[libvirt] [PATCH v4 4/5] Network: Add additional hosts internal infrastructure

Signed-off-by: Michal Novotny <minovotn(a)redhat.com&gt; --- docs/formatnetwork.html.in | 9 +- src/libvirt_private.syms | 1 + src/network/bridge_driver.c | 3 + src/util/dnsmasq.c | 285 ++++++++++++++++++++++++++++++++++++++++--- src/util/dnsmasq.h | 22 +++- 5 files changed, 298 insertions(+), 22 deletions(-) diff --git a/docs/formatnetwork.html.in b/docs/formatnetwork.html.in index 008897d..95d9c1a 100644 --- a/docs/formatnetwork.html.in +++ b/docs/formatnetwork.html.in @@ -183,8 +183,6 @@ or commas. value is a single string that can contain multiple values which are comma-separated which is allowed for the TXT records and it is represented a single value. <span class="since">Since 0.9.1</span> - </dd> - </dd><dt><code>dhcp</code></dt><dd>Also within the <code>ip</code> element there is an optional <code>dhcp</code> element. The presence of this element enables DHCP services on the virtual network. It will further @@ -220,6 +218,13 @@ for all address ranges and statically assigned addresses.<span class="since">Since 0.7.1 (<code>server</code> since 0.7.3).</span> </dd> + <dt><code>host</code></dt> + <dd>The <code>host</code> element is the definition of DNS hosts to be passed + to the DNS service. The IP address is identified by the <code>ip</code> attribute + and the names for the IP addresses are identified in the <code>hostname</code> + subelements of the <code>host</code> element. + <span class="since">Since 0.9.1</span> + </dd> </dl> <h2><a name="examples">Example configuration</a></h2> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 737cd31..71ef9cc 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -194,6 +194,7 @@ virUnrefStream; # dnsmasq.h dnsmasqAddDhcpHost; +dnsmasqAddHost; dnsmasqContextFree; dnsmasqContextNew; dnsmasqDelete; diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index 4873dc3..8f68f1c 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -609,6 +609,9 @@ networkBuildDnsmasqArgv(virNetworkObjPtr network, if (dctx->hostsfile->nhosts) virCommandAddArgPair(cmd, "--dhcp-hostsfile", dctx->hostsfile->path); + if (dctx->addnhostsfile->nhosts) + virCommandAddArgPair(cmd, "--addn-hosts", + dctx->addnhostsfile->path); dnsmasqContextFree(dctx); } diff --git a/src/util/dnsmasq.c b/src/util/dnsmasq.c index 2ba9355..04a912a 100644 --- a/src/util/dnsmasq.c +++ b/src/util/dnsmasq.c @@ -48,6 +48,7 @@ #define VIR_FROM_THIS VIR_FROM_NETWORK #define DNSMASQ_HOSTSFILE_SUFFIX "hostsfile" +#define DNSMASQ_ADDNHOSTSFILE_SUFFIX "addnhosts" static void dhcphostFree(dnsmasqDhcpHost *host) @@ -56,6 +57,235 @@ dhcphostFree(dnsmasqDhcpHost *host) } static void +addnhostFree(dnsmasqAddnHost *host) +{ + int i; + + for (i = 0; i < host->nhostnames; i++) + VIR_FREE(host->hostnames[i]); + VIR_FREE(host->hostnames); + VIR_FREE(host->ip); +} + +static void +addnhostsFree(dnsmasqAddnHostsfile *addnhostsfile) +{ + unsigned int i; + + if (addnhostsfile->hosts) { + for (i = 0; i < addnhostsfile->nhosts; i++) + addnhostFree(&addnhostsfile->hosts[i]); + + VIR_FREE(addnhostsfile->hosts); + + addnhostsfile->nhosts = 0; + } + + VIR_FREE(addnhostsfile->path); + + VIR_FREE(addnhostsfile); +} + +static int +addnhostsAdd(dnsmasqAddnHostsfile *addnhostsfile, + virSocketAddr *ip, + const char *name) +{ + char *ipstr = NULL; + int idx = -1; + int i; + + if (!