPT_ERRORBUFFER,errmsg);
res = curl_easy_perform(curl);
curl_slist_free_all(headers);
curl_easy_cleanup(curl);
fclose(out_fd);
if(CURLE_OK != res)
{
printf("\nerrorbuf:%s:%d\n",errorbuf,res);
return -1;
}
return 0;
}
}
Assuming you have created a valid soap envelope for this request. In your code, you missed to define a POST request with your curl.
curl_easy_setopt(curl, CURLOPT_POST, 1L);

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