cregit-Linux how code gets into the kernel

Release 4.10 tools/hv/hv_kvp_daemon.c

Directory: tools/hv
/*
 * An implementation of key value pair (KVP) functionality for Linux.
 *
 *
 * Copyright (C) 2010, Novell, Inc.
 * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */


#include <sys/poll.h>
#include <sys/utsname.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <arpa/inet.h>
#include <linux/hyperv.h>
#include <ifaddrs.h>
#include <netdb.h>
#include <syslog.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <dirent.h>
#include <net/if.h>
#include <getopt.h>

/*
 * KVP protocol: The user mode component first registers with the
 * the kernel component. Subsequently, the kernel component requests, data
 * for the specified keys. In response to this message the user mode component
 * fills in the value corresponding to the specified key. We overload the
 * sequence field in the cn_msg header to define our KVP message types.
 *
 * We use this infrastructure for also supporting queries from user mode
 * application for state that may be maintained in the KVP kernel component.
 *
 */



enum key_index {
	
FullyQualifiedDomainName = 0,
	
IntegrationServicesVersion, /*This key is serviced in the kernel*/
	
NetworkAddressIPv4,
	
NetworkAddressIPv6,
	
OSBuildNumber,
	
OSName,
	
OSMajorVersion,
	
OSMinorVersion,
	
OSVersion,
	
ProcessorArchitecture
};


enum {
	
IPADDR = 0,
	
NETMASK,
	
GATEWAY,
	
DNS
};


static int in_hand_shake = 1;


static char *os_name = "";

static char *os_major = "";

static char *os_minor = "";

static char *processor_arch;

static char *os_build;

static char *os_version;

static char *lic_version = "Unknown version";

static char full_domain_name[HV_KVP_EXCHANGE_MAX_VALUE_SIZE];

static struct utsname uts_buf;

/*
 * The location of the interface configuration file.
 */


#define KVP_CONFIG_LOC	"/var/lib/hyperv"

#ifndef KVP_SCRIPTS_PATH

#define KVP_SCRIPTS_PATH "/usr/libexec/hypervkvpd/"
#endif


#define MAX_FILE_NAME 100

#define ENTRIES_PER_BLOCK 50


struct kvp_record {
	
char key[HV_KVP_EXCHANGE_MAX_KEY_SIZE];
	
char value[HV_KVP_EXCHANGE_MAX_VALUE_SIZE];
};


struct kvp_file_state {
	
int fd;
	
int num_blocks;
	
struct kvp_record *records;
	
int num_records;
	
char fname[MAX_FILE_NAME];
};


static struct kvp_file_state kvp_file_info[KVP_POOL_COUNT];




static void kvp_acquire_lock(int pool)
{
	struct flock fl = {F_WRLCK, SEEK_SET, 0, 0, 0};
	fl.l_pid = getpid();

	if (fcntl(kvp_file_info[pool].fd, F_SETLKW, &fl) == -1) {
		syslog(LOG_ERR, "Failed to acquire the lock pool: %d; error: %d %s", pool,
				errno, strerror(errno));
		exit(EXIT_FAILURE);
	}
}


Contributors
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tomas hozzatomas hozza810.67%133.33%


ben hutchingsben hutchings11.33%133.33%


Total75100.00%3100.00%






static void kvp_release_lock(int pool)
{
	struct flock fl = {F_UNLCK, SEEK_SET, 0, 0, 0};
	fl.l_pid = getpid();

	if (fcntl(kvp_file_info[pool].fd, F_SETLK, &fl) == -1) {
		syslog(LOG_ERR, "Failed to release the lock pool: %d; error: %d %s", pool,
				errno, strerror(errno));
		exit(EXIT_FAILURE);
	}
}


Contributors
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ky srinivasanky srinivasan6688.00%133.33%


tomas hozzatomas hozza810.67%133.33%


ben hutchingsben hutchings11.33%133.33%


Total75100.00%3100.00%






static void kvp_update_file(int pool)
{
	FILE *filep;