(ipstr = virSocketFormatAddr(ip))) + return -1; + + for (i = 0; i < addnhostsfile->nhosts; i++) { + if (STREQ((const char *)addnhostsfile->hosts[i].ip, (const char *)ipstr)) { + idx = i; + break; + } + } + + if (idx < 0) { + if (VIR_REALLOC_N(addnhostsfile->hosts, addnhostsfile->nhosts + 1) < 0) + goto alloc_error; + + idx = addnhostsfile->nhosts; + if (VIR_ALLOC(addnhostsfile->hosts[idx].hostnames) < 0) + goto alloc_error; + + if (virAsprintf(&addnhostsfile->hosts[idx].ip, "%s", ipstr) < 0) + goto alloc_error; + + addnhostsfile->hosts[idx].nhostnames = 0; + addnhostsfile->nhosts++; + } + + if (VIR_REALLOC_N(addnhostsfile->hosts[idx].hostnames, addnhostsfile->hosts[idx].nhostnames + 1) < 0) + goto alloc_error; + + if (virAsprintf(&addnhostsfile->hosts[idx].hostnames[addnhostsfile->hosts[idx].nhostnames], "%s", name) < 0) + goto alloc_error; + + VIR_FREE(ipstr); + + addnhostsfile->hosts[idx].nhostnames++; + + return 0; + + alloc_error: + virReportOOMError(); + VIR_FREE(ipstr); + return -1; +} + +static dnsmasqAddnHostsfile * +addnhostsNew(const char *name, + const char *config_dir) +{ + int err; + dnsmasqAddnHostsfile *addnhostsfile; + + if (VIR_ALLOC(addnhostsfile) < 0) { + virReportOOMError(); + return NULL; + } + + addnhostsfile->hosts = NULL; + addnhostsfile->nhosts = 0; + + if (virAsprintf(&addnhostsfile->path, "%s/%s.%s", config_dir, name, + DNSMASQ_ADDNHOSTSFILE_SUFFIX) < 0) { + virReportOOMError(); + goto error; + } + + if ((err = virFileMakePath(config_dir))) { + virReportSystemError(err, _("cannot create config directory '%s'"), + config_dir); + goto error; + } + + return addnhostsfile; + + error: + addnhostsFree(addnhostsfile); + return NULL; +} + +static int +addnhostsWrite(const char *path, + dnsmasqAddnHost *hosts, + unsigned int nhosts) +{ + char *tmp; + FILE *f; + bool istmp = true; + unsigned int i, ii; + int rc = 0; + + if (nhosts == 0) + return rc; + + if (virAsprintf(&tmp, "%s.new", path) < 0) + return -ENOMEM; + + if (!(f = fopen(tmp, "w"))) { + istmp = false; + if (!(f = fopen(path, "w"))) { + rc = errno; + goto cleanup; + } + } + + for (i = 0; i < nhosts; i++) { + if (fputs(hosts[i].ip, f) == EOF || fputc('\t', f) == EOF) { + rc = errno; + VIR_FORCE_FCLOSE(f); + + if (istmp) + unlink(tmp); + + goto cleanup; + } + + for (ii = 0; ii < hosts[i].nhostnames; ii++) { + if (fputs(hosts[i].hostnames[ii], f) == EOF || fputc('\t', f) == EOF) { + rc = errno; + VIR_FORCE_FCLOSE(f); + + if (istmp) + unlink(tmp); + + goto cleanup; + } + } + + if (fputc('\n', f) == EOF) { + rc = errno; + VIR_FORCE_FCLOSE(f); + + if (istmp) + unlink(tmp); + + goto cleanup; + } + } + + if (VIR_FCLOSE(f) == EOF) { + rc = errno; + goto cleanup; + } + + if (istmp) { + if (rename(tmp, path) < 0) { + rc = errno; + unlink(tmp); + goto cleanup; + } + + if (unlink(tmp) < 0) { + rc = errno; + goto cleanup; + } + } + + cleanup: + VIR_FREE(tmp); + + return rc; +} + +static int +addnhostsSave(dnsmasqAddnHostsfile *addnhostsfile) +{ + int err = addnhostsWrite(addnhostsfile->path, addnhostsfile->hosts, + addnhostsfile->nhosts); + + if (err < 0) { + virReportSystemError(err, _("cannot write config file '%s'"), + addnhostsfile->path); + return -1; + } + + return 0; +} + +static int +genericFileDelete(char *path) +{ + if (!virFileExists(path)) + return 0; + + if (unlink(path) < 0) { + virReportSystemError(errno, _("cannot remove config file '%s'"), + path); + return -1; + } + + return 0; +} + +static void hostsfileFree(dnsmasqHostsfile *hostsfile) { unsigned int i; @@ -220,21 +450,6 @@ hostsfileSave(dnsmasqHostsfile *hostsfile) return 0; } -static int -hostsfileDelete(dnsmasqHostsfile *hostsfile) -{ - if (!virFileExists(hostsfile->path)) - return 0; - - if (unlink(hostsfile->path) < 0) { - virReportSystemError(errno, _("cannot remove config file '%s'"), - hostsfile->path); - return -1; - } - - return 0; -} - /** * dnsmasqContextNew: * @@ -255,6 +470,8 @@ dnsmasqContextNew(const char *network_name, if (!(ctx->hostsfile = hostsfileNew(network_name, config_dir))) goto error; + if (!(ctx->addnhostsfile = addnhostsNew(network_name, config_dir))) + goto error; return ctx; @@ -277,6 +494,8 @@ dnsmasqContextFree(dnsmasqContext *ctx) if (ctx->hostsfile) hostsfileFree(ctx->hostsfile); + if (ctx->addnhostsfile) + addnhostsFree(ctx->addnhostsfile); VIR_FREE(ctx); } @@ -300,6 +519,24 @@ dnsmasqAddDhcpHost(dnsmasqContext *ctx, hostsfileAdd(ctx->hostsfile, mac, ip, name); } +/* + * dnsmasqAddHost: + * @ctx: pointer to the dnsmasq context for each network + * @ip: pointer to the socket address contains ip of the host + * @name: pointer to the string contains hostname of the host + * + * Add additional host entry. + */ + +void +dnsmasqAddHost(dnsmasqContext *ctx, + virSocketAddr *ip, + const char *name) +{ + if (ctx->addnhostsfile) + addnhostsAdd(ctx->addnhostsfile, ip, name); +} + /** * dnsmasqSave: * @ctx: pointer to the dnsmasq context for each network @@ -309,10 +546,16 @@ dnsmasqAddDhcpHost(dnsmasqContext *ctx, int dnsmasqSave(const dnsmasqContext *ctx) { + int ret = 0; + if (ctx->hostsfile) - return hostsfileSave(ctx->hostsfile); + ret = hostsfileSave(ctx->hostsfile); + if (ret == 0) { + if (ctx->addnhostsfile) + ret = addnhostsSave(ctx->addnhostsfile); + } - return 0; + return ret; } @@ -325,10 +568,14 @@ dnsmasqSave(const dnsmasqContext *ctx) int dnsmasqDelete(const dnsmasqContext *ctx) { + int ret = 0; + if (ctx->hostsfile) - return hostsfileDelete(ctx->hostsfile); + ret = genericFileDelete(ctx->hostsfile->path); + if (ctx->addnhostsfile) + ret = genericFileDelete(ctx->addnhostsfile->path); - return 0; + return ret; } /** diff --git a/src/util/dnsmasq.h b/src/util/dnsmasq.h index 02a961f..3f6320a 100644 --- a/src/util/dnsmasq.h +++ b/src/util/dnsmasq.h @@ -44,7 +44,24 @@ typedef struct typedef struct { - dnsmasqHostsfile *hostsfile; + unsigned int nhostnames; + char *ip; + char **hostnames; + +} dnsmasqAddnHost; + +typedef struct +{ + unsigned int nhosts; + dnsmasqAddnHost *hosts; + + char *path; /* Absolute path of dnsmasq's hostsfile. */ +} dnsmasqAddnHostsfile; + +typedef struct +{ + dnsmasqHostsfile *hostsfile; + dnsmasqAddnHostsfile *addnhostsfile; } dnsmasqContext; dnsmasqContext * dnsmasqContextNew(const char *network_name, @@ -54,6 +71,9 @@ void dnsmasqAddDhcpHost(dnsmasqContext *ctx, const char *mac, virSocketAddr *ip, const char *name); +void dnsmasqAddHost(dnsmasqContext *ctx, + virSocketAddr *ip, + const char *name); int dnsmasqSave(const dnsmasqContext *ctx); int dnsmasqDelete(const dnsmasqContext *ctx); int dnsmasqReload(pid_t pid); -- 1.7.3.2