	/*
         * We are going to write our in-memory registry out to
         * disk; acquire the lock first.
         */
	kvp_acquire_lock(pool);

	filep = fopen(kvp_file_info[pool].fname, "we");
	if (!filep) {
		syslog(LOG_ERR, "Failed to open file, pool: %d; error: %d %s", pool,
				errno, strerror(errno));
		kvp_release_lock(pool);
		exit(EXIT_FAILURE);
	}

	fwrite(kvp_file_info[pool].records, sizeof(struct kvp_record),
				kvp_file_info[pool].num_records, filep);

	if (ferror(filep) || fclose(filep)) {
		kvp_release_lock(pool);
		syslog(LOG_ERR, "Failed to write file, pool: %d", pool);
		exit(EXIT_FAILURE);
	}

	kvp_release_lock(pool);
}


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ky srinivasanky srinivasan8565.89%116.67%


ben hutchingsben hutchings3023.26%350.00%


tomas hozzatomas hozza1410.85%233.33%


Total129100.00%6100.00%






static void kvp_update_mem_state(int pool)
{
	FILE *filep;
	size_t records_read = 0;
	struct kvp_record *record = kvp_file_info[pool].records;
	struct kvp_record *readp;
	int num_blocks = kvp_file_info[pool].num_blocks;
	int alloc_unit = sizeof(struct kvp_record) * ENTRIES_PER_BLOCK;

	kvp_acquire_lock(pool);

	filep = fopen(kvp_file_info[pool].fname, "re");
	if (!filep) {
		syslog(LOG_ERR, "Failed to open file, pool: %d; error: %d %s", pool,
				errno, strerror(errno));
		kvp_release_lock(pool);
		exit(EXIT_FAILURE);
	}
	for (;;) {
		readp = &record[records_read];
		records_read += fread(readp, sizeof(struct kvp_record),
					ENTRIES_PER_BLOCK * num_blocks,
					filep);

		if (ferror(filep)) {
			syslog(LOG_ERR, "Failed to read file, pool: %d", pool);
			exit(EXIT_FAILURE);
		}

		if (!feof(filep)) {
			/*
                         * We have more data to read.
                         */
			num_blocks++;
			record = realloc(record, alloc_unit * num_blocks);

			if (record == NULL) {
				syslog(LOG_ERR, "malloc failed");
				exit(EXIT_FAILURE);
			}
			continue;
		}
		break;
	}

	kvp_file_info[pool].num_blocks = num_blocks;
	kvp_file_info[pool].records = record;
	kvp_file_info[pool].num_records = records_read;

	fclose(filep);
	kvp_release_lock(pool);
}

Contributors
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ky srinivasanky srinivasan20080.32%116.67%


ben hutchingsben hutchings3514.06%350.00%


tomas hozzatomas hozza145.62%233.33%


Total249100.00%6100.00%






static int kvp_file_init(void)
{
	int  fd;
	FILE *filep;
	size_t records_read;
	char *fname;
	struct kvp_record *record;
	struct kvp_record *readp;
	int num_blocks;
	int i;
	int alloc_unit = sizeof(struct kvp_record) * ENTRIES_PER_BLOCK;

	if (access(KVP_CONFIG_LOC, F_OK)) {
		if (mkdir(KVP_CONFIG_LOC, 0755 /* rwxr-xr-x */)) {
			syslog(LOG_ERR, "Failed to create '%s'; error: %d %s", KVP_CONFIG_LOC,
					errno, strerror(errno));
			exit(EXIT_FAILURE);
		}
	}

	for (i = 0; i < KVP_POOL_COUNT; i++) {
		fname = kvp_file_info[i].fname;
		records_read = 0;
		num_blocks = 1;
		sprintf(fname, "%s/.kvp_pool_%d", KVP_CONFIG_LOC, i);
		fd = open(fname, O_RDWR | O_CREAT | O_CLOEXEC, 0644 /* rw-r--r-- */);

		if (fd == -1)
			return 1;


		filep = fopen(fname, "re");
		if (!filep) {
			close(fd);
			return 1;
		}

		record = malloc(alloc_unit * num_blocks);
		if (record == NULL) {
			fclose(filep);
			close(fd);
			return 1;
		}
		for (;;) {
			readp = &record[records_read];
			records_read += fread(readp, sizeof(struct kvp_record),
					ENTRIES_PER_BLOCK,
					filep);

			if (ferror(filep)) {
				syslog(LOG_ERR, "Failed to read file, pool: %d",
				       i);
				exit(EXIT_FAILURE);
			}

			if (!feof(filep)) {
				/*
                                 * We have more data to read.
                                 */
				num_blocks++;
				record = realloc(record, alloc_unit *
						num_blocks);
				if (record == NULL) {
					fclose(filep);
					close(fd);
					return 1;
				}
				continue;
			}
			break;
		}
		kvp_file_info[i].fd = fd;
		kvp_file_info[i].num_blocks = num_blocks;
		kvp_file_info[i].records = record;
		kvp_file_info[i].num_records = records_read;
		fclose(filep);

	}

	return 0;
}


Contributors
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ky srinivasanky srinivasan29581.27%222.22%


tomas hozzatomas hozza359.64%444.44%


ben hutchingsben hutchings339.09%333.33%


Total363100.00%9100.00%






static int kvp_key_delete(int pool, const __u8 *key, int key_size)
{
	int i;
	int j, k;
	int num_records;
	struct kvp_record *record;

	/*
         * First update the in-memory state.
         */
	kvp_update_mem_state(pool);

	num_records = kvp_file_info[pool].num_records;
	record = kvp_file_info[pool].records;

	for (i = 0; i < num_records; i++) {
		if (memcmp(key, record[i].key, key_size))
			continue;
		/*
                 * Found a match; just move the remaining
                 * entries up.
                 */
		if (i == num_records) {
			kvp_file_info[pool].num_records--;
			kvp_update_file(pool);
			return 0;
		}

		j = i;
		k = j + 1;
		for (; k < num_records; k++) {
			strcpy(record[j].key, record[k].key);
			strcpy(record[j].value, record[k].value);
			j++;
		}

		kvp_file_info[pool].num_records--;
		kvp_update_file(pool);
		return 0;
	}
	return 1;
}


Contributors
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ky srinivasanky srinivasan19098.96%250.00%


vitaly kuznetsovvitaly kuznetsov10.52%125.00%


tomas hozzatomas hozza10.52%125.00%


Total192100.00%4100.00%






static int kvp_key_add_or_modify(int pool, const __u8 *key, int key_size,
				 const __u8 *value, int value_size)
{
	int i;
	int num_records;
	struct kvp_record *record;
	int num_blocks;

	if ((key_size > HV_KVP_EXCHANGE_MAX_KEY_SIZE) ||
		(value_size > HV_KVP_EXCHANGE_MAX_VALUE_SIZE))
		return 1;

	/*
         * First update the in-memory state.
         */
	kvp_update_mem_state(pool);

	num_records = kvp_file_info[pool].num_records;
	record = kvp_file_info[pool].records;
	num_blocks = kvp_file_info[pool].num_blocks;

	for (i = 0; i < num_records; i++) {
		if (memcmp(key, record[i].key, key_size))
			continue;
		/*
                 * Found a match; just update the value -
                 * this is the modify case.
                 */
		memcpy(record[i].value, value, value_size);
		kvp_update_file(pool);
		return 0;
	}

	/*
         * Need to add a new entry;
         */
	if (num_records == (ENTRIES_PER_BLOCK * num_blocks)) {
		/* Need to allocate a larger array for reg entries. */
		record = realloc(record, sizeof(struct kvp_record) *
			 ENTRIES_PER_BLOCK * (num_blocks + 1));

		if (record == NULL)
			return 1;
		kvp_file_info[pool].num_blocks++;

	}
	memcpy(record[i].value, value, value_size);
	memcpy(record[i].key, key, key_size);
	kvp_file_info[pool].records = record;
	kvp_file_info[pool].num_records++;
	kvp_update_file(pool);
	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
ky srinivasanky srinivasan24598.39%250.00%


tomas hozzatomas hozza20.80%125.00%


vitaly kuznetsovvitaly kuznetsov20.80%125.00%


Total249100.00%4100.00%






static int kvp_get_value(int pool, const __u8 *key, int key_size, __u8 *value,
			int value_size)
{
	int i;
	int num_records;
	struct kvp_record *record;

	if ((key_size > HV_KVP_EXCHANGE_MAX_KEY_SIZE) ||
		(value_size > HV_KVP_EXCHANGE_MAX_VALUE_SIZE))
		return 1;

	/*
         * First update the in-memory state.
         */
	kvp_update_mem_state(pool);

	num_records = kvp_file_info[pool].num_records;
	record = kvp_file_info[pool].records;

	for (i = 0; i < num_records; i++) {
		if (memcmp(key, record[i].key, key_size))
			continue;
		/*
                 * Found a match; just copy the value out.
                 */
		memcpy(value, record[i].value, value_size);
		return 0;
	}

	return 1;
}


Contributors
PersonTokensPropCommitsCommitProp
ky srinivasanky srinivasan12496.12%350.00%


olaf heringolaf hering21.55%116.67%


vitaly kuznetsovvitaly kuznetsov21.55%116.67%


tomas hozzatomas hozza10.78%116.67%


Total129100.00%6100.00%






static int kvp_pool_enumerate(int pool, int index, __u8 *key, int key_size,
				__u8 *value, int value_size)
{
	struct kvp_record *record;

	/*
         * First update our in-memory database.
         */
	kvp_update_mem_state(pool);
	record = kvp_file_info[pool].records;

	if (index >= kvp_file_info[pool].num_records) {
		return 1;
	}

	memcpy(key, record[index].key, key_size);
	memcpy(value, record[index].value, value_size);
	return 0;
}



Contributors
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ky srinivasanky srinivasan9197.85%266.67%


vitaly kuznetsovvitaly kuznetsov22.15%133.33%


Total93100.00%3100.00%






void kvp_get_os_info(void)
{
	FILE	*file;
	char	*p, buf[512];

	uname(&uts_buf);
	os_version = uts_buf.release;
	os_build = strdup(uts_buf.release);

	os_name = uts_buf.sysname;
	processor_arch = uts_buf.machine;

	/*
         * The current windows host (win7) expects the build
         * string to be of the form: x.y.z
         * Strip additional information we may have.
         */
	p = strchr(os_version, '-');
	if (p)
		*p = '\0';

	/*
         * Parse the /etc/os-release file if present:
         * http://www.freedesktop.org/software/systemd/man/os-release.html
         */
	file = fopen("/etc/os-release", "r");
	if (file != NULL) {
		while (fgets(buf, sizeof(buf), file)) {
			char *value, *q;

			/* Ignore comments */
			if (buf[0] == '#')
				continue;

			/* Split into name=value */
			p = strchr(buf, '=');
			if (!p)
				continue;
			*p++ = 0;

			/* Remove quotes and newline; un-escape */
			value = p;
			q = p;
			while (*p) {
				if (*p == '\\') {
					++p;
					if (!*p)
						break;
					*q++ = *p++;
				} else if (*p == '\'' || *p == '"' ||
					   *p == '\n') {
					++p;
				} else {
					*q++ = *p++;
				}
			}
			*q = 0;

			if (!strcmp(buf, "NAME")) {
				p = strdup(value);
				if (!p)
					break;
				os_name = p;
			} else if (!strcmp(buf, "VERSION_ID")) {
				p = strdup(value);
				if (!p)
					break;
				os_major = p;
			}
		}
		fclose(file);
		return;
	}

	/* Fallback for older RH/SUSE releases */
	file = fopen("/etc/SuSE-release", "r");
	if (file != NULL)
		goto kvp_osinfo_found;
	file  = fopen("/etc/redhat-release", "r");
	if (file != NULL)
		goto kvp_osinfo_found;

	/*
         * We don't have information about the os.
         */
	return;

kvp_osinfo_found:
	/* up to three lines */
	p = fgets(buf, sizeof(buf), file);
	if (p) {
		p = strchr(buf, '\n');
		if (p)
			*p = '\0';
		p = strdup(buf);
		if (!p)
			goto done;
		os_name = p;

		/* second line */
		p = fgets(buf, sizeof(buf), file);
		if (p) {
			p = strchr(buf, '\n');
			if (p)
				*p = '\0';
			p = strdup(buf);
			if (!p)
				goto done;
			os_major = p;

			/* third line */
			p = fgets(buf, sizeof(buf), file);
			if (p)  {
				p = strchr(buf, '\n');
				if (p)
					*p = '\0';
				p = strdup(buf);
				if (p)
					os_minor = p;
			}
		}
	}

done:
	fclose(file);
	return;
}




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ky srinivasanky srinivasan15329.88%360.00%


olaf heringolaf hering13125.59%120.00%


Total512100.00%5100.00%



/*
 * Retrieve an interface name corresponding to the specified guid.
 * If there is a match, the function returns a pointer
 * to the interface name and if not, a NULL is returned.
 * If a match is found, the caller is responsible for
 * freeing the memory.
 */




static char *kvp_get_if_name(char *guid)
{
	DIR *dir;
	struct dirent *entry;
	FILE    *file;
	char    *p, *q, *x;
	char    *if_name = NULL;
	char    buf[256];
	char *kvp_net_dir = "/sys/class/net/";
	char dev_id[256];

	dir = opendir(kvp_net_dir);
	if (dir == NULL)
		return NULL;

	snprintf(dev_id, sizeof(dev_id), "%s", kvp_net_dir);
	q = dev_id + strlen(kvp_net_dir);

	while ((entry = readdir(dir)) != NULL) {
		/*
                 * Set the state for the next pass.
                 */
		*q = '\0';
		strcat(dev_id, entry->d_name);
		strcat(dev_id, "/device/device_id");

		file = fopen(dev_id, "r");
		if (file == NULL)
			continue;

		p = fgets(buf, sizeof(buf), file);
		if (p) {
			x = strchr(p, '\n');
			if (x)
				*x = '\0';

			if (!strcmp(p, guid)) {
				/*
                                 * Found the guid match; return the interface
                                 * name. The caller will free the memory.
                                 */
				if_name = strdup(entry->d_name);
				fclose(file);
				break;
			}
		}
		fclose(file);
	}

	closedir(dir);
	return if_name;
}


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Total229100.00%2100.00%



/*
 * Retrieve the MAC address given the interface name.
 */




static char *kvp_if_name_to_mac(char *if_name)
{
	FILE    *file;
	char    *p, *x;
	char    buf[256];
	char addr_file[256];
	unsigned int i;
	char *mac_addr = NULL;

	snprintf(addr_file, sizeof(addr_file), "%s%s%s", "/sys/class/net/",
		if_name, "/address");

	file = fopen(addr_file, "r");
	if (file == NULL)
		return NULL;

	p = fgets(buf, sizeof(buf), file);
	if (p) {
		x = strchr(p, '\n');
		if (x)
			*x = '\0';
		for (i = 0; i < strlen(p); i++)
			p[i] = toupper(p[i]);
		mac_addr = strdup(p);
	}

	fclose(file);
	return mac_addr;
}



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ky srinivasanky srinivasan16199.38%480.00%


vitaly kuznetsovvitaly kuznetsov10.62%120.00%


Total162100.00%5100.00%



/*
 * Retrieve the interface name given tha MAC address.
 */




static char *kvp_mac_to_if_name(char *mac)
{
	DIR *dir;
	struct dirent *entry;
	FILE    *file;
	char    *p, *q, *x;
	char    *if_name = NULL;
	char    buf[256];
	char *kvp_net_dir = "/sys/class/net/";
	char dev_id[256];
	unsigned int i;

	dir = opendir(kvp_net_dir);
	if (dir == NULL)
		return NULL;

	snprintf(dev_id, sizeof(dev_id), "%s", kvp_net_dir);
	q = dev_id + strlen(kvp_net_dir);

	while ((entry = readdir(dir)) != NULL) {
		/*
                 * Set the state for the next pass.
                 */
		*q = '\0';

		strcat(dev_id, entry->d_name);
		strcat(dev_id, "/address");

		file = fopen(dev_id, "r");
		if (file == NULL)
			continue;

		p